WorldWideScience

Sample records for based prosthetic devices

  1. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  2. Surface modification of polyester to produce a bacterial cellulose-based vascular prosthetic device

    Science.gov (United States)

    Charpentier, Paul A.; Maguire, Anne; Wan, Wan-kei

    2006-07-01

    The surface of medical grade polyesters was modified to impart hydrophilic character for attachment to bacterial synthesized cellulose to produce a vascular prosthetic device. The polyesters were treated with UV/ozone, air plasma, and nitrogen plasma for various lengths of time. The unmodified and modified surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and advancing contact angle measurements. The surfaces were then coated with bacterial produced cellulose to study adhesion properties through tensile testing (peel testing). UV/ozone and plasma treatment XPS results indicated an increase in the oxygen concentration in the form of C sbnd O(H) on the treated polyester surfaces. The treatment time to reach steady state in the case of air and nitrogen plasmas took the order of seconds, while 7 min and longer were required for UV/ozone treatment. Peel strength tests to measure adhesion of modified polyester to cellulose reached their maximum values when the C sbnd O(H) concentrations were at the highest level. It was also at this level that the contact angle measurements showed no further decrease.

  3. An extremely lightweight fingernail worn prosthetic interface device

    Science.gov (United States)

    Yetkin, Oguz; Ahluwalia, Simranjit; Silva, Dinithi; Kasi-Okonye, Isioma; Volker, Rachael; Baptist, Joshua R.; Popa, Dan O.

    2016-05-01

    Upper limb prosthetics are currently operated using several electromyography sensors mounted on an amputee's residual limb. In order for any prosthetic driving interface to be widely adopted, it needs to be responsive, lightweight, and out of the way when not being used. In this paper we discuss the possibility of replacing such electrodes with fingernail optical sensor systems mounted on the sound limb. We present a prototype device that can detect pinch gestures and communicate with the prosthetic system. The device detects the relative position of fingers to each other by measuring light transmitted via tissue. Applications are not limited to prosthetic control, but can be extended to other human-machine interfaces.

  4. 42 CFR 414.228 - Prosthetic and orthotic devices.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Prosthetic and orthotic devices. 414.228 Section 414.228 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment...

  5. Control of a powered prosthetic device via a pinch gesture interface

    Science.gov (United States)

    Yetkin, Oguz; Wallace, Kristi; Sanford, Joseph D.; Popa, Dan O.

    2015-06-01

    A novel system is presented to control a powered prosthetic device using a gesture tracking system worn on a user's sound hand in order to detect different grasp patterns. Experiments are presented with two different gesture tracking systems: one comprised of Conductive Thimbles worn on each finger (Conductive Thimble system), and another comprised of a glove which leaves the fingers free (Conductive Glove system). Timing tests were performed on the selection and execution of two grasp patterns using the Conductive Thimble system and the iPhone app provided by the manufacturer. A modified Box and Blocks test was performed using Conductive Glove system and the iPhone app provided by Touch Bionics. The best prosthetic device performance is reported with the developed Conductive Glove system in this test. Results show that these low encumbrance gesture-based wearable systems for selecting grasp patterns may provide a viable alternative to EMG and other prosthetic control modalities, especially for new prosthetic users who are not trained in using EMG signals.

  6. Efficiency of voluntary opening hand and hook prosthetic devices: 24 years of development?

    OpenAIRE

    Gerwin Smit, MSc; Raoul M. Bongers, MSc, PhD; Corry K. van der Sluis, MD, PhD; Dick H. Plettenburg, MSc, PhD

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the best tested device. A second goal was to see whether VO devices have improved in the last two decades. Nine devices (four hooks and five hands) were quantitatively tested (Hosmer model 5XA hook, Hos...

  7. Efficiency of voluntary opening hand and hook prosthetic devices, 24 years of development?

    NARCIS (Netherlands)

    Smit, G.; Bongers, R.M.; Van der Sluis, C.K.; Plettenburg, D.H.

    2012-01-01

    Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO) prosthetic terminal devices and select the b

  8. Shape-memory alloy overload protection device for osseointegrated transfemoral implant prosthetic limb attachment system

    Science.gov (United States)

    Xu, Wei; Shao, Fei; Hughes, Steven

    2002-11-01

    The osseointegrated trans-femoral implant system provides a direct anchoring technique to attach prosthetic limb. This technique was first introduced PI Brenmark in Sweden. The UK had the first clinical trial in 1997 and currently has 6 active limb wearers. The success of this procedure has the potential for improved gait function and mobility, increased employability and significant long-term improvements in the quality of life for above knee amputees. However, the significant load involved in the trans-femoral implant system has caused permanent deformation and/or fractures of the implant abutment in several occasions. To protect the implant system, the implant abutment in particularly, an overloading protection device was introduced. The device uses mechanical mechanism to release torsion overload on the abutment. However, the bending overload protection remains unsolved. To solve the problem, a new overload protection device was developed. This device uses SMA component for bending overload protection. In this paper, the results of non-linear finite element modelling of the SMA and steel (AISI 1040) components were presented. Experiments were also carried out using steel components to assess the design which is based on the non-linear property of the materials.

  9. Simulating The Technological Movements Of The Equipment Used For Manufacturing Prosthetic Devices Using 3D Models

    Science.gov (United States)

    Chicea, Anca-Lucia

    2015-09-01

    The paper presents the process of building geometric and kinematic models of a technological equipment used in the process of manufacturing devices. First, the process of building the model for a six axes industrial robot is presented. In the second part of the paper, the process of building the model for a five-axis CNC milling machining center is also shown. Both models can be used for accurate cutting processes simulation of complex parts, such as prosthetic devices.

  10. Surface EMG and intra-socket force measurement to control a prosthetic device

    Science.gov (United States)

    Sanford, Joe; Patterson, Rita; Popa, Dan

    2015-06-01

    Surface electromyography (SEMG) has been shown to be a robust and reliable interaction method allowing for basic control of powered prosthetic devices. Research has shown a marked decrease in EMG-classification efficiency throughout activities of daily life due to socket shift and movement and fatigue as well as changes in degree of fit of the socket throughout the subject's lifetime. Users with the most severe levels of amputation require the most complex devices with the greatest number of degrees of freedom. Controlling complex dexterous devices with limited available inputs requires the addition of sensing and interaction modalities. However, the larger the amputation severity, the fewer viable SEMG sites are available as control inputs. Previous work reported the use of intra-socket pressure, as measured during wrist flexion and extension, and has shown that it is possible to control a powered prosthetic device with pressure sensors. In this paper, we present data correlations of SEMG data with intra-socket pressure data. Surface EMG sensors and force sensors were housed within a simulated prosthetic cuff fit to a healthy-limbed subject. EMG and intra-socket force data was collected from inside the cuff as a subject performed pre-defined grip motions with their dominant hand. Data fusion algorithms were explored and allowed a subject to use both intra-socket pressure and SEMG data as control inputs for a powered prosthetic device. This additional input modality allows for an improvement in input classification as well as information regarding socket fit through out activities of daily life.

  11. Hybrid nanostructured coating for increased resistance of prosthetic devices to staphylococcal colonization

    Science.gov (United States)

    Anghel, Ion; Grumezescu, Alexandru Mihai

    2013-01-01

    Prosthetic medical device-associated infections are responsible for significant morbidity and mortality rates. Novel improved materials and surfaces exhibiting inappropriate conditions for microbial development are urgently required in the medical environment. This study reveals the benefit of using natural Mentha piperita essential oil, combined with a 5 nm core/shell nanosystem-improved surface exhibiting anti-adherence and antibiofilm properties. This strategy reveals a dual role of the nano-oil system; on one hand, inhibiting bacterial adherence and, on the other hand, exhibiting bactericidal effect, the core/shell nanosystem is acting as a controlled releasing machine for the essential oil. Our results demonstrate that this dual nanobiosystem is very efficient also for inhibiting biofilm formation, being a good candidate for the design of novel material surfaces used for prosthetic devices.

  12. [Effect of prosthesis cleansing agent on the prosthetic base fungi].

    Science.gov (United States)

    Temmer, K; Stipetić, D; Cekić-Arambasin, A; Kraljević, K

    1991-01-01

    Candida albicans and other fungi are frequently found in subjects wearing prostheses, especially in prostheses with poor hygiene, i.e. with accumulations of food, plaques and calculi. The aim of this study was to assess the efficacy of Corega extradent relative to fungi adhering to the prosthetic base. Results of the study showed the prosthesis hygiene to be substantially related to inflammation of palatal mucosa. The mean number of fungi per sq.cm of prosthetic base was 64 x 10(5). The number of fungi was redetermined after a two-day treatment with Corega extradent, with unchanged other habits of the prosthesis wearing and cleansing. The number of fungi decreased in all study subjects, the mean value of individual differences being 2238 times. In prostheses with a great number of fungi and extremely poor hygiene, the effect of Corega extradent was poorer, indicating the need of additional mechanical cleansing with a brush. PMID:1819938

  13. Long-term outcome after implantation of prosthetic disc nucleus device (PDN) in lumbar disc disease

    OpenAIRE

    Selviaridis, P; Foroglou, N; Tsitlakidis, A; Hatzisotiriou, A; Magras, I; Patsalas, I

    2010-01-01

    Background: The prosthetic disc nucleus (PDN) device offers an adjunct treatment for patients with degenerative disc disease and herniation, who necessitate surgical intervention, avoiding total-disc replacement or fusion. This prospective, clinical study aimed to gauge the long-term effectiveness of microdiscectomy followed by PDN implantation in relieving pain and improving functional status in patients with symptomatic degenerative lumbar disc disease and herniation.

  14. Optimising the prescription of prosthetic technologies (opptec): Outcome measures for evidence based prosthetic practice and use

    LENUS (Irish Health Repository)

    Ryall, Dr Nicola

    2010-01-01

    This study provided a forum for patients and service providers to voice their opinions in what they believe to be the important predictors and outcomes involved in successful rehabilitation following limb loss. To develop a consensus on the most important outcomes and factors to address for both the lower limb and upper limb prosthetic prescription process, the above data relating to lower limb and upper prosthetics were subsequently used in the next phase of the research involving two Delphi surveys of 23 and 53 experts within the lower limb and upper limb amputation and prosthetic field respectively, including users, service providers and researchers.\\r\

  15. Neuronal ensemble control of prosthetic devices by a human with tetraplegia

    Science.gov (United States)

    Hochberg, Leigh R.; Serruya, Mijail D.; Friehs, Gerhard M.; Mukand, Jon A.; Saleh, Maryam; Caplan, Abraham H.; Branner, Almut; Chen, David; Penn, Richard D.; Donoghue, John P.

    2006-07-01

    Neuromotor prostheses (NMPs) aim to replace or restore lost motor functions in paralysed humans by routeing movement-related signals from the brain, around damaged parts of the nervous system, to external effectors. To translate preclinical results from intact animals to a clinically useful NMP, movement signals must persist in cortex after spinal cord injury and be engaged by movement intent when sensory inputs and limb movement are long absent. Furthermore, NMPs would require that intention-driven neuronal activity be converted into a control signal that enables useful tasks. Here we show initial results for a tetraplegic human (MN) using a pilot NMP. Neuronal ensemble activity recorded through a 96-microelectrode array implanted in primary motor cortex demonstrated that intended hand motion modulates cortical spiking patterns three years after spinal cord injury. Decoders were created, providing a `neural cursor' with which MN opened simulated e-mail and operated devices such as a television, even while conversing. Furthermore, MN used neural control to open and close a prosthetic hand, and perform rudimentary actions with a multi-jointed robotic arm. These early results suggest that NMPs based upon intracortical neuronal ensemble spiking activity could provide a valuable new neurotechnology to restore independence for humans with paralysis.

  16. Percutaneous closure of an aortic prosthetic paravalvular leak with device in a patient presenting with heart failure

    Directory of Open Access Journals (Sweden)

    Altug Osken

    2015-01-01

    Full Text Available Paravalvular leaks (PVLs are a well-recognized complication of prosthetic valve replacement. Perivalvular prosthetic regurgitation causes significant morbidity and is associated with high perioperative mortality if open surgical repair is required. PVLs manifest with symptoms of congestive heart failure, hemolysis, or in most cases, the combination of both. In recent years, the development of imaging and device techniques significantly shortened the duration of fluoroscopy and procedure success was achieved. Percutaneous transcatheter closure of PVLs with a specific device causes symptomatic improvement. We present a case of transcatheter closure of aortic paravalvular insufficiency with amplatzer duct occluder 2 device.

  17. Efficiency of voluntary opening hand and hook prosthetic devices: 24 years of development?

    Directory of Open Access Journals (Sweden)

    Gerwin Smit, MSc

    2012-06-01

    Full Text Available Quantitative data on the mechanical performance of upper-limb prostheses are very important in prostheses development and selection. The primary goal of this study was to objectively evaluate the mechanical performance of adult-size voluntary opening (VO prosthetic terminal devices and select the best tested device. A second goal was to see whether VO devices have improved in the last two decades. Nine devices (four hooks and five hands were quantitatively tested (Hosmer model 5XA hook, Hosmer Sierra 2 Load VO hook, RSL Steeper Carbon Gripper, Otto Bock model 10A60 hook, Becker Imperial hand, Hosmer Sierra VO hand, Hosmer Soft VO hand, RSL Steeper VO hand, Otto Bock VO hand. We measured the pinch forces, activation forces, cable displacements, mass, and opening span and calculated the work and hysteresis. We compared the results with data from 1987. Hooks required lower activation forces and delivered higher pinch forces than hands. The activation forces of several devices were very high. The pinch forces of all tested hands were too low. The Hosmer model 5XA hook with three bands was the best tested hook. The Hosmer Sierra VO hand was the best tested hand. We found no improvements in VO devices compared with the data from 1987.

  18. Simulated Prosthetic Vision: The Benefits of Computer-Based Object Recognition and Localization.

    Science.gov (United States)

    Macé, Marc J-M; Guivarch, Valérian; Denis, Grégoire; Jouffrais, Christophe

    2015-07-01

    Clinical trials with blind patients implanted with a visual neuroprosthesis showed that even the simplest tasks were difficult to perform with the limited vision restored with current implants. Simulated prosthetic vision (SPV) is a powerful tool to investigate the putative functions of the upcoming generations of visual neuroprostheses. Recent studies based on SPV showed that several generations of implants will be required before usable vision is restored. However, none of these studies relied on advanced image processing. High-level image processing could significantly reduce the amount of information required to perform visual tasks and help restore visuomotor behaviors, even with current low-resolution implants. In this study, we simulated a prosthetic vision device based on object localization in the scene. We evaluated the usability of this device for object recognition, localization, and reaching. We showed that a very low number of electrodes (e.g., nine) are sufficient to restore visually guided reaching movements with fair timing (10 s) and high accuracy. In addition, performance, both in terms of accuracy and speed, was comparable with 9 and 100 electrodes. Extraction of high level information (object recognition and localization) from video images could drastically enhance the usability of current visual neuroprosthesis. We suggest that this method-that is, localization of targets of interest in the scene-may restore various visuomotor behaviors. This method could prove functional on current low-resolution implants. The main limitation resides in the reliability of the vision algorithms, which are improving rapidly. PMID:25900238

  19. Pilot Study for OCT Guided Design and Fit of a Prosthetic Device for Treatment of Corneal Disease

    Directory of Open Access Journals (Sweden)

    Hong-Gam T. Le

    2012-01-01

    Full Text Available Purpose. To assess optical coherence tomography (OCT for guiding design and fit of a prosthetic device for corneal disease. Methods. A prototype time domain OCT scanner was used to image the anterior segment of patients fitted with large diameter (18.5–20 mm prosthetic devices for corneal disease. OCT images were processed and analyzed to characterize corneal diameter, corneal sagittal height, scleral sagittal height, scleral toricity, and alignment of device. Within-subject variance of OCT-measured parameters was evaluated. OCT-measured parameters were compared with device parameters for each eye fitted. OCT image correspondence with ocular alignment and clinical fit was assessed. Results. Six eyes in 5 patients were studied. OCT measurement of corneal diameter (coefficient of variation, %, cornea sagittal height (%, and scleral sagittal height (% is highly repeatable within each subject. OCT image-derived measurements reveal strong correlation between corneal sagittal height and device corneal height ( and modest correlation between scleral and on-eye device toricity (. Qualitative assessment of a fitted device on OCT montages reveals correspondence with slit lamp images and clinical assessment of fit. Conclusions. OCT imaging of the anterior segment is suitable for custom design and fit of large diameter (18.5–20 mm prosthetic devices used in the treatment of corneal disease.

  20. Design and evaluation of voluntary opening and voluntary closing prosthetic terminal device

    Directory of Open Access Journals (Sweden)

    Jon W. Sensinger, PhD, PEng

    2015-04-01

    Full Text Available Body-powered prostheses use a cable-operated system to generate forces and move prosthetic joints. However, this control system can only generate forces in one direction, so current body-powered prehensor designs allow the user either to voluntarily open or voluntarily close the tongs. Both voluntary opening (VO and voluntary closing (VC modes of operation have advantages for certain tasks, and many end-users desire a terminal device (TD that can switch between the two modes. However, such a TD must maintain the same thumb position (i.e., point of Bowden cable attachment and movement direction in both modes in order to avoid the need to readjust the harness after every mode switch. In this study, we demonstrate a simple design that fulfills these requirements while allowing the user to switch easily between modes. We describe the design concept, describe a rugged split-hook prototype, provide specifications (size, weight, efficiency, etc., and present a pilot study in which five subjects with intact arms and two subjects with amputation used the VO and VC split-hook prehensor to perform the Southampton Hand Assessment Procedure. Subjects performed an average of 4 to 7 (+/??? 0.2 points better when they could choose to switch between modes on a task-by-task basis than when they were constrained to using only VO or VC modes.

  1. Prosthetic Engineering

    Science.gov (United States)

    ... Overview CoE for Limb Loss Prevention and Prosthetic Engineering Menu Menu VA Center of Excellence for Limb ... ZIP code here Enter ZIP code here Prosthetic Engineering - Overview Our aim is to improve prosthetic prescription ...

  2. A sensory feedback system for prosthetic hand based on evoked tactile sensation.

    Science.gov (United States)

    Liu, X X; Chai, G H; Qu, H E; Lan, N

    2015-08-01

    The lack of reliable sensory feedback has been one of the barriers in prosthetic hand development. Restoring sensory function from prosthetic hand to amputee remains a great challenge to neural engineering. In this paper, we present the development of a sensory feedback system based on the phenomenon of evoked tactile sensation (ETS) at the stump skin of residual limb induced by transcutaneous electrical nerve stimulation (TENS). The system could map a dynamic pattern of stimuli to an electrode placed on the corresponding projected finger areas on the stump skin. A pressure transducer placed at the tip of prosthetic fingers was used to sense contact pressure, and a high performance DSP processor sampled pressure signals, and calculated the amplitude of feedback stimulation in real-time. Biphasic and charge-balanced current pulses with amplitude modulation generated by a multi-channel laboratory stimulator were delivered to activate sensory nerves beneath the skin. We tested this sensory feedback system in amputee subjects. Preliminary results showed that the subjects could perceive different levels of pressure at the tip of prosthetic finger through evoked tactile sensation (ETS) with distinct grades and modalities. We demonstrated the feasibility to restore the perceptual sensation from prosthetic fingers to amputee based on the phenomenon of evoked tactile sensation (ETS) with TENS. PMID:26736798

  3. OCT-based profiler for automating ocular surface prosthetic fitting (Conference Presentation)

    Science.gov (United States)

    Mujat, Mircea; Patel, Ankit H.; Maguluri, Gopi N.; Iftimia, Nicusor V.; Patel, Chirag; Agranat, Josh; Tomashevskaya, Olga; Bonte, Eugene; Ferguson, R. Daniel

    2016-03-01

    The use of a Prosthetic Replacement of the Ocular Surface Environment (PROSE) device is a revolutionary treatment for military patients that have lost their eyelids due to 3rd degree facial burns and for civilians who suffer from a host of corneal diseases. However, custom manual fitting is often a protracted painful, inexact process that requires multiple fitting sessions. Training for new practitioners is a long process. Automated methods to measure the complete corneal and scleral topology would provide a valuable tool for both clinicians and PROSE device manufacturers and would help streamline the fitting process. PSI has developed an ocular anterior-segment profiler based on Optical Coherence Tomography (OCT), which provides a 3D measure of the surface of the sclera and cornea. This device will provide topography data that will be used to expedite and improve the fabrication process for PROSE devices. OCT has been used to image portions of the cornea and sclera and to measure surface topology for smaller contact lenses [1-3]. However, current state-of-the-art anterior eye OCT systems can only scan about 16 mm of the eye's anterior surface, which is not sufficient for covering the sclera around the cornea. In addition, there is no systematic method for scanning and aligning/stitching the full scleral/corneal surface and commercial segmentation software is not optimized for the PROSE application. Although preliminary, our results demonstrate the capability of PSI's approach to generate accurate surface plots over relatively large areas of the eye, which is not currently possible with any other existing platform. Testing the technology on human volunteers is currently underway at Boston Foundation for Sight.

  4. Development and testing of new upper-limb prosthetic devices: Research designs for usability testing

    OpenAIRE

    Linda Resnik, PT, PhD

    2011-01-01

    The purposes of this article are to describe usability testing and introduce designs and methods of usability testing research as it relates to upper-limb prosthetics. This article defines usability, describes usability research, discusses research approaches to and designs for usability testing, and highlights a variety of methodological considerations, including sampling, sample size requirements, and usability metrics. Usability testing is compared with other types of study designs used in...

  5. Cellular Modulation of Polymeric Device Surfaces: Promise of Adult Stem Cells for Neuro-Prosthetics

    OpenAIRE

    Richter, Anja; Kruse, Charli; Moser, Andreas; Hofmann, Ulrich G.; Danner, Sandra

    2011-01-01

    Minimizing the foreign body response is seen as one critical research strategy for implants especially when designed for immune-privileged organs like the brain. The context of this work is to improve deep brain stimulating devices used in a consistently growing spectrum of psychomotor and psychiatric diseases mainly in form of stiff electrodes. Based on the compliance match hypothesis of biocompatibility we present another step forward using flexible implant materials covered with brain cell...

  6. Prosthetic avian vocal organ controlled by a freely behaving bird based on a low dimensional model of the biomechanical periphery.

    Directory of Open Access Journals (Sweden)

    Ezequiel M Arneodo

    Full Text Available Because of the parallels found with human language production and acquisition, birdsong is an ideal animal model to study general mechanisms underlying complex, learned motor behavior. The rich and diverse vocalizations of songbirds emerge as a result of the interaction between a pattern generator in the brain and a highly nontrivial nonlinear periphery. Much of the complexity of this vocal behavior has been understood by studying the physics of the avian vocal organ, particularly the syrinx. A mathematical model describing the complex periphery as a nonlinear dynamical system leads to the conclusion that nontrivial behavior emerges even when the organ is commanded by simple motor instructions: smooth paths in a low dimensional parameter space. An analysis of the model provides insight into which parameters are responsible for generating a rich variety of diverse vocalizations, and what the physiological meaning of these parameters is. By recording the physiological motor instructions elicited by a spontaneously singing muted bird and computing the model on a Digital Signal Processor in real-time, we produce realistic synthetic vocalizations that replace the bird's own auditory feedback. In this way, we build a bio-prosthetic avian vocal organ driven by a freely behaving bird via its physiologically coded motor commands. Since it is based on a low-dimensional nonlinear mathematical model of the peripheral effector, the emulation of the motor behavior requires light computation, in such a way that our bio-prosthetic device can be implemented on a portable platform.

  7. Post-operative orbital imaging: a focus on implants and prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Ashok [Royal London Hospital, Diagnostic Neuroradiology, Barts Health NHS Trust, London (United Kingdom); Mankad, Kshitij [Great Ormond Street Hospital, Diagnostic Neuroradiology, London (United Kingdom); Poitelea, Cornelia; Verity, David H. [Moorfields Eye Hospital, London (United Kingdom); Davagnanam, Indran [National Hospital for Neurology and Neurosurgery, London (United Kingdom)

    2014-11-15

    Accurate interpretation of orbital imaging in the presence of either orbital implants requires a sound knowledge of both the surgical approach used and the imaging characteristics of the implanted devices themselves. In this article, the radiological appearance of the various devices used in ophthalmology, and their relationship to other orbital structures, is reviewed. In addition, the intended anatomical location, function of these devices, and clinical indications for their use are provided. (orig.)

  8. Lightweight custom composite prosthetic components using an additive manufacturing-based molding technique.

    Science.gov (United States)

    Leddy, Michael T; Belter, Joseph T; Gemmell, Kevin D; Dollar, Aaron M

    2015-08-01

    Additive manufacturing techniques are becoming more prominent and cost-effective as 3D printing becomes higher quality and more inexpensive. The idea of 3D printed prosthetics components promises affordable, customizable devices, but these systems currently have major shortcomings in durability and function. In this paper, we propose a fabrication method for custom composite prostheses utilizing additive manufacturing, allowing for customizability, as well the durability of professional prosthetics. The manufacturing process is completed using 3D printed molds in a multi-stage molding system, which creates a custom finger or palm with a lightweight epoxy foam core, a durable composite outer shell, and soft urethane gripping surfaces. The composite material was compared to 3D printed and aluminum materials using a three-point bending test to compare stiffness, as well as gravimetric measurements to compare weight. The composite finger demonstrates the largest stiffness with the lowest weight compared to other tested fingers, as well as having customizability and lower cost, proving to potentially be a substantial benefit to the development of upper-limb prostheses. PMID:26737367

  9. Safety and effectiveness considerations for clinical studies of visual prosthetic devices

    Science.gov (United States)

    Cohen, Ethan D.

    2007-03-01

    With the advent of new designs of visual prostheses for the blind, FDA is faced with developing guidance for evaluating their engineering, safety and patient performance. Visual prostheses are considered significant risk medical devices, and their use in human clinical trials must be approved by FDA under an investigation device exemption (IDE). This paper contains a series of test topics and design issues that sponsors should consider in order to assess the safety and efficacy of their device. The IDE application includes a series of pre-clinical and clinical data sections. The pre-clinical section documents laboratory, animal and bench top performance tests of visual prostheses safety and reliability to support a human clinical trial. The materials used in constructing the implant should be biocompatible, sterile, corrosion resistant, and able to withstand any forces exerted on it during normal patient use. The clinical data section is composed of items related to patient-related evaluation of device performance. This section documents the implantation procedure, trial design, statistical analysis and how visual performance is assessed. Similar to cochlear implants, a visual prosthesis is expected to last in the body for many years, and good pre-clinical and clinical testing will help ensure its safety, durability and effectiveness.

  10. Psychophysical testing of visual prosthetic devices: a call to establish a multi-national joint task force

    Science.gov (United States)

    Rizzo, Joseph F., III; Ayton, Lauren N.

    2014-04-01

    Recent advances in the field of visual prostheses, as showcased in this special feature of Journal of Neural Engineering , have led to promising results from clinical trials of a number of devices. However, as noted by these groups there are many challenges involved in assessing vision of people with profound vision loss. As such, it is important that there is consistency in the methodology and reporting standards for clinical trials of visual prostheses and, indeed, the broader vision restoration research field. Two visual prosthesis research groups, the Boston Retinal Implant Project (BRIP) and Bionic Vision Australia (BVA), have agreed to work cooperatively to establish a multi-national Joint Task Force. The aim of this Task Force will be to develop a consensus statement to guide the methods used to conduct and report psychophysical and clinical results of humans who receive visual prosthetic devices. The overarching goal is to ensure maximum benefit to the implant recipients, not only in the outcomes of the visual prosthesis itself, but also in enabling them to obtain accurate information about this research with ease. The aspiration to develop a Joint Task Force was first promulgated at the inaugural 'The Eye and the Chip' meeting in September 2000. This meeting was established to promote the development of the visual prosthetic field by applying the principles of inclusiveness, openness, and collegiality among the growing body of researchers in this field. These same principles underlie the intent of this Joint Task Force to enhance the quality of psychophysical research within our community. Despite prior efforts, a critical mass of interested parties could not congeal. Renewed interest for developing joint guidelines has developed recently because of a growing awareness of the challenges of obtaining reliable measurements of visual function in patients who are severely visually impaired (in whom testing is inherently noisy), and of the importance of

  11. Psycho-physiological assessment of a prosthetic hand sensory feedback system based on an auditory display: a preliminary study

    Directory of Open Access Journals (Sweden)

    Gonzalez Jose

    2012-06-01

    Full Text Available Abstract Background Prosthetic hand users have to rely extensively on visual feedback, which seems to lead to a high conscious burden for the users, in order to manipulate their prosthetic devices. Indirect methods (electro-cutaneous, vibrotactile, auditory cues have been used to convey information from the artificial limb to the amputee, but the usability and advantages of these feedback methods were explored mainly by looking at the performance results, not taking into account measurements of the user’s mental effort, attention, and emotions. The main objective of this study was to explore the feasibility of using psycho-physiological measurements to assess cognitive effort when manipulating a robot hand with and without the usage of a sensory substitution system based on auditory feedback, and how these psycho-physiological recordings relate to temporal and grasping performance in a static setting. Methods 10 male subjects (26+/-years old, participated in this study and were asked to come for 2 consecutive days. On the first day the experiment objective, tasks, and experiment setting was explained. Then, they completed a 30 minutes guided training. On the second day each subject was tested in 3 different modalities: Auditory Feedback only control (AF, Visual Feedback only control (VF, and Audiovisual Feedback control (AVF. For each modality they were asked to perform 10 trials. At the end of each test, the subject had to answer the NASA TLX questionnaire. Also, during the test the subject’s EEG, ECG, electro-dermal activity (EDA, and respiration rate were measured. Results The results show that a higher mental effort is needed when the subjects rely only on their vision, and that this effort seems to be reduced when auditory feedback is added to the human-machine interaction (multimodal feedback. Furthermore, better temporal performance and better grasping performance was obtained in the audiovisual modality. Conclusions The performance

  12. Transluminal placement of a prosthetic graft-stent device for treatment of subclavian artery aneurysm.

    Science.gov (United States)

    May, J; White, G; Waugh, R; Yu, W; Harris, J

    1993-12-01

    A 78-year-old man was seen with an expanding 5 cm false aneurysm of the right subclavian artery. This was treated by an intraluminal graft-stent device introduced through the brachial artery via a 16 F sheath. The graft was constructed from two polytetrafluoroethylene patches of 0.4 mm thickness and anchored in the subclavian artery by an 8 mm stainless steel stent. The procedure was monitored by an image intensifier. Completion arteriography and postoperative duplex scanning confirmed normal flow through the subclavian artery with no communication between the lumen and the aneurysmal sac. The patient recovered without complication. PMID:8264035

  13. 21 CFR 895.101 - Prosthetic hair fibers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prosthetic hair fibers. 895.101 Section 895.101...) MEDICAL DEVICES BANNED DEVICES Listing of Banned Devices § 895.101 Prosthetic hair fibers. Prosthetic hair fibers are devices intended for implantation into the human scalp to simulate natural hair or...

  14. Psychophysical testing of visual prosthetic devices: a call to establish a multi-national joint task force

    Science.gov (United States)

    Rizzo, Joseph F., III; Ayton, Lauren N.

    2014-04-01

    Recent advances in the field of visual prostheses, as showcased in this special feature of Journal of Neural Engineering , have led to promising results from clinical trials of a number of devices. However, as noted by these groups there are many challenges involved in assessing vision of people with profound vision loss. As such, it is important that there is consistency in the methodology and reporting standards for clinical trials of visual prostheses and, indeed, the broader vision restoration research field. Two visual prosthesis research groups, the Boston Retinal Implant Project (BRIP) and Bionic Vision Australia (BVA), have agreed to work cooperatively to establish a multi-national Joint Task Force. The aim of this Task Force will be to develop a consensus statement to guide the methods used to conduct and report psychophysical and clinical results of humans who receive visual prosthetic devices. The overarching goal is to ensure maximum benefit to the implant recipients, not only in the outcomes of the visual prosthesis itself, but also in enabling them to obtain accurate information about this research with ease. The aspiration to develop a Joint Task Force was first promulgated at the inaugural 'The Eye and the Chip' meeting in September 2000. This meeting was established to promote the development of the visual prosthetic field by applying the principles of inclusiveness, openness, and collegiality among the growing body of researchers in this field. These same principles underlie the intent of this Joint Task Force to enhance the quality of psychophysical research within our community. Despite prior efforts, a critical mass of interested parties could not congeal. Renewed interest for developing joint guidelines has developed recently because of a growing awareness of the challenges of obtaining reliable measurements of visual function in patients who are severely visually impaired (in whom testing is inherently noisy), and of the importance of

  15. Rehabilitation and Prosthetic Services

    Science.gov (United States)

    ... Therapy Mental Health Physical Medicine and Rehabilitation Services Physical Therapy Prosthetic and Sensory Aids Service Benefits Prosthetic and Sensory Aids Service General Information Prosthetic ...

  16. Principal components analysis based control of a multi-dof underactuated prosthetic hand

    Directory of Open Access Journals (Sweden)

    Magenes Giovanni

    2010-04-01

    Full Text Available Abstract Background Functionality, controllability and cosmetics are the key issues to be addressed in order to accomplish a successful functional substitution of the human hand by means of a prosthesis. Not only the prosthesis should duplicate the human hand in shape, functionality, sensorization, perception and sense of body-belonging, but it should also be controlled as the natural one, in the most intuitive and undemanding way. At present, prosthetic hands are controlled by means of non-invasive interfaces based on electromyography (EMG. Driving a multi degrees of freedom (DoF hand for achieving hand dexterity implies to selectively modulate many different EMG signals in order to make each joint move independently, and this could require significant cognitive effort to the user. Methods A Principal Components Analysis (PCA based algorithm is used to drive a 16 DoFs underactuated prosthetic hand prototype (called CyberHand with a two dimensional control input, in order to perform the three prehensile forms mostly used in Activities of Daily Living (ADLs. Such Principal Components set has been derived directly from the artificial hand by collecting its sensory data while performing 50 different grasps, and subsequently used for control. Results Trials have shown that two independent input signals can be successfully used to control the posture of a real robotic hand and that correct grasps (in terms of involved fingers, stability and posture may be achieved. Conclusions This work demonstrates the effectiveness of a bio-inspired system successfully conjugating the advantages of an underactuated, anthropomorphic hand with a PCA-based control strategy, and opens up promising possibilities for the development of an intuitively controllable hand prosthesis.

  17. Prosthetics / Amputations

    Science.gov (United States)

    PrOstHetics/liMb lOss VA researchers are exploring the use of leading-edge technology such as robotics, tissue engineering, and nanotechnology ... prosthetic components to the needs of Veterans with limb loss—especially those who seek to maintain an active ...

  18. Prosthetic Feet

    Science.gov (United States)

    ... age, weight, foot size, activity level, and job needs. Here are some facts to know: Basic Prosthetic Feet There are two types of basic ... knee from buckling add weight to the prosthesis, need periodic repair and cost a little more than most basic feet are often used by people who need ...

  19. Efficacy of a novel PCR- and microarray-based method in diagnosis of a prosthetic joint infection

    OpenAIRE

    Metso, Leena; Mäki, Minna; Tissari, Päivi; Remes, Ville; Piiparinen, Pasi; Kirveskari, Juha; Tarkka, Eveliina; Anttila, Veli-Jukka; Vaara, Martti; Huotari, Kaisa

    2014-01-01

    Background and purpose Polymerase chain reaction (PCR) methods enable detection and species identification of many pathogens. We assessed the efficacy of a new PCR and microarray-based platform for detection of bacteria in prosthetic joint infections (PJIs). Methods This prospective study involved 61 suspected PJIs in hip and knee prostheses and 20 negative controls. 142 samples were analyzed by Prove-it Bone and Joint assay. The laboratory staff conducting the Prove-it analysis were not awar...

  20. Design of Shape Memory Alloy-Based and Tendon-Driven Actuated Fingers Towards a Hybrid Anthropomorphic Prosthetic Hand

    OpenAIRE

    Erkan Kaplanoglu

    2012-01-01

    This paper presents the design of tendon‐driven actuated fingers using a shape memory alloy for a hybrid anthropomorphic prosthetic hand. The ring and little (pinky) fingers are selected for shape memory activation due to their lower degree of movement during multiple grasping configurations. The fingersʹ tendon system is based on shape memory alloy (SMA) wires that form artificial muscle pairs for the required flexion/extension of the finger joints. The finger has four degrees of freedom suc...

  1. Asphaltene based photovoltaic devices

    Science.gov (United States)

    Chianelli, Russell R.; Castillo, Karina; Gupta, Vipin; Qudah, Ali M.; Torres, Brenda; Abujnah, Rajib E.

    2016-03-22

    Photovoltaic devices and methods of making the same, are disclosed herein. The cell comprises a photovoltaic device that comprises a first electrically conductive layer comprising a photo-sensitized electrode; at least one photoelectrochemical layer comprising metal-oxide particles, an electrolyte solution comprising at least one asphaltene fraction, wherein the metal-oxide particles are optionally dispersed in a surfactant; and a second electrically conductive layer comprising a counter-electrode, wherein the second electrically conductive layer comprises one or more conductive elements comprising carbon, graphite, soot, carbon allotropes or any combinations thereof.

  2. Myoelectric control of prosthetic hands: state-of-the-art review

    Directory of Open Access Journals (Sweden)

    Geethanjali P

    2016-07-01

    Full Text Available Purushothaman Geethanjali School of Electrical Engineering Department of Control and Automation VIT University, Vellore, Tamil Nadu, India Abstract: Myoelectric signals (MES have been used in various applications, in particular, for identification of user intention to potentially control assistive devices for amputees, orthotic devices, and exoskeleton in order to augment capability of the user. MES are also used to estimate force and, hence, torque to actuate the assistive device. The application of MES is not limited to assistive devices, and they also find potential applications in teleoperation of robots, haptic devices, virtual reality, and so on. The myoelectric control-based prosthetic hand aids to restore activities of daily living of amputees in order to improve the self-esteem of the user. All myoelectric control-based prosthetic hands may not have similar operations and exhibit variation in sensing input, deciphering the signals, and actuating prosthetic hand. Researchers are focusing on improving the functionality of prosthetic hand in order to suit the user requirement with the different operating features. The myoelectric control differs in operation to accommodate various external factors. This article reviews the state of the art of myoelectric prosthetic hand, giving description of each control strategy. Keywords: EMG, assistive device, amputee, myoelectric control, electric powered, body ­powered, bioelectric signal control

  3. Prosthetic synovitis.

    Science.gov (United States)

    Eftekhar, N S; Doty, S B; Johnston, A D; Parisien, M V

    1985-01-01

    The term "prosthetic synovitis" is applied to reactive changes resulting from a synovial-like membrane formed between a failed prosthesis (noninfected) and the bone interface. This report is the result of light-microscopic and clinical examination of more than 100 specimens obtained at surgery of failed previous hip replacements. The morphology and cell distribution of those tissues removed at surgery in 51 noninfected cemented total hip operations allowed a quantitative estimate of surface cell population by a "touch imprint" technique; qualitative and quantitative estimate (scale, 1 to 4+) of cell population and foreign body materials by light microscopy; and electron microscopy and biochemical analysis of selected samples. Histologic examination included the following cell population, in decreasing order of frequency: acidophilic histiocytes (95%); giant cells (80%); fibronoid material (80%); lymphocyte and plasma cells (26%); and neutrophils (8%). Microscopic examination showed that the largest particles of acrylic cement and shards of high-density polyethylene appeared to be walled off by connective tissue capsules. The majority of smaller particles were incorporated into the histiocyte/macrophage or giant cell population. Histochemistry indicated that these particles elicited "foci" of cellular activity within the synovial-like membrane. This increased activity included the appearance of increased endogenous peroxidase activity in those macrophages within the "foci"; increased betagalactosidae activity among these histiocytes; and a localization of acid phosphates activity within giant cells along the borders of inclusions within the cell cytoplasm. We conclude that wear products resulting from total hip arthroplasty, including the bone cement, can induce increased lysosomal and proteolytic activity within the histiocyte and giant cell populations. It may be important to emphasize that there were "reactive foci" within the membrane and that the entire

  4. Myoelectric control of prosthetic hands: state-of-the-art review.

    Science.gov (United States)

    Geethanjali, Purushothaman

    2016-01-01

    Myoelectric signals (MES) have been used in various applications, in particular, for identification of user intention to potentially control assistive devices for amputees, orthotic devices, and exoskeleton in order to augment capability of the user. MES are also used to estimate force and, hence, torque to actuate the assistive device. The application of MES is not limited to assistive devices, and they also find potential applications in teleoperation of robots, haptic devices, virtual reality, and so on. The myoelectric control-based prosthetic hand aids to restore activities of daily living of amputees in order to improve the self-esteem of the user. All myoelectric control-based prosthetic hands may not have similar operations and exhibit variation in sensing input, deciphering the signals, and actuating prosthetic hand. Researchers are focusing on improving the functionality of prosthetic hand in order to suit the user requirement with the different operating features. The myoelectric control differs in operation to accommodate various external factors. This article reviews the state of the art of myoelectric prosthetic hand, giving description of each control strategy. PMID:27555799

  5. Application of self-report and performance-based outcome measures to determine functional differences between four categories of prosthetic feet

    Directory of Open Access Journals (Sweden)

    Robert S. Gailey, PhD, PT

    2012-06-01

    Full Text Available We examined the application of outcome measures to determine changes in function caused by standardized functional prosthetic gait training and the use of four different prosthetic feet in people with unilateral transtibial limb loss. Two self-report measures (Prosthetic Evaluation Questionnaire-Mobility Scale [PEQ-13] and Locomotor Capabilities Index [LCI], and three performance-based measures (Amputee Mobility Predictor with a prosthesis [AMPPRO], 6-minute walk test [6MWT] and step activity monitor [SAM] were used. Ten people with unilateral transtibial limb loss, five with peripheral vascular disease (PVD and five without PVD, completed testing. Subjects were tested at baseline and after receiving training with their existing prosthesis and with the study socket and four prosthetic feet, i.e., SACH (solid ankle cushion heel, SAFE (stationary attachment flexible endoskeletal, Talux, and Proprio feet, over 8 to 10 weeks. Training was administered between testing sessions. No differences were detected by the PEQ-13, LCI, 6MWT, or SAM following training and after fitting with test feet. The AMPPRO demonstrated differences following training with the existing prosthesis in the PVD group and between selected feet from baseline testing (p prosthetic feet.

  6. Pursuing prosthetic electronic skin.

    Science.gov (United States)

    Chortos, Alex; Liu, Jia; Bao, Zhenan

    2016-09-01

    Skin plays an important role in mediating our interactions with the world. Recreating the properties of skin using electronic devices could have profound implications for prosthetics and medicine. The pursuit of artificial skin has inspired innovations in materials to imitate skin's unique characteristics, including mechanical durability and stretchability, biodegradability, and the ability to measure a diversity of complex sensations over large areas. New materials and fabrication strategies are being developed to make mechanically compliant and multifunctional skin-like electronics, and improve brain/machine interfaces that enable transmission of the skin's signals into the body. This Review will cover materials and devices designed for mimicking the skin's ability to sense and generate biomimetic signals. PMID:27376685

  7. Limb Prosthetics

    Science.gov (United States)

    ... in the Residual Limb A prosthesis is an artificial device that replaces a missing body part. A limb may be amputated or missing because of a blood vessel disorder (such as atherosclerosis or damage due to ...

  8. Streamline-based microfluidic device

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Zheng, Siyang (Inventor); Kasdan, Harvey (Inventor)

    2013-01-01

    The present invention provides a streamline-based device and a method for using the device for continuous separation of particles including cells in biological fluids. The device includes a main microchannel and an array of side microchannels disposed on a substrate. The main microchannel has a plurality of stagnation points with a predetermined geometric design, for example, each of the stagnation points has a predetermined distance from the upstream edge of each of the side microchannels. The particles are separated and collected in the side microchannels.

  9. Prevention of Prosthetic Dentistry

    Directory of Open Access Journals (Sweden)

    Eremin O.V.

    2011-03-01

    Full Text Available Prevention in prosthetic dentistry is not just a regular oral hygiene and the prevention of caries in the early stages of its development. The initial goal of orthopedic and dental should be the ability to convey to the patient's sense of pros-thetics that proteziruya one saved more. An example is included prosthetic dental arch defects with bridges or single artificial crowns on implants that will prevent movement of teeth and the continuity of the dentition

  10. Cotton-based diagnostic devices.

    Science.gov (United States)

    Lin, Shang-Chi; Hsu, Min-Yen; Kuan, Chen-Meng; Wang, Hsi-Kai; Chang, Chia-Ling; Tseng, Fan-Gang; Cheng, Chao-Min

    2014-01-01

    A good diagnostic procedure avoids wasting medical resources, is easy to use, resists contamination, and provides accurate information quickly to allow for rapid follow-up therapies. We developed a novel diagnostic procedure using a "cotton-based diagnostic device" capable of real-time detection, i.e., in vitro diagnostics (IVD), which avoids reagent contamination problems common to existing biomedical devices and achieves the abovementioned goals of economy, efficiency, ease of use, and speed. Our research reinforces the advantages of an easy-to-use, highly accurate diagnostic device created from an inexpensive and readily available U.S. FDA-approved material (i.e., cotton as flow channel and chromatography paper as reaction zone) that adopts a standard calibration curve method in a buffer system (i.e., nitrite, BSA, urobilinogen and uric acid assays) to accurately obtain semi-quantitative information and limit the cross-contamination common to multiple-use tools. Our system, which specifically targets urinalysis diagnostics and employs a multiple biomarker approach, requires no electricity, no professional training, and is exceptionally portable for use in remote or home settings. This could be particularly useful in less industrialized areas. PMID:25393975

  11. GIANT PROSTHETIC VALVE THROMBUS

    Directory of Open Access Journals (Sweden)

    Prashanth Kumar

    2015-04-01

    Full Text Available Mechanical prosthetic valves are predisposed to bleeding, thrombosis & thromboembolic complications. Overall incidence of thromboembolic complications is 1% per year who are on oral anticoagulants, whereas bleeding complications incidence is 0.5% to 6.6% per year. 1, 2 Minimization of Scylla of thromboembolic & Charybdis of bleeding complication needs a balancing act of optimal antithrombotic therapy. We are reporting a case of middle aged male patient with prosthetic mitral valve presenting in heart failure. Patient had discontinued anticoagulants, as he had subdural hematoma in the past. He presented to our institute with a giant prosthetic valve thrombus.

  12. Prosthetics and Related Technology

    Science.gov (United States)

    ... forms of retinal blindness. Source: Boston Retinal Implant Project, funded in part by VA. VA Prosthetics Research ... their injuries. For questions or additional copies contact: R&D Communications (12) 103 South Gay Street, Ste. 517 ...

  13. Welding of Prosthetic Alloys

    OpenAIRE

    Wojciechowska M.; Wołowiec E.; Klimek L.

    2015-01-01

    This paper presents the techniques of joining metal denture elements, used in prosthetic dentistry: the traditional soldering technique with a gas burner and a new technique of welding with a laser beam; the aim of the study was to make a comparative assessment of the quality of the joints in view of the possibility of applying them in prosthetic structures. Fractographic examinations were conducted along with tensile strength and impact strength tests, and the quality of the joints was asses...

  14. Imprecise knowledge based design and development of titanium alloys for prosthetic applications.

    Science.gov (United States)

    Datta, S; Mahfouf, M; Zhang, Q; Chattopadhyay, P P; Sultana, N

    2016-01-01

    Imprecise knowledge on the composition-processing-microstructure-property correlation of titanium alloys combined with experimental data are used for developing rule based models for predicting the strength and elastic modulus of titanium alloys. The developed models are used for designing alloys suitable for orthopedic and dental applications. Reduced Space Searching Algorithm is employed for the multi-objective optimization to find composition, processing and microstructure of titanium alloys suitable for orthopedic applications. The conflicting requirements attributes of the alloys for this particular purpose are high strength with low elastic modulus, along with adequate biocompatibility and low costs. The 'Pareto' solutions developed through multi-objective optimization show that the preferred compositions for the fulfilling the above objectives lead to β or near β-alloys. The concept of decision making employed on the solutions leads to some compositions, which should provide better combination of the required attributes. The experimental development of some of the alloys has been carried out as guided by the model-based design methodology presented in this research. Primary characterizations of the alloys show encouraging results in terms of the mechanical properties. PMID:26398780

  15. Semiconductor-based, large-area, flexible, electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Amit (Knoxville, TN)

    2011-03-15

    Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  16. Prosthetic Valve Thrombosis: Diagnosis and Management.

    Science.gov (United States)

    Garg, Jalaj; Palaniswamy, Chandrasekar; Pinnamaneni, Sowmya; Sarungbam, Judy; Jain, Diwakar

    2016-01-01

    St. Jude mechanical prosthesis is the most commonly used prosthetic device with least valvular complications with excellent hemodynamics. However, prosthetic valve thrombosis is one of the serious complications, with rates between 0.03% and 0.13% per patient-year depending on the type of anticoagulation used and compliance to the therapy. Transthoracic echocardiography (TTE) is the initial screening tool (class I) that would provide clues for the assessment of valvular hemodynamics. Fluoroscopy is an alternate imaging modality for the assessment of mechanical leaflet motion, especially in patients when prosthetic valves are difficult to image on TTE or transesophageal echocardiography. A complete fluoroscopic evaluation of a prosthetic valve includes assessment of valvular motion and structural integrity. Opening and closing angles can be measured fluoroscopically to determine whether a specific valve is functioning properly. We discuss a case of a 91-year-old man with thrombosis of bileaflet mechanical mitral prosthesis that was demonstrated on real-time fluoroscopy (not evident on TTE). An algorithmic approach to diagnosis and management of prosthetic heart valve thrombosis is outlined. PMID:25486519

  17. Amorphous silicon based betavoltaic devices

    OpenAIRE

    Wyrsch, N; Riesen, Y.; Franco, A; S. Dunand; Kind, H.; Schneider, S.; Ballif, C.

    2013-01-01

    Hydrogenated amorphous silicon betavoltaic devices are studied both by simulation and experimentally. Devices exhibiting a power density of 0.1 μW/cm2 upon Tritium exposure were fabricated. However, a significant degradation of the performance is taking place, especially during the first hours of the exposure. The degradation behavior differs from sample to sample as well as from published results in the literature. Comparisons with degradation from beta particles suggest an effect of tritium...

  18. Energy Harvesting. Energy harvesting with prosthetic feet

    OpenAIRE

    Gunnar Páll Halldórsson 1990

    2016-01-01

    This thesis reviews the principles and state-of-art of miniature energy harvesting systems and how they can be a suitable application for powering low-power wireless electronic devices used in prosthetic legs by the company Össur. There is an expansion in wireless sensors networks and the development of low power consumption devices has created a field for researching micro-generators converting ambient energy into electricity to replace batteries that require costly maintenance. By harvestin...

  19. Prosthetic prescription in the Netherlands: An interview with clinical experts

    NARCIS (Netherlands)

    Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; van Limbeek, Jonice; Postema, K.

    2004-01-01

    In the process of guideline development for prosthetic prescription in the Netherlands the authors made a study of the daily clinical practice of lower limb prosthetics. Besides the evidence-based knowledge from literature the more implicit knowledge from clinical experts is of importance for guidel

  20. Recombinant protein-based nanoscale biomemory devices.

    Science.gov (United States)

    Yagati, A K; Min, J; Choi, J W

    2014-01-01

    Biomolecular computing devices that are based on the properties of biomolecular activities offer a unique possibility for constructing new computing structures. A new concept of using various biomolecules has been proposed in order to develop a protein-based memory device that is capable of switching physical properties when electrical input signals are applied to perform memory switching. To clarify the proposed concept, redox protein is immobilized on Au nanoelectrodes to catalyze reversible reactions of redox-active molecules, which is controlled electrochemically and reversibly converted between its ON/OFF states. In this review, we summarize recent research towards developing nanoscale biomemory devices including design, synthesis, fabrication, and functionalization based on the proposed concept. At first we analyze the memory function properties of the proposed device at bulk material level and then explain the WORM (write-once-read-many times) nature of the device, later we extend the analysis to multi-bit and multi-level storage functions, and then we focus the developments in nanoscale biomemory devices based on the electron transport of redox molecules to the underlying Au patterned surface. The developed device operates at very low voltages and has good stability and excellent reversibility, proving to be a promising platform for future memory devices. PMID:24730273

  1. Adaptive Device Context Based Mobile Learning Systems

    Science.gov (United States)

    Pu, Haitao; Lin, Jinjiao; Song, Yanwei; Liu, Fasheng

    2011-01-01

    Mobile learning is e-learning delivered through mobile computing devices, which represents the next stage of computer-aided, multi-media based learning. Therefore, mobile learning is transforming the way of traditional education. However, as most current e-learning systems and their contents are not suitable for mobile devices, an approach for…

  2. Welding of Prosthetic Alloys

    Directory of Open Access Journals (Sweden)

    Wojciechowska M.

    2015-04-01

    Full Text Available This paper presents the techniques of joining metal denture elements, used in prosthetic dentistry: the traditional soldering technique with a gas burner and a new technique of welding with a laser beam; the aim of the study was to make a comparative assessment of the quality of the joints in view of the possibility of applying them in prosthetic structures. Fractographic examinations were conducted along with tensile strength and impact strength tests, and the quality of the joints was assessed compared to the solid metal. The experiments have shown that the metal elements used to make dentures, joined by the technique which employs a laser beam, have better strength properties than those achieved with a gas burner.

  3. Biomaterials-Based Organic Electronic Devices

    Science.gov (United States)

    Bettinger, Christopher J.; Bao, Zhenan

    2010-01-01

    Organic electronic devices have demonstrated tremendous versatility in a wide range of applications including consumer electronics, photovoltaics, and biotechnology. The traditional interface of organic electronics with biology, biotechnology, and medicine occurs in the general field of sensing biological phenomena. For example, the fabrication of hybrid electronic structures using both organic semiconductors and bioactive molecules has led to enhancements in sensitivity and specificity within biosensing platforms, which in turn has a potentially wide range of clinical applications. However, the interface of biomolecules and organic semiconductors has also recently explored the potential use of natural and synthetic biomaterials as structural components of electronic devices. The fabrication of electronically active systems using biomaterials-based components has the potential to realize a large set of unique devices including environmentally biodegradable systems and bioresorbable temporary medical devices. This article reviews recent advances in the implementation of biomaterials as structural components in organic electronic devices with a focus on potential applications in biotechnology and medicine. PMID:20607127

  4. Development of prosthetic skin

    Science.gov (United States)

    Kilaru, Rohit

    The objective of this research was to embed tactile sensors in polyimides. This novel method could be utilized to realize prosthetic skin for sensing different kinds of mechanical stimuli. Tactile sensors have an increasing demand in medical sectors: upper and lower-limb prosthetics and in the industrial sectors: robot end-effectors, grippers and manipulators. The sensors developed are targeted for prosthetic arm tactile sensing applications. Current work presents piezoresistive differential pressure sensors fabricated on flexible polyimide film or substrate. A unique technique to bond a flexible superstrate polyimide layer to a MEMS tactile sensor array is presented in this thesis. The sensor is made of aluminium oxide membrane layer with nichrome piezoresistors as the half-Wheatstone bridge elements. Four different types of sensor designs have been characterized to obtain gauge factor of thin film nichrome. The sensor arrays with and without the superstrate film were simulated for obtaining the maximum stress, average strain and deflection of the membrane. The maximum change in output voltage was 0.8 mV. The gauge factors calculated for tactile sensor with superstrate range between 2.2 to 7.8 and without superstrate range 1.5 to 5.7.

