Topologically-protected one-way leaky waves in nonreciprocal plasmonic structures

Science.gov (United States)

Hassani Gangaraj, S. Ali; Monticone, Francesco

2018-03-01

We investigate topologically-protected unidirectional leaky waves on magnetized plasmonic structures acting as homogeneous photonic topological insulators. Our theoretical analyses and numerical experiments aim at unveiling the general properties of these exotic surface waves, and their nonreciprocal and topological nature. In particular, we study the behavior of topological leaky modes in stratified structures composed of a magnetized plasma at the interface with isotropic conventional media, and we show how to engineer their propagation and radiation properties, leading to topologically-protected backscattering-immune wave propagation, and highly directive and tunable radiation. Taking advantage of the non-trivial topological properties of these leaky modes, we also theoretically demonstrate advanced functionalities, including arbitrary re-routing of leaky waves on the surface of bodies with complex shapes, as well as the realization of topological leaky-wave (nano)antennas with isolated channels of radiation that are completely independent and separately tunable. Our findings help shedding light on the behavior of topologically-protected modes in open wave-guiding structures, and may open intriguing directions for future antenna generations based on topological structures, at microwaves and optical frequencies.

Design of apron feeders

Energy Technology Data Exchange (ETDEWEB)

Ramos, C.M.

1987-12-01

This paper discusses practical aspects of apron feeder design, and includes information on how to make the first selection. Various aspects of design such as feeder speed, material depth, chain-pitch, roller loading, wheels/sprockets and chain roller friction are elaborated in detail. 8 refs., 14 figs., 12 tabs.

Simpson's Paradox in the Interpretation of "Leaky Pipeline" Data

Science.gov (United States)

Walton, Paul H.; Walton, Daniel J.

2016-01-01

The traditional "leaky pipeline" plots are widely used to inform gender equality policy and practice. Herein, we demonstrate how a statistical phenomenon known as Simpson's paradox can obscure trends in gender "leaky pipeline" plots. Our approach has been to use Excel spreadsheets to generate hypothetical "leaky…

The development and manufacture of size for size feeder pipe for feeder replacement

International Nuclear Information System (INIS)

Legate, G.; Schreiter, D.; Townley, N.

2008-01-01

The recently recognised problem of feeder pipe thinning created a unique sourcing problem. Operators require relatively small quantities of nuclear class 1 seamless feeder pipe for such replacement which prior to the introduction of this product in 2006 was not available. It was desired that the pipe be produced at the exact size of the pipe currently in use at the specific reactor site (feeder pipe size varies from site to site). Secondly the pipe had to be made in conformance to the original code year of issue and to conform to the intent of the original material specifications. Finally a supply strategy had to be implemented allowing for timely manufacture of replacement piping. This presentation will report upon how replacement size for size feeder tube was developed and is currently manufactured at Nu-Tech Precision Metals. The paper will also detail the current supply strategy to ensure timely manufacture of the product.

Modeling and analysis of power extraction circuits for passive UHF RFID applications

International Nuclear Information System (INIS)

Fan Bo; Dai Yujie; Zhang Xiaoxing; Lue Yingjie

2009-01-01

Modeling and analysis of far field power extraction circuits for passive UHF RF identification (RFID) applications are presented. A mathematical model is derived to predict the complex nonlinear performance of UHF voltage multiplier using Schottky diodes. To reduce the complexity of the proposed model, a simple linear approximation for Schottky diode is introduced. Measurement results show considerable agreement with the values calculated by the proposed model. With the derived model, optimization on stage number for voltage multiplier to achieve maximum power conversion efficiency is discussed. Furthermore, according to the Bode-Fano criterion and the proposed model, a limitation on maximum power up range for passive UHF RFID power extraction circuits is also studied.

Analysis and Synthesis of Leaky-Wave Devices in Planar Technology

Science.gov (United States)

Martinez Ros, Alejandro Javier

The work developed along this doctoral thesis has been focused on the analysis and synthesis of microwave devices in planar technology. In particular, several types of devices based on the radiation mechanism of leaky waves have been studied. Typically, the radiation properties in leaky-wave devices are determined by the complex propagation constant of the leaky mode, wherein the phase constant is responsible for the pointing angle and the leakage rate for the intensity of the radiated fields. In this manner, by controlling both amplitude and phase of the leaky mode, an effective control over the device's radiation diagram can be obtained. Moreover, with the purpose of efficiently obtaining the leaky mode's radiation properties as function of the main geometrical parameters of the structure, several modal tools based on the transverse resonance analysis of the structure have been performed. In order to demonstrate this simultaneous control over the complex propagation constant in planar technology, several types of leaky-wave devices, including antennas (LWAs), multiplexors and near-field focusing systems, have been designed and manufactured in the technology of substrate integrated waveguide (SIW). This recently proposed technology, allows the design of devices based on classical waveguide technology with standard manufacturing techniques used for printed circuit board (PCB) designs. In this way, most of the parts that form a communication system can be integrated into a single substrate, thus reducing its cost and providing a more robust and compact device, which has less losses compared to other planar technologies such as the microstrip. El trabajo llevado a cabo durante la realizacion de esta tesis doctoral, se ha centrado en el analisis y sintesis de dispositivos de microondas en tecnologia planar. En concreto, se han estudiado diferentes tipos de dispositivos basados en radiacion por ondas de fuga "leaky waves", en los cuales las propiedades de radiacion

Experimental Investigation on Propagation Characteristics of PD Radiated UHF Signal in Actual 252 kV GIS

Directory of Open Access Journals (Sweden)

Tianhui Li

2017-07-01

Full Text Available For partial discharge (PD diagnostics in gas insulated switchgears (GISs based on the ultra-high-frequency (UHF method, it is essential to study the attenuation characteristics of UHF signals so as to improve the application of the UHF technique. Currently, the performance of UHF has not been adequately considered in most experimental research, while the constructive conclusions about the installation and position of UHF sensors are relatively rare. In this research, by using a previously-designed broadband sensor, the output signal is detected and analyzed experimentally in a 252 kV GIS with L-shaped structure and disconnecting switch. Since the relative position of the sensor and the defect is usually fixed by prior research, three circumferential angle positions of the defect in cross section are performed. The results are studied by time, statistics and frequency analyses. This identifies that the discontinuity conductor of DS will lead to a rise of both the peak to peak value (Vpp and the transmission rate of the UHF signal. Then, the frequency analysis indicates that the reason for the distinction of signal amplitude and transmission rate is that the mode components of the PD signal are distinctively affected by the special structure of GIS. Finally, the optimal circumferential angle position of the UHF Sensor is given based on the comparison of transmission rates.

Dynamic stability analysis of fractional order leaky integrator echo state neural networks

Science.gov (United States)

Pahnehkolaei, Seyed Mehdi Abedi; Alfi, Alireza; Tenreiro Machado, J. A.

2017-06-01

The Leaky integrator echo state neural network (Leaky-ESN) is an improved model of the recurrent neural network (RNN) and adopts an interconnected recurrent grid of processing neurons. This paper presents a new proof for the convergence of a Lyapunov candidate function to zero when time tends to infinity by means of the Caputo fractional derivative with order lying in the range (0, 1). The stability of Fractional-Order Leaky-ESN (FO Leaky-ESN) is then analyzed, and the existence, uniqueness and stability of the equilibrium point are provided. A numerical example demonstrates the feasibility of the proposed method.

Simpson’s Paradox in the interpretation of “leaky pipeline” data

Directory of Open Access Journals (Sweden)

Walton Paul H.

2016-12-01

Full Text Available The traditional ‘leaky pipeline’ plots are widely used to inform gender equality policy and practice. Herein, we demonstrate how a statistical phenomenon known as Simpson’s paradox can obscure trends in gender ‘leaky pipeline’ plots. Our approach has been to use Excel spreadsheets to generate hypothetical ‘leaky pipeline’ plots of gender inequality within an organisation. The principal factors, which make up these hypothetical plots, can be input into the model so that a range of potential situations can be modelled. How the individual principal factors are then reflected in ‘leaky pipeline’ plots is shown. We find that the effect of Simpson’s paradox on leaky pipeline plots can be simply and clearly illustrated with the use of hypothetical modelling and our study augments the findings in other statistical reports of Simpson’s paradox in clinical trial data and in gender inequality data. The findings in this paper, however, are presented in a way, which makes the paradox accessible to a wide range of people.

A bend thickness sensitivity study of Candu feeder piping

International Nuclear Information System (INIS)

Li, M.; Aggarwal, M.L.; Meysner, A.; Micelotta, C.

2005-01-01

In CANDU reactors, feeder bends close to the connection at the fuel channel may be subjected to the highest Flow Accelerated Corrosion (FAC) and stresses. Feeder pipe stress analysis is crucial in the life extension of aging CANDU plants. Typical feeder pipes are interconnected by upper link plates and spacers. It is well known that the stresses at the bends are sensitive to the local bend thicknesses. It is also known from the authors' study (Li and et al, 2005) that feeder inter linkage effect is significant and cannot be ignored. The field measurement of feeder bend thickness is difficult and may be subjected to uncertainty in accuracy. Hence, it is desirable to know how the stress on a subject feeder could be affected by the bend thickness variation of the neighboring feeders. This effect cannot be evaluated by the traditional 'single' feeder model approach. In this paper, the 'row' and 'combined' models developed in the previous study (Li and et al, 2005), which include the feeder interactions, are used to investigate the sensitivity of bend thickness. A series of random thickness bounded by maximum and minimum measured values were applied to feeders in the model. The results show that an individual feeder is not sensitive to the bend thickness variation of the remaining feeders in the model, but depends primarily on its own bend thickness. The highest stress at a feeder always occurs when the feeder has the smallest possible bend thickness. A minimum acceptable bend thickness for individual feeders can be computed by an iterative computing process. The dependency of field thickness measurement and the amount of required analysis work can be greatly reduced. (authors)

Ionospheric Impacts on UHF Space Surveillance

Science.gov (United States)

Jones, J. C.

2017-12-01

Earth's atmosphere contains regions of ionized plasma caused by the interaction of highly energetic solar radiation. This region of ionization is called the ionosphere and varies significantly with altitude, latitude, local solar time, season, and solar cycle. Significant ionization begins at about 100 km (E layer) with a peak in the ionization at about 300 km (F2 layer). Above the F2 layer, the atmosphere is mostly ionized but the ion and electron densities are low due to the unavailability of neutral molecules for ionization so the density decreases exponentially with height to well over 1000 km. The gradients of these variations in the ionosphere play a significant role in radio wave propagation. These gradients induce variations in the index of refraction and cause some radio waves to refract. The amount of refraction depends on the magnitude and direction of the electron density gradient and the frequency of the radio wave. The refraction is significant at HF frequencies (3-30 MHz) with decreasing effects toward the UHF (300-3000 MHz) range. UHF is commonly used for tracking of space objects in low Earth orbit (LEO). While ionospheric refraction is small for UHF frequencies, it can cause errors in range, azimuth angle, and elevation angle estimation by ground-based radars tracking space objects. These errors can cause significant errors in precise orbit determinations. For radio waves transiting the ionosphere, it is important to understand and account for these effects. Using a sophisticated radio wave propagation tool suite and an empirical ionospheric model, we calculate the errors induced by the ionosphere in a simulation of a notional space surveillance radar tracking objects in LEO. These errors are analyzed to determine daily, monthly, annual, and solar cycle trends. Corrections to surveillance radar measurements can be adapted from our simulation capability.

Environmental/Noise Effects on VHF/UHF UWB SAR

National Research Council Canada - National Science Library

Ralston, James

1998-01-01

This paper presents a straightforward approach to estimating the impact of natural environmental noise on an overall system noise temperature for very high frequency/ultrahigh frequency synthetic aperture radar (VHF/UHF SAR...

Leaky Gut As a Danger Signal for Autoimmune Diseases

Directory of Open Access Journals (Sweden)

Qinghui Mu

2017-05-01

Full Text Available The intestinal epithelial lining, together with factors secreted from it, forms a barrier that separates the host from the environment. In pathologic conditions, the permeability of the epithelial lining may be compromised allowing the passage of toxins, antigens, and bacteria in the lumen to enter the blood stream creating a “leaky gut.” In individuals with a genetic predisposition, a leaky gut may allow environmental factors to enter the body and trigger the initiation and development of autoimmune disease. Growing evidence shows that the gut microbiota is important in supporting the epithelial barrier and therefore plays a key role in the regulation of environmental factors that enter the body. Several recent reports have shown that probiotics can reverse the leaky gut by enhancing the production of tight junction proteins; however, additional and longer term studies are still required. Conversely, pathogenic bacteria that can facilitate a leaky gut and induce autoimmune symptoms can be ameliorated with the use of antibiotic treatment. Therefore, it is hypothesized that modulating the gut microbiota can serve as a potential method for regulating intestinal permeability and may help to alter the course of autoimmune diseases in susceptible individuals.

A Numerical Estimation of a RFID Reader Field and SAR inside a Blood Bag at UHF

Directory of Open Access Journals (Sweden)

Alessandro Fanti

2016-11-01

Full Text Available In this paper, the effects of UHF electromagnetic fields produced by a RFID reader on a blood bag are evaluated numerically in several configurations. The results of the simulation, field level and distribution, specific absorption rate (SAR, and heating time show that an exposure to a typical reader field leads to a temperature increase smaller than 0.1 C and to a SAR smaller than 1 W/kg. As a consequence, no adverse biological effects occur during a typical UHF RFID reading cycle on a blood bag. Therefore, the blood contained in a bag traced using UHF-RFID is as safe as those traced using barcodes. The proposed analysis supports the use of UHF RFID in the blood transfusion supply chain.

The Anti-RFI Design of Intelligent Electric Energy Meters with UHF RFID

Science.gov (United States)

Chen, Xiangqun; Huang, Rui; Shen, Liman; chen, Hao; Xiong, Dezhi; Xiao, Xiangqi; Liu, Mouhai; Xu, Renheng

2018-03-01

In order to solve the existing artificial meter reading watt-hour meter industry is still slow and inventory of common problems, using the uhf radio frequency identification (RFID) technology and intelligent watt-hour meter depth fusion, which has a one-time read multiple tags, identification distance, high transmission rate, high reliability, etc, while retaining the original asset management functions, in order to ensure the uhf RFID and minimum impact on the operation of the intelligent watt-hour meter, proposed to improve the stability of the electric meter system while working at the same time, this paper designs the uhf RFID intelligent watt-hour meter radio frequency interference resistance, put forward to improve intelligent watt-hour meter electromagnetic compatibility design train of thought, and introduced its power and the hardware circuit design of printed circuit board, etc.

A study of inter linkage effects on Candu feeder piping

International Nuclear Information System (INIS)

Li, M.; Aggarwal, M.L.; Meysner, A.

2005-01-01

A CANDU (Canadian Deuterium Uranium) reactor core consists of a large number of fuel channels where heat is generated. Two feeder pipes are connected to each fuel channel to transport D 2 O coolant into and out of the reactor core. The feeder piping is designed to the requirements of Class 1 piping of Section III NB of the ASME Boiler and Pressure Vessel and CSA Codes. Feeder piping stress analysis is being performed to demonstrate the code compliance check and the fitness for service of feeders. In the past, stress analyses were conducted for each individual feeder without including interaction effects among connected feeders. Interaction effects occur as a result of linkages that exist between feeders to prevent fretting and impacting damage during normal, abnormal and accident conditions. In this paper, a 'combined' approach is adopted to include all feeders connected by inter linkages into one feeder piping model. MSC/NASTRAN finite element software was used in the stress simulation, which contains up to 127 feeder pipes. The ASME Class 1 piping analysis was conducted to investigate the effects of the linkages between feeders. Both seismic time history and broadened response spectra methods were used in the seismic stress calculation. The results show that the effect of linkages is significant in dynamic stresses for all feeder configurations, as well as in static stresses for certain feeder configurations. The single feeder analysis could either underestimate or overestimate feeder stresses depending on the pipe geometry and bend wall thickness. (authors)

The Ultrawideband Leaky Lens Antenna

NARCIS (Netherlands)

Bruni, S.; Neto, A.; Marliani, F.

2007-01-01

A novel directive and nondispersive antenna is presented: the ultrawideband (UWB) leaky lens. It is based on the broad band Cherenkov radiation occurring at a slot printed between different infinite homogeneous dielectrics. The first part of the paper presents the antenna concept and the UWB design.

A Broadband UHF Tag Antenna For Near-Field and Far-Field RFID Communications

Directory of Open Access Journals (Sweden)

M. Dhaouadi

2014-12-01

Full Text Available The paper deals with the design of passive broadband tag antenna for Ultra-High Frequency (UHF band. The antenna is intended for both near and far fields Radio Frequency Identification (RFID applications. The meander dipole tag antenna geometry modification is designed for frequency bandwidth increasing. The measured bandwidth of the proposed broadband Tag antenna is more than 140 MHz (820–960 MHz, which can cover the entire UHF RFID band. A comparison between chip impedance of datasheet and the measured chip impedance has been used in our simulations. The proposed progressive meandered antenna structure, with an overall size of 77 mm × 14 mm × 0.787 mm, produces strong and uniform magnetic field distribution in the near-field zone. The antenna impedance is matched to common UHF chips in market simply by tuning its capacitive and inductive values since a perfect matching is required in the antenna design in order to enhance the near and the far field communications. Measurements confirm that the designed antenna exhibits good performance of Tag identification for both near-field and far-field UHF RFID applications.

Development of dry coal feeders

Science.gov (United States)

Bonin, J. H.; Cantey, D. E.; Daniel, A. D., Jr.; Meyer, J. W.

1977-01-01

Design and fabrication of equipment of feed coal into pressurized environments were investigated. Concepts were selected based on feeder system performance and economic projections. These systems include: two approaches using rotating components, a gas or steam driven ejector, and a modified standpipe feeder concept. Results of development testing of critical components, design procedures, and performance prediction techniques are reviewed.

Economic feeder for recharging and ``topping off''

Science.gov (United States)

Fickett, Bryan; Mihalik, G.

2000-04-01

Increasing the size of the melt charge significantly increases yield and reduces costs. Siemens Solar Industries is optimizing a method to charge additional material after meltdown (top-off) using an external feeder system. A prototype feeder system was fabricated consisting of a hopper and feed delivery system. The low-cost feeder is designed for simple operation and maintenance. The system is capable of introducing up to 60 kg of granular silicon while under vacuum. An isolation valve permits refilling of the hopper while maintaining vacuum in the growth furnace. Using the feeder system in conjunction with Siemens Solar Industries' energy efficient hot zone dramatically reduces power and argon consumption. Throughput is also improved as faster pull speeds can be attained. The increased pull speeds have an even greater impact when the charge size is increased. Further cost reduction can be achieved by refilling the crucible after crystal growth and pulling a second ingot run. Siemens Solar Industries is presently testing the feeder in production.

Human induced pluripotent stem cells on autologous feeders.

Directory of Open Access Journals (Sweden)

Kazutoshi Takahashi

Full Text Available BACKGROUND: For therapeutic usage of induced Pluripotent Stem (iPS cells, to accomplish xeno-free culture is critical. Previous reports have shown that human embryonic stem (ES cells can be maintained in feeder-free condition. However, absence of feeder cells can be a hostile environment for pluripotent cells and often results in karyotype abnormalities. Instead of animal feeders, human fibroblasts can be used as feeder cells of human ES cells. However, one still has to be concerned about the existence of unidentified pathogens, such as viruses and prions in these non-autologous feeders. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that human induced Pluripotent Stem (iPS cells can be established and maintained on isogenic parental feeder cells. We tested four independent human skin fibroblasts for the potential to maintain self-renewal of iPS cells. All the fibroblasts tested, as well as their conditioned medium, were capable of maintaining the undifferentiated state and normal karyotypes of iPS cells. Furthermore, human iPS cells can be generated on isogenic parental fibroblasts as feeders. These iPS cells carried on proliferation over 19 passages with undifferentiated morphologies. They expressed undifferentiated pluripotent cell markers, and could differentiate into all three germ layers via embryoid body and teratoma formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that autologous fibroblasts can be not only a source for iPS cells but also be feeder layers. Our results provide a possibility to solve the dilemma by using isogenic fibroblasts as feeder layers of iPS cells. This is an important step toward the establishment of clinical grade iPS cells.