  5. Dynamic Facial Prosthetics for Sufferers of Facial Paralysis

    Directory of Open Access Journals (Sweden)

    Fergal Coulter

    2011-10-01

    Full Text Available BackgroundThis paper discusses the various methods and the materialsfor the fabrication of active artificial facial muscles. Theprimary use for these will be the reanimation of paralysedor atrophied muscles in sufferers of non-recoverableunilateral facial paralysis.MethodThe prosthetic solution described in this paper is based onsensing muscle motion of the contralateral healthy musclesand replicating that motion across a patient’s paralysed sideof the face, via solid state and thin film actuators. Thedevelopment of this facial prosthetic device focused onrecreating a varying intensity smile, with emphasis ontiming, displacement and the appearance of the wrinklesand folds that commonly appear around the nose and eyesduring the expression.An animatronic face was constructed with actuations beingmade to a silicone representation musculature, usingmultiple shape-memory alloy cascades. Alongside theartificial muscle physical prototype, a facial expressionrecognition software system was constructed. This formsthe basis of an automated calibration and reconfigurationsystem for the artificial muscles following implantation, soas to suit the implantee’s unique physiognomy.ResultsAn animatronic model face with silicone musculature wasdesigned and built to evaluate the performance of ShapeMemory Alloy artificial muscles, their power controlcircuitry and software control systems. A dual facial motionsensing system was designed to allow real time control overmodel – a piezoresistive flex sensor to measure physicalmotion, and a computer vision system to evaluate real toartificial muscle performance.Analysis of various facial expressions in real subjects wasmade, which give useful data upon which to base thesystems parameter limits.ConclusionThe system performed well, and the various strengths andshortcomings of the materials and methods are reviewedand considered for the next research phase, when newpolymer based artificial muscles are constructed

  6. Progress of Terahertz Devices Based on Graphene

    Institute of Scientific and Technical Information of China (English)

    Mai-Xia Fu; Yan Zhang

    2013-01-01

    Graphene is a one-atom-thick planar sheet of sp2-hybridized orbital bonded honeycomb carbon crystal. Its gapless and linear energy spectra of electrons and holes lead to the unique carrier transport and optical properties, such as giant carrier mobility and broadband flat optical response. As a novel material, graphene has been regarded to be extremely suitable and competent for the development of terahertz (THz) optical devices. In this paper, the fundamental electronic and optic properties of graphene are described. Based on the energy band structure and light transmittance properties of graphene, many novel graphene based THz devices have been proposed, including modulator, generator, detector, and imaging device. This progress has been reviewed. Future research directions of the graphene devices for THz applications are also proposed.

  7. JRRD Then & Now: VA Prosthetic and Sensory Aids Service—65 Years of Progress

    OpenAIRE

    Lucille Beck, PhD

    2013-01-01

    The JRRD article written by Stewart in 1965 entitled “Twenty Years of Progress” highlighted the progress of the Veteran Administration’s Prosthetic and Sensory Aids Service since World War II. Recognizing the importance of prosthetic and sensory aids to Veteran healthcare during those early days set the foundation for the department of today to become the largest and most comprehensive provider of prosthetic devices and sensory aids in the world.

  8. Torsion based universal MEMS logic device

    KAUST Repository

    Ilyas, Saad

    2015-10-28

    In this work we demonstrate torsion based complementary MEMS logic device, which is capable, of performing INVERTER, AND, NAND, NOR, and OR gates using one physical structure within an operating range of 0-10 volts. It can also perform XOR and XNOR with one access inverter using the same structure with different electrical interconnects. The paper presents modeling, fabrication and experimental calculations of various performance features of the device including lifetime, power consumption and resonance frequency. The fabricated device is 535 μm by 150 μm with a gap of 1.92 μm and a resonant frequency of 6.51 kHz. The device is capable of performing the switching operation with a frequency of 1 kHz.

  9. Wide band-gap nanostructure based devices

    OpenAIRE

    Chen, Xinyi; 陈辛夷

    2012-01-01

    Wide band gap based nanostructures have being attracting much research interest because of their promise for application in optoelectronic devices. Among those wide band gap semiconductors, gallium nitride (GaN) and zinc oxide (ZnO) are the most commonly studied and optoelectronic devices based on GaN and ZnO have been widely investigated. This thesis concentrates on the growth, optical and electrical properties of GaN and ZnO nanostructures, plus their application in solar cells and light e...

  10. Carbon Nanotube Paper-Based Electroanalytical Devices

    OpenAIRE

    Youngmi Koo; Vesselin N. Shanov; Yeoheung Yun

    2016-01-01

    Here, we report on carbon nanotube paper-based electroanalytical devices. A highly aligned-carbon nanotube (HA-CNT) array, grown using chemical vapor deposition (CVD), was processed to form bi-layered paper with an integrated cellulose-based Origami-chip as the electroanalytical device. We used an inverse-ordered fabrication method from a thick carbon nanotube (CNT) sheet to a thin CNT sheet. A 200-layered HA-CNT sheet and a 100-layered HA-CNT sheet are explored as a working electrode. The de...

  11. Prosthetic elbow joint

    Science.gov (United States)

    Weddendorf, Bruce C. (Inventor)

    1994-01-01

    An artificial, manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic is described. The prosthesis provides a locking feature that is easily controlled by the wearer. The instant elbow joint is very strong and durable enough to withstand the repeated heavy loadings encountered by a wearer who works in an industrial, construction, farming, or similar environment. The elbow joint of the present invention comprises a turntable, a frame, a forearm, and a locking assembly. The frame generally includes a housing for the locking assembly and two protruding ears. The forearm includes an elongated beam having a cup-shaped cylindrical member at one end and a locking wheel having a plurality of holes along a circular arc on its other end with a central bore for pivotal attachment to the protruding ears of the frame. The locking assembly includes a collar having a central opening with a plurality of internal grooves, a plurality of internal cam members each having a chamfered surface at one end and a V-shaped slot at its other end; an elongated locking pin having a crown wheel with cam surfaces and locking lugs secured thereto; two coiled compression springs; and a flexible filament attached to one end of the elongated locking pin and extending from the locking assembly for extending and retracting the locking pin into the holes in the locking wheel to permit selective adjustment of the forearm relative to the frame. In use, the turntable is affixed to the upper arm part of the prosthetic in the conventional manner, and the cup-shaped cylindrical member on one end of the forearm is affixed to the forearm piece of the prosthetic in the conventional manner. The elbow joint is easily adjusted and locked between maximum flex and extended positions.

  12. Human-Machine Interface for the Control of Multi-Function Systems Based on Electrocutaneous Menu: Application to Multi-Grasp Prosthetic Hands.

    Directory of Open Access Journals (Sweden)

    Jose Gonzalez-Vargas

    Full Text Available Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI cannot easily accommodate the system's complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns and/or the user has a considerable impairment (limited number of available signal sources. In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate, decoding (one signal to recognize, and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair, or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces in order to improve the usability of existing low

  13. 21 CFR 872.3710 - Base metal alloy.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Base metal alloy. 872.3710 Section 872.3710 Food... DEVICES DENTAL DEVICES Prosthetic Devices § 872.3710 Base metal alloy. (a) Identification. A base metal alloy is a device composed primarily of base metals, such as nickel, chromium, or cobalt, that...

  14. Upper extremity myoelectric prosthetics.

    Science.gov (United States)

    Uellendahl, J E

    2000-08-01

    Myoelectric control of upper limb prostheses has proven to be an effective and efficient means of controlling prosthetic components. This means of control has been used extensively for over 30 years, during which time these systems have become reliable and durable in most situations. Myoelectric control, or any other prosthetic control scheme, should not be considered as the optimal control for arm prostheses, but rather as one of the several effective ways of producing desired function. Advanced clinical practice calls for a blending of all control schemes, as appropriate, to allow the prosthesis to serve the intentions of the user efficiently and with little mental effort. Technology continues to change, bringing with it new and sometimes better ways of fitting amputees. Microprocessors and programmable controllers have opened new and exciting avenues for improvement in function. New, and as of yet unidentified, electronic and mechanical advances are certainly on the horizon. There is much work to be done before upper limb prostheses rightfully are called arm replacements. But progress is occurring and advances are being made toward the goal of replacing the function and appearance of that marvelous tool, the human arm. PMID:10989484

  15. 77 FR 14989 - Medicare Program; Revisions to the Durable Medical Equipment, Prosthetics, Orthotics, and...

    Science.gov (United States)

    2012-03-14

    ... replacement of such devices, and including one pair of conventional eyeglasses or contact lenses furnished subsequent to each cataract surgery with insertion of an intraocular lens. Other examples of prosthetic... equipment include blood glucose monitors, hospital beds, oxygen tents, and wheelchairs. Prosthetic...

  16. Client Device Based Content Adaptation Using Rule Base

    Directory of Open Access Journals (Sweden)

    Velammal

    2011-01-01

    Full Text Available Problem statement: Content adaptation have been playing an important role in mobile devices, wherein the content display differs from desktop computers in many aspects, such as display screens, processing power, network connection bandwidth. In order to display web contents appropriately on mobile devices and on other types of devices such as hand computers, PDAs, Smart phones, it is important to adapt or transcode them to fit the characteristics of these devices. Approach: Existing content adaptation systems deploy various techniques which have been developed for specific purposes and goals. By exploiting various possible combinations of available resources, appropriate adaptation process can be carried over on the actual data, so that the information can be assimilated in a different end system other than the intended system. In this study, we present a content adaptation system based on rules created for mobile devices. Rules are invoked based on the individual client device information. Results: The adaptation has been performed according to the delivery device which was formalized through the profiler system. A profile holds information about the hardware and software specifications of the device thereby enabling the adaption of web content based on their characteristics which enables the user to access the web easily on various devices. Conclusion/Recommendation: This study enhances the viability of the information being presented to user, which will be independent of the end system being used for accessing the information. With the help of configurable rules, effective content adaptation can be achieved to provide optimal result.

  17. Nanoscale Properties of Neural Cell Prosthetic and Astrocyte Response

    Science.gov (United States)

    Flowers, D. A.; Ayres, V. M.; Delgado-Rivera, R.; Ahmed, I.; Meiners, S. A.

    2009-03-01

    Preliminary data from in-vivo investigations (rat model) suggest that a nanofiber prosthetic device of fibroblast growth factor-2 (FGF-2)-modified nanofibers can correctly guide regenerating axons across an injury gap with aligned functional recovery. Scanning Probe Recognition Microscopy (SPRM) with auto-tracking of individual nanofibers is used for investigation of the key nanoscale properties of the nanofiber prosthetic device for central nervous system tissue engineering and repair. The key properties under SPRM investigation include nanofiber stiffness and surface roughness, nanofiber curvature, nanofiber mesh density and porosity, and growth factor presentation and distribution. Each of these factors has been demonstrated to have global effects on cell morphology, function, proliferation, morphogenesis, migration, and differentiation. The effect of FGF-2 modification on the key nanoscale properties is investigated. Results from the nanofiber prosthetic properties investigations are correlated with astrocyte response to unmodified and FGF-2 modified scaffolds, using 2D planar substrates as a control.

  18. Carbon Nanotube Paper-Based Electroanalytical Devices

    Directory of Open Access Journals (Sweden)

    Youngmi Koo

    2016-04-01

    Full Text Available Here, we report on carbon nanotube paper-based electroanalytical devices. A highly aligned-carbon nanotube (HA-CNT array, grown using chemical vapor deposition (CVD, was processed to form bi-layered paper with an integrated cellulose-based Origami-chip as the electroanalytical device. We used an inverse-ordered fabrication method from a thick carbon nanotube (CNT sheet to a thin CNT sheet. A 200-layered HA-CNT sheet and a 100-layered HA-CNT sheet are explored as a working electrode. The device was fabricated using the following methods: (1 cellulose-based paper was patterned using a wax printer, (2 electrical connection was made using a silver ink-based circuit printer, and (3 three electrodes were stacked on a 2D Origami cell. Electrochemical behavior was evaluated using electrochemical impedance spectroscopy (EIS and cyclic voltammetry (CV. We believe that this platform could attract a great deal of interest for use in various chemical and biomedical applications.

  19. Carbon-nanotube-based photonic devices

    Science.gov (United States)

    Yamashita, Shinji

    2007-11-01

    We recently proposed and demonstrated a saturable absorber (SA) incorporating carbon nanotube (CNT). CNT-based SA offers several key advantages such as: ultra-fast recovery time, polarization insensitivity, high optical damage threshold, mechanical and environmental robustness, chemical stability, and the ability to operate at wide range of wavelength bands. Using the CNT-based SA, we have realized femtosecond fiber pulsed lasers at various wavelengths, as well as the very short-cavity fiber laser having high repetition rate. Besides the saturable absorption, CNT has been shown to have high third-order nonlinearity, which is also attractive for realization of compact and integrated functional photonic devices, such as all-optical switches and wavelength converters. In this paper, we first present photonic properties of CNTs, and review our studies on CNT-based mode-locked fiber lasers. We also refer to fabrication methods of CNT-based photonic devices. We show our recent research progresses on novel photonic devices using evanescent coupling between optical field and CNT.

  20. ORAL HYGIENE OF PROSTHETIC DENTURE USER IN KODINGARENG ISLAND

    OpenAIRE

    NUR, NURUL KUSUMADEWI S.KG

    2008-01-01

    Objectives:to determine the level of oral hygiene for prosthetic denture user, especially for full-denture in Kodingareng Island. This researchincluded the distribution level of prosthetic denture user based on age and education.Methods: the method that used in this research is observational descriptive withcross sectional-studyas the research design. Variable result of the research determined in to 3, those are bad, middle, and good. Result:the highest percentage o...

  1. Nonvolatile memory devices based on self-assembled nanocrystals

    Science.gov (United States)

    Lee, Jang-Sik

    2013-06-01

    Nonvolatile memory devices are one of the most important components in modern electronic devices. Many efforts have been made to fabricate high-density, low-cost, nonvolatile solid-state memory devices for use in portable/mobile electronic devices such as laptop computers, tablet devices, smart phones, etc. Among the many available nonvolatile memory devices, flash memory devices are of great interest to the electronics industry owing to their simple device structure, enabling high-density memory applications. Flash memory devices in which nanoparticles or nanocrystals are used as the charge-trapping elements have advantages over conventional flash memory devices because the charge-trapping layer and memory performance of the former can be readily optimized. Active research has recently been conducted to fabricate and characterize self-assembled-nanocrystal-based nonvolatile memory devices. We reviewed various strategies for fabricating nanocrystal-based nonvolatile memory devices and discussed the programmable memory properties and the device reliability characteristics of nanocrystal-based memory devices to possibly apply nanocrystal-based memory devices to those used in portable/mobile electronic devices. Finally, novel device applications such as printed/flexible/transparent electronic devices were explored based on nanocrystal-based memory devices.

  2. Optimization-Based Design of a Small Pneumatic-Actuator-Driven Parallel Mechanism for a Shoulder Prosthetic Arm with Statics and Spatial Accessibility Evaluation

    Directory of Open Access Journals (Sweden)

    Masashi Sekine

    2013-07-01

    Full Text Available Human arms undertake most tasks in the activities of daily living (ADLs. When designing shoulder prostheses for high‐level upper‐limb amputees, we should consider not only how to realize high degrees of freedom under weight and shape constraints but also the user’s individual task space in daily life. An appropriate mechanical structure that can make full use of state‐of‐the‐art actuators and a scheme to optimize the structure’s configuration to match users’ spatial access and manipulability requirements are essential. In our previous research, a small pneumatic‐actuator‐driven parallel mechanism was studied as a shoulder prosthetic arm. In this paper, a systematic procedure is proposed to design the mechanism for a shoulder prosthesis considering force and spatial accessibility. This procedure includes ADL measurements to obtain the task spaces for individual subjects, indexes to evaluate the force and spatial accessibility and an optimization process based on kinematic and statics models. With this approach, the parallel mechanism was optimized for one important ADL task group, considering the trade‐off between its required force and working space. Moreover, it was confirmed that the proposed design procedure could find solutions for various spatial specifications. That is, the approach could be used for individualized shoulder prosthesis design.

  3. Double-gated graphene-based devices

    International Nuclear Information System (INIS)

    We discuss transport through double-gated single- and few-layer graphene devices. This kind of device configuration has been used to investigate the modulation of the energy band structure through the application of an external perpendicular electric field, a unique property of few-layer graphene systems. Here we discuss technological details that are important for the fabrication of top-gated structures, based on electron-gun evaporation of SiO2. We perform a statistical study that demonstrates how-contrary to expectations-the breakdown field of electron-gun evaporated thin SiO2 films is comparable to that of thermally grown oxide layers. We find that a high breakdown field can be achieved in evaporated SiO2 only if the oxide deposition is directly followed by metallization of the top electrodes, without exposure of the SiO2 layer to air.

  4. Recent advancements in prosthetic hand technology.

    Science.gov (United States)

    Saikia, Angana; Mazumdar, Sushmi; Sahai, Nitin; Paul, Sudip; Bhatia, Dinesh; Verma, Suresh; Rohilla, Punit Kumar

    2016-07-01

    Recently, significant advances over the past decade have been made in robotics, artificial intelligence and other cognitive related fields, allowing development of highly sophisticated bio-mimetic robotics systems. In addition, enormous number of robots have been designed and assembled by explicitly realising their biological oriented behaviours. To enhance skill behaviours and adequate grasping abilities in these devices, a new phase of dexterous hands has been developed recently with bio-mimetically oriented and bio-inspired functionalities. The aim in writing this review paper is to present a detailed insight towards the development of the bio-mimetic based dexterous robotic multi-fingered artificial hand. An "ideal" upper limb prosthesis should be perceived as a part of their natural body by the amputee and should replicate sensory-motor capabilities of the amputated limb. Upper-limb amputations are most often the result of sudden trauma to the body, although they also can be caused by malignancy, congenital deficiencies and vascular diseases. This paper discusses the different bio-mimetic approaches using a framework that permits for a common description of biological and technical based hand manipulation behaviour. In particular, the review focuses on a number of developments in the inspired robotic systems. In conclusion, the study found that a huge amount of research efforts in terms of kinematics, dynamics, modelling and control methodologies are being put in to improve the present hand technology, thereby providing more functionality to the prosthetic limb of the amputee. This would improve their quality-of-life and help in performing activities of daily living (ADL) tasks with comparative ease in the near future. PMID:27098838

  5. Pre-prosthetic surgery: Mandible

    OpenAIRE

    Veeramalai Naidu Devaki; Kandasamy Balu; Sadashiva Balakrishnapillai Ramesh; Ramraj Jayabalan Arvind; Venkatesan

    2012-01-01

    Pre-prosthetic surgery is that part of oral and maxillofacial surgery which restores oral function and facial form. This is concerned with surgical modification of the alveolar process and its surrounding structures to enable the fabrication of a well-fitting, comfortable, and esthetic dental prosthesis. The ultimate goal of pre-prosthetic surgery is to prepare a mouth to receive a dental prosthesis by redesigning and smoothening bony edges.

  6. [Prosthetic dental alloys. 1].

    Science.gov (United States)

    Quintero Engelmbright, M A

    1990-11-01

    A wide variety of restoration materials for prosthetic odontology is now available to the dental surgeon, either of the covalent type (acrylic resins), metallic (alloys), ionic (porcelains), or a combination of them, as in the so-called composites, such as the composite resins, or as ceramics-metals mixtures. An example of the latter is a product called Miracle-Mix, a glass ionomere cement reinforced with an amalgam alloy. In those cases where the blend is done by a synterization process, the material is called Cermet. The above-listed alternatives clearly evidence day-to-day advances in odontology, with researchers and manufacturers engaged the world over in improving existing products or developing new ones to enrich the dentist's armamentarium. As a side effect of this constant renewal, those dentists who have failed to update their knowledge fall behind in their practice as they persist in using products they have known for years, and may be deceived by advertisements of too-often unreliable products. It is, therefore, important to be aware of available products and their latest improvements. PMID:2132464

  7. [Prosthetic dental alloys (2)].

    Science.gov (United States)

    Quintero Englembright, M A

    1990-12-01

    A wide variety of restoration materials for prosthetic odontology is now available to the dental surgeon, either of the covalent type (acrylic resins), metallic (alloys), ionic (porcelains), or a combination of them, as in the so-called composites, such as the composite resins, or as ceramics-metals mixtures. An example of the latter is a product called Miracle-Mix, a glass ionomere cement reinforced with an amalgam alloy. In those cases where the blend is done by a synterization process, the material is called Cermet. The above-listed alternatives clearly evidence day-to-day advances in odontology, with researchers and manufacturers engaged the world over in improving existing products or developing new ones to enrich the dentist's armamentarium. As a side effect of this constant renewal, those dentists who have failed to update their knowledge fall behind in their practice as they persist in using products they have known for years, and may be deceived by advertisements of too-often unreliable products. It is, therefore, important to be aware of available products and their latest improvements. PMID:2132470

  8. YBCO based multilayers for optoelectronic devices

    International Nuclear Information System (INIS)

    YBCO based multilayers have been deposited independently by three techniques: laser ablation, inverted cylindrical target sputtering (ICM) and on-axis planar D.C. Magnetron Sputtering. The last technique is used to cover uniformly R-plane sapphire and LaAlO3 2 inch wafers with YBCO or multilayers to achieve optoelectronic devices such as infrared detectors. Very thin (- 3 nm) YSZ and MgO dielectric films have been studied as tunnel barriers for making such high Tc tunnel junctions. 14 refs., 11 figs

  9. Multiparametric electronic devices based on nuclear tracks

    Energy Technology Data Exchange (ETDEWEB)

    Fink, D. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany)], E-mail: FINK@HMI.DE; Saad, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Basic Science Department, Faculty of Science, Al Balqa University, Salt (Jordan); Dhamodaran, S. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); School of Physics, University of Hyderabad, Hyderabad 500 046 (India); Chandra, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Fahrner, W.R. [Chair of Electronic Devices, Institute of Electrotechnique, Fernuniversitaet, Hagen (Germany); Hoppe, K. [South Westfalia University of Applied Sciences, Hagen (Germany); Chadderton, L.T. [Institute of Advanced Studies, ANU Canberra, GPO Box 4, ACT (Australia)

    2008-08-15

    An overview is given on a family of novel electronic devices consisting of an insulating layer containing conducting or semiconducting nuclear tracks, deposited on a semiconducting substrate, and connected by at least one back and two surface contacts. Conducting and semiconducting latent tracks may emerge directly from swift heavy ion irradiation. Etched tracks in insulators can be filled with adequate materials to make them conducting or semiconducting. For this purpose metallic or semiconducting nanoclusters were deposited. We have denoted termed these devices made with latent tracks as 'tunable electronic anisotropic material on semiconductor' (TEAMS), if based on latent ion tracks, and as 'tunable electronic material in pores in oxide on semiconductor' (TEMPOS), if based on etched tracks. Depending on the band-to-band transition between tracks and substrate and on the ratio of surface to track conductivity, the current/voltage characteristics of TEAMS and TEMPOS structures can be modified in many different ways leading to tunable resistors, capacitors and diodes. Both devices show negative differential resistances. This should enable tunable tunneldiodes. TEAMS or TEMPOS structures can be controlled by various external physical and/or chemical parameters leading to sensors. It is even possible to combine different input currents and/or external parameters according to AND/OR logics. The currents through a clustered layer on a TEMPOS structure can be described by the Barbasi-Albert model of network theory enabling to calculate a 'radius of influence'r{sub ROI} around each surface contact, beyond which neighboring contacts do not influence each other. The radius of influence can be well below 1{mu}m leading to nanometric TEMPOS structures.

  10. EDITORIAL: Frontiers in semiconductor-based devices Frontiers in semiconductor-based devices

    Science.gov (United States)

    Krishna, Sanjay; Phillips, Jamie; Ghosh, Siddhartha; Ma, Jack; Sabarinanthan, Jayshri; Stiff-Roberts, Adrienne; Xu, Jian; Zhou, Weidong

    2009-12-01

    This special cluster of Journal of Physics D: Applied Physics reports proceedings from the Frontiers in Semiconductor-Based Devices Symposium, held in honor of the 60th birthday of Professor Pallab Bhattacharya by his former doctoral students. The symposium took place at the University of Michigan, Ann Arbor on 6-7 December 2009. Pallab Bhattacharya has served on the faculty of the Electrical Engineering and Computer Science Department at the University of Michigan, Ann Arbor for 25 years. During this time, he has made pioneering contributions to semiconductor epitaxy, characterization of strained heterostructures, self-organized quantum dots, quantum-dot optoelectronic devices, and integrated optoelectronics. Professor Bhattacharya has been recognized for his accomplishments by membership of the National Academy of Engineering, by chaired professorships (Charles M Vest Distinguished University Professor and James R Mellor Professor of Engineering), and by selection as a Fellow of the IEEE, among numerous other honors and awards. Professor Bhattacharya has also made remarkable contributions in education, including authorship of the textbook Semiconductor Optoelectronic Devices (Prentice Hall, 2nd edition) and the production of 60 PhD students (and counting). In fact, this development of critical human resources is one of the biggest impacts of Professor Bhattacharya's career. His guidance and dedication have shaped the varied professional paths of his students, many of whom currently enjoy successful careers in academia, industry, and government around the world. This special cluster acknowledges the importance of Professor Bhattacharya's influence as all of the contributions are from his former doctoral students. The symposium reflects the significant impact of Professor Bhattacharya's research in that the topics span diverse, critical research areas, including: semiconductor lasers and modulators, nanoscale quantum structure-based devices, flexible CMOS-based

  11. Blindness. [prosthetic devices and sensory aids

    Science.gov (United States)

    Pudenz, R. H.

    1974-01-01

    The possibilities are considered that modern electronics and engineering have to offer the individual with a damaged or disordered nervous system, especially the blind person. Discussed are the incidence and principal causes of blindness, past research activities, and a capsule review of some of the more interesting programs designed to provide the blind with the ability to be mobile in their environment and to read printed matter.

  12. Toxicology of antimicrobial nanoparticles for prosthetic devices

    OpenAIRE

    Nuñez-Anita, Rosa Elvira; Acosta-Torres, Laura Susana; Vilar-Pineda, Jorge; Martínez-Espinosa, Juan Carlos; de la Fuente-Hernández, Javier; Castaño, Víctor Manuel

    2014-01-01

    Advances in nanotechnology are producing an accelerated proliferation of new nanomaterial composites that are likely to become an important source of engineered health-related products. Nanoparticles with antifungal effects are of great interest in the formulation of microbicidal materials. Fungi are found as innocuous commensals and colonize various habitats in and on humans, especially the skin and mucosa. As growth on surfaces is a natural part of the Candida spp. lifestyle, one can expect...

  13. Prosthetic heart valves: Objective Performance Criteria versus randomized clinical trial.

    Science.gov (United States)

    Grunkemeier, Gary L; Jin, Ruyun; Starr, Albert

    2006-09-01

    The current Food and Drug Administration (FDA) heart valve guidance document uses an objective performance criteria (OPC) methodology to evaluate the clinical performance of prosthetic heart valves. OPC are essentially historical controls, but they have turned out to be an adequate, and perhaps optimal, study design in this situation. Heart valves have a simple open-and-close mechanism, device effectiveness is easy to document, and the common complications (thromboembolism, thrombosis, bleeding, leak, and infection) are well known and easily detected. Thus, randomized clinical trials (RCTs) have not been deemed necessary for the regulatory approval of prosthetic heart valves. The OPC are derived from the average complication rates of all approved heart valves. Studies based on OPC have been shown to work well; many different valve models have gained FDA market approval based on this methodology. Although heart valve RCTs are not required by the FDA, they have been done to compare valves or treatment regimens after approval. Recently, the Artificial Valve Endocarditis Reduction Trial (AVERT) was designed to compare a new Silzone sewing ring, designed to reduce infection, with the Standard sewing ring on a St. Jude Medical heart valve. This was the largest heart valve RCT ever proposed (4,400 valve patients, followed for as long as 4 years), but it was stopped prematurely because of a high leak rate associated with the Silzone valve. Examining the results showed that a much smaller, OPC-based study with 800 patient-years would have been sufficient to disclose this complication of the Silzone valve. PMID:16928482

  14. Consumer satisfaction with the services of prosthetics and orthotics facilities

    OpenAIRE

    Bosmans, Joline; Geertzen, Jan; Dijkstra, Pieter U.

    2009-01-01

    Consumer satisfaction with the services provided in a prosthetics and orthotics (PO) facility has seldom been studied. The aim of this study was to analyze consumer satisfaction regarding the services provided by 15 PO facilities in The Netherlands. Consumers (n=1,364) of these PO facilities who were fitted with a prosthesis, orthopaedic shoes, an orthosis, or another device, were asked to rate the overall services provided and whether they were satisfied with the device provided and its deli...

  15. Hybrid photovoltaic devices based on chalcogenide nanostructures

    Science.gov (United States)

    de Freitas, Jilian N.; Alves, João. Paulo C.; Korala, Lasantha; Brock, Stephanie L.; Nogueira, Ana F.

    2012-09-01

    Solar cells based on the combination of conjugated polymers and fullerenes are among the most promising devices for low-cost solar energy conversion. Significant improvements in the efficiency have been accomplished, but some bottlenecks still persist. The substitution of fullerenes by inorganic semiconductor nanoparticles, especially CdSe and CdS, has been investigated as a promising alternative. In this work, we highlight two aspects to be considered in the pursuit of more efficient devices. By comparing different polymer/CdSe systems, we show how the polymer structure can be used to tune the charge transfer from the polymer to CdSe. Even if this process is efficient, the charges will be trapped in the inorganic phase if the charge carrier transport of the nanoparticles is poor. An elegant way to improve the electron hopping is to form an electrically integrated network of nanoparticles. The use of chalcogenide aerogels is a new alternative which may be interesting for applications requiring maximal transport of charge and is also discussed here.

  16. Candida infection of a prosthetic shoulder joint

    International Nuclear Information System (INIS)

    A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole. (orig.)

  17. Integrating Android Devices into Network Management Systems based on SNMP

    OpenAIRE

    Fernando Hidalgo; Eric Gamess

    2014-01-01

    Mobile devices are becoming essential for today life. In developed countries, about half of the people have a smartphone, resulting in millions of these electronic devices. Android is the most popular operating system for smartphones and other electronic devices such as tablets. Hence, for network administrators, it is essential to start managing all the Android based devices. SNMP is the de facto standard for network administration, where agents that are running in managed devices are polled...

  18. Successful thrombolysis for prosthetic pulmonary valve obstruction.

    OpenAIRE

    Lopez, J. A.; Strickman, N E; Jin, B S; X. G. Li; Phan, B; Zeluff, B J; Wilansky, S

    1995-01-01

    Thrombosis is a serious complication of prosthetic heart valve operations. In recent years, systemic thrombolysis has emerged as a suitable alternative to surgery. Experience with thrombosis of pulmonary prosthetic valves is very limited. We report a case of successful administration of intravenous streptokinase for thrombosis of a St. Jude Medical prosthetic valve 3 weeks after pulmonary valve replacement.

  19. Critical components for diamond-based quantum coherent devices

    International Nuclear Information System (INIS)

    The necessary elements for practical devices exploiting quantum coherence in diamond materials are summarized, and progress towards their realization documented. A brief review of future prospects for diamond-based devices is also provided

  20. Development of superconducting interference device based on graphene

    International Nuclear Information System (INIS)

    We fabricated and examined the operation of graphene-based superconducting interference device (SQUID) consisting of two superconductor-single layer graphene-superconductor junctions connected in parallel on a superconducting loop made of aluminum. Current-voltage characteristic of the device exhibits supercurrent flowing through SGS junctions. Mean switching current can be modulated with the applied magnetic field periodically. Deduced oscillation period coincides well with that estimated from the device geometry, suggesting that our device works as a graphene-based SQUID.

  1. Development of superconducting interference device based on graphene

    Science.gov (United States)

    Tsumura, K.; Ohsugi, M.; Hayashi, T.; Watanabe, E.; Tsuya, D.; Nomura, S.; Takayanagi, H.

    2012-12-01

    We fabricated and examined the operation of graphene-based superconducting interference device (SQUID) consisting of two superconductor-single layer graphene-superconductor junctions connected in parallel on a superconducting loop made of aluminum. Current-voltage characteristic of the device exhibits supercurrent flowing through SGS junctions. Mean switching current can be modulated with the applied magnetic field periodically. Deduced oscillation period coincides well with that estimated from the device geometry, suggesting that our device works as a graphene-based SQUID.

  2. A Flexible Microcontroller-Based Data Acquisition Device

    OpenAIRE

    Darko Hercog; Bojan Gergič

    2014-01-01

    This paper presents a low-cost microcontroller-based data acquisition device. The key component of the presented solution is a configurable microcontroller-based device with an integrated USB transceiver and a 12-bit analogue-to-digital converter (ADC). The presented embedded DAQ device contains a preloaded program (firmware) that enables easy acquisition and generation of analogue and digital signals and data transfer between the device and the application running on a PC via USB bus. This d...

  3. Microfiber devices based on carbon materials

    Directory of Open Access Journals (Sweden)

    Gengzhi Sun

    2015-05-01

    Full Text Available Microfiber devices are able to extend the micro/nano functionalities of materials or devices to the macroscopic scale with excellent flexibility and weavability, promising a variety of unique applications and, sometimes, also improved performance as compared with bulk counterparts. The fiber electrodes in these devices are often made of carbon materials (e.g. carbon nanotubes and graphene because of their exceptional electrical, mechanical, and structural properties. Covering the latest developments and aiming to stimulate more exciting applications, we comprehensively review the preparation and applications of carbon-microfiber devices on energy conversion and storage, electronics, sensors and actuators.

  4. Semiconductor-based, large-area, flexible, electronic devices on {110}<100> oriented substrates

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Amit

    2014-08-05

    Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110}<100> textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  5. [100] or [110] aligned, semiconductor-based, large-area, flexible, electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Amit

    2015-03-24

    Novel articles and methods to fabricate the same resulting in flexible, large-area, [100] or [110] textured, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  6. {100} or 45.degree.-rotated {100}, semiconductor-based, large-area, flexible, electronic devices

    Science.gov (United States)

    Goyal, Amit

    2012-05-15

    Novel articles and methods to fabricate the same resulting in flexible, {100} or 45.degree.-rotated {100} oriented, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  7. Semiconductor-based, large-area, flexible, electronic devices on {110} oriented substrates

    Science.gov (United States)

    Goyal, Amit

    2014-08-05

    Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110} textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  8. Synaptic devices based on purely electronic memristors

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Ruobing [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Institute of Materials Science, School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Li, Jun; Zhuge, Fei, E-mail: zhugefei@nimte.ac.cn, E-mail: h-cao@nimte.ac.cn; Zhu, Liqiang; Liang, Lingyan; Zhang, Hongliang; Gao, Junhua; Cao, Hongtao, E-mail: zhugefei@nimte.ac.cn, E-mail: h-cao@nimte.ac.cn; Fu, Bing; Li, Kang [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2016-01-04

    Memristive devices have been widely employed to emulate biological synaptic behavior. In these cases, the memristive switching generally originates from electrical field induced ion migration or Joule heating induced phase change. In this letter, the Ti/ZnO/Pt structure was found to show memristive switching ascribed to a carrier trapping/detrapping of the trap sites (e.g., oxygen vacancies or zinc interstitials) in ZnO. The carrier trapping/detrapping level can be controllably adjusted by regulating the current compliance level or voltage amplitude. Multi-level conductance states can, therefore, be realized in such memristive device. The spike-timing-dependent plasticity, an important Hebbian learning rule, has been implemented in this type of synaptic device. Compared with filamentary-type memristive devices, purely electronic memristors have potential to reduce their energy consumption and work more stably and reliably, since no structural distortion occurs.

  9. Synaptic devices based on purely electronic memristors

    International Nuclear Information System (INIS)

    Memristive devices have been widely employed to emulate biological synaptic behavior. In these cases, the memristive switching generally originates from electrical field induced ion migration or Joule heating induced phase change. In this letter, the Ti/ZnO/Pt structure was found to show memristive switching ascribed to a carrier trapping/detrapping of the trap sites (e.g., oxygen vacancies or zinc interstitials) in ZnO. The carrier trapping/detrapping level can be controllably adjusted by regulating the current compliance level or voltage amplitude. Multi-level conductance states can, therefore, be realized in such memristive device. The spike-timing-dependent plasticity, an important Hebbian learning rule, has been implemented in this type of synaptic device. Compared with filamentary-type memristive devices, purely electronic memristors have potential to reduce their energy consumption and work more stably and reliably, since no structural distortion occurs

  10. Scope of Tunnel Junction Based Molecular Electronics and Spintronics Devices

    OpenAIRE

    Tyagi, Pawan; Friebe, Edwards; Baker, Collin

    2014-01-01

    Scope of molecule based devices may govern the advancement of the next generation logic and memory devices. Molecules have the potential to be unmatched device elements as chemists can mass produce an endless variety of molecules with novel optical, magnetic, and charge transport characteristics. However, the biggest challenge is to connect two metal leads to a target molecule(s) and develop a robust and versatile device fabrication technology that can be adopted for commercial scale mass pro...

  11. Thick film force and slip sensors for a prosthetic hand

    OpenAIRE

    Cranny, A; Cotton, D P J; Chappell, P H; White, N.M.

    2004-01-01

    In an attempt to improve the functionality of a prosthetic hand device, a new fingertip has been developed that incorporates sensors to measure temperature and grip force, and to detect the onset of object slip from the hand. The sensors have been implemented using thick film printing technology and exploit the piezoresistive characteristics of commercially available screen printing resistive pastes and the piezoelectric properties of proprietary lead-zirconate-titanate (PZT) formulated paste...

  12. Amputation and Prosthetics

    Science.gov (United States)

    ... Symptom Picker Hand and Arm Conditions Carpal Tunnel Ganglion Cysts Trigger Finger Arthritis Base of the Thumb See ... Symptom Picker Hand and Arm Conditions Carpal Tunnel Ganglion Cysts Trigger Finger Arthritis Base of the Thumb See ...

  13. Conducting polymer based biomolecular electronic devices

    Indian Academy of Sciences (India)

    B D Malhotra; Rahul Singhal

    2003-08-01

    Biomolecular electronics is rapidly evolving from physics, chemistry, biology, electronics and information technology. Organic materials such as proteins, pigments and conducting polymers have been considered as alternatives for carrying out the functions that are presently being performed by semiconductor silicon. Conducting polymers such as polypyrroles, polythiophenes and polyanilines have been projected for applications for a wide range of biomolecular electronic devices such as optical, electronic, drug-delivery, memory and biosensing devices. Our group has been actively working towards the application of conducting polymers to Schottky diodes, metal–insulator–semiconductor (MIS) devices and biosensors for the past 10 years. This paper is a review of some of the results obtained at our laboratory in the area of conducting polymer biomolecular electronics.

  14. Performance evaluation of cellular phone network based portable ECG device.

    Science.gov (United States)

    Hong, Joo-Hyun; Cha, Eun-Jong; Lee, Tae-Soo

    2008-01-01

    In this study, cellular phone network based portable ECG device was developed and three experiments were performed to evaluate the accuracy, reliability and operability, applicability during daily life of the developed device. First, ECG signals were measured using the developed device and Biopac device (reference device) during sitting and marking time and compared to verify the accuracy of R-R intervals. Second, the reliable data transmission to remote server was verified on two types of simulated emergency event using patient simulator. Third, during daily life with five types of motion, accuracy of data transmission to remote server was verified on two types of event occurring. By acquiring and comparing subject's biomedical signal and motion signal, the accuracy, reliability and operability, applicability during daily life of the developed device were verified. Therefore, cellular phone network based portable ECG device can monitor patient with inobtrusive manner. PMID:19162767

  15. Deep Feature-based Face Detection on Mobile Devices

    OpenAIRE

    Sarkar, Sayantan; Patel, Vishal M.; Chellappa, Rama

    2016-01-01

    We propose a deep feature-based face detector for mobile devices to detect user's face acquired by the front facing camera. The proposed method is able to detect faces in images containing extreme pose and illumination variations as well as partial faces. The main challenge in developing deep feature-based algorithms for mobile devices is the constrained nature of the mobile platform and the non-availability of CUDA enabled GPUs on such devices. Our implementation takes into account the speci...

  16. Brucella Endocarditis in Prosthetic Valves

    OpenAIRE

    Mehanic, Snjezana; Mulabdic, Velida; Baljic, Rusmir; Hadzovic-Cengic, Meliha; Pinjo, Fikret; Hadziosmanovic, Vesna; Topalovic, Jasna

    2012-01-01

    SUMMARY CONFLICT OF INTEREST: none declared. Introduction Brucella endocarditis (BE) is a rare but severe and potentially lethal manifestation of brucellosis. Pre-existing valves lesions and prosthetic valves (PV) are favorable for BE. Case report We represent the case of a 46-year-old man who was treated at the Clinic for Infectious Diseases, Clinical Center of Sarajevo University, as blood culture positive (Brucella melitensis) mitral and aortic PV endocarditis. He was treated with combined...

  17. Model-based engineering for medical-device software.

    Science.gov (United States)

    Ray, Arnab; Jetley, Raoul; Jones, Paul L; Zhang, Yi

    2010-01-01

    This paper demonstrates the benefits of adopting model-based design techniques for engineering medical device software. By using a patient-controlled analgesic (PCA) infusion pump as a candidate medical device, the authors show how using models to capture design information allows for i) fast and efficient construction of executable device prototypes ii) creation of a standard, reusable baseline software architecture for a particular device family, iii) formal verification of the design against safety requirements, and iv) creation of a safety framework that reduces verification costs for future versions of the device software. 1. PMID:21142522

  18. Animation Based Learning of Electronic Devices

    Science.gov (United States)

    Gero, Aharon; Zoabi, Wishah; Sabag, Nissim

    2014-01-01

    Two-year college teachers face great difficulty when they teach the principle of operation of the bipolar junction transistor--a subject which forms the basis for electronics studies. The difficulty arises from both the complexity of the device and by the lack of adequate scientific background among the students. We, therefore, developed a unique…

  19. A computational method for comparing the behavior and possible failure of prosthetic implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.; Hollerbach, K.; Perfect, S.; Underhill, K.

    1995-05-01

    Prosthetic joint implants currently in use exhibit high Realistic computer modeling of prosthetic implants provides an opportunity for orthopedic biomechanics researchers and physicians to understand possible in vivo failure modes, without having to resort to lengthy and costly clinical trials. The research presented here is part of a larger effort to develop realistic models of implanted joint prostheses. The example used here is the thumb carpo-metacarpal (cmc) joint. The work, however, can be applied to any other human joints for which prosthetic implants have been designed. Preliminary results of prosthetic joint loading, without surrounding human tissue (i.e., simulating conditions under which the prosthetic joint has not yet been implanted into the human joint), are presented, based on a three-dimensional, nonlinear finite element analysis of three different joint implant designs.

  20. Multimodality Imaging Assessment of Prosthetic Heart Valves.

    Science.gov (United States)

    Suchá, Dominika; Symersky, Petr; Tanis, W; Mali, Willem P Th M; Leiner, Tim; van Herwerden, Lex A; Budde, Ricardo P J

    2015-09-01

    Echocardiography and fluoroscopy are the main techniques for prosthetic heart valve (PHV) evaluation, but because of specific limitations they may not identify the morphological substrate or the extent of PHV pathology. Cardiac computed tomography (CT) and magnetic resonance imaging (MRI) have emerged as new potential imaging modalities for valve prostheses. We present an overview of the possibilities and pitfalls of CT and MRI for PHV assessment based on a systematic literature review of all experimental and patient studies. For this, a comprehensive systematic search was performed in PubMed and Embase on March 24, 2015, containing CT/MRI and PHV synonyms. Our final selection yielded 82 articles on surgical valves. CT allowed adequate assessment of most modern PHVs and complemented echocardiography in detecting the obstruction cause (pannus or thrombus), bioprosthesis calcifications, and endocarditis extent (valve dehiscence and pseudoaneurysms). No clear advantage over echocardiography was found for the detection of vegetations or periprosthetic regurgitation. Whereas MRI metal artifacts may preclude direct prosthesis analysis, MRI provided information on PHV-related flow patterns and velocities. MRI demonstrated abnormal asymmetrical flow patterns in PHV obstruction and allowed prosthetic regurgitation assessment. Hence, CT shows great clinical relevance as a complementary imaging tool for the diagnostic work-up of patients with suspected PHV obstruction and endocarditis. MRI shows potential for functional PHV assessment although more studies are required to provide diagnostic reference values to allow discrimination of normal from pathological conditions. PMID:26353926

  1. Retinal Prosthetics, Optogenetics, and Chemical Photoswitches

    OpenAIRE

    Marc, Robert; Pfeiffer, Rebecca; Jones, Bryan

    2014-01-01

    Three technologies have emerged as therapies to restore light sensing to profoundly blind patients suffering from late-stage retinal degenerations: (1) retinal prosthetics, (2) optogenetics, and (3) chemical photoswitches. Prosthetics are the most mature and the only approach in clinical practice. Prosthetic implants require complex surgical intervention and provide only limited visual resolution but can potentially restore navigational ability to many blind patients. Optogenetics uses viral ...

  2. Prosthetic finger phalanges with lifelike skin compliance for low-force social touching interactions

    CERN Document Server

    Cabibihan, John-John; Ge, Shuzhi Sam; 10.1186/1743-0003-8-16

    2011-01-01

    Prosthetic arms and hands that can be controlled by the user's electromyography (EMG) signals are emerging. Eventually, these advanced prosthetic devices will be expected to touch and be touched by other people. As realistic as they may look, the currently available prosthetic hands have physical properties that are still far from the characteristics of human skins because they are much stiffer. In this paper, different configurations of synthetic finger phalanges have been investigated for their skin compliance behaviour and have been compared with the phalanges of the human fingers and a phalanx from a commercially available prosthetic hand. Handshake tests were performed to identify which areas on the human hand experience high contact forces. After these areas were determined, experiments were done on selected areas using an indenting probe to obtain the force-displacement curves. Finite element simulations were used to compare the force-displacement results of the synthetic finger phalanx designs with th...

  3. Regulatory science based approach in development of novel medical devices.

    Science.gov (United States)

    Sakuma, Ichiro

    2015-08-01

    For development rational evaluation method for medical devices' safety and efficacy, regulatory science studies are important. Studies on regulatory affairs related to a medical device under development should be conducted as well as its technological development. Clinical performance of a medical device is influenced by performance of the device, medical doctors' skill, pathological condition of a patient, and so on. Thus it is sometimes difficult to demonstrate superiority of the device in terms of clinical outcome although its efficacy as a medical device is accepted. Setting of appropriate end points is required to evaluate a medical device appropriately. Risk assessment and risk management are the basis of medical device safety assurance. In case of medical device software, there are difficulties in identifying the risk due to its complexity of user environment and different design and manufacturing procedure compared with conventional hardware based medical devices. Recent technological advancement such as information and communication technologies (ICT) for medical devices and wireless network has raised new issue on risk management: cybersecurity. We have to watch closely the progress of safety standard development. PMID:26736611

  4. New Multiphase Matrix Converter Based Device for Power Flow Control

    OpenAIRE

    Jerzy Szczepanik; Tomasz Sieńko

    2013-01-01

    The article presents the concept of new matrix converter (MC) based device working as a phase shifting control device in a power system. The multiphase MC is working under an innovative control algorithm specially dedicated to the proposed application. The work presents the results of the simulation of the MC work in this application as well as the analysis of the MC properties.

  5. Novel Materials for Prosthetic Liners

    Science.gov (United States)

    Ragolta, Carolina I.; Morford, Megan

    2011-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury that reduce quality of life. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications. Three tests were performed on several types of aerogel to assess the properties of each material. Moisture vapor permeability was tested by incubating four aerogel varieties with an artificial sweat solution at 37.0 C and less than 20% relative humidity for 24 hours. Two aerogel varieties were eliminated from the study due to difficulties in handling the material, and further testing proceeded with Pyrogel in 2.0 and 6.0 mm thicknesses. Force distribution was tested by compressing samples under a load of 4448 N at a rate of 2.5 mm/min. Biofilm formation was tested in a high-shear CDC Biofilm Reactor. Results showed that 2.0 mm Pyrogel blanket allowed 55.7 plus or minus 28.7% of an artificial sweat solution to transpire, and 35.5 plus or minus 27.8% transpired through 6.0 mm Pyrogel blanket. Samples also outperformed the load-bearing capabilities of existing liner materials. No statistically significant difference was found between the two Pyrogel thicknesses for either moisture vapor permeability or force distribution. In addition, biofilm formation results showed no change between the two Pyrogel thicknesses. The breathability and load bearing properties of aerogel make it a suitable material for application to prosthetic liners.

  6. Memristive Hebbian plasticity model: device requirements for the emulation of Hebbian plasticity based on memristive devices.

    Science.gov (United States)

    Ziegler, Martin; Riggert, Christoph; Hansen, Mirko; Bartsch, Thorsten; Kohlstedt, Hermann

    2015-04-01

    In this work we present a phenomenological model for synaptic plasticity suitable to describe common plasticity measurements of memristive devices. We show evidence that the presented model is basically compatible with advanced biophysical plasticity models, which account for a large body of experimental data on spike-timing-depending plasticity (STDP) as an asymmetric form of Hebbian learning. The basic characteristics of our model are a saturation of the synaptic weight growth and a weight dependent learning rate. Moreover, it accounts for common resistive switching behaviors of memristive devices under voltage pulse application and allows to study essential requirements of individual memristive devices for the emulation of Hebbian plasticity in neuromorphic circuits. In this respect, memristive devices based on mixed ionic/electronic and one exclusively electronic mechanism are explored. The ionic/electronic devices consist of the layer sequence metal/isolator/metal and represent today's most popular devices. The electronic device is a MemFlash-cell which is based on a conventional floating gate transistor in a diode configuration wiring scheme exhibiting a memristive (pinched) I-V characteristic. PMID:25879966

  7. Electrochemical sensing in paper-based microfluidic devices.

    Science.gov (United States)

    Nie, Zhihong; Nijhuis, Christian A; Gong, Jinlong; Chen, Xin; Kumachev, Alexander; Martinez, Andres W; Narovlyansky, Max; Whitesides, George M

    2010-02-21

    This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, microPEDs). The microPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the microPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucose) in aqueous solutions. This low-cost analytical device should be useful for applications in public health, environmental monitoring, and the developing world. PMID:20126688

  8. Brucella Endocarditis in Prosthetic Valves

    Science.gov (United States)

    Mehanic, Snjezana; Mulabdic, Velida; Baljic, Rusmir; Hadzovic-Cengic, Meliha; Pinjo, Fikret; Hadziosmanovic, Vesna; Topalovic, Jasna

    2012-01-01

    SUMMARY CONFLICT OF INTEREST: none declared. Introduction Brucella endocarditis (BE) is a rare but severe and potentially lethal manifestation of brucellosis. Pre-existing valves lesions and prosthetic valves (PV) are favorable for BE. Case report We represent the case of a 46-year-old man who was treated at the Clinic for Infectious Diseases, Clinical Center of Sarajevo University, as blood culture positive (Brucella melitensis) mitral and aortic PV endocarditis. He was treated with combined anti-brucella and cardiac therapy. Surgical intervention was postponed due to cardiac instability. Four months later he passed away. Surgery was not performed. PMID:24493988

  9. 基于有限状态机控制的智能假肢踝关节*☆%Intelligent prosthetic ankle based on the finite state machine control

    Institute of Scientific and Technical Information of China (English)

    杨鹏; 柏健; 王欣然; 耿艳利

    2013-01-01

    BACKGROUND: At present, intel igent prosthesis only focuses on the function of knee joint, while ankle joint prosthesis is only used as the aid of prosthetic knee joint. So the normal gait cannot be realized according to the change of external environment and gait. OBJECTIVE: To develop a reliable intel igent prosthetic ankle in order to improve the gait of amputees effectively. METHODS: Based on the variable damping ankle-foot prosthesis, the control method of finite state machine was proposed. The ankle joint gait was planned in detail, and the relevant control strategy was developed. RESULTS AND CONCLUSION: Results indicate that the intel igent prosthetic ankle based on the finite state machine control can effectively fol ow health limb lateral movement, and can adapt to different paces, which lays an experimental basement for later knee ankle coordinated movement.%  背景:目前智能假肢只是考虑了膝关节的作用,假肢踝关节只是作为假肢膝关节的辅助工具,无法根据外部环境和步态的变化实现假肢自然的行走。目的:研制出可靠的智能假肢踝关节,有效改善截肢者的步态。方法:在阻尼可变式踝足假肢的基础上,提出了有限状态机的控制方法,对踝足步态进行了详细的划分,在每个步态内制定了相关的控制策略。结果与结论:实验结果表明,基于有限状态机控制的智能假肢踝关节能够有效的跟随健肢侧运动,能够适应不同的步速,为以后膝踝协调运动奠定了一定的实验基础。

  10. Development of EPICS device/driver support modules for network-based devices

    International Nuclear Information System (INIS)

    A set of EPICS device/driver support modules has been developed based on a consolidated design in order to support many different types of network-based devices for the minimal effort of development. The library has been upgraded to make it work with EPICS 3.14, which runs on multiple operating systems including Linux. Cost effective control with the library running on PC/Linux has been adopted in many EPICS-based control systems of new accelerators under development or construction, as well as accelerators currently in operation. (author)

  11. Multiferroic materials for spin-based logic devices

    OpenAIRE

    de Sousa, Rogerio; Moore, Joel E.

    2008-01-01

    Logical devices based on spin waves offer the potential to avoid dissipation mechanisms that limit devices based on either the charge or spin of mobile electrons. Multiferroic magnetoelectrics, which are materials that combine ferroelectric and magnetic order, allow direct switching of magnetic order and thence of spin-wave properties using an applied electric field. The intrinsic coupling between polarization and magnetic moments, generated by strong electronic correlations in these multifer...

  12. Fachtagung 'carbon-nanophysics': carbon based organic optoelectronic devices

    International Nuclear Information System (INIS)

    Full text: Recent developments on carbon based organic light emitting diodes (OLEDs), photovoltaic diodes (OPVs) and photoactive organic field effect transistors (photOFETs) are discussed. The photophysics of such devices is based on the photoinduced charge and/or energy transfer interactions between donor type semiconducting conjugated materials and acceptor type conjugated molecules such as Buckminster-fullerene, C60. Furthermore, organic/inorganic nanoparticle based 'hybrid' devices will be discussed. This talk gives an overview of materials' aspect, charge-transport, and device physics of organic diodes and field-effect transistors. Due to the compatibility of carbon/ hydrogen based organic semiconductors with organic biomolecules and living cells there can be a great opportunity to integrate such organic semiconductor devices (biOFETs) with the living organisms. In general, bio/life sciences and information technology can be bridged in an advanced cybernetic approach using organic semiconductor devices embedded in bio-life sciences. This field of bio-organic electronic devices is proposed to be an important mission of organic semiconductor devices. (author)

  13. A Miniature Force Sensor for Prosthetic Hands

    Science.gov (United States)

    Platt, Robert; Chu, Mars; Diftler, Myron; Martin, Toby; Valvo, Michael

    2006-01-01

    Tactile sensing is an important part of the development of new prosthetic hands. A number of approaches to establishing an afferent pathway back to the patient for tactile information are becoming available including tactors and direct stimulation of the afferent nerves. Tactile information can also be used by low-level control systems that perform simple tasks for the patient such as establishing a stable grasp and maintaining the grasping forces needed to hold an object. This abstract reports on the design of a small fingertip load cell based on semi-conductor strain gauges. Since this load cell is so small (measuring only 8.5mm in diameter and 6.25 mm in height), it easily fits into the tip of an anthropomorphic mechatronic hand. This load cell is tested by comparing a time series of force and moment data with reference data acquired from a much larger high-precision commercial load cell.

  14. A Flexible Microcontroller-Based Data Acquisition Device

    Directory of Open Access Journals (Sweden)

    Darko Hercog

    2014-06-01

    Full Text Available This paper presents a low-cost microcontroller-based data acquisition device. The key component of the presented solution is a configurable microcontroller-based device with an integrated USB transceiver and a 12-bit analogue-to-digital converter (ADC. The presented embedded DAQ device contains a preloaded program (firmware that enables easy acquisition and generation of analogue and digital signals and data transfer between the device and the application running on a PC via USB bus. This device has been developed as a USB human interface device (HID. This USB class is natively supported by most of the operating systems and therefore any installation of additional USB drivers is unnecessary. The input/output peripheral of the presented device is not static but rather flexible, and could be easily configured to customised needs without changing the firmware. When using the developed configuration utility, a majority of chip pins can be configured as analogue input, digital input/output, PWM output or one of the SPI lines. In addition, LabVIEW drivers have been developed for this device. When using the developed drivers, data acquisition and signal processing algorithms as well as graphical user interface (GUI, can easily be developed using a well-known, industry proven, block oriented LabVIEW programming environment.

  15. Prosthetic

    Directory of Open Access Journals (Sweden)

    Pokpong Amornvit

    2014-01-01

    Full Text Available Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results.

  16. Internal Location Based System for Mobile Devices Using Passive RFID

    CERN Document Server

    Vhatkar, Kapil N

    2010-01-01

    We have explored our own innovative work about the design & development of internal location-identification system for mobile devices based on integration of RFID and wireless technology. The function of our system is based on strategically located passive RFID tags placed on objects around building which are identified using an RFID reader attached to a mobile device. The mobile device reads the RFID tag and through the wireless network, sends the request to the server. The server resolves the request and sends the desired location-based information back to the mobile device. We had addressed that we can go through the RFID technology for internal location identification (indoor), which provides us better location accuracy because of no contact between the tag and the reader, and the system requires no line of sight. In this paper we had also focused on the issues of RFID technologies i.e. Non-line-of-sight & High inventory speeds.

  17. Medical Device Integration Model Based on the Internet of Things.

    Science.gov (United States)

    Hao, Aiyu; Wang, Ling

    2015-01-01

    At present, hospitals in our country have basically established the HIS system, which manages registration, treatment, and charge, among many others, of patients. During treatment, patients need to use medical devices repeatedly to acquire all sorts of inspection data. Currently, the output data of the medical devices are often manually input into information system, which is easy to get wrong or easy to cause mismatches between inspection reports and patients. For some small hospitals of which information construction is still relatively weak, the information generated by the devices is still presented in the form of paper reports. When doctors or patients want to have access to the data at a given time again, they can only look at the paper files. Data integration between medical devices has long been a difficult problem for the medical information system, because the data from medical devices are lack of mandatory unified global standards and have outstanding heterogeneity of devices. In order to protect their own interests, manufacturers use special protocols, etc., thus causing medical decices to still be the "lonely island" of hospital information system. Besides, unfocused application of the data will lead to failure to achieve a reasonable distribution of medical resources. With the deepening of IT construction in hospitals, medical information systems will be bound to develop towards mobile applications, intelligent analysis, and interconnection and interworking, on the premise that there is an effective medical device integration (MDI) technology. To this end, this paper presents a MDI model based on the Internet of Things (IoT). Through abstract classification, this model is able to extract the common characteristics of the devices, resolve the heterogeneous differences between them, and employ a unified protocol to integrate data between devices. And by the IoT technology, it realizes interconnection network of devices and conducts associate matching

  18. Fullerene based devices for molecular electronics

    OpenAIRE

    G. Cuniberti; R. GUTIERREZ; Fagas, G.; Grossmann, F.; Richter, K; Schmidt, R.

    2001-01-01

    We have investigated the electronic properties of a C_60 molecule in between carbon nanotube leads. This problem has been tackled within a quantum chemical treatment utilizing a density functional theory-based LCAO approach combined with the Landauer formalism. Owing to low-dimensionality, electron transport is very sensitive to the strength and geometry of interfacial bonds. Molecular contact between interfacial atoms and electrodes gives rise to a complex conductance dependence on the elect...

  19. A rhythm-based authentication scheme for smart media devices.

    Science.gov (United States)

    Lee, Jae Dong; Jeong, Young-Sik; Park, Jong Hyuk

    2014-01-01

    In recent years, ubiquitous computing has been rapidly emerged in our lives and extensive studies have been conducted in a variety of areas related to smart devices, such as tablets, smartphones, smart TVs, smart refrigerators, and smart media devices, as a measure for realizing the ubiquitous computing. In particular, smartphones have significantly evolved from the traditional feature phones. Increasingly higher-end smartphone models that can perform a range of functions are now available. Smart devices have become widely popular since they provide high efficiency and great convenience for not only private daily activities but also business endeavors. Rapid advancements have been achieved in smart device technologies to improve the end users' convenience. Consequently, many people increasingly rely on smart devices to store their valuable and important data. With this increasing dependence, an important aspect that must be addressed is security issues. Leaking of private information or sensitive business data due to loss or theft of smart devices could result in exorbitant damage. To mitigate these security threats, basic embedded locking features are provided in smart devices. However, these locking features are vulnerable. In this paper, an original security-locking scheme using a rhythm-based locking system (RLS) is proposed to overcome the existing security problems of smart devices. RLS is a user-authenticated system that addresses vulnerability issues in the existing locking features and provides secure confidentiality in addition to convenience. PMID:25110743

  20. A Rhythm-Based Authentication Scheme for Smart Media Devices

    Directory of Open Access Journals (Sweden)

    Jae Dong Lee

    2014-01-01

    Full Text Available In recent years, ubiquitous computing has been rapidly emerged in our lives and extensive studies have been conducted in a variety of areas related to smart devices, such as tablets, smartphones, smart TVs, smart refrigerators, and smart media devices, as a measure for realizing the ubiquitous computing. In particular, smartphones have significantly evolved from the traditional feature phones. Increasingly higher-end smartphone models that can perform a range of functions are now available. Smart devices have become widely popular since they provide high efficiency and great convenience for not only private daily activities but also business endeavors. Rapid advancements have been achieved in smart device technologies to improve the end users’ convenience. Consequently, many people increasingly rely on smart devices to store their valuable and important data. With this increasing dependence, an important aspect that must be addressed is security issues. Leaking of private information or sensitive business data due to loss or theft of smart devices could result in exorbitant damage. To mitigate these security threats, basic embedded locking features are provided in smart devices. However, these locking features are vulnerable. In this paper, an original security-locking scheme using a rhythm-based locking system (RLS is proposed to overcome the existing security problems of smart devices. RLS is a user-authenticated system that addresses vulnerability issues in the existing locking features and provides secure confidentiality in addition to convenience.

  1. Integrating Android Devices into Network Management Systems based on SNMP

    Directory of Open Access Journals (Sweden)

    Fernando Hidalgo

    2014-06-01

    Full Text Available Mobile devices are becoming essential for today life. In developed countries, about half of the people have a smartphone, resulting in millions of these electronic devices. Android is the most popular operating system for smartphones and other electronic devices such as tablets. Hence, for network administrators, it is essential to start managing all the Android based devices. SNMP is the de facto standard for network administration, where agents that are running in managed devices are polled by management stations. Some primitive tools have already been developed to transform an Android device as a basic management station. However, so far, there is no SNMP agent for this operating system. In this paper, we develop the first SNMP agent for Android. We also propose an SNMP benchmark to study the SNMP traffic that can be supported by our SNMP agent over some real and actual Android devices. The results obtained show that it is realistic to integrate mobile Android devices in network management systems since they can handle a high number of SNMP requests in a reasonable period of time.

  2. The Role of Virtual Articulator in Prosthetic and Restorative Dentistry

    OpenAIRE

    Koralakunte, Pavankumar Ravi; Aljanakh, Mohammad

    2014-01-01

    Virtual reality is a computer based technology linked with the future of dentistry and dental practice. The virtual articulator is one such application in prosthetic and restorative dentistry based on virtual reality that will significantly reduce the limitations of the mechanical articulator, and by simulation of real patient data, allow analyses with regard to static and dynamic occlusion as well as to jaw relation. It is the purpose of this article to present the concepts and strategies fo...

  3. Secure voice based authentication for mobile devices: Vaulted Voice Verification

    OpenAIRE

    Johnson, R C; Scheirer, Walter J.; Boult, Terrance E.

    2012-01-01

    As the use of biometrics becomes more wide-spread, the privacy concerns that stem from the use of biometrics are becoming more apparent. As the usage of mobile devices grows, so does the desire to implement biometric identification into such devices. A large majority of mobile devices being used are mobile phones. While work is being done to implement different types of biometrics into mobile phones, such as photo based biometrics, voice is a more natural choice. The idea of voice as a biomet...

  4. Magneto-optical switching devices based on Si resonators

    Science.gov (United States)

    Noda, Kazuki; Okada, Kazuya; Amemiya, Yoshiteru; Yokoyama, Shin

    2016-04-01

    The magneto-optical switching devices based on Si ring and Si photonic crystal resonators have been fabricated using a Bi3Fe5O12 (BIG) film deposited by the metal organic decomposition (MOD) method. The quality of the obtained BIG film was evaluated by X-ray diffraction and the magneto-optical Kerr effect and relatively good results were obtained. The light modulations of both devices were ≦20% at a wavelength of ˜1.5 µm. The operation mechanisms of both devices are explained by the Cotton-Mouton effect where the magnetic field direction is perpendicular to the light propagation direction.

  5. Design of magneto-rheological fluid based device

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Hoon; Lee, Chong Won; Jung, Byung Bo; Park, Young Jin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Cao, Guangzhong [Shenzhen Univ., Guangdong (China)

    2001-11-01

    The effect of power supply voltage on the performance limits in a laboratory magneto-rheological fluid based device was identified by experiments. It suggests that the frequency range of motion for control is limited by the voltage attenuation due to the coil inductance and the maximum power supply voltage set for practical use of an MAF devices. In this work, the magnetic and electrical characteristics of the MRF device are investigated and a design procedure is formulated to achieve the desired performance for a given power supply.

  6. Design of magneto-rheological fluid based device

    International Nuclear Information System (INIS)

    The effect of power supply voltage on the performance limits in a laboratory magneto-rheological fluid based device was identified by experiments. It suggests that the frequency range of motion for control is limited by the voltage attenuation due to the coil inductance and the maximum power supply voltage set for practical use of an MAF devices. In this work, the magnetic and electrical characteristics of the MRF device are investigated and a design procedure is formulated to achieve the desired performance for a given power supply

  7. Electrochemical model of the polyaniline based organic memristive device

    Energy Technology Data Exchange (ETDEWEB)

    Demin, V. A., E-mail: demin.vyacheslav@mail.ru, E-mail: victor.erokhin@fis.unipr.it [National Research Centre ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Moscow Institute of Physics and Technology (State University), 141700 Dolgoprudny, Moscow Region (Russian Federation); Erokhin, V. V., E-mail: demin.vyacheslav@mail.ru, E-mail: victor.erokhin@fis.unipr.it [CNR-IMEM (National Research Council, Institute of Materials for Electronics and Magnetism) and University of Parma, Viale Usberti 7A, 42124 Parma (Italy); Kashkarov, P. K.; Kovalchuk, M. V. [National Research Centre ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Moscow Institute of Physics and Technology (State University), 141700 Dolgoprudny, Moscow Region (Russian Federation); Lomonosov Moscow State University, GSP-1, Leninskie Gory, 119991 Moscow (Russian Federation)

    2014-08-14

    The electrochemical organic memristive device with polyaniline active layer is a stand-alone device designed and realized for reproduction of some synapse properties in the innovative electronic circuits, including the neuromorphic networks capable for learning. In this work, a new theoretical model of the polyaniline memristive is presented. The developed model of organic memristive functioning was based on the detailed consideration of possible electrochemical processes occuring in the active zone of this device. Results of the calculation have demonstrated not only the qualitative explanation of the characteristics observed in the experiment but also the quantitative similarities of the resultant current values. It is shown how the memristive could behave at zero potential difference relative to the reference electrode. This improved model can establish a basis for the design and prediction of properties of more complicated circuits and systems (including stochastic ones) based on the organic memristive devices.

  8. Assistive Technology Based on Robotics and Rise in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaoyu; WANG Kaixuan

    2013-01-01

    The concept of assistive technology based on robotics,rehabilitation robot and intelligent assistive devices.Domestic intelligence assistive devices include intelligent prosthetics,intelligent orthotics,intelligent walker,assistive devices for smart home environment control,intelligent life assistive devices; Domestic intelligent rehabilitation robot include upper limb rehabilitation robot,hand rehabilitation robot,lower limb rehabilitation robot,robotic smart wheelchair,intelligent nursing bed,daily care robot,the development trend of intelligent assistive devices and rehabilitation robot.

  9. Carbon Nanotube Based Spike Neuromorphic Devices and Circuits

    OpenAIRE

    Shen, Alex

    2014-01-01

    Fabrication and operation of carbon nanotube (CNT) based electronic devices called "synapstors," with the goal of emulating the functions of biological synapses, are reported. These synapstors have a structure akin to field-effect transistors, utilizing a random network of single-wall semiconducting CNTs as its conducting channel. Analog spike signal processing with low power consumption was demonstrated. These synaptic devices are capable of carrying out logic, learning, and memory functions...

  10. WAVELET-BASED WARPING TECHNIQUE FOR MOBILE DEVICES

    OpenAIRE

    Ekta Walia; Vishal Verma,

    2014-01-01

    The role of digital images is increasing rapidly in mobile devices. They are used in many applications including virtual tours, virtual reality, e-commerce etc. Such applications synthesize realistic looking novel views of the reference images on mobile devices using the techniques like image-based rendering (IBR). However, with this increasing role of digital images comes the serious issue of processing large images which requires considerable time. Hence, methods to compress ...

  11. New Multiphase Matrix Converter Based Device for Power Flow Control

    Directory of Open Access Journals (Sweden)

    Jerzy Szczepanik

    2013-12-01

    Full Text Available The article presents the concept of new matrix converter (MC based device working as a phase shifting control device in a power system. The multiphase MC is working under an innovative control algorithm specially dedicated to the proposed application. The work presents the results of the simulation of the MC work in this application as well as the analysis of the MC properties.

  12. Optimal design of phosphorylation-based insulation devices

    OpenAIRE

    Rivera, Phillip M.; Del Vecchio, Domitilla

    2013-01-01

    We seek to minimize both the retroactivity to the output and the retroactivity to the input of a phosphorylation-based insulation device by finding an optimal substrate concentration. Characterizing and improving the performance of insulation devices brings us a step closer to their successful implementation in biological circuits, and thus to modularity. Previous works have mainly focused on attenuating retroactivity effects to the output using high substrate concentrations. This, however, w...

  13. Prosthetic rehabilitation of the upper limb amputee

    Directory of Open Access Journals (Sweden)

    Bernard O′Keeffe

    2011-01-01

    Full Text Available The loss of all or part of the arm is a catastrophic event for a patient and a significant challenge to rehabilitation professionals and prosthetic engineers. The large, upper extremity amputee population in India has, historically, been poorly served, with most having no access to support or being provided with ineffective prostheses. In recent years, the arrival of organisations like Otto Bock has made high quality service standards and devices accessible to more amputees. This review attempts to provide surgeons and other medical professionals with an overview of the multidisciplinary, multistage rehabilitation process and the solution options available. With worldwide upper extremity prosthesis rejection rates at significant levels, the review also describes some of the factors which influence the outcome. This is particularly relevant in the Indian context where the service can involve high cost investments. It is the responsibility of all contributing professionals to guide vulnerable patients through the process and try to maximise the benefit that can be obtained within the resources available.

  14. Electrochemical Sensing in Paper-Based Microfluidic Devices

    OpenAIRE

    Nie, Zhihong; Nijhuis, Christian A.; Gong, Jinlong; Chen, Xin; Kumachev, Alexander; Martinez, Andres W.; Narovlyansky, Max; Whitesides, George McClelland

    2010-01-01

    This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, μPEDs). The μPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the μPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucos...

  15. Development of prosthetic arm with pneumatic prosthetic hand and tendon-driven wrist.

    Science.gov (United States)

    Takeda, Hiroyuki; Tsujiuchi, Nobutaka; Koizumi, Takayuki; Kan, Hiroto; Hirano, Masanori; Nakamura, Yoichiro

    2009-01-01

    Recently, various prosthetic arms have been developed, but few are both attractive and functional. Considering human coexistence, prosthetic arms must be both safe and flexible. In this research, we developed a novel prosthetic arm with a five-fingered prosthetic hand using our original pneumatic actuators and a slender tendon-driven wrist using a wire drive and two small motors. Because the prosthetic hand's driving source is comprised of small pneumatic actuators, the prosthetic hand is safe when it makes contact with people; it can also operate flexibly. In addition, the arm has a tendon-driven wrist to expand its motion space and to perform many operations. First, we explain the pneumatic hand's drive mechanism and its tendon-driven wrist. Next, we identify the characteristics of the hand and the wrist and construct a control system for this arm and verify its control performance. PMID:19964378

  16. Effects of a flat prosthetic foot rocker section on balance and mobility

    OpenAIRE

    Andrew Hansen, PhD; Eric Nickel, MS; Joseph Medvec, CP; Steven Brielmaier, DPT; Alvin Pike, CP; Marilyn Weber, MD

    2014-01-01

    Previous studies have shown that the effective rocker shape of the physiologic ankle-foot system during standing and fore-aft swaying is much flatter than that used during walking, which indicates a more stable base of support for the standing/swaying activity. Previous work suggests that flat regions within the effective rocker shapes of prosthetic ankle-foot systems could provide enhanced stability for standing balance tasks. An experimental prosthetic foot was altered to provide three diff...

  17. MOF-based electronic and opto-electronic devices.

    Science.gov (United States)

    Stavila, V; Talin, A A; Allendorf, M D

    2014-08-21

    Metal-organic frameworks (MOFs) are a class of hybrid materials with unique optical and electronic properties arising from rational self-assembly of the organic linkers and metal ions/clusters, yielding myriads of possible structural motifs. The combination of order and chemical tunability, coupled with good environmental stability of MOFs, are prompting many research groups to explore the possibility of incorporating these materials as active components in devices such as solar cells, photodetectors, radiation detectors, and chemical sensors. Although this field is only in its incipiency, many new fundamental insights relevant to integrating MOFs with such devices have already been gained. In this review, we focus our attention on the basic requirements and structural elements needed to fabricate MOF-based devices and summarize the current state of MOF research in the area of electronic, opto-electronic and sensor devices. We summarize various approaches to designing active MOFs, creation of hybrid material systems combining MOFs with other materials, and assembly and integration of MOFs with device hardware. Critical directions of future research are identified, with emphasis on achieving the desired MOF functionality in a device and establishing the structure-property relationships to identify and rationalize the factors that impact device performance. PMID:24802763

  18. Maxillofacial prosthetic rehalibilation of the oral cancer patient

    International Nuclear Information System (INIS)

    The victim of orofacial cancer is frequently subjected to severe morphological and functional disturbance: a condition which the maxillofacial prosthetist can do much to alleviate through the use of various prosthetic devices. The successful rehabilitation of these patients, however, is often compromised by the presence of psychosocial and other problems, the solution of which extends beyond the limits of a single clinical discipline. The modern approach to orofacial cancer, therefore, is organised within the context of interdisciplinary co-operation: each phase of patient management being planed and executed according to the co-ordinated efforts of the various members of a head and neck cancer team

  19. Development and marketing of a prosthetic urinary control valve system

    Science.gov (United States)

    Tenney, J. B., Jr.; Rabinowitz, R.; Rogers, D. W.; Harrison, H. N.

    1983-01-01

    An implantable prosthetic for the control of urinary incontinence was developed and marketed. Three phases are presented: bench development studies, animal trials, and human clinical trials. This work was performed under the direction of a Research Team at Rochester General Hospital (RGH). Bench trials were completed on prototype hardware and provided early verification of the device's ability to withstand repeated cyclic testing. Configurational variants were evaluated and a preferred design concept was established. Silicone rubber (medical grade) was selected as the preferred material for the prosthesis.

  20. A planar parallel manipulator based novel MEMS device bonding system

    Institute of Scientific and Technical Information of China (English)

    Ji Junhong; Sun Lining; Zhu Yuhong

    2006-01-01

    A novel MEMS device boning system is presented. Aiming at the high velocity, high precision and high flexibility requirements, a novel manipulator of planar parallel structure is developed to substitute ordinary X-Y table. In addition, the machine vision is implemented to improve the system's flexibility. The initial angular positions of the joints are estimated by the extended Kalman filter algorithm. As a result, the manipulator's absolute locating accuracy in its workspace is guaranteed indirectly. For any MEMS device, the bonding system itself can be used as measurement equipment to create the device's geometry model, which is the base to do off-line programming. A quite ideal trade-off between the system's flexibility and efficiency is got. Finally, some verified motion specification of the manipulator, the bonding experimental results and the verified qualities of the bonded devices are provided.

  1. Design and development of a prosthetic implant for cardiovascular reconstructions

    OpenAIRE

    Ahmed, M.

    2011-01-01

    There is a significant worldwide demand for a small calibre vascular graft for use as a bypass or replacement conduit. Our lab has developed a novel nanocomposite poly- mer based on polyhedral oligomeric silsesquioxane and poly(carbonate-urea)urethane (POSS-PCU) which has displayed promising properties in vitro. In this thesis, POSS- PCU has been utilised to fabricate prosthetic small calibre conduits for use as arterial replacements. An important feature in determining the succes...

  2. Subjective assessment of mastication as parameter for successful prosthetic therapy

    OpenAIRE

    Milekić Bojana; Puškar Tatjana; Marković Dubravka

    2009-01-01

    Introduction. Success in functional rehabilitation of the craniomandibular system in patients without teeth, which have total prosthesis, can be assessed using different clinical and functional methods. Subjective assessment, motivation, comfort level and functional efficacy are important elements for adaptation to dental prosthesis as well as base for success in prosthetic therapy. The aim of this study was to evaluate the importance of subjective assessment of the mastication in people with...

  3. DME Prosthetics Orthotics, and Supplies Fee Schedule

    Data.gov (United States)

    U.S. Department of Health & Human Services — Durable Medical Equipment, Prosthetics-Orthotics, and Supplies Fee Schedule. The list contains the fee schedule amounts, floors, and ceilings for all procedure...

  4. Modeling and characterization of MEMS-based piezoelectric harvesting devices

    International Nuclear Information System (INIS)

    Vibrational piezoelectric harvesting devices (PHD) provide an autonomous power source for various types of sensors, actuators and MEMS devices. There have been several examples of vibrational energy harvesters published in the literature over the years. However, for many applications the generated power is not yet sufficient. In this paper, a physical model for predicting the generated electric power from piezoelectric harvesting devices is introduced. The model is based on estimating the total charge generated on a piezoelectric material when it is subjected to mechanical strain as a result of bending at the fundamental resonance frequency. Based on Euler–Bernoulli beam theory, the strain can be determined in terms of the beam deflection at purely mechanical excitation. The proposed model extends the current state of the art by consideration of the strain distribution due to the presence of an extended mass volume at the end of the beam. The constitutive equations of piezoelectricity in the sensing mode correlate the strain and the induced charge in the piezoelectric element. Using the device design parameters and the beam deflection as inputs, the power output can be calculated. The results of the model were experimentally verified for MEMS-based PHDs. The model was found to give an accurate prediction of the electrical parameters under various damping conditions. After model validation, a subsequent device optimization has been made to improve the power generation

  5. {100}<100> or 45.degree.-rotated {100}<100>, semiconductor-based, large-area, flexible, electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Amit (Knoxville, TN)

    2012-05-15

    Novel articles and methods to fabricate the same resulting in flexible, {100}<100> or 45.degree.-rotated {100}<100> oriented, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  6. A point acoustic device based on aluminum nanowires

    Science.gov (United States)

    Xie, Qian-Yi; Ju, Zhen-Yi; Tian, He; Xue, Qing-Tang; Chen, Yuan-Quan; Tao, Lu-Qi; Mohammad, Mohammad Ali; Zhang, Xue-Yue; Yang, Yi; Ren, Tian-Ling

    2016-03-01

    A point Electrical Thermal Acoustic (ETA) device based on aluminum nanowire contacts is designed and fabricated. Interdigitated structural aluminum nanowires are released from the substrate by Inductively Coupled Plasma Reactive Ion Etching (ICP-RIE). By releasing the interdigitated structure, the nanowires contact each other at approximately 1 mm above the wafer, forming a Point Contact Structure (PCS). It is found that the PCS acoustic device realizes high efficiency when a biased AC signal is applied. The PCS acoustic device reaches a sound pressure level as high as 67 dB at a distance of 1 cm with 74 mW AC input. The power spectrum is flat, ranging from 2 kHz to 20 kHz with a less than +/-3 dB fluctuation. The highest normalized Sound Pressure Level (SPL) of the point contact structure acoustic device is 18 dB higher than the suspended aluminum wire acoustic device. Comparisons between the PCS acoustic device and the Suspended Aluminum Nanowire (SAN) acoustic device illustrate that the PCS acoustic device has a flatter power spectrum within the 20 kHz range, and enhances the SPL at a lower frequency. Enhancing the response at lower frequencies is extremely useful, which may enable earphone and loudspeaker applications within the frequency range of the human ear with the help of pulse density modulation.A point Electrical Thermal Acoustic (ETA) device based on aluminum nanowire contacts is designed and fabricated. Interdigitated structural aluminum nanowires are released from the substrate by Inductively Coupled Plasma Reactive Ion Etching (ICP-RIE). By releasing the interdigitated structure, the nanowires contact each other at approximately 1 mm above the wafer, forming a Point Contact Structure (PCS). It is found that the PCS acoustic device realizes high efficiency when a biased AC signal is applied. The PCS acoustic device reaches a sound pressure level as high as 67 dB at a distance of 1 cm with 74 mW AC input. The power spectrum is flat, ranging from 2 k

  7. Electrochromic Devices Based on Porous Tungsten Oxide Thin Films

    Directory of Open Access Journals (Sweden)

    Y. Djaoued

    2012-01-01

    Full Text Available Recent developments in the synthesis of transition metal oxides in the form of porous thin films have opened up opportunities in the construction of electrochromic devices with enhanced properties. In this paper, synthesis, characterization and electrochromic applications of porous WO3 thin films with different nanocrystalline phases, such as hexagonal, monoclinic, and orthorhombic, are presented. Asymmetric electrochromic devices have been constructed based on these porous WO3 thin films. XRD measurements of the intercalation/deintercalation of Li+ into/from the WO3 layer of the device as a function of applied coloration/bleaching voltages show systematic changes in the lattice parameters associated with structural phase transitions in LixWO3. Micro-Raman studies show systematic crystalline phase changes in the spectra of WO3 layers during Li+ ion intercalation and deintercalation, which agree with the XRD data. These devices exhibit interesting optical modulation (up to ~70% due to intercalation/deintercalation of Li ions into/from the WO3 layer of the devices as a function of applied coloration/bleaching voltages. The obtained optical modulation of the electrochromic devices indicates that, they are suitable for applications in electrochromic smart windows.

  8. WAVELET-BASED WARPING TECHNIQUE FOR MOBILE DEVICES

    Directory of Open Access Journals (Sweden)

    Ekta Walia

    2014-07-01

    Full Text Available The role of digital images is increasing rapidly in mobile devices. They are used in many applications including virtual tours, virtual reality, e-commerce etc. Such applications synthesize realistic looking novel views of the reference images on mobile devices using the techniques like image-based rendering (IBR. However, with this increasing role of digital images comes the serious issue of processing large images which requires considerable time. Hence, methods to compress these large images are very important. Wavelets are excellent data compression tools that can be used with IBR algorithms to generate the novel views of compressed image data. This paper proposes a framework that uses wavelet-based warping technique to render novel views of compressed images on mobile/ handheld devices. The experiments are performed using Android Development Tools (ADT which shows the proposed framework gives better results for large images in terms of rendering time.

  9. Implementation of neural networks using quantum well based excitonic devices

    International Nuclear Information System (INIS)

    Implementation is a key bottleneck for tapping the vast potential of neural networks. In this paper the authors examine experimentally and theoretically two devices based on III-V technology, which are critical in the implementation of the Hopfield model as well as other neural type networks for associative memories. The devices are based on Stark effect of excitonic transitions. P-1 (multiquantum wells)-n structures using GaAs/AlGaAs provide a controller-modulator device which has integrating-thresholding properties required of neurons. The p-i-n structures also provide programmable modulators which can serve as a synaptic mask. Using Monte Carlo techniques they examine an all-optical architecture to implement the Hopfield network. No external feedback-thresholding circuitry is required in this implementation due to special design of the controller-modulator device. Speed and stability issues of this architecture are also addressed. The computer simulation results provide valuable insight into how the controller-modulator device should be improved for better network implementation. It is also important to note that the basic technology now exists for such an implementation

  10. Device-independent bit commitment based on the CHSH inequality

    Science.gov (United States)

    Aharon, N.; Massar, S.; Pironio, S.; Silman, J.

    2016-02-01

    Bit commitment and coin flipping occupy a unique place in the device-independent landscape, as the only device-independent protocols thus far suggested for these tasks are reliant on tripartite GHZ correlations. Indeed, we know of no other bipartite tasks, which admit a device-independent formulation, but which are not known to be implementable using only bipartite nonlocality. Another interesting feature of these protocols is that the pseudo-telepathic nature of GHZ correlations—in contrast to the generally statistical character of nonlocal correlations, such as those arising in the violation of the CHSH inequality—is essential to their formulation and analysis. In this work, we present a device-independent bit commitment protocol based on CHSH testing, which achieves the same security as the optimal GHZ-based protocol, albeit at the price of fixing the time at which Alice reveals her commitment. The protocol is analyzed in the most general settings, where the devices are used repeatedly and may have long-term quantum memory. We also recast the protocol in a post-quantum setting where both honest and dishonest parties are restricted only by the impossibility of signaling, and find that overall the supra-quantum structure allows for greater security.

  11. Game theory-based mode cooperative selection mechanism for device-to-device visible light communication

    Science.gov (United States)

    Liu, Yuxin; Huang, Zhitong; Li, Wei; Ji, Yuefeng

    2016-03-01

    Various patterns of device-to-device (D2D) communication, from Bluetooth to Wi-Fi Direct, are emerging due to the increasing requirements of information sharing between mobile terminals. This paper presents an innovative pattern named device-to-device visible light communication (D2D-VLC) to alleviate the growing traffic problem. However, the occlusion problem is a difficulty in D2D-VLC. This paper proposes a game theory-based solution in which the best-response dynamics and best-response strategies are used to realize a mode-cooperative selection mechanism. This mechanism uses system capacity as the utility function to optimize system performance and selects the optimal communication mode for each active user from three candidate modes. Moreover, the simulation and experimental results show that the mechanism can attain a significant improvement in terms of effectiveness and energy saving compared with the cases where the users communicate via only the fixed transceivers (light-emitting diode and photo diode) or via only D2D.

  12. A miniaturized silicon based device for nucleic acids electrochemical detection

    Directory of Open Access Journals (Sweden)

    Salvatore Petralia

    2015-12-01

    The system and the method here reported offer better advantages in term of analytical performances compared to the standard commercial optical-based real-time PCR systems, with the additional incomes of being potentially cheaper and easier to integrate in a miniaturized device.

  13. Dynamical Properties of QD-based Nanolaser Devices

    DEFF Research Database (Denmark)

    Lorke, Michael; Nielsen, Torben Roland; Mørk, Jesper

    2011-01-01

    We investigate the switch-on behavior of semiconductor QD-based nanocavity laser devices. From a microscopic treatment of the carrier-carrier and carrier-photon interaction, we find a fast switch-on, that is accompanied by heavily damped relaxation oscillations and caused by an ultrafast carrier...... dynamics....

  14. Pattern recognition with TiOx-based memristive devices

    Directory of Open Access Journals (Sweden)

    Finn Zahari

    2015-07-01

    Full Text Available We report on the development of TiOx-based memristive devices for bio-inspired neuromorphic systems. In particular, capacitor like structures of Al/AlOx/TiOx/Al with, respectively 20 nm and 50 nm thick TiOx-layers were fabricated and analyzed in terms of their use in neural network circuits. Therefore, an equivalent circuit model is presented which mimics the observed device properties on a qualitative level and relies on mobile oxygen ions by taking electronic transport through local conducting filaments and hopping between TiOx defect states into account. The model also comprises back diffusion of oxygen ions and allows for a realistic description of the experimental recorded device characteristics. The in Refs. [1-3] reported computing paradigms for pattern recognition have been used as guidelines for a device performance investigation at the network level. In particular, simulations of a spiking neural network are presented which allows for pattern recognition. As input patterns hand written digits taken from the MNIST Data base have been used. Within the network the memristive devices are arranged in a cross-bar array connected by 196 input neurons and ten output neurons. While, each input neuron corresponds to a specific pixel of the image of the input pattern, the output neurons were implemented as spiking neurons. In addition, the output neurons were inhibitory linked within an winner-take-it-all network and consist of a homeostasis-like behavior for their spiking thresholds. Based on the network simulation essential requirements for the development of optimal memristive device for neuromorphic circuits are discussed.

  15. Field-Based Experiential Learning Using Mobile Devices

    Science.gov (United States)

    Hilley, G. E.

    2015-12-01

    Technologies such as GPS and cellular triangulation allow location-specific content to be delivered by mobile devices, but no mechanism currently exists to associate content shared between locations in a way that guarantees the delivery of coherent and non-redundant information at every location. Thus, experiential learning via mobile devices must currently take place along a predefined path, as in the case of a self-guided tour. I developed a mobile-device-based system that allows a person to move through a space along a path of their choosing, while receiving information in a way that guarantees delivery of appropriate background and location-specific information without producing redundancy of content between locations. This is accomplished by coupling content to knowledge-concept tags that are noted as fulfilled when users take prescribed actions. Similarly, the presentation of the content is related to the fulfillment of these knowledge-concept tags through logic statements that control the presentation. Content delivery is triggered by mobile-device geolocation including GPS/cellular navigation, and sensing of low-power Bluetooth proximity beacons. Together, these features implement a process that guarantees a coherent, non-redundant educational experience throughout a space, regardless of a learner's chosen path. The app that runs on the mobile device works in tandem with a server-side database and file-serving system that can be configured through a web-based GUI, and so content creators can easily populate and configure content with the system. Once the database has been updated, the new content is immediately available to the mobile devices when they arrive at the location at which content is required. Such a system serves as a platform for the development of field-based geoscience educational experiences, in which students can organically learn about core concepts at particular locations while individually exploring a space.

  16. Analysis of maxillofacial prosthetics at university dental hospitals in the capital region of Korea

    Science.gov (United States)

    Lee, Jong-Ho

    2016-01-01

    PURPOSE The purpose of this study was to investigate the demographic patterns of maxillofacial prosthetic treatment to identify the characteristics and geographic distribution of patients with maxillofacial prosthetics in the capital region of Korea. MATERIALS AND METHODS This retrospective analytical multicenter study was performed by chart reviews. This study included patients who visited the department of prosthodontics at four university dental hospitals for maxillofacial prosthetic rehabilitation. Patients with facial and congenital defects or with insufficient medical data were excluded. The patients were classified into three categories based on the location of the defect. Patients' sex, age, and residential area were analyzed. Pearson's chi-square test with a significance level of 0.05 was used to analyze the variables. RESULTS Among 540 patients with maxillofacial prosthetics, there were 284 (52.59%) male patients and 256 (47.41%) female patients. The number of the patients varied greatly by hospital. Most patients were older than 70, and the most common defect was a hard palate defect. Chi-square analysis did not identify any significant differences in sex, age, and distance to hospital for any defect group (P>.05). CONCLUSION The results of this study indicated that there was imbalance in the distribution of patients with maxillofacial prosthetic among the hospitals in the capital region of Korea. Considerations on specialists and insurance policies for the improvement of maxillofacial prosthetics in Korea are required. PMID:27350859

  17. Effects of a flat prosthetic foot rocker section on balance and mobility

    Directory of Open Access Journals (Sweden)

    Andrew Hansen, PhD

    2014-03-01

    Full Text Available Previous studies have shown that the effective rocker shape of the physiologic ankle-foot system during standing and fore-aft swaying is much flatter than that used during walking, which indicates a more stable base of support for the standing/swaying activity. Previous work suggests that flat regions within the effective rocker shapes of prosthetic ankle-foot systems could provide enhanced stability for standing balance tasks. An experimental prosthetic foot was altered to provide three different flat region lengths within its effective rocker shape. It was hypothesized that longer flat regions of the effective rocker shape would lead to improved standing balance outcomes and reduced walking performance for unilateral transtibial prosthesis users. However, no significant changes were seen in the balance and mobility outcomes of 12 unilateral transtibial prosthesis users when using the three prosthetic foot conditions. Subjects in the study significantly preferred prosthetic feet with relatively low to moderate flat regions over those with long flat regions. All the subjects without loss of light touch or vibratory sensation selected the prosthetic foot with the shortest flat region. More work is needed to investigate the effects of prosthetic foot properties on balance and mobility of prosthesis users.

  18. Electromechanically reconfigurable CdS nanoplate based nonlinear optical device.

    Science.gov (United States)

    Yi, Fei; Ren, Mingliang; Zhu, Hai; Liu, Wenjin; Agarwal, Ritesh; Cubukcu, Ertugrul

    2016-06-13

    Here, we report experimental demonstration of dynamic control and enhancement of second harmonic generation and two photon excited photoluminescence in CdS nanoplates via an electromechanically reconfigurable Fabry-Perot (FP) microcavity. Microcavity coupled CdS nanoplates can be configured as a single or dual wavelength nonlinear light source by tuning the pump wavelength while the output intensities can be tuned by the on-chip control voltage. Our work realizes a reconfigurable device platform with insight toward advanced optical devices based on semiconductor nanoplates for next generation on-chip tunable light sources, sensors and optomechanical systems. PMID:27410362

  19. Electrocaloric devices based on thini-film heat switches

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, Richard I [Los Alamos National Laboratory; Malloy, Kevin J [UNM

    2009-01-01

    We describe a new approach to refrigeration and electrical generation that exploits the attractive properties of thin films of electrocaloric materials. Layers of electrocaloric material coupled with thin-film heat switches can work as either refrigerators or electrical generators, depending on the phasing of the applied voltages and heat switching. With heat switches based on thin layers of liquid crystals, the efficiency of these thin-film heat engines can be at least as high as that of current thermoelectric devices. Advanced heat switches would enable thin-film heat engines to outperform conventional vaporcompression devices.

  20. Nb-based Josephson devices for nuclear detection

    International Nuclear Information System (INIS)

    In this paper experimental results for very high quality Nb based STJs, irradiated by a 55Fe X-Ray source at T=1.5-1.6 K are reported. The fabrication process and a characterization of the junctions behaviour in terms of current-voltage (I-V) characteristics for different temperatures are presented. A device based on long Josephson junction (LJJ) is also proposed as a fast time detector. (orig.)

  1. Cell-Based Biosensors: Electrical Sensing in Microfluidic Devices

    OpenAIRE

    Noemi Rozlosnik; Katrine Kiilerich-Pedersen

    2012-01-01

    Cell-based biosensors provide new horizons for medical diagnostics by adopting complex recognition elements such as mammalian cells in microfluidic devices that are simple, cost efficient and disposable. This combination renders possible a new range of applications in the fields of diagnostics and personalized medicine. The review looks at the most recent developments in cell-based biosensing microfluidic systems with electrical and electrochemical transduction, and relevance to medical diagn...

  2. FEM Analysis of Mandibular Prosthetic Overdenture Supported by Dental Implants: Evaluation of Different Retention Methods

    Science.gov (United States)

    Cicciù, M.; Cervino, G.; Bramanti, E.; Lauritano, F.; Lo Gudice, G.; Scappaticci, L.; Rapparini, A.; Guglielmino, E.; Risitano, G.

    2015-01-01

    Prosthetic rehabilitation of total edentulous jaws patients is today a common technique that clinicians approach in their daily practice. The use of dental implants for replacing missing teeth is going to be a safe technique and the implant-prosthetic materials give the possibility of having long-term clinical success. Aim of this work is to evaluate the mechanical features of three different prosthetic retention systems. By applying engineering systems of investigations like FEM and von Mises analyses, how the dental implant material holds out against the masticatory strength during the chewing cycles has been investigated. Three common dental implant overdenture retention systems have been investigated. The ball attachment system, the locator system, and the common dental abutment have been processed by Ansys Workbench 15.0 and underwent FEM and von Mises investigations. The elastic features of the materials used in the study have been taken from recent literature data. Results revealed different response for both types of device, although locator system showed better results for all conditions of loading. The data of this virtual model show all the features of different prosthetic retention systems under the masticatory load. Clinicians should find the better prosthetic solution related to the patients clinical condition in order to obtain long-term results. PMID:26798405

  3. Graduates’ perceptions of prosthetic and orthotic education and clinical practice in Tanzania and Malawi

    Directory of Open Access Journals (Sweden)

    Lina Magnusson

    2016-02-01

    Full Text Available Background: Maintaining and improving the quality of prosthetics and orthotics education at the Tanzania Training Centre for Orthopaedic Technologists is essential for the provision of appropriate prosthetics and orthotics services in African countries.Objectives: To describe how Tanzanian and Malawian graduates’ of the Diploma in Orthopaedic Technology perceive their education and how it could be improved or supplemented to facilitate clinical practice of graduates.Methods: Nineteen graduates from the diploma course in orthopaedic technology were interviewed and phenomenographic analysis was applied to the data.Results: Seven descriptive categories emerged, namely varied awareness of the profession before starting education, well-equipped teaching facilities, aspects lacking in the learning context, need for changes in the curriculum, enabling people to walk is motivating, obstacles in working conditions and the need for continuous professional development. All participants perceived possible improvements to the content and learning environment.Conclusions: Prosthetic and orthotic education can be better provided by modifying the content of the diploma programme by dedicating more time to the clinical management of different patient groups and applied biomechanics as well as reducing the programme content focusing on technical aspects of prosthetic and orthotic practice. Graduates were not prepared for the rural working conditions and the graduates desired continued training.Keywords: orthotic; prosthetic; education; Malawi; Tanzania; assistive device; assistive technology; developing countries; low-income country

  4. A triple quantum dot based nano-electromechanical memory device

    Energy Technology Data Exchange (ETDEWEB)

    Pozner, R.; Lifshitz, E. [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Solid State Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Peskin, U., E-mail: uri@tx.technion.ac.il [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Lise Meitner Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

    2015-09-14

    Colloidal quantum dots (CQDs) are free-standing nano-structures with chemically tunable electronic properties. This tunability offers intriguing possibilities for nano-electromechanical devices. In this work, we consider a nano-electromechanical nonvolatile memory (NVM) device incorporating a triple quantum dot (TQD) cluster. The device operation is based on a bias induced motion of a floating quantum dot (FQD) located between two bound quantum dots (BQDs). The mechanical motion is used for switching between two stable states, “ON” and “OFF” states, where ligand-mediated effective interdot forces between the BQDs and the FQD serve to hold the FQD in each stable position under zero bias. Considering realistic microscopic parameters, our quantum-classical theoretical treatment of the TQD reveals the characteristics of the NVM.

  5. Development of a flat membrane based device for electromembrane extraction

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Eibak, Lars Erik Eng; Gjelstad, Astrid;

    2014-01-01

    obtaining exhaustive extraction. 2-Nitrophenyl octyl ether was selected as the optimal organic solvent for the supported liquid membrane. From spiked acidified water samples (600μl), EME was carried out with 600μl of 20mM HCOOH as acceptor solution for 15min and with an extraction voltage of 250V. Under......In this work, a single-well electromembrane extraction (EME) device was developed based on a thin (100μm) and flat porous membrane of polypropylene supporting a liquid membrane. The new EME device was operated with a relatively large acceptor solution volume to promote a high recovery. Using this...... EME device, exhaustive extraction of the basic drugs quetiapine, citalopram, amitriptyline, methadone and sertraline was investigated from both acidified water samples and human plasma. The volume of acceptor solution, extraction time, and extraction voltage were found to be important factors for...

  6. New memory devices based on the proton transfer process

    Science.gov (United States)

    Wierzbowska, Małgorzata

    2016-01-01

    Memory devices operating due to the fast proton transfer (PT) process are proposed by the means of first-principles calculations. Writing information is performed using the electrostatic potential of scanning tunneling microscopy (STM). Reading information is based on the effect of the local magnetization induced at the zigzag graphene nanoribbon (Z-GNR) edge—saturated with oxygen or the hydroxy group—and can be realized with the use of giant magnetoresistance (GMR), a magnetic tunnel junction or spin-transfer torque devices. The energetic barriers for the hop forward and backward processes can be tuned by the distance and potential of the STM tip; this thus enables us to tailor the non-volatile logic states. The proposed system enables very dense packing of the logic cells and could be used in random access and flash memory devices.

  7. A triple quantum dot based nano-electromechanical memory device

    International Nuclear Information System (INIS)

    Colloidal quantum dots (CQDs) are free-standing nano-structures with chemically tunable electronic properties. This tunability offers intriguing possibilities for nano-electromechanical devices. In this work, we consider a nano-electromechanical nonvolatile memory (NVM) device incorporating a triple quantum dot (TQD) cluster. The device operation is based on a bias induced motion of a floating quantum dot (FQD) located between two bound quantum dots (BQDs). The mechanical motion is used for switching between two stable states, “ON” and “OFF” states, where ligand-mediated effective interdot forces between the BQDs and the FQD serve to hold the FQD in each stable position under zero bias. Considering realistic microscopic parameters, our quantum-classical theoretical treatment of the TQD reveals the characteristics of the NVM

  8. Gas sensors based on silicon devices with a porous layer

    Science.gov (United States)

    Barillaro, G.; Diligenti, A.; Nannini, A.; Strambini, L. M.

    2005-06-01

    In this work two silicon devices, that is a FET and a p crystalline silicon resistor having porous silicon as adsorbing layer are presented as gas sensors. Owing to they are easily integrable with silicon electronics, these devices could represent an improvement of the functionality of silicon for sensor applications. Unlike other porous silicon-based sensors, in this case the sensing variable is a current flowing in the crystalline silicon, so that the porous silicon film has only the function of adsorbing layer and its properties, electrical or optical, are not directly involved in the measurement. The fabrication processes and an electrical characterization in presence of isopropanol vapors are presented and discussed for both devices.

  9. Nanowire-based resistive switching memories: devices, operation and scaling

    International Nuclear Information System (INIS)

    Nanowires (NWs) represent a logical pathway to extreme scaling of semiconductor devices in the single-digit nanometer scale. Combined with the inherent scalability of the resistive switching memory (RRAM), where the switching region consists of a conductive filament as small as a single atom, NWs may provide an ideal approach to reduce the device area to a range not accessible to conventional lithography. This work reviews NW-based RRAM (NWRRAM) devices. The different approaches to NWRRAMs, including (i) switching in a single metal–oxide NW, (ii) switching in a heterostructured NW with a metal–oxide segment sandwiched between NW metallic electrodes and (iii) switching in a core–shell NW, are discussed. The latter approach is then presented in detail, covering the assembly issues, the robust switching and reliability characteristics, and the scaling outlook. (paper)

  10. Nanotechnology based devices and applications in medicine: An overview

    Directory of Open Access Journals (Sweden)

    Elvis A Martis

    2012-01-01

    Full Text Available Nanotechnology has been the most explored and extensively studied area in recent times. Many devices which were earlier impossible to imagine, are being developed at a lightning speed with the application of nanotechnology. To overcome the challenges offered by the most dreaded diseases, such as cancer or any disease involving the central nervous system or other inaccessible areas of the human body, nanotechnology has been proved to be a boon in making the treatment more target specific and minimizing the toxicities. This review describes a handful of important devices and applications based on nanotechnology in medicine made in recent times. This article also describes in brief the regulatory concerns and the ethical issues pertaining to nanomedical devices.

  11. New memory devices based on the proton transfer process.

    Science.gov (United States)

    Wierzbowska, Małgorzata

    2016-01-01

    Memory devices operating due to the fast proton transfer (PT) process are proposed by the means of first-principles calculations. Writing  information is performed using the electrostatic potential of scanning tunneling microscopy (STM). Reading information is based on the effect of the local magnetization induced at the zigzag graphene nanoribbon (Z-GNR) edge-saturated with oxygen or the hydroxy group-and can be realized with the use of giant magnetoresistance (GMR), a magnetic tunnel junction or spin-transfer torque devices. The energetic barriers for the hop forward and backward processes can be tuned by the distance and potential of the STM tip; this thus enables us to tailor the non-volatile logic states. The proposed system enables very dense packing of the logic cells and could be used in random access and flash memory devices. PMID:26596910

  12. Proton irradiation of liquid crystal based adaptive optical devices

    International Nuclear Information System (INIS)

    To assess its radiation hardness, a liquid crystal based adaptive optical element has been irradiated using a 60 MeV proton beam. The device with the functionality of an optical beam steerer was characterised before, during and after the irradiation. A systematic set of measurements on the transmission and beam deflection angles was carried out. The measurements showed that the transmission decreased only marginally and that its optical performance degraded only after a very high proton fluence (1010p/cm2). The device showed complete annealing in the functionality as a beam steerer, which leads to the conclusion that the liquid crystal technology for optical devices is not vulnerable to proton irradiation as expected in space.

  13. Measurement-device-independent entanglement-based quantum key distribution

    Science.gov (United States)

    Yang, Xiuqing; Wei, Kejin; Ma, Haiqiang; Sun, Shihai; Liu, Hongwei; Yin, Zhenqiang; Li, Zuohan; Lian, Shibin; Du, Yungang; Wu, Lingan

    2016-05-01

    We present a quantum key distribution protocol in a model in which the legitimate users gather statistics as in the measurement-device-independent entanglement witness to certify the sources and the measurement devices. We show that the task of measurement-device-independent quantum communication can be accomplished based on monogamy of entanglement, and it is fairly loss tolerate including source and detector flaws. We derive a tight bound for collective attacks on the Holevo information between the authorized parties and the eavesdropper. Then with this bound, the final secret key rate with the source flaws can be obtained. The results show that long-distance quantum cryptography over 144 km can be made secure using only standard threshold detectors.

  14. Small Dosimeter based on Timepix device for International Space Station

    Science.gov (United States)

    Turecek, D.; Pinsky, L.; Jakubek, J.; Vykydal, Z.; Stoffle, N.; Pospisil, S.

    2011-12-01

    The radiation environment in space is different, more complex and more intense than on Earth. Conventional devices and detection methods used nowadays do not allow to discriminate single particle types and the energy of the single particles. The Timepix detector is a position sensitive pixelated detector developed at CERN in a frame of the Medipix collaboration that provides capability to visualize tracks and measure energy of single particles. This information can be used for sorting the particles into different categories. It is possible to distinguish light charged particles such as electrons or heavy charged particles such as ions. Moreover, the Linear Energy Transfer (LET) for charged particles can be determined. Each category is assigned a quality factor corresponding to the energy a particle would deposit in the human tissue. By summing the dose of all particles an estimate of the dose rate can be calculated. For space dosimetry purposes a miniature device with the Timepix detector and a custom made integrated USB based readout interface has been constructed. The entire device has dimensions of a USB flash memory stick. The whole compact device is connected to a control PC and is operated continuously. The PC runs a software that controls data acquisition, adjusts the acquisition time adaptively according to the particle rate, analyzes the particle tracks, evaluates the deposited energy and the LET and visualizes in a simple display the estimated dose rate. The performance of the device will be tested during a mission on International Space Station planned towards the beginning of year 2012.

  15. A hyperlens-based device for nanoscale focusing of light

    Institute of Scientific and Technical Information of China (English)

    Jiangnan Zhao; Guoxing Zheng; Song Li; Hui Zhou; Yue Ma; Ruiying Zhang; Yah Shi; Ping'an He

    2012-01-01

    To resolve the problem of missed evanescent waves in a beam focusing system,a hyperlens-based beam focusing device is proposed in this letter.This device can convert the evanescent waves into propagating waves,and then a super-resolution spot is formed at the center of the hyperlens.The working principle of the device is presented,and the way in which the material and structural parameters of the hyperlens affect the resolution and transmission is analyzed in detail. A multibeam focusing device is optimally designed,and the simulated results verify that a nanoscale spot with a diameter of 15.6 nm (corresponding to λ0/24,where λ0 is the working wavelength in vacuum) is achieved,which is far less than the diffraction limited resolution with a value of 625 nm (l.7λ0).The device is expected to find numerous applications in optical data storage and nano-photolithography,among others.

  16. Optical sensor array platform based on polymer electronic devices

    Science.gov (United States)

    Koetse, Marc M.; Rensing, Peter A.; Sharpe, Ruben B. A.; van Heck, Gert T.; Allard, Bart A. M.; Meulendijks, Nicole N. M. M.; Kruijt, Peter G. M.; Tijdink, Marcel W. W. J.; De Zwart, René M.; Houben, René J.; Enting, Erik; van Veen, Sjaak J. J. F.; Schoo, Herman F. M.