Inkjet printing of UHF antennas on corrugated cardboards for packaging applications

Energy Technology Data Exchange (ETDEWEB)

Sowade, Enrico, E-mail: enrico.sowade@mb.tu-chemnitz.de [Digital Printing and Imaging Technology, Technische Universität Chemnitz, Chemnitz (Germany); Göthel, Frank [Digital Printing and Imaging Technology, Technische Universität Chemnitz, Chemnitz (Germany); Zichner, Ralf [Department Printed Functionalities, Fraunhofer Institute for Electronic Nano Systems (ENAS), Chemnitz (Germany); Baumann, Reinhard R. [Digital Printing and Imaging Technology, Technische Universität Chemnitz, Chemnitz (Germany); Department Printed Functionalities, Fraunhofer Institute for Electronic Nano Systems (ENAS), Chemnitz (Germany)

2015-03-30

Highlights: • Inkjet printing of UHF antennas on cardboard substrates. • Development of primer layer to compensate the absorptiveness of the cardboard and the rough surface. • Manufacturing of UHF antennas in a fully digital manner for packaging applications. - Abstract: In this study, a method based on inkjet printing has been established to develop UHF antennas on a corrugated cardboard for packaging applications. The use of such a standardized, paper-based packaging substrate as material for printing electronics is challenging in terms of its high surface roughness and high ink absorption rate, especially when depositing very thin films with inkjet printing technology. However, we could obtain well-defined silver layers on the cardboard substrates due to a primer layer approach. The primer layer is based on a UV-curable ink formulation and deposited as well as the silver ink with inkjet printing technology. Industrial relevant printheads were chosen for the deposition of the materials. The usage of inkjet printing allows highest flexibility in terms of pattern design. The primer layer was proven to optimize the surface characteristics of the substrate, mainly reducing the surface roughness and water absorptiveness. Thanks to the primer layer approach, ultra-high-frequency (UHF) radio-frequency identification (RFID) antennas were deposited by inkjet printing on the corrugated cardboards. Along with the characterization and interpretation of electrical properties of the established conductive antenna patterns, the performance of the printed antennas were analyzed in detail by measuring the scattering parameter S{sub 11} and the antenna gain.

An RFID Based Smart Feeder for Hummingbirds.

Science.gov (United States)

Ibarra, Vicente; Araya-Salas, Marcelo; Tang, Yu-ping; Park, Charlie; Hyde, Anthony; Wright, Timothy F; Tang, Wei

2015-12-16

We present an interdisciplinary effort to record feeding behaviors and control the diet of a hummingbird species (Phaethornis longirostris, the long-billed hermit or LBH) by developing a Radio Frequency Identification (RFID) based smart feeder. The system contains an RFID reader, a microcontroller, and a servo-controlled hummingbird feeder opener; the system is presented as a tool for studying the cognitive ability of the LBH species. When equipped with glass capsule RFID tags (which are mounted on the hummingbird), the smart feeder can provide specific diets for predetermined sets of hummingbirds at the discretion of biologists. This is done by reading the unique RFID tag on the hummingbirds and comparing the ID number with the pre-programmed ID numbers stored in the smart feeder. The smart feeder records the time and ID of each hummingbird visit. The system data is stored in a readily available SD card and is powered by two 9 V batteries. The detection range of the system is approximately 9-11 cm. Using this system, biologists can assign the wild hummingbirds to different experimental groups and monitor their diets to determine if they develop a preference to any of the available nectars. During field testing, the smart feeder system has demonstrated consistent detection (when compared to detections observed by video-recordings) of RFID tags on hummingbirds and provides pre-designed nectars varying water and sugar concentrations to target individuals. The smart feeder can be applied to other biological and environmental studies in the future.

An RFID Based Smart Feeder for Hummingbirds

Directory of Open Access Journals (Sweden)

Vicente Ibarra

2015-12-01

Full Text Available We present an interdisciplinary effort to record feeding behaviors and control the diet of a hummingbird species (Phaethornis longirostris, the long-billed hermit or LBH by developing a Radio Frequency Identification (RFID based smart feeder. The system contains an RFID reader, a microcontroller, and a servo-controlled hummingbird feeder opener; the system is presented as a tool for studying the cognitive ability of the LBH species. When equipped with glass capsule RFID tags (which are mounted on the hummingbird, the smart feeder can provide specific diets for predetermined sets of hummingbirds at the discretion of biologists. This is done by reading the unique RFID tag on the hummingbirds and comparing the ID number with the pre-programmed ID numbers stored in the smart feeder. The smart feeder records the time and ID of each hummingbird visit. The system data is stored in a readily available SD card and is powered by two 9 V batteries. The detection range of the system is approximately 9–11 cm. Using this system, biologists can assign the wild hummingbirds to different experimental groups and monitor their diets to determine if they develop a preference to any of the available nectars. During field testing, the smart feeder system has demonstrated consistent detection (when compared to detections observed by video-recordings of RFID tags on hummingbirds and provides pre-designed nectars varying water and sugar concentrations to target individuals. The smart feeder can be applied to other biological and environmental studies in the future.

Compact broadband circularly polarised slot antenna for universal UHF RFID readers

DEFF Research Database (Denmark)

Xu, Bo; Zhang, Shuai; Liu, Yusha

2015-01-01

A compact broadband circularly polarised (CP) slot antenna is designed for universal ultra-high-frequency (UHF) radio frequency identification (RFID) readers. The antenna consists of an L-shaped metal strip and a square-slot-loaded ground plane with four tuning stubs. The total size is 100 mm×100mm......×1.6 mm. The measured –10 dB impedance bandwidth is 40.7% (772–1166 MHz) and the measured 3 dB axial ratio (AR) bandwidth is 13.9% (840–965 MHz). Both the impedance and AR bandwidth cover the worldwide UHF RFID band....

SAFIRE - a robotic inspection system for CANDU feeders

Energy Technology Data Exchange (ETDEWEB)

Buckingham, R. [OC Robotics, Bristol (United Kingdom)

2011-07-01

The condition of primary circuit feeder pipes in CANDU reactors is relevant to the commercial viability and plant life. One known wear mechanism is external fretting between feeder pipes and adjacent services or support structures, particularly within the Upper Feeder Cabinet (UFC). Fretting leads to wall thinning which must not exceed certain agreed limits. Chafe shields have been added to protect the feeder pipes. Regular inspections are required of the chafe shields, feeder pipes and other structures that may cause feeder damage. Historically, the dose received by inspectors conducting this work has been significant. For this reason Ontario Power Generation has invested in a remotely operated robot system to conduct visual inspections within the UFC. This system, called SAFIRE for 'Snake-Arm Feeder Inspection Robot Equipment' has been deployed at Pickering during 2010 and 2011 and has been used to inspect areas that are extremely difficult to inspect with existing manual techniques. The 2011 scope of work included inspection of a total of 660 feeder pipes in three UFC quadrants, in two reactors. The full scope was completed over a one-month period in Autumn 2011 in which SAFIRE was used during 23, twelve hour shifts. This included two periods each of 72 hours of continuous operation using multiple teams of operators. SAFIRE is remote controlled delivery system for multiple cameras to record still images and video. The main system elements include a snake-arm robot mounted on a mobile vehicle. It can be controlled from up to 500m away using a fibre/copper connection. The snake-arm is 2.2m long, 25mm wide and has 18 degrees of freedom. It is designed to snake between the rows of feeder pipes to inspect feeder/hanger interfaces, both above and below the feeder cabinet catwalks. Future upgrades offer the potential to add additional tools to increase functionality. This paper describes the SAFIRE development process from inception to operational experience

SAFIRE - a robotic inspection system for CANDU feeders

International Nuclear Information System (INIS)

Buckingham, R.

2011-01-01

The condition of primary circuit feeder pipes in CANDU reactors is relevant to the commercial viability and plant life. One known wear mechanism is external fretting between feeder pipes and adjacent services or support structures, particularly within the Upper Feeder Cabinet (UFC). Fretting leads to wall thinning which must not exceed certain agreed limits. Chafe shields have been added to protect the feeder pipes. Regular inspections are required of the chafe shields, feeder pipes and other structures that may cause feeder damage. Historically, the dose received by inspectors conducting this work has been significant. For this reason Ontario Power Generation has invested in a remotely operated robot system to conduct visual inspections within the UFC. This system, called SAFIRE for 'Snake-Arm Feeder Inspection Robot Equipment' has been deployed at Pickering during 2010 and 2011 and has been used to inspect areas that are extremely difficult to inspect with existing manual techniques. The 2011 scope of work included inspection of a total of 660 feeder pipes in three UFC quadrants, in two reactors. The full scope was completed over a one-month period in Autumn 2011 in which SAFIRE was used during 23, twelve hour shifts. This included two periods each of 72 hours of continuous operation using multiple teams of operators. SAFIRE is remote controlled delivery system for multiple cameras to record still images and video. The main system elements include a snake-arm robot mounted on a mobile vehicle. It can be controlled from up to 500m away using a fibre/copper connection. The snake-arm is 2.2m long, 25mm wide and has 18 degrees of freedom. It is designed to snake between the rows of feeder pipes to inspect feeder/hanger interfaces, both above and below the feeder cabinet catwalks. Future upgrades offer the potential to add additional tools to increase functionality. This paper describes the SAFIRE development process from inception to operational experience gained

Increased operational range for implantable UHF RFID antennas

NARCIS (Netherlands)

Dubok, A.; Smolders, A.B.

2014-01-01

This paper discusses the main design challenges of implantable UHF RFID antennas in lossy environments. A novel cylindrical implantable antenna concept is presented. The proposed antenna shows good performance inside lossy environments, like a human body. The RFID tag is able to work in a range up

Focusing Leaky Waves: A Class of Electromagnetic Localized Waves with Complex Spectra

Science.gov (United States)

Fuscaldo, Walter; Comite, Davide; Boesso, Alessandro; Baccarelli, Paolo; Burghignoli, Paolo; Galli, Alessandro

2018-05-01

Localized waves, i.e., the wide class of limited-diffraction, limited-dispersion solutions to the wave equation are generally characterized by real wave numbers. We consider the role played by localized waves with generally complex "leaky" wave numbers. First, the impact of the imaginary part of the wave number (i.e., the leakage constant) on the diffractive (spatial broadening) features of monochromatic localized solutions (i.e., beams) is rigorously evaluated. Then general conditions are derived to show that only a restricted class of spectra (either real or complex) allows for generating a causal localized wave. It turns out that backward leaky waves fall into this category. On this ground, several criteria for the systematic design of wideband radiators, namely, periodic radial waveguides based on backward leaky waves, are established in the framework of leaky-wave theory. An effective design method is proposed to minimize the frequency dispersion of the proposed class of devices and the impact of the "leakage" on the dispersive (temporal broadening) features of polychromatic localized solutions (i.e., pulses) is accounted for. Numerical results corroborate the concept, clearly highlighting the advantages and limitations of the leaky-wave approach for the generation of localized pulses at millimeter-wave frequencies, where energy focusing is in high demand in modern applications.

Risk-informed prediction of feeder end of life

International Nuclear Information System (INIS)

Jyrkama, M.; Pandey, M.

2011-01-01

The operating life of feeder piping is negatively impacted by flow accelerated corrosion (FAC). In this study, an assessment of a large set of inspection data reveals that FAC in feeders is a relatively stationary process, with variability only at the local scale. Given the added uncertainty from inspection coverage, a new method for estimating the thinning rate and feeder EOL is developed using a probabilistic approach. The results of the study illustrate the benefits of the methodology in supporting risk-informed decision making at the station by quantifying the present and incremental risk in the feeder system over time. (author)

Risk-informed prediction of feeder end of life

Energy Technology Data Exchange (ETDEWEB)

Jyrkama, M.; Pandey, M. [Univ. of Waterloo, Ontario (Canada)

2011-07-01

The operating life of feeder piping is negatively impacted by flow accelerated corrosion (FAC). In this study, an assessment of a large set of inspection data reveals that FAC in feeders is a relatively stationary process, with variability only at the local scale. Given the added uncertainty from inspection coverage, a new method for estimating the thinning rate and feeder EOL is developed using a probabilistic approach. The results of the study illustrate the benefits of the methodology in supporting risk-informed decision making at the station by quantifying the present and incremental risk in the feeder system over time. (author)

Expectations of Cattle Feeding Investors in Feeder Cattle Placements

OpenAIRE

Kastens, Terry L.; Schroeder, Ted C.

1993-01-01

Cattle feeders appear irrational when they place cattle on feed when projected profits are negative. Long futures positions appear to offer superior returns to cattle feeding investment. Cattle feeder behavior suggests that they believe a downward bias in live cattle futures persists and that cattle feeders use different information than the live cattle futures market price when making placement decisions. This paper examines feeder cattle placement determinants and compares performance of ex...

A signature correlation study of ground target VHF/UHF ISAR imagery

Science.gov (United States)

Gatesman, Andrew J.; Beaudoin, Christopher J.; Giles, Robert H.; Kersey, William T.; Waldman, Jerry; Carter, Steve; Nixon, William E.

2003-09-01

VV and HH-polarized radar signatures of several ground targets were acquired in the VHF/UHF band (171-342 MHz) by using 1/35th scale models and an indoor radar range operating from 6 to 12 GHz. Data were processed into medianized radar cross sections as well as focused, ISAR imagery. Measurement validation was confirmed by comparing the radar cross section of a test object with a method of moments radar cross section prediction code. The signatures of several vehicles from three vehicle classes (tanks, trunks, and TELs) were measured and a signature cross-correlation study was performed. The VHF/UHF band is currently being exploited for its foliage penetration ability, however, the coarse image resolution which results from the relatively long radar wavelengths suggests a more challenging target recognition problem. One of the study's goals was to determine the amount of unique signature content in VHF/UHF ISAR imagery of military ground vehicles. Open-field signatures are compared with each other as well as with simplified shapes of similar size. Signatures were also acquired on one vehicle in a variety of configurations to determine the impact of monitor target variations on the signature content at these frequencies.

RTD application in low power UHF rectifiers

International Nuclear Information System (INIS)

Sinyakin, V Yu; Makeev, M O; Meshkov, S A

2016-01-01

In the current work, the problem of UHF RFID passive tag sensitivity increase is considered. Tag sensitivity depends on HF signal rectifier efficiency and antenna-rectifier impedance matching. Possibility of RFID passive tag sensitivity increase up to 10 times by means of RTD use in HF signal rectifier in comparison with tags based on Schottky barrier diode is shown. (paper)

Feeder density enhances house finch disease transmission in experimental epidemics.

Science.gov (United States)

Moyers, Sahnzi C; Adelman, James S; Farine, Damien R; Thomason, Courtney A; Hawley, Dana M

2018-05-05

Anthropogenic food provisioning of wildlife can alter the frequency of contacts among hosts and between hosts and environmental sources of pathogens. Despite the popularity of garden bird feeding, few studies have addressed how feeders influence host contact rates and disease dynamics. We experimentally manipulated feeder density in replicate aviaries containing captive, pathogen-naive, groups of house finches ( Haemorhous mexicanus ) and continuously tracked behaviours at feeders using radio-frequency identification devices. We then inoculated one bird per group with Mycoplasma gallisepticum (Mg), a common bacterial pathogen for which feeders are fomites of transmission, and assessed effects of feeder density on house finch behaviour and pathogen transmission. We found that pathogen transmission was significantly higher in groups with the highest density of bird feeders, despite a significantly lower rate of intraspecific aggressive interactions relative to the low feeder density groups. Conversely, among naive group members that never showed signs of disease, we saw significantly higher concentrations of Mg-specific antibodies in low feeder density groups, suggesting that birds in low feeder density treatments had exposure to subclinical doses of Mg. We discuss ways in which the density of garden bird feeders could play an important role in mediating the intensity of Mg epidemics.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'. © 2018 The Author(s).

Colour preferences of UK garden birds at supplementary seed feeders.

Directory of Open Access Journals (Sweden)

Luke Rothery

Full Text Available Supplementary feeding of garden birds generally has benefits for both bird populations and human wellbeing. Birds have excellent colour vision, and show preferences for food items of particular colours, but research into colour preferences associated with artificial feeders is limited to hummingbirds. Here, we investigated the colour preferences of common UK garden birds foraging at seed-dispensing artificial feeders containing identical food. We presented birds simultaneously with an array of eight differently coloured feeders, and recorded the number of visits made to each colour over 370 30-minute observation periods in the winter of 2014/15. In addition, we surveyed visitors to a garden centre and science festival to determine the colour preferences of likely purchasers of seed feeders. Our results suggest that silver and green feeders were visited by higher numbers of individuals of several common garden bird species, while red and yellow feeders received fewer visits. In contrast, people preferred red, yellow, blue and green feeders. We suggest that green feeders may be simultaneously marketable and attractive to foraging birds.

Special Semaphore Scheme for UHF Spacecraft Communications

Science.gov (United States)

Butman, Stanley; Satorius, Edgar; Ilott, Peter

2006-01-01

A semaphore scheme has been devised to satisfy a requirement to enable ultrahigh- frequency (UHF) radio communication between a spacecraft descending from orbit to a landing on Mars and a spacecraft, in orbit about Mars, that relays communications between Earth and the lander spacecraft. There are also two subsidiary requirements: (1) to use UHF transceivers, built and qualified for operation aboard the spacecraft that operate with residual-carrier binary phase-shift-keying (BPSK) modulation at a selectable data rate of 8, 32, 128, or 256 kb/s; and (2) to enable low-rate signaling even when received signals become so weak as to prevent communication at the minimum BPSK rate of 8 kHz. The scheme involves exploitation of Manchester encoding, which is used in conjunction with residual-carrier modulation to aid the carrier-tracking loop. By choosing various sequences of 1s, 0s, or 1s alternating with 0s to be fed to the residual-carrier modulator, one would cause the modulator to generate sidebands at a fundamental frequency of 4 or 8 kHz and harmonics thereof. These sidebands would constitute the desired semaphores. In reception, the semaphores would be detected by a software demodulator.

Round-bale feeder design affects hay waste and economics during horse feeding.

Science.gov (United States)

Martinson, K; Wilson, J; Cleary, K; Lazarus, W; Thomas, W; Hathaway, M

2012-03-01

Many horse owners find round bales convenient, less labor intensive, and more affordable than other hay types, but report an inability to control horse BW gain and excessive hay waste. The objectives were to compare hay waste, hay intake, and payback of 9 round-bale feeders and a no-feeder control when used during horse feeding. Nine round-bale feeders were tested: Cinch Net, Cone, Covered Cradle, Hayhut, Hay Sleigh, Ring, Tombstone, Tombstone Saver, and Waste Less. Each feeder design was placed on the ground in a dirt paddock. Five groups of 5 horses were fed in rotation for a 4-d period with each feeder. Every fourth day, groups were rotated among paddocks and a new round bale was placed in each feeder. In the 5 paddocks used, 5 feeders were installed for d 1 through 20, and the remaining 4 feeders and no-feeder control were installed for d 21 through 40. Groups of horses were sequentially assigned to feeders using two 5 × 5 Latin squares, the first for d 1 through 20, the second for d 21 through 40. Horse groups of similar age, BW, breed, and sex were formed from 25 Quarter Horse and Thoroughbred geldings and open mares (means: 11 yr; 541 kg of BW). Hay on the ground surrounding the feeder was collected daily, dried, and weighed. The total amount of hay removed around each feeder for a 4-d period was considered waste. Dry matter intake was estimated as the difference between hay disappearance and waste. Number of months for the reduction in waste to repay feeder cost (payback) were calculated using hay valued at $110/t, and improved feeder efficiency over the control. Feeder design did not affect hay intake (P > 0.05); all feeders resulted in an estimated hay intake of 2.0 to 2.4% BW; the no-feeder control resulted in a reduced intake of 1.3% BW (P = 0.001). Mean percentage of hay waste differed among feeders (P feeder control, 57%. Feeder design also affected payback (P feeder design affected hay waste and payback, but not estimated hay intake or BW change

Experimental Study on Inkjet-Printed Passive UHF RFID Tags on Versatile Paper-Based Substrates

Directory of Open Access Journals (Sweden)

Han He

2016-01-01

Full Text Available We present the possibilities and challenges of passive UHF RFID tag antennas manufactured by inkjet printing silver nanoparticle ink on versatile paper-based substrates. The most efficient manufacturing parameters, such as the pattern resolution, were determined and the optimal number of printed layers was evaluated for each substrate material. Next, inkjet-printed passive UHF RFID tags were fabricated on each substrate with the optimized parameters and number of layers. According to our measurements, the tags on different paper substrates showed peak read ranges of 4–6.5 meters and the tags on different cardboard substrates exhibited peak read ranges of 2–6 meters. Based on their wireless performance, these inkjet-printed paper-based passive UHF RFID tags are sufficient for many future wireless applications and comparable to tags fabricated on more traditional substrates, such as polyimide.