    2007-10-01

    Monitoring of personal wellbeing and optimizing human performance are areas where sensors have only begun to be used. One of the reasons for this is the specific demands that these application areas put on the underlying technology and system properties. In many cases these sensors will be integrated in clothing, be worn on the skin, or may even be placed inside the body. This implies that flexibility and wearability of the systems is essential for their success. Devices based on polymer semiconductors allow for these demands since they can be fabricated with thin film technology. The use of thin film device technology allows for the fabrication of very thin sensors (e.g. integrated in food product packaging), flexible or bendable sensors in wearables, large area/distributed sensors, and intrinsically low-cost applications in disposable products. With thin film device technology a high level of integration can be achieved with parts that analyze signals, process and store data, and interact over a network. Integration of all these functions will inherently lead to better cost/performance ratios, especially if printing and other standard polymer technology such as high precision moulding is applied for the fabrication. In this paper we present an optical transmission sensor array based on polymer semiconductor devices made by thin film technology. The organic devices, light emitting diodes, photodiodes and selective medium chip, are integrated with classic electronic components. Together they form a versatile sensor platform that allows for the quantitative measurement of 100 channels and communicates wireless with a computer. The emphasis is given to the sensor principle, the design, fabrication technology and integration of the thin film devices.

  17. Control strategies for active lower extremity prosthetics and orthotics: a review

    OpenAIRE

    Tucker, M R; Olivier, J; Pagel, A; Bleuler, H.; Bouri, M.; Lambercy, O.; del R. Millan, J.; Riener, R.; Vallery, H; Gassert, R.

    2015-01-01

    Technological advancements have led to the development of numerous wearable robotic devices for the physical assistance and restoration of human locomotion. While many challenges remain with respect to the mechanical design of such devices, it is at least equally challenging and important to develop strategies to control them in concert with the intentions of the user. This work reviews the state-of-the-art techniques for controlling portable active lower limb prosthetic and orthotic (P/O) de...

  18. Prototyping Cognitive Prosthetics for People with Dementia

    Science.gov (United States)

    Davies, Richard; Nugent, Chris D.; Donnelly, Mark

    In the COGKNOW project, a cognitive prosthetic has been developed through the application of Information and Communication Technology (ICT)-based services to address the unmet needs and demands of persons with dementia. The primary aim of the developed solution was to offer guidance with conducting everyday activities for persons with dementia. To encourage a user-centred design process, a three-phased methodology was introduced to facilitate cyclical prototype development. At each phase, user input was used to guide the future development. As a prerequisite to the first phase of development, user requirements were gathered to identify a small set of functional requirements from which a number of services were identified. Following implementation of these initial services, the prototype was evaluated on a cohort of users and, through observing their experiences and recording their feedback, the design was refined and the prototype redeveloped to include a number of additional services in the second phase. The current chapter provides an overview of the services designed and developed in the first two phases.

  19. Internet-Based Device-Assisted Remote Monitoring of Cardiovascular Implantable Electronic Devices

    Science.gov (United States)

    Pron, G; Ieraci, L; Kaulback, K

    2012-01-01

    Executive Summary Objective The objective of this Medical Advisory Secretariat (MAS) report was to conduct a systematic review of the available published evidence on the safety, effectiveness, and cost-effectiveness of Internet-based device-assisted remote monitoring systems (RMSs) for therapeutic cardiac implantable electronic devices (CIEDs) such as pacemakers (PMs), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. The MAS evidence-based review was performed to support public financing decisions. Clinical Need: Condition and Target Population Sudden cardiac death (SCD) is a major cause of fatalities in developed countries. In the United States almost half a million people die of SCD annually, resulting in more deaths than stroke, lung cancer, breast cancer, and AIDS combined. In Canada each year more than 40,000 people die from a cardiovascular related cause; approximately half of these deaths are attributable to SCD. Most cases of SCD occur in the general population typically in those without a known history of heart disease. Most SCDs are caused by cardiac arrhythmia, an abnormal heart rhythm caused by malfunctions of the heart’s electrical system. Up to half of patients with significant heart failure (HF) also have advanced conduction abnormalities. Cardiac arrhythmias are managed by a variety of drugs, ablative procedures, and therapeutic CIEDs. The range of CIEDs includes pacemakers (PMs), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. Bradycardia is the main indication for PMs and individuals at high risk for SCD are often treated by ICDs. Heart failure (HF) is also a significant health problem and is the most frequent cause of hospitalization in those over 65 years of age. Patients with moderate to severe HF may also have cardiac arrhythmias, although the cause may be related more to heart pump or haemodynamic failure. The presence of HF, however

  20. Superconducting spintronic devices based on nanostructures ferromagnet/superconductor

    International Nuclear Information System (INIS)

    The layered nanostructures ferromagnet/superconductor (F/S) due to combination of incompatible in homogeneous materials properties are the most perspective materials for use in the new field of electronics - a superconducting spintronics. A new type of logical devices based on the layered F/S nanostructures and combining the advantages of the superconducting and magnetic recording channels in one sample is offered. Each channel can be separately controlled by weak magnetic field or current pulse and the switching time is of order of 10-10 - 10-11 s. The implementation of such devices on base of high-temperature superconductors will allow using nitrogen instead of expensive helium for cooling.

  1. Neural-Based Models of Semiconductor Devices for SPICE Simulator

    OpenAIRE

    Hanene B. Hammouda; Mongia Mhiri; Zièd Gafsi; Kamel Besbes

    2008-01-01

    The paper addresses a simple and fast new approach to implement Artificial Neural Networks (ANN) models for the MOS transistor into SPICE. The proposed approach involves two steps, the modeling phase of the device by NN providing its input/output patterns, and the SPICE implementation process of the resulting model. Using the Taylor series expansion, a neural based small-signal model is derived. The reliability of our approach is validated through simulations of some circuits in DC and small-...

  2. Network-based Fingerprint Authentication System Using a Mobile Device

    OpenAIRE

    Zhang, Qihu

    2016-01-01

    Abstract— Fingerprint-based user authentication is highly effective in networked services such as electronic payment, but conventional authentication solutions have problems in cost, usability and security. To resolve these problems, we propose a touch-less fingerprint authentication solution, in which a mobile device's built-in camera is used to capture fingerprint image, and then it is sent to the server to determine the identity of the user. We designed and implemented a prototype as an a...

  3. Graphene Electronic Device Based Biosensors and Chemical Sensors

    OpenAIRE

    Jiang, Shan

    2014-01-01

    Two-dimensional layered materials, such as graphene and MoS2, are emerging as an exciting material system for a new generation of atomically thin electronic devices. With their ultrahigh surface to volume ratio and excellent electrical properties, 2D-layered materials hold the promise for the construction of a generation of chemical and biological sensors with unprecedented sensitivity. In my PhD thesis, I mainly focus on graphene based electronic biosensors and chemical sensors. In the first...

  4. Memory devices based on organic electric bistable materials

    Institute of Scientific and Technical Information of China (English)

    CHEN Qi; BAI Hua; SHI GaoQuan

    2007-01-01

    Organic/metallic composites have demonstrated electrical bistability, as well as memory effects. These advanced materials have shown potential applications in digital information storage because of their good stability, flexibility and fast response speed. The electric bistability phenomenon can be explained by electric field-induced electron transfer/storage. This article reviews the recent progress of memory devices based on organic/metallic and polymeric composites with electric bistability.

  5. A thermal logic device based on fluid-solid interfaces

    OpenAIRE

    Murad, Sohail; Puri, Ishwar K.

    2013-01-01

    Thermal rectification requires that thermal conductivity not be a separable function of position and temperature. Investigators have considered inhomogeneous solids to design thermal rectifiers but manipulations of solid lattices are energy intensive. We propose a thermal logic device based on asymmetric solid-fluid resistances that couples two fluid reservoirs separated by solid-fluid interfaces. It is the thermal analog of a three terminal transistor, the hot reservoir being the emitter, th...

  6. Optical sensor array platform based on polymer electronic devices

    OpenAIRE

    Koetse, M.M.; Rensing, P.A.; Sharpe, R.B.A.; Heck, G.T. van; Allard, B.A.M.; Meulendijks, N.N.M.M.; Kruijt, P.G.M.; Tijdink, M.W.W.J.; Zwart, R.M. de; Houben, R.J.; Enting, E.; Veen, S.J.J.F. van; Schoo, H.F.M.

    2007-01-01

    Monitoring of personal wellbeing and optimizing human performance are areas where sensors have only begun to be used. One of the reasons for this is the specific demands that these application areas put on the underlying technology and system properties. In many cases these sensors will be integrated in clothing, be worn on the skin, or may even be placed inside the body. This implies that flexibility and wearability of the systems is essential for their success. Devices based on polymer semi...

  7. Simulation of devices based on carbon nanotubes and graphene

    Science.gov (United States)

    Abramov, I. I.; Labunov, V. A.; Kolomejtseva, N. V.; Romanova, I. A.

    2014-12-01

    The simulation results of different devices based on carbon nanotubes (CNT) and graphene are described in the paper. The combined numerical model of hybrid integrated structures including resonant tunneling diode and field-effect transistor (RTD-FET) is proposed. Simulation of RTD-FET based on CNT of different types (chirality) was realized with the use of the developed model. The technique of express simulation of nanoradio based on CNT of the type I (based on only single CNT) and of the type II (hybrid radio) is developed. Proposed models can be used for calculation of nanoradio characteristics such as: 1) resonant frequency of CNT; 2) oscillation amplitude of CNT; 3) CNT IV-characteristics depending on different factors. Results of device simulation based on single-wall and multi-wall CNT are given in the paper. IV-characteristics of nanoscale resonant tunneling structure based on graphene-on-SiC were calculated. As well as it was investigated the influence of different parameters on the electrical characteristic of graphene-based nanostructures.

  8. Microcontact printing-based fabrication of digital microfluidic devices.

    Science.gov (United States)

    Watson, Michael W L; Abdelgawad, Mohamed; Ye, George; Yonson, Neal; Trottier, Justin; Wheeler, Aaron R

    2006-11-15

    Digital microfluidics is a fluid manipulation technique in which discrete droplets are actuated on patterned arrays of electrodes. Although there is great enthusiasm for the application of this technique to chemical and biological assays, development has been hindered by the requirement of clean room fabrication facilities. Here, we present a new fabrication scheme, relying on microcontact printing (microCP), an inexpensive technique that does not require clean room facilities. In microCP, an elastomeric poly(dimethylsiloxane) stamp is used to deposit patterns of self-assembled monolayers onto a substrate. We report three different microCP-based fabrication techniques: (1) selective etching of gold-on-glass substrates; (2) direct printing of a suspension of palladium colloids; and (3) indirect trapping of gold colloids from suspension. In method 1, etched gold electrodes are used for droplet actuation; in methods 2 and 3, colloid patterns are used to seed electroless deposition of copper. We demonstrate, for the first time, that digital microfluidic devices can be formed by microCP and are capable of the full range of digital microfluidics operations: dispensing, merging, motion, and splitting. Devices formed by the most robust of the new techniques were comparable in performance to devices formed by conventional methods, at a fraction of the fabrication time. These new techniques for digital microfluidics device fabrication have the potential to facilitate expansion of this technology to any research group, even those without access to conventional microfabrication tools and facilities. PMID:17105183

  9. Strain-Engineering of Graphene Based Topological Quantum Devices

    Science.gov (United States)

    Diniz, Ginetom S.; Guassi, Marcos R.; Qu, Fanyao

    2015-03-01

    We have investigated the spin-charge transport in quantum devices based on graphene nanoribbons (GNR). Our calculation is based on the surface Green's function technique, considering the presence of an uniform uniaxial strain, spin-orbit interactions (SOIs), exchange field and a smooth staggered potential. We propose the use of uniaxial strain as an efficient mechanism to tune the conductance profiles of GNR with different edge terminations. Our results show that distinct behaviors can be achieved: for armchair GNR there is a complete suppression of the conductance close to the Fermi level with the formation of a band gap that depends on the direction and strength of the strain deformation, while for zigzag GNR there is only a small conductance suppression. We also discuss the effects of SOIs and the appearance of spin-resolved conductance oscillations, and the local density of states of these GNR devices in the quantum anomalous Hall regime. Furthermore, we demonstrate that the local density of states show that depending on the smoothness of the staggered potential, the edge states of AGNR can either emerge or be suppressed. These emerging states can be probed by scanning tunneling microscope. Our findings can be potentially used in novel GNR based topological quantum devices. Supported by FAP-DF, CNPq and CAPES.

  10. An UV photochromic memory effect in proton-based WO3 electrochromic devices

    International Nuclear Information System (INIS)

    We report an UV photochromic memory effect on a standard proton-based WO3 electrochromic device. It exhibits two memory states, associated with the colored and bleached states of the device, respectively. Such an effect can be used to enhance device performance (increasing the dynamic range), re-energize commercial electrochromic devices, and develop memory devices

  11. A cloud-based multimodality case file for mobile devices.

    Science.gov (United States)

    Balkman, Jason D; Loehfelm, Thomas W

    2014-01-01

    Recent improvements in Web and mobile technology, along with the widespread use of handheld devices in radiology education, provide unique opportunities for creating scalable, universally accessible, portable image-rich radiology case files. A cloud database and a Web-based application for radiologic images were developed to create a mobile case file with reasonable usability, download performance, and image quality for teaching purposes. A total of 75 radiology cases related to breast, thoracic, gastrointestinal, musculoskeletal, and neuroimaging subspecialties were included in the database. Breast imaging cases are the focus of this article, as they best demonstrate handheld display capabilities across a wide variety of modalities. This case subset also illustrates methods for adapting radiologic content to cloud platforms and mobile devices. Readers will gain practical knowledge about storage and retrieval of cloud-based imaging data, an awareness of techniques used to adapt scrollable and high-resolution imaging content for the Web, and an appreciation for optimizing images for handheld devices. The evaluation of this software demonstrates the feasibility of adapting images from most imaging modalities to mobile devices, even in cases of full-field digital mammograms, where high resolution is required to represent subtle pathologic features. The cloud platform allows cases to be added and modified in real time by using only a standard Web browser with no application-specific software. Challenges remain in developing efficient ways to generate, modify, and upload radiologic and supplementary teaching content to this cloud-based platform. Online supplemental material is available for this article. PMID:24819664

  12. Electrochemiluminescence detection in microfluidic cloth-based analytical devices.

    Science.gov (United States)

    Guan, Wenrong; Liu, Min; Zhang, Chunsun

    2016-01-15

    This work describes the first approach at combining microfluidic cloth-based analytical devices (μCADs) with electrochemiluminescence (ECL) detection. Wax screen-printing is employed to make cloth-based microfluidic chambers which are patterned with carbon screen-printed electrodes (SPEs) to create truly disposable, simple, inexpensive sensors which can be read with a low-cost, portable charge coupled device (CCD) imaging sensing system. And, the two most commonly used ECL systems of tris(2,2'-bipyridyl)ruthenium(II)/tri-n-propylamine (Ru(bpy)3(2+)/TPA) and 3-aminophthalhydrazide/hydrogen peroxide (luminol/H2O2) are applied to demonstrate the quantitative ability of the ECL μCADs. In this study, the proposed devices have successfully fulfilled the determination of TPA with a linear range from 2.5 to 2500μM with a detection limit of 1.265μM. In addition, the detection of H2O2 can be performed in the linear range of 0.05-2.0mM, with a detection limit of 0.027mM. It has been shown that the ECL emission on the wax-patterned cloth device has an acceptable sensitivity, stability and reproducibility. Finally, the applicability of cloth-based ECL is demonstrated for determination of glucose in phosphate buffer solution (PBS) and artificial urine (AU) samples, with the detection limits of 0.032mM and 0.038mM, respectively. It can be foreseen, therefore, that μCADs with ECL detection could provide a new sensing platform for point-of-care testing, public health, food safety detection and environmental monitoring in remote regions, developing or developed countries. PMID:26319168

  13. Mesofluidic controlled robotic or prosthetic finger

    Science.gov (United States)

    Lind, Randall F; Jansen, John F; Love, Lonnie J

    2013-11-19

    A mesofluidic powered robotic and/or prosthetic finger joint includes a first finger section having at least one mesofluidic actuator in fluid communication with a first actuator, a second mesofluidic actuator in fluid communication with a second actuator and a second prosthetic finger section pivotally connected to the first finger section by a joint pivot, wherein the first actuator pivotally cooperates with the second finger to provide a first mechanical advantage relative to the joint point and wherein the second actuator pivotally cooperates with the second finger section to provide a second mechanical advantage relative to the joint point.

  14. Telemedicine Based on Mobile Devices and Mobile Cloud Computing

    Directory of Open Access Journals (Sweden)

    Lidong Wang

    2014-04-01

    Full Text Available Mobile devices such as smartphones and tablets support kinds of mobile computing and services. They can access to the cloud or offload the computation-intensive part to the cloud computing resources. Mobile cloud computing (MCC integrates the cloud computing into the mobile environment, which extends mobile devices’ battery lifetime, improves their data storage capacity and processing power, and improves their reliability and information security. In this paper, the applications of smartphones in telemedicine and MCC-based telemedicine were presented. Issues on the information security of smartphones and tablets, challenges of smartphones in telemedicine and challenges of MCC-based telemedicine were also introduced.

  15. Analysis of Android Device-Based Solutions for Fall Detection.

    Science.gov (United States)

    Casilari, Eduardo; Luque, Rafael; Morón, María-José

    2015-01-01

    Falls are a major cause of health and psychological problems as well as hospitalization costs among older adults. Thus, the investigation on automatic Fall Detection Systems (FDSs) has received special attention from the research community during the last decade. In this area, the widespread popularity, decreasing price, computing capabilities, built-in sensors and multiplicity of wireless interfaces of Android-based devices (especially smartphones) have fostered the adoption of this technology to deploy wearable and inexpensive architectures for fall detection. This paper presents a critical and thorough analysis of those existing fall detection systems that are based on Android devices. The review systematically classifies and compares the proposals of the literature taking into account different criteria such as the system architecture, the employed sensors, the detection algorithm or the response in case of a fall alarms. The study emphasizes the analysis of the evaluation methods that are employed to assess the effectiveness of the detection process. The review reveals the complete lack of a reference framework to validate and compare the proposals. In addition, the study also shows that most research works do not evaluate the actual applicability of the Android devices (with limited battery and computing resources) to fall detection solutions. PMID:26213928

  16. Analysis of Android Device-Based Solutions for Fall Detection

    Directory of Open Access Journals (Sweden)

    Eduardo Casilari

    2015-07-01

    Full Text Available Falls are a major cause of health and psychological problems as well as hospitalization costs among older adults. Thus, the investigation on automatic Fall Detection Systems (FDSs has received special attention from the research community during the last decade. In this area, the widespread popularity, decreasing price, computing capabilities, built-in sensors and multiplicity of wireless interfaces of Android-based devices (especially smartphones have fostered the adoption of this technology to deploy wearable and inexpensive architectures for fall detection. This paper presents a critical and thorough analysis of those existing fall detection systems that are based on Android devices. The review systematically classifies and compares the proposals of the literature taking into account different criteria such as the system architecture, the employed sensors, the detection algorithm or the response in case of a fall alarms. The study emphasizes the analysis of the evaluation methods that are employed to assess the effectiveness of the detection process. The review reveals the complete lack of a reference framework to validate and compare the proposals. In addition, the study also shows that most research works do not evaluate the actual applicability of the Android devices (with limited battery and computing resources to fall detection solutions.

  17. Polymer-based waveguide devices for WDM applications

    Science.gov (United States)

    Viens, Jean-Francois; Callender, Claire L.; Noad, Julian P.; Eldada, Louay A.; Norwood, Robert A.

    1999-10-01

    This paper summarizes the work currently in progress at CRC Canada on wavelength multiplexing components based on polymer waveguide devices for operation at 1550 nm. Planar arrayed waveguide gratings (AWGs) of various bandwidths were designed, fabricated and tested using acrylate polymer materials developed by Allied Signal Inc. Eight channel polymer demultiplexers fabricated by standard lithography show on-chip losses of 8 dB and a crosstalk of -25 dB between channels spaced 1.6 nm part. Owing to the thermo- optic properties of these polymers, the spectral response of the device scan be tuned by more than 7 nm without changes in optical crosstalk or on-chip loss. Very compact AWGs made with Allied Signal polymers are being designed and tested to address the need for cost effective, high bandwidth optical components in the telecom and datacom industries.

  18. Opto-electronic transport properties of graphene oxide based devices

    International Nuclear Information System (INIS)

    Large area, solution-processed, graphene oxide (GO)nanocomposite based photo FET has been successfully fabricated. The device exhibits p-type charge transport characteristics in dark condition. Our measurements indicate that the transport characteristics are gate dependent and extremely sensitive to solar light. Photo current decay mechanism of GO is well explained and is associated with two phenomena: a) fast response process and b) slow response process. Slow response photo decay can be considered as the intrinsic phenomena which are present for both GO and reduced GO (r-GO), whereas the first response photo decay is controlled by the surface defect states. Demonstration of photo FET performance of GO thin film is a significant step forward in integrating these devices in various optoelectronic circuits

  19. Cyclops – Snapshot Translation System Based on Mobile Device

    Directory of Open Access Journals (Sweden)

    Fai Wong

    2011-08-01

    Full Text Available This paper presents an implementation of Cyclops, a snapshot translation system. It realizes the translation of textural information being captured as an image via the digital camera of a mobile device. The design framework of Cyclops is targeted at providing user the most comprehensive interface in using language translation tool to access the meaning of non-native text in a more natural and efficient way. Currently, it supports the translation of languages from Chinese to Portuguese and English. On the other hand, user can escape from the difficulty in using keyboard to input any non-alphabetic language such as Chinese. In the course of realization of this system, several technical challenges were encountered. It has been developed based on the technologies of image processing, optical character recognition (OCR, and machine translation (MT. Most importantly, the system is designed to run on the common usage mobile devices which have memory and storage limitations.

  20. Redefining prosthetic ankle mechanics: non-anthropomorphic ankle design.

    Science.gov (United States)

    LaPrè, Andrew K; Sup, Frank

    2013-06-01

    The moment transferred at the residual limb socket interface of transtibial amputees can be a limiting factor of the comfort and activity level of lower limb amputees. The high pressures seen can be a significant source of pain, as well as result in deep tissue damage. The compensation of the sound limbs causes an asymmetrical gait which can be a contributor of early onset osteoarthritis in the sound limbs. It has been shown that the moment transferred with conventional passive prostheses can be lowered in magnitude by aligning the tibia with ground reaction forces, but this limits the effectiveness of the device. With recent powered prosthetics designed to mimic the missing limb, power can be injected into the gait cycle, but can also be limited by this pressure threshold. This paper shows the results of calculations that suggest that altering the prosthetic ankle mechanism can reduce the socket interface moments by as much as 50%. This supports the development of an active non-anthropomorphic ankle prosthesis which reduces socket interface moments while still injecting substantial power levels into the gait cycle. PMID:24187257

  1. Physically-based modelling of polycrystalline semiconductor devices

    International Nuclear Information System (INIS)

    Thin-film technology using polycrystalline semiconductors has been widely applied to active-matrix-addressed liquid crystal displays (AMLCDs) where thin-film transistors act as digital pixel switches. Research and development is in progress to integrate the driver circuits around the peripheral of the display, resulting in significant cost reduction of connections between rows and columns and the peripheral circuitry. For this latter application, where for instance it is important to control the greyscale voltage level delivered to the pixel, an understanding of device behaviour is required so that models can be developed for analogue circuit simulation. For this purpose, various analytical models have been developed based on that of Seto who considered the effect of monoenergetic trap states and grain boundaries in polycrystalline materials but not the contribution of the grains to the electrical properties. The principal aim of this thesis is to describe the use of a numerical device simulator (ATLAS) as a tool to investigate the physics of the trapping process involved in the device operation, which additionally takes into account the effect of multienergetic trapping levels and the contribution of the grain into the modelling. A study of the conventional analytical models is presented, and an alternative approach is introduced which takes into account the grain regions to enhance the accuracy of the analytical modelling. A physically-based discrete-grain-boundary model and characterisation method are introduced to study the effects of the multienergetic trap states on the electrical characteristics of poly-TFTs using CdSe devices as the experimental example, and the electrical parameters such as the density distribution of the trapping states are extracted. The results show excellent agreement between the simulation and experimental data. The limitations of this proposed physical model are also studied and discussed. (author)

  2. An electromagnetic inerter-based vibration suppression device

    Science.gov (United States)

    Gonzalez-Buelga, A.; Clare, L. R.; Neild, S. A.; Jiang, J. Z.; Inman, D. J.

    2015-05-01

    This paper describes how an inerter-based device for structural vibration suppression can be realized using an electromagnetic transducer such as a linear motor. When the motor shaft moves, a difference of voltage is generated across the transducer coil. The voltage difference is proportional to the relative velocity between its two terminals. The electromagnetic transducer will exert a force proportional to current following the Lorentz principle if the circuit is closed around the transducer coil. If an electronic circuit consisting of a capacitor, an inductance and a resistance with the appropriate configuration is connected, the resulting force reflected back into the mechanical domain is equivalent to that achieved by a mechanical inerter-based device. The proposed configuration is easy to implement and very versatile, provided a high quality conversion system with negligible losses. With the use of electromagnetic devices, a new generation of vibration absorbers can be realized, for example in the electrical domain it would be relatively uncomplicated to synthesize multi-frequency or real time tunable vibration absorbers by adding electrical components in parallel. In addition by using resistance emulators in the electrical circuits, part of the absorbed vibration energy can be converted into usable power. Here an electromagnetic tuned inerter damper (E-TID) is tested experimentally using real time dynamic substructuring. A voltage compensation unit was developed in order to compensate for coil losses. This voltage compensation unit requires power, which is acquired through harvesting from the vibration energy using a resistance emulator. A power balance analysis was developed in order to ensure the device can be self sufficient. Promising experimental results, using this approach, have been obtained and are presented in this paper. The ultimate goal of this research is the development of autonomous electromagnetic vibration absorbers, able to harvest energy

  3. Sensor-based user interface concepts for continuous, around-device and gestural interaction on mobile devices

    OpenAIRE

    Kratz, Sven

    2012-01-01

    A generally observable trend of the past 10 years is that the amount of sensors embedded in mobile devices such as smart phones and tablets is rising steadily. Arguably, the available sensors are mostly underutilized by existing mobile user interfaces. In this dissertation, we explore sensor-based user interface concepts for mobile devices with the goal of making better use of the available sensing capabilities on mobile devices as well as gaining insights on the types of sensor technologies ...

  4. The Prosthetic Experience Between Body and Technology

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2016-01-01

    In this paper, I argue that a prosthetic aesthetic instigated by experimental art practices operate with and within a ‘second nature’ – in-between science and art. Drawing on theories from Dewey and Edelman and examples from Da Vinci, Brancusi, Man Ray, Dali and Stelarc, I am calling for an...

  5. 基于动态阈值的肌电假手动作控制方法研究%Movement Pattern Control for Prosthetic Hand Based on a Method of Dynamic Threshold

    Institute of Scientific and Technical Information of China (English)

    喻洪流; 胡加华

    2011-01-01

    由于构成肌电信号采集电路的电子元器件性能不可能完全对称及干扰信号的存在,有时会导致两路肌电信号发生阈值不一致。这时仍采用固定阈值来对两路肌电信号控制的动作进行判别,会导致动作的误判率增加。为了提高对假手动作判别的正确率,本文提出了利用动态阈值对假手动作进行判别。实验结果表明,利用动态阈值对假手动作进行判别,能够提高对动作判别的正确率达约10%。%Due to the function asymmetry of electrical components used for EMG signal acquisition circuit and the existing of undesired signals, sometimes thresholds for judging EMG's occur may be incongruent. If a fixed threshold is used to recognize Prosthetic Hand's movement,the matching rate of prosthetic hand's movement pattern recognition will be increased. In order to improve prosthetic hand's movement pattern recognition, a method of dynamic threshold was used to recognize the prosthetic hand's movement. The exprimental results showed that the method of dynamic threshold can obviously improve Prosthetic Hand's movement pattern recognition by about 10%.

  6. Physically based molecular device model in a transient circuit simulator

    International Nuclear Information System (INIS)

    Two efficient, physically based models for the real-time simulation of molecular device characteristics of single molecules are developed. These models assume that through-molecule tunnelling creates a steady-state Lorentzian distribution of excess electron density on the molecule and provides for smooth transitions for the electronic degrees of freedom between the tunnelling, molecular-excitation, and charge-hopping transport regimes. They are implemented in the fREEDATM transient circuit simulator to allow for the full integration of nanoscopic molecular devices in standard packages that simulate entire devices including CMOS circuitry. Methods are presented to estimate the parameters used in the models via either direct experimental measurement or density-functional calculations. The models require 6-8 orders of magnitude less computer time than do full a priori simulations of the properties of molecular components. Consequently, molecular components can be efficiently implemented in circuit simulators. The molecular-component models are tested by comparison with experimental results reported for 1,4-benzenedithiol

  7. MEMS- and NEMS-based smart devices and systems

    Science.gov (United States)

    Varadan, Vijay K.

    2001-11-01

    structures and food and medical industries. This unique combination of technologies also results in novel conformal sensors that can be remotely sensed by an antenna system with the advantage of no power requirements at the sensor site. This paper provides a brief review of MEMS and NEMS based smart systems for various applications mentioned above. Carbon Nano Tubes (CNT) with their unique structure, have already proven to be valuable in their application as tips for scanning probe microscopy, field emission devices, nanoelectronics, H2-storage, electromagnetic absorbers, ESD, EMI films and coatings and structural composites. For many of these applications, highly purified and functionalized CNT which are compatible with many host polymers are needed. A novel microwave CVD processing technique to meet these requirements has been developed at Penn State Center for the engineering of Electronic and Acoustic Materials and Devices (CEEAMD). This method enables the production of highly purified carbon nano tubes with variable size (from 5-40 nm) at low cost (per gram) and high yield. Whereas, carbon nano tubes synthesized using the laser ablation or arc discharge evaporation method always include impurity due to catalyst or catalyst support. The Penn State research is based on the use of zeolites over other metal/metal oxides in the microwave field for a high production and uniformity of the product. An extended conventional purification method has been employed to purify our products in order to remove left over impurity. A novel composite structure can be tailored by functionalizing carbon nano tubes and chemically bonding them with the polymer matrix e.g. block or graft copolymer, or even cross- linked copolymer, to impart exceptional structural, electronic and surface properties. Bio- and Mechanical-MEMS devices derived from this hybrid composites will be presented.

  8. Mashup Based Content Search Engine for Mobile Devices

    OpenAIRE

    Kohei Arai

    2013-01-01

    Mashup based content search engine for mobile devices is proposed. Example of the proposed search engine is implemented with Yahoo!JAPAN Web SearchAPI, Yahoo!JAPAN Image searchAPI, YouTube Data API, and Amazon Product Advertising API. The retrieved results are also merged and linked each other. Therefore, the different types of contents can be referred once an e-learning content is retrieved. The implemented search engine is evaluated with 20 students. The results show usefulness and effectiv...

  9. Mashup Based Content Search Engine for Mobile Devices

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2013-05-01

    Full Text Available Mashup based content search engine for mobile devices is proposed. Example of the proposed search engine is implemented with Yahoo!JAPAN Web SearchAPI, Yahoo!JAPAN Image searchAPI, YouTube Data API, and Amazon Product Advertising API. The retrieved results are also merged and linked each other. Therefore, the different types of contents can be referred once an e-learning content is retrieved. The implemented search engine is evaluated with 20 students. The results show usefulness and effectiveness on e-learning content searches with a variety of content types, image, document, pdf files, moving picture.

  10. Neural-Based Models of Semiconductor Devices for SPICE Simulator

    Directory of Open Access Journals (Sweden)

    Hanene B. Hammouda

    2008-01-01

    Full Text Available The paper addresses a simple and fast new approach to implement Artificial Neural Networks (ANN models for the MOS transistor into SPICE. The proposed approach involves two steps, the modeling phase of the device by NN providing its input/output patterns, and the SPICE implementation process of the resulting model. Using the Taylor series expansion, a neural based small-signal model is derived. The reliability of our approach is validated through simulations of some circuits in DC and small-signal analyses.

  11. Development of the Embedded Protective Device Based on ARM

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-wen; LI Na; PAN Chun-de

    2005-01-01

    An embedded protective device for 35kV power line is worked out based on Philips' LPC2292 ARM MCU. Several aspects such as embedded design technique adopted in the system framework, application of adaptive theory in data acquisition, Board Support Packet (BSP) developing and task dispatching related to operating system are discussed. Both hardware and software framework of the system are given. Advanced hardware platform and software development environment is applied in design of the system, with the advanced co-design technology.

  12. A Silicon-Based Ferroelectric Capacitor for Memory Devices

    Institute of Scientific and Technical Information of China (English)

    任天令; 张林涛; 刘理天; 李志坚

    2002-01-01

    We study a silicon-based Pb TiO3/Pb(Zro.53 Tio.47)O3/Pb TiO3 capacitor, prepared by an improved sol-gel method.The ferroelectric capacitor has a high remanent polarization of 15 pC/crm2 at a coercive field of about 30 k V/cm,an ultra-low leakage current density of 0.1 hA/crm2, and almost fatigue free properties. It can be used as a promising candidate for ferroelectric memory devices.

  13. Lanthanide oxides thin films for graphene-based devices

    International Nuclear Information System (INIS)

    We study the application potential of gadolinium and dysprosium oxide for graphene-based devices. Lanthanide oxide thin films of defined thickness are deposited in the presence of oxygen as well as nitrogen at 400 C by thermal CVD on an n+-Si(100) substrate. The roughness of the films is determined by atomic force micrographs and the thickness by cross-section scanning electron microscopy. A breakdown field in the range of 0.3 Vnm-1 is determined by I-V measurements for both rare earth oxides. From C-V measurements at 1 MHz the dielectric constant of Gd2O3 (εr=9) and Dy2O3 (εr=8) are extracted. Since the dielectric constant of the rare earth oxides are higher compared to SiO2 we expect an improved screening of charged impurities and therefore an improved performance for graphene-based devices due to the oxides. By using a Fresnel-law based model the contrast of graphene is calculated as a function of wavelength for different oxide thicknesses and compared to optical and atomic force micrographs of exfoliated graphene on Gd2O3 and Dy2O3.

  14. Microchip-based Devices for Molecular Diagnosis of Genetic Diseases.

    Science.gov (United States)

    Cheng; Fortina; Surrey; Kricka; Wilding

    1996-09-01

    Microchips, constructed with a variety of microfabrication technologies (photolithography, micropatterning, microjet printing, light-directed chemical synthesis, laser stereochemical etching, and microcontact printing) are being applied to molecular biology. The new microchip-based analytical devices promise to solve the analytical problems faced by many molecular biologists (eg, contamination, low throughput, and high cost). They may revolutionize molecular biology and its application in clinical medicine, forensic science, and environmental monitoring. A typical biochemical analysis involves three main steps: (1) sample preparation, (2) biochemical reaction, and (3) detection (either separation or hybridization may be involved) accompanied by data acquisition and interpretation. The construction of a miniturized analyzer will therefore necessarily entail the miniaturization and integration of all three of these processes. The literature related to the miniaturization of these three processes indicates that the greatest emphasis so far is on the investigation and development of methods for the detection of nucleic acid, followed by the optimization of a biochemical reaction, such as the polymerase chain reaction. The first step involving sample preparation has received little attention. In this review the state of the art of, microchip-based, miniaturized analytical processes (eg, sample preparation, biochemical reaction, and detection of products) are outlined and the applications of microchip-based devices in the molecular diagnosis of genetic diseases are discussed. PMID:10462559

  15. A Survey on Location Based Authentication Protocols For Mobile Devices

    Directory of Open Access Journals (Sweden)

    Smruti. P. Patil

    2013-02-01

    Full Text Available As per the recent studies, the volatile growth has been seen inthe use of mobile devices as the supporting technology foraccessing Internet based services, as well as for personalcommunication needs in networking. Various studies indicatethat it is impossible to utilize strong cryptographic functions forimplementing security protocols on mobile devices. Ourresearch negates this. Explicitly, a performance analysis focusedon the most commonly used cryptographic protocols based onthe location address (latitude & longitude of the user for mobileapplications and anticipated provably secure authenticationprotocol that is more efficient than any of the existingauthentication protocol is being discussed in this paper.Understanding the use of public key cryptography which makespotential use of discrete logarithms problem. The security ofECC depends on the difficulty of Elliptic Curve DiscreteLogarithm. To provide secure communication for mobiledevices, authenticated protocol is an important primitive forestablishing trusted connection. In this paper, it has beenstudied that the location based system provides a better securityand acquires much less energy consumption than the existingauthentication protocols.

  16. A Graphical Password Based System for Small Mobile Devices

    Directory of Open Access Journals (Sweden)

    Wazir Zada Khan

    2011-09-01

    Full Text Available Passwords provide security mechanism for authentication and protection services against unwanted access to resources. A graphical based password is one promising alternatives of textual passwords. According to human psychology, humans are able to remember pictures easily. In this paper, we have proposed a new hybrid graphical password based system, which is a combination of recognition and recall based techniques that offers many advantages over the existing systems and may be more convenient for the user. Our scheme is resistant to shoulder surfing attack and many other attacks on graphical passwords. This scheme is proposed for smart mobile devices (like smart phones i.e. ipod, iphone, PDAs etc which are more handy and convenient to use than traditional desktop computer systems.

  17. A Graphical Password Based System for Small Mobile Devices

    CERN Document Server

    Khan, Wazir Zada; Xiang, Yang

    2011-01-01

    Passwords provide security mechanism for authentication and protection services against unwanted access to resources. A graphical based password is one promising alternatives of textual passwords. According to human psychology, humans are able to remember pictures easily. In this paper, we have proposed a new hybrid graphical password based system, which is a combination of recognition and recall based techniques that offers many advantages over the existing systems and may be more convenient for the user. Our scheme is resistant to shoulder surfing attack and many other attacks on graphical passwords. This scheme is proposed for smart mobile devices (like smart phones i.e. ipod, iphone, PDAs etc) which are more handy and convenient to use than traditional desktop computer systems.

  18. Influence of rectification procedure on the counter-torque force of prosthetic screws of implant-retained frameworks

    OpenAIRE

    Mauro Antonio de Arruda Nobilo; Guilherme Elias Pessanha Henrique; Wagner Sotero Fragoso; Ana Carolina Masarolo Machado; Luiz Gustavo Dias Daroz; Marcelo Ferraz Mesquita

    2008-01-01

    Objective: To evaluate the counter-force of prosthetic screws before and after the rectification procedure of the seating base of prosthetic framework screws. Methods: With a metal matrix containing three replicas of conical abutments (Micro-Unit; Conexão) placed at 10 mm from center to center, ten multiple cast structures were made of a titanium monoblock. The multiple cast structures were fastened onto the metal matrix abutments with a torque of 10 NCm. The screwing sequence was performed f...

  19. Diagnostic performance of FDG PET or PET/CT in prosthetic infection after arthroplasty: a meta-analysis

    International Nuclear Information System (INIS)

    The purpose of this study was to systematically review and perform a meta-analysis of published data regarding the diagnostic performance of positron emission tomography (PET) or PET/computed tomography (PET/CT) in prosthetic infection after arthroplasty. A comprehensive computer literature search of studies published through May 31, 2012 regarding PET or PET/CT in patients suspicious of prosthetic infection was performed in PubMed/MEDLINE, Embase and Scopus databases. Pooled sensitivity and specificity of PET or PET/CT in patients suspicious of prosthetic infection on a per prosthesis-based analysis were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of PET or PET/CT in patients with suspicious of prosthetic infection. Fourteen studies comprising 838 prosthesis with suspicious of prosthetic infection after arthroplasty were included in this meta-analysis. The pooled sensitivity of PET or PET/CT in detecting prosthetic infection was 86% (95% confidence interval [CI] 82-90%) on a per prosthesis-based analysis. The pooled specificity of PET or PET/CT in detecting prosthetic infection was 86% (95% CI 83-89%) on a per prosthesis-based analysis. The area under the ROC curve was 0.93 on a per prosthesis-based analysis. In patients suspicious of prosthetic infection, FDG PET or PET/CT demonstrated high sensitivity and specificity. FDG PET or PET/CT are accurate methods in this setting. Nevertheless, possible sources of false positive results and influcing factors should kept in mind.

  20. Nanoscale devices based on plasmonic coaxial waveguide resonators

    Science.gov (United States)

    Mahigir, A.; Dastmalchi, P.; Shin, W.; Fan, S.; Veronis, G.

    2015-02-01

    Waveguide-resonator systems are particularly useful for the development of several integrated photonic devices, such as tunable filters, optical switches, channel drop filters, reflectors, and impedance matching elements. In this paper, we introduce nanoscale devices based on plasmonic coaxial waveguide resonators. In particular, we investigate threedimensional nanostructures consisting of plasmonic coaxial stub resonators side-coupled to a plasmonic coaxial waveguide. We use coaxial waveguides with square cross sections, which can be fabricated using lithography-based techniques. The waveguides are placed on top of a silicon substrate, and the space between inner and outer coaxial metals is filled with silica. We use silver as the metal. We investigate structures consisting of a single plasmonic coaxial resonator, which is terminated either in a short or an open circuit, side-coupled to a coaxial waveguide. We show that the incident waveguide mode is almost completely reflected on resonance, while far from the resonance the waveguide mode is almost completely transmitted. We also show that the properties of the waveguide systems can be accurately described using a single-mode scattering matrix theory. The transmission and reflection coefficients at waveguide junctions are either calculated using the concept of the characteristic impedance or are directly numerically extracted using full-wave three-dimensional finite-difference frequency-domain simulations.

  1. New Evolving Directions for Device Performance Optimization Based Integration of Compound Semiconductor Devices on Silicon

    OpenAIRE

    Partha Mukhopadhyay; Palash Das; Chang, Edward Y.; Dhrubes Biswas

    2011-01-01

    Rapid advances in Compound Semiconductor (CS) technologies over last several decades have lead to high performances in peak power, power added efficiency (PAE) and linearity, but these devices are not amenable for integration on mainstream silicon technologies. A strategic direction has been presented for the growth of CS devices on silicon with challenges abounding in scalability, compatibility and cost effectiveness while extracting optimized device performances. The approach at IIT Kharagp...

  2. 21 CFR 888.3045 - Resorbable calcium salt bone void filler device.

    Science.gov (United States)

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3045 Resorbable calcium... are caused by trauma or surgery and are not intrinsic to the stability of the bony structure....

  3. Perspectives on embodiment and prosthetic incorporation in those with spinal cord injury: Comment on "The embodiment of assistive devices-from wheelchair to exoskeleton" by M. Pazzaglia and M. Molinari

    Science.gov (United States)

    Cole, Jonathan

    2016-03-01

    Pazzaglia's group is introducing contemporary cognitive neuroscience research into rehabilitation after spinal cord injury (SCI), in novel ways [5]. And, importantly, this work also overlaps with the priorities of patients. In a recent statement from the UK James Lind Alliance (which sets aims for research between professionals and patients), their top priority was: 'whether activity based rehabilitation, including functional electrical stimulation coupled with physical activity and hydrotherapy, improved outcomes after SCI?' [3]. It is a propitious time for cognitive science and rehabilitation to come together.

  4. Quantum-based electronic devices and systems selected topics in electronics and systems, v.14

    CERN Document Server

    Dutta, Mitra

    1998-01-01

    This volume includes highlights of the theories and experimental findings that underlie essential phenomena occurring in quantum-based devices and systems as well as the principles of operation of selected novel quantum-based electronic devices and systems. A number of the emerging approaches to creating new types of quantum-based electronic devices and systems are also discussed.

  5. [Partial replacement of obsolete prosthetic implants].

    Science.gov (United States)

    Petit, R

    2005-10-01

    suit best the patient's health condition and try and avoid any hazard. Rejecting the option of partial replacement just because of parts unavailability is not acceptable when it seems the safest way to get the best result. Help can come from orthopedic surgeons themselves, if they give to their patient precise reports on the primary arthroplasty. The technical references of all the devices devoted to joint arthroplasty should not only be collected by public health services (AFSSAPS) but they should also be available to orthopedic surgeons. The real production cost of prosthetic elements should be taken into account in order to encourage the companies to deliver parts that are not on the market anymore. PMID:16327696

  6. Tunable thermal switching via DNA-based nano-devices

    International Nuclear Information System (INIS)

    DNA has a well-defined structural transition—the denaturation of its double-stranded form into two single strands—that strongly affects its thermal transport properties. We show that, according to a widely implemented model for DNA denaturation, one can engineer DNA ‘heattronic’ devices that have a rapidly increasing thermal conductance over a narrow temperature range across the denaturation transition (∼350 K). The origin of this rapid increase of conductance, or ‘switching’, is the softening of the lattice and suppression of nonlinear effects as the temperature crosses the transition temperature and DNA denatures. Most importantly, we demonstrate that DNA nano-junctions have a broad range of thermal tunability by varying the sequence and length, and exploiting the underlying nonlinear behavior. We discuss the role of disorder in the base sequence, as well as the relation to genomic DNA. These results set the basis for developing thermal devices out of materials with nonlinear structural dynamics, as well as understanding the underlying mechanisms of DNA denaturation. (paper)

  7. A Novel Gas Sensor Transducer Based on Phthalocyanine Heterojunction Devices

    Directory of Open Access Journals (Sweden)

    Marcel Bouvet

    2007-11-01

    Full Text Available Experimental data concerning the changes in the current-voltage (I-V perfor-mances of a molecular material-based heterojunction consisting of hexadecafluorinatednickel phthalocyanine (Ni(F16Pc and nickel phthalocyanine (NiPc,(Au|Ni(F16Pc|NiPc|Al are introduced as an unprecedented principle of transduction for gassensing performances. The respective n- and p-type doped-insulator behaviors of therespective materials are supported, owing to the observed changes in surface potential(using the Kelvin probe method after submission to electron donor (ammonia and electronacceptor gases (ozone. On the other hand, the bilayer device exhibits strong variations inthe built-in potential of the junction and in its rectification ratio. Moreover, large increasesoccur in forward and reverse currents in presence of ammonia vapors. These make possiblea multimodal principle of detection controlled by a combined effect between theheterojunction and the NiPc|Al contact. Indeed, this metal/organic junction plays a criticalrole regarding the steady asymmetry of the I-V profiles during the device’s doping evenusing high ammonia concentrations. This approach offers a more sophisticated alternative tothe classically studied, but at times rather operation-limited, resistive gas sensors.

  8. White electrophosphorescent devices based on tricolour emissive layers

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yu [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Hua Yulin [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Wu Xiaoming [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Zhang Guohui [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Hui Juanli [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Zhang Lijuan [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Liu Qian [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Ma Liang [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Yin Shougen [Institute of Physical Materials, Tianjin University of Technology, Tianjin, 300384 (China); Petty, M C [School of Engineering, University of Durham, Durham DH1 3LE (United Kingdom)

    2008-01-21

    We demonstrate high efficiency, white organic light-emitting devices based on a structure using multiple emissive layers and fabricated without a hole-injecting layer. 2,5,8,11-tetra-tertbutylperylene (TBPe) was used as the blue fluorescent layer and the overall device configuration was indium tin oxide (ITO)/N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-benzidine (NPB)/4,4'-N, N'-dicarbazole-biphenyl (CBP): bis[1-(phenyl)isoquinoline] iridium (III) acetylanetonate [Ir(piq){sub 2}(acac)]/CBP:fac-tris(2-phenylpyridine) iridium [Ir(ppy){sub 3}]/CBP: TBPe/2, 9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)/(8-hydroxyquinoline) aluminium (Alq{sub 3})/LiF/Al. This structure possessed a maximum luminous efficiency of 14.2 cd A{sup -1} at a current density of 4 mA cm{sup -2} and a maximum brightness of 40 520 cd m{sup -2} at 25 V. The Commission Internationale de L'Eclairage coordinates changed only from (0.27, 0.38) to (0.33, 0.38), with the brightness varying from 100 to 25 640 cd m{sup -2}, as the applied voltage was increased from 10 to 23 V.

  9. A Game-theoretic Framework for Network Coding Based Device-to-Device Communications

    KAUST Repository

    Douik, Ahmed

    2016-06-29

    This paper investigates the delay minimization problem for instantly decodable network coding (IDNC) based deviceto- device (D2D) communications. In D2D enabled systems, users cooperate to recover all their missing packets. The paper proposes a game theoretic framework as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. The session is modeled by self-interested players in a non-cooperative potential game. The utility functions are designed so as increasing individual payoff results in a collective behavior achieving both a desirable system performance in a shared network environment and the Nash equilibrium. Three games are developed whose first reduces the completion time, the second the maximum decoding delay and the third the sum decoding delay. The paper, further, improves the formulations by including a punishment policy upon collision occurrence so as to achieve the Nash bargaining solution. Learning algorithms are proposed for systems with complete and incomplete information, and for the imperfect feedback scenario. Numerical results suggest that the proposed game-theoretical formulation provides appreciable performance gain against the conventional point-to-multipoint (PMP), especially for reliable user-to-user channels.

  10. Preliminary MRI study on hemodynamics after prosthetic cardiac valve implantation

    International Nuclear Information System (INIS)

    Objective: To assess the function of prosthetic valve by magnetic resonance imaging (MRI), and to measure the blood velocity downstream of prosthetic valve and three-dimensional surface profiles so as to provide the original materials for appearance and development of thrombi-embolic complications in the long time follow-up. Methods: Twenty-seven cases with prosthetic aortic valve were examined and the blood velocity was measured by using MRI. The diseased heart valves were replaced with two prosthetic valves in 20 cases, and replaced with single prosthetic valve in 7 cases. The axial velocity components were measured at three positions near the valve including half, one, and two diameter downstream in the ascending aorta. Two and three-dimensional surface profile reconstruction were analyzed by using flow analysis software and Matlab 6.5 software. Results: In 16 cases with prosthetic aortic valve replacement with two leaflets prosthetic valves, the velocity profiles downstream of the valve prosthetic reflecting the valve design was nearly three velocity, jets of the two major orifices and the central slit between the two leaflets. In 4 cases with prosthetic aortic valve replace with Sorin two leaflets prosthetic valve, the velocity profiles downstream was nearly two velocity jets of the two major orifices. In 20 cases replaced with two leaflets prosthetic valves, blood velocity profiles were skewed with highest velocities. Seven cases with single leaflet showed single velocity jets of the major orifices at peak systole. Retrograde velocities occurred in part of the lateral orifice regions in 26 cases. Three-dimensional surface profiles downstream of the prosthetic aortic valve reflected the valve design. The blood velocity profiles with prosthetic aortic valve in the one diameter downstream in the ascending aorta clearly showed the valve design. Conclusion: MRI is a non-invasive, direct, and in-vivo method of choice to assess the valvular function and is the

  11. The radiology of prosthetic heart valves

    International Nuclear Information System (INIS)

    The development of prosthetic heart valves in the late 1950s ushered in a new era in the treatment of heart disease. The radiologist has an important role to play preoperatively in the diagnosis of valvular heart disease. Radiology is valuable in identification of the implanted prosthetic valve and recognition of complications associated with valve implantation. Radiologists must be familiar with the imaging techniques best suited to evaluate the function of the valve prosthesis in question. In this chapter the authors discuss the radiographic approach to the evaluation of the status of patients for valve replacement and the imaging problems peculiar to the types of valves in current use. The relative value of plain-film radiography, fluoroscopy, videorecording and cinerecording, and aortography is addressed, as well as the potential value of magnetic resonance imaging and subsecond dynamic computed tomography

  12. Common Prosthetic Implant Complications in Fixed Restorations.

    Science.gov (United States)

    Link-Bindo, Elyce E; Soltys, James; Donatelli, David; Cavanaugh, Richard

    2016-07-01

    Many clinicians consider implants to be one of the most important innovations in dental care. Even so, over the past 40 years of implant dentistry, complications have been a constant struggle for restorative dentists, surgeons, and patients alike. Implant-related problems can be particularly challenging and frustrating, especially given that an implant is thought to be a "lifetime" solution expected to yield minimal difficulties. This, however, is not necessarily the case with prosthetic restorations. With innovations in implant technology continuing to rapidly advance, maintaining knowledge of all the latest developments can be challenging for clinicians. The purpose of this article is to provide a basic understanding of the treatment, management, and prevention of common prosthetic and technical implant complications seen in the office of a restorative dentist. PMID:27548395

  13. Random laser action from flexible biocellulose-based device

    Science.gov (United States)

    dos Santos, Molíria V.; Dominguez, Christian T.; Schiavon, João V.; Barud, Hernane S.; de Melo, Luciana S. A.; Ribeiro, Sidney J. L.; Gomes, Anderson S. L.; de Araújo, Cid B.

    2014-02-01

    We demonstrate random lasing action in flexible bacterial cellulose (BC) membrane containing a laser-dye and either dielectric or metallic nanoparticles (NPs). The novel random laser system consists of BC nanofibers attached with Rhodamine 6G molecules and having incorporated either silica or silver NPs. The laser action was obtained by excitation of the samples with a 6 ns pulsed laser at 532 nm. Minimum laser threshold of ≈0.7 mJ/pulse was measured for the samples with silica NPs, whereas a laser threshold of 2.5 mJ/pulse for a system based on silver NPs was obtained. In both cases a linewidth narrowing from ≈50 to ≈4 nm was observed. Potential applications in biophotonics and life sciences are discussed for this proof-of-concept device.

  14. ISSUES IN IMPLEMENTING MARKER BASED TRACKING ON MASS MOBILE DEVICES

    Directory of Open Access Journals (Sweden)

    Kravtsov A. A.

    2015-11-01

    Full Text Available Tracking is a vast field of research associated with navigation, robotics, and virtual environments (virtual reality. Tracking for augmented reality requires higher level of precision, increased range of action, as well as work with a wider variety of input data. It is important that augmented reality technology requires tracking in real time, which also complicates the task. Correct visualization of objects in three-dimensional space requires six degrees of freedom tracking: three position values (x, y, z and three angles (rotation around the respective axes to determine the orientation. To solve this problem, different approaches and sensor types are being used. In this article, we present a brief history of the development of tracking technology and analyze the current approaches to implement the process of tracking on mass mobile devices such as smartphones and tablet computers. We also describe some issues in implementing optical marker based tracking for visualization of large scale models

  15. Nanoscale strain engineering of graphene and graphene-based devices

    Institute of Scientific and Technical Information of China (English)

    N-C Yeh; C-C Hsu; M L Teague; J-Q Wang; D A Boyd; C-C Chen

    2016-01-01

    Structural distortions in nano-materials can induce dramatic changes in their electronic properties. This situation is well manifested in graphene, a two-dimensional honeycomb structure of carbon atoms with only one atomic layer thickness. In particular, strained graphene can result in both charging effects and pseudo-magnetic fields, so that controlled strain on a perfect graphene lattice can be tailored to yield desirable electronic properties. Here, we describe the theoretical foundation for strain-engineering of the electronic properties of graphene, and then provide experimental evidence for strain-induced pseudo-magnetic fields and charging effects in monolayer graphene. We further demonstrate the feasibility of nano-scale strain engineering for graphene-based devices by means of theoretical simula-tions and nano-fabrication technology.

  16. Nanoscale strain engineering of graphene and graphene-based devices

    Science.gov (United States)

    Yeh, N.-C.; Hsu, C.-C.; Teague, M. L.; Wang, J.-Q.; Boyd, D. A.; Chen, C.-C.

    2016-06-01

    Structural distortions in nano-materials can induce dramatic changes in their electronic properties. This situation is well manifested in graphene, a two-dimensional honeycomb structure of carbon atoms with only one atomic layer thickness. In particular, strained graphene can result in both charging effects and pseudo-magnetic fields, so that controlled strain on a perfect graphene lattice can be tailored to yield desirable electronic properties. Here, we describe the theoretical foundation for strain-engineering of the electronic properties of graphene, and then provide experimental evidence for strain-induced pseudo-magnetic fields and charging effects in monolayer graphene. We further demonstrate the feasibility of nano-scale strain engineering for graphene-based devices by means of theoretical simulations and nano-fabrication technology.

  17. Rapid prototyping technologies in prosthetic dentistry

    OpenAIRE

    YILDIRIM, Arş. Gör. Dt. Melike Pınar; BAYINDIR, Prof. Dr. Funda

    2013-01-01

    Emerged as the concept of rapid prototyping technology, nowadays, is seen as the future of quick and direct production. This technology found applications with metal framework of fixed partial dentures, framework of removable partial dentures, facial protheses and titanium implants in prosthetic dentistry. The virtual image of the restoration is tranferred to the computer and the laser beam is sintered the selected areas on the alloy powders and the restoration is produced layer by layer at s...

  18. Prosthetic management of an ocular defect

    Directory of Open Access Journals (Sweden)

    Siddesh Kumar Chintal

    2010-01-01

    Full Text Available The disfigurement associated with the loss of an eye can cause significant physical and emotional problems. Various treatment modalities are available, one of which is implants. Although implant has a superior outcome, it may not be advisable in all patients due to economic factors. The present article describes the prosthetic management of an ocular defect with a custom-made ocular prosthesis.

  19. Molecular-based electronically switchable tunnel junction devices.

    Science.gov (United States)

    Collier, C P; Jeppesen, J O; Luo, Y; Perkins, J; Wong, E W; Heath, J R; Stoddart, J F

    2001-12-19

    Solid-state tunnel junction devices were fabricated from Langmuir Blodgett molecular monolayers of a bistable [2]catenane, a bistable [2]pseudorotaxane, and a single-station [2]rotaxane. All devices exhibited a (noncapacitive) hysteretic current-voltage response that switched the device between high- and low-conductivity states, although control devices exhibited no such response. Correlations between the structure and solution-phase dynamics of the molecular and supramolecular systems, the crystallographic domain structure of the monolayer film, and the room-temperature device performance characteristics are reported. PMID:11741428

  20. New Evolving Directions for Device Performance Optimization Based Integration of Compound Semiconductor Devices on Silicon

    Directory of Open Access Journals (Sweden)

    Partha Mukhopadhyay

    2011-01-01

    Full Text Available Rapid advances in Compound Semiconductor (CS technologies over last several decades have lead to high performances in peak power, power added efficiency (PAE and linearity, but these devices are not amenable for integration on mainstream silicon technologies. A strategic direction has been presented for the growth of CS devices on silicon with challenges abounding in scalability, compatibility and cost effectiveness while extracting optimized device performances. The approach at IIT Kharagpur has been simulation and experimental development of customized metamorphic buffers that are scalable and compatible to silicon without sacrificing any CS performances, primarily for electronic applications. This has evolved into a new strategic paradigm for performance optimization of seemingly competing and disparate properties which otherwise will not be supported by conventional process technologies. Simulation of these next generation structures reveals assimilation of superior device properties, with a novel five Indium content composite channel MHEMT indicating improvements over existing composite channel MHEMT in terms of linearity and higher current performances.

  1. Swarm Optimization-Based Magnetometer Calibration for Personal Handheld Devices

    Directory of Open Access Journals (Sweden)

    Naser El-Sheimy

    2012-09-01

    Full Text Available Inertial Navigation Systems (INS consist of accelerometers, gyroscopes and a processor that generates position and orientation solutions by integrating the specific forces and rotation rates. In addition to the accelerometers and gyroscopes, magnetometers can be used to derive the user heading based on Earth’s magnetic field. Unfortunately, the measurements of the magnetic field obtained with low cost sensors are usually corrupted by several errors, including manufacturing defects and external electro-magnetic fields. Consequently, proper calibration of the magnetometer is required to achieve high accuracy heading measurements. In this paper, a Particle Swarm Optimization (PSO-based calibration algorithm is presented to estimate the values of the bias and scale factor of low cost magnetometers. The main advantage of this technique is the use of the artificial intelligence which does not need any error modeling or awareness of the nonlinearity. Furthermore, the proposed algorithm can help in the development of Pedestrian Navigation Devices (PNDs when combined with inertial sensors and GPS/Wi-Fi for indoor navigation and Location Based Services (LBS applications.

  2. Graphene-Based Integrated Photovoltaic Energy Harvesting/Storage Device.

    Science.gov (United States)

    Chien, Chih-Tao; Hiralal, Pritesh; Wang, Di-Yan; Huang, I-Sheng; Chen, Chia-Chun; Chen, Chun-Wei; Amaratunga, Gehan A J

    2015-06-24

    Energy scavenging has become a fundamental part of ubiquitous sensor networks. Of all the scavenging technologies, solar has the highest power density available. However, the energy source is erratic. Integrating energy conversion and storage devices is a viable route to obtain self-powered electronic systems which have long-term maintenance-free operation. In this work, we demonstrate an integrated-power-sheet, consisting of a string of series connected organic photovoltaic cells (OPCs) and graphene supercapacitors on a single substrate, using graphene as a common platform. This results in lighter and more flexible power packs. Graphene is used in different forms and qualities for different functions. Chemical vapor deposition grown high quality graphene is used as a transparent conductor, while solution exfoliated graphene pastes are used as supercapacitor electrodes. Solution-based coating techniques are used to deposit the separate components onto a single substrate, making the process compatible with roll-to-roll manufacture. Eight series connected OPCs based on poly(3-hexylthiophene)(P3HT):phenyl-C61-butyric acid methyl ester (PC60 BM) bulk-heterojunction cells with aluminum electrodes, resulting in a ≈5 V open-circuit voltage, provide the energy harvesting capability. Supercapacitors based on graphene ink with ≈2.5 mF cm(-2) capacitance provide the energy storage capability. The integrated-power-sheet with photovoltaic (PV) energy harvesting and storage functions had a mass of 0.35 g plus the substrate. PMID:25703342

  3. 3D Printed Paper-Based Microfluidic Analytical Devices

    Directory of Open Access Journals (Sweden)

    Yong He

    2016-06-01

    Full Text Available As a pump-free and lightweight analytical tool, paper-based microfluidic analytical devices (μPADs attract more and more interest. If the flow speed of μPAD can be programmed, the analytical sequences could be designed and they will be more popular. This reports presents a novel μPAD, driven by the capillary force of cellulose powder, printed by a desktop three-dimensional (3D printer, which has some promising features, such as easy fabrication and programmable flow speed. First, a suitable size-scale substrate with open microchannels on its surface is printed. Next, the surface of the substrate is covered with a thin layer of polydimethylsiloxane (PDMS to seal the micro gap caused by 3D printing. Then, the microchannels are filled with a mixture of cellulose powder and deionized water in an appropriate proportion. After drying in an oven at 60 °C for 30 min, it is ready for use. As the different channel depths can be easily printed, which can be used to achieve the programmable capillary flow speed of cellulose powder in the microchannels. A series of microfluidic analytical experiments, including quantitative analysis of nitrite ion and fabrication of T-sensor were used to demonstrate its capability. As the desktop 3D printer (D3DP is very cheap and accessible, this device can be rapidly printed at the test field with a low cost and has a promising potential in the point-of-care (POC system or as a lightweight platform for analytical chemistry.

  4. Atom devices based on single dopants in silicon nanostructures

    Directory of Open Access Journals (Sweden)

    Jablonski Ryszard

    2011-01-01

    Full Text Available Abstract Silicon field-effect transistors have now reached gate lengths of only a few tens of nanometers, containing a countable number of dopants in the channel. Such technological trend brought us to a research stage on devices working with one or a few dopant atoms. In this work, we review our most recent studies on key atom devices with fundamental structures of silicon-on-insulator MOSFETs, such as single-dopant transistors, preliminary memory devices, single-electron turnstile devices and photonic devices, in which electron tunneling mediated by single dopant atoms is the essential transport mechanism. Furthermore, observation of individual dopant potential in the channel by Kelvin probe force microscopy is also presented. These results may pave the way for the development of a new device technology, i.e., single-dopant atom electronics.

  5. First realization of the piezoelectronic stress-based transduction device.

    Science.gov (United States)

    Chang, Josephine B; Miyazoe, Hiroyuki; Copel, Matthew; Solomon, Paul M; Liu, Xiao-Hu; Shaw, Thomas M; Schrott, Alejandro G; Gignac, Lynne M; Martyna, Glenn J; Newns, Dennis M

    2015-09-18

    We present the first realization of a monolithically integrated piezoelectronic transistor (PET), a new transduction-based computer switch which could potentially operate conventional computer logic at 1/50 the power requirements of current Si-based transistors (Chen 2014 Proc. IEEE ICICDT pp 1-4; Mamaluy et al 2014 Proc. IWCE pp 1-2). In PET operation, an input gate voltage expands a piezoelectric element (PE), transducing the input into a pressure pulse which compresses a piezoresistive element (PR). The PR resistance goes down, transducing the signal back to voltage and turning the switch 'on'. This transduction physics, in principle, allows fast, low-voltage operation. In this work, we address the processing challenges of integrating chemically incompatible PR and PE materials together within a surrounding cage against which the PR can be compressed. This proof-of-concept demonstration of a fully integrated, stand-alone PET device is a key step in the development path toward a fast, low-power very large scale integration technology. PMID:26302818

  6. Optimal alignment of mirror based pentaprisms for scanning deflectometric devices

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Geckeler, Ralf D.; Yashchuk, Valeriy V.; Gubarev, Mikhail V.; Buchheim, Jana; Siewert, Frank; Zeschke, Thomas

    2011-03-04

    In the recent work [Proc. of SPIE 7801, 7801-2/1-12 (2010), Opt. Eng. 50(5) (2011), in press], we have reported on improvement of the Developmental Long Trace Profiler (DLTP), a slope measuring profiler available at the Advanced Light Source Optical Metrology Laboratory, achieved by replacing the bulk pentaprism with a mirror based pentaprism (MBPP). An original experimental procedure for optimal mutual alignment of the MBPP mirrors has been suggested and verified with numerical ray tracing simulations. It has been experimentally shown that the optimally aligned MBPP allows the elimination of systematic errors introduced by inhomogeneity of the optical material and fabrication imperfections of the bulk pentaprism. In the present article, we provide the analytical derivation and verification of easily executed optimal alignment algorithms for two different designs of mirror based pentaprisms. We also provide an analytical description for the mechanism for reduction of the systematic errors introduced by a typical high quality bulk pentaprism. It is also shown that residual misalignments of an MBPP introduce entirely negligible systematic errors in surface slope measurements with scanning deflectometric devices.

  7. The role of osteoblasts in peri-prosthetic osteolysis.

    LENUS (Irish Health Repository)

    O'Neill, S C

    2013-08-01

    Peri-prosthetic osteolysis and subsequent aseptic loosening is the most common reason for revising total hip replacements. Wear particles originating from the prosthetic components interact with multiple cell types in the peri-prosthetic region resulting in an inflammatory process that ultimately leads to peri-prosthetic bone loss. These cells include macrophages, osteoclasts, osteoblasts and fibroblasts. The majority of research in peri-prosthetic osteolysis has concentrated on the role played by osteoclasts and macrophages. The purpose of this review is to assess the role of the osteoblast in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts and contribute to the osteolytic process by two mechanisms. First, particles and metallic ions have been shown to inhibit the osteoblast in terms of its ability to secrete mineralised bone matrix, by reducing calcium deposition, alkaline phosphatase activity and its ability to proliferate. Secondly, particles and metallic ions have been shown to stimulate osteoblasts to produce pro inflammatory mediators in vitro. In vivo, these mediators have the potential to attract pro-inflammatory cells to the peri-prosthetic area and stimulate osteoclasts to absorb bone. Further research is needed to fully define the role of the osteoblast in peri-prosthetic osteolysis and to explore its potential role as a therapeutic target in this condition.

  8. Biological effects of dynamic shear stress in cardiovascular pathologies and devices

    OpenAIRE

    Girdhar, Gaurav; Bluestein, Danny

    2008-01-01

    Altered and highly dynamic shear stress conditions have been implicated in endothelial dysfunction leading to cardiovascular disease, and in thromboembolic complications in prosthetic cardiovascular devices. In addition to vascular damage, the pathological flow patterns characterizing cardiovascular pathologies and blood flow in prosthetic devices induce shear activation and damage to blood constituents. Investigation of the specific and accentuated effects of such flow-induced perturbations ...

  9. Nonvolatile WORM memory devices based on polymethacrylate with azoanthraquinone group

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel polymethacrylate containing azoanthraquinone chromophore in the side chain(PMAzoaq6) was synthesized and characterized.An electronic memory device having the indium-tin oxide(ITO)/PMAzoaq6/Al sandwich structure was fabricated and its electrical bistability was investigated.The as-fabricated device was initially found to be at the OFF state and the switching threshold voltage was 1.5 V.After undergoing the OFF-to-ON transition,the device maintains the high conducting state(ON state) even after turning off the electrical power and applying a reverse bias.The device exhibits a write-once-read-many-times(WORM) memory effect with a high ON/OFF current ratio of up to 105 and a long retention time in both ON and OFF states,which demonstrated that the synthetic azoanthraquinone-containing polymer possesses a high potential to become polymeric memory devices.

  10. EMPLOYEE TRUST BASED INDUSTRIAL DEVICE DEPLOYMENT AND INITIAL KEY ESTABLISHMENT

    Directory of Open Access Journals (Sweden)

    Apala Ray

    2016-01-01

    Full Text Available An efficient key management system is required to support cryptography. Most key management systemsuse either pre-installed shared keys or install initial security parameters using out-of-band channels. These methods create an additional burden for engineers who manage the devices in industrial plants. Hence,device deployment in industrial plants becomes a challenging task in order to achieve security. In thiswork, we present a device deployment framework that can support key management using the existing trust towards employees in a plant. This approach reduces the access to initial security parameters by employees; rather it helps to bind the trust of the employee with device commissioning. Thus, this approach presents a unique solution to the device deployment problem. Further, through a proof-of-concept implementation and security analysis using the AVISPA tool, we present that our framework is feasible to implement and satisfies our security objectives.

  11. Carbon material based microelectromechanical system (MEMS): Fabrication and devices

    Science.gov (United States)

    Xu, Wenjun

    This PhD dissertation presents the exploration and development of two carbon materials, carbon nanotubes (CNTs) and carbon fiber (CF), as either key functional components or unconventional substrates for a variety of MEMS applications. Their performance in three different types of MEMS devices, namely, strain/stress sensors, vibration-powered generators and fiber solar cells, were evaluated and the working mechanisms of these two non-traditional materials in these systems were discussed. The work may potentially enable the development of new types of carbon-MEMS devices. Carbon nanotubes were selected from the carbon family due to several advantageous characteristics that this nanomaterial offers. They carry extremely high mechanical strength (Ey=1TPa), superior electrical properties (current density of 4x109 A/cm2), exceptional piezoresistivity (G=2900), and unique spatial format (high aspect ratio hollow nanocylinder), among other properties. If properly utilized, all these merits can give rise to a variety of new types of carbon nanotube based micro- and nanoelectronics that can greatly fulfill the need for the next generation of faster, smaller and better devices. However, before these functions can be fully realized, one substantial issue to cope with is how to implement CNTs into these systems in an effective and controllable fashion. Challenges associated with CNTs integration include very poor dispersibility in solvents, lack of melting/sublimation point, and unfavorable rheology with regard to mixing and processing highly viscous, CNT-loaded polymer solutions. These issues hinder the practical progress of CNTs both in a lab scale and in the industrial level. To this end, a MEMS-assisted electrophoretic deposition technique was developed, aiming to achieve controlled integration of CNT into both conventional and flexible microsystems at room temperature with a relatively high throughput. MEMS technology has demonstrated strong capability in developing

  12. NiCu-based superconducting devices: fabrication and characterization

    International Nuclear Information System (INIS)

    The critical Josephson current (IC) in superconducting/ferromagnetic (S/F) multilayer-based junctions can be controlled by changing the relative directions of the magnetization in the F-layers. Recent experimental works show that an enhancement of IC is achieved in S/F weak links when the alternating F-layers are antiparallel aligned. We present preliminary experimental results concerning the dependence of IC on the relative orientation of the ferromagnetic layers in S/F1/I/F2/S tunnel junctions where the F-layers are obtained by changing the relative composition of NiCu alloys. The multilayers were grown by electron beam deposition, and processed by Focused Ion Beam lithography. The magnetic state of the devices was directly determined by measuring the current perpendicular to plane (CPP) magnetoresistance (MR) at high bias. IC was found to be larger when the F-layers are antiparallel aligned. The maximum change of IC corresponds to the maximum change of MR. The application of a magnetic field induces a transition in the shape of the currentvoltage curve that seems to suggest Coulomb blockade effect

  13. NiCu-based superconducting devices: fabrication and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Ruotolo, A [Universita di Napoli Federico II, Dip. Scienze Fisiche, Facolta d' Ingegneria, P.le Tecchio 80, 80125 Naples (Italy); Pullini, D [Centro Ricerche FIAT, Strada Torino 50, 10043 Orbassano, Turin (Italy); Adamo, C [Universita di Salerno, Dip. Scienze Fisiche, Via S. Allende 1, 84081 Baronissi, Salerno (Italy); Pepe, G P [Universita di Napoli Federico II, Dip. Scienze Fisiche, Facolta d' Ingegneria, P.le Tecchio 80, 80125 Naples (Italy); Maritato, L [Universita di Salerno, Dip. Scienze Fisiche, Via S. Allende 1, 84081 Baronissi, Salerno (Italy); Innocenti, G [Centro Ricerche FIAT, Strada Torino 50, 10043 Orbassano, Turin (Italy); Perlo, P [Centro Ricerche FIAT, Strada Torino 50, 10043 Orbassano, Turin (Italy)

    2006-06-01

    The critical Josephson current (I{sub C}) in superconducting/ferromagnetic (S/F) multilayer-based junctions can be controlled by changing the relative directions of the magnetization in the F-layers. Recent experimental works show that an enhancement of I{sub C} is achieved in S/F weak links when the alternating F-layers are antiparallel aligned. We present preliminary experimental results concerning the dependence of I{sub C} on the relative orientation of the ferromagnetic layers in S/F{sub 1}/I/F{sub 2}/S tunnel junctions where the F-layers are obtained by changing the relative composition of NiCu alloys. The multilayers were grown by electron beam deposition, and processed by Focused Ion Beam lithography. The magnetic state of the devices was directly determined by measuring the current perpendicular to plane (CPP) magnetoresistance (MR) at high bias. I{sub C} was found to be larger when the F-layers are antiparallel aligned. The maximum change of I{sub C} corresponds to the maximum change of MR. The application of a magnetic field induces a transition in the shape of the currentvoltage curve that seems to suggest Coulomb blockade effect.

  14. Electron-doping of graphene-based devices by hydrazine

    International Nuclear Information System (INIS)

    A facile and effective technique to tune the electronic properties of graphene is essential to facilitate the flexibility of graphene-based device performances. Here, the use of hydrazine as a solution-processable and effective n-type dopant for graphene is described. By dropping hydrazine solutions at different concentrations on a graphene surface, the Dirac point of graphene can be remarkably tuned. The transport behavior of graphene can be changed from p-type to n-type accordingly, demonstrating the controllable and adjustable doping effect of the hydrazine solutions. Accompanying the Dirac point shift is an enhanced hysteretic behavior of the graphene conductance, indicating an increasing trap state density induced by the hydrazine adsorbates. The electron-doping of graphene by the hydrazine solutions can be additionally confirmed with graphene/p-type silicon heterojunctions. The decrease of the junction current after the hydrazine treatment demonstrates an increase of the junction barrier between graphene and silicon, which is essentially due to the electron-doping of graphene and the resultant upshift of the Fermi level. Finally, partially doped graphene is realized and its electrical property is studied to demonstrate the potential of the hydrazine solutions to selectively electron-doping graphene for future electronic applications

  15. Performance Optimization based Spectrum Analysis on OFRA and EDFA Devices

    Directory of Open Access Journals (Sweden)

    Liu Liying

    2013-07-01

    Full Text Available As the key devices, erbium doped fiber amplifier (EDFA and optical Raman fiber amplifier (OFRA have been widely applied in the fields of optical communication, sensing and measurement. However, the performance optimization is always one of the hot topics in the study of optical fiber amplifiers, because its output characteristics are hardly dependent to the key designing parameters. In this paper, in order to cope with such problem, we adopt the novel analysis based spectrum to study the output performance of EDFA and OFRA systems, respectively. Through simulating the operation of the two amplifying system, their output characteristics are first demonstrated with the various parameters. And according to the numerical results obtained, the key designing parameters of EDFA and OFRA systems are determinate, and the performance of amplifying systems are improved and optimized obviously in terms of output power, signal noise ratio, and the level of gain flatness.   Keywords: Fiber Raman Amplifier, Erbium Doped Fiber Amplifier, Performance optimization, Spectrum analysis, Simulation.  

  16. Efficient light emitting devices based on phosphorescent partially doped emissive layers

    KAUST Repository

    Yang, Xiaohui

    2013-05-29

    We report efficient organic light emitting devices employing an ultrathin phosphor emissive layer. The electroluminescent spectra of these devices can be tuned by introducing a low-energy emitting phosphor layer into the emission zone. Devices with the emissive layer consisting of multiple platinum-complex/spacer layer cells show a peak external quantum efficiency of 18.1%, which is among the best EQE values for platinum-complex based light emitting devices. Devices with an ultrathin phosphor emissive layer show stronger luminance decay with the operating time compared to the counterpart devices having a host-guest emissive layer.

  17. Magnet-based Around Device Interaction for Playful Music Composition and Gaming

    NARCIS (Netherlands)

    A. El Ali; H. Ketabdar

    2013-01-01

    Around Device Interaction (ADI) has expanded the interaction space on mobile devices to allow 3D gesture interaction around the device. In this paper, the authors look specifically at magnet-based ADI and its applied use in a playful, music-related context. Using three musical applications developed

  18. [Panorama of prosthetic options in osseointegrated implantology].

    Science.gov (United States)

    Khayat, P; Missika, P; Hockers, T

    1990-12-01

    Today, several prosthetic options can be used with osseointegrated implants. Fixed bridges may be retained by screws or cemented. Detachable bridges may be screwed on cylindrical, conical, straight or angulated abutments. In certain cases, they will be placed directly in contact with the implants. Cemented bridges may be placed over screwed, cemented or transfixed copings. They also may be cemented over transfixed metallic structures already splinting the implants. Removable prosthesis may be stabilized with bars, stud attachments or magnets. All these different options are discussed, and their advantages and disadvantages presented. PMID:2268784

  19. Graphene Electronic Device Based Biosensors and Chemical Sensors

    Science.gov (United States)

    Jiang, Shan

    Two-dimensional layered materials, such as graphene and MoS2, are emerging as an exciting material system for a new generation of atomically thin electronic devices. With their ultrahigh surface to volume ratio and excellent electrical properties, 2D-layered materials hold the promise for the construction of a generation of chemical and biological sensors with unprecedented sensitivity. In my PhD thesis, I mainly focus on graphene based electronic biosensors and chemical sensors. In the first part of my thesis, I demonstrated the fabrication of graphene nanomesh (GNM), which is a graphene thin film with a periodic array of holes punctuated in it. The periodic holes introduce long periphery active edges that provide a high density of functional groups (e.g. carboxylic groups) to allow for covalent grafting of specific receptor molecules for chemical and biosensor applications. After covalently functionalizing the GNM with glucose oxidase, I managed to make a novel electronic sensor which can detect glucose as well as pH change. In the following part of my thesis I demonstrate the fabrication of graphene-hemin conjugate for nitric oxide detection. The non-covalent functionalization through pi-pi stacking interaction allows reliable immobilization of hemin molecules on graphene without damaging the graphene lattice to ensure the highly sensitive and specific detection of nitric oxide. The graphene-hemin nitric oxide sensor is capable of real-time monitoring of nitric oxide concentrations, which is of central importance for probing the diverse roles of nitric oxide in neurotransmission, cardiovascular systems, and immune responses. Our studies demonstrate that the graphene-hemin sensors can respond rapidly to nitric oxide in physiological environments with sub-nanomolar sensitivity. Furthermore, in vitro studies show that the graphene-hemin sensors can be used for the detection of nitric oxide released from macrophage cells and endothelial cells, demonstrating their

  20. Development of Home-Based Frailty Detection Device Using Wireless Sensor Networks

    OpenAIRE

    Lin, Chung-Chih; Chen, Chun-Chang; Lin, Pay-Shin; Lee, Ren-Guey; Huang, Jing-Siang; Tsai, Tsai-Hsuan; Chang, Yu-Chuan

    2016-01-01

    This study develops a home-based frailty detection device that uses embedded systems and wireless sensing technology. This system helps monitor the impact of aging among the elderly through wireless automatic detection. The detection system consists of four devices. The first device, called eScale, simulates the traditional falling ruler test to measure reaction time. Another device, called eChair, measures the pressure exerted by a test subject through a pressure sensor. It is used to test t...

  1. A Rhythm-Based Authentication Scheme for Smart Media Devices

    OpenAIRE

    Jae Dong Lee; Young-Sik Jeong; Jong Hyuk Park

    2014-01-01

    In recent years, ubiquitous computing has been rapidly emerged in our lives and extensive studies have been conducted in a variety of areas related to smart devices, such as tablets, smartphones, smart TVs, smart refrigerators, and smart media devices, as a measure for realizing the ubiquitous computing. In particular, smartphones have significantly evolved from the traditional feature phones. Increasingly higher-end smartphone models that can perform a range of functions are now available. S...

  2. Detergents sensing system based on SH-SAW devices

    OpenAIRE

    Vivancos, José-Luís; Rácz, Z.; Cole, M; Soto Camino, Juan; Gardner, J. W.

    2011-01-01

    We report on the design and characterization of a novel analytical sensing system for the detection and discrimination of various detergents. Our sensor system could play a key role in the development of more efficient and environmentally-friendly washing machines by enabling the measurement of residual detergents. The sensing device comprises of a dual shear horizontal surface acoustic wave (SH-SAW) resonator device housed in a poly- dimethylsiloxane (PDMS) microfluidic chamber. Unmetalized ...

  3. Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices

    OpenAIRE

    Dermot Diamond; Martina O’Toole

    2008-01-01

    The ever increasing demand for in situ monitoring of health, environment and security has created a need for reliable, miniaturised sensing devices. To achieve this, appropriate analytical devices are required that possess operating characteristics of reliability, low power consumption, low cost, autonomous operation capability and compatibility with wireless communications systems. The use of light emitting diodes (LEDs) as light sources is one strategy, which has been successfully applied i...

  4. Miniature gas sensing device based on near-infrared spectroscopy

    OpenAIRE

    Alfeeli, Bassam

    2005-01-01

    The identification and quantification of atoms, molecules, or ions concentrations in gaseous samples are in great demand for medical, environmental, industrial, law enforcement and national security applications. These applications require in situ, high-resolution, non-destructive, sensitive, miniature, inexpensive, rapid detection, remotely accessed, real time and continuously operating chemical sensing devices. The aim of this work is to design a miniature optical sensing device that is cap...

  5. Effective Surface Conductivity Approach for Graphene Metamaterials Based Terahertz Devices

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Pizzocchero, Filippo; Booth, Tim; Bøggild, Peter; Lavrinenko, Andrei

    2013-01-01

    We propose a description of graphene metamaterials properties through the effective surface conductivity. On the example of tunable absorber we demonstrate that this approach allows for fast and efficient design of functional terahertz devices.......We propose a description of graphene metamaterials properties through the effective surface conductivity. On the example of tunable absorber we demonstrate that this approach allows for fast and efficient design of functional terahertz devices....

  6. Quantum transport in nanowire-based hybrid devices

    Energy Technology Data Exchange (ETDEWEB)

    Guenel, Haci Yusuf

    2013-05-08

    the Andreev reflection of quasiparticles at single interface, by suppressing the superconductivity of Al with small magnetic fields, as well as at double interface for zero magnetic field. The junction geometry was further changed by replacing the InAs nanowire with the InAs tube. In this case the GaAs/InAs core/shell tubular nanowires were contacted by two superconducting Nb electrodes. For this junction geometry we have demonstrated the interference of phase conjugated electron-hole pairs in the presence of coaxial magnetic. The effect of temperature, constant dc bias current and gate voltage on the magnetoresistance oscillations were examined. In the last part of this thesis, we have fabricated and characterized the single crystal Au nanowire-based proximity superconducting quantum interference device (SQUID).

  7. II-VI Materials-Based High Performance Intersubband Devices

    Science.gov (United States)

    Ravikumar, Arvind Pawan

    achieve normal-incident absorption, taking advantage of light-scattering in sloped surfaces; this method is wavelength independent and does not involve complicated fabrication techniques. With the performance of II-VI devices matching or surpassing existing commercial solutions, integrated mid-IR photonics based sensing is poised to play a big role in the future of sensing technologies.

  8. Prosthetic Rehabilitation in Children: An Alternative Clinical Technique

    Directory of Open Access Journals (Sweden)

    Nádia Carolina Teixeira Marques

    2013-01-01

    Full Text Available Complete and partial removable dentures have been used successfully in numerous patients with oligodontia and/or anodontia. However, there is little information in the literature regarding the principles and guidelines to prosthetic rehabilitation for growing children. This case report describes the management of a young child with oligodontia as well as the treatment planning and the prosthetic rehabilitation technique.

  9. Stiffness and hysteresis properties of some prosthetic feet

    NARCIS (Netherlands)

    Jaarsveld, van H.W.L.; Grootenboer, H.J.; Vries, de J.; Koopman, H.F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hyst

  10. Carbonitride based phosphors and light emitting devices using the same

    Science.gov (United States)

    Li, Yuanqiang; Tian, Yongchi; Romanelli, Michael Dennis

    2013-08-20

    Disclosed herein is a novel group of carbidonitride phosphors and light emitting devices which utilize these phosphors. In certain embodiments, the present invention is directed to a novel family of carbidonitride-based phosphors expressed as follows: Ca.sub.1-xAl.sub.x-xySi.sub.1-x+xyN.sub.2-x-xyC.sub.xy:A; (1) Ca.sub.1-x-zNa.sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xyC.sub.xy:- A; (2) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x- -xyC.sub.xy:A; (3) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xy-2w/- 3C.sub.xyO.sub.w-v/2H.sub.v:A; and (4) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xy-2w/- 3-v/3C.sub.xyO.sub.wH.sub.v:A, (4a) wherein 0xy+z, and 0

  11. Influence of rectification procedure on the counter-torque force of prosthetic screws of implant-retained frameworks

    Directory of Open Access Journals (Sweden)

    Mauro Antonio de Arruda Nobilo

    2008-01-01

    Full Text Available Objective: To evaluate the counter-force of prosthetic screws before and after the rectification procedure of the seating base of prosthetic framework screws. Methods: With a metal matrix containing three replicas of conical abutments (Micro-Unit; Conexão placed at 10 mm from center to center, ten multiple cast structures were made of a titanium monoblock. The multiple cast structures were fastened onto the metal matrix abutments with a torque of 10 NCm. The screwing sequence was performed from the central pillar towards the distal ones. The force (Ncmnecessary for counter-torque was evaluated using a digital torque meter (TQ3000; Lutron, Taipei, Taiwan. This procedure was carried out before and after rectification of the seating base of the prosthetic screws, by means of a manual rectifier tip (Conexão Sistemas de Prótese, São Paulo, Brazil. The mean counter-torque values were calculated for each structure before and after rectification. The t-Test for paired samples was used to compare the evaluated situations. Results: Significant difference was observed between the mean counter-torque force value of the prosthetic screws before (5.78±1.03Ncm and after (7.06±0.62Ncm the rectification procedures (p<0.01. Conclusion: The rectifying process of the seating base significantly increased the values of force required to counter-torque the prosthetic screws of cast implant-retained multiple frameworks.

  12. Graphene base heterojunction transistor: An explorative study on device potential, optimization, and base parasitics

    Science.gov (United States)

    Di Lecce, Valerio; Grassi, Roberto; Gnudi, Antonio; Gnani, Elena; Reggiani, Susanna; Baccarani, Giorgio

    2015-12-01

    The Graphene-Base Heterojunction Transistor (GBHT) is a novel device concept with a high potential for analog high-frequency RF operation, in which the current is due to both thermionic emission and tunneling. In this paper we study through numerical simulations the influence of previously uninvestigated aspects of Si- and Ge-based GBHTs-namely, crystallographic orientation and doping density values-on the device performance; a comparison with an aggressively scaled HBT structure is then reported. The simulations are carried out with an in-house developed code based on a 1-D quantum transport model within the effective mass approximation and the assumptions of ballistic transport with non-parabolic corrections and ideal semiconductor-graphene interface. We show that crystallographic orientation has a negligible effect on the GBHT performance. The doping density values in the GBHT emitter and collector regions can be tailored to maximize the device performance: the Si device shows better overall performance than the Ge one, yielding a peak cut-off frequency fT higher than 4 THz together with an intrinsic voltage gain above 10, or even higher fT at the cost of a lower gain. The Si-based GBHT can potentially outperform the SiGe HBT by a 2.8 higher fT . For a Si-based GBHT with a circular active region of diameter 50-100 nm, a theoretical balanced value for fT and fmax above 2 THz can be achieved, provided the base parasitics are carefully minimized.

  13. Simulated prosthetic vision: improving text accessibility with retinal prostheses.

    Science.gov (United States)

    Denis, Gregoire; Jouffrais, Christophe; Mailhes, Corinne; Mace, Marc J-M

    2014-01-01

    Image processing can improve significantly the every-day life of blind people wearing current and upcoming retinal prostheses relying on an external camera. We propose to use a real-time text localization algorithm to improve text accessibility. An augmented text-specific rendering based on automatic text localization has been developed. It has been evaluated in comparison to the classical rendering through a Simulated Prosthetic Vision (SPV) experiment with 16 subjects. Subjects were able to detect text in natural scenes much faster and further with the augmented rendering compared to the control rendering. Our results show that current and next generation of low resolution retinal prostheses may benefit from real-time text detection algorithms. PMID:25570307

  14. Flexible organic photovoltaic devices based on oligothiophene derivatives

    Institute of Scientific and Technical Information of China (English)

    Ping Liu; Tu Hua Chen; Wan Zhang Pan; Ming Sheng Huang; Wen Ji Deng; Yu Liang Mai; An Bo Luan

    2008-01-01

    For the purpose of developing flexible organic photovoltaic devices,we have fabricated two flexible devices using 5-formyl-2,2':5',2":5",2"'-quaterthiophene (4T-CHO),5-formyl-2,2':5',2":5",2'":5"',2"''-quinquethiophene (5T-CHO)and 3,4,9,10-peryle-netertracarboxylic dianhydride(PTCDA).The PET-ITO/4T-CHO/PTCDA/AI device has an open circuit voltage (V∝)of 1.56 V,photoelectric conversion efficiency of 0.77%.The PET-ITO/ST-CHO/PTCDA/AI device has a V∝ of 1.70 V,photoelectric conversion efficiency of 0.84%.The two flexible devices have high V∝(1.56 and 1.70 V).It is possible that intermolecular hydrogen bonding between-CHO group of nT-CHO and carboxylic dianhydride of PTCDA contributes to enhancing the efficiency by promoting interfacial electron transfer and eliminating the subconducting band trap sites.

  15. Prosthetic finger phalanges with lifelike skin compliance for low-force social touching interactions

    Directory of Open Access Journals (Sweden)

    Ge Shuzhi

    2011-03-01

    Full Text Available Abstract Background Prosthetic arms and hands that can be controlled by the user's electromyography (EMG signals are emerging. Eventually, these advanced prosthetic devices will be expected to touch and be touched by other people. As realistic as they may look, the currently available prosthetic hands have physical properties that are still far from the characteristics of human skins because they are much stiffer. In this paper, different configurations of synthetic finger phalanges have been investigated for their skin compliance behaviour and have been compared with the phalanges of the human fingers and a phalanx from a commercially available prosthetic hand. Methods Handshake tests were performed to identify which areas on the human hand experience high contact forces. After these areas were determined, experiments were done on selected areas using an indenting probe to obtain the force-displacement curves. Finite element simulations were used to compare the force-displacement results of the synthetic finger phalanx designs with that of the experimental results from the human and prosthetic finger phalanges. The simulation models were used to investigate the effects of (a varying the internal topology of the finger phalanx and (b varying different materials for the internal and external layers. Results and Conclusions During handshake, the high magnitudes of contact forces were observed at the areas where the full grasping enclosure of the other person's hand can be achieved. From these areas, the middle phalanges of the (a little, (b ring, and (c middle fingers were selected. The indentation experiments on these areas showed that a 2 N force corresponds to skin tissue displacements of more than 2 mm. The results from the simulation model show that introducing an open pocket with 2 mm height on the internal structure of synthetic finger phalanges increased the skin compliance of the silicone material to 235% and the polyurethane material to

  16. A novel thermal acoustic device based on porous graphene

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Lu-Qi; Liu, Ying; Ju, Zhen-Yi; Xie, Qian-Yi; Yang, Yi; Ren, Tian-Ling, E-mail: RenTL@tsinghua.edu.cn [Institute of Microelectronics, Tsinghua University, Beijing 10084 (China); Tsinghua National Laboratory for Information Science and Technology (TNList), Tsinghua University, Beijing 100084 (China); Tian, He [Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 (United States)

    2016-01-15

    A thermal acoustic (TA) device was fabricated by laser scribing technology. Polyimide (PI) can be converted into patterned porous graphene (PG) by laser’s irradiation in one step. The sound pressure level (SPL) of such TA device is related to laser power. The theoretical model of TA effect was established to analyze the relationship between the SPL and laser power. The theoretical results are in good agreement with experiment results. It was found that PG has a flat frequency response in the range of 5-20 kHz. This novel TA device has the advantages of one-step procedure, high flexibility, no mechanical vibration, low cost and so on. It can open wide applications in speakers, multimedia, medical, earphones, consumer electronics and many other aspects.

  17. Vibration energy harvesting with aluminum nitride-based piezoelectric devices

    International Nuclear Information System (INIS)

    This paper describes the measurement results of piezoelectric energy harvesters with aluminum nitride (AlN) as a piezoelectric material. AlN was chosen for its material properties and for its well-known sputter deposition process. For AlN devices a high optimum load resistance is required, which is favorable due to the high resulting voltage level. The output power harvested from mechanical vibrations has been measured on micromachined harvesters with different geometries. The resonance frequencies ranged from 200 up to 1200 Hz. The packaged devices had limited output powers and quality factors due to air damping caused by the package. A maximum output power of 60 µW has been measured on an unpackaged device at an acceleration of 2.0 g and at a resonance frequency of 572 Hz. The package of the harvester requires special attention, since air damping can significantly decrease the maximum power output

  18. Photoresponsive memory device based on Graphene/Boron Nitride heterostructure

    Science.gov (United States)

    Kahn, Salman; Velasco, Jairo, Jr.; Ju, Long; Wong, Dillon; Lee, Juwon; Tsai, Hsin Zon; Taniguchi, Takashi; Watanabe, Kenji; Zettl, Alex; Wang, Feng; Crommie, Michael

    2015-03-01

    Recent technological advancements have allowed the stacking of two dimensional layered material in order to create van der Waals heterostructures (VDH), enabling the design of novel properties by exploiting the proximal interaction between layers with different electronic properties. We report the creation of an optoelectronic memory device using a Graphene/Boron Nitride (hBN) heterostructure. Using the photo-induced doping phenomenon, we are able to spatially ``write'' a doping profile on graphene and ``read'' the profile through electrical transport and local probe techniques. We then utilize defect engineering to enhance the optoelectronic response of graphene and explore the effect of defects in hBN. Our work introduces a simple device architecture to create an optoelectronic memory device and contributes towards understanding the proximal effects of hBN on Graphene.

  19. A novel thermal acoustic device based on porous graphene

    International Nuclear Information System (INIS)

    A thermal acoustic (TA) device was fabricated by laser scribing technology. Polyimide (PI) can be converted into patterned porous graphene (PG) by laser’s irradiation in one step. The sound pressure level (SPL) of such TA device is related to laser power. The theoretical model of TA effect was established to analyze the relationship between the SPL and laser power. The theoretical results are in good agreement with experiment results. It was found that PG has a flat frequency response in the range of 5-20 kHz. This novel TA device has the advantages of one-step procedure, high flexibility, no mechanical vibration, low cost and so on. It can open wide applications in speakers, multimedia, medical, earphones, consumer electronics and many other aspects

  20. Concepts and Models Regarding the Behavior of Antiseismic Devices for the Base Isolation System

    Directory of Open Access Journals (Sweden)

    Polidor BRATU

    2013-07-01

    Full Text Available The paper presents the main antiseismic devices, as component elements of the base isolation systems, in such a manner that the functional and constructive parameters are correlated with the inertial and stiffness characteristics of the dynamic isolated building. Also, each device will be characterized through a rheological model, which conditions the eigenvalues and eigenvectors spectrum, as well as the dynamic response to an exterior excitation of a seismic nature. In this context, antiseismic devices defined and characterized by the European Standard EN 15129 will be presented. Based on the requirements formulated in the norm, the devices can be identified and their laws of evolution established and checked as follows: antiseismic devices with permanent rigid connection; antiseismic devices with rigid connections with respect to the instantaneous displacement and antiseismic devices dependent on the velocity and on the velocity variation in time.

  1. Infrared-sensitive electrochromic device based on VO2

    Science.gov (United States)

    Nakano, M.; Shibuya, K.; Ogawa, N.; Hatano, T.; Kawasaki, M.; Iwasa, Y.; Tokura, Y.

    2013-10-01

    The field-effect transistor (FET) provides an electrical switching function of current flowing through a channel surface by external voltage. Here, we report on a field-effect device that enables electrical switching of optical transmittance as well as conventional electrical current. We investigated optical properties of vanadium dioxide (VO2) thin film under the presence of electric field generated at the interface between VO2 and ionic liquid in a FET geometry, and found that the device exhibits clear electrochromic effect with large ON/OFF contrast only in the infrared region, potentially beneficial for energy-saving smart window applications as a voltage-tunable transparent heat-cutting filter.

  2. Picosecond dynamics of a silicon donor based terahertz detector device

    International Nuclear Information System (INIS)

    We report the characteristics of a simple complementary metal-oxide-semiconductor compatible terahertz detector device with low response time (nanoseconds) determined using a short-pulse, high intensity free-electron laser. The noise equivalent power was 1 × 10−11 W Hz−1/2. The detector has an enhanced response over narrow bands, most notably at 9.5 THz, with a continuum response at higher frequencies. Using such a device, the dynamics of donors in silicon can be explored, a system which has great potential for quantum information processing.

  3. Low cost nuclear spectrometer based on micro-controller device

    International Nuclear Information System (INIS)

    The present work describes the development of a gamma radiation Multichannel Analyzer device. That is to say, the development of a device able to display in the screen of a conventional computer a histogram of radioactive accounts (or accounts rate) received, in function of the different emission energies. It is a low cost implementation, oriented to mainly educational activities, but also applicable, within its limitations, to medium precision investigation works. In this first phase all the necessary one was implemented to detect the radioactive emissions, to measure them in energy, to store a complete spectrum and electronically to transfer it to a PC for its subsequent analysis. (author)

  4. ADHOC MOBILE WIRELESS NETWORK ENHANCEMENT BASED ON CISCO DEVICES

    Directory of Open Access Journals (Sweden)

    Mohamed E. Khedr

    2015-01-01

    Full Text Available Adhoc wireless networks become one of the most researchable areas in the studying of routing protocols depending on the Open System Interconnection (OSI Model. This paper use Cisco devices as a reference to enhance the performance of the network. This enhancement will be due to high processing, reliability, average cost, power consumption and accessibility. The aim of this research not only to get the cost down, it also to choose a time to time device to process the data as rapid as it can. Using NAT, Access List and DHCP protocols defined in Cisco (Graphical Unit Interface GUI of the (Command Line Interface CLI, the task can be made.

  5. Resource-efficient proces chains to manufacture patient-specific prosthetic fingers

    Directory of Open Access Journals (Sweden)

    Hagedorn-Hansen, D.

    2016-05-01

    Full Text Available The high cost of quality prostheses, together with the lack of trained prosthetists, makes it challenging to obtain prosthetic devices in developing communities. Modern 3D digitising techniques and additive manufacturing (AM technologies are gaining popularity in the bio-medical industry and, in the case of prosthesis production, reduce the need for a trained prosthetist. The objective of this research was to develop a new resource-efficient process chain for the manufacturing of prosthetic fingers using additive manufacturing technologies, and to compare it with the traditional (Sculptor process chain. Fused deposition modelling (FDM, open-source FDM, 3-dimensional printing (3DP, and stereolithography (SLA were evaluated in terms of their costs, time, material usage, and aesthetic quality. The surface qualities produced with the different additive manufacturing technologies were also compared. The results showed that 3DP was the preferred technology and was the best candidate for the production of prosthesis in terms of cost, quality, and time for developing communities. SLA produced the highest aesthetic quality prosthesis, but was the most expensive. It was concluded that using the additive manufacturing technology process chain to produce prosthetic fingers is faster and more cost effective than the traditional method.

  6. Gesture recognition in upper-limb prosthetics: a viability study using dynamic time warping and gyroscopes.

    Science.gov (United States)

    Dermitzakis, Konstantinos; Arieta, Alejandro Hernandez; Pfeifer, Rolf

    2011-01-01

    One of the significant challenges in the upper-limb-prosthetics research field is to identify appropriate interfaces that utilize the full potential of current state-of-the-art neuroprostheses. As the new generation of such prostheses paces towards approximating the human physiological performance in terms of movement dexterity and sensory feedback, it is clear that current non-invasive interfaces are still severely limited. Surface electromyography, the interface ubiquitously used in the field, is riddled with several shortcomings. Gesture recognition, an interface pervasively used in wearables and mobile devices, shows a strong potential as a non-invasive upper-limb prosthetic interface. This study aims at showcasing its potential in the field by using gyroscope sensors. To this end, we (1) explore the viability of Dynamic Time Warping as a classification method for upper-limb prosthetics and (2) look for appropriate sensor locations on the body. Results indicate an optimal classification rate of 97.53%, σ = 8.74 using a sensor located proximal to the endpoint performing a gesture. PMID:22255345

  7. Fabrication and electrical characteristics of graphene-based charge-trap memory devices

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Se J. [Dongguk University, Seoul (Korea, Republic of); Kim, Sung M.; Song, Emil B.; Wang, Kang L. [University of California Los Angeles, CA (United States); Seo, David H. [Samsung Electronics Co. Ltd., Yongin (Korea, Republic of); Seo, Sun A. [Sejong University, Seoul (Korea, Republic of)

    2012-07-15

    Graphene-based non-volatile charge-trap memory devices were fabricated and characterized to investigate the implementation effect of both 2-dimensional graphene and the 3-dimensional memory structure. The single-layer-graphene (SLG) channel devices exhibit larger memory windows compared to the multi-layer-graphene (MLG) channel devices. This originates from the gate-coupling strength being larger in SLG devices than in MLG devices. Namely, the electrostatic charge screening effect becomes enhanced upon increasing the number of graphene layers; therefore, the gate tunability is reduced in MLG compared to SLG. The results suggest that SLG is more desirable for memory applications than MLG.

  8. Development and Manufacture of Polymer-based Electrochromic Devices

    DEFF Research Database (Denmark)

    Jensen, Jacob; Hösel, Markus; Dyer, Aubrey L.;

    2015-01-01

    The field of organic electrochromics is reviewed here, with particular focus on how the “electrochromic” as a functional material can be brought from the current level of accurate laboratory synthesis and characterization to the device and application level through a number of suited roll-to-roll...... multilayer application and morphologically stable conjugated polymers....

  9. Optically switchable molecular device using microsphere based junctions

    Science.gov (United States)

    Faramarzi, V.; Raimondo, C.; Reinders, F.; Mayor, M.; Samorı, P.; Doudin, B.

    2011-12-01

    Metallic planar electrodes are bridged using microspheres coated with chemisorbed azobenzene self-assembled monolayers. The circuit exhibits light-induced switching, with reproducibility over 90%, as statistically determined and compared to junctions incorporating photo-insensitive alkanethiol layers. Microsphere interconnects provide direct access to molecular transport properties, with reliability and stability, making multifunctional molecular electronics devices possible.

  10. Nanotechnology Based Materials and Devices for Health Care

    Science.gov (United States)

    Srivastava, Deepaka; Cho, K.; Brenner, Don; Menon, Madhu; Andriotis, Antonis; Sagman, Uri; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on trends in NASA nanotechnology research and development, and future biotechnological applications for that nanotechnology. The presentation covers nanoelectronics, nanosensors, and nanomaterials, biomimetics, devices and materials for health care, carbon nanotubes, biosensors for astrobiology, solid-state nanopores for DNA sequencing, and protein nanotubes.

  11. Superlattice-based quantum devices: from theory to practical applications

    Science.gov (United States)

    Razeghi, M.

    2014-07-01

    The concepts of resonant tunneling and superlattices were first developed by Esaki and Tsu. What started with the new physics of the Esaki tunnel diode has matured into nanoscale engineering of semiconductors superlattices to create whole synthetic band structures. While working at Thomson CSF in France, Manijeh Razeghi went on to develop the metal-organic chemical vapor deposition (MOCVD) and molecular beam epitaxy growth of superlattice material as reported in my seminal volumes of The MOCVD Challenge. After years of considerable effort to bring this technology to maturity, we now see the results of this formidable new science in almost every electronic and photonic device that we encounter. Among the most successful triumphs are the type-II superlattice photodetectors and quantum cascade lasers - these technologies have demonstrated the beauty of turning fundamental concepts into practical devices, thanks to advanced growth technologies. This enables us to design and realize compact devices capable of mimicking or even exceeding nature. Using superlattice to pioneer the development of quantum systems is driving the research work at the Center for Quantum Devices.

  12. Shock Wave Based Biolistic Device for DNA and Drug Delivery

    Science.gov (United States)

    Nakada, Mutsumi; Menezes, Viren; Kanno, Akira; Hosseini, S. Hamid R.; Takayama, Kazuyoshi

    2008-03-01

    A shock wave assisted biolistic (biological ballistic) device has been developed to deliver DNA/drug-coated micro-projectiles into soft living targets. The device consists of an Nd:YAG laser, an optical setup to focus the laser beam and, a thin aluminum (Al) foil (typically 100 µm thick) which is a launch pad for the micro-projectiles. The DNA/drug-coated micro-particles to be delivered are deposited on the anterior surface of the foil and the posterior surface of the foil is ablated using the laser beam with an energy density of about 32×109 W/cm2. The ablation launches a shock wave through the foil that imparts an impulse to the foil surface, due to which the deposited particles accelerate and acquire sufficient momentum to penetrate soft targets. The device has been tested for particle delivery by delivering 1 µm size tungsten particles into liver tissues of experimental rats and in vitro test models made of gelatin. The penetration depths of about 90 and 800 µm have been observed in the liver and gelatin targets, respectively. The device has been tested for in vivo DNA [encoding β-glucuronidase (GUS) gene] transfer by delivering plasmid DNA-coated, 1-µm size gold (Au) particles into onion scale, tobacco leaf and soybean seed cells. The GUS activity was detected in the onion, tobacco and soybean cells after the DNA delivery. The present device is totally non-intrusive in nature and has a potential to get miniaturized to suit the existing medical procedures for DNA and/or drug delivery.

  13. Optimizing MEMS-Based Storage Devices for Mobile Battery-Powered Systems

    NARCIS (Netherlands)

    Khatib, Mohammed G.; Hartel, Pieter H.

    2010-01-01

    An emerging storage technology, called MEMS-based storage, promises nonvolatile storage devices with ultrahigh density, high rigidity, a small form factor, and low cost. For these reasons, MEMS-based storage devices are suitable for battery-powered mobile systems such as PDAs. For deployment in such

  14. Using of the Modern Semiconductor Devices Based on the SiC

    Directory of Open Access Journals (Sweden)

    Pavel Drabek

    2008-01-01

    Full Text Available This paper deals with possibility of application of the semiconductor devices based on the SiC (Silicon Carbide inthe power electronics. Basic synopsis of SiC based materials problems are presented, appreciation of their properties incomparison with current using power semiconductor devices ((IGBT, MOSFET, CoolFET transistors.

  15. Enhanced ultrasound for advanced diagnostics, ultrasound tomography for volume limb imaging and prosthetic fitting

    Science.gov (United States)

    Anthony, Brian W.

    2016-04-01

    Ultrasound imaging methods hold the potential to deliver low-cost, high-resolution, operator-independent and nonionizing imaging systems - such systems couple appropriate algorithms with imaging devices and techniques. The increasing demands on general practitioners motivate us to develop more usable and productive diagnostic imaging equipment. Ultrasound, specifically freehand ultrasound, is a low cost and safe medical imaging technique. It doesn't expose a patient to ionizing radiation. Its safety and versatility make it very well suited for the increasing demands on general practitioners, or for providing improved medical care in rural regions or the developing world. However it typically suffers from sonographer variability; we will discuss techniques to address user variability. We also discuss our work to combine cylindrical scanning systems with state of the art inversion algorithms to deliver ultrasound systems for imaging and quantifying limbs in 3-D in vivo. Such systems have the potential to track the progression of limb health at a low cost and without radiation exposure, as well as, improve prosthetic socket fitting. Current methods of prosthetic socket fabrication remain subjective and ineffective at creating an interface to the human body that is both comfortable and functional. Though there has been recent success using methods like magnetic resonance imaging and biomechanical modeling, a low-cost, streamlined, and quantitative process for prosthetic cup design and fabrication has not been fully demonstrated. Medical ultrasonography may inform the design process of prosthetic sockets in a more objective manner. This keynote talk presents the results of progress in this area.

  16. [Improving the speech with a prosthetic construction].