Impact of flow accelerated corrosion (FAC) on feeder refurbishment planning

International Nuclear Information System (INIS)

Jyrkama, M.; Pandey, M.

2010-01-01

Feeder wall thinning due to flow accelerated corrosion (FAC) may result in a large number of feeder replacements in the future. In this study, the process of FAC is modelled using a probabilistic approach and used to predict the expected number of degraded feeders and their replacements in the future. Because of the high cost associated with feeder replacements, it may be optimal to replace the entire feeder population during a single refurbishment outage when the unit cost of replacement is likely to be less. The results of this study demonstrate, however, that the unit cost of feeder replacement must be sufficiently lower than the standard replacement cost and the refurbishment performed at an optimal time to realize the economic benefits associated with the refurbishment. (author)

From VHF to UHF CMOS-MEMS Monolithically Integrated Resonators

DEFF Research Database (Denmark)

Teva, Jordi; Berini, Abadal Gabriel; Uranga, A.

2008-01-01

This paper presents the design, fabrication and characterization of microresonators exhibiting resonance frequencies in the VHF and UHF bands, fabricated using the available layers of the standard and commercial CMOS technology, AMS-0.35mum. The resonators are released in a post-CMOS process cons...

HF RFID versus UHF RFID--Technology for Library Service Transformation at City University of Hong Kong

Science.gov (United States)

Ching, Steve H.; Tai, Alice

2009-01-01

Since libraries first used RFID systems in the late 1990s, more and more libraries have identified the advantages of the technology. With advances in HF and UHF RFID, both alternatives are now viable in library applications. While some librarians are still skeptical towards UHF RFID as unproven in the library arena, the City University of Hong…

in meat production III. Feeder - breeder dimorphism

African Journals Online (AJOL)

Feeder- breeder dimorphism is advantageous when large offspring for slaughter is obtained from small breeding animals. The effect of feeder- breeder dimorphism on herd efficiency is evaluated for terminal crossbreeding and growth modification by biotechnological or dietary means. Selection criteria for breeds or lines in ...

Assessment of Multipath and Shadowing Effects on UHF Band in ...

African Journals Online (AJOL)

Sultan

bands are used for television broadcasting, mobile cellular systems, Wi-Fi, satellite communications and many others. Effective communication link in the UHF band requires direct line of sight ..... ad-hoc 802.11 wireless LAN (WLAN) devices.

A New Kind of Circular Polarization Leaky-Wave Antenna Based on Substrate Integrated Waveguide

Directory of Open Access Journals (Sweden)

Chong Zhang

2015-01-01

Full Text Available A new kind of circular polarization leaky-wave antenna with N-shaped slots cut in the upper side of substrate integrated waveguide (SIW is investigated and presented. The radiation pattern and polarization axial ratio of the leaky-wave antenna are studied. The results show that the width of N-shaped slots has significant effect on the circular polarization property of the antenna. By properly choosing structural parameters, the SIW based leaky-wave antenna can realize circular polarization with excellent axial ratio in 8 GHz satellite band.

Practical experience with the leaky-fuel monitoring at Bohunice NPP

International Nuclear Information System (INIS)

Kacmar, M.; Cizek, J.

2001-01-01

The first part of this paper describes practical experience with the fuel monitoring in operating reactors from point of view possible leakages. Summarized in the paper are numbers leaky fuel assemblies both for NPP and for particular units. Some failure causes are discussed for operational conditions of Bohunice NPP. In the second part of paper critical power ramps on hot fuel rod of leaky fuel assemblies are analysed to eliminate failures from PCI. The main aim of the paper is the need to understand the mechanism and causes of failures (Authors)

Determination of representative CANDU feeder dimensions for engineering simulator

International Nuclear Information System (INIS)

Cho, S.; Muzumdar, A.

1996-01-01

This paper describes a logic for selection of representative channel groups and a methodology for determination of representative CANDU feeder dimensions and the pressure drops between inlet/outlet header and fuel channel in the primary loop. A code, MEDOC, was developed based on this logic and methodology and helps perform a calculation of representative feeder dimensions for a selected channel group on the basis of feeder geometry data (fluid volume, mass flow rate, loss factor) and given property data (pressure, quality, density) at inlet/outlet header. The representative feeder dimensions calculated based on this methodology will be useful for the engineering simulator for the CANDU type reactor. (author)

Assessment of CANDU feeders subject to flow accelerated corrosion

Energy Technology Data Exchange (ETDEWEB)

Iyer, S. [Atomic Energy of Canada Ltd., Mississauga, Ontario (Canada); Slade, J.P. [New Brunswick Power, Point Lepreau Generating Station, Lepreau, New Brunswick (Canada)

2003-07-01

'Full Text:' Inspections of CANDU feeders have indicated greater than expected wall thinning of outlet feeders. This wall thinning is attributed to Flow-Accelerated Corrosion (FAC). The rate of wall loss due to FAC is highest in the close radius bends near the end fitting. The minimum allowed thickness for a feeder pipes is based on design pressure during the design stage. Extended operation of the thinned feeders beyond their design basis, i.e., operation of feeders with thickness below design pressure based minimum thickness has economic benefits for the utilities. In such cases, it is important to establish the remaining life and evaluate the adequacy of the components for safe operation. ASME Code Case N-597 provides the guidelines for acceptance for continued service of Classes 2 and 3 piping components experiencing wall thinning during operation. However, for Class 1 systems, the Code Case recommends that the owner develop the methodology and criteria for the assessment of wall thinning. Therefore, under the CANDU Owner's Group's (COG) Feeder Integrity Joint Program (FIJP), the 'Fitness for Service Guidelines (FFSG) for Feeders Affected by Wall Thinning in Operating CANDU Reactors' was developed and subsequently conditionally approved by CNSC. This paper illustrates the underlying concepts in the FFSG methodology and its benefits to utilities. Specific examples of the application and benefits of the FFSG at Point Lepreau G.S. are described in this paper. The assessment of feeders is based on the requirements of the construction Code (Section III of the ASME Boiler and Pressure Vessel Code): The following points briefly describe the assessment methodology. Satisfying the requirements of NB-3650 for design and service loadings are sufficient for continued service and extended life if the predicted minimum wall thickness of the component is greater than or equal to 90% of the pressure based thickness calculated as per NB-3641. The B

Feeding Against Gravity with Spot Feeders in High Silicon Ductile Iron

DEFF Research Database (Denmark)

Vedel-Smith, Nikolaj Kjelgaard; Tiedje, Niels Skat

2014-01-01

and classified using X-ray imaging and ultrasound analysis. The effect of the different feeder configurations were classified in reference to defect location, sleeve material, and feeder type, modulus, and location. The analysis showed that exothermal feeder sleeves with the right configurations can feed up......-hill against gravity. This effect may contribute to the thermal expansion created by the exothermal reaction. It was also found that the optimum feeder size does not scale linearly with the casting modulus but that larger casting modulus requires relatively smaller modulus feeders. The thermal gradient created...

26 CFR 1.502-1 - Feeder organizations.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Feeder organizations. 1.502-1 Section 1.502-1...) INCOME TAXES (CONTINUED) Exempt Organizations § 1.502-1 Feeder organizations. (a) In the case of an organization operated for the primary purpose of carrying on a trade or business for profit, exemption is not...

Novel Methods to Determine Feeder Locational PV Hosting Capacity and PV Impact Signatures

Energy Technology Data Exchange (ETDEWEB)

Reno, Matthew J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Coogan, Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Seuss, John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Broderick, Robert Joseph [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-05-01

Often PV hosting capacity analysis is performed for a limited number of distribution feeders. For medium - voltage distribution feeders, previous results generally analyze less than 20 feeders, and then the results are extrapolated out to similar types of feeders. Previous hosting capacity research has often focused on determining a single value for the hosting capacity for the entire feeder, whereas this research expands previous hosting capacity work to investigate all the regions of the feeder that may allow many different hosting capacity values wit h an idea called locational hosting capacity (LHC)to determine the largest PV size that can be interconnected at different locations (buses) on the study feeders. This report discusses novel methods for analyzing PV interconnections with advanced simulati on methods. The focus is feeder and location - specific impacts of PV that determine the locational PV hosting capacity. Feeder PV impact signature are used to more precisely determine the local maximum hosting capacity of individual areas of the feeder. T he feeder signature provides improved interconnection screening with certain zones that show the risk of impact to the distribution feeder from PV interconnections.

Coupled Particle Transport and Pattern Formation in a Nonlinear Leaky-Box Model

Science.gov (United States)

Barghouty, A. F.; El-Nemr, K. W.; Baird, J. K.

2009-01-01

Effects of particle-particle coupling on particle characteristics in nonlinear leaky-box type descriptions of the acceleration and transport of energetic particles in space plasmas are examined in the framework of a simple two-particle model based on the Fokker-Planck equation in momentum space. In this model, the two particles are assumed coupled via a common nonlinear source term. In analogy with a prototypical mathematical system of diffusion-driven instability, this work demonstrates that steady-state patterns with strong dependence on the magnetic turbulence but a rather weak one on the coupled particles attributes can emerge in solutions of a nonlinearly coupled leaky-box model. The insight gained from this simple model may be of wider use and significance to nonlinearly coupled leaky-box type descriptions in general.

Pressure vessels and methods of sealing leaky tubes disposed in pressure vessels

International Nuclear Information System (INIS)

Larson, G.C.

1980-01-01

This invention relates to pressure vessels and to methods of sealing leaky tubes in them and is especially applicable to pressure vessels in the form of sheet-and-tube type heat exchangers constructed with a large number of relatively small diameter tubes grouped in a bundle. To seal off a leaky tube in such a heat exchanger an explosive activated plug in the form of a hollow metal body is used, inserted at each end of the tube to be sealed. Using the arrangement of pressure vessel and associated tube sheets and the explosive activated plug method of sealing a leaky tube as described in this invention it is claimed that distortion of the adjacent tubes and the tube sheets is reduced when the explosive activated plugs are detonated. (U.K.)

Characterization of inkjet-printing HF and UHF antennas for RFID applications

Science.gov (United States)

Tarapata, Grzegorz; Paczesny, Daniel; Kawecki, Krzysztof

2013-10-01

The aim of this work was to perform a set of RFID antennas on flexible plastic substrates designed for range of HF and UHF band. The samples was fabricated using inkjet printing technology and conductive material base on silver nanopartilces ink. Fabricated antennas have been characterized, and the results were compared with the parameters of antennas made with usage of classical PCB technology on FR4 laminate with copper metallization. The paper presents studies on the impact of elastic substrates and conductive materials on antennas electrical parameters, as well as the communication range of the resulting RFID tags. During the experiment two patterns of HF and three patterns of UHF antennas was examined and the antennas was realized on different types of substrates, such as PET, Kapton® and FR4.

A Dynamic and Heuristic Phase Balancing Method for LV Feeders

Directory of Open Access Journals (Sweden)

Samad Taghipour Boroujeni

2016-01-01

Full Text Available Due to the single-phase loads and their stochastic behavior, the current in the distribution feeders is not balanced. In addition, the single-phase loads are located in different positions along the LV feeders. So the amount of the unbalanced load and its location affect the feeder losses. An unbalanced load causes the feeder losses and the voltage drop. Because of time-varying behavior of the single-phase loads, phase balancing is a dynamic and combinatorial problem. In this research, a heuristic and dynamic solution for the phase balancing of the LV feeders is proposed. In this method, it is supposed that the loads’ tie could be connected to all phases through a three-phase switch. The aim of the proposed method is to make the feeder conditions as balanced as possible. The amount and the location of single-phase loads are considered in the proposed phase balancing method. Since the proposed method needs no communication interface or no remote controller, it is inexpensive, simple, practical, and robust. Applying this method provides a distributed and dynamic phase balancing control. In addition, the feasibility of reducing the used switches is investigated. The ability of the proposed method in the phase balancing of the LV feeders is approved by carrying out some simulations.

The First Steps into a "Leaky Pipeline"

DEFF Research Database (Denmark)

Emerek, Ruth; Larsen, Britt Østergaard

2011-01-01

Research shows that the higher the level of academic positions at universities the lower the percentage of women among employees also applies at Danish universities. This may be due to a historical backlog or merely to a 'Leaky pipeline', as earlier studies have revealed that an increasing propor...

Structural integrity investigations of feeder pipe ice plugging procedures

International Nuclear Information System (INIS)

Flaman, M.T.; Shah, N.N.

1985-03-01

A procedure involving the use of a liquid nitrogen cooled heat exchanger to form internal ice plugs in feeder pipes is routinely used in nuclear generating stations. The use of this procedure has caused concerns with regard to the safety of station maintenance personnel, and in regard to the integrity of the feeder pipes. This report describes the results of laboratory stress and pressure measurements which were performed on a feeder pipe section during ice plugging operations to investigate these concerns. From the results of this study, and from the results of previous studies of material behaviour at low temperatures, it has been determined that the ice plugging procedure can be performed on feeder pipes in a safe and effective manner

Vertical-Screw-Auger Conveyer Feeder

Science.gov (United States)

Walton, Otis (Inventor); Vollmer, Hubert J. (Inventor)

2016-01-01

A conical feeder is attached to a vertically conveying screw auger. The feeder is equipped with scoops and rotated from the surface to force-feed regolith the auger. Additional scoops are possible by adding a cylindrical section above the conical funnel section. Such then allows the unit to collect material from swaths larger in diameter than the enclosing casing pipe of the screw auger. A third element includes a flexible screw auger. All three can be used in combination in microgravity and zero atmosphere environments to drill and recover a wide area of subsurface regolith and entrained volatiles through a single access point on the surface.

Study of the frequency modulation of various U.H.F. signals occurring in a linear electron accelerator; Etude de la modulation de frequence de divers signaux U.H.F. existant dans un accelerateur lineaire d'electrons

Energy Technology Data Exchange (ETDEWEB)

Bergere, R; Veyssiere, A; Daujat, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-06-01

This paper contains a digest of a series of studies on the frequency modulation of U.H.F. fields and signals associated with the linear electron accelerator at Saclay. We first consider the frequency modulation of a U. H. F. pulse before its injection into an accelerating structure and after its subsequent propagation when no accelerated electrons are present. We then apply a similar analysis to the frequency modulation due to the direct interaction of the electron beam itself, and the accelerating U.H.F. fields. Finally we consider the phase modulation of the elementary electron packet itself. This phase modulation can be correctly interpreted by considering the dynamics of the electron beam as such. This analysis moreover, gives a correct interpretation of the evolution of the phase modulation with time, as the elementary electron packets move along with the sinusoidal U.H.F. accelerating fields. (authors) [French] Cet article resume les etudes faites sur l'accelerateur lineaire d'electrons de Saclay a propos de la modulation de frequence des divers signaux U.H.F. presents autour de l'accelerateur. On etudie d'abord la modulation de frequence des impulsions U.H.F. entrant sur la structure acceleratrice ou transmises par cette structure en l'absence de faisceau d'electrons acceleres. On analyse ensuite la modulation de frequence resultant de l'interaction d'une de ces ondes avec le faisceau d'electrons acceleres. On etudie enfin, la modulation de phase des divers paquets elementaires constituant une impulsion d'electrons acceleres. On montre comment cette modulation de phase peut s'expliquer par des considerations sur la dynamique du faisceau et conduire a une representation dans les divers cas possibles de l'evolution de la phase d'accrochage des electrons sur l'onde sinusoidale progressive de champ accelerateur. (auteurs)

Assessment of multipath and shadowing effects on UHF band in ...

African Journals Online (AJOL)

In this work, the multi-path and shadowing effects on signal impairment were investigated through the use of empirical and semi-empirical path loss models analysis in built-up environments. Electromagnetic field strength measurements were conducted using four television transmitters at UHF bands along four major routes ...

Radial flow towards well in leaky unconfined aquifer

Science.gov (United States)

Mishra, P. K.; Kuhlman, K. L.

2012-12-01

An analytical solution is developed for three-dimensional flow towards a partially penetrating large- diameter well in an unconfined aquifer bounded below by a leaky aquitard of finite or semi-infinite extent. The analytical solution is derived using Laplace and Hankel transforms, then inverted numerically. Existing solutions for flow in leaky unconfined aquifers neglect the unsaturated zone following an assumption of instantaneous drainage due to Neuman. We extend the theory of leakage in unconfined aquifers by (1) including water flow and storage in the unsaturated zone above the water table, and (2) allowing the finite-diameter pumping well to partially penetrate the aquifer. The investigation of model-predicted results shows that aquitard leakage leads to significant departure from the unconfined solution without leakage. The investigation of dimensionless time-drawdown relationships shows that the aquitard drawdown also depends on unsaturated zone properties and the pumping-well wellbore storage effects.

Detection of moving humans in UHF wideband SAR

Science.gov (United States)

Sjögren, Thomas K.; Ulander, Lars M. H.; Frölind, Per-Olov; Gustavsson, Anders; Stenström, Gunnar; Jonsson, Tommy

2014-06-01

In this paper, experimental results for UHF wideband SAR imaging of humans on an open field and inside a forest is presented. The results show ability to detect the humans and suggest possible ways to improve the results. In the experiment, single channel wideband SAR mode of the UHF UWB system LORA developed by Swedish Defence Research Agency (FOI). The wideband SAR mode used in the experiment was from 220 to 450 MHz, thus with a fractional bandwidth of 0.68. Three humans walking and one stationary were available in the scene with one of the walking humans in the forest. The signature of the human in the forest appeared on the field, due to azimuth shift from the positive range speed component. One human on the field and the one in the forest had approximately the same speed and walking direction. The signatures in the SAR image were compared as a function of integration time based on focusing using the average relative speed of these given by GPS logs. A signal processing gain was obtained for the human in forest until approximately 15 s and 35 s for the human on the field. This difference is likely explained by uneven terrain and trees in the way, causing a non-straight walking path.

Damping considerations in CANDU feeder pipe design and analysis

International Nuclear Information System (INIS)

Usmani, S.A.; Saleem, M.A.; So, G.

1990-01-01

Recent developments in pipe damping indicate a trend towards more realistic and less conservative values, which result in less rigid and safer pipe designs. The CANDU-PHW (Canada deuterium uranium, pressurized heavy water) reactor feeder pipe designs have applied similar approaches which permit seismic qualifications without overly restraining these compact arrays of pipes to cater for the large creep and thermal anchor movement. This paper reviews the feeder design aspects, especially pertaining to the design provisions, experimental verification and analytical modelling for seismic qualification in the light of recent pipe dynamic developments. Using illustrative examples, comparison of seismic analysis results is provided for the ASME Code Case N-411 dampings, and those traditionally used in the feeder seismic qualification. The results confirm acceptability of the traditional approach which permit simplified analysis to demonstrate seismic qualificationqualification of CANDU feeder pipes

Automation Selection and Sequencing of Traps for Vibratory Feeders

DEFF Research Database (Denmark)

Mathiesen, Simon; Ellekilde, Lars-Peter

2017-01-01

Vibratory parts feeders with mechanical orienting devices are used extensively in the assembly automation industry. Even so, the design process is based on trial-and-error approaches and is largely manual. In this paper, a methodology is presented for automatic design of this type of feeder....... The approach uses dynamic simulation for generating the necessary data for configuring a feeder with a sequence of mechanical orienting devices called traps, with the goal of reorienting all parts from a random to fixed orientation. Then, a fast algorithm for facilitating this configuration task automatically...