    Science.gov (United States)

    Stalpers, M J; Engelen, M; van der Stappen, J A A M; Weijs, W L J; Takes, R P; van Heumen, C C M

    2016-03-01

    A 12-year-old boy had problems with his speech due to a defect in the soft palate. This defect was caused by the surgical removal of a synovial sarcoma. Testing with a nasometer revealed hypernasality above normal values. Given the size and severity of the defect in the soft palate, the possibility of improving the speech with speech therapy was limited. At a centre for special dentistry an attempt was made with a prosthetic construction to improve the performance of the palate and, in that way, the speech. This construction consisted of a denture with an obturator attached to it. With it, an effective closure of the palate could be achieved. New measurements with acoustic nasometry showed scores within the normal values. The nasality in the speech largely disappeared. The obturator is an effective and relatively easy solution for palatal insufficiency resulting from surgical resection. Intrusive reconstructive surgery can be avoided in this way. PMID:26973984

  17. Projection display systems based on the Digital Micromirror Device (DMD)

    Science.gov (United States)

    Younse, Jack M.

    1995-09-01

    The DMD is a semiconductor light switch which is making an impact in digital light processingTM (DLP) applications. It is the world's largest micro-electro-mechanical structures (MEMS) device with chips ranging from 442-thousand to 2.3 million moving mirrors. The DMD operates in a bistable (binary) mode and fully supports the movement to all-digital display systems. Currently, DMD devices are being used to develop a family of projection display products. An overview of digital light processing systems will be given with emphasis on the performance of the first prototypes using this technology, including their value propositions. Finally, the general markets served by this technology, along with the advantages DMD technology offers, will be discussed.

  18. Tunable photonic bandgap fiber based devices for optical networks

    DEFF Research Database (Denmark)

    Alkeskjold, Thomas Tanggaard; Scolari, Lara; Rottwitt, Karsten;

    2005-01-01

    In future all optical networks one of the enabling technologies is tunable elements including reconfigurable routers, switches etc. Thus, the development of a technology platform that allows construction of tuning components is critical. Lately, microstructured optical fibers, filled with liquid...... crystals, have proven to be a candidate for such a platform. Microstructured optical fibers offer unique wave-guiding properties that are strongly related to the design of the air holes in the cladding of the fiber. These wave-guiding properties may be altered by filling the air holes with a material, for...... example a liquid crystal that changes optical properties when subjected to, for example, an optical or an electrical field. The utilization of these two basic properties allows design of tunable optical devices for optical networks. In this work, we focus on applications of such devices and discuss recent...

  19. Enhanced spin signal in nonlocal devices based on a ferromagnetic CoFeAl alloy

    Science.gov (United States)

    Bridoux, G.; Costache, M. V.; Van de Vondel, J.; Neumann, I.; Valenzuela, S. O.

    2011-09-01

    We systematically study the nonlocal spin signal in lateral spin valves based on CoFeAl injectors and detectors and compare the results with identically fabricated devices based on CoFe. The devices are fabricated by electron beam evaporation at room temperature. We observe a > 10-fold enhancement of the spin signal in the CoFeAl devices. We explain this increase as due to the formation of a highly spin-polarized Co2FeAl Heusler compound with large resistivity. These results suggest that Heusler compounds are promising candidates as spin polarized electrodes in lateral spin devices for future spintronic applications.

  20. Telemedicine Based on Mobile Devices and Mobile Cloud Computing

    OpenAIRE

    Lidong Wang; Cheryl Ann Alexander

    2014-01-01

    Mobile devices such as smartphones and tablets support kinds of mobile computing and services. They can access to the cloud or offload the computation-intensive part to the cloud computing resources. Mobile cloud computing (MCC) integrates the cloud computing into the mobile environment, which extends mobile devices’ battery lifetime, improves their data storage capacity and processing power, and improves their reliability and information security. In this paper, the applications of smartphon...

  1. Photonic Device Design Based on BBO for Ultrafast Frequency Doubling

    Science.gov (United States)

    Huang, Jin-Zhe; Yang, Zhong-Ying; Zhang, Liu-Yang; Pu, Shao-Zhi; Su, Lin

    2014-11-01

    Group velocity mismatch becomes the main obstacle for frequency conversion of ultrashort pulses due to dispersion. To solve the problem, one design is proposed for group velocity compensated second harmonic generation in a periodically modulated BBO crystal structure: the α-BBO/β-BBO multi-layer microstructure. The results show that the device can be well applied from the visible red to the near infrared region.

  2. Fabrication of polyimide based microfluidic channels for biosensor devices

    International Nuclear Information System (INIS)

    The ever-increasing complexity of the fabrication process of Point-of-care (POC) devices, due to high demand of functional versatility, compact size and ease-of-use, emphasizes the need of multifunctional materials that can be used to simplify this process. Polymers, currently in use for the fabrication of the often needed microfluidic channels, have limitations in terms of their physicochemical properties. Therefore, the use of a multipurpose biocompatible material with better resistance to the chemical, thermal and electrical environment, along with capability of forming closed channel microfluidics is inevitable. This paper demonstrates a novel technique of fabricating microfluidic devices using polyimide (PI) which fulfills the aforementioned properties criteria. A fabrication process to pattern microfluidic channels, using partially cured PI, has been developed by using a dry etching method. The etching parameters are optimized and compared to those used for fully cured PI. Moreover, the formation of closed microfluidic channel on wafer level by bonding two partially cured PI layers or a partially cured PI to glass with high bond strength has been demonstrated. The reproducibility in uniformity of PI is also compared to the most commonly used SU8 polymer, which is a near UV sensitive epoxy resin. The potential applications of PI processing are POC and biosensor devices integrated with microelectronics. (paper)

  3. The Challenge of Producing Fiber-Based Organic Electronic Devices

    Directory of Open Access Journals (Sweden)

    Tobias Könyves-Toth

    2014-07-01

    Full Text Available The implementation of organic electronic devices on fibers is a challenging task, not yet investigated in detail. As was shown earlier, a direct transition from a flat device structure to a fiber substrate is in principle possible. However, a more detailed investigation of the process reveals additional complexities than just the transition in geometry. It will be shown, that the layer formation of evaporated materials behaves differently due to the multi-angled incidence on the fibers surface. In order to achieve homogenous layers the evaporation process has to be adapted. Additionally, the fiber geometry itself facilitates damaging of its surface due to mechanical impact and leads to a high surface roughness, thereby often hindering commercial fibers to be used as substrates. In this article, a treatment of commercial polymer-coated glass fibers will be demonstrated that allows for the fabrication of rather flexible organic light-emitting diodes (OLEDs with cylindrical emission characteristics. Since OLEDs rely the most on a smooth substrate, fibers undergoing the proposed treatment are applicable for other organic electronic devices such as transistors and solar cells. Finally, the technique also supports the future fabrication of organic electronics not only in smart textiles and woven electronics but also in bent surfaces, which opens a wide range of applications.

  4. Status and Prospects of ZnO-Based Resistive Switching Memory Devices.

    Science.gov (United States)

    Simanjuntak, Firman Mangasa; Panda, Debashis; Wei, Kung-Hwa; Tseng, Tseung-Yuen

    2016-12-01

    In the advancement of the semiconductor device technology, ZnO could be a prospective alternative than the other metal oxides for its versatility and huge applications in different aspects. In this review, a thorough overview on ZnO for the application of resistive switching memory (RRAM) devices has been conducted. Various efforts that have been made to investigate and modulate the switching characteristics of ZnO-based switching memory devices are discussed. The use of ZnO layer in different structure, the different types of filament formation, and the different types of switching including complementary switching are reported. By considering the huge interest of transparent devices, this review gives the concrete overview of the present status and prospects of transparent RRAM devices based on ZnO. ZnO-based RRAM can be used for flexible memory devices, which is also covered here. Another challenge in ZnO-based RRAM is that the realization of ultra-thin and low power devices. Nevertheless, ZnO not only offers decent memory properties but also has a unique potential to be used as multifunctional nonvolatile memory devices. The impact of electrode materials, metal doping, stack structures, transparency, and flexibility on resistive switching properties and switching parameters of ZnO-based resistive switching memory devices are briefly compared. This review also covers the different nanostructured-based emerging resistive switching memory devices for low power scalable devices. It may give a valuable insight on developing ZnO-based RRAM and also should encourage researchers to overcome the challenges. PMID:27541816

  5. Stretchable inorganic nanomembrane electronics for healthcare devices

    Science.gov (United States)

    Kim, Dae-Hyeong; Son, Donghee; Kim, Jaemin

    2015-05-01

    Flexible or stretchable electronic devices for healthcare technologies have attracted much attention in terms of usefulness to assist doctors in their operating rooms and to monitor patients' physical conditions for a long period of time. Each device to monitor the patients' physiological signals real-time, such as strain, pressure, temperature, and humidity, etc. has been reported recently. However, their limitations are found in acquisition of various physiological signals simultaneously because all the functions are not assembled in one skin-like electronic system. Here, we describe a skin-like, multi-functional healthcare system, which includes single crystalline silicon nanomembrane based sensors, nanoparticle-integrated non-volatile memory modules, electro-resistive thermal actuators, and drug delivery. Smart prosthetics coupled with therapeutic electronic system would provide new approaches to personalized healthcare.

  6. A new repeatable, optical writing and electrical erasing device based on photochromism and electrochromism of viologen

    International Nuclear Information System (INIS)

    New optical writing and electrical erasing devices have been successfully fabricated that exploit the photochromism and electrochromism of viologen. In a preliminary study, both the structures of viologen and device were investigated in detail by UV–vis spectra in order to confirm their effects on the optical writing and electrical erasing performances of corresponding devices. For sandwiched, single and complementary devices based on benzyl viologen (BV 2+), only optical writing can be performed, not electrical erasing operations, which indicated these devices cannot realize optical information rewriting. For single and complementary devices based on styrene-functional viologen (V BV 2+) and acrylic-functional viologen (ACV 2+), optical writing and electrical erasing operations can be reversibly performed and optical information rewriting realized. It is clear that single devices based on V BV2+ and ACV2+ possess better performance accompanied with contrast without significant degradation and bleaching times and without significant deterioration over 10 repeated writing/erasing cycles. Furthermore, we put forward possible mechanisms for sandwiched, single and complementary devices based on V BV2+ and ACV2+ for the optical writing and electrical erasing operations. This study provides a new strategy to design optical writing and electrical erasing devices to realize optical information rewriting. (paper)

  7. An Analysis of Device-Free and Device-Based WiFi-Localization Systems

    OpenAIRE

    Aly, Heba; Youssef, Moustafa

    2015-01-01

    WiFi-based localization became one of the main indoor localization techniques due to the ubiquity of WiFi connectivity. However, indoor environments exhibit complex wireless propagation characteristics. Typically, these characteristics are captured by constructing a fingerprint map for the different locations in the area of interest. This fingerprint requires significant overhead in manual construction, and thus has been one of the major drawbacks of WiFi-based localization. In this paper, we...

  8. Neuro-Prosthetic Implants With Adjustable Electrode Arrays

    Science.gov (United States)

    Whitacre, Jay; DelCastillo, Linda Y.; Mojarradi, Mohammad; Johnson, Travis; West, William; Andersen, Richard

    2006-01-01

    Brushlike arrays of electrodes packaged with application-specific integrated circuits (ASICs) are undergoing development for use as electronic implants especially as neuro-prosthetic devices that might be implanted in brains to detect weak electrical signals generated by neurons. These implants partly resemble the ones reported in Integrated Electrode Arrays for Neuro-Prosthetic Implants (NPO-21198), NASA Tech Briefs, Vol. 27, No. 2 (February 2003), page 48. The basic idea underlying both the present and previously reported implants is that the electrodes would pick up signals from neurons and the ASICs would amplify and otherwise preprocess the signals for monitoring by external equipment. The figure presents a simplified and partly schematic view of an implant according to the present concept. Whereas the electrodes in an implant according to the previously reported concept would be microscopic wires, the electrodes according to the present concept are in the form of microscopic needles. An even more important difference would be that, unlike the previously reported concept, the present concept calls for the inclusion of microelectromechanical actuators for adjusting the depth of penetration of the electrodes into brain tissue. The prototype implant now under construction includes an array of 100 electrodes and corresponding array of electrode contact pads formed on opposite faces of a plate fabricated by techniques that are established in the art of microelectromechanical systems (MEMS). A mixed-signal ASIC under construction at the time of reporting the information for this article will include 100 analog amplifier channels (one amplifier per electrode). On one face of the mixed-signal ASIC there will be a solder-bump/micro-pad array that will have the same pitch as that of the electrode array, and that will be used to make the electrical and mechanical connections between the electrode array and the ASIC. Once the electrode array and the ASIC are soldered

  9. Ozone Treatment Improved the Resistive Switching Uniformity of HfAlO2 Based RRAM Devices

    Directory of Open Access Journals (Sweden)

    Lifeng Liu

    2015-01-01

    Full Text Available HfAlO2 based resistive random access memory (RRAM devices were fabricated using atomic layer deposition by modulating deposition cycles for HfO2 and Al2O3. Effect of ozone treatment on the resistive switching uniformity of HfAlO2 based RRAM devices was investigated. Compared to the as-fabricated devices, the resistive switching uniformity of HfAlO2 based RRAM devices with the ozone treatment is significantly improved. The uniformity improvement of HfAlO2 based RRAM devices is related to changes in compositional and structural properties of the HfAlO2 resistive switching film with the ozone treatment.

  10. A double data rate (DDR) architecture for OFDM based wireless consumer devices

    OpenAIRE

    Sherratt, R. S.; Cadenas, O.

    2010-01-01

    The creation of OFDM based Wireless Personal Area Networks (WPANs) has allowed high bit-rate wireless communication devices suitable for streaming High Definition video between consumer products as demonstrated in Wireless- USB. However, these devices need high clock rates, particularly for the OFDM sections resulting in high silicon cost and high electrical power. Acknowledging that electrical power in wireless consumer devices is more critical than the number of impl...

  11. AC transport in graphene-based Fabry-Perot devices

    OpenAIRE

    Rocha, Claudia G; Torres, Luis E. F. Foa; Cuniberti, Gianaurelio

    2009-01-01

    We report on a theoretical study of the effects of time-dependent fields on electronic transport through graphene nanoribbon devices. The Fabry-P\\'{e}rot interference pattern is modified by an ac gating in a way that depends strongly on the shape of the graphene edges. While for armchair edges the patterns are found to be regular and can be controlled very efficiently by tuning the ac field, samples with zigzag edges exhibit a much more complex interference pattern due to their peculiar elect...

  12. Programmable logic device based brushless DC motor control

    OpenAIRE

    Van den Bossche, Alex; Bozalakov, Dimitar; Vyncke, Thomas; Valchev, Vencislav

    2011-01-01

    In this article a three-phase BLDC motor controller for use in an Ultra-Light Electrical Vehicle is presented. The control is performed using a Programmable Logic Device (CPLD), which doesn’t require any additional processor. In this way a robust and low-complexity control is obtained. For extending the speed range of the BLDC, a phase advance circuit is implemented as well. The power consumption of the controller is very low which is an interesting feature in battery applications.

  13. Phthalocyanine based 1D nanowires for device applications

    Science.gov (United States)

    Saini, Rajan; Mahajan, Aman; Bedi, R. K.

    2012-06-01

    1D nanowires (NWs) of Cu (II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-Phthalocyanine (CuPc(OBu)8) molecule have been grown on different substrates by cost effective solution processing technique. The density of NWs is found to be strongly dependent on the concentration of solution. The possible formation mechanism of these structures is π-π interaction between phthalocyanine molecules. The improved conductivity of these NWs as compared to spin coated film indicates their potential for molecular device applications.

  14. Holographic optical traps for atom-based topological Kondo devices

    Science.gov (United States)

    Buccheri, F.; Bruce, G. D.; Trombettoni, A.; Cassettari, D.; Babujian, H.; Korepin, V. E.; Sodano, P.

    2016-07-01

    The topological Kondo (TK) model has been proposed in solid-state quantum devices as a way to realize non-Fermi liquid behaviors in a controllable setting. Another motivation behind the TK model proposal is the demand to demonstrate the quantum dynamical properties of Majorana fermions, which are at the heart of their potential use in topological quantum computation. Here we consider a junction of crossed Tonks–Girardeau gases arranged in a star-geometry (forming a Y-junction), and we perform a theoretical analysis of this system showing that it provides a physical realization of the TK model in the realm of cold atom systems. Using computer-generated holography, we experimentally implement a Y-junction suitable for atom trapping, with controllable and independent parameters. The junction and the transverse size of the atom waveguides are of the order of 5 μm, leading to favorable estimates for the Kondo temperature and for the coupling across the junction. Since our results show that all the required theoretical and experimental ingredients are available, this provides the demonstration of an ultracold atom device that may in principle exhibit the TK effect.

  15. An expert system of choosing lower limb (thigh) prostheses and diagnosis of the prosthetics quality (Part 2)

    International Nuclear Information System (INIS)

    The authors review an expert system (ES) of diagnosing the prosthetics quality, elucidate problems of the ES functioning within the framework of the general ES. Special attention is paid to the description of the knowledge and data bases, to the algorithms of direct and reverse illegible logical data output in taking decisions as to defects of the patient's prosthesis in accordance with the signs observable. The work of the ES is demonstrated with special reference to concrete cases. Analysis of the estimates of the sensitivity to the initial data is made. The ES presents knowledge in depth, being designed in two versions: for practical (individual and mass) prosthetics and training purposes

  16. A point-based rendering approach for real-time interaction on mobile devices

    Institute of Scientific and Technical Information of China (English)

    LIANG XiaoHui; ZHAO QinPing; HE ZhiYing; XIE Ke; LIU YuBo

    2009-01-01

    Mobile device is an Important interactive platform. Due to the limitation of computation, memory, display area and energy, how to realize the efficient and real-time interaction of 3D models based on mobile devices is an important research topic. Considering features of mobile devices, this paper adopts remote rendering mode and point models, and then, proposes a transmission and rendering approach that could interact in real time. First, improved simplification algorithm based on MLS and display resolution of mobile devices is proposed. Then, a hierarchy selection of point models and a QoS transmission control strategy are given based on interest area of operator, interest degree of object in the virtual environment and rendering error. They can save the energy consumption. Finally, the rendering and interaction of point models are completed on mobile devices. The experiments show that our method is efficient.

  17. Two-degree-of-freedom powered prosthetic wrist

    Directory of Open Access Journals (Sweden)

    Peter J. Kyberd, PhD

    2011-07-01

    Full Text Available Prosthetic wrists need to be compact. By minimizing space requirements, a wrist unit can be made for people with long residual limbs. This prosthetic wrist uses two motors arranged across the arm within the envelope of the hand. The drive is transmitted by a differential so that it produces wrist flexion and extension, pronation and supination, or a combination of both. As a case study, it was controlled by a single-prosthesis user with pattern recognition of the myoelectric signals from the forearm. The result is a compact, two-degree-of-freedom prosthetic wrist that has the potential to improve the functionality of any prosthetic hand by creating a hand orientation that more closely matches grasp requirements.

  18. A uniform XML-based approach to manage data acquisition hardware devices

    CERN Document Server

    Brigljevic, V; Cano, E; Cittolin, Sergio; Erhan, S; Gigi, D; Glege, F; Gómez-Reino, Robert; Gulmini, M; Gutleber, J; Jacobs, C; Kozlovszky, Miklos; Larsen, H; Magrans de Abril, Ildefons; Meijers, F; Meschi, E; Murray, S; Oh, A; Orsini, L; Pollet, L; Rácz, A; Samyn, D; Scharff-Hansen, P; Shepelevich, S; Sphicas, Paris; Schwick, C

    2004-01-01

    A comprehensive model based on XML technologies to interface data acquisition hardware devices for configuration and control purposes is presented. The model builds upon the use of a unified syntax for describing hardware devices, configuration data, test results as well as control sequences. The integration of the model with the online software framework of the CMS experiment is under evaluation. (17 refs).

  19. A micro-scale hot-surface device based on non-radiative carrier recombination

    NARCIS (Netherlands)

    Kovalgin, A.Y.; Holleman, J.; Iordache, G.

    2004-01-01

    This work employs the idea of making micro-scale hot-surface devices (e.g. sensors, flow meters, micro reactors, etc) based on generation of heat due to nonradiative recombination of carriers in a thin (13 nm) poly silicon surface layer. An important part of the device is a nano-scale (10-100 nm) co

  20. LC Filter Design for Wide Band Gap Device Based Adjustable Speed Drives

    DEFF Research Database (Denmark)

    Vadstrup, Casper; Wang, Xiongfei; Blaabjerg, Frede

    This paper presents a simple design procedure for LC filters used in wide band gap device based adjustable speed drives. Wide band gap devices offer fast turn-on and turn-off times, thus producing high dV/dt into the motor terminals. The high dV/dt can be harmful for the motor windings and bearings...

  1. Silicon based nanogap device for investigating electronic transport through 12 nm long oligomers

    DEFF Research Database (Denmark)

    Strobel, S.; Albert, E.; Csaba, G.; Lugli, P.; Søndergaard, Roar R.; Bundgaard, Eva; Norrman, Kion; Krebs, Frederik C; Hansen, A.G.; Tornow, M.

    We have fabricated vertical nanogap electrode devices based on Silicon-on-Insulator (SOI) substrates for investigating the electronic transport properties of long, conjugated molecular wires. Our nanogap electrode devices comprise smooth metallic contact pairs situated at the sidewall of an SOI s...

  2. Demonstration of a PDMS based hybrid grating and Fresnel lens (G-Fresnel) device.

    Science.gov (United States)

    Yang, Chuan; Shi, Kebin; Edwards, Perry; Liu, Zhiwen

    2010-11-01

    A hybrid device that we term G-Fresnel (i.e., grating and Fresnel) is demonstrated. It fuses the functions of a grating and a Fresnel lens into a single device. We have fabricated the G-Fresnel device by using polydimethylsiloxane (PDMS) based soft lithography. Three-dimensional surface profilometry has been performed to examine the device quality. We have also conducted optical characterizations to confirm its dual focusing and dispersing properties. The G-Fresnel can be useful for the development of miniature optical spectrometers as well as emerging optofluidic applications. PMID:21164696

  3. Cloud Based Application Development for Accessing Restaurant Information on Mobile Device using LBS

    OpenAIRE

    Shetty, Keerthi S.; Sanjay Singh

    2011-01-01

    Over the past couple of years, the extent of the services provided on the mobile devices has increased rapidly. A special class of service among them is the Location Based Service(LBS) which depends on the geographical position of the user to provide services to the end users. However, a mobile device is still resource constrained, and some applications usually demand more resources than a mobile device can a ord. To alleviate this, a mobile device should get resources from an external source...

  4. A selector device based on graphene-oxide heterostructures for memristor crossbar applications

    Science.gov (United States)

    Wang, Miao; Lian, Xiaojuan; Pan, Yiming; Zeng, Junwen; Wang, Chengyu; Liu, Erfu; Wang, Baigeng; Yang, J. Joshua; Miao, Feng; Xing, Dingyu

    2015-08-01

    Most of the potential applications of memristive devices adopt crossbar architecture for ultra-high density. One of the biggest challenges of the crossbar architecture is severe residue leakage current (sneak path) issue. A possible solution is introducing a selector device with strong nonlinear current-voltage ( I- V) characteristics in series with each memristor in crossbar arrays. Here, we demonstrate a novel selector device based on graphene-oxide heterostructures, which successfully converts a typical linear TaO x memristor into a nonlinear device. The origin of the nonlinearity in the heterostructures is studied in detail, which highlights an important role of the graphene-oxide interfaces.

  5. Assessment of preload in carbon coated prosthetic screws

    OpenAIRE

    Dilcele Silva Moreira Dziedzic; Juliane Nhata; Vanessa Helena Jamcoski; Maurício Dziedzic

    2012-01-01

    Introduction: The mechanical aspects of tightening screws over implants are important to ensure a successful prosthetic rehabilitation. Screw loosening is a common problem that can be avoided with passive adaptation of the components and an increased tensile force developed in the screw, a preload. Objective: This in vitro study evaluated the effect on preload of a carbon lubricant deposited on the surface of titanium alloy prosthetic screws: conventional Ti6Al4V and surface enhanced. Materia...

  6. A biosensor based on graphene nanoribbon with nanopores: a first-principles devices-design

    Institute of Scientific and Technical Information of China (English)

    Ouyang Fang-Ping; Peng Sheng-Lin; Zhang Hua; Weng Li-Bo; Xu Hui

    2011-01-01

    A biosensor device, built from graphene nanoribbons (GNRs) with nanopores, was designed and studied by firstprinciples quantum transport simulation. We have demonstrated the intrinsic transport properties of the device and the effect of different nucleobases on device properties when they are located in the nanopores of GNRs. It was found that the device's current changes remarkably with the species of nucleobases, which originates from their different chemical compositions and coupling strengths with GNRs. In addition, our first-principles results clearly reveal that the distinguished ability of a device's current depends on the position of the pore to some extent. These results may present a new way to read off the nucleobases sequence of a single-stranded DNA (ssDNA) molecule by such GNRs-based device with designed nanopores

  7. [Chemiluminescence of whole saliva in antioxidant treatment of prosthetic bed tissues].

    Science.gov (United States)

    Tunian, M Iu; Lalaian, B K; Zakarian, A E; Grigorian, K L; Pogosian, G A; Egiazarian, A V

    2010-03-01

    Inflammatory reaction is always accompanied by increased intensity of free-radical oxidation, especially when the phenomena of hypoxia and microcirculatory disorders that occur during the development of side-effects of acrylic removable dentures. This study determined the effectiveness of adaptogens, antioxidants in the complex treatment of diseases of tissues prosthetic field and their influence on the processes of LPO in whole mixed unstimulated saliva. Formed in the reaction to initiate the process of oxygen radicals (OH, RO, O(2)), initiate the formation of lipid peroxide radicals RO(2) biological substrate, the recombination of which leads to the emergence of unsustainable tetroxids, which decays with the release of light quanta. This luminescence is recorded as an amplified current of the photomultiplier, the registration systems. The results suggest the intensive formation of free radicals and peroxides in diseased tissue prosthetic field. Probably the main reason for increasing free-radical oxidation is the release of peroxidase from the crumbling inflammation, phagocytes (mainly neutrophils). The process of peroxidation contributes to an increase in blood supply to inflamed tissues, leading to local enrichment of oxygen, as well as toxic effects of acrylic bases of partial and complete removable dentures in the prosthetic field of tissue. Effect of antioxidants in combination with traditional treatment in 70 patients with periodontal disease and prosthetic bed was assessed by chemiluminescence analysis of whole mixed unstimulated saliva. The level of lipid peroxidation and chemiluminescence activity exceeded the normal values in the 1,5-2 - twice before the treatment. After treatment with antioxidants, these parameters decreased and increased during remission. Thus, studies to determine the status of saliva chemiluminescence method to treat and monitor the dynamics after treatment of periodontitis tissues supporting teeth prosthetic field in the control

  8. Conjugated polymer based active electric-controlled terahertz device

    Science.gov (United States)

    Zhong, Liang; Zhang, Bo; He, Ting; Lv, Longfeng; Hou, Yanbing; Shen, Jingling

    2016-03-01

    A modulation of terahertz response in a highly efficient, electric-controlled conjugated polymer-silicon hybrid device with low photo-excitation was investigated. The polymer-silicon forms a hybrid structure, where the active depletion region modifies the semiconductor conductivity in real time by applying an external bias voltage. The THz transmission was efficiently modulated by effective controlling. In a THz-TDS system, the modulation depth reached nearly 100% when the applied voltage was 3.8 V at an external laser intensity of 0.3 W/cm2. The saturation voltage decreased with increasing photo-excited intensity. In a THz-CW system, a significant decline in THz transmission was also observed with increasing applied bias voltage. This reduction in THz transmission is induced by the enhancement of carrier density.

  9. Fabrication of polyimide based microfluidic channels for biosensor devices

    DEFF Research Database (Denmark)

    Zulfiqar, Azeem; Pfreundt, Andrea; Svendsen, Winnie Edith;

    2015-01-01

    fabrication of the often needed microfluidic channels, have limitations in terms of their physicochemical properties. Therefore, the use of a multipurpose biocompatible material with better resistance to the chemical, thermal and electrical environment, along with capability of forming closed channel...... microfluidics is inevitable. This paper demonstrates a novel technique of fabricating microfluidic devices using polyimide (PI) which fulfills the aforementioned properties criteria. A fabrication process to pattern microfluidic channels, using partially cured PI, has been developed by using a dry etching...... method. The etching parameters are optimized and compared to those used for fully cured PI. Moreover, the formation of closed microfluidic channel on wafer level by bonding two partially cured PI layers or a partially cured PI to glass with high bond strength has been demonstrated. The reproducibility in...

  10. In vitro activity of ceftaroline against staphylococci from prosthetic joint infection.

    Science.gov (United States)

    Park, Kyung-Hwa; Greenwood-Quaintance, Kerryl E; Patel, Robin

    2016-02-01

    We tested the in vitro activity of ceftaroline by Etest against staphylococci recovered from patients with prosthetic joint infection, including 97 Staphylococcus aureus isolates (36%, oxacillin resistant) and 74 Staphylococcus epidermidis isolates (74%, oxacillin resistant). Ceftaroline inhibited all staphylococci at ≤0.5 μg/mL. The ceftaroline MIC(90/50) values for methicillin-susceptible S. aureus, methicillin-susceptible S. epidermidis, methicillin-resistant S. aureus, and methicillin-resistant S. epidermidis were 0.19/0.125, 0.094/0.047, 0.5/0.38, and 0.38/0.19 μg/mL, respectively. Based on these in vitro findings, ceftaroline should be further evaluated as a potential therapeutic option for the treatment of prosthetic joint infection caused by methicillin-susceptible and methicillin-resistant S. aureus and S. epidermidis. PMID:26602948

  11. Transfer-Free, Wafer-Scale Manufacturing of Graphene-Based Electromechanical Resonant Devices

    Science.gov (United States)

    Cullinan, Michael; Gorman, Jason

    2013-03-01

    Nanoelectromechanical (NEMS) resonators offer the potential to extend the limits of force and mass detection due to their small size, high natural frequencies and high Q-factors. Graphene-based NEMS resonators are particularly promising due to their high elastic modulus and atomic thickness. However, widespread use of graphene in such systems is limited by the way in which graphene-based devices are typically fabricated. Most graphene-based NEMS devices are fabricated in a ``one-off'' manner using slow, limited scale methods such as mechanical exfoliation, electron beam lithography, or transfer from copper foils which can't be incorporated into standard micro/nanofabrication lines. This talk will present a method that can be used to manufacture graphene-based NEMS devices at the wafer scale using conventional microfabrication techniques. In this method graphene is grown directly on thin film copper using chemical vapor deposition. The copper film is then patterned and etched to produce graphene-based NEMS resonators. This talk will also address some of the challenges in fabricating a large number of graphene devices at the wafer scale including achieving high uniformity across the wafer, increasing device-to-device repeatability, and producing high device yields.

  12. Dental Prosthetic Status and Prosthetic Needs of Institutionalised Elderly Population in Oldage Homes of Jabalpur City, Madhya Pradesh, India

    OpenAIRE

    Deogade, Suryakant C.; Vinay, S.; Naidu, Sonal

    2012-01-01

    Oral disorders are cumulative throughout life and hence unfavourable outcomes are likely to be greatest among the elderly. A descriptive cross-sectional study was conducted among institutionalized geriatric population in old-age homes of Jabalpur city, Madhya Pradesh, to assess their prosthetic status and prosthetic needs. A cross-sectional survey was conducted in all the four old-age homes of Jabalpur city, Madhya Pradesh state, India. All residents aged 60 years and above formed the study p...

  13. Flexible Graphene-based Energy Storage Devices for Space Application Project

    Science.gov (United States)

    Calle, Carlos I.

    2014-01-01

    Develop prototype graphene-based reversible energy storage devices that are flexible, thin, lightweight, durable, and that can be easily attached to spacesuits, rovers, landers, and equipment used in space.

  14. Thin film lithium-based batteries and electrochromic devices fabricated with nanocomposite electrode materials

    Science.gov (United States)

    Gillaspie, Dane T; Lee, Se-Hee; Tracy, C. Edwin; Pitts, John Roland

    2014-02-04

    Thin-film lithium-based batteries and electrochromic devices (10) are fabricated with positive electrodes (12) comprising a nanocomposite material composed of lithiated metal oxide nanoparticles (40) dispersed in a matrix composed of lithium tungsten oxide.

  15. RSPF-based Prognosis Framework for Estimation of Remaining Useful Life in Energy Storage Devices

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper presents a case study where a RSPF-based prognosis framework is applied to estimate the remaining useful life of an energy storage device (Li-Ion...

  16. Optical Deposition of Carbon Nanotubes for Fiber-based Device Fabrication

    OpenAIRE

    Kashiwagi, Ken; Yamashita, Shinji

    2010-01-01

    In this chapter, we have proposed and demonstrated the optical deposition method of CNTs. After brief introduction of this chapter (section 1), we explained the general characteristics, optical properties, and optical devices based on CNTs in section 2. From

  17. Long-term stability of neural prosthetic control signals from silicon cortical arrays in rhesus macaque motor cortex

    Science.gov (United States)

    Chestek, Cynthia A.; Gilja, Vikash; Nuyujukian, Paul; Foster, Justin D.; Fan, Joline M.; Kaufman, Matthew T.; Churchland, Mark M.; Rivera-Alvidrez, Zuley; Cunningham, John P.; Ryu, Stephen I.; Shenoy, Krishna V.

    2011-08-01

    Cortically-controlled prosthetic systems aim to help disabled patients by translating neural signals from the brain into control signals for guiding prosthetic devices. Recent reports have demonstrated reasonably high levels of performance and control of computer cursors and prosthetic limbs, but to achieve true clinical viability, the long-term operation of these systems must be better understood. In particular, the quality and stability of the electrically-recorded neural signals require further characterization. Here, we quantify action potential changes and offline neural decoder performance over 382 days of recording from four intracortical arrays in three animals. Action potential amplitude decreased by 2.4% per month on average over the course of 9.4, 10.4, and 31.7 months in three animals. During most time periods, decoder performance was not well correlated with action potential amplitude (p > 0.05 for three of four arrays). In two arrays from one animal, action potential amplitude declined by an average of 37% over the first 2 months after implant. However, when using simple threshold-crossing events rather than well-isolated action potentials, no corresponding performance loss was observed during this time using an offline decoder. One of these arrays was effectively used for online prosthetic experiments over the following year. Substantial short-term variations in waveforms were quantified using a wireless system for contiguous recording in one animal, and compared within and between days for all three animals. Overall, this study suggests that action potential amplitude declines more slowly than previously supposed, and performance can be maintained over the course of multiple years when decoding from threshold-crossing events rather than isolated action potentials. This suggests that neural prosthetic systems may provide high performance over multiple years in human clinical trials.

  18. Peri-prosthetic fracture vibration testing

    Energy Technology Data Exchange (ETDEWEB)

    Cruce, Jesse R [Los Alamos National Laboratory; Erwin, Jenny R [Los Alamos National Laboratory; Remick, Kevin R [Los Alamos National Laboratory; Cornwell, Phillip J [Los Alamos National Laboratory; Menegini, R. Michael [INDIANA UNIV.; Racanelli, Joe [STRYKER ORTHOPARDICS

    2010-11-08

    The purpose of this study was to establish a test setup and vibration analysis method to predict femoral stem seating and prevent bone fracture using accelerometer and force response data from an instrumented stem and impactor. This study builds upon earlier studies to identify a means to supplement a surgeon's tactile and auditory senses by using damage identification techniques normally used for civil and mechanical structures. Testing was conducted using foam cortical shell sawbones prepared for stems of different geometries. Each stem was instrumented with an accelerometer. Two impactor designs were compared: a monolithic impactor and a two-piece impactor, each with an integrated load cell and accelerometer. Acceleration and force measurements were taken in the direction of impaction. Comparisons between different methods of applying an impacting force were made, including a drop tower and a surgical hammer. The effect of varying compliance on the data was also investigated. The ultimate goal of this study was to assist in the design of an integrated portable data acquisition system capable of being used in future cadaveric testing. This paper will discuss the experimental setup and the subsequent results of the comparisons made between impactors, prosthetic geometries, compliances, and impact methods. The results of this study can be used for both future replicate testing as well as in a cadaveric environment.

  19. Design characteristics of pediatric prosthetic knees.

    Science.gov (United States)

    Andrysek, Jan; Naumann, Stephen; Cleghorn, William L

    2004-12-01

    We examined whether pediatric prosthetic single-axis knees can theoretically provide the beneficial functional characteristics of polycentric knees and the design considerations needed to realize this. Five children and their parents provided subjective opinions of the relative importance of functional requirements (FRs) for the knee. FRs related to comfort, fatigue, stability, and falling were found to be of high importance, while sitting appearance and adequate knee flexion were of lower importance. Relationships were drawn between these FRs and deductions were made regarding the importance of associated design parameters. Stance-phase control was rated to be of greatest importance followed by toe clearance. Models were developed for five knees including four- and six-bar knees, corresponding to two commercially available components, and for three configurations of a single-axis knee. Stance-phase control, specifically stability after heel-strike and swing-phase initiation at push-off, and toe clearance were simulated. The results suggest that a single-axis knee design incorporating stance-phase control will mutually satisfy the identified set of highly and moderately important FRs. PMID:15614992

  20. Influence of carrier dynamics on the modulation bandwidth of quantum-dot based nanocavity devices

    DEFF Research Database (Denmark)

    Lorke, Michael; Nielsen, Torben Roland; Mørk, Jesper

    2010-01-01

    We theoretically investigate the modulation response of quantum-dot based nanocavity light emitting devices. For high Purcell enhancement factors, our theory predicts the possibility of decreasing the modulation bandwidth with increasing scattering rate into the lasing quantum-dot state. This cou...... counterintuitive effect is investigated using a microscopic semiconductor model. The resulting guidelines for possible optimizations of quantum-dot based nanocavity laser devices are given....

  1. Seismic behaviour of an asymmetric three-dimensional steel frame with base isolation devices

    OpenAIRE

    Barros, R.C.; Braz-César, M.T.

    2006-01-01

    A parametric study on the use of base isolation devices in frame building structures is undertaken. Frames were analysed with regular geometry starting from a baseframe (BF), from which more complex frames were created by association of BF in height above a certain asymmetric plant. The modularity of the BF facilitates the analysis of the results, allowing for parametric studies on the use of base isolation devices in more complex geometries. To conduct the computational studie...

  2. Fabrication of Optical Devices Based on Printable Photonics Technology and Its Application for Biosensor

    Science.gov (United States)

    Endo, Tatsuro; Okuda, Norimichi; Yanagida, Yasuko; Tanaka, Satoru; Hatsuzawa, Takeshi

    The specific optical characteristics which can be observed nanostructured optical device have great potentials for applying to several applications such as lifescience, optical communications, and data storage. Application of nanostrcutured optical device to industry, we suggest “printable photonics technology” for fabrication of nanostructured optical device based on nanoimprint lithography (NIL). In this study, using printable photonics technology, fabrication of flexible photonic crystal (PC) and its application for biosensor was performed. Using printable photonics technology-based PC for biosensing application, high sensitive detection of protein adsorption (detection limit: 1 pg/ml) could be detected.

  3. Graphene based Photonics Devices for Remote Sensing Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop scalable graphene-based bolometer technology. Use low pressure chemical vapor deposition (LPCVD) technique to grow large area graphene. Develop a process to...

  4. Response characteristics of base-isolated structure with hardening-stopper type fail-safe devices

    International Nuclear Information System (INIS)

    In this study, a fail-safe mechanism for backing up the reliability of an isolator device is being developed predicated on the application of a base isolation system to nuclear fuel facilities. 'Fail-safe' is often understood to mean that when a device loses its function, a separate mechanism will work in order that there will be no trouble with regard to safety. However, since it may be considered extremely difficult to support loads without any trouble when the base isolation device itself loses its function, the term will be used here to mean that the base isolation device is supported so that it will not lose its function. The two points below will be made the objectives of design as workings of the fail-safe system in this study. 1) Response Displacement Control: Suppresses excessive deformation of the base isolation device even in case of input of an earthquake greater than the design seismic force to prevent destruction of the base isolation device, superstructure, and connected piping. 2) Response Acceleration Control: Reduces acceleration transmitted to the superstructure insofar as possible by action of the fail-safe mechanism. Characteristics tests and analyses, and earthquake observations using reduced-scale model have now been carried out to grasp the response characteristics of a base isolation combining high-damping rubber bearings and hardening-stopper type fail-safe mechanisms, and the results will be reported below. (author)

  5. The design, development, and evaluation of a prototypic, prosthetic venous valve

    Directory of Open Access Journals (Sweden)

    Rittgers Stanley E

    2008-09-01

    Full Text Available Abstract Background Chronic venous insufficiency is a serious disease for which there is no clearly successful surgical treatment. Availability of a proven prosthetic vein valve could provide such an option by reducing venous reflux while permitting normal antegrade flow. Methods A new prosthetic vein valve design has been developed which mimics the function of a natural valve by ensuring complete closure of the leaflets with minimal obstruction for antegrade flow. A 2:1 mock-up of the device was tested to evaluate its ability to prevent regurgitation and several key modifications were made. A subsequently re-designed 1:1 prototype was then built in 4 slightly different size configurations and then each tested under physiologic conditions of pulsatile flow in both supine and standing positions. Results Each of the configurations showed acceptable amounts of antegrade resistance and effective orifice area and showed low values of regurgitation and % reflux with two of the prototype configurations (flange lengths of 2.5 mm and 3.75 mm having corresponding values of 97%, 11 mL, and 36%, respectively. These values are particularly striking when compared to the corresponding regurgitation and % reflux values of 60 mL and 205%, respectively, when no device is present. Conclusion The results of this study show that this prototype vein valve design is capable of providing significant relief of reflux under realistic conditions without inducing any increase in antegrade flow resistance and warrants further testing with in vivo models.

  6. Detection of nucleic acids by graphene-based devices: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hua [School of Physics and Electronics, Central South University, Changsha 410083 (China); School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410114 (China); Xu, Hui, E-mail: xuhui@csu.edu.cn, E-mail: ouyangfp06@tsinghua.org.cn; Ni, Xiang; Lin Peng, Sheng; Liu, Qi; Ping OuYang, Fang, E-mail: xuhui@csu.edu.cn, E-mail: ouyangfp06@tsinghua.org.cn [School of Physics and Electronics, Central South University, Changsha 410083 (China)

    2014-04-07

    Based on first-principles quantum transport calculations, we design a graphene-based biosensor device, which is composed of graphene nanoribbons electrodes and a biomolecule. It is found that when different nucleobases or poly nucleobase chains are located in the nanogap, the device presents completely different transport properties, showing different current informations. And the change of currents from 2 to 5 orders of magnitude for four different nucleobases suggests a great ability of discrimination by utilizing such a device. The physical mechanism of this phenomenon originates from their different chemical composition and structure. Moreover, we also explore the coupling effect of several neighboring bases and the size effect of the nanogap on transport properties. Our results show the possibility of rapid sequencing DNA by measuring such a transverse-current of the device, and provide a new idea for sequencing DNA.

  7. Hand-held based near-infrared optical imaging devices: a review.

    Science.gov (United States)

    Erickson, Sarah J; Godavarty, Anuradha

    2009-06-01

    Near-infrared (NIR) optical imaging is a non-invasive and non-ionizing modality that is emerging as a diagnostic/prognostic tool for breast cancer and other applications related to functional brain mapping. In recent years, hand-held based optical imaging devices are developed for clinical translation of the technology, as opposed to the various bulky optical imagers available. Herein, we review the different hand-held based NIR devices developed to date, in terms of the measurement techniques implemented (continuous wave, time or frequency-domain), the imaging methods used, and the specific applications towards which they were applied. The advantages and disadvantages of the different hand-held optical devices are described and also compared with respect to a novel hand-held based device currently developed in our Optical Imaging Laboratory towards three-dimensional tomography studies. PMID:19054704

  8. Internal Location Based System For Mobile Devices Using Passive RFID And Wireless Technology

    CERN Document Server

    Potgantwar, A D

    2010-01-01

    We have explored our own innovative work about the design & development of internal location identification system for mobile devices based on integration of RFID and wireless technology. The function of our system is based on strategically located passive RFID tags placed on objects around building which are identified using an RFID reader attached to a mobile device. The mobile device reads the RFID tag and through the wireless network, sends the request to the server. The server resolves the request and sends the desired location based information back to the mobile device. We had addressed that we can go through the RFID technology for internal location identification (indoor), which provides us better location accuracy because of no contact between the tag and the reader, and the system requires no line of sight. In this paper we had also focused on the issues of RFID technologies i.e. Non line of sight & High inventory speeds.

  9. Preliminary evaluation of the tactile feedback system based on artificial skin and electrotactile stimulation.

    Science.gov (United States)

    Franceschi, M; Seminara, L; Pinna, L; Dosen, S; Farina, D; Valle, M

    2015-08-01

    This research is motivated by the need of integrating cutaneous sensing into a prosthetic device, enabling a bidirectional communication between the amputee and the prosthetic limb. An electronic skin based on piezoelectric polymer sensors transduces mechanical contact into electrical response which is conveyed to the human subject by electrotactile stimulation. Rectangular electrode arrays are placed on each patient's forearm and experiments are conducted on five different subjects to determine how well the orientation, position and direction of single lines are recognized. Overall, subjects discriminate the different touch modalities with acceptable success rates. In particular, the direction is identified at best and longitudinal lines on the patient's skin are recognized with the highest success rates. These preliminary results assess the feasibility of the artificial skin - electrostimulation system for prosthetic applications. PMID:26737307

  10. Code division in optical memory devices based on photon echo

    Science.gov (United States)

    Kalachev, Alexey A.; Vlasova, Daria D.

    2006-03-01

    The theory of multi-channel optical memory based on photon echo is developed. It is shown that under long-lived photon echo regime the writing and reading of information with code division is possible using phase modulation of reference and reading pulses. A simple method for construction of a system of noise-like signals, which is based on the segmentation of Frank sequence is proposed. It is shown that in comparison to the system of random biphase signals this system leads to the efficient decreasing of mutual influence of channels and increasing of random/noise ratio under reading of information.

  11. State-of-the-art materials used for maxillofacial prosthetic reconstruction.

    Science.gov (United States)

    Lontz, J F

    1990-04-01

    The present state-of-the-art rests primarily on three general types of polymeric materials based on chemical configurations, that of polyacrylates, polydimethylsiloxane, and segmented block polyetherurethanes. Each of these types is currently prominent in a wide range of dental prosthodontics and surgical prosthetics with continued chemical variants emerging to attain enhanced biocompatibility for safety and effectiveness. However, owing to the disproportionally lower demand, the state-of-the-art for maxillofacial restorative prosthetics has not focused adequately on the specific array of the properties needed for the ideal prosthesis. To approach the ideality will require synthesizing new molecular configurations adjusted with component structures either as block copolymers or as intermediate oligomers. The synthetic effects must have a comprehensive plan of immediate assessments on terms of biocompatibility for safety to orofacial tissues and effective durability against all conceivable deterioration of the chemical structure. Above all, inasmuch as the skilled art and techniques of maxillofacial prosthetics is a custom-made specialty allied to the prosthodontics, the improved material for ideality should be readily amenable to molding by the well-established dental stone mold technology, for reasons of cost and simplicity. PMID:2186936

  12. Prosthetic Rehabilitation of Patients After Surgical Treatment of Maxillary Tumors with Respect to Upper Airway Protection.

    Science.gov (United States)

    Rolski, D; Kostrzewa-Janicka, J; Nieborak, R; Przybyłowska, D; Stopa, Z; Mierzwińska-Nastalska, E

    2016-01-01

    As a consequence of surgical treatment of maxillary tumors, a connection between oral and nasal cavities is formed, which leads to serious functional disorders, manifested by inability to normally ingest food, proper speech articulation, and to respiratory route disorders and upper airway inflammation. These morphological and functional disorders are intensified by adjunctive radio- or chemotherapy. The aim of this paper is to present different possible methods of rehabilitation, including application of interim obturators and individually planned prosthetic restorations to improve respiratory efficiency in patients after extensive maxillary resections. In the course of prosthetic treatment, cooperation with the laryngologist to consider every aspect of chronic paranasal sinusitis, accompanied by concurrent inflammation of oral, nasal, or laryngeal mucous membranes, was of paramount importance. Based on the quality of life questionnaire, used in this study, evident improvement in the masticatory efficiency, speech articulation, and respiration was observed. Particularly good effects were obtained in edentulous patients, in whom implant-prosthetic treatment was possible to apply. Comprehensive and multidisciplinary care of postoperative patients greatly contributes to their better quality of life and facilitates their return to prior living conditions, as well as to occupational and family lives. PMID:26820729

  13. Secure Microprocessor-Controlled Prosthetic Leg for Elderly Amputees: Preliminary Results

    Directory of Open Access Journals (Sweden)

    S. Krut

    2011-01-01

    Full Text Available We introduce a new prosthetic leg design, adapted to elderly trans-femoral amputees. Technical progress in prosthesis design mainly concerns active individuals. An important number of elderly amputees are not very mobile, tire easily, present reduced muscle strength, and have difficulties managing their balance. Therefore, the needs and characteristics of this specific population are very different from those of younger ones and the prosthetic solutions are not adapted. Our artificial knee has been designed to fulfill the specific requirements of this population in terms of capabilities, transfer assistance, security, intuitiveness, simplicity of use, and types of physical activity to be performed. We particularly focused our efforts on ensuring safe and secure stand-to-sit transfers. We developed an approach to control the different states of the prosthetic joint (blocked, free, resistant, associated with different physical activities. Amputee posture and motion are observed through a single multi-axis force sensor embedded in the prosthesis. The patient behaves naturally, while the controller analyses his movements in order to detect his intention to sit down. The detection algorithm is based on a reference pattern, calibrated individually, to which the sensor data are compared, and submitted to a set of tests allowing the discrimination of the intention to sit down from other activities. Preliminary validation of the system has been performed in order to verify the applicability of the prosthesis to different tasks: walking, standing, sitting down, standing up, picking up an object from a chair, slope and stair climbing.

  14. Fabrication techniques and applications of flexible graphene-based electronic devices

    Science.gov (United States)

    Luqi, Tao; Danyang, Wang; Song, Jiang; Ying, Liu; Qianyi, Xie; He, Tian; Ningqin, Deng; Xuefeng, Wang; Yi, Yang; Tian-Ling, Ren

    2016-04-01

    In recent years, flexible electronic devices have become a hot topic of scientific research. These flexible devices are the basis of flexible circuits, flexible batteries, flexible displays and electronic skins. Graphene-based materials are very promising for flexible electronic devices, due to their high mobility, high elasticity, a tunable band gap, quantum electronic transport and high mechanical strength. In this article, we review the recent progress of the fabrication process and the applications of graphene-based electronic devices, including thermal acoustic devices, thermal rectifiers, graphene-based nanogenerators, pressure sensors and graphene-based light-emitting diodes. In summary, although there are still a lot of challenges needing to be solved, graphene-based materials are very promising for various flexible device applications in the future. Project supported by the National Natural Science Foundation of China (Nos. 60936002, 61025021, 61434001, 61574083), the State Key Development Program for Basic Research of China (No. 2015CB352100), the National Key Project of Science and Technology (No. 2011ZX02403-002) and the Special Fund for Agroscientific Research in the Public Interest of China (No. 201303107). M.A.M is additionally supported by the Postdoctoral Fellowship (PDF) Program of the Natural Sciences and Engineering Research Council (NSERC) of Canada and China's Postdoctoral Science Foundation (CPSF).

  15. Low-cost rapid prototyping of flexible plastic paper based microfluidic devices

    KAUST Repository

    Fan, Yiqiang

    2013-04-01

    This research presents a novel rapid prototyping method for paper-based flexible microfluidic devices. The microchannels were fabricated using laser ablation on a piece of plastic paper (permanent paper), the dimensions of the microchannels was carefully studied for various laser powers and scanning speeds. After laser ablation of the microchannels on the plastic paper, a transparent poly (methyl methacrylate)(PMMA) film was thermally bonded to the plastic paper to enclose the channels. After connection of tubing, the device was ready to use. An example microfluidic device (droplet generator) was also fabricated using this technique. Due to the flexibility of the fabricated device, this technique can be used to fabricate 3D microfluidic devices. The fabrication process was simple and rapid without any requirement of cleanroom facilities. © 2013 IEEE.

  16. Inverse design-based metamaterial transparent device and its multilayer realization

    International Nuclear Information System (INIS)

    We propose an inverse method to determine the material parameters of a transparent device without any knowledge of the corresponding transformation function. The required parameters are independently obtained and expressed as functions of the introduced generator. Moreover, to remove the inhomogeneity and anisotropy of material parameters, a layered transparent device composed of only homogeneous and isotropic materials is presented based on the effective medium theory. The feasibility of using the layered device in antenna protection is also investigated. Full-wave simulation is carried out for verification. This work paves a new way toward designing metamaterial devices without specifying the underlying coordinate transformation, and has great guiding significance for the practical fabrication of transparent devices. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  17. Inverse design-based metamaterial transparent device and its multilayer realization

    Science.gov (United States)

    Li, Ting-Hua; Huang, Ming; Yang, Jing-Jing; Yuan, Gang; Cai, Guang-Hui

    2014-05-01

    We propose an inverse method to determine the material parameters of a transparent device without any knowledge of the corresponding transformation function. The required parameters are independently obtained and expressed as functions of the introduced generator. Moreover, to remove the inhomogeneity and anisotropy of material parameters, a layered transparent device composed of only homogeneous and isotropic materials is presented based on the effective medium theory. The feasibility of using the layered device in antenna protection is also investigated. Full-wave simulation is carried out for verification. This work paves a new way toward designing metamaterial devices without specifying the underlying coordinate transformation, and has great guiding significance for the practical fabrication of transparent devices.

  18. Dielectric Coating Thermal Stabilization During GaAs-Based Laser Fabrication for Improved Device Yield

    Science.gov (United States)

    Connors, Michael K.; Millsapp, Jamal E.; Turner, George W.

    2016-03-01

    The quality and yield of GaAs-based ridge waveguide devices fabricated at MIT Lincoln Laboratory were negatively impacted by the random lot-to-lot appearance of blisters in the front-side contact metal. The blisters signaled compromised adhesion between the front-side contact metal, underlying SiO2 dielectric coating, and semiconductor surface. A thermal-anneal procedure developed for the fabrication of GaAs slab coupled optical waveguide (SCOW) ridge waveguide devices stabilizes the SiO2 dielectric coating by means of outgassing and stress reduction. This process eliminates a primary source of adhesion loss, as well as blister generation, and thereby significantly improves device yield. Stoney's equation was used to analyze stress-induced bow in device wafers fabricated using this stabilization procedure. This analysis suggests that changes in wafer bow contribute to the incidence of metal blisters in SCOW devices.

  19. Efficient light-emitting devices based on platinum-complexes-anchored polyhedral oligomeric silsesquioxane materials

    KAUST Repository

    Yang, Xiaohui

    2010-08-24

    The synthesis, photophysical, and electrochemical characterization of macromolecules, consisting of an emissive platinum complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core, is reported. Organic light-emitting devices based on these POSS materials exhibit a peak external quantum efficiency of ca. 8%, which is significantly higher than that of the analogous devices with a physical blend of the platinum complexes and a polymer matrix, and they represent noticeable improvement in the device efficiency of solution-processable phosphorescent excimer devices. Furthermore, the ratio of monomer and excimer/aggregate electroluminescent emission intensity, as well as the device efficiency, increases as the platinum complex moiety presence on the POSS macromolecules decreases. © 2010 American Chemical Society.