Urban Bird Feeders Dominated by a Few Species and Individuals

Directory of Open Access Journals (Sweden)

Josie A. Galbraith

2017-08-01

Full Text Available The practice of garden bird feeding is a global phenomenon, involving millions of people and vast quantities of food annually. Many people engage in the practice of feeding assuming that birds gain some benefit from the food they provide, yet recent studies have revealed the potential for detrimental impacts as well. However, there is still a paucity of information on the impacts of feeding, including the ubiquity of these impacts among and within feeder-visiting species. Consistency in feeder use among birds is likely an important determinant of this. Individual birds and species that make frequent use of feeders are more likely to experience both the benefits and detrimental impacts of supplementary food. We investigated patterns of feeder use by garden birds visiting experimental feeding stations in Auckland, New Zealand, with the specific aim of determining whether use of supplementary food was consistent or variable among individuals and species. We used camera traps as well as Radio Frequency Identification (RFID technology to examine intra- and interspecific feeder visitation patterns and to discern species associations. Eleven bird species were detected using feeding stations, however, two introduced species (house sparrow Passer domesticus and spotted dove Streptopelia chinensis dominated visitation events. These species were present at feeders most frequently, with the largest conspecific group sizes. Significant associations were detected among a number of species, suggesting interspecific interactions are important in determining feeder use. We also found within-species differences in feeder use for all focal species, with individual variation greatest in house sparrows. Furthermore, season had an important influence on most visitation parameters. The observed individual and species-specific differences in supplementary food resource use imply that the impacts of garden bird feeding are not universal. Crucially, particularly given

Leaky vessels as a potential source of stromal acidification in tumours

KAUST Repository

Martin, Natasha K.

2010-12-01

Malignant tumours are characterised by higher rates of acid production and a lower extracellular pH than normal tissues. Previous mathematical modelling has indicated that the tumour-derived production of acid leads to a gradient of low pH in the interior of the tumour extending to a normal pH in the peritumoural tissue. This paper uses mathematical modelling to examine the potential of leaky vessels as an additional source of stromal acidification in tumours. We explore whether and to what extent increasing vascular permeability in vessels can lead to the breakdown of the acid gradient from the core of the tumour to the normal tissue, and a progressive acidification of the peritumoural stroma. We compare our mathematical simulations to experimental results found in vivo with a tumour implanted in the mammary fat pad of a mouse in a window chamber construct. We find that leaky vasculature can cause a net acidification of the normal tissue away from the tumour boundary, though not a progressive acidification over time as seen in the experiments. Only through progressively increasing the leakiness can the model qualitatively reproduce the experimental results. Furthermore, the extent of the acidification predicted by the mathematical model is less than as seen in the window chamber, indicating that although vessel leakiness might be acting as a source of acid, it is not the only factor contributing to this phenomenon. Nevertheless, tumour destruction of vasculature could result in enhanced stromal acidification and invasion, hence current therapies aimed at buffering tumour pH should also examine the possibility of preventing vessel disruption.

Neural stem cells achieve and maintain pluripotency without feeder cells.

Directory of Open Access Journals (Sweden)

Hyun Woo Choi

Full Text Available BACKGROUND: Differentiated cells can be reprogrammed into pluripotency by transduction of four defined transcription factors. Induced pluripotent stem cells (iPS cells are expected to be useful for regenerative medicine as well as basic research. Recently, the report showed that mouse embryonic fibroblasts (MEF cells are not essential for reprogramming. However, in using fibroblasts as donor cells for reprogramming, individual fibroblasts that had failed to reprogram could function as feeder cells. METHODOLOGY/PRINCIPAL FINDING: Here, we show that adult mouse neural stem cells (NSCs, which are not functional feeder cells, can be reprogrammed into iPS cells using defined four factors (Oct4, Sox2, Klf4, and c-Myc under feeder-free conditions. The iPS cells, generated from NSCs expressing the Oct4-GFP reporter gene, could proliferate for more than two months (passage 20. Generated and maintained without feeder cells, these iPS cells expressed pluripotency markers (Oct4 and Nanog, the promoter regions of Oct4 and Nanog were hypomethylated, could differentiated into to all three germ layers in vitro, and formed a germline chimera. These data indicate that NSCs can achieve and maintain pluripotency under feeder-free conditions. CONCLUSION/SIGNIFICANCE: This study suggested that factors secreted by feeder cells are not essential in the initial/early stages of reprogramming and for pluripotency maintenance. This technology might be useful for a human system, as a feeder-free reprogramming system may help generate iPS cells of a clinical grade for tissue or organ regeneration.

Advances in technologies for feeder pipe inspections

Energy Technology Data Exchange (ETDEWEB)

Ten Grotenhuis, R.; Verma, Y.; Hitchcox, T.; Sakuta, A. [Ontario Power Generation, Inspection and Maintenance Div., Toronto, Ontario (Canada)

2014-07-15

The successful development of the Matrix Inspection Technique (MIT) for feeder weld area applications has been followed up with a project to leverage the technology to address other aspects of feeder inspection. The goal of the project is to adapt the technology to provide full circumferential inspection of feeder pipes for FAC thinning and, potentially, for axial cracking. The project necessitated evolving a new generation of high speed, high element count data acquisition instruments. It also required the development of custom inspection arrays, innovative approaches to sealing the water column, use of inertial motion sensors to synthesize encoder inputs, real-time visual feedback for the operator, and enhanced automated analysis software capable of plotting the inspected configuration in 3D. The individual components of the system are currently being integrated into a whole. The results obtained to date demonstrate the approach to be fundamentally sound. (author)

A Decentralized Storage Strategy for Residential Feeders with Photovoltaics

DEFF Research Database (Denmark)

Marra, Francesco; Yang, Guangya; Træholt, Chresten

2014-01-01

. The power sizing of the ESSs is performed with linear programming (LP) method, based on voltage sensitivity analysis. A Belgian residential LV feeder with private PV systems is used as a case study to demonstrate the effectiveness of the proposed strategy. Quantification of the required energy levels...... domestic energy storage systems (ESS). The traditional way of operating a domestic ESS to increase the local consumption rate does not take into account the need of voltage support in a feeder; the proposed storage concept improves the traditional one, by mitigating voltage rise due to PV in the feeder...

A Compact RFID Reader Antenna for UHF Near-Field and Far-Field Operations

Directory of Open Access Journals (Sweden)

Lai Xiao zheng

2013-01-01

Full Text Available A compact loop antenna is presented for mobile ultrahigh frequency (UHF radio frequency identification (RFID application. This antenna, printed on a 0.8 mm thick FR4 substrate with a small size of 31 mm × 31 mm, achieves good impedance bandwidth from 897 to 928 MHz, which covers USA RFID Band (902–928 MHz. The proposed loop configuration, with a split-ring resonator (SRR coupled inside it, demonstrates strong and uniform magnetic field distribution in the near-field antenna region. Its linearly polarized radiation pattern provides available far-field gain. Finally, the reading capabilities of antenna are up to 56 mm for near-field and 1.05 m for far-field UHF RFID operations, respectively.

Effects of Rubber Loading on the Ultrasonic Backward Radiation Profile of Leaky Lamb Wave

International Nuclear Information System (INIS)

Song, Sung Jin; Jung, Min Ho; Kim, Young H.; Kwon, Sung Duk

2002-01-01

The characterization of adhesive property in multi-layer materials has been hot issue for a long time. In order to evaluate adhesive properties, we constructed fully automated system for the backward radiation of leaky Lamb wave. The backward radiation profiles were obtained for the bare steel plate and plates with rubber-loading. The rf waveforms and frequency spectra of backward radiation show the characteristics of involved leaky Lamb wave modes. As the thickness of rubber-loading increased, the amplitude of profile at the incident angle of 13.4' exponentially decreased. Scanning the incident position over the partially rubber-loaded specimen shows good agreement with the actual rubber-loading. The backward radiation of leaky Lamb wave has great potential to evaluate the adhesive condition as well as material properties of plates

Effects of Feeder Cells on Dopaminergic Differentiation of Human Embryonic Stem Cells

Directory of Open Access Journals (Sweden)

Zhenqiang Zhao

2016-12-01

Full Text Available Mouse embryonic fibroblasts (MEFs and human foreskin fibroblasts (HFFs are used for the culture of human embryonic stem cells (hESCs. MEFs and HFFs differed in their capacity to support the proliferation and pluripotency of hESCs and could affect cardiac differentiation potential of hESCs. The aim of this study was to evaluate the effect of MEFs and HFFs feeders on dopaminergic differentiation of hESCs lines. To minimize the impact of culture condition variation, two hESCs lines were cultured on mixed feeder cells (MFCs, MEFs: HFFs =1:1 and HFFs feeder respectively, and then were differentiated into DA neurons under the identical protocol. Dopaminergic differentiation was evaluated by immunocytochemistry, quantitative fluorescent real-time PCR (qRT-PCR, transmission and scanning electron microscopy, and patch clamp. Our results demonstrated that these hESCs-derived neurons were genuine and functional DA neurons. However, compared to hESCs line on MFCs feeder, hESCs line on HFFs feeder had a higher proportion of TH positive cells and expressed higher levels of FOXA2, PITX3, NURR1 and TH genes. In addition, the values of threshold intensity and threshold membrane potential of DA neurons from hESCs line on HFFs feeder were lower than those of DA neurons from hESCs line on the MFCs feeder. In conclusion, HFFs feeder not only facilitated the differentiation of hESCs cells into dopaminergic neurons, but also induced hESCs-derived DA neurons to express higher electrophysiological excitability. Therefore, feeder cells could affect not only dopaminergic differentiation potential of different hESCs lines, but also electrophysiological properties of hESCs-derived DA neurons.

Object categorization by wild ranging birds-Winter feeder experiments.

Science.gov (United States)

Nováková, Nela; Veselý, Petr; Fuchs, Roman

2017-10-01

The object categorization is only scarcely studied using untrained wild ranging animals and relevant stimuli. We tested the importance of the spatial position of features salient for categorization of a predator using wild ranging birds (titmice) visiting a winter feeder. As a relevant stimulus we used a dummy of a raptor, the European sparrowhawk (Accipiter nisus), placed at the feeding location. This dummy was designed to be dismantled into three parts and rearranged with the head in the correct position, in the middle or at the bottom of the dummy. When the birds had the option of visiting an alternative feeder with a dummy pigeon, they preferred this option to visiting the feeder with the dummy sparrowhawk with the head in any of the three positions. When the birds had the option of visiting an alternative feeder with an un-rearranged dummy sparrowhawk, they visited both feeders equally often, and very scarcely. This suggests that the titmice considered all of the sparrowhawk modifications as being dangerous, and equally dangerous as the un-rearranged sparrowhawk. The position of the head was not the most important cue for categorization. The presence of the key features was probably sufficient for categorization, and their mutual spatial position was of lower importance. Copyright © 2017 Elsevier B.V. All rights reserved.

Stress analysis of feeder bends using neutrons: new results and cumulative impacts

Energy Technology Data Exchange (ETDEWEB)

Banks, D.; Donaberger, R. [Canadian Neutron Beam Centre, Chalk River, ON (Canada); Leitch, B. [Atomic Energy of Canada Limited, Chalk River, ON (Canada); Rogge, R.B. [Canadian Neutron Beam Centre, Chalk River, ON (Canada)

2014-07-01

Neutron diffraction has played a vital role in stress analysis of bends in carbon steel pipes, known as feeder pipes, in CANDU reactors. Due to incidents of cracking of feeders, extensive R&D programs to manage feeder cracking have been implemented over about ten years. We review the cumulative impacts of this research from the view point of the stress analysis using neutrons, and present new results by examining a feeder bend with a partial crack both experimentally using neutron diffraction and theoretically using a finite element model. (author)

Disturbances in VHF/UHF telemetry links as a possible effect of the 2003 Hokkaido Tokachi-oki earthquake

Directory of Open Access Journals (Sweden)

H. Nagamoto

2008-08-01

Full Text Available The data on radio telemetry links (for water information at VHF/UHF in Hokkaido are used to investigate the rate of disturbances on radio links (or connection failure and its association with a huge earthquake, Tokachi-oki earthquake on 26 September 2003. Especially, the telemetry links at the Tokachi region closest to the earthquake epicenter, showed a significant increase in disturbances on radio links two weeks to a few days before the earthquake on the basis of analysis during a long interval from 1 June 2002 to 3 November 2007 (over 5 years. We suggest that these severe disturbances in VHF/UHF telemetry links are attributed to the generation of seismogenic VHF/UHF radio noises (emissions. Based on this idea, we have estimated that the intensity of these seismogenic emissions is on the order of 10–19 dB μV/m. Finally, the present result was compared with other physical parameters already obtained for this earthquake.

Impacting effects of seismic loading in feeder pipes of PHWR power plants

International Nuclear Information System (INIS)

Kumar, R.

1996-01-01

The core of a pressurized heavy water reactor (PHWR) consists of a large number of fuel channels. These fuel channels are connected to the feeder pipes through which the heavy water flows and transports heat from the reactor core to the steam generators. The feeder pipes are several hundreds in number. They run close to each other with small gaps and have several bends. Thus they represent a complex piping system. Under seismic loading, the adjacent feeder pipes may impact each other. In this paper a simplified procedure has been established to assess such impacting effects. The results of the proposed analysis include bending moment and impact force, which provide the stresses due to impacting effects. These results are plotted in nondimensional form so that they could be utilized for any set of feeder pipes. The procedure used for studying the impacting effects includes seismic analysis of individual feeder pipes without impacting effects, selection of pipes for impact analysis, and estimating their maximum impact velocity. Based on the static and dynamic characteristics of the selected feeder pipes, the maximum bending moment, impact force, and stresses are obtained. The results of this study are useful for quick evaluation of the impacting effects in feeder pipes

Saturated-unsaturated flow in a compressible leaky-unconfined aquifer

Science.gov (United States)

Mishra, Phoolendra K.; Vesselinov, Velimir V.; Kuhlman, Kristopher L.

2012-06-01

An analytical solution is developed for three-dimensional flow towards a partially penetrating large-diameter well in an unconfined aquifer bounded below by a leaky aquitard of finite or semi-infinite extent. The analytical solution is derived using Laplace and Hankel transforms, then inverted numerically. Existing solutions for flow in leaky unconfined aquifers neglect the unsaturated zone following an assumption of instantaneous drainage due to Neuman. We extend the theory of leakage in unconfined aquifers by (1) including water flow and storage in the unsaturated zone above the water table, and (2) allowing the finite-diameter pumping well to partially penetrate the aquifer. The investigation of model-predicted results shows that aquitard leakage leads to significant departure from the unconfined solution without leakage. The investigation of dimensionless time-drawdown relationships shows that the aquitard drawdown also depends on unsaturated zone properties and the pumping-well wellbore storage effects.

S08: investigation and repair of a cracked feeder at Point Lepreau GS

International Nuclear Information System (INIS)

A Celovsky, A.; Wright, M.D.; Gendron, T.S.

1997-01-01

Early in 1997 investigation of a low level leak in the Point Lepreau GS (PLGS) PHTS revealed that an outlet feeder, S08, was leaking. Ultrasonic inspection, and subsequent failure analysis, revealed that the leak was a consequence of a crack. Given the unusual nature of this event, and current concerns over feeder thinning, a detailed and careful removal and examination procedure was developed. The S08 outlet feeder was removed and shipped to Chalk River Laboratories for examination. The examination confirmed that the failure was a through-wall crack, most likely the consequence of stress corrosion cracking. A critical point of the analysis was to determine how the crack initiated, and subsequently propagated. High residual stresses and possible abnormal loading in conjunction with chemistry environments resulted in the Stress Corrosion Cracking (SCC) of the S08 outlet feeder bend. It is recognized that some of the causative factors implicated in the S08 failure apply to other outlet feeders. In particular, residual stresses in the non-stress-relieved, short-radius cold bent pipes will remain relatively high over the future life of the feeders. However, the risk of CANDU feeder failure by SCC is judged to be extremely low based on the evidence of the inspections carried out to date and the good performance record of feeder pipe in the CANDU industry. The channel was restored to its locked configuration, and the failed section of feeder replaced. (author)

Calibration of ultra-high frequency (UHF) partial discharge sensors using FDTD method

Science.gov (United States)

Ishak, Asnor Mazuan; Ishak, Mohd Taufiq

2018-02-01

Ultra-high frequency (UHF) partial discharge sensors are widely used for conditioning monitoring and defect location in insulation system of high voltage equipment. Designing sensors for specific applications often requires an iterative process of manufacturing, testing and mechanical modifications. This paper demonstrates the use of finite-difference time-domain (FDTD) technique as a tool to predict the frequency response of UHF PD sensors. Using this approach, the design process can be simplified and parametric studies can be conducted in order to assess the influence of component dimensions and material properties on the sensor response. The modelling approach is validated using gigahertz transverse electromagnetic (GTEM) calibration system. The use of a transient excitation source is particularly suitable for modeling using FDTD, which is able to simulate the step response output voltage of the sensor from which the frequency response is obtained using the same post-processing applied to the physical measurement.

Transient well flow in leaky multiple-aquifer systems

Science.gov (United States)

Hemker, C. J.

1985-10-01

A previously developed eigenvalue analysis approach to groundwater flow in leaky multiple aquifers is used to derive exact solutions for transient well flow problems in leaky and confined systems comprising any number of aquifers. Equations are presented for the drawdown distribution in systems of infinite extent, caused by wells penetrating one or more of the aquifers completely and discharging each layer at a constant rate. Since the solution obtained may be regarded as a combined analytical-numerical technique, a type of one-dimensional modelling can be applied to find approximate solutions for several complicating conditions. Numerical evaluations are presented as time-drawdown curves and include effects of storage in the aquitard, unconfined conditions, partially penetrating wells and stratified aquifers. The outcome of calculations for relatively simple systems compares very well with published corresponding results. The proposed multilayer solution can be a valuable tool in aquifer test evaluation, as it provides the analytical expression required to enable the application of existing computer methods to the determination of aquifer characteristics.

Fixing the Leaky Pipeline | Women in Science | Initiatives | Indian ...

Indian Academy of Sciences (India)

Home; Initiatives; Women in Science; Fixing the Leaky Pipeline ... Why aren't there many women in the top spots in academia? .... of women scientists, at a young age of 52, after a valiant battle with cancer, today on 29th March 2016 in Delhi.

Acoustically Driven Fluid and Particle Motion in Confined and Leaky Systems

Science.gov (United States)

Barnkob, Rune; Nama, Nitesh; Ren, Liqiang; Huang, Tony Jun; Costanzo, Francesco; Kähler, Christian J.

2018-01-01

The acoustic motion of fluids and particles in confined and acoustically leaky systems is receiving increasing attention for its use in medicine and biotechnology. A number of contradicting physical and numerical models currently exist, but their validity is uncertain due to the unavailability of hard-to-access experimental data for validation. We provide experimental benchmarking data by measuring 3D particle trajectories and demonstrate that the particle trajectories can be described numerically without any fitting parameter by a reduced-fluid model with leaky impedance-wall conditions. The results reveal the hitherto unknown existence of a pseudo-standing wave that drives the acoustic streaming as well as the acoustic radiation force on suspended particles.

Dry piston coal feeder

Science.gov (United States)

Hathaway, Thomas J.; Bell, Jr., Harold S.

1979-01-01

This invention provides a solids feeder for feeding dry coal to a pressurized gasifier at elevated temperatures substantially without losing gas from the gasifier by providing a lock having a double-acting piston that feeds the coals into the gasifier, traps the gas from escaping, and expels the trapped gas back into the gasifier.

A generalized leaky FxLMS algorithm for tuning the waterbed effect of feedback active noise control systems

Science.gov (United States)

Wu, Lifu; Qiu, Xiaojun; Guo, Yecai

2018-06-01

To tune the noise amplification in the feedback system caused by the waterbed effect effectively, an adaptive algorithm is proposed in this paper by replacing the scalar leaky factor of the leaky FxLMS algorithm with a real symmetric Toeplitz matrix. The elements in the matrix are calculated explicitly according to the noise amplification constraints, which are defined based on a simple but efficient method. Simulations in an ANC headphone application demonstrate that the proposed algorithm can adjust the frequency band of noise amplification more effectively than the FxLMS algorithm and the leaky FxLMS algorithm.

Improvement of automatic fish feeder machine design

Science.gov (United States)

Chui Wei, How; Salleh, S. M.; Ezree, Abdullah Mohd; Zaman, I.; Hatta, M. H.; Zain, B. A. Md; Mahzan, S.; Rahman, M. N. A.; Mahmud, W. A. W.

2017-10-01

Nation Plan of action for management of fishing is target to achieve an efficient, equitable and transparent management of fishing capacity in marine capture fisheries by 2018. However, several factors influence the fishery production and efficiency of marine system such as automatic fish feeder machine could be taken in consideration. Two latest fish feeder machines have been chosen as the reference for this study. Based on the observation, it has found that the both machine was made with heavy structure, low water and temperature resistance materials. This research’s objective is to develop the automatic feeder machine to increase the efficiency of fish feeding. The experiment has conducted to testing the new design of machine. The new machine with maximum storage of 5 kg and functioning with two DC motors. This machine able to distribute 500 grams of pellets within 90 seconds and longest distance of 4.7 meter. The higher speed could reduce time needed and increase the distance as well. The minimum speed range for both motor is 110 and 120 with same full speed range of 255.