  20. The Role of Fast Carrier Dynamics in SOA Based Devices

    DEFF Research Database (Denmark)

    Mørk, Jesper; Berg, Tommy Winther; Nielsen, Mads Lønstrup;

    2004-01-01

    We describe the characteristics of all-optical switching schemes based on semiconductor optical amplifiers (SOAs), with particular emphasis on the role of the fast carrier dynamics. The SOA response to a single short pulse as well as to a data-modulated pulse train is investigated and the propert...

  1. Data base management system configuration specification. [computer storage devices

    Science.gov (United States)

    Neiers, J. W.

    1979-01-01

    The functional requirements and the configuration of the data base management system are described. Techniques and technology which will enable more efficient and timely transfer of useful data from the sensor to the user, extraction of information by the user, and exchange of information among the users are demonstrated.

  2. Studies on GaN-based laser devices make progress

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ A research team led by YANG Hui and CHEN Lianghui with the CAS Institute of Semiconductors (ISCAS) has made breakthrough progress in addressing key technological problems for the GaN-based laser diodes development. The research results were spoken highly at a panel meeting of experts held on 26 November, 2007 in Beijing.

  3. Is seniority-based pay used as a motivation device? Evidence from plant level data

    OpenAIRE

    Bayo-Moriones, Alberto; Galdon-Sanchez, José Enrique; Güell, Maia

    2004-01-01

    In this paper we use data from industrial plants to investigate if seniority-based pay is used as a motivational device for production workers. Alternatively, seniority-based pay could simply be a wage setting rule not necessarily related to the provision of incentives. Unlike previous papers, we use a direct measure of seniority-based pay as well as measures of monitoring devices and piece-rates. We find that firms that offer seniority-based pay are less likely to offer explicit incentives. ...

  4. Quiz Lounge Game-Based Learning on Mobile Devices

    Directory of Open Access Journals (Sweden)

    Bettina Harriehausen-Mühlbauer

    2013-08-01

    Full Text Available The Quiz Lounge project is a collaboration between Hochschule Darmstadt and Lufthansa AG. The goal of the project was the development of a mobile learning application. With the application, the Lufthansa managers should be able to learn about data privacy topics playfully and interactively. The application is based on a quiz concept and asks the user for answers to a series of ten questions which increase in difficulty level. While playing the game the user can use two "lifeline" helpers, the audience- and the 50-50-helper. Furthermore, the user has the ability to browse a glossary of related terms if he or she has the need of more detailed knowledge. New questions and also new games can be added with a web-based authoring tool. The authoring tool was uniquely developed for the Quiz Lounge application and conforms to the specific needs of its architecture.

  5. Stackelberg Game Based Power Allocation for Physical Layer Security of Device-to-device Communication Underlaying Cellular Networks

    Science.gov (United States)

    Qu, Junyue; Cai, Yueming; Wu, Dan; Chen, Hualiang

    2014-05-01

    The problem of power allocation for device-to-device (D2D) underlay communication to improve physical layer security is addressed. Specifically, to improve the secure communication of the cellular users, we introduce a Stackelberg game for allocating the power of the D2D link under a total power constraint and a rate constraint at the D2D pair. In the introduced Stackelberg game the D2D pair works as a seller and the cellular UEs work as buyers. Firstly, because the interference signals from D2D pair are unknown to both the legitimate receiver and the illegitimate eavesdropper, it is possible that a cellular UE decline to participate in the introduced Stackelberg game. So the condition under which a legitimate user will participate in the introduced Stackelberg game is discussed. Then, based on the Stackelberg game, we propose a semi-distributed power allocation algorithm, which is proved to conclude after finite-time iterations. In the end, some simulations are presented to verify the performance improvement in the physical layer security of cellular UEs using the proposed power allocation algorithm. We can determine that with the proposed algorithm, while the D2D pair's communication demand is met, the physical layer security of cellular UEs can be improved.

  6. Novel optical devices based on the tunable refractive index of magnetic fluid and their characteristics

    International Nuclear Information System (INIS)

    As a new type of functional material, magnetic fluid (MF) is a stable colloid of magnetic nanoparticles, dressed with surfactant and dispersed in the carrier liquid uniformly. The MF has many unique optical properties, and the most important one is its tunable refractive index property. This paper summarizes the properties of the MF refractive index and the related optical devices. The refractive index can be easily controlled by external magnetic field, temperature, and so on. But the tunable refractive index of MF has a relaxation effect. As a result, the response time is more than milliseconds and the MF is only suitable for low speed environment. Compared with the traditional optical devices, the magnetic fluid based optical devices have the tuning ability. Compared with the tunable optical devices (the electro-optic devices (LiNbO3) of more than 10 GHz modulation speed, acoustic-optic devices (Ge) of more than 20 MHz modulation speed), the speed of the magnetic fluid based optical devices is low. Now there are many applications of magnetic fluid based on the refractive index in the field of optical information communication and sensing technology, such as tunable beam splitter, optical-fiber modulator, tunable optical gratings, tunable optical filter, optical logic device, tunable interferometer, and electromagnetic sensor. With the development of the research and application of magnetic fluid,a new method, structure and material to improve the response time can be found, which will play an important role in the fields of optical information communication and sensing technology. - Highlights: → Magnetic fluid is a new type of functional material, which has many unique optical properties. → We summarize the tunable refractive index property and the related optical devices. → Refractive index can be easily controlled by external magnetic field, temperature and so on. → There are many applications in the field of optical communication and sensing

  7. Novel optical devices based on the transmission properties of magnetic fluid and their characteristics

    Science.gov (United States)

    Zhao, Yong; Lv, Riqing; Zhang, Yuyan; Wang, Qi

    2012-09-01

    Magnetic fluid has many unique optical properties. It has numerous potential applications in developing optical devices because of its versatile optical properties. This paper summarizes the physical origins and control mechanisms of the MF transmission properties, and the related optical devices based on the transmission properties of magnetic fluid. In recent years, there are many applications in optical information communication and sensing technology, such as optical switches, tunable optical gratings, coarse wavelength-division multiplexing, magnetic-field sensors, current sensor. The qualitative and quantitative analysis about the physical configuration, the operating principle, and the characteristics of those optical devices are given. The valuable potential problems and the solutions that are related to optical properties and optical devices based on magnetic fluid are expounded in detail, and potential new types of MF-based optical devices are proposed. It can be concluded that the transmission properties of MF will be improved greatly, and the characteristics of present optical devices based on magnetic fluid will be made better continually and it will play an important role in the fields of optical information communication and sensing technology.

  8. Frequency response of a focused SAW device based on concentric wave surfaces: simulation and experiment

    Science.gov (United States)

    Wu, Tsung-Tsong; Tang, He-Tai; Chen, Yung-Yu

    2005-08-01

    Focused interdigital transducers (FIDTs) based on concentric wave surfaces can excite surface acoustic wave (SAW) with high intensity, high beamwidth compression ratio and small localized area. In this paper, we developed a model to analyse the frequency response of a SAW device with FIDTs based on concentric wave surfaces. First, we constructed a focused SAW device by adopting a pair of FIDTs shaped as the concentric wave surface. To calculate its frequency response, a simulation model was established based on the 2D SAW filter model, effective permittivity approach and perturbation theory. Further, the focused SAW devices were designed and fabricated via the microelectromechanical system process technique. A good agreement between the simulated and measured results was found. Finally, the frequency responses of focused SAW devices based on concentric wave surfaces were discussed and some attractive features were found, such as less ripples of pass-band and high stop-band rejection. In addition, in comparison with the conventional SAW devices with uniform interdigital transducers, the focused SAW devices are more sensitive to variations in the focal area, instead of the whole delayline region. Accordingly, they are suitable to be applied to detect or manipulate some localized variations, such as acousto-optic or acousto-electric effects.

  9. Pre-Prosthetic surgical alterations in maxillectomy to enhance the prosthetic prognoses as part of rehabilitation of oral cancer patient

    Science.gov (United States)

    El Fattah, Hisham; Zaghloul, Ashraf; Escuin, Tomas

    2012-01-01

    Objectives: After maxillectomy, prosthetic restoration of the resulting defect is an essential step because it signals the beginning of patient’s rehabilitation. The obturator used to restore the defect should be comfortable, restore adequate speech, deglutition, mastication, and be cosmetically acceptable, success will depend on the size and location of the defect and the quantity and integrity of the remaining structures, in addition to pre-prosthetic surgical preparation of defect site. Preoperative cooperation between the oncologist surgeon and the maxillofacial surgeon may allow obturation of a resultant defect by preservation of the premaxilla or the tuberosity on the defect side and maintaining the alveolar bone or teeth adjacent to the defect. This study evaluates the importance of pre-prosthetic surgical alterations at the time maxillectomy on the enhancement of the prosthetic prognoses as part of the rehabilitation of oral cancer patient. Study Design: The study was carried out between 2003- 2008, on 66 cancer patients(41 male-25 female) age ranged from 33 to 72 years, at National Cancer Institute, Cairo University, whom underwent maxillectomy surgery to remove malignant tumor as a part of cancer treatment. Patients were divided in two groups. Group A: Resection of maxilla followed by preprosthetic surgical preparation. Twenty-four cancer patients (13 male – 11 female). Group B: Resection of maxilla without any preprosthetic surgical preparation. Forty-two cancer patients (28 male-14 female). Results: Outcome variables measured included facial contour and aesthetic results, speech understandability, ability to eat solid foods, oronasal separation, socializing outside the home, and return-to-work status. Flap success and donor site morbidity were also studied. Conclusions: To improve the prosthetic restoration of maxillary defect resulting maxillary resection as part treatment of maxillofacial tumor depends on the close cooperation between

  10. Non-volatile resistive memory devices based on solution-processed ultrathin two-dimensional nanomaterials.

    Science.gov (United States)

    Tan, Chaoliang; Liu, Zhengdong; Huang, Wei; Zhang, Hua

    2015-05-01

    Ultrathin two-dimensional (2D) nanomaterials, such as graphene and MoS2, hold great promise for electronics and optoelectronics due to their distinctive physical and electronic properties. Recent progress in high-yield, massive production of ultrathin 2D nanomaterials via various solution-based methods allows them to be easily integrated into electronic devices via solution processing techniques. Non-volatile resistive memory devices based on ultrathin 2D nanomaterials have been emerging as promising alternatives for the next-generation data storage devices due to their high flexibility, three-dimensional-stacking capability, simple structure, transparency, easy fabrication and low cost. In this tutorial review, we will summarize the recent progress in the utilization of solution-processed ultrathin 2D nanomaterials for fabrication of non-volatile resistive memory devices. Moreover, we demonstrate how to achieve excellent device performance by engineering the active layers, electrodes and/or device structure of resistive memory devices. On the basis of current status, the discussion is concluded with some personal insights into the challenges and opportunities in future research directions. PMID:25877687

  11. A magnetorheological fluid-based multifunctional haptic device for vehicular instrument controls

    International Nuclear Information System (INIS)

    This paper presents control performances of a magnetorheological (MR) fluid-based multifunctional haptic device which is applicable to vehicular instrument controls. By combining in-vehicle functions into a single device, the proposed haptic device can transmit various reflection forces for each comfort function to a driver without requiring the driver's visual attention. As a multifunctional haptic device, a MR knob is proposed in this work and then devised to be capable of both rotary and push motions with a single knob. Under consideration of the spatial limitations of vehicle dashboards, design parameters are optimally determined by finite element analysis, and the objective function is to maximize a relative control torque. The proposed haptic device is then manufactured, and in-vehicle comfort functions are constructed in a virtual environment which makes the functions to communicate with the haptic device. Subsequently, a feed-forward controller using torque/force maps is formulated for the force tracking control. Control performances such as reflection force of the haptic device are experimentally evaluated via the torque/force map-based feed-forward controller

  12. Validating the Accuracy of Reaction Time Assessment on Computer-Based Tablet Devices.

    Science.gov (United States)

    Schatz, Philip; Ybarra, Vincent; Leitner, Donald

    2015-08-01

    Computer-based assessment has evolved to tablet-based devices. Despite the availability of tablets and "apps," there is limited research validating their use. We documented timing delays between stimulus presentation and (simulated) touch response on iOS devices (3rd- and 4th-generation Apple iPads) and Android devices (Kindle Fire, Google Nexus, Samsung Galaxy) at response intervals of 100, 250, 500, and 1,000 milliseconds (ms). Results showed significantly greater timing error on Google Nexus and Samsung tablets (81-97 ms), than Kindle Fire and Apple iPads (27-33 ms). Within Apple devices, iOS 7 obtained significantly lower timing error than iOS 6. Simple reaction time (RT) trials (250 ms) on tablet devices represent 12% to 40% error (30-100 ms), depending on the device, which decreases considerably for choice RT trials (3-5% error at 1,000 ms). Results raise implications for using the same device for serial clinical assessment of RT using tablets, as well as the need for calibration of software and hardware. PMID:25612627

  13. Pannus-related prosthetic valve dysfunction. Case report

    Science.gov (United States)

    MOLDOVAN, MARIA-SÎNZIANA; BEDELEANU, DANIELA; KOVACS, EMESE; CIUMĂRNEAN, LORENA; MOLNAR, ADRIAN

    2016-01-01

    Pannus-related prosthetic valve dysfunction, a complication of mechanical prosthetic valve replacement, is rare, with a slowly progressive evolution, but it can be acute, severe, requiring surgical reintervention. We present the case of a patient with a mechanical single disc aortic prosthesis, with moderate prosthesis-patient mismatch, minor pannus found on previous ultrasound examinations, who presented to our service with angina pain with a duration of 1 hour, subsequently interpreted as non-ST segment elevation myocardial infarction (NSTEMI) syndrome. Coronarography showed normal epicardial coronary arteries, an ample movement of the prosthetic disc, without evidence of coronary thromboembolism, and Gated Single-Photon Emission Computerized Tomography (SPECT) with Technetium (Tc)-99m detected no perfusion defects. Transthoracic echocardiography (TTE) evidenced a dysfunctional prosthesis due to a subvalvular mass; transesophageal echocardiography (TOE) showed the interference of this mass, with a pannus appearance, with the closure of the prosthetic disc. Under conditions of repeated angina episodes, under anticoagulant treatment, surgery was performed, with the intraoperative confirmation of pannus and its removal. Postoperative evolution was favorable. This case reflects the diagnostic and therapeutic management problems of pannus-related prosthetic valve dysfunction. PMID:27004041

  14. A Pull-in Based Test Mechanism for Device Diagnostic and Process Characterization

    Directory of Open Access Journals (Sweden)

    L. A. Rocha

    2008-01-01

    Full Text Available A test technique for capacitive MEMS accelerometers and electrostatic microactuators, based on the measurement of pull-in voltages and resonance frequency, is described. Using this combination of measurements, one can estimate process-induced variations in the device layout dimensions as well as deviations from nominal value in material properties, which can be used either for testing or device diagnostics purposes. Measurements performed on fabricated devices confirm that the 250 nm overetch observed on SEM images can be correctly estimated using the proposed technique.

  15. Electrochemical biosensors and logic devices based on aptamers

    Institute of Scientific and Technical Information of China (English)

    Zuo Xiaolei; Lin Meihua; Fan Chunhai

    2013-01-01

    Aptamers are molecular recognition elements with high specificity that are selected from deoxyribonucleic acid/ribonucleic acid (DNA/RNA) library.Compared with the traditional protein recognition elements,aptamers have excellent properties such as cost-effective,stable,easy for synthesis and modification.In recent years,electrochemistry plays an important role in biosensor field because of its high sensitivity,high stability,fast response and easy miniaturization.Through the combination of these two technologies and our rational design,we constructed a series of biosensors and biochips that are simple,fast,cheap and miniaturized.Firstly,we designed an adenosine triphosphate (ATP) electrochemical biosensor based on the strand displacement strategy.We can detect as low as 10 nmol/L of ATP both in pure solution and complicated cell lysates.Secondly,we creatively split the aptamers into two fragments and constructed the sandwich assay platform only based on single aptamer sequence.We successfully transferred this design on biochips with multiple micro electrodes (6×6) and accomplished multiplex detection.In the fields of biochips and biocomputers,we designed several DNA logic gates with electric (electrochemical) signal as output which paves a new way for the development of DNA computer.

  16. A Real time Data Acquisition and Monitoring Device for Medical Applications based on Android Platform

    Directory of Open Access Journals (Sweden)

    Jithin Krishnan

    2013-09-01

    Full Text Available An android based real time data acquisition and monitoring device is presented here. The system finds its initial application in medical field .it serves as a remote monitor for measuring and analysing along with logging of data from patients. The system comprises of two parts. A data acquisition (DaQ part connected to patient side and an android based display device on the receiving end. The Data Acquisition part contains sensors for picking up the vital signs from the patients, signal conditioning circuits and a Bluetooth transceiver to transmit data wirelessly to the display device. The Display Device then displays the data received from the transmitter in a readable form and also logs the data into a excel form so that it can be taken out digitally and analysed.

  17. Bipolar resistive switching characteristics in tantalum nitride-based resistive random access memory devices

    Science.gov (United States)

    Kim, Myung Ju; Jeon, Dong Su; Park, Ju Hyun; Kim, Tae Geun

    2015-05-01

    This paper reports the bipolar resistive switching characteristics of TaNx-based resistive random access memory (ReRAM). The conduction mechanism is explained by formation and rupture of conductive filaments caused by migration of nitrogen ions and vacancies; this mechanism is in good agreement with either Ohmic conduction or the Poole-Frenkel emission model. The devices exhibit that the reset voltage varies from -0.82 V to -0.62 V, whereas the set voltage ranges from 1.01 V to 1.30 V for 120 DC sweep cycles. In terms of reliability, the devices exhibit good retention (>105 s) and pulse-switching endurance (>106 cycles) properties. These results indicate that TaNx-based ReRAM devices have a potential for future nonvolatile memory devices.

  18. Bipolar resistive switching characteristics in tantalum nitride-based resistive random access memory devices

    International Nuclear Information System (INIS)

    This paper reports the bipolar resistive switching characteristics of TaNx-based resistive random access memory (ReRAM). The conduction mechanism is explained by formation and rupture of conductive filaments caused by migration of nitrogen ions and vacancies; this mechanism is in good agreement with either Ohmic conduction or the Poole-Frenkel emission model. The devices exhibit that the reset voltage varies from −0.82 V to −0.62 V, whereas the set voltage ranges from 1.01 V to 1.30 V for 120 DC sweep cycles. In terms of reliability, the devices exhibit good retention (>105 s) and pulse-switching endurance (>106 cycles) properties. These results indicate that TaNx-based ReRAM devices have a potential for future nonvolatile memory devices

  19. Bipolar resistive switching characteristics in tantalum nitride-based resistive random access memory devices

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Ju; Jeon, Dong Su; Park, Ju Hyun; Kim, Tae Geun, E-mail: tgkim1@korea.ac.kr [School of Electrical Engineering, Anam-dong 5ga, Sungbuk-gu, Seoul 136-701 (Korea, Republic of)

    2015-05-18

    This paper reports the bipolar resistive switching characteristics of TaN{sub x}-based resistive random access memory (ReRAM). The conduction mechanism is explained by formation and rupture of conductive filaments caused by migration of nitrogen ions and vacancies; this mechanism is in good agreement with either Ohmic conduction or the Poole-Frenkel emission model. The devices exhibit that the reset voltage varies from −0.82 V to −0.62 V, whereas the set voltage ranges from 1.01 V to 1.30 V for 120 DC sweep cycles. In terms of reliability, the devices exhibit good retention (>10{sup 5 }s) and pulse-switching endurance (>10{sup 6} cycles) properties. These results indicate that TaN{sub x}-based ReRAM devices have a potential for future nonvolatile memory devices.

  20. High Resolution Tracking Devices Based on Capillaries Filled with Liquid Scintillator

    CERN Multimedia

    Bonekamper, D; Vassiltchenko, V; Wolff, T

    2002-01-01

    %RD46 %title\\\\ \\\\The aim of the project is to develop high resolution tracking devices based on thin glass capillary arrays filled with liquid scintillator. This technique provides high hit densities and a position resolution better than 20 $\\mu$m. Further, their radiation hardness makes them superior to other types of tracking devices with comparable performance. Therefore, the technique is attractive for inner tracking in collider experiments, microvertex devices, or active targets for short-lived particle detection. High integration levels in the read-out based on the use of multi-pixel photon detectors and the possibility of optical multiplexing allow to reduce considerably the number of output channels, and, thus, the cost for the detector.\\\\ \\\\New optoelectronic devices have been developed and tested: the megapixel Electron Bombarded CCD (EBCCD), a high resolution image-detector having an outstanding capability of single photo-electron detection; the Vacuum Image Pipeline (VIP), a high-speed gateable pi...

  1. Design, development and implementation of a PC-Based programmable peripheral I/O devices trainer

    International Nuclear Information System (INIS)

    The miracle chip microprocessor represents a quantum leap in the technology of mankind, a development that over the past decade has acquired the significance in industrial automation and has led PCs to become workhorses in the everyday industrial environment. The communication of Microprocessor to the outside world depends upon the I/O devices and Interfacing Techniques. This work deals with the technique of interfacing Intel, Motorola, and Zilog processors, with their respective I/O devices (PPI, PIA, and PIO) for parallel data transfer. The PC based trainer is specifically designed to demonstrate how a particular microprocessor selects and initializes an I/O device, what hardware chips are necessary, what software instructions are used, and how various data transfers take place. Many practical exercises can be developed in software to expose students to more complex applications using PC-based Programmable Peripheral I/O Devices Trainer. (author)

  2. PROTEOTRONICS: The emerging science of protein-based electronic devices

    Science.gov (United States)

    Alfinito, Eleonora; Pousset, Jeremy; Reggiani, Lino

    2015-10-01

    Protein-mediated charge transport is of relevant importance in the design of protein based electronics and in attaining an adequate level of understanding of protein functioning. This is particularly true for the case of transmembrane proteins, like those pertaining to the G protein coupled receptors (GPCRs). These proteins are involved in a broad range of biological processes like catalysis, substance transport, etc., thus being the target of a large number of clinically used drugs. This paper briefly reviews a variety of experiments devoted to investigate charge transport in proteins and present a unified theoretical model able to relate macroscopic experimental results with the conformations of the amino acids backbone of the single protein.

  3. Experimental Study on Neutron Radiography Device Based on Reactor

    Institute of Scientific and Technical Information of China (English)

    LU; Jin; PENG; Dan; HAO; Qian; YU; Bo-xiang; LI; Yi-guo

    2012-01-01

    <正>Neutron radiography is a non-destructive testing developing fast recently, which requires stable and proper neutron source with low γ background. Neutrons from In-hospital Neutron Irradiator (IHNI) could meet this requirement. Based on the neutron beams of IHNI, a collimator is designed and built for neutron radiography. The experiment results show that in the case of IHNI working at normal rated power, the neutron flux at the end of the collimator is 1.43×106 cm-2·s-1; The max collimation ratio (L/D) is 58; the γ dose rate is 6.3×106 mSv/s. In a word, the collimator could be used for neutron radiography.

  4. Scintillation gas detector based on a charge coupled device

    International Nuclear Information System (INIS)

    A new imaging X-ray detector able to copy with the high photon flux of ESRF X-ray sources has been proposed. The detector has been based on scintillation gas chamber, which converts X-ray photon with a wavelength of 1.54 Angstrom in U.V. photons, coupled with a CCD, which detects in the position of the U.V. photons with wavelength greater than 1800 Angstrom. Using this detector, saturation effects due to the spatial charge of the avalanche discharge in the gas and radiation damage on the CCD, have been eliminated. A conical optical fibre system, collecting the U.V. photon flashes on CCD, magnyfying the detecting area of detector and allowing to obtain spatial resolution better than 0.3 mm, is suggested

  5. Cloud-Based Augmentation for Mobile Devices: Motivation, Taxonomies, and Open Challenges

    OpenAIRE

    Abolfazli, Saeid; Sanaei, Zohreh; Ahmed, Ejaz; Gani, Abdullah; Buyya, Rajkumar

    2013-01-01

    Recently, Cloud-based Mobile Augmentation (CMA) approaches have gained remarkable ground from academia and industry. CMA is the state-of-the-art mobile augmentation model that employs resource-rich clouds to increase, enhance, and optimize computing capabilities of mobile devices aiming at execution of resource-intensive mobile applications. Augmented mobile devices envision to perform extensive computations and to store big data beyond their intrinsic capabilities with least footprint and vu...

  6. Memory impedance in TiO2 based metal-insulator-metal devices

    OpenAIRE

    Li Qingjiang; Ali Khiat; Iulia Salaoru; Christos Papavassiliou; Xu Hui; Themistoklis Prodromakis

    2014-01-01

    Large attention has recently been given to a novel technology named memristor, for having the potential of becoming the new electronic device standard. Yet, its manifestation as the fourth missing element is rather controversial among scientists. Here we demonstrate that TiO2-based metal-insulator-metal devices are more than just a memory-resistor. They possess resistive, capacitive and inductive components that can concurrently be programmed; essentially exhibiting a convolution of memristiv...

  7. On the Feasibility of Attribute-Based Encryption on Smartphone Devices

    OpenAIRE

    Ambrosin, Moreno; Conti, Mauro; Dargahi, Tooska

    2015-01-01

    Attribute-Based Encryption (ABE) is a powerful cryptographic tool that allows fine-grained access control over data. Due to its features, ABE has been adopted in several applications, such as encrypted storage or access control systems. Recently, researchers argued about the non acceptable performance of ABE when implemented on mobile devices. Indeed, the non feasibility of ABE on mobile devices would hinder the deployment of novel protocols and services--that could instead exploit the full p...

  8. Use of plastic-based analytical device, smartphone and chemometric tools to discriminate amines

    OpenAIRE

    Reddy, SM; Bueno, L.; Meloni, G; Paixao, TRLC

    2015-01-01

    Amine-based volatile compounds released bymicroorganisms offer an alternative diagnostic approach for the identification of foodborne pathogens. Our objective has been to solvent cast cellulose acetate membranes to immobilise dyes and to use the resultant membranes as a plastic device to discriminate between different types of amines (triethylamine, isobutylamine, isopentylamine). The plastic device consisted of an array of membranes with five pH indicators (namely alizarin, bromophenol blue,...

  9. Probabilistic Multi-Sensor Fusion Based Indoor Positioning System on a Mobile Device

    OpenAIRE

    Xiang He; Aloi, Daniel N.; Jia Li

    2015-01-01

    Nowadays, smart mobile devices include more and more sensors on board, such as motion sensors (accelerometer, gyroscope, magnetometer), wireless signal strength indicators (WiFi, Bluetooth, Zigbee), and visual sensors (LiDAR, camera). People have developed various indoor positioning techniques based on these sensors. In this paper, the probabilistic fusion of multiple sensors is investigated in a hidden Markov model (HMM) framework for mobile-device user-positioning. We propose a graph struct...

  10. Intelligent Security Auditing Based on Access Control of Devices in Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    XU Guang-wei; SHI You-qun; ZHU Ming; WU Guo-wen; CAO Qi-ying

    2006-01-01

    Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy and operating regulation and used to identify abnormal operation. Model of security auditing based on access control of devices will be advanced to register sign of devices and property of event of access control and to audit those actions. In the end, the model is analyzed and simulated.

  11. Estimating the revenues of a hydrogen-based high-capacity storage device: methodology and results

    OpenAIRE

    François-Lavet, Vincent; Fonteneau, Raphaël; Ernst, Damien

    2014-01-01

    This paper proposes a methodology to estimate the maximum revenue that can be generated by a company that operates a high-capacity storage device to buy or sell electricity on the day-ahead electricity market. The methodology exploits the Dynamic Programming (DP) principle and is specified for hydrogen-based storage devices that use electrolysis to produce hydrogen and fuel cells to generate electricity from hydrogen. Experimental results are generated using historical data of energy prices o...

  12. PANATIKI: A Network Access Control Implementation Based on PANA for IoT Devices

    OpenAIRE

    Antonio F. Gomez Skarmeta; Rafa Marin Lopez; Pedro Moreno Sanchez

    2013-01-01

    Internet of Things (IoT) networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP)-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data) or access network services. However, only authenticated and a...

  13. Web Services Based Learning Objects Generator for Device-Independent M-Learning

    OpenAIRE

    Akram Moh. Alkouz

    2006-01-01

    Learning objects, which are the base component of m-learning system, are usually target to modifications in contexts and formats. The device- dependent applications of hand-held devices have proven to be ineffective for creating m-learning courseware. Learning Objects Metadata (LOM) is the most popular standard specification for learning objects but lacks the ability to facilitate platforms descriptions. This paper outlines various aspects of design and implementation of Web Services Oriente...

  14. Development of low-cost sensing and separation devices based on macro, micro and nano technology for health applications

    OpenAIRE

    Crowley, Una Bernadette

    2014-01-01

    The work presented in this thesis described the development of low-cost sensing and separation devices with electrochemical detections for health applications. This research employs macro, micro and nano technology. The first sensing device developed was a tonerbased micro-device. The initial development of microfluidic devices was based on glass or quartz devices that are often expensive to fabricate; however, the introduction of new types of materials, such as plastics, offered a new way fo...

  15. Unconventional supercapacitors from nanocarbon-based electrode materials to device configurations.

    Science.gov (United States)

    Liu, Lili; Niu, Zhiqiang; Chen, Jun

    2016-07-25

    As energy storage devices, supercapacitors that are also called electrochemical capacitors possess high power density, excellent reversibility and long cycle life. The recent boom in electronic devices with different functions in transparent LED displays, stretchable electronic systems and artificial skin has increased the demand for supercapacitors to move towards light, thin, integrated macro- and micro-devices with transparent, flexible, stretchable, compressible and/or wearable abilities. The successful fabrication of such supercapacitors depends mainly on the preparation of innovative electrode materials and the design of unconventional supercapacitor configurations. Tremendous research efforts have been recently made to design and construct innovative nanocarbon-based electrode materials and supercapacitors with unconventional configurations. We review here recent developments in supercapacitors from nanocarbon-based electrode materials to device configurations. The advances in nanocarbon-based electrode materials mainly include the assembly technologies of macroscopic nanostructured electrodes with different dimensions of carbon nanotubes/nanofibers, graphene, mesoporous carbon, activated carbon, and their composites. The electrodes with macroscopic nanostructured carbon-based materials overcome the issues of low conductivity, poor mechanical properties, and limited dimensions that are faced by conventional methods. The configurational design of advanced supercapacitor devices is presented with six types of unconventional supercapacitor devices: flexible, micro-, stretchable, compressible, transparent and fiber supercapacitors. Such supercapacitors display unique configurations and excellent electrochemical performance at different states such as bending, stretching, compressing and/or folding. For example, all-solid-state simplified supercapacitors that are based on nanostructured graphene composite paper are able to maintain 95% of the original capacity at

  16. Microchip-based electrochemical detection using a 3-D printed wall-jet electrode device.

    Science.gov (United States)

    Munshi, Akash S; Martin, R Scott

    2016-02-01

    Three dimensional (3-D) printing technology has evolved dramatically in the last few years, offering the capability of printing objects with a variety of materials. Printing microfluidic devices using this technology offers various advantages such as ease and uniformity of fabrication, file sharing between laboratories, and increased device-to-device reproducibility. One unique aspect of this technology, when used with electrochemical detection, is the ability to produce a microfluidic device as one unit while also allowing the reuse of the device and electrode for multiple analyses. Here we present an alternate electrode configuration for microfluidic devices, a wall-jet electrode (WJE) approach, created by 3-D printing. Using microchip-based flow injection analysis, we compared the WJE design with the conventionally used thin-layer electrode (TLE) design. It was found that the optimized WJE system enhances analytical performance (as compared to the TLE design), with improvements in sensitivity and the limit of detection. Experiments were conducted using two working electrodes - 500 μm platinum and 1 mm glassy carbon. Using the 500 μm platinum electrode the calibration sensitivity was 16 times higher for the WJE device (as compared to the TLE design). In addition, use of the 1 mm glassy carbon electrode led to limit of detection of 500 nM for catechol, as compared to 6 μM for the TLE device. Finally, to demonstrate the versatility and applicability of the 3-D printed WJE approach, the device was used as an inexpensive electrochemical detector for HPLC. The number of theoretical plates was comparable to the use of commercially available UV and MS detectors, with the WJE device being inexpensive to utilize. These results show that 3-D-printing can be a powerful tool to fabricate reusable and integrated microfluidic detectors in configurations that are not easily achieved with more traditional lithographic methods. PMID:26649363

  17. Configurable Resistive Switching between Memory and Threshold Characteristics for Protein-Based Devices

    KAUST Repository

    Wang, Hong

    2015-05-01

    The employ of natural biomaterials as the basic building blocks of electronic devices is of growing interest for biocompatible and green electronics. Here, resistive switching (RS) devices based on naturally silk protein with configurable functionality are demonstrated. The RS type of the devices can be effectively and exactly controlled by controlling the compliance current in the set process. Memory RS can be triggered by a higher compliance current, while threshold RS can be triggered by a lower compliance current. Furthermore, two types of memory devices, working in random access and WORM modes, can be achieved with the RS effect. The results suggest that silk protein possesses the potential for sustainable electronics and data storage. In addition, this finding would provide important guidelines for the performance optimization of biomaterials based memory devices and the study of the underlying mechanism behind the RS effect arising from biomaterials. Resistive switching (RS) devices with configurable functionality based on protein are successfully achieved. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Ubi-RKE: A Rhythm Key Based Encryption Scheme for Ubiquitous Devices

    Directory of Open Access Journals (Sweden)

    Jae Dong Lee

    2014-01-01

    Full Text Available As intelligent ubiquitous devices become more popular, security threats targeting them are increasing; security is seen as one of the major challenges of the ubiquitous computing. Now a days, applying ubiquitous computing in number of fields for human safety and convenience was immensely increased in recent years. The popularity of the technology is rising day by day, and hence the security is becoming the main focused point with the advent and rising popularity of the applications. In particular, the number of wireless networks based on ubiquitous devices has increased rapidly; these devices support transmission for many types of data traffic. The convenient portability of ubiquitous devices makes them vulnerable to security threats, such as loss, theft, data modification, and wiretapping. Developers and users should seriously consider employing data encryption to protect data from such vulnerabilities. In this paper, we propose a Rhythm Key based Encryption scheme for ubiquitous devices (Ubi-RKE. The concept of Rhythm Key based Encryption has been applied to numerous real world applications in different domains. It provides key memorability and secure encryption through user touching rhythm on ubiquitous devices. Our proposed scheme is more efficient for users than existing schemes, by providing a strong cipher.

  19. Multiple functional UV devices based on III-Nitride quantum wells for biological warfare agent detection

    Science.gov (United States)

    Wang, Qin; Savage, Susan; Persson, Sirpa; Noharet, Bertrand; Junique, Stéphane; Andersson, Jan Y.; Liuolia, Vytautas; Marcinkevicius, Saulius

    2009-02-01

    We have demonstrated surface normal detecting/filtering/emitting multiple functional ultraviolet (UV) optoelectronic devices based on InGaN/GaN, InGaN/AlGaN and AlxGa1-xN/AlyGa1-yN multiple quantum well (MQW) structures with operation wavelengths ranging from 270 nm to 450 nm. Utilizing MQW structure as device active layer offers a flexibility to tune its long cut-off wavelength in a wide UV range from solar-blind to visible by adjusting the well width, well composition and barrier height. Similarly, its short cut-off wavelength can be adjusted by using a GaN or AlGaN block layer on a sapphire substrate when the device is illuminated from its backside, which further provides an optical filtering effect. When a current injects into the device under forward bias the device acts as an UV light emitter, whereas the device performs as a typical photodetector under reverse biases. With applying an alternating external bias the device might be used as electroabsorption modulator due to quantum confined Stark effect. In present work fabricated devices have been characterized by transmission/absorption spectra, photoresponsivity, electroluminescence, and photoluminescence measurements under various forward and reverse biases. The piezoelectric effect, alloy broadening and Stokes shift between the emission and absorption spectra in different InGaN- and AlGaN-based QW structures have been investigated and compared. Possibilities of monolithic or hybrid integration using such multiple functional devices for biological warfare agents sensing application have also be discussed.

  20. Nonlinear behaviour of electrostatically actuated carbon nanotube-based devices

    International Nuclear Information System (INIS)

    In this paper nonlinear behaviour of electrostatically actuated carbon nanotubes (CNTs) is investigated. The model comprises a clamped-clamped CNT suspended over a graphite ground electrode plate from which a potential difference is imposed. The actuation is based on ac and dc applied voltages and it is assumed that the neutral axis of bending is stretched when the beam is deflected, and also, the interatomic interaction forces between CNT and ground plate are considered. The versatile Galerkin's method is employed to reduce the nonlinear integral-partial-differential equation of motion to a nonlinear ordinary differential equation in time, and then, the reduced equation is solved by direct numerical integration. In the dc voltage actuation case, the pull-in/pull-out phenomena, hysteresis characteristic, pull-in time duration and the response of the system are studied. The obtained results are compared with the molecular dynamics method. Eventually, a nano-switch immune to input noise is proposed, which relies on the hysteresis characteristic of the system. In combined ac and dc voltage actuations, the vibrational behaviour and nonlinear frequency response of nano-resonator are studied.

  1. Exploration of microfluidic devices based on multi-filament threads and textiles: A review.

    Science.gov (United States)

    Nilghaz, A; Ballerini, D R; Shen, W

    2013-01-01

    In this paper, we review the recent progress in the development of low-cost microfluidic devices based on multifilament threads and textiles for semi-quantitative diagnostic and environmental assays. Hydrophilic multifilament threads are capable of transporting aqueous and non-aqueous fluids via capillary action and possess desirable properties for building fluid transport pathways in microfluidic devices. Thread can be sewn onto various support materials to form fluid transport channels without the need for the patterned hydrophobic barriers essential for paper-based microfluidic devices. Thread can also be used to manufacture fabrics which can be patterned to achieve suitable hydrophilic-hydrophobic contrast, creating hydrophilic channels which allow the control of fluids flow. Furthermore, well established textile patterning methods and combination of hydrophilic and hydrophobic threads can be applied to fabricate low-cost microfluidic devices that meet the low-cost and low-volume requirements. In this paper, we review the current limitations and shortcomings of multifilament thread and textile-based microfluidics, and the research efforts to date on the development of fluid flow control concepts and fabrication methods. We also present a summary of different methods for modelling the fluid capillary flow in microfluidic thread and textile-based systems. Finally, we summarized the published works of thread surface treatment methods and the potential of combining multifilament thread with other materials to construct devices with greater functionality. We believe these will be important research focuses of thread- and textile-based microfluidics in future. PMID:24086179

  2. Surgical-prosthetic treatment of large mandibular cysts

    Directory of Open Access Journals (Sweden)

    Džambas Ljubiša D.

    2003-01-01

    Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

  3. Investigation of frequency-selective devices based on a microstrip 2D photonic crystal

    Science.gov (United States)

    Belyaev, B. A.; Khodenkov, S. A.; Shabanov, V. F.

    2016-04-01

    The frequency-selective properties of structures based on a 2D microstrip photonic crystal have been investigated theoretically and experimentally. It is shown that various microwave devices, including diplexers, bandpass filters, and double bandpass filters, can be designed based on these structures.

  4. GPS-based handheld device for mapping contaminated areas

    International Nuclear Information System (INIS)

    Sometimes one is confronted with the challenge to map large areas with enhanced radioactivity. Examples are mine tailings or waste rock piles, deposits of the phosphate industry, flooding zones contaminated by effluents of plants processing ores containing enhanced natural radiation, nuclear accident sites etc. Car borne measuring equipment is not always an option, as the terrain might be rough and only accessible by foot. Airborne mapping with helicopters on the other hand is fast, but expensive, not readily available, shows difficulties with complex topography and lacks the necessary detail. The objective of this study was to create a portable and easily usable tool for the real time logging of radiation and location data, allowing mapping the radioactivity by simply walking over any kind of terrain with the portable equipment and post processing the data in the office. We also assessed the performance of the GPS based system on contaminated sites with areas varying from less than a hectare to several tens of hectares, with respect to speed, precision and ease of use. At sites of large scale mining and processing of uranium ore, tailings and waste rock piles are today the most visible relics of the uranium extractive industry. These mining relics are constantly subjected to weathering and leaching processes causing the dissemination of radioactive and toxic elements and sometimes requiring remedial operations. The in situ remediation of waste rock piles usually includes their revegetation for minimizing the water infiltration and for increasing surface soil stability. Thanks to its biomass density and longevity, the perennial vegetation plays an important role in stabilisation of the water cycling. The buffer role of forest vegetation can reduce water export from watersheds as well as erosion and hydrological losses of chemicals including radionuclides from contaminated sites. If long term reduction of contaminant dispersion at revegetated uranium mining sites is

  5. Silk-based resorbable electronic devices for remotely controlled therapy and in vivo infection abatement

    Science.gov (United States)

    Tao, Hu; Hwang, Suk-Won; Marelli, Benedetto; An, Bo; Moreau, Jodie E.; Yang, Miaomiao; Brenckle, Mark A.; Kim, Stanley; Kaplan, David L.; Rogers, John A.; Omenetto, Fiorenzo G.

    2014-01-01

    A paradigm shift for implantable medical devices lies at the confluence between regenerative medicine, where materials remodel and integrate in the biological milieu, and technology, through the use of recently developed material platforms based on biomaterials and bioresorbable technologies such as optics and electronics. The union of materials and technology in this context enables a class of biomedical devices that can be optically or electronically functional and yet harmlessly degrade once their use is complete. We present here a fully degradable, remotely controlled, implantable therapeutic device operating in vivo to counter a Staphylococcus aureus infection that disappears once its function is complete. This class of device provides fully resorbable packaging and electronics that can be turned on remotely, after implantation, to provide the necessary thermal therapy or trigger drug delivery. Such externally controllable, resorbable devices not only obviate the need for secondary surgeries and retrieval, but also have extended utility as therapeutic devices that can be left behind at a surgical or suturing site, following intervention, and can be externally controlled to allow for infection management by either thermal treatment or by remote triggering of drug release when there is retardation of antibiotic diffusion, deep infections are present, or when systemic antibiotic treatment alone is insufficient due to the emergence of antibiotic-resistant strains. After completion of function, the device is safely resorbed into the body, within a programmable period. PMID:25422476

  6. Development of fluorescence based handheld imaging devices for food safety inspection

    Science.gov (United States)

    Lee, Hoyoung; Kim, Moon S.; Chao, Kuanglin; Lefcourt, Alan M.; Chan, Diane E.

    2013-05-01

    For sanitation inspection in food processing environment, fluorescence imaging can be a very useful method because many organic materials reveal unique fluorescence emissions when excited by UV or violet radiation. Although some fluorescence-based automated inspection instrumentation has been developed for food products, there remains a need for devices that can assist on-site inspectors performing visual sanitation inspection of the surfaces of food processing/handling equipment. This paper reports the development of an inexpensive handheld imaging device designed to visualize fluorescence emissions and intended to help detect the presence of fecal contaminants, organic residues, and bacterial biofilms at multispectral fluorescence emission bands. The device consists of a miniature camera, multispectral (interference) filters, and high power LED illumination. With WiFi communication, live inspection images from the device can be displayed on smartphone or tablet devices. This imaging device could be a useful tool for assessing the effectiveness of sanitation procedures and for helping processors to minimize food safety risks or determine potential problem areas. This paper presents the design and development including evaluation and optimization of the hardware components of the imaging devices.

  7. Development of head docking device for linac-based radiosurgery with a Neptun 10 PC linac.

    Science.gov (United States)

    Khoshbin Khoshnazar, Alireza; Bahreyni Toossi, Mohammad Taghi; Hashemian, Abdolreza; Salek, Roham

    Stereotactic radiosurgery is a method for focused irradiation of intracranial lesions. Linac-based radiosurgery is currently performed by two techniques: couch mounted and pedestal mounted. In the first technique a device is required to affix the patient's head to the couch and neoreover to translate it accurately. Structure of such a device constructed by the authors plus acceptance test performed for evaluation is described in the article. A head docking device has been designed and constructed according to geometry of linac's couch and also desired functions. The device is cornpletely made from aluminum and consists of four major components: attachment bar, lower structure with four moveing accuracy mechanical stability and isocentric accuracy were assessed in the frame of acceptance test. Translating accuracy, mechanical stability and isocentric accuracy were found to be respectively: 1 mm, 1.64 mm and 3.2 mm with accuracy of 95%. According to AAPM report no. 54, a head docking device should translate head with an accuracy of 1 mm; this recommendation has been met. Moreover, we have demonstrated that the isocentric accuracy and mechanical stability of the device are sufficient that the device on confidently be used in stereotactic treatment. PMID:17664152

  8. ALL-CERAMIC APPLIANCES FOR PROSTHETIC REHABILITATION IN YOUNG PATIENTS

    Directory of Open Access Journals (Sweden)

    Alexandru BASNO

    2016-03-01

    Full Text Available The aim of the present study was to assess a possible fixed rehabilitation in young patients, by means of CAD-CAM techniques. Materials and method. The CERCON substractive technique with zirconium oxide blanks was applied. Discussion. The obtained prosthetic structures are characterized by a better aesthetic integration, optimum marginal adaptation and suitable clinical longevity. Conclusions. All-ceramic prostheses appear as a biological solution in the prosthetic rehabilitation of young patients, as they require reduced removal of both enamel and dentin, while obeying the biological conservative principle of treatment.

  9. Diagnostic flowcharts in osteomyelitis, spondylodiscitis and prosthetic joint infection

    International Nuclear Information System (INIS)

    Infections of the bone, spine and prosthetic joints are serious and complex conditions to diagnose and to treat. Structured diagnostic workup may very well improve the accuracy and speed of diagnosis, thereby improving the outcome since treatment may very well be more successful and less harmful if timely management is started. Literature shows no uniform advise on diagnosis. The EANM organized a consensus meeting with representatives from the involved disciplines in order to develop common flowcharts for the diagnosis of osteomyelitis, spondylodiscitis and prosthetic joint infections. In this report the proceedings of this consensus meeting, including the proposed flowcharts for diagnosis, are published.

  10. Real-Time Occupant Based Plug-in Device Control Using ICT in Office Buildings

    Directory of Open Access Journals (Sweden)

    Woo-Bin Bae

    2016-03-01

    Full Text Available The purpose of this study is to reduce the unnecessary plug loads used by computers, monitors, and computer peripheral devices, all of which account for more than 95% of the entire plug loads of an office building. To this end, an occupant-based plug-in device control (OBC-P software was developed. The OBC-P software collects real-time information about the presence or absence of occupants who are connected to the access point through the Wifi and controls the power of monitors or computers, while a standby power off device controls computer peripheral devices. To measure the plug load saving of the occupant-based plug-in device control, an experiment was conducted, targeting 10 occupants of three research labs of the graduate school, for two weeks. The experiment results showed that it could save the plug loads of monitors and computer peripheral devices by 15% in the Awake mode, and by 26% in the Sleep mode.

  11. The PMIPv6-Based Group Binding Update for IoT Devices

    Directory of Open Access Journals (Sweden)

    Jianfeng Guan

    2016-01-01

    Full Text Available Internet of Things (IoT has been booming with rapid increase of the various wearable devices, vehicle embedded devices, and so on, and providing the effective mobility management for these IoT devices becomes a challenge due to the different application scenarios as well as the limited energy and bandwidth. Recently, lots of researchers have focused on this topic and proposed several solutions based on the combination of IoT features and traditional mobility management protocols, in which most of these schemes take the IoT devices as mobile networks and adopt the NEtwork MObility (NEMO and its variants to provide the mobility support. However, these solutions are in face of the heavy signaling cost problem. Since IoT devices are generally combined to realize the complex functions, these devices may have similar movement behaviors. Clearly analyzing these characters and using them in the mobility management will reduce the signaling cost and improve the scalability. Motivated by this, we propose a PMIPv6-based group binding update method. In particular, we describe its group creation procedure, analyze its impact on the mobility management, and derive its reduction ratio in terms of signaling cost. The final results show that the introduction of group binding update can remarkably reduce the signaling cost.

  12. Web Services Based Learning Objects Generator for Device-Independent M-Learning

    Directory of Open Access Journals (Sweden)

    Akram Moh. Alkouz

    2006-06-01

    Full Text Available Learning objects, which are the base component of m-learning system, are usually target to modifications in contexts and formats. The device- dependent applications of hand-held devices have proven to be ineffective for creating m-learning courseware. Learning Objects Metadata (LOM is the most popular standard specification for learning objects but lacks the ability to facilitate platforms descriptions. This paper outlines various aspects of design and implementation of Web Services Oriented Rendering Architecture (WSORA which combines LOM Editor with any available published web services. This arrangement is devised in order to make a device-independent m-learning gateway between different mobile devices, such as cell phones, PDA’s, palmtops, and laptops and the vast learning objects available on the World Wide Web. The key technologies behind WSORA are extending the IEEE LOM base scheme structure, LOM Editor, device-independent LO generator, and web services. The major advantage of WSORA is thus achieved to give mobile devices of different types clean and quick access to learning objects customarily designed for desktop browsers.

  13. Lamination-based rapid prototyping of microfluidic devices using flexible thermoplastic substrates.

    Science.gov (United States)

    Paul, Debjani; Pallandre, Antoine; Miserere, Sandrine; Weber, Jérémie; Viovy, Jean-Louis

    2007-04-01

    Transposing highly sensitive DNA separation methods (such as DNA sequencing with high read length or the detection of point mutations) to microchip format without loss of resolution requires fabrication of relatively long (approx. 10 cm) microchannels along with sharp injection bands. Conventional soft lithography methods, such as mold casting or hot-embossing in a press, are not convenient for fabricating long channels. We have developed a lamination-based replication technique for rapid fabrication of sealed microfluidic devices with a 10 cm long, linear separation channel. These devices are fabricated in thin cyclo-olefin copolymer (COC) plastic substrates, thus making the device flexible and capable of assuming a range of 3-D configurations. Due to the good optical properties of COC, this new family of devices combines multiple advantages of planar microfluidics and fused-silica capillaries. PMID:17330225

  14. An Industrial Radipgraphy Exposure Device Based on Measurement of Transmitted Gamma-Ray Intensity

    International Nuclear Information System (INIS)

    In film radiography, underexposure and overexposure may happen particularly when lacking knowledge of specimen material and hollowness. This paper describes a method and a device for determining exposure in industrial gamma-ray radiography based on quick measurement of transmitted gamma-ray intensity with a D3372 Hamamatsu small GM tube. Application software is developed for Android mobile phone to remotely control the device and to display the counting data via Bluetooth. Prior to placing film, the device is placed behind the specimen to be radiographed to determine the exposure time from the transmitted intensity which is independent on source activity, source-to-film distance, specimen thickness and kind of material. The developed technique and device make radiographic process economic, convenient and more reliable.

  15. Flexible ferroelectric polymer devices based on inkjet-printed electrodes from nanosilver ink

    International Nuclear Information System (INIS)

    High-quality silver (Ag) patterns were inkjet-printed with nanosilver ink on a flexible polyethylene terephthalate (PET) substrate. All-solution-processed flexible ferroelectric polymer devices that use inkjet-printed Ag to create their bottom and top electrodes were demonstrated. The active layer, a poly (vinylidene fluoride–trifluoroethylene) (PVDF–TrFE) thin film, was spin-coated from solution. The devices have a remanent polarization of 8.03 μC cm−2 and a coercive field of 68.5 MV m−1, which is comparable to the device with evaporated-Ti electrodes on a silicon substrate. Based on the results presented in this paper, mass production of flexible ferroelectric devices is predictable. (paper)

  16. An industrial radiography exposure device based on measurement of transmitted gamma-ray intensity

    Science.gov (United States)

    Polee, C.; Chankow, N.; Srisatit, S.; Thong-Aram, D.

    2015-05-01

    In film radiography, underexposure and overexposure may happen particularly when lacking information of specimen material and hollowness. This paper describes a method and a device for determining exposure in industrial gamma-ray radiography based on quick measurement of transmitted gamma-ray intensity with a small detector. Application software was developed for Android mobile phone to remotely control the device and to display counting data via Bluetooth communication. Prior to film exposure, the device is placed behind a specimen to measure transmitted intensity which is inversely proportional to the exposure. Unlike in using the conventional exposure curve, correction factors for source decay, source-to- film distance, specimen thickness and kind of material are not needed. The developed technique and device make radiographic process economic, convenient and more reliable.

  17. Design of embedded I/O module based on DeviceNet%基于DeviceNet的嵌入式I/O模块设计

    Institute of Scientific and Technical Information of China (English)

    李月恒; 王美玲; 刘全东

    2013-01-01

      DeviceNet与ModBus协议转换系统由DeviceNet主站,嵌入式I/O模块,ModBus从站三部分组成,实现DeviceNet与ModBus之间的数据交互。嵌入式I/O模块采用ARM7控制器LPC2129实现DeviceNet与ModBus之间的通信,同时以软件的形式实现了一个仅限组2的DeviceNet从站和一个ModBus主站。DeviceNet从站用来解码从DeviceNet主站端接收到的数据,解码后的数据由MCU通过另一个UART接口发送给ModBus从站。UART接口旨在向ModBus从站发送读/写指令。结果表明,基于DeviceNet总线的嵌入式I/O模块可以很好地与基于ModBus总线的设备进行通信。%  DeviceNet and ModBus protocols′ conversion system is composed of DeviceNet master station,embedded I/O module and ModBus slave station to realize the data exchange between DeviceNet and ModBus protocols. In this paper,ARM7 controller LPC2129 is adopted in the embedded I/O module to implement the communication between ModBus and DeviceNet. The DeviceNet slave and a CAN master stations which limit Group 2 only are realized in the form of software. DeviceNet slave station is designed to decode the data received from the DeviceNet master station. After that,the decoded data from MCU through another UART interface is sent to the ModBus slave station. UART interface send data to ModBus. The results show that the embedded I/O module based on the DeviceNet bus can communicated with the equipment based on ModBus bus well.