Pressurized feeder for biofuels; Paineistettu syoetin biopolttoaineille

Energy Technology Data Exchange (ETDEWEB)

Lundqvist, R.; Makkonen, P. [Foster Wheeler Energia Oy, Karhula (Finland). Karhula R and D Center

1995-12-31

A new type of pressurized piston feeder has been tested for further development of the IGCC concept. The project is funded by the Finnish Ministry of Trade and Industry. The objective has been to develop a substitute for lock-hopper systems, which are commercial, but far too expensive from an operational point of view, due to high inert gas consumption for pressurization. The new feeder system, which is of dual piston type, uses little inert gas, because the pressurization sequence is performed partially by the piston movement. The project comprised further development of the concept, mechanical testing under atmospheric and pressurized conditions and testing with wood chips, peat and coal at elevated pressures. The main concern has been the wear of seals and gaskets during long term operation and for this reason over 600 hours of testing has been carried out. The tests were carried out between May 1994 and January 1995 with wood chips, peat and coal mainly at 17 bar(a) pressure. During the operation, the system was fine-tuned, and generally, the testing was successful. At the early stage of the tests, the ring seal design was modified and several alternative seal constructions were tested. During the tests, the seal was developed further and improved. The present ring seal design has been proven reliable and it meets the commercial requirements. After the tests, the feeder system was inspected thoroughly and found to be in good condition. A commercially available concept of the feeder has been developed on the basis of the knowledge obtained during the test runs

Pressurized feeder for biofuels; Paineistettu syoetin biopolttoaineille

Energy Technology Data Exchange (ETDEWEB)

Lundqvist, R; Makkonen, P [Foster Wheeler Energia Oy, Karhula (Finland). Karhula R and D Center

1996-12-31

A new type of pressurized piston feeder has been tested for further development of the IGCC concept. The project is funded by the Finnish Ministry of Trade and Industry. The objective has been to develop a substitute for lock-hopper systems, which are commercial, but far too expensive from an operational point of view, due to high inert gas consumption for pressurization. The new feeder system, which is of dual piston type, uses little inert gas, because the pressurization sequence is performed partially by the piston movement. The project comprised further development of the concept, mechanical testing under atmospheric and pressurized conditions and testing with wood chips, peat and coal at elevated pressures. The main concern has been the wear of seals and gaskets during long term operation and for this reason over 600 hours of testing has been carried out. The tests were carried out between May 1994 and January 1995 with wood chips, peat and coal mainly at 17 bar(a) pressure. During the operation, the system was fine-tuned, and generally, the testing was successful. At the early stage of the tests, the ring seal design was modified and several alternative seal constructions were tested. During the tests, the seal was developed further and improved. The present ring seal design has been proven reliable and it meets the commercial requirements. After the tests, the feeder system was inspected thoroughly and found to be in good condition. A commercially available concept of the feeder has been developed on the basis of the knowledge obtained during the test runs

A Novel Computational Method to Reduce Leaky Reaction in DNA Strand Displacement

Directory of Open Access Journals (Sweden)

Xin Li

2015-01-01

Full Text Available DNA strand displacement technique is widely used in DNA programming, DNA biosensors, and gene analysis. In DNA strand displacement, leaky reactions can cause DNA signals decay and detecting DNA signals fails. The mostly used method to avoid leakage is cleaning up after upstream leaky reactions, and it remains a challenge to develop reliable DNA strand displacement technique with low leakage. In this work, we address the challenge by experimentally evaluating the basic factors, including reaction time, ratio of reactants, and ion concentration to the leakage in DNA strand displacement. Specifically, fluorescent probes and a hairpin structure reporting DNA strand are designed to detect the output of DNA strand displacement, and thus can evaluate the leakage of DNA strand displacement reactions with different reaction time, ratios of reactants, and ion concentrations. From the obtained data, mathematical models for evaluating leakage are achieved by curve derivation. As a result, it is obtained that long time incubation, high concentration of fuel strand, and inappropriate amount of ion concentration can weaken leaky reactions. This contributes to a method to set proper reaction conditions to reduce leakage in DNA strand displacement.

A Feeder-Bus Dispatch Planning Model for Emergency Evacuation in Urban Rail Transit Corridors

Science.gov (United States)

Wang, Yun; Yan, Xuedong; Zhou, Yu; Zhang, Wenyi

2016-01-01

The mobility of modern metropolises strongly relies on urban rail transit (URT) systems, and such a heavy dependence causes that even minor service interruptions would make the URT systems unsustainable. This study aims at optimally dispatching the ground feeder-bus to coordinate with the urban rails’ operation for eliminating the effect of unexpected service interruptions in URT corridors. A feeder-bus dispatch planning model was proposed for the collaborative optimization of URT and feeder-bus cooperation under emergency situations and minimizing the total evacuation cost of the feeder-buses. To solve the model, a concept of dummy feeder-bus system is proposed to transform the non-linear model into traditional linear programming (ILP) model, i.e., traditional transportation problem. The case study of Line #2 of Nanjing URT in China was adopted to illustrate the model application and sensitivity analyses of the key variables. The modeling results show that as the evacuation time window increases, the total evacuation cost as well as the number of dispatched feeder-buses decrease, and the dispatched feeder-buses need operate for more times along the feeder-bus line. The number of dispatched feeder-buses does not show an obvious change with the increase of parking spot capacity and time window, indicating that simply increasing the parking spot capacity would cause huge waste for the emergent bus utilization. When the unbalanced evacuation demand exists between stations, the more feeder-buses are needed. The method of this study will contribute to improving transportation emergency management and resource allocation for URT systems. PMID:27676179

Isotope effects accompanying evaporation of water from leaky containers.

Science.gov (United States)

Rozanski, Kazimierz; Chmura, Lukasz

2008-03-01

Laboratory experiments aimed at quantifying isotope effects associated with partial evaporation of water from leaky containers have been performed under three different settings: (i) evaporation into dry atmosphere, performed in a dynamic mode, (ii) evaporation into dry atmosphere, performed in a static mode, and (iii) evaporation into free laboratory atmosphere. The results demonstrate that evaporative enrichment of water stored in leaky containers can be properly described in the framework of the Craig-Gordon evaporation model. The key parameter controlling the degree of isotope enrichment is the remaining fraction of water in the leaking containers. Other factors such as temperature, relative humidity, or extent of kinetic fractionation play only minor roles. Satisfactory agreement between observed and predicted isotope enrichments for both (18)O and (2)H in experiments for the case of evaporation into dry atmosphere could be obtained only when molecular diffusivity ratios of isotope water molecules as suggested recently by Cappa et al. [J. Geophys. Res., 108, 4525-4535, (2003).] were adopted. However, the observed and modelled isotope enrichments for (2)H and (18)O could be reconciled also for the ratios of molecular diffusivities obtained by Merlivat [J. Chem. Phys., 69, 2864-2871 (1978).], if non-negligible transport resistance in the viscous liquid sub-layer adjacent to the evaporating surface is considered. The evaporation experiments revealed that the loss of mass of water stored in leaky containers in the order of 1%, will lead to an increase of the heavy isotope content in this water by ca. 0.35 and 1.1 per thousand, for delta (18)O and delta (2)H, respectively.

Asymptotic spectral analysis in colliding leaky quantum layers

Czech Academy of Sciences Publication Activity Database

Kondej, S.; Krejčiřík, David

2017-01-01

Roč. 446, č. 2 (2017), s. 1328-1355 ISSN 0022-247X R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : quantum layers * leaky graphs * Delta interaction supported on hypersurfaces * Norm-resolvent convergence * non-self-adjoint interaction Subject RIV: BE - Theoretical Physics OBOR OECD: Applied mathematics Impact factor: 1.064, year: 2016

Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint

Energy Technology Data Exchange (ETDEWEB)

Nagarajan, Adarsh; Nelson, Austin; Prabakar, Kumaraguru; Hoke, Andy; Asano, Marc; Ueda, Reid; Nepal, Shaili

2017-06-15

As advanced grid-support functions (AGF) become more widely used in grid-connected photovoltaic (PV) inverters, utilities are increasingly interested in their impacts when implemented in the field. These effects can be understood by modeling feeders in real-time systems and testing PV inverters using power hardware-in-the-loop (PHIL) techniques. This paper presents a novel feeder model reduction algorithm using a Monte Carlo method that enables large feeders to be solved and operated on real-time computing platforms. Two Hawaiian Electric feeder models in Synergi Electric's load flow software were converted to reduced order models in OpenDSS, and subsequently implemented in the OPAL-RT real-time digital testing platform. Smart PV inverters were added to the real-time model with AGF responses modeled after characterizing commercially available hardware inverters. Finally, hardware inverters were tested in conjunction with the real-time model using PHIL techniques so that the effects of AGFs on the choice feeders could be analyzed.

Gap asymptotics in a weakly bent leaky quantum wire

Czech Academy of Sciences Publication Activity Database

Exner, Pavel; Kondej, S.

2015-01-01

Roč. 48, č. 49 (2015), s. 495301 ISSN 1751-8113 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : singular Schroedinger operators * delta interaction * leaky quantum wires * weak perturbation * asymptotic expansion Subject RIV: BE - Theoretical Physics Impact factor: 1.933, year: 2015

Final report on the evolution of supporting conditions for the feeders of 500 MWe PHWR

International Nuclear Information System (INIS)

Mishra, Rajesh; Soni, R.S.; Kushawaha, H.S.; Mahajan, S.C.; Kakodkar, A.; Hariprasad, K.

1994-01-01

This report deals with the evolution of generic supporting conditions for the feeders of 500 MWe PHWR based on the analysis and qualification of a few representative feeders. There are 196 different feeder pipe configurations for a total of 748 feeders. The present analysis was aimed at evolving a generalised supporting criteria based on the analysis of some representative feeders. The analysis was carried out for various loadings viz. pressure, temperature, dead weight, operating basis earthquake (OBE), safe shutdown earthquake (SSE) and creep loadings. The analysis for OBE and SSE loadings were carried out using response spectrum method. The effect of spacers between various feeders was modelled using higher damping values than those prescribed in ASME code. Based on the above analyses, generic supporting arrangements for the feeders of various groups have been finalized. This report gives details about the mathematical modelling, the analysis approach, the optimised supporting criteria, finalization of grouping and fixing of boundaries between various groups of feeders. (author). 34 refs., 51 figs., 69 tabs

Numerical simulation of the leaky dielectric microdroplet generation in electric fields

Science.gov (United States)

Kamali, Reza; Manshadi, Mohammad Karim Dehghan

2016-07-01

Microdroplet generation has a vast range of applications in the chemical, biomedical, and biological sciences. Several devices are applied to produce microdroplets, such as Co-flow, T-junction and Flow-focusing. The important point in the producing process is controlling the separated fluid volume in these devices. On the other hand, a large number of liquids, especially aqueous one, are influenced by electric or magnetic fields. As a consequence, an electric field could be used in order to affect the separated fluid volume. In this study, effects of an electric field on the microdroplet generation in a Co-flow device are investigated numerically. Furthermore, effects of some electrical properties such as permittivity on the separating process of microdroplets are studied. Leaky dielectric and perfect dielectric models are used in this investigation. According to the results, in the microdroplet generating process, leaky dielectric fluids show different behaviors, when an electric field is applied to the device. In other words, in a constant electric field strength, the volume of generated microdroplets can increase or decrease, in comparison with the condition without the electric field. However, for perfect dielectric fluids, droplet volume always decreases with increasing the electric field strength. In order to validate the numerical method of this study, deformation of a leaky dielectric droplet in an electric field is investigated. Results are compared with Taylor theoretical model.

Laser Generated Leaky Acoustic Waves for Needle Visualization.

Science.gov (United States)

Wu, Kai-Wen; Wang, Yi-An; Li, Pai-Chi

2018-04-01

Ultrasound (US)-guided needle operation is usually used to visualize both tissue and needle position such as tissue biopsy and localized drug delivery. However, the transducer-needle orientation is limited due to reflection of the acoustic waves. We proposed a leaky acoustic wave method to visualize the needle position and orientation. Laser pulses are emitted on top of the needle to generate acoustic waves; then, these acoustic waves propagate along the needle surface. Leaky wave signals are detected by the US array transducer. The needle position can be calculated by phase velocities of two different wave modes and their corresponding emission angles. In our experiments, a series of needles was inserted into a tissue mimicking phantom and porcine tissue to evaluate the accuracy of the proposed method. The results show that the detection depth is up to 51 mm and the insertion angle is up to 40° with needles of different diameters. It is demonstrated that the proposed approach outperforms the conventional B-mode US-guided needle operation in terms of the detection range while achieving similar accuracy. The proposed method reveals the potentials for further clinical applications.

RFID antenna design for circular polarization in UHF band

Science.gov (United States)

Shahid, Hamza; Khan, Muhammad Talal Ali; Tayyab, Umais; Irshad, Usama Bin; Alkhazraji, Emad; Javaid, Muhammad Sharjeel

2017-05-01

A miniature half cross dipole antenna for defense and aerospace RFID applications in UHF band is presented. The dipole printed line arms are half crossed shape on top of dielectric substrate backed by reactive impedance surface. The antenna fed by a coaxial cable at the gap separating the dipole arms. Our design is intended to work at 2.42 GHz for RFID readers. The radiation pattern obtained has HPBW of 112, return loss of 22.24 dB and 90 MHz bandwidth.

Real-Time Characterization of Materials Degradation Using Leaky Lamb Wave

Science.gov (United States)

Shiuh, S.; Bar-Cohen, Y.

1997-01-01

Leaky Lamb wave (LLW) propagation in composite materials has been studied extensively since it was first observed in 1982. The wave is induced using a pitch-catch arrangement and the plate wave modes are detected by searching minima in the reflected spectra.

Bundle-sheath leakiness in C4 photosynthesis: a careful balancing act between CO2 concentration and assimilation.

Science.gov (United States)

Kromdijk, Johannes; Ubierna, Nerea; Cousins, Asaph B; Griffiths, Howard

2014-07-01

Crop species with the C4 photosynthetic pathway are generally characterized by high productivity, especially in environmental conditions favouring photorespiration. In comparison with the ancestral C3 pathway, the biochemical and anatomical modifications of the C4 pathway allow spatial separation of primary carbon acquisition in mesophyll cells and subsequent assimilation in bundle-sheath cells. The CO2-concentrating C4 cycle has to operate in close coordination with CO2 reduction via the Calvin-Benson-Bassham (CBB) cycle in order to keep the C4 pathway energetically efficient. The gradient in CO2 concentration between bundle-sheath and mesophyll cells facilitates diffusive leakage of CO2. This rate of bundle-sheath CO2 leakage relative to the rate of phosphoenolpyruvate carboxylation (termed leakiness) has been used to probe the balance between C4 carbon acquisition and subsequent reduction as a result of environmental perturbations. When doing so, the correct choice of equations to derive leakiness from stable carbon isotope discrimination (Δ(13)C) during gas exchange is critical to avoid biased results. Leakiness responses to photon flux density, either short-term (during measurements) or long-term (during growth and development), can have important implications for C4 performance in understorey light conditions. However, recent reports show leakiness to be subject to considerable acclimation. Additionally, the recent discovery of two decarboxylating C4 cycles operating in parallel in Zea mays suggests that flexibility in the transported C4 acid and associated decarboxylase could also aid in maintaining C4/CBB balance in a changing environment. In this paper, we review improvements in methodology to estimate leakiness, synthesize reports on bundle-sheath leakiness, discuss different interpretations, and highlight areas where future research is necessary. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology

limit loads for wall-thinning feeder pipes under combined bending and internal pressure

International Nuclear Information System (INIS)

Je, Jin Ho; Lee, Kuk Hee; Chung, Ha Joo; Kim, Ju Hee; Han, Jae Jun; Kim, Yun Jae

2009-01-01

Flow Accelerated Corrosion (FAC) during inservice conditions produces local wall-thinning in the feeder pipes of CANDU. The Wall-thinning in the feeder pipes is main degradation mechanisms affecting the integrity of piping systems. This paper discusses the integrity assessment of wall-thinned feeder pipes using limit load analysis. Based on finite element limit analyses, this paper compare limit loads for wall-thinning feeder pipes under combined bending and internal pressure with proposed limit loads. The limit loads are determined from limit analyses based on rectangular wall-thinning and elastic-perfectly-plastic materials using the large geometry change.

Copper thin film for RFID UHF antenna on flexible substrate

International Nuclear Information System (INIS)

Tran, Nhan Ai; Tran, Huy Nam; Dang, Mau Chien; Fribourg-Blanc, Eric

2010-01-01

A process flow using photolithography and sputtering was studied for copper antenna fabrication on thin poly(ethylene terephthalate) (PET) substrate. The lift-off route was chosen for its flexibility at laboratory scale. It was clarified that the cleaning of PET is an important step that necessitates mild oxygen plasma etching. Then copper is sputter deposited after photolithographic definition of the antenna. Care is necessary since PET, as a very flexible substrate, is temperature sensitive. The temperature increase generated by the impact of deposited copper should be maintained below the glass transition temperature of the polymer to avoid detrimental deformation. dc power of 40 to 50 W was found to be the maximum possible sputtering power for commercial PET. It was found that the resistivity of the thin film is below two times the bulk resistivity of copper for a deposition pressure below 4×10 −3  mbar and thickness above 450 nm. These results enable the reliable fabrication of copper RFID UHF antennae on a PET substrate for further testing of new tag designs. The present paper summarizes the effort to test new designs of antennae for RadioFrequency IDentification (RFID) Ultra High Frequency (UHF) tags, for use in various applications (e.g. object tracking and environment monitoring) in Vietnam

Feeder cells support the culture of induced pluripotent stem cells even after chemical fixation.

Directory of Open Access Journals (Sweden)

Xiao-Shan Yue

Full Text Available Chemically fixed mouse embryonic fibroblasts (MEFs, instead of live feeder cells, were applied to the maintenance of mouse induced pluripotent stem (miPS cells. Formaldehyde and glutaraldehyde were used for chemical fixation. The chemically fixed MEF feeders maintained the pluripotency of miPS cells, as well as their undifferentiated state. Furthermore, the chemically fixed MEF feeders were reused several times without affecting their functions. These results indicate that chemical fixation can be applied to modify biological feeders chemically, without losing their original functions. Chemically fixed MEF feeders will be applicable to other stem cell cultures as a reusable extracellular matrix candidate that can be preserved on a long-term basis.

Assessment of immunomodulating action of combined therapy with UHF-hyperthermia in children with osteogenic sarcoma

International Nuclear Information System (INIS)

Neprina, G.S.; Panteleeva, E.S.; Vatin, O.E.; Bizer, V.A.; Bojko, I.N.

1989-01-01

The paper is concerned with immunological evaluation of different stages of combined therapy with local UHF-hyperthermia in children with osteogenic sarcoma. Combined therapy (polychemo- and raditherapy) was shown to cause a decrease in the number of immunocompetent cells, to enhance dysbalance of immunoregulatory T-lymphocytes, to weaken T-lymphocyte function on PHA; immunosuppressive action of combined therapy did not depend on a tumor site. The incorporation of UHF-hyperthermia in the therapeutic scheme weakened the manifestations of secondary immunodeficiency, got back to normal structure of T-lymphocyte population. A favorable immunomodulating effect of hyperthermia was more frequently observed in patients with crural bone tumors. The effect of hyperthermia was revealed after direct influence of thermotherapy but it was absent in continuation of combined treatment

Frequency dependent steering with backward leaky waves via photonic crystal interface layer.

Science.gov (United States)

Colak, Evrim; Caglayan, Humeyra; Cakmak, Atilla O; Villa, Alessandro D; Capolino, Filippo; Ozbay, Ekmel

2009-06-08

A Photonic Crystal (PC) with a surface defect layer (made of dimers) is studied in the microwave regime. The dispersion diagram is obtained with the Plane Wave Expansion Method. The dispersion diagram reveals that the dimer-layer supports a surface mode with negative slope. Two facts are noted: First, a guided (bounded) wave is present, propagating along the surface of the dimer-layer. Second, above the light line, the fast traveling mode couple to the propagating spectra and as a result a directive (narrow beam) radiation with backward characteristics is observed and measured. In this leaky mode regime, symmetrical radiation patterns with respect to the normal to the PC surface are attained. Beam steering is observed and measured in a 70 degrees angular range when frequency ranges in the 11.88-13.69 GHz interval. Thus, a PC based surface wave structure that acts as a frequency dependent leaky wave antenna is presented. Angular radiation pattern measurements are in agreement with those obtained via numerical simulations that employ the Finite Difference Time Domain Method (FDTD). Finally, the backward radiation characteristics that in turn suggest the existence of a backward leaky mode in the dimer-layer are experimentally verified using a halved dimer-layer structure.

Middle School Girls and the "Leaky Pipeline" to Leadership

Science.gov (United States)

Shapiro, Mary; Grossman, Diane; Carter, Suzanne; Martin, Karyn; Deyton, Patricia; Hammer, Diane

2015-01-01

Why do girls perform so well academically yet lose ground as professional women? This diminishing number of women up the leadership hierarchy is often referred to as the "leaky pipeline," and attributed to many factors: external ones such as work environments not conducive to work/life balance, and internal ones such as women's own…

Seismic analysis of ITER fourth PF (Poloidal Field Coil) feeder

International Nuclear Information System (INIS)

Liu, Sumei; Chen, Wei; Song, Yuntao; Ni, Xiaojun; Wang, Zhongwei; Chen, Yonghua; Gong, Chenyu

2014-01-01

The ITER feeder systems connect the ITER magnet systems located inside the main cryostat to the cryo-plant, power-supply and control system interfaces outside the cryostat. The main purpose of the feeders is to convey the cryogenic supply and electrical power to the coils as well as house the instrumentation wiring. The PF busbar which carries 52 kA current will suffer from high Lorentz force due to the background magnetic field inspired by the coils and the self-field between every pair of busbars. Except their mechanical strength and thermal insulation performance must be achieved, the dynamic mechanism on PF structure should be assessed. This paper presents the simulation and seismic analysis on ITER 4th PF feeder including the Coil Terminal Box and S-bend Box (CTB and SBB), the Cryostat Feed-through (CFT), the In-Cryostat-Feeder (ICF), especially for the ground supports and main outer-tube firstly. This analysis aims to study seismic resistance on system design under local seismograms with floor response spectrum, the structural response vibration mode and response duration results of displacement, membrane stress, and bending stress on structure under different directions actuating signals were obtained by using the single-seismic spectrum analysis and Dead Weight analysis respectively. Based on the simulative and analytical results, the system seismic resistance and the integrity of the support structure in the 4th PF feeder have been studied and the detail design confirmed

Improvement of Local Voltage in Feeders with Photovoltaic using Electric Vehicles

DEFF Research Database (Denmark)

Marra, Francesco; Yang, Guangya; Fawzy, Y. T.

2013-01-01

In low-voltage (LV) feeders with high penetration of photovoltaic (PV), a major issue to be solved is voltage rise due to the active power injection. If no measures are taken, this may lead to generation’s interruptions and to the malfunctioning of domestic appliances due to non-standard voltage...... profiles. This paper proposes a storage strategy to alleviate voltage rise in feeders with PV, using coordinated electric vehicle (EV) load as the storage solution. The voltage support strategy is easy to implement practically and it is demonstrated on a test feeder emulating a household with roof...

Performance and Benchmarking of Multisurface UHF RFID Tags for Readability and Reliability

Directory of Open Access Journals (Sweden)

Joshua Bolton

2017-01-01

Full Text Available As the price of passive radio frequency identification (RFID tags continues to decrease, more and more companies are considering item-level tagging. Although the use of RFID is simple, its proper application should be studied to achieve maximum efficiency and utilization in the industry. This paper is intended to demonstrate the test results of various multisurface UHF tags from different manufacturers for their readability under varying conditions such as orientation of tags with respect to reader, distance of tag from the reader, and materials used for embedding tags. These conditions could affect the reliability of RFID systems used for varied applications. In this paper, we implement a Design for Six Sigma Research (DFSS-R methodology that allows for reliability testing of RFID systems. In this paper, we have showcased our results about the benchmarking of UHF RFID tags and have put forward an important observation about the blind spots observed at different distances and orientations along different surfaces, which is primarily due to the polarity of the antenna chosen.

Decision Support for Optimal Repositioning of Containers in a Feeder System

Directory of Open Access Journals (Sweden)

Danijela Tuljak-Suban

2008-03-01

Full Text Available The transport of empty containers represents a seriousproblem in the fast growing sphere of maritime container transport.The most widespread type of container transport organizationin maritime transport is the hub and spoke mode, whichenables the transport of a great number of containers via largevessels between hub ports, from where feeder ships transport tosmaller ports that thus gravitate to the central hub port. The articlecontains a detailed analysis of the northern Adriatic portsand the feeder connections with the hub ports of the Mediterranean.A two-level VRPPD (Vehicle Routing Problem withPickup and Delivery problem is modelled on a graph, wherethe transport of full containers is privileged over the transport ofempty containers. This enables the simulation of the feeder systemin the n01them Adriatic, meaning that it shows the ship'soperator the movement programme with minimal transportcosts for the superfluous empty containers in the complex of theregular transports of full containers in the feeder system.

Resonant absorption in semiconductor nanowires and nanowire arrays: Relating leaky waveguide modes to Bloch photonic crystal modes

Energy Technology Data Exchange (ETDEWEB)

Fountaine, Katherine T., E-mail: kfountai@caltech.edu [Department of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States); Joint Center for Artificial Photosynthesis, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States); Whitney, William S. [Joint Center for Artificial Photosynthesis, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States); Department of Physics, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States); Atwater, Harry A. [Joint Center for Artificial Photosynthesis, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States); Department of Applied Physics and Materials Science, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125 (United States)

2014-10-21

We present a unified framework for resonant absorption in periodic arrays of high index semiconductor nanowires that combines a leaky waveguide theory perspective and that of photonic crystals supporting Bloch modes, as array density transitions from sparse to dense. Full dispersion relations are calculated for each mode at varying illumination angles using the eigenvalue equation for leaky waveguide modes of an infinite dielectric cylinder. The dispersion relations along with symmetry arguments explain the selectivity of mode excitation and spectral red-shifting of absorption for illumination parallel to the nanowire axis in comparison to perpendicular illumination. Analysis of photonic crystal band dispersion for varying array density illustrates that the modes responsible for resonant nanowire absorption emerge from the leaky waveguide modes.

A Markov chain model for CANDU feeder pipe degradation

International Nuclear Information System (INIS)

Datla, S.; Dinnie, K.; Usmani, A.; Yuan, X.-X.

2008-01-01

There is need for risk based approach to manage feeder pipe degradation to ensure safe operation by minimizing the nuclear safety risk. The current lack of understanding of some fundamental degradation mechanisms will result in uncertainty in predicting the rupture frequency. There are still concerns caused by uncertainties in the inspection techniques and engineering evaluations which should be addressed in the current procedures. A probabilistic approach is therefore useful in quantifying the risk and also it provides a tool for risk based decision making. This paper discusses the application of Markov chain model for feeder pipes in order to predict and manage the risks associated with the existing and future aging-related feeder degradation mechanisms. The major challenge in the approach is the lack of service data in characterizing the transition probabilities of the Markov model. The paper also discusses various approaches in estimating plant specific degradation rates. (author)

Climate Prediction Center (CPC) Global Monthly Leaky Bucket Soil Moisture Analysis

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly global soil moisture, runoff, and evaporation data sets produced by the Leaky Bucket model at 0.5? ? 0.5? resolution for the period from 1948 to the present....

Shallow Boomerang-shaped Influenza Hemagglutinin G13A Mutant Structure Promotes Leaky Membrane Fusion*

Science.gov (United States)

Lai, Alex L.; Tamm, Lukas K.

2010-01-01

Our previous studies showed that an angled boomerang-shaped structure of the influenza hemagglutinin (HA) fusion domain is critical for virus entry into host cells by membrane fusion. Because the acute angle of ∼105° of the wild-type fusion domain promotes efficient non-leaky membrane fusion, we asked whether different angles would still support fusion and thus facilitate virus entry. Here, we show that the G13A fusion domain mutant produces a new leaky fusion phenotype. The mutant fusion domain structure was solved by NMR spectroscopy in a lipid environment at fusion pH. The mutant adopted a boomerang structure similar to that of wild type but with a shallower kink angle of ∼150°. G13A perturbed the structure of model membranes to a lesser degree than wild type but to a greater degree than non-fusogenic fusion domain mutants. The strength of G13A binding to lipid bilayers was also intermediate between that of wild type and non-fusogenic mutants. These membrane interactions provide a clear link between structure and function of influenza fusion domains: an acute angle is required to promote clean non-leaky fusion suitable for virus entry presumably by interaction of the fusion domain with the transmembrane domain deep in the lipid bilayer. A shallower angle perturbs the bilayer of the target membrane so that it becomes leaky and unable to form a clean fusion pore. Mutants with no fixed boomerang angle interacted with bilayers weakly and did not promote any fusion or membrane perturbation. PMID:20826788

A novel method for decomposing electricity feeder load into elementary profiles from customer information

International Nuclear Information System (INIS)

Gerossier, Alexis; Barbier, Thibaut; Girard, Robin

2017-01-01

Highlights: •Use of aggregated electricity load profiles and customer description at feeder level. •Statistical recovery of elementary load profiles with customer categorization. •Generation of load demand profiles for unknown feeders and new local areas. •Relevancy of the different categorizations. -- Abstract: To plan a distribution grid involves making a long-term forecast of sub-hourly demand, which requires modeling the demand and its dynamics with aggregated measurement data. Distribution system operators (DSOs) have been recording electricity sub-hourly demand delivered by their medium-voltage feeders (around 1000—10,000 customers) for several years. Demand profiles differ widely among the various considered feeders. This is partly due to the varying mix of customer categories from one feeder to another. To overcome this issue, elementary demand profiles are often associated with customer categories and then combined according to a mix description. This paper presents a novel method to estimate elementary profiles that only requires several feeder demand curves and a description of customers. The method relies on a statistical blind source model and a new estimation procedure based on the augmented Lagrangian method. The use of feeders to estimate elementary profiles means that measurements are fully representative and continuously updated. We illustrate the proposed method through a case study comprising around 1000 feeder demand curves operated by the main French DSO Enedis. We propose an application o that uses the obtained profiles to evaluate the contribution of any set of new customers to a feeder peak load. We show that profiles enable a simulation of new unmeasured areas with errors of around 20%. We also show how our method can be used to evaluate the relevancy of different customer categorizations.

Leukemic Cells "Gas Up" Leaky Bone Marrow Blood Vessels.

Science.gov (United States)

Itkin, Tomer; Rafii, Shahin

2017-09-11

In this issue of Cancer Cell, Passaro et al. demonstrate how leukemia through aberrant induction of reactive oxygen species and nitric oxide production trigger marrow vessel leakiness, instigating pro-leukemic function. Disrupted tumor blood vessels promote exhaustion of non-malignant stem and progenitor cells and may facilitate leukemia relapse following chemotherapeutic treatment. Copyright © 2017. Published by Elsevier Inc.

Leaky-box approximation to the fractional diffusion model

International Nuclear Information System (INIS)

Uchaikin, V V; Sibatov, R T; Saenko, V V

2013-01-01

Two models based on fractional differential equations for galactic cosmic ray diffusion are applied to the leaky-box approximation. One of them (Lagutin-Uchaikin, 2000) assumes a finite mean free path of cosmic ray particles, another one (Lagutin-Tyumentsev, 2004) uses distribution with infinite mean distance between collision with magnetic clouds, when the trajectories have form close to ballistic. Calculations demonstrate that involving boundary conditions is incompatible with spatial distributions given by the second model.

Comparison of UHF measurements with the propagation model of Recommendation ITU-R P.1546

NARCIS (Netherlands)

Witvliet, B.A.; Wijninga, P.W.; van Maanen, E.; Smith, B.

2010-01-01

This report describes a radio propagation measurement campaign that has been performed along paths between the Netherlands and the United Kingdom. The campaign focused on UHF propagation on mixed land/sea paths. Special attention was given to calibration accuracy and validation of the measurement

BC Hydro's integrated approach on replacing underground feeder cables

Energy Technology Data Exchange (ETDEWEB)

Tarampi, D. [BC Hydro, Burnaby, BC (Canada)

2008-07-01

BC Hydro's integrated approach on replacing underground feeder cables was discussed. The feeder cables were all in ducts encased in concrete and splices were identified in concrete manholes. The feeder cables averaged 35 to 40 failures per year, with a large majority of failures occurring in manholes or near terminations. The age of the cables was not known. A graphical representation of a condition assessment was presented with reference to an electrical test, metallurgical test, hardness test, and dye penetrating test. Prioritization steps were also listed, including a condition index and replacement threshold. Steps in prioritizing the condition index included determining the insulation index based on electrical test results; determining the manhole condition based on metallurgical test results; determining the customer importance factor and feeder load factor; and calculating the overall condition index based on the indices. A process flowchart was also illustrated. A replacement strategy was then discussed and a cost comparison of two options was described. Option 1 was to replace only the unjacketed cables while option two involved selective replacement. tabs., figs.

GPM GROUND VALIDATION NOAA UHF 449 PROFILER RAW DATA SPC FORMAT MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The NOAA UHF 449 Profiler Raw SPC foramt data was collected during the NASA supported Midlatitude Continental Convective Clouds Experiment (MC3E). The Ultra High...

GPM GROUND VALIDATION NOAA UHF 449 PROFILER RAW DATA SPC FORMAT MC3E V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation NOAA UHF 449 Profiler Raw Data SPC Format MC3E dataset was collected during the NASA supported Midlatitude Continental Convective Clouds...

Investigating Feasibility of Multiple UHF Passive RFID Transmitters Using Backscatter Modulation Scheme in BCI Applications

DEFF Research Database (Denmark)

Al Ajrawi, Shams; Sarkar, Mahasweta; Mihovska, Albena

Building a wireless body area network (WBAN) application including implantable transceivers placed inside the human brain to collect the data from the electrodes and transmit them wirelessly to a controller placed outside the brain on the scalp faced major challenges. The transmission...... using passive RFID as the implantable transmitters and letting them operate in the UHF range. Backscatter modulation has been used as a power transfer mechanism. Investigation on the feasibility and applicability of implantable UHF Passive RFID transmitters inside the brain is done for capturing multi......-channel ECoG signals when traversing through a phantom brain model as a transmission medium for the experiments at a high data transfer rate. Detailed analysis has been done on parameters such as Received Signal Strength Indication (RSSI), signal to noise ratio (SNR), Maximum number of electrodes, Path Loss...

Leaky vessels as a potential source of stromal acidification in tumours

KAUST Repository

Martin, Natasha K.; Gaffney, Eamonn A.; Gatenby, Robert A.; Maini, Philip K.

2010-01-01

results found in vivo with a tumour implanted in the mammary fat pad of a mouse in a window chamber construct. We find that leaky vasculature can cause a net acidification of the normal tissue away from the tumour boundary, though not a progressive

Expression and secretory profile of buffalo fetal fibroblasts and Wharton's jelly feeder layers.

Science.gov (United States)

Parmar, Mehtab S; Mishra, Smruti Ranjan; Somal, Anjali; Pandey, Sriti; Kumar, G Sai; Sarkar, Mihir; Chandra, Vikash; Sharma, G Taru

2017-05-01

The present study examined the comparative expression and secretory profile of vital signaling molecules in buffalo fetal fibroblasts (BFF) and Wharton's jelly (BWJ) feeder layers at different passages. Both feeder layers were expanded up to 8th passage. Signaling molecules viz. bone morphogenetic protein 4 (BMP4), fibroblast growth factor 2 (FGF2), leukemia inhibitory factor (LIF) and transforming growth factor beta 1 (TGFB1) and pluripotency-associated transcriptional factors (POU5F1, SOX2, NANOG, KLF4, MYC and FOXD3) were immunolocalized in the both feeder types. A clear variation in the expression pattern of key signaling molecules with passaging was registered in both feeders compared to primary culture (0 passage). The conditioned media (CM) was collected from different passages (2, 4, 6, 8) of both the feeder layers and was quantified using enzyme-linked immunosorbent assay (ELISA). Concomitant to expression profile, protein quantification also revealed differences in the concentration of signaling molecules at different time points. Conjointly, expression and secretory profile revealed that 2nd passage of BFF and 6th passage of BWJ exhibit optimal levels of key signaling molecules thus may be selected as best passages for embryonic stem cells (ESCs) propagation. Further, the effect of mitomycin-C (MMC) treatment on the expression profile of signaling molecules in the selected passages of BFF and BWJ revealed that MMC modulates the expression profile of these molecules. In conclusion, the results indicate that feeder layers vary in expression and secretory pattern of vital signaling molecules with passaging. Based on these findings, the appropriate feeder passages may be selected for the quality propagation of buffalo ESCs. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparing the engineering program feeders from SiF and convention models

Science.gov (United States)

Roongruangsri, Warawaran; Moonpa, Niwat; Vuthijumnonk, Janyawat; Sangsuwan, Kampanart

2018-01-01

This research aims to compare the relationship between two types of engineering program feeder models within the technical education systems of Rajamangala University of Technology Lanna (RMUTL), Chiangmai, Thailand. To illustrate, the paper refers to two typologies of feeder models, which are the convention and the school in factory (SiF) models. The new SiF model is developed through a collaborative educational process between the sectors of industry, government and academia, using work-integrated learning. The research methodology were use to compared features of the the SiF model with conventional models in terms of learning outcome, funding budget for the study, the advantages and disadvantages from the point of view of students, professors, the university, government and industrial partners. The results of this research indicate that the developed SiF feeder model is the most pertinent ones as it meet the requirements of the university, the government and the industry. The SiF feeder model showed the ability to yield positive learning outcomes with low expenditures per student for both the family and the university. In parallel, the sharing of knowledge between university and industry became increasingly important in the process, which resulted in the improvement of industrial skills for professors and an increase in industrial based research for the university. The SiF feeder model meets its demand of public policy in supporting a skilled workforce for the industry, which could be an effective tool for the triple helix educational model of Thailand.

Analysis of Leaky Modes in Photonic Crystal Fibers Using the Surface Integral Equation Method

Directory of Open Access Journals (Sweden)

Jung-Sheng Chiang

2018-04-01

Full Text Available A fully vectorial algorithm based on the surface integral equation method for the modelling of leaky modes in photonic crystal fibers (PCFs by solely solving the complex propagation constants of characteristic equations is presented. It can be used for calculations of the complex effective index and confinement losses of photonic crystal fibers. As complex root examination is the key technique in the solution, the new algorithm which possesses this technique can be used to solve the leaky modes of photonic crystal fibers. The leaky modes of solid-core PCFs with a hexagonal lattice of circular air-holes are reported and discussed. The simulation results indicate how the confinement loss by the imaginary part of the effective index changes with air-hole size, the number of rings of air-holes, and wavelength. Confinement loss reductions can be realized by increasing the air-hole size and the number of air-holes. The results show that the confinement loss rises with wavelength, implying that the light leaks more easily for longer wavelengths; meanwhile, the losses are decreased significantly as the air-hole size d/Λ is increased.

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

Science.gov (United States)

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-12-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

An evaluation of the choice of feeder cell growth arrest for the production of cultured epidermis.

Science.gov (United States)

Chugh, Rishi Man; Chaturvedi, Madhusudan; Yerneni, Lakshmana Kumar

2015-12-01

Growth arrested 3T3 cells have been used as feeder cells in human epidermal keratinocyte cultures to produce cultured epidermal autografts for the treatment of burns. The feeder cells were ideally growth-arrested by gamma-irradiation. Alternatively, growth arrest by mitomycin C treatment is a cost effective option. We compared the functional efficacy of these two approaches in keratinocyte cultures by colony forming efficiency, the net growth area of colonies, BrdU labeling and histological features of cultured epidermal sheets. The growth area estimation involved a semi-automated digital technique using the Adobe Photoshop and comprised of isolation and enumeration of red pixels in Rhodamine B-stained keratinocyte colonies. A further refinement of the technique led to the identification of critical steps to increasing the degree of accuracy and enabling its application as an extension of colony formation assay. The results on feeder cell functionality revealed that the gamma irradiated feeders influenced significantly higher colony forming efficiency and larger growth area than the mitomycin C treated feeders. The BrdU labeling study indicated significant stimulation of the overall keratinocyte proliferation by the gamma irradiated feeders. The cultured epidermal sheets produced by gamma feeders were relatively thicker than those produced by mitomycin C feeders. We discussed the clinical utility of mitomycin C feeders from the viewpoint of cost-effective burn care in developing countries. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

VHF/UHF imagery and RCS measurements of ground targets in forested terrain

Science.gov (United States)

Gatesman, Andrew J.; Beaudoin, Christopher J.; Giles, Robert H.; Waldman, Jerry; Nixon, William E.