  18. Viseu Mobile: A location based Augmented Reality tour guide for mobile devices

    Directory of Open Access Journals (Sweden)

    M.L. Martins

    2015-11-01

    Full Text Available This article reports on the project "Viseu na Palma da Mão", which is based on a Augmented Reality app for mobile devices, whose main purpose is to maximise the tourists’ experience when visiting the town of Viseu. The paper starts by presenting a reflection on Augmented Reality and its potential and applications, with a special emphasis on the tourism industry. The increasing possibility to access the Internet anytime, anywhere, together with the unprecedented growth of mobile device penetration has boosted the development of specific applications that seek to respond to the increasing demands of tourists. It is on this premise that the app Viseu Mobile emerges, seeking to enhance the constant use of mobile devices, and making them act as a personal tour guide, based on location based information. The different stages of development and different features of the application are also explained

  19. The effect of wireless LAN-based PACS device for portable imaging modalities.

    Science.gov (United States)

    Lee, Hak Jong; Lee, Kyoung Ho; Hwang, Sung Il; Kim, Hyun-Chul; Seo, Eun Hee; Kim, Tae Gee; Ha, Kyoo-Seob

    2010-04-01

    The aim of this study was to develop wireless Picture Archiving and Communication System (PACS) device and to analyze its effect on image transfer from portable imaging modalities to the main PACS server. Using a laptop computer equipped with wireless local area network (LAN), the authors developed a wireless PACS device with DICOM modality worklist and DICOM storage server modules. This laptop computer could be easily fixed to portable imaging modalities such as ultrasound machines. From May to August 2007, 112 portable examinations were evaluated. Of these, 62 were done with wireless LAN-based PACS device, and 50 were done without wireless PACS device. To evaluate the impact of the wireless LAN-based PACS device on productivity and workflow, we analyzed the mean time delay and standard deviations (SD) both in cases where wireless LAN-based PACS device was used and in cases where it was not used. Statistical analysis was performed using a t test. The mean time interval from image acquisition to storage in the main PACS when the wireless LAN-based PACS device was used was 342.4 s (5 min and 42.4 s, SD = 509.2 s). When the wireless PACS was not used, the mean time interval was 2,305.5 s (38 min and 25.5 s, SD = 1,371.8 s). The mean time interval was statistically different between the two groups (t test, p portable machines and in promoting effective and rapid treatment of patients who have undergone portable imaging examinations. PMID:19137373

  20. PANATIKI: A Network Access Control Implementation Based on PANA for IoT Devices

    Directory of Open Access Journals (Sweden)

    Antonio F. Gomez Skarmeta

    2013-11-01

    Full Text Available Internet of Things (IoT networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data or access network services. However, only authenticated and authorized devices can, in general, establish this connection. The so-called authentication, authorization and accounting (AAA services are in charge of performing these tasks on the Internet. Thus, it is necessary to deploy protocols that allow constrained devices to verify their credentials against AAA infrastructures. The Protocol for Carrying Authentication for Network Access (PANA has been standardized by the Internet engineering task force (IETF to carry the Extensible Authentication Protocol (EAP, which provides flexible authentication upon the presence of AAA. To the best of our knowledge, this paper is the first deep study of the feasibility of EAP/PANA for network access control in constrained devices. We provide light-weight versions and implementations of these protocols to fit them into constrained devices. These versions have been designed to reduce the impact in standard specifications. The goal of this work is two-fold: (1 to demonstrate the feasibility of EAP/PANA in IoT devices; (2 to provide the scientific community with the first light-weight interoperable implementation of EAP/PANA for constrained devices in the Contiki operating system (Contiki OS, called PANATIKI. The paper also shows a testbed, simulations and experimental results obtained from real and simulated constrained devices.

  1. PANATIKI: a network access control implementation based on PANA for IoT devices.

    Science.gov (United States)

    Moreno Sanchez, Pedro; Marin Lopez, Rafa; Gomez Skarmeta, Antonio F

    2013-01-01

    Internet of Things (IoT) networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP)-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data) or access network services. However, only authenticated and authorized devices can, in general, establish this connection. The so-called authentication, authorization and accounting (AAA) services are in charge of performing these tasks on the Internet. Thus, it is necessary to deploy protocols that allow constrained devices to verify their credentials against AAA infrastructures. The Protocol for Carrying Authentication for Network Access (PANA) has been standardized by the Internet engineering task force (IETF) to carry the Extensible Authentication Protocol (EAP), which provides flexible authentication upon the presence of AAA. To the best of our knowledge, this paper is the first deep study of the feasibility of EAP/PANA for network access control in constrained devices. We provide light-weight versions and implementations of these protocols to fit them into constrained devices. These versions have been designed to reduce the impact in standard specifications. The goal of this work is two-fold: (1) to demonstrate the feasibility of EAP/PANA in IoT devices; (2) to provide the scientific community with the first light-weight interoperable implementation of EAP/PANA for constrained devices in the Contiki operating system (Contiki OS), called PANATIKI. The paper also shows a testbed, simulations and experimental results obtained from real and simulated constrained devices. PMID:24189332

  2. Conductivity based on selective etch for GaN devices and applications thereof

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu; Sun, Qian; Han, Jung

    2015-12-08

    This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm.sup.2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

  3. Investigation of the synaptic device based on the resistive switching behavior in hafnium oxide

    Directory of Open Access Journals (Sweden)

    Bin Gao

    2015-02-01

    Full Text Available Metal-oxide based electronics synapse is promising for future neuromorphic computation application due to its simple structure and fab-friendly materials. HfOx resistive switching memory has been demonstrated superior performance such as high speed, low voltage, robust reliability, excellent repeatability, and so on. In this work, the HfOx synaptic device was investigated based on its resistive switching phenomenon. HfOx resistive switching device with different electrodes and dopants were fabricated. TiN/Gd:HfOx/Pt stack exhibited the best synaptic performance, including controllable multilevel ability and low training energy consumption. The training schemes for memory and forgetting were developed.

  4. Semiconductor device-based sensors for gas, chemical, and biomedical applications

    CERN Document Server

    Ren, Fan

    2011-01-01

    Sales of U.S. chemical sensors represent the largest segment of the multi-billion-dollar global sensor market, which includes instruments for chemical detection in gases and liquids, biosensors, and medical sensors. Although silicon-based devices have dominated the field, they are limited by their general inability to operate in harsh environments faced with factors such as high temperature and pressure. Exploring how and why these instruments have become a major player, Semiconductor Device-Based Sensors for Gas, Chemical, and Biomedical Applications presents the latest research, including or

  5. DroidGuardian : an application firewall for android OS-based devices

    OpenAIRE

    Gonçalo, Rui Miguel de Carvalho Videira

    2014-01-01

    Dissertação de Mestrado em Informática Mobile devices running Android operating system are increasingly used to surf the web, and, generally speaking, to access a broad spectrum of network-based services. Its successful deployment as a mobile platform, however, also means it is an increasingly relevant target of malicious efforts that try to identify and exploit its vulnerabilities, and to gain access to valuable personal and organizational data. On the other hand, Android OS-based devices...

  6. Dental prosthetic status and prosthetic needs of institutionalised elderly population in oldage homes of jabalpur city, madhya pradesh, India.

    Science.gov (United States)

    Deogade, Suryakant C; Vinay, S; Naidu, Sonal

    2013-12-01

    Oral disorders are cumulative throughout life and hence unfavourable outcomes are likely to be greatest among the elderly. A descriptive cross-sectional study was conducted among institutionalized geriatric population in old-age homes of Jabalpur city, Madhya Pradesh, to assess their prosthetic status and prosthetic needs. A cross-sectional survey was conducted in all the four old-age homes of Jabalpur city, Madhya Pradesh state, India. All residents aged 60 years and above formed the study population. The recording of prosthetic status and prosthetic needs was carried out according to the World Health Organisation (WHO) Oral Health Assessment Form (1997). A total of 224 individuals were included in the study of which 123 were females and 101 were males. Seventy five percent of the females and 55 % of the males had no prostheses in their upper arch and 61 % of the females and 76 % of the males had no prostheses in their lower arch. More number of males presented with 'Bridges' in their upper arch when compared to females (P value = 0.006). Highest prosthetic need in males was multi-unit prosthesis (42 % in upper arch and 41 % in lower arch) whereas, females' required full prosthesis (39 % in both the upper arch and lower arches). Ageing presents some formidable challenges, particularly with the institutionalised. This study clearly demonstrates a high insufficiency of prosthetic care among the institutionalized elderly population. Any preparation towards the provision of oral health care should not be limited to treatment alone but, more importantly focus on empowering this elderly community with information and education programmes. PMID:24431796

  7. Real-time prediction learning for the simultaneous actuation of multiple prosthetic joints.

    Science.gov (United States)

    Pilarski, Patrick M; Dick, Travis B; Sutton, Richard S

    2013-06-01

    Integrating learned predictions into a prosthetic control system promises to enhance multi-joint prosthesis use by amputees. In this article, we present a preliminary study of different cases where it may be beneficial to use a set of temporally extended predictions--learned and maintained in real time--within an engineered or learned prosthesis controller. Our study demonstrates the first successful combination of actor-critic reinforcement learning with real-time prediction learning. We evaluate this new approach to control learning during the myoelectric operation of a robot limb. Our results suggest that the integration of real-time prediction and control learning may speed control policy acquisition, allow unsupervised adaptation in myoelectric controllers, and facilitate synergies in highly actuated limbs. These experiments also show that temporally extended prediction learning enables anticipatory actuation, opening the way for coordinated motion in assistive robotic devices. Our work therefore provides initial evidence that realtime prediction learning is a practical way to support intuitive joint control in increasingly complex prosthetic systems. PMID:24187253

  8. Prosthetic EMG control enhancement through the application of man-machine principles

    Science.gov (United States)

    Simcox, W. A.

    1977-01-01

    An area in medicine that appears suitable to man-machine principles is rehabilitation research, particularly when the motor aspects of the body are involved. If one considers the limb, whether functional or not, as the machine, the brain as the controller and the neuromuscular system as the man-machine interface, the human body is reduced to a man-machine system that can benefit from the principles behind such systems. The area of rehabilitation that this paper deals with is that of an arm amputee and his prosthetic device. Reducing this area to its man-machine basics, the problem becomes one of attaining natural multiaxis prosthetic control using Electromyographic activity (EMG) as the means of communication between man and prothesis. In order to use EMG as the communication channel it must be amplified and processed to yield a high information signal suitable for control. The most common processing scheme employed is termed Mean Value Processing. This technique for extracting the useful EMG signal consists of a differential to single ended conversion to the surface activity followed by a rectification and smoothing.

  9. Anomalous Threshold Voltage Variability of Nitride Based Charge Storage Nonvolatile Memory Devices

    Directory of Open Access Journals (Sweden)

    Meng Chuan Lee

    2013-01-01

    Full Text Available Conventional technology scaling is implemented to meet the insatiable demand of high memory density and low cost per bit of charge storage nonvolatile memory (NVM devices. In this study, effect of technology scaling to anomalous threshold voltage ( variability is investigated thoroughly on postcycled and baked nitride based charge storage NVM devices. After long annealing bake of high temperature, cell’s variability of each subsequent bake increases within stable distribution and found exacerbate by technology scaling. Apparent activation energy of this anomalous variability was derived through Arrhenius plots. Apparent activation energy (Eaa of this anomalous variability is 0.67 eV at sub-40 nm devices which is a reduction of approximately 2 times from 110 nm devices. Technology scaling clearly aggravates this anomalous variability, and this poses reliability challenges to applications that demand strict control, for example, reference cells that govern fundamental program, erase, and verify operations of NVM devices. Based on critical evidence, this anomalous variability is attributed to lateral displacement of trapped charges in nitride storage layer. Reliability implications of this study are elucidated. Moreover, potential mitigation methods are proposed to complement technology scaling to prolong the front-runner role of nitride based charge storage NVM in semiconductor flash memory market.

  10. Cloud Based Application Development for Accessing Restaurant Information on Mobile Device using LBS

    Directory of Open Access Journals (Sweden)

    Keerthi S. Shetty

    2011-11-01

    Full Text Available Over the past couple of years, the extent of the services provided on the mobile devices has increasedrapidly. A special class of service among them is the Location Based Service(LBS which depends on thegeographical position of the user to provide services to the end users. However, a mobile device is still resource constrained, and some applications usually demand more resources than a mobile device can a ord. To alleviate this, a mobile device should get resources from an external source. One of such sources is cloud computing platforms. We can predict that the mobile area will take on a boom with the advent of this new concept. The aim of this paper is to exchange messages between user and location service provider in mobile device accessing the cloud by minimizing cost, data storage and processing power. Our main goalis to provide dynamic location-based service and increase the information retrieve accuracy especially on the limited mobile screen by accessing cloud application. In this paper we present location based restaurant information retrieval system and we have developed our application in Android.

  11. Fast, Compact, and High Quality LSTM-RNN Based Statistical Parametric Speech Synthesizers for Mobile Devices

    OpenAIRE

    Zen, Heiga; Agiomyrgiannakis, Yannis; Egberts, Niels; Henderson, Fergus; Szczepaniak, Przemysław

    2016-01-01

    Acoustic models based on long short-term memory recurrent neural networks (LSTM-RNNs) were applied to statistical parametric speech synthesis (SPSS) and showed significant improvements in naturalness and latency over those based on hidden Markov models (HMMs). This paper describes further optimizations of LSTM-RNN-based SPSS for deployment on mobile devices; weight quantization, multi-frame inference, and robust inference using an {\\epsilon}-contaminated Gaussian loss function. Experimental r...

  12. UPPER LIMB PROSTHETIC FOR STROKE AFFECTED PATIENTS

    Directory of Open Access Journals (Sweden)

    DEBIKA KHANRA,

    2011-04-01

    Full Text Available Paralysis causes loss of muscle function and loss of feeling in the affected area. The main problem faced by the patients after paralysis is muscle atrophy caused due to non-functionality of the stump. Orthotics is an orthopedic device which supports the function of the arm, leg or torso. This paper deals with the design of an upper limb orthotic device which has a hollow shell/ braces structure and can be used by paralyzed patients to bring about simple hand movements independently by the patient.

  13. A novel vacuum assisted closure therapy model for use with percutaneous devices

    OpenAIRE

    Cook, Saranne J.; Nichols, Francesca R.; Brunker, Lucille B.; Bachus, Kent N.

    2014-01-01

    Long-term maintenance of a dermal barrier around a percutaneous prosthetic device remains a common clinical problem. A technique known as Negative Pressure Wound Therapy (NPWT) uses negative pressure to facilitate healing of impaired and complex soft tissue wounds. However, the combination of using negative pressure with percutaneous prosthetic devices has not been investigated. The goal of this study was to develop a methodology to apply negative pressure to the tissues surrounding a percuta...

  14. A 3D Hand-drawn Gesture Input Device Using Fuzzy ARTMAP-based Recognizer

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2006-06-01

    Full Text Available In this paper, a novel input device based on 3D dynamic hand-drawn gestures is presented. It makes use of inertial sensor and pattern recognition technique. Fuzzy ARTMAP based recognizer is adopted to realize gesture recognition by using 3-axis acceleration signals directly instead of reproduced trajectories of gestures. The proposed method may relax motion constraints during inputting a gesture, which is more convenient for user. This prototype of input device has been implemented on a remote controller to manipulate TVs. The recognition rate of 20 gestures is higher than 97%. It clearly shows the effectiveness and feasibility of the proposed input device. As a result, it is a powerful, flexible interface for modern electronic products.

  15. Simultaneous recording of rat auditory cortex and thalamus via a titanium-based, microfabricated, microelectrode device

    Science.gov (United States)

    McCarthy, P. T.; Rao, M. P.; Otto, K. J.

    2011-08-01

    Direct recording from sequential processing stations within the brain has provided opportunity for enhancing understanding of important neural circuits, such as the corticothalamic loops underlying auditory, visual, and somatosensory processing. However, the common reliance upon microwire-based electrodes to perform such recordings often necessitates complex surgeries and increases trauma to neural tissues. This paper reports the development of titanium-based, microfabricated, microelectrode devices designed to address these limitations by allowing acute recording from the thalamic nuclei and associated cortical sites simultaneously in a minimally invasive manner. In particular, devices were designed to simultaneously probe rat auditory cortex and auditory thalamus, with the intent of recording auditory response latencies and isolated action potentials within the separate anatomical sites. Details regarding the design, fabrication, and characterization of these devices are presented, as are preliminary results from acute in vivo recording.

  16. Control Structures for VSC-based FACTS Devices under Normal and Faulted AC-systems

    Science.gov (United States)

    Babaei, Saman

    This thesis is concerned with improving the Flexible AC Transmission Systems (FACTS) devices performance under the normal and fault AC-system conditions by proposing new control structures and also converter topologies. The combination of the increasing electricity demand and restrictions in expanding the power system infrastructures has urged the utility owners to deploy the utility-scaled power electronics in the power system. Basically, FACTS is referred to the application of the power electronics in the power systems. Voltage Source Converter (VSC) is the preferred building block of the FACTS devices and many other utility-scale power electronics applications. Despite of advances in the semiconductor technology and ultra-fast microprocessor based controllers, there are still many issues to address and room to improve[25]. An attempt is made in this thesis to address these important issues of the VSC-based FACTS devices and provide solutions to improve them.

  17. Liquid Crystal-Based Beam Steering Device Development for NASA Applications

    Science.gov (United States)

    Pouch, John; Nguyen, Hung; Miranda, Felix; Bos, Philip; Lavrentovich, Oleg; Wang, Xinghua

    2004-01-01

    The NASA Computing, Information and Communications Technology (CICT) Program is supporting the development of liquid crystal-based beam steering devices. The device would use inexpensive, light-weight, optical components, and it would have the following capabilities: electronic beam scanning to angles above 1 milliradian, and submicroradian beam pointing accuracy. In order to correct for the imperfections resulting from the space-deployable optics, the technique of wave-front correction would be implemented. Hence, the output beam quality would be maintained. The potential applications could include satellite tracking, near-Earth inter-satellite communications, deep-space communications, and optical phased array systems. The status of the beam steering device development based on the liquid crystal technology and its relationship to prospective NASA mission scenarios will be described.

  18. A field-emission based vacuum device for the generation of THz waves

    Science.gov (United States)

    Lin, Ming-Chieh

    2005-03-01

    Terahertz waves have been used to characterize the electronic, vibrational and compositional properties of solid, liquid and gas phase materials during the past decade. More and more applications in imaging science and technology call for the well development of THz wave sources. Amplification and generation of a high frequency electromagnetic wave are a common interest of field emission based devices. In the present work, we propose a vacuum electronic device based on field emission mechanism for the generation of THz waves. To verify our thinking and designs, the cold tests and the hot tests have been studied via the simulation tools, SUPERFISH and MAGIC. In the hot tests, two types of electron emission mechanisms are considered. One is the field emission and the other is the explosive emission. The preliminary design of the device is carried out and tested by the numerical simulations. The simulation results show that an electronic efficiency up to 4% can be achieved without employing any magnetic circuits.

  19. Realization of Minimum and Maximum Gate Function in Ta2O5-based Memristive Devices

    Science.gov (United States)

    Breuer, Thomas; Nielen, Lutz; Roesgen, Bernd; Waser, Rainer; Rana, Vikas; Linn, Eike

    2016-04-01

    Redox-based resistive switching devices (ReRAM) are considered key enablers for future non-volatile memory and logic applications. Functionally enhanced ReRAM devices could enable new hardware concepts, e.g. logic-in-memory or neuromorphic applications. In this work, we demonstrate the implementation of ReRAM-based fuzzy logic gates using Ta2O5 devices to enable analogous Minimum and Maximum operations. The realized gates consist of two anti-serially connected ReRAM cells offering two inputs and one output. The cells offer an endurance up to 106 cycles. By means of exemplary input signals, each gate functionality is verified and signal constraints are highlighted. This realization could improve the efficiency of analogous processing tasks such as sorting networks in the future.

  20. 77 FR 16126 - Microbiology Devices; Reclassification of Nucleic Acid-Based Systems for Mycobacterium tuberculosis

    Science.gov (United States)

    2012-03-19

    ... Food and Drug Administration 21 CFR Part 866 Microbiology Devices; Reclassification of Nucleic Acid... the Microbiology Devices Panel of the Medical Devices Advisory Committee (Microbiology Devices Panel.... VI. Risks to Health After considering the information discussed by the Microbiology Devices...

  1. Skin-inspired electronic devices

    Directory of Open Access Journals (Sweden)

    Alex Chortos

    2014-09-01

    Full Text Available Electronic devices that mimic the properties of skin have potential important applications in advanced robotics, prosthetics, and health monitoring technologies. Methods for measuring tactile and temperature signals have progressed rapidly due to innovations in materials and processing methods. Imparting skin-like stretchability to electronic devices can be accomplished by patterning traditional electronic materials or developing new materials that are intrinsically stretchable. The incorporation of sensing methods with transistors facilitates large-area sensor arrays. While sensor arrays have surpassed the properties of human skin in terms of sensitivity, time response, and device density, many opportunities remain for future development.

  2. The fabrication of polyfluorene and polycarbazole-based photovoltaic devices using an air-stable process route

    Energy Technology Data Exchange (ETDEWEB)

    Bovill, E.; Lidzey, D. G., E-mail: d.g.lidzey@sheffield.ac.uk [Department of Physics and Astronomy, The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Yi, H.; Iraqi, A. [Department of Chemistry, The University of Sheffield, The Dainton Building, Sheffield S3 7HF (United Kingdom)

    2014-12-01

    We report a comparative study based on the fabrication of polymer:fullerene photovoltaic (PV) devices incorporating carbazole, fluorene, and a PTB based co-polymer. We have explored the efficiency and performance of such devices when the active polymer:fullerene layer is deposited by spin-casting either under nitrogen or ambient conditions. We show that PV devices based on carbazole and fluorene based materials have very similar power conversion efficiencies when processed under both air and nitrogen, with other photobleaching measurements suggesting that such materials have comparatively enhanced photostability. Devices based on the PTB co-polymer, however, have reduced efficiency when processed in air.

  3. Assessment of preload in carbon coated prosthetic screws

    Directory of Open Access Journals (Sweden)

    Dilcele Silva Moreira Dziedzic

    2012-06-01

    Full Text Available Introduction: The mechanical aspects of tightening screws over implants are important to ensure a successful prosthetic rehabilitation. Screw loosening is a common problem that can be avoided with passive adaptation of the components and an increased tensile force developed in the screw, a preload. Objective: This in vitro study evaluated the effect on preload of a carbon lubricant deposited on the surface of titanium alloy prosthetic screws: conventional Ti6Al4V and surface enhanced. Material and methods: Conventional titanium alloy prosthetic (n = 7 and carbon coating surface enhanced screws(n = 7 were compared. Each prosthetic screw supporting a metallic UCLA over an implant was tightened with the manufacturer’s recommended torque of 32 N.cm. The removal torque values, recorded for ten consecutive cycles of tightening and removal, were used to estimate the preload. Implant blocks were then sectioned and the interfaces were observed by light microscopy. Results: The lowest removal torque, and consequently the highest preload values, was achieved for the lubricated group in most cycles. The contacts between threads were located at the coronal aspect of all observed screw mating threads. Conclusion: Data indicate that the lower coefficient of friction of a carbon lubricant can generate higher preload. The machining precision observed produced the adaptation and regular contact interfaces.

  4. Laser photonics application in prosthetic dentistry for denture design optimization

    Science.gov (United States)

    Grosmann, M. H.; Kiryushin, M. A.; Larkin, A. I.; Lebedenko, A. I.; Lebedenko, I. Yu.; Lopatina, N. A.; Osincev, A. V.; Shchepinov, V. P.; Shchepinova, I. V.

    2010-06-01

    The aim of this work is to demonstrate that holographic and speckle interferometry—laser photonics methods are compatible and useful for prosthetic stomatology. These methods allow to study the deformation of the mandible after insertion of mini-implants of various forms, and to give the practical medical recommendations.

  5. Case report of Streptomyces endocarditis of a prosthetic aortic valve.

    Science.gov (United States)

    Mossad, S B; Tomford, J W; Stewart, R; Ratliff, N B; Hall, G S

    1995-01-01

    We describe the first case of prosthetic valve endocarditis due to a Streptomyces sp. The patient presented with fever, cutaneous embolic lesions, and bacteremia 3 months after aortic valve replacement. Treatment required valve replacement and a long course of parenteral imipenem. PMID:8586732

  6. Case report of Streptomyces endocarditis of a prosthetic aortic valve.

    OpenAIRE

    Mossad, S B; Tomford, J W; Stewart, R; Ratliff, N B; Hall, G. S.

    1995-01-01

    We describe the first case of prosthetic valve endocarditis due to a Streptomyces sp. The patient presented with fever, cutaneous embolic lesions, and bacteremia 3 months after aortic valve replacement. Treatment required valve replacement and a long course of parenteral imipenem.

  7. An unusual cause of prosthetic joint infection: Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Bilgül Mete

    2012-06-01

    Full Text Available Mycobacterium tuberculosis is a rare cause of prosthetic joint infection. Early diagnosis is critical for a good treatment response.Here, we report a case of prosthetic joint infection due to M.tuberculosis. A32-year old woman was admitted toour clinic for fever and drainage of right hip with prosthesis. After several interventions, she was diagnosed as prostheticinfection due to M.tuberculosis. Although the diagnosis was delayed because of the difficulties to yield M.tuberculosis,the outcome was good with medical therapy for 12-month and staged exchange of prosthesis.Approach to diagnosis must involve the histopathological examination of the tissue, mycobacterial cultures and acidfaststaining and when repeated cultures and examination of histological samples from infected joints are negative,tuberculosis should be kept in mind in the differential diagnosis of prosthetic joint infection. While the treatment modalitiesvary in English literature, it is clear that treatment must involve both medical and surgical approaches. J MicrobiolInfect Dis 2012; 2(2: 72-75Key words: Prosthetic joint, infection, tuberculosis

  8. Device and packaging considerations for MMIC-based millimeter-wave quasi-optical amplifier arrays

    Science.gov (United States)

    Kolias, Nicholas J.; Kazior, Thomas E.; Chen, Yan; Wright, Warren

    1999-11-01

    Practical implementation of millimeter-wave quasi-optical amplifier arrays will require high device uniformity across the array, efficient coupling to and from each gain device, good device-to-device isolation, and efficient heat removal. This paper presents techniques that address these issues for a 44 GHz MMIC-based design. To improve device uniformity, a double selective gate recess approach is introduced which results in a demonstrated 3 - 5X improvement in uniformity when compared to Raytheon's standard production pHEMT process. For packaging, direct backside interconnect technology (DBIT) is introduced as a bondwire-free scheme for connecting each amplifier to the array. This approach significantly reduces interconnect loss by reducing interconnect inductance. Measured insertion loss at 44 GHz for the DBIt transition is 0.35 dB compared to 2.3 dB for a typical bondwire transition produced on a manufacturing automated bonding machine. By eliminating bondwires which tend to radiate at millimeter wave frequencies, the DBIT approach also significantly improves the device-to-device isolation, thereby improving the array stability. The DBIT approach would not be viable if it could not effectively dissipate heat (a typical 25 watt array generates greater than 100 watts of heat). Finite element thermal analysis results are presented which show that the DBIT approach adds a tolerable 15.5 degree(s)C temperature rise over a standard solder-based MMIC die-attach to a heatsink. Thus, the DBIT approach, along with the double selective gate recess process, provides an attractive, low-loss, bondwire-free approach for producing uniform amplifier arrays.

  9. Metal oxide resistive random access memory based synaptic devices for brain-inspired computing

    Science.gov (United States)

    Gao, Bin; Kang, Jinfeng; Zhou, Zheng; Chen, Zhe; Huang, Peng; Liu, Lifeng; Liu, Xiaoyan

    2016-04-01

    The traditional Boolean computing paradigm based on the von Neumann architecture is facing great challenges for future information technology applications such as big data, the Internet of Things (IoT), and wearable devices, due to the limited processing capability issues such as binary data storage and computing, non-parallel data processing, and the buses requirement between memory units and logic units. The brain-inspired neuromorphic computing paradigm is believed to be one of the promising solutions for realizing more complex functions with a lower cost. To perform such brain-inspired computing with a low cost and low power consumption, novel devices for use as electronic synapses are needed. Metal oxide resistive random access memory (ReRAM) devices have emerged as the leading candidate for electronic synapses. This paper comprehensively addresses the recent work on the design and optimization of metal oxide ReRAM-based synaptic devices. A performance enhancement methodology and optimized operation scheme to achieve analog resistive switching and low-energy training behavior are provided. A three-dimensional vertical synapse network architecture is proposed for high-density integration and low-cost fabrication. The impacts of the ReRAM synaptic device features on the performances of neuromorphic systems are also discussed on the basis of a constructed neuromorphic visual system with a pattern recognition function. Possible solutions to achieve the high recognition accuracy and efficiency of neuromorphic systems are presented.

  10. A review of piezoelectric-based electrical energy harvesting methods and devices for munitions

    Science.gov (United States)

    Rastegar, Jahangir; Pereira, Carlos M.; Feng, Dake

    2016-04-01

    This paper presents a review of piezoelectric based energy harvesting devices and their charge collection and storage electronics for use in very harsh environment of gun-fired munitions. A number of novel classes of such energy-harvesting power sources that have been developed for gun-fired munitions and similar applications, including one with integrated safety and firing setback event detection electronics and logic circuitry. The power sources are designed to harvest energy from firing acceleration and vibratory motions during the flight. As an example, the application of the developed piezoelectric based energy harvesting devices with event detection circuitry to the development of self-powered initiators or switching devices with full no-fire safety circuitry for protection against accidental drops, transportation vibration, and other similar low amplitude accelerations and/or high amplitude but short duration acceleration events is presented. The designs allow the use of a very small piezoelectric elements, thereby making such devices to be highly miniaturized. These devices can be readily hardened to withstand very high G firing setback accelerations in excess of 100,000 G and the harsh firing environments. The design of prototypes and testing in shock loading machines, air guns and actual firing are presented.

  11. CMOS compatible electrode materials selection in oxide-based memory devices

    Science.gov (United States)

    Zhuo, V. Y.-Q.; Li, M.; Guo, Y.; Wang, W.; Yang, Y.; Jiang, Y.; Robertson, J.

    2016-07-01

    Electrode materials selection guidelines for oxide-based memory devices are constructed from the combined knowledge of observed device operation characteristics, ab-initio calculations, and nano-material characterization. It is demonstrated that changing the top electrode material from Ge to Cr to Ta in the Ta2O5-based memory devices resulted in a reduction of the operation voltages and current. Energy Dispersed X-ray (EDX) Spectrometer analysis clearly shows that the different top electrode materials scavenge oxygen ions from the Ta2O5 memory layer at various degrees, leading to different oxygen vacancy concentrations within the Ta2O5, thus the observed trends in the device performance. Replacing the Pt bottom electrode material with CMOS compatible materials (Ru and Ir) further reduces the power consumption and can be attributed to the modification of the Schottky barrier height and oxygen vacancy concentration at the electrode/oxide interface. Both trends in the device performance and EDX results are corroborated by the ab-initio calculations which reveal that the electrode material tunes the oxygen vacancy concentration via the oxygen chemical potential and defect formation energy. This experimental-theoretical approach strongly suggests that the proper selection of CMOS compatible electrode materials will create the critical oxygen vacancy concentration to attain low power memory performance.

  12. A proposed model of the response of the anophthalmic socket to prosthetic eye wear and its application to the management of mucoid discharge.

    Science.gov (United States)

    Pine, Keith R; Sloan, Brian H; Jacobs, Robert J

    2013-08-01

    Mucoid discharge associated with prosthetic eye wear can be a distressing condition that affects the quality of life of people who have lost an eye. Discharge is the second highest concern of experienced prosthetic eye wearers after health of the companion eye and is prevalent in anophthalmic populations. Specific causes of mucoid discharge such as infections and environmental allergens are well understood, but non-specific causes are unknown and an evidence based protocol for managing non-specific discharge is lacking. Current management is based on prosthesis removal and cleaning, and professional re-polishing of the prosthesis. Tear protein deposits accumulate on prosthetic eyes. These deposits mediate the response of the socket to prosthetic eye wear and their influence (good and bad) is determined by differing cleaning regimes and standards of surface finish. This paper proposes a three-phase model that describes the response of the socket to prosthetic eye wear. The phases are: An initial period of wear of a new (or newly-polished) prosthesis when homeostasis is being established (or re-established) within the socket; a second period (equilibrium phase) where beneficial surface deposits have built up on the prosthesis and wear is safe and comfortable, and a third period (breakdown phase) where there is an increasing likelihood of harm from continued wear. The proposed model provides a rationale for a personal cleaning regime to manage non-specific mucoid discharge. Professional care of prosthetic eyes is also important for the management of discharge and evidence for effective surface finishing is reported in this study. Taken together, the proposed regimes for personal and professional care comprise a protocol for managing discharge associated with prosthetic eye wear. The protocol describes prosthetic eye cleaning methods and frequency, and suggests minimum standards for professional polishing. If confirmed, the protocol has the potential to resolve the

  13. Design and Implementation of Prosthetic Arm using Gear Motor Control Technique with Appropriate Testing

    CERN Document Server

    Neogi, Biswarup; Ghosal, Soumya; Das, Achintya; Tibarewala, D N

    2011-01-01

    Any part of the human body replication procedure commences the prosthetic control science. This paper highlights the hardware design technique of a prosthetic arm with implementation of gear motor control aspect. The prosthetic control arm movement has been demonstrated in this paper applying processor programming and with the successful testing of the designed prosthetic model. The architectural design of the prosthetic arm here has been replaced by lighter material instead of heavy metal, as well as the traditional EMG (electro myographic) signal has been replaced by the muscle strain.

  14. Observation of long term potentiation in papain-based memory devices

    KAUST Repository

    Bag, A.

    2014-06-01

    Biological synaptic behavior in terms of long term potentiation has been observed in papain-based (plant protein) memory devices (memristors) for the first time. Improvement in long term potentiation depends on pulse amplitude and width (duration). Continuous/repetitive dc voltage sweep leads to an increase in memristor conductivity leading to a long term memory in the \\'learning\\' processes.

  15. Carbon-Based Materials for Lithium-Ion Batteries, Electrochemical Capacitors, and Their Hybrid Devices.

    Science.gov (United States)

    Yao, Fei; Pham, Duy Tho; Lee, Young Hee

    2015-07-20

    A rapidly developing market for portable electronic devices and hybrid electrical vehicles requires an urgent supply of mature energy-storage systems. As a result, lithium-ion batteries and electrochemical capacitors have lately attracted broad attention. Nevertheless, it is well known that both devices have their own drawbacks. With the fast development of nanoscience and nanotechnology, various structures and materials have been proposed to overcome the deficiencies of both devices to improve their electrochemical performance further. In this Review, electrochemical storage mechanisms based on carbon materials for both lithium-ion batteries and electrochemical capacitors are introduced. Non-faradic processes (electric double-layer capacitance) and faradic reactions (pseudocapacitance and intercalation) are generally explained. Electrochemical performance based on different types of electrolytes is briefly reviewed. Furthermore, impedance behavior based on Nyquist plots is discussed. We demonstrate the influence of cell conductivity, electrode/electrolyte interface, and ion diffusion on impedance performance. We illustrate that relaxation time, which is closely related to ion diffusion, can be extracted from Nyquist plots and compared between lithium-ion batteries and electrochemical capacitors. Finally, recent progress in the design of anodes for lithium-ion batteries, electrochemical capacitors, and their hybrid devices based on carbonaceous materials are reviewed. Challenges and future perspectives are further discussed. PMID:26140707

  16. Ensemble-based multi-objective optimization of on-off control devices under geological uncertainty

    NARCIS (Netherlands)

    Fonseca, R.M.; Leeuwenburgh, O.; Rossa, E.D.; Hof, P.M.J. van den; Jansen, J.D.

    2015-01-01

    We consider robust ensemble-based (EnOpt) multi-objective production optimization of on-off inflow control devices (ICDs) for a sector model inspired on a real-field case. The use of on-off valves as optimization variables leads to a discrete control problem. We propose a re-parameterization of such

  17. An adaptive Hidden Markov Model for activity recognition based on a wearable multi-sensor device

    Science.gov (United States)

    Human activity recognition is important in the study of personal health, wellness and lifestyle. In order to acquire human activity information from the personal space, many wearable multi-sensor devices have been developed. In this paper, a novel technique for automatic activity recognition based o...

  18. Verification of MLC based real-time tumor tracking using an electronic portal imaging device

    OpenAIRE

    Han-Oh, Sarah; Yi, Byong Yong; Lerma, Fritz; Berman, Barry L.; Gui, Minzhi; Yu, Cedric

    2010-01-01

    Purpose: The authors have developed a novel technique using an electronic portal imaging device (EPID) to verify the geometrical accuracy of delivery of dose-rate-regulated tracking (DRRT). This technique, called verification of real-time tracking with EPID (VORTE), can potentially be used for both on-line and off-line quality assurance (QA) of MLC-based dynamic tumor tracking.

  19. MIEC (mixed-ionic-electronic-conduction)-based access devices for non-volatile crossbar memory arrays

    International Nuclear Information System (INIS)

    Several attractive applications call for the organization of memristive devices (or other resistive non-volatile memory (NVM)) into large, densely-packed crossbar arrays. While resistive-NVM devices frequently possess some degree of inherent nonlinearity (typically 3–30× contrast), the operation of large (> 1000×1000 device) arrays at low power tends to require quite large (> 1e7) ON-to-OFF ratios (between the currents passed at high and at low voltages). One path to such large nonlinearities is the inclusion of a distinct access device (AD) together with each of the state-bearing resistive-NVM elements. While such an AD need not store data, its list of requirements is almost as challenging as the specifications demanded of the memory device. Several candidate ADs have been proposed, but obtaining high performance without requiring single-crystal silicon and/or the high processing temperatures of the front-end-of-the-line—which would eliminate any opportunity for 3D stacking—has been difficult. We review our work at IBM Research—Almaden on high-performance ADs based on Cu-containing mixed-ionic-electronic conduction (MIEC) materials [1–7]. These devices require only the low processing temperatures of the back-end-of-the-line, making them highly suitable for implementing multi-layer cross-bar arrays. MIEC-based ADs offer large ON/OFF ratios (>1e7), a significant voltage margin Vm (over which current <10 nA), and ultra-low leakage (< 10 pA), while also offering the high current densities needed for phase-change memory and the fully bipolar operation needed for high-performance RRAM. Scalability to critical lateral dimensions < 30 nm and thicknesses < 15 nm, tight distributions and 100% yield in large (512 kBit) arrays, long-term stability of the ultra-low leakage states, and sub-50 ns turn-ON times have all been demonstrated. Numerical modeling of these MIEC-based ADs shows that their operation depends on Cu+ mediated hole conduction. Circuit simulations

  20. Cobalt-Based Electrolytes for Dye-Sensitized Solar Cells: Recent Advances towards Stable Devices

    Directory of Open Access Journals (Sweden)

    Federico Bella

    2016-05-01

    Full Text Available Redox mediators based on cobalt complexes allowed dye-sensitized solar cells (DSCs to achieve efficiencies exceeding 14%, thus challenging the emerging class of perovskite solar cells. Unfortunately, cobalt-based electrolytes demonstrate much lower long-term stability trends if compared to the traditional iodide/triiodide redox couple. In view of the large-scale commercialization of cobalt-based DSCs, the scientific community has recently proposed various approaches and materials to increase the stability of these devices, which comprise gelling agents, crosslinked polymeric matrices and mixtures of solvents (including water. This review summarizes the most significant advances recently focused towards this direction, also suggesting some intriguing way to fabricate third-generation cobalt-based photoelectrochemical devices stable over time.

  1. Use of high-thermal conductive aluminum nitride based ceramics in vacuum UHF electronic devices

    Directory of Open Access Journals (Sweden)

    Chasnyk V. I.

    2013-06-01

    Full Text Available Analysis of properties and characteristics of the alumina, beryllium oxide and aluminum nitride based ceramic materials used in UHF electronic devices has been made. It was shown that the complex of parameters including structural and functional characteristics of the high-thermal conductive aluminum nitride ceramics prevail over all types of alumina ceramics and is not lower than the same characteristics of the beryllium oxide ceramics especially at the temperatures higher than 450 °C. The examples of the prevailing use of the aluminum nitride ceramics inside vacuum UHF-region devices: TWT’s and klystrons.

  2. GaAs-based Long Wavelength Laser Devices Developed in China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ A research group headed by Prof. Niu Zhichuan from the State Key Laboratory for Semiconductor Superlattice and Microstructures affiliated to the CAS Institute of Semiconductors has succeeded in developing a GaAs-based longwavelength laser device: InAs/GaAs self-assembly quantum dot laser with a wavelength of 1.33 μm under continuous-wave operation mode at room temperature. Experts say this is the most important achievement in the field of GaAsbased near-infrared, long-wavelength materials and devices in China in recent years.

  3. High-performance spinning device for DVD-based micromechanical signal transduction

    DEFF Research Database (Denmark)

    Hwu, En-Te; Chen, Ching-Hsiu; Bosco, Filippo;

    2013-01-01

    Here we report a high-throughput spinning device for nanometric scale measurements of microstructures with instrumentation details and experimental results. The readout technology implemented in the designed disc-like device is based on a DVD data storage optical pick-up unit (OPU). With a spinning...... robust and label-free bio-detection analysis of multiple compounds. The signal-to-noise ratio (S/N) is demonstrated from statistical measurements as 1.2 with arginine detection at 750 nM concentration. Practically, the OPU can measure up to 480 individual cantilever sensors per second with nanometer...

  4. Design of an online video edge detection device for bottle caps based on FPGA

    Directory of Open Access Journals (Sweden)

    Donghui LIU

    2015-06-01

    Full Text Available An online video edge detection device for bottle caps is designed and implemented using OV7670 video module and FPGA based control unit. By Verilog language programming, the device realizes the menu type parametric setting of the external VGA display, and completes the Roberts edge detection of real-time video image, which improves the speed of image processing. By improving the detection algorithm, the noise is effectively suppressed, and clear and coherent edge images are derived. The design improves the working environment, and avoids the harm to human body.

  5. A complementary electrochromic device based on polyaniline-tethered polyhedral oligomeric silsesquioxane and tungsten oxide

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Liying; Xiong, Shanxin; Ma, Jan; Lu, Xuehong [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2009-05-15

    In this paper we report a high-contrast complementary electrochromic device based on polyaniline-tethered polyhedral oligomeric silsesquioxane (POSS-PANI) and tungsten oxide (WO{sub 3}). The electrochromic properties, cyclic voltammetry behavior and coloration efficiency of the device are studied. Due to the loosely packed structure of POSS-PANI, it possesses more accessible doping sites and hence gives rise to a significantly higher electrochromic contrast than polyaniline (PANI). Furthermore, the replacement of PANI with POSS-PANI as the complementary layer for WO{sub 3} leads to an enhanced complementary effect, for which the underneath mechanism is also discussed. (author)

  6. Investigation of resistive switching behaviours in WO3-based RRAM devices

    Institute of Scientific and Technical Information of China (English)

    Li Ying-Tao; Liu Ming; Long Shi-Bing; Lü Hang-Bing; Liu Qi; Wang Qin; Wang Yan; Zhang Sen; Lian Wen-Tai; Liu Su

    2011-01-01

    In this paper, a WO3-based resistive random access memory device composed of a thin film of WO3 sandwiched between a copper top and a platinum bottom electrodes is fabricated by electron beam evaporation at room temperature.The reproducible resistive switching, low power consumption, multilevel storage possibility, and good data retention characteristics demonstrate that the Cu/WO3/Pt memory device is very promising for future nonvolatile memory applications. The formation and rupture of locaiised conductive filaments is suggested to be responsible for the observed resistive switching behaviours.

  7. Design and implementation of new sip-suction-online device based on ARM9

    International Nuclear Information System (INIS)

    In order to detect whether the nuclear fuel components are damaged when replacing them in the reactor of a nuclear power plant, a new sip-suction-online device is designed and introduced in this paper. The device is based on ARM9 processor, embedded linux operating system and Qt Embedded applications, with the functions of detection, display, control, alarm and storage. It can timely, accurately and reliably detect whether the nuclear fuel components are damaged in the environment of a nuclear power plant. (authors)

  8. Pattern recognition with TiOx-based memristive devices

    OpenAIRE

    Finn Zahari; Mirko Hansen; Thomas Mussenbrock; Martin Ziegler; Hermann Kohlstedt

    2015-01-01

    We report on the development of TiOx-based memristive devices for bio-inspired neuromorphic systems. In particular, capacitor like structures of Al/AlOx/TiOx/Al with, respectively 20 nm and 50 nm thick TiOx-layers were fabricated and analyzed in terms of their use in neural network circuits. Therefore, an equivalent circuit model is presented which mimics the observed device properties on a qualitative level and relies on mobile oxygen ions by taking electronic transport through local conduct...

  9. Design of an Optical Character Recognition System for Camera-based Handheld Devices

    CERN Document Server

    Mollah, Ayatullah Faruk; Basu, Subhadip; Nasipuri, Mita

    2011-01-01

    This paper presents a complete Optical Character Recognition (OCR) system for camera captured image/graphics embedded textual documents for handheld devices. At first, text regions are extracted and skew corrected. Then, these regions are binarized and segmented into lines and characters. Characters are passed into the recognition module. Experimenting with a set of 100 business card images, captured by cell phone camera, we have achieved a maximum recognition accuracy of 92.74%. Compared to Tesseract, an open source desktop-based powerful OCR engine, present recognition accuracy is worth contributing. Moreover, the developed technique is computationally efficient and consumes low memory so as to be applicable on handheld devices.

  10. Web content adaptation for mobile device: A fuzzy-based approach

    Directory of Open Access Journals (Sweden)

    Frank C.C. Wu

    2012-03-01

    Full Text Available While HTML will continue to be used to develop Web content, how to effectively and efficiently transform HTML-based content automatically into formats suitable for mobile devices remains a challenge. In this paper, we introduce a concept of coherence set and propose an algorithm to automatically identify and detect coherence sets based on quantified similarity between adjacent presentation groups. Experimental results demonstrate that our method enhances Web content analysis and adaptation on the mobile Internet.

  11. First principles design of divacancy defected graphene nanoribbon based rectifying and negative differential resistance device

    OpenAIRE

    Soubhik Chakrabarty; A. H. M. Abdul Wasey; Ranjit Thapa; Das, G. P.

    2015-01-01

    We have elaborately studied the electronic structure of 555-777 divacancy (DV) defected armchair edged graphene nanoribbon (AGNR) and transport properties of AGNR based two-terminal device constructed with one defected electrode and one N doped electrode, by using density functional theory and non-equilibrium Green's function based approach. The introduction of 555-777 DV defect into AGNRs, results in a shifting of the {\\pi} and {\\pi}* bands towards the higher energy value which indicates a s...

  12. Preprint Extending Touch-less Interaction on Vision Based Wearable Device

    OpenAIRE

    Lv, Zhihan; Feng, Liangbing; Feng, Shengzhong; Li, Haibo

    2015-01-01

    This is the preprint version of our paper on IEEE Virtual Reality Conference 2015. A touch-less interaction technology on vision based wearable device is designed and evaluated. Users interact with the application with dynamic hands/feet gestures in front of the camera. Several proof-of-concept prototypes with eleven dynamic gestures are developed based on the touch-less interaction. At last, a comparing user study evaluation is proposed to demonstrate the usability of the touch-less approach...

  13. Preprint Touch-less Interactive Augmented Reality Game on Vision Based Wearable Device

    OpenAIRE

    Lv, Zhihan; Halawani, Alaa; Feng, Shengzhong; Rehman, Shafiq Ur; Li, Haibo

    2015-01-01

    This is the preprint version of our paper on Personal and Ubiquitous Computing. There is an increasing interest in creating pervasive games based on emerging interaction technologies. In order to develop touch-less, interactive and augmented reality games on vision-based wearable device, a touch-less motion interaction technology is designed and evaluated in this work. Users interact with the augmented reality games with dynamic hands/feet gestures in front of the camera, which triggers the i...

  14. A new DRAM-type memory devices based on polymethacrylate containing pendant 2-methylbenzothiazole

    International Nuclear Information System (INIS)

    Graphical abstract: The devices fabricated with 75 nm and 45 nm thick pBVMA films were both found to exhibit DRAM type memory behaviors, which may indicate that the Al nanoparticles had no penetration into the thin film during the vacuum-deposition process. Highlights: ► The side-functional moieties of pBVMA regularly arranged in film state. ► The device exhibits volatile memory behavior with an ON/OFF current ratio up to 105. ► The film thickness has nothing to do with the device's memory behavior. ► Physical theoretical models and molecular simulation supported the memory mechanism. - Abstract: A polymethacrylate containing pendant 2-methylbenzothiazole (pBVMA) with good thermal stability was synthesized by free radical polymerization. The devices based on pBVMA possess a sandwich structure comprising bottom indium-tin oxide (ITO) electrode and top Al electrode. The as-fabricated device exhibits the dynamic random access memory (DRAM) behavior with an ON/OFF current ratio up to 105 and can endure 108 read cycles under −1 V pulse voltage. The effect of the film thickness on the device performance was investigated and the devices fabricated with 75 nm and 45 nm thick pBVMA films were both found to exhibit DRAM type memory behaviors, which may indicate that the Al nanoparticles had no penetration into the thin film during the vacuum-deposition process. The molecular simulation and physical theoretical models were analyzed and the mechanism of the DRAM performance may be attributed to the weak electron withdrawing ability of the molecule.

  15. Gapped Surface Plasmon Polariton Waveguide Device Based on a Liquid Crystal.

    Science.gov (United States)

    Lee, Dong Hun; Lee, Myung-Hyun

    2015-10-01

    We propose a gapped surface plasmon polariton waveguide (G-SPPW) device based on a liquid crystal (LC) at a wavelength of 1.55 μm. The G-SPPW device is composed of an input 2.0-μm-wide and 5.0-μm-long insulator-metal-insulator waveguide (IMI-W), an 8-μm-long gap, and an output 2.0-μm-wide and 25.0-μm-long IMI-W. The LC is used for the gap and the 5.15-μm-thick upper and lower dielectric layers. The input surface plasmon polaritons (SPPs) propagate and jump over the gap in the G-SPPW with a coupling loss of less than ~0.68 dB. The propagation and coupling losses of the 38-μm-long G-SPPW device are varied in the range of ~0.5268 dB to ~2.6716 dB and ~0.1446 dB to ~0.6784 dB, respectively, with LC tilt angles (θ1,2) = 0°~90° at a fixed 90° twist angle. The normalized transmission of the G-SPPW device is also varied in the range from -3.351 dB to -0.6714 dB with θ1,2 = 0°~90° at a fixed 90° twist angle. The output SPP characteristics of the G-SPPW device can be properly controlled by the orientation of the LC molecules. The proposed G-SPPW device shows potential for new active plasmonic device applications. PMID:26726399

  16. Hydrazine-based deposition route for device-quality CIGS films

    International Nuclear Information System (INIS)

    A simple solution-based approach for depositing CIGS (Cu-In-Ga-Se/S) absorber layers is discussed, with an emphasis on film characterization, interfacial properties and integration into photovoltaic devices. The process involves incorporating all metal and chalcogenide components into a single hydrazine-based solution, spin coating a precursor film, and heat treating in an inert atmosphere, to form the desired CIGS film with up to micron-scaled film thickness and grain size. PV devices (glass/Mo/CIGS/CdS/i-ZnO/ITO) employing the spin-coated CIGS and using processing temperatures below 500 deg. C have yielded power conversion efficiencies of up to 10% (AM 1.5 illumination), without the need for a post-CIGS-deposition treatment in a gaseous Se source or a cyanide-based bath etch. Short-duration low-temperature (T < 200 deg. C ) oxygen treatment of completed devices is shown to have a positive impact on the performance of initially underperforming cells, thereby enabling better performance in devices prepared at temperatures below 500 deg. C

  17. Multilayer soft lithography of perfluoropolyether based elastomer for microfluidic device fabrication.

    Science.gov (United States)

    Devaraju, Naga Sai Gopi Krishna; Unger, Marc Alexander

    2011-06-01

    The compatibility of microfluidic devices with solvents and other chemicals is extremely important for many applications such as organic synthesis in microreactors and drug screening. We report the successful fabrication of microfluidic devices from a novel perfluoropolyether based polymer utilizing the Multilayer Soft Lithography™ (MSL) technique with simple, straightforward processing. The perfluorinated polymer SIFEL X-71 8115 is a highly chemically resistant elastomeric material. We demonstrate fabrication of a microfluidic device using an off-ratio bonding technique to bond multiple SIFEL layers, each patterned lithographically. The mechanical properties of the SIFEL MSL valves (including actuation pressures) are similar to PDMS MSL valves of the same geometry. Chemical compatibility tests highlight SIFEL's remarkable resistance to organic solvents, acids and alkalis. PMID:21503367

  18. Flexible electrochromic device based on poly (3,4-(2,2-dimethylpropylenedioxy)thiophene)

    Energy Technology Data Exchange (ETDEWEB)

    Ma Chao; Taya, Minoru [Center of Intelligent Materials and Systems, University of Washington, Box 352600, Seattle, WA 98195 (United States); Xu Chunye [Center of Intelligent Materials and Systems, University of Washington, Box 352600, Seattle, WA 98195 (United States)], E-mail: Chunye@u.washington.edu

    2008-12-30

    In this study, the design, fabrication and characterization of a flexible electrochromic device based on indium tin oxide (ITO) coated polyethylene terephthalate (PET) plastic is discussed. The working electrochromic material film was poly (3,4-(2,2-dimethylpropylenedioxy)thiophene) (PProDOT-Me{sub 2}), while the counter layer of the device was vanadium oxide titanium oxide (V{sub 2}O{sub 5}/TiO{sub 2}) composite film, which serves as an ion storage layer. A solution type electrolyte was used as the ionic transport layer and was sandwiched between the working and counter layers. The device exhibited tuneable light transmittance between transparent and deep blue color, with a maximum contrast ratio at 580 nm wavelength. Other important properties, such as switching speed, life time, and coloration efficiency have been improved.

  19. A device model framework for magnetoresistive sensors based on the Stoner–Wohlfarth model

    International Nuclear Information System (INIS)

    The Stoner–Wohlfarth (SW) model provides an efficient analytical model to describe the behavior of magnetic layers within magnetoresistive sensors. Combined with a proper description of magneto-resistivity an efficient device model can be derived, which is necessary for an optimal electric circuit design. Parameters of the model are determined by global optimization of an application specific cost function which contains measured resistances for different applied fields. Several application cases are examined and used for validation of the device model. - Highlights: • An efficient device model framework for various types of magnetoresistive sensors is presented. • The model is based on the analytical solution of the Stoner–Wohlfarth model. • Numerical optimization methods provide optimal model parameters for a different application cases. • The model is applied to several application cases and is able to reproduce measured hysteresis and swiching behavior

  20. Light emitting devices based on Si nanoclusters: the integration with a photonic crystal and electroluminescence properties

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We present the properties and potentialities of light emitting devices based on amorphous Si nanoclusters. Amorphous nanostructures may constitute an interesting alternative to Si nanocrystals for the monolithic integration of optical and electrical functions in Si technology. In fact, they exhibit an intense room temperature electroluminescence (EL). The EL properties of these devices have been studied as a function of current and of temperature. Moreover, to improve the extraction efficiency of the light, we have integrated the emitting system with a 2D photonic crystal structure opportunely fabricated by using conventional optical lithography to reduce the total internal reflection of the emitted light. The extraction efficiency in such devices increases by a factor of 4 at a resonance wavelength.