2002-08-01

The monostatic VV and HH-polarized radar signatures of several targets and trees have been measured at foliage penetration frequencies (VHF/UHF) by using 1/35th scale models and an indoor radar range operating at X-band. An array of high-fidelity scale model ground vehicles and test objects as well as scaled ground terrain and trees have been fabricated for the study. Radar measurement accuracy has been confirmed by comparing the signature of a test object with a method of moments radar cross section prediction code. In addition to acquiring signatures of targets located on a smooth, dielectric ground plane, data have also been acquired with targets located in simulated wooded terrain that included scaled tree trunks and tree branches. In order to assure the correct backscattering behavior, all dielectric properties of live tree wood and moist soil were scaled properly to match the complex dielectric constant of the full-scale materials. The impact of the surrounding tree clutter on the VHF/UHF radar signatures of ground vehicles was accessed. Data were processed into high-resolution, polar-formatted ISAR imagery and signature comparisons are made between targets in open-field and forested scenarios.

Un sistema RFID in banda UHF per l'autoprestito in Biblioteca

OpenAIRE

Ricci, Franco; Crisanti, Andrea

2009-01-01

Department of Physics and CASPUR have been starting, in the past 2 years, a collaborationin order to develop a new RFID (Radio Frequency IDentification) system for automaticlibrary loan procedures. These systems (generally known as self-checkequipments) uses radio signals in the UHF frequency range to interact with antennas(passive tags) used to identify books. Users identification is made through special cardswith an embedded tag. The entire loan process is completely managed by users throug...

Effect of artificial feeders on pollen loads of the hummingbirds of Cerro de La Muerte, Costa Rica

Directory of Open Access Journals (Sweden)

Gerardo Avalos

2012-03-01

Full Text Available Although sugar-water feeders are commonly used by enthusiasts to attract hummingbirds, little is known about how they affect hummingbird behavior and flower use. We studied the highland hummingbird assemblage of Cerro de La Muerte, Costa Rica, both at a site with permanent feeders (La Georgina Restaurant and further from it. We examined how feeder use and monopolization affected seasonal changes in pollen loads during four sampling periods, including dry and wet seasons, from 2003-2005. We expected that species monopolizing the feeders would carry little or no pollen whatsoever, and would have pollen loads characterized by low floral diversity, in contrast with species less dependent on feeders. We obtained pollen samples from 183 individuals of four hummingbird species captured around the feeders using mist nets, which were compared with a pollen reference collection of plants with a pollination syndrome by hummingbirds. The same methods were implemented at a site 3km away from the feeders. Feeder usage was quantified by counting the number of times hummingbirds drank from the feeders in periods of 4min separated by 1min. The effects of hummingbird species and season on pollen load categories were assessed using a nominal logistic regression. The alpha species at the site, the Fiery-throated Hummingbird (Panterpe insignis, dominated the feeders during the dry season. Meanwhile, in the wet season, feeder usage was more evenly distributed across species, with the exception of the Volcano Hummingbird, Selasphorus flammula, which occupies the last place in the dominance hierarchy. Pollen loads of hummingbirds captured near feeders were low in abundance (more than 50% of captured individuals had zero or low pollen loads, and low in species richness (96% of the hummingbirds with pollen from only one plant genus, Centropogon. Overall pollen loads increased during the dry season coinciding with peaks in flower availability, although the majority of

Effect of artificial feeders on pollen loads of the hummingbirds of Cerro de la Muerte, Costa Rica.

Science.gov (United States)

Avalos, Gerardo; Soto, Alejandra; Alfaro, Willy

2012-03-01

Although sugar-water feeders are commonly used by enthusiasts to attract hummingbirds, little is known about how they affect hummingbird behavior and flower use. We studied the highland hummingbird assemblage of Cerro de La Muerte, Costa Rica, both at a site with permanent feeders (La Georgina Restaurant) and further from it. We examined how feeder use and monopolization affected seasonal changes in pollen loads during four sampling periods, including dry and wet seasons, from 2003-2005. We expected that species monopolizing the feeders would carry little or no pollen whatsoever, and would have pollen loads characterized by low floral diversity, in contrast with species less dependent on feeders. We obtained pollen samples from 183 individuals of four hummingbird species captured around the feeders using mist nets, which were compared with a pollen reference collection of plants with a pollination syndrome by hummingbirds. The same methods were implemented at a site 3km away from the feeders. Feeder usage was quantified by counting the number of times hummingbirds drank from the feeders in periods of 4min separated by 1min. The effects of hummingbird species and season on pollen load categories were assessed using a nominal logistic regression. The alpha species at the site, the Fiery-throated Hummingbird (Panterpe insignis), dominated the feeders during the dry season. Meanwhile, in the wet season, feeder usage was more evenly distributed across species, with the exception of the Volcano Hummingbird, Selasphorus flammula, which occupies the last place in the dominance hierarchy. Pollen loads of hummingbirds captured near feeders were low in abundance (more than 50% of captured individuals had zero or low pollen loads), and low in species richness (96% of the hummingbirds with pollen from only one plant genus, Centropogon). Overall pollen loads increased during the dry season coinciding with peaks in flower availability, although the majority of captured

Optimal Design of the Feeder-Bus Network Based on the Transfer System

Directory of Open Access Journals (Sweden)

Lianbo Deng

2013-01-01

Full Text Available This paper studied the classic feeder-bus network design problem (FBNDP, which can be described as follows: for the passenger travel demand between rail stations and bus stops on a given urban transit network, it designs the optimal feeder bus routes and frequencies so as to minimize the passengers’ travel expense and the operator’s cost. We extended the demand pattern of M-to-1 in most existing researches to M-to-M. We comprehensively considered the passenger travel cost, which includes the waiting and riding cost on the bus, riding cost on rail, and transfer cost between these two transportation modes, and presented a new genetic algorithm that determines the optimal feeder-bus operating frequencies under strict constraint conditions. The numerical examples under different demand patterns have been experienced and analysed, which showed the robustness and efficiency of the presented algorithm. We also found that the distribution pattern of the travel demand has a significant influence on the feeder-bus network construction.

Resonance of conductivity in UHF-range to the action of alternating current in La0.7Pb0.3MnO3 crystals

International Nuclear Information System (INIS)

Volkov, N.V.; Petrakovskij, G.A.; Sablina, K.A.

1999-01-01

The experimental results of the study on the effect of the low frequency transport current on the conductivity in UHF-range of the La 0.7 Pb 0.3 MnO 3 monocrystals are presented. In absence of the external magnetic field the UHF-conductivity response signal on the current impact has the form of the relaxation process. The peak of the amplitude resonance growth is observed in the external magnetic field in the response spectrum. The resonance response is of nonlinear character. The temperature and field dependences of the UHF-response basic parameters are in direct correlation with the magnetoresistance behaviour. The results obtained are analyzed within the frames of the oscillatory approximation. The mechanism of the phases electron separation is proposed as the possible mechanism of the current impact [ru

Mass transfer effects in feeder flow-accelerated corrosion wall thinning

International Nuclear Information System (INIS)

Pietralik, J.

2008-01-01

Flow conditions play a dominant role in Flow-Accelerated Corrosion (FAC) under certain conditions, e.g., in CANDU feeders. While chemistry and materials set the overall potential for FAC, flow conditions determine the local distribution of wall thinning. Recent plant data of feeders and laboratory tests confirms that there is a close relationship between local flow conditions, expressed by mass transfer coefficient, and FAC rate in CANDU feeder bends. The knowledge of local effects can be useful for minimizing the number of inspected components, predicting the location of the highest FAC rate for a given piping component, and determining what components or feeders should be replaced. A similar evaluation applies also to FAC in heat transfer equipment such as heat exchangers and steam generators. The objective of this paper is to examine the relationship between FAC rate and local mass transfer parameters. For FAC where the flow is dominant, the FAC rate is proportional to mass flux of ferrous ions. The mass flux is the product of the mass transfer coefficient and the concentration difference, or degree of saturation. The mass transfer coefficient describes the intensity of the transport of corrosion products (ferrous ions) from the oxide-water interface into the bulk water. Therefore, this parameter can be used for predicting the local distribution of FAC rate in the mass-transfer controlled FAC. The degree of saturation reduces the mass flux, thus reducing the FAC rate. This effect can be significant in long piping, e.g., in outlet feeders. The paper presents plant and laboratory evidence for the relationship between local mass transfer conditions and the FAC rate. It shows correlations for mass transfer coefficient in components that are highly susceptible to FAC and most important flow parameters that affect mass transfer coefficient. The role of surface roughness, wall shear stress, and local turbulence is also discussed. (author)

Evaluation of options for life cycle management of feeder cracking at the Point Lepreau Generating Station

International Nuclear Information System (INIS)

Gendron, T.S.; Slade, J.P.

2003-01-01

The CANDU industry has a predictive capability for most Heat Transport System (HTS) degradation issues that allows utilities to apply cost-effective maintenance programs. The standard approach for maintenance programs is focussed inspection and planned replacement. Some examples of degradation issues with deterministic failure rates are feeder thinning, and pressure tube elongation and deuterium ingress. However, the cracking observed in Point Lepreau Generating Station (PLGS) outlet feeder first bends is one notable exception to this behaviour. A predictive capability for feeder cracking does not currently exist for several reasons. First, the mechanism of feeder cracking, stress corrosion cracking (SCC), has to some degree a random nature. Second, although a probable environment causing cracking has been identified, the precise stress and environmental conditions for feeder crack initiation and propagation have not been defined. Finally, the very low incidence of feeder cracking observed to-date (four, all at PLGS) precludes a probabilistic or statistical prediction of failure rate. Generally, utilities select a Life Cycle Management Plan that ensures safe operation and has the lowest Net Present Value cost. In preparing a Feeder Life Cycle Management Plan, New Brunswick Power (NBP) has recognized that the Net Present Value cost is very sensitive to failure rate. Since the failure rate for feeder cracking is not well defined, the following three scenarios were considered to bound the probability of future failures at PLGS. (author)

Computational fluid dynamics analysis for flow accelerated corrosion in CANDU6 feeder pipes

International Nuclear Information System (INIS)

Catana, A.; Pauna, E.; Ioan, M.

2013-01-01

CANDU6 plant management over a long time period includes various ageing and degradation mechanisms like FAC manifested mainly at first and second elbow of CANDU6 outlet feeders. FAC take place at all CANDU6 built before 2000 year with feeders made from SA106 grade B low alloy carbon-steel (with chromium at 0.02%). CFD method is used in this paper to investigate the feeder's wall thinning process taking place mainly due local flow conditions in complex 3D geometrical configurations. The 380 outlet feeders grouped in 2.5'' (320) and 2.0'' feeders (60). The objective of this paper is to help, as much as possible, to focus investigation on most probable maximum thinning rate locations through 3D distribution of some TH parameters. Application of CFD methods in CANDU6 nuclear reactors implies the knowledge of real plant operating data like: long term time averaged channel power and mass flow as well as temperature, pressure, pHa etc allowing the optimization and cost reduction of wall thinning monitoring process at CANDU6 nuclear power plants. (authors)

UHF RFID tag implementation on cork substrate for wine bottle monitoring

OpenAIRE

Rima Martí, Sergi; Georgiadis, Apostolos

2013-01-01

Wine industry is starting to deploy RFID technology for production control, logistics or innovative marketing. However, identifying wine bottles is difficult due to the unfavorable material content for the operation of the antennas. The thesis consists on the implementation of a UHF RFID tag placed on cork substrate in order to provide a feasible way of identifying wine packaged bottle. The proposed RFID tag consists on a meandered line dipole antenna, designed to be conformed so that it can ...

Disordered redox metabolism of brain cells in rats exposed to low doses of ionizing radiation or UHF electromagnetic radiation.

Science.gov (United States)

Burlaka, A P; Druzhyna, M O; Vovk, A V; Lukin, S М

2016-12-01

To investigate the changes of redox-state of mammalian brain cells as the critical factor of initiation and formation of radiation damage of biological structures in setting of continuous exposure to low doses of ionizing radiation or fractionated ultra high frequency electromagnetic radiation (UHF EMR) at non-thermal levels. The influence of low-intensity ionizing radiation was studied on outbred female rats kept for 1.5 years in the Chernobyl accident zone. The effects of total EMR in the UHF band of non-thermal spectrum were investigated on Wistar rats. The rate of formation of superoxide radicals and the rate of NO synthesis in mitochondria were determined by the EPR. After exposure to ionizing or UHF radiation, the levels of ubisemiquinone in brain tissue of rats decreased by 3 and 1.8 times, respectively. The content of NO-FeS-protein complexes in both groups increased significantly (р < 0.05). In the conditions of ionizing or EMR the rates of superoxide radical generation in electron-transport chain of brain cell mitochondria increased by 1.5- and 2-fold, respectively (р < 0.05). In brain tissue of rats kept in the Chernobyl zone, significant increase of NO content was registered; similar effect was observed in rats treated with UHFR (р < 0.05). The detected changes in the electron transport chain of mitochondria of brain cells upon low-intensity irradiation or UHF EMR cause the metabolic reprogramming of cell mitochondria that increases the rate of superoxide radical generation and nitric oxide, which may initiate the development of neurodegenerative diseases and cancer. This article is part of a Special Issue entitled "The Chornobyl Nuclear Accident: Thirty Years After".

FSL based estimation of white space availability in UHF TV bands in Bergvliet, South Africa

CSIR Research Space (South Africa)

Lysko, AA

2012-09-01

Full Text Available in the UHF TV frequency bands. The free space loss (FSL) formula, together with a line of sight condition, are applied to the information about the location and power of TV transmitters around this area. The predictions show 61% correlation between...

Learning Sparse Visual Representations with Leaky Capped Norm Regularizers

OpenAIRE

Wangni, Jianqiao; Lin, Dahua

2017-01-01

Sparsity inducing regularization is an important part for learning over-complete visual representations. Despite the popularity of $\\ell_1$ regularization, in this paper, we investigate the usage of non-convex regularizations in this problem. Our contribution consists of three parts. First, we propose the leaky capped norm regularization (LCNR), which allows model weights below a certain threshold to be regularized more strongly as opposed to those above, therefore imposes strong sparsity and...

A feeder-free culture using autogeneic conditioned medium for undifferentiated growth of human embryonic stem cells: Comparative expression profiles of mRNAs, microRNAs and proteins among different feeders and conditioned media

Directory of Open Access Journals (Sweden)

Chou Chi-Hsien

2010-10-01

Full Text Available Abstract Background Human embryonic stem (hES cell lines were derived from the inner cell mass of human blastocysts, and were cultured on mouse embryonic fibroblast (MEF feeder to maintain undifferentiated growth, extensive renewal capacity, and pluripotency. The hES-T3 cell line with normal female karyotype was previously used to differentiate into autogeneic fibroblast-like cells (T3HDF as feeder to support the undifferentiated growth of hES-T3 cells (T3/HDF for 14 passages. Results A feeder-free culture on Matrigel in hES medium conditioned by the autogeneic feeder cells (T3HDF was established to maintain the undifferentiated growth of hES-T3 cells (T3/CMHDF for 8 passages in this investigation. The gene expression profiles of mRNAs, microRNAs and proteins between the undifferentiated T3/HDF and T3/CMHDF cells were shown to be very similar, and their expression profiles were also found to be similar to those of T3/MEF and T3/CMMEF cells grown on MEF feeder and feeder-free Matrigel in MEF-conditioned medium, respectively. The undifferentiated state of T3/HDF and T3/CMHDF as well as T3/MEF andT3/CMMEF cells was evidenced by the very high expression levels of "stemness" genes and low expression levels of differentiation markers of ectoderm, mesoderm and endoderm in addition to the strong staining of OCT4 and NANOG. Conclusion The T3HDF feeder and T3HDF-conditioned medium were able to support the undifferentiated growth of hES cells, and they would be useful for drug development and toxicity testing in addition to the reduced risks of xenogeneic pathogens when used for medical applications such as cell therapies.

VHF/UHF radar observations of tropical mesoscale convective systems over southern India

Directory of Open Access Journals (Sweden)

K. Kishore Kumar

2005-07-01

Full Text Available Several campaigns have been carried out to study the convective systems over Gadanki (13.5° N, 79.2° E, a tropical station in India, using VHF and UHF radars. The height-time sections of several convective systems are investigated in detail to study reflectivity, turbulence and vertical velocity structure. Structure and dynamics of the convective systems are the main objectives of these campaigns. The observed systems are classified into single- and multi-cell systems. It has been observed that most of the convective systems at this latitude are multi-cellular in nature. Simultaneous VHF and UHF radar observations are used to classify the observed precipitating systems as convective, intermediary and stratiform regions. Composite height profiles of vertical velocities in these regions were obtained and the same were compared with the profiles obtained at other geographical locations. These composite profiles of vertical velocity in the convective regions have shown their peaks in the mid troposphere, indicating that the maximum latent heat is being released at those heights. These profiles are very important for numerical simulations of the convective systems, which vary significantly from one geographical location to the other.

Keywords. Meteorology and atmospheric dynamics (Mesoscale meteorology; Convective processes – Radio science (Remote sensing

VHF/UHF radar observations of tropical mesoscale convective systems over southern India

Directory of Open Access Journals (Sweden)

K. Kishore Kumar

2005-07-01

Full Text Available Several campaigns have been carried out to study the convective systems over Gadanki (13.5° N, 79.2° E, a tropical station in India, using VHF and UHF radars. The height-time sections of several convective systems are investigated in detail to study reflectivity, turbulence and vertical velocity structure. Structure and dynamics of the convective systems are the main objectives of these campaigns. The observed systems are classified into single- and multi-cell systems. It has been observed that most of the convective systems at this latitude are multi-cellular in nature. Simultaneous VHF and UHF radar observations are used to classify the observed precipitating systems as convective, intermediary and stratiform regions. Composite height profiles of vertical velocities in these regions were obtained and the same were compared with the profiles obtained at other geographical locations. These composite profiles of vertical velocity in the convective regions have shown their peaks in the mid troposphere, indicating that the maximum latent heat is being released at those heights. These profiles are very important for numerical simulations of the convective systems, which vary significantly from one geographical location to the other. Keywords. Meteorology and atmospheric dynamics (Mesoscale meteorology; Convective processes – Radio science (Remote sensing

Partial Discharge Spectral Characterization in HF, VHF and UHF Bands Using Particle Swarm Optimization.

Science.gov (United States)

Robles, Guillermo; Fresno, José Manuel; Martínez-Tarifa, Juan Manuel; Ardila-Rey, Jorge Alfredo; Parrado-Hernández, Emilio

2018-03-01

The measurement of partial discharge (PD) signals in the radio frequency (RF) range has gained popularity among utilities and specialized monitoring companies in recent years. Unfortunately, in most of the occasions the data are hidden by noise and coupled interferences that hinder their interpretation and renders them useless especially in acquisition systems in the ultra high frequency (UHF) band where the signals of interest are weak. This paper is focused on a method that uses a selective spectral signal characterization to feature each signal, type of partial discharge or interferences/noise, with the power contained in the most representative frequency bands. The technique can be considered as a dimensionality reduction problem where all the energy information contained in the frequency components is condensed in a reduced number of UHF or high frequency (HF) and very high frequency (VHF) bands. In general, dimensionality reduction methods make the interpretation of results a difficult task because the inherent physical nature of the signal is lost in the process. The proposed selective spectral characterization is a preprocessing tool that facilitates further main processing. The starting point is a clustering of signals that could form the core of a PD monitoring system. Therefore, the dimensionality reduction technique should discover the best frequency bands to enhance the affinity between signals in the same cluster and the differences between signals in different clusters. This is done maximizing the minimum Mahalanobis distance between clusters using particle swarm optimization (PSO). The tool is tested with three sets of experimental signals to demonstrate its capabilities in separating noise and PDs with low signal-to-noise ratio and separating different types of partial discharges measured in the UHF and HF/VHF bands.

EV Charging Facilities and Their Application in LV Feeders with Photovoltaics

DEFF Research Database (Denmark)

Marra, Francesco; Yang, Guangya; Træholt, Chresten

2013-01-01

Low-voltage (LV) grid feeders with high penetration of photovoltaics (PVs) are often affected by voltage magnitude problems. To solve such issues, previous research has shown that reactive power methods, active power curtailment and grid reinforcement can be used for voltage support, yet showing...... several limits. We introduce the use of electric vehicle (EV) public charging stations with energy storage system (ESS) as a solution for voltage regulation in LV feeders with PV. A novel method is proposed to determine the ESS charging load required for voltage regulation and compare the results...... for the different locations in the feeder. With time-series simulations, we quantify the energy size required for a station ESS. A Belgian LV residential grid, modeled using real PV generation and load profiles, is used as case study. The method and simulation results show the effectiveness of using public EV...

Counseling in the Elementary Feeder Schools.

Science.gov (United States)

Dunham, Virginia

This brief paper presents the concept of transition counseling between a junior high school and its feeder school(s), designed to make the change from elementary into junior high less traumatic. Aside from routine sixth grade counseling, the counselors expanded their base of counseling to include all types of problems as well as all grade levels.…

Configuration System for Simulation Based Design of Vibratory Bowl Feeders

DEFF Research Database (Denmark)

Hansson, Michael Natapon; Mathiesen, Simon; Ellekilde, Lars-Peter

2017-01-01

Vibratory bowl feeders are still among the most commonly used production equipment for automated part feeding, where parts are correctly oriented for further manipulation by being conveyed through a set of orienting devices. Designing vibratory bowl feeders involves selecting and sequencing...... a number of these devices that either reorients or rejects the part until a desirable orientation is achieved. To aid the designer in this task, this work presents a configuration system where knowledge of the behaviour for each device is acquired through dynamic simulation, and used to solve...

Meteor head echo altitude distributions and the height cutoff effect studied with the EISCAT HPLA UHF and VHF radars

Directory of Open Access Journals (Sweden)

A. Westman

2004-04-01

Full Text Available Meteor head echo altitude distributions have been derived from data collected with the EISCAT VHF (224MHz and UHF (930MHz high-power, large-aperture (HPLA radars. At the high-altitude end, the distributions cut off abruptly in a manner reminiscent of the trail echo height ceiling effect observed with classical meteor radars. The target dimensions are shown to be much smaller than both the VHF and the UHF probing wavelengths, but the cutoff heights for the two systems are still clearly different, the VHF cutoff being located several km above the UHF one. A single-collision meteor-atmosphere interaction model is used to demonstrate that meteors in the (1.3–7.2µg mass range will ionise such that critical electron density at 224MHz is first reached at or around the VHF cutoff altitude and critical density at 930MHz will be reached at the UHF cutoff altitude. The observed seasonal variation in the cutoff altitudes is shown to be a function of the seasonal variation of atmospheric density with altitude. Assuming that the electron density required for detection is in the order of the critical density, the abrupt altitude cutoffs can be explained as a consequence of the micrometeoroid joint size-speed distribution dropping off so fast at the large-mass, high-velocity end that above a certain altitude the number of detectable events becomes vanishingly small. Conversely, meteors at the low-mass end of the distribution will be gradually retarded such that the ionisation they generate never reaches critical density. These particles will remain unobservable.Key words. Radio science (instruments and techniques – Interplatery physics (interplanetary dust – General or miscellaneous (new fields

Co-ordination of directional overcurrent protection with load current for parallel feeders

Energy Technology Data Exchange (ETDEWEB)

Wright, J.W.; Lloyd, G.; Hindle, P.J. [Alstom, Inc., Stafford (United Kingdom). T and D Protection and Control

1999-11-01

Directional phase overcurrent relays are commonly applied at the receiving ends of parallel feeders or transformer feeders. Their purpose is to ensure full discrimination of main or back-up power system overcurrent protection for a fault near the receiving end of one feeder. This paper reviews this type of relay application and highlights load current setting constraints for directional protection. Such constraints have not previously been publicized in well-known text books. A directional relay current setting constraint that is suggested in some text books is based purely on thermal rating considerations for older technology relays. This constraint may not exist with modern numerical relays. In the absence of any apparent constraint, there is a temptation to adopt lower current settings with modern directional relays in relation to reverse load current at the receiving ends of parallel feeders. This paper identifies the danger of adopting very low current settings without any special relay feature to ensure protection security with load current during power system faults. A system incident recorded by numerical relays is also offered to highlight this danger. In cases where there is a need to infringe the identified constraints an implemented and testing relaying technique is proposed.

Response of deposit-feeders to exclusion of epibenthic predators in a Mediterranean intertidal flat

NARCIS (Netherlands)

Como, S.; Rossi, F.; Lardicci, C.

2004-01-01

Deposit-feeders are common components of macrofaunal assemblages in intertidal soft sediments. Predation has been considered to have a central role in affecting their distribution and population dynamics. This study investigates the effect of epibenthic predators on deposit-feeders, inhabiting the

"The good into the pot, the bad into the crop!"--a new technology to free stem cells from feeder cells.

Directory of Open Access Journals (Sweden)

Annette Schneider

Full Text Available A variety of embryonic and adult stem cell lines require an initial co-culturing with feeder cells for non-differentiated growth, self renewal and maintenance of pluripotency. However for many downstream ES cell applications the feeder cells have to be considered contaminations that might interfere not just with the analysis of experimental data but also with clinical application and tissue engineering approaches. Here we introduce a novel technique that allows for the selection of pure feeder-freed stem cells, following stem cell proliferation on feeder cell layers. Complete and reproducible separation of feeder and embryonic stem cells was accomplished by adaptation of an automated cell selection system that resulted in the aspiration of distinct cell colonies or fraction of colonies according to predefined physical parameters. Analyzing neuronal differentiation we demonstrated feeder-freed stem cells to exhibit differentiation potentials comparable to embryonic stem cells differentiated under standard conditions. However, embryoid body growth as well as differentiation of stem cells into cardiomyocytes was significantly enhanced in feeder-freed cells, indicating a feeder cell dependent modulation of lineage differentiation during early embryoid body development. These findings underline the necessity to separate stem and feeder cells before the initiation of in vitro differentiation. The complete separation of stem and feeder cells by this new technology results in pure stem cell populations for translational approaches. Furthermore, a more detailed analysis of the effect of feeder cells on stem cell differentiation is now possible, that might facilitate the identification and development of new optimized human or genetically modified feeder cell lines.

harmonic load modeling: a case study of 33 kv abuja steel mill feeder

African Journals Online (AJOL)

HOD

techniques are adopted. This paper studied the harmonic orders of the 33 kV Abuja Steel Feeder modeled as a ... (ETAP) software package was deployed to perform Discrete Fast Transform (DFT) while the input ... and documented in research and development articles ... network with 33kV Abuja Steel feeder as case study.

The Morris-Lecar neuron model embeds a leaky integrate-and-fire model

DEFF Research Database (Denmark)

Ditlevsen, Susanne; Greenwood, Priscilla

2013-01-01

We showthat the stochastic Morris–Lecar neuron, in a neighborhood of its stable point, can be approximated by a two-dimensional Ornstein Uhlenbeck (OU) modulation of a constant circular motion. The associated radial OU process is an example of a leaky integrate-and-fire (LIF) model prior to firing...

CERN GSM monitoring system

CERN Multimedia

Ghabrous Larrea, C

2009-01-01

As a result of the tremendous development of GSM services over the last years, the number of related services used by organizations has drastically increased. Therefore, monitoring GSM services is becoming a business critical issue in order to be able to react appropriately in case of incident. In order to provide with GSM coverage all the CERN underground facilities, more than 50 km of leaky feeder cable have been deployed. This infrastructure is also used to propagate VHF radio signals for the CERN’s fire brigade. Even though CERN’s mobile operator monitors the network, it cannot guarantee the availability of GSM services, and for sure not VHF services, where signals are carried by the leaky feeder cable. So, a global monitoring system has become critical to CERN. In addition, monitoring this infrastructure will allow to characterize its behaviour over time, especially with LHC operation. Given that commercial solutions were not yet mature, CERN developed a system based on GSM probes and an application...

The effects of single bit quantization on direction of arrival estimation of UHF RFID tags

NARCIS (Netherlands)

Huiting, J.; Kokkeler, Andre B.J.; Smit, Gerardus Johannes Maria

2016-01-01

Phased arrays can be used to estimate the direction-of-arrival (DOA) of UHF RFID tags. To save on energy consumption and hardware costs, in this paper we explore the possibility of using single bit analog-to-digital converters for our phased array setup. This setup consists of an off-the-shelf

Urbanization affects neophilia and risk-taking at bird-feeders

Science.gov (United States)

Tryjanowski, Piotr; Møller, Anders Pape; Morelli, Federico; Biaduń, Waldemar; Brauze, Tomasz; Ciach, Michał; Czechowski, Paweł; Czyż, Stanisław; Dulisz, Beata; Goławski, Artur; Hetmański, Tomasz; Indykiewicz, Piotr; Mitrus, Cezary; Myczko, Łukasz; Nowakowski, Jacek J.; Polakowski, Michał; Takacs, Viktoria; Wysocki, Dariusz; Zduniak, Piotr

2016-06-01

Urban environments cover vast areas with a high density of humans and their dogs and cats causing problems for exploitation of new resources by wild animals. Such resources facilitate colonization by individuals with a high level of neophilia predicting that urban animals should show more neophilia than rural conspecifics. We provided bird-feeders across urban environments in 14 Polish cities and matched nearby rural habitats, testing whether the presence of a novel item (a brightly coloured green object made out of gum with a tuft of hair) differentially delayed arrival at feeders in rural compared to urban habitats. The presence of a novel object reduced the number of great tits Parus major, but also the total number of all species of birds although differentially so in urban compared to rural areas. That was the case independent of the potentially confounding effects of temperature, population density of birds, and the abundance of cats, dogs and pedestrians. The number of great tits and the total number of birds attending feeders increased in urban compared to rural areas independent of local population density of birds. This implies that urban birds have high levels of neophilia allowing them to readily exploit unpredictable resources in urban environments.

A Novel Technology for Motion Capture Using Passive UHF RFID Tags

DEFF Research Database (Denmark)

Krigslund, Rasmus; Popovski, Petar; Pedersen, Gert Frølund

2013-01-01

Although there are several existing methods for human motion capture, they all have important limitations and hence there is the need to explore fundamentally new approaches. Here we present a method based on a Radio Frequency IDentification (RFID) system with passive Ultra High Frequency (UHF...... walking. The reference joint angles for the validation were obtained by an optoelectronic system. Although the method is in its initial phase of development, the results of the validation are promising and show that the movement information can be extracted from the RFID response signals....

Impact of Distribution Feeders that do not have Voltage Regulators on the number of Charged Electric Vehicles using IEEE 34 Bus Test Feeder

Energy Technology Data Exchange (ETDEWEB)

Allehyani, Ahmed [University of Southern California, Department of Electrical Engineering; Beshir, Mohammed [University of Southern California, Department of Electrical Engineering

2015-02-01

Voltage regulators help maintain an acceptable voltage profile for the system. This paper discusses the effect of installing voltage regulators to the system to fix the voltage drop resulting from the electrical vehicles loading increase when they are being charged. The effect will be studied in the afternoon, when the peak load occurs, using the IEEE 34 bus test feeder. First, only one spot node is used to charge the electric vehicles while a voltage regulator is present. Second, five spot nodes are loaded at the same time to charge the electric vehicles while voltage regulators are installed at each node. After that, the impact of electric vehicles on distribution feeders that do not have voltage regulators will appear.

Recent applications of UHF-MRI in the study of human brain function and structure : a review

NARCIS (Netherlands)

Van der Zwaag, W.; Schäfer, Andreas; Marques, José P; Turner, R.; Trampel, Robert

The increased availability of ultra-high-field (UHF) MRI has led to its application in a wide range of neuroimaging studies, which are showing promise in transforming fundamental approaches to human neuroscience. This review presents recent work on structural and functional brain imaging, at 7 T and

Vertical linear feeder to elliptical igneous saucer-shaped sills: evidences from structural observations, geochemistry and experimental modeling

Science.gov (United States)

Galerne, C. Y.; Galland, O.; Neumann, E. R.; Planke, S.

2009-12-01

The structural relationships between sills and their feeders are poorly documented because they are rarely observed in the field and difficult to image on seismic data. For instance, it is unclear whether sills are fed by pipes, dikes or other sills. Nevertheless, the geometrical relationships between sills and their feeders provide first-order constraints on magma emplacement mechanisms. Here, we investigate the structural and geochemical relationships between sills and potential feeder dikes in a remarkably well-preserved and exposed sill complex, the Golden Valley Sill Complex (GVSC), Karoo Basin, South Africa. The GVSC consists of five major saucer-shaped sills and six dikes. The Golden Valley sill itself is an elliptical saucer, with a N-S trend. A one meter thick dike (D4) crops out underneath the southern tip of the Golden Valley sill. The strike of this dike is parallel to the long axis of the Golden Valley sill. Detailed sampling and geochemical analyses of the GVSC show that each sill and dike exhibits a specific geochemical signature. The Golden Valley sill and its underlying dike D4 have identical signatures. Although there is no clear structural evidence, the consistent geometrical and geochemical relationships between the Golden Valley sill and the D4 dike suggest that this vertical linear structure is the feeder of the overlying saucer-shaped sill. In order to investigate the relationships between sills and feeders, we resorted to scaled laboratory experiments. The experiments consisted of a low-viscosity vegetable oil representing magma and a cohesive fine-grained silica flour representing brittle rocks. We placed a horizontal weak layer into the silica flour, just above the top of the inlet, to simulate strata. Such a weak layer controlled the formation of horizontal sill that subsequently turned into a transgressive sheet leading to the formation of a saucer geometry. We ran experiments with varying inlet shapes: 1) a point inlet representing a

Development of I and C system for the coal feeder of coal firing plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Teak Soo; Park, Chan Ho [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1996-12-31

KECC(Kepco Coal Feeder Control System) receives coal weight, conveyor speed and boiler demand signals. It controls coal flow by generating speed signal of feeder which conveys coal in hopper to pulverizer, displaying measured coal quantity and providing local auto and manual manipulator (author). 33 figs.

The Use of Filter-feeders to Manage Disease in a Changing World.

Science.gov (United States)

Burge, Colleen A; Closek, Collin J; Friedman, Carolyn S; Groner, Maya L; Jenkins, Cody M; Shore-Maggio, Amanda; Welsh, Jennifer E

2016-10-01

Rapid environmental change is linked to increases in aquatic disease heightening the need to develop strategies to manage disease. Filter-feeding species are effective biofilters and can naturally mitigate disease risk to humans and wildlife. We review the role of filter-feeders, with an emphasis on bivalves, in altering disease outcomes via augmentation and reduction. Filtration can reduce transmission by removing pathogens from the water column via degradation and release of pathogens in pseudofeces. In other cases, filtration can increase pathogen transmission and disease risk. The effect of filtration on pathogen transmission depends on the selectivity of the filter-feeder, the degree of infectivity by the pathogen, the mechanism(s) of pathogen transmission and the ability of the pathogen to resist degradation. For example, some bacteria and viruses can resist degradation and accumulate within a filter-feeder leading to disease transmission to humans and other wildlife upon ingestion. Since bivalves can concentrate microorganisms, they are also useful as sentinels for the presence of pathogenic microorganisms. While somewhat less studied, other invertebrates, including ascidians and sponges may also provide ecosystem services by altering pathogen transmission. In all scenarios, climate change may affect the potential for filter-feeders to mitigate disease risk. We conclude that an assessment including empirical data and modeling of system-wide impacts should be conducted before selection of filter-feeders to mitigate disease. Such studies should consider physiology of the host and microbe and risk factors for negative impacts including augmentation of other pathogens. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Leaky surface acoustic waves in Z-LiNbO3 substrates with epitaxial AIN overlays

International Nuclear Information System (INIS)

Bu, G.; Ciplys, D.; Shur, M.S.; Namkoong, G.; Doolittle, W.A.; Hunt, W.D.

2004-01-01

The properties of leaky surface acoustic waves (LSAW) in MBE grown AIN layer on Z-cut LiNbO 3 structures have been studied by numerical simulation and experimental measurements and compared with those of Rayleigh waves in the same structure. In the range of AIN layer thicknesses studied (0 3 substrate was essentially constant at around 4400 m/s. The measured electromechanical coupling coefficients (K 2 ) for the LSAW are roughly 1/4 of the predicted values, which might be due to the strong attenuation of the leaky wave unaccounted for during the parameter extraction. The thin AIN film slightly improved the measured temperature coefficient of frequency for the LSAW over that attained for the Z-cut, X-propagating LiNbO 3 substrate alone

High-speed optical feeder-link system using adaptive optics

Science.gov (United States)

Arimoto, Yoshinori; Hayano, Yutaka; Klaus, Werner

1997-05-01

We propose a satellite laser communication system between a ground station and a geostationary satellite, named high- speed optical feeder link system. It is based on the application of (a) high-speed optical devices, which have been developed for ground-based high-speed fiber-optic communications, and (b) the adaptive optics which compensates wavefront distortions due to atmospheric turbulences using a real time feedback control. A link budget study shows that a system with 10-Gbps bit-rate are available assuming the state-of-the-art device performance of the Er-doped fiber amplifier. We further discuss preliminary measurement results of the atmospheric turbulence at the telescope site in Tokyo, and present current study on the design of the key components for the feeder-link laser transceiver.

A hybrid evolutionary algorithm for distribution feeder reconfiguration

Indian Academy of Sciences (India)

the reconfiguration of distribution networks has been proposed by .... An effective strategy to increase the loading margin of heavily loaded feeders is to ... social animals such as a flock of birds, a school of fish or a group of people that pursue.

Digital optical feeder links system for broadband geostationary satellite

Science.gov (United States)

Poulenard, Sylvain; Mège, Alexandre; Fuchs, Christian; Perlot, Nicolas; Riedi, Jerome; Perdigues, Josep

2017-02-01

An optical link based on a multiplex of wavelengths at 1.55μm is foreseen to be a valuable solution for the feeder link of the next generation of high-throughput geostationary satellite. The main satellite operator specifications for such link are an availability of 99.9% over the year, a capacity around 500Gbit/s and to be bent-pipe. Optical ground station networks connected to Terabit/s terrestrial fibers are proposed. The availability of the optical feeder link is simulated over 5 years based on a state-of-the-art cloud mask data bank and an atmospheric turbulence strength model. Yearly and seasonal optical feeder link availabilities are derived and discussed. On-ground and on-board terminals are designed to be compliant with 10Gbit/s per optical channel data rate taking into account adaptive optic systems to mitigate the impact of atmospheric turbulences on single-mode optical fiber receivers. The forward and return transmission chains, concept and implementation, are described. These are based on a digital transparent on-off keying optical link with digitalization of the DVB-S2 and DVB-RCS signals prior to the transmission, and a forward error correcting code. In addition, the satellite architecture is described taking into account optical and radiofrequency payloads as well as their interfaces.

The CERN GSM monitoring system

International Nuclear Information System (INIS)

Ghabrous, Carlos

2010-01-01

This paper presents the way CERN has approached the problem of monitoring its own GSM infrastructure, especially in the Large Hadron Collider (LHC) accelerator tunnel and other underground facilities, where a leaky feeder cable carries mobile phone signals, and where this technology is the only means for inter-personnel communications.

Miniaturized UHF, S-, and Ka-band RF MEMS Filters for Small Form Factor, High Performance EVA Radio, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — In Phase II of this SBIR, Harmonic Devices (HDI) proposes to develop miniaturized MEMS filters at UHF, S-band and Ka-band to address the requirements of NASA's...

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro

OpenAIRE

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-01-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1–5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic ...

Impact of feeder space on laying hen feeding behavior and production performance in enriched colony housing.

Science.gov (United States)

Oliveira, J L; Xin, H; Wu, H

2018-05-30

Current feeder space recommendations in laying hen welfare guidelines are inconsistent among and within countries. One determining criterion forming the recommendations (e.g. 12.0 cm/hen for the EU guideline) is that all birds can feed simultaneously. However, if there are other resources in the environment, as in enriched colony housing (ECH), it is unknown whether group-housed hens will choose to feed simultaneously. This study assesses the impact of feeder space on feeding behavior of 60 laying hens (W-36) in ECH using a ultra-high frequency radio-frequency identification-based tracking system. The feeder spaces investigated were 12.0, 9.5, 8.5 and 6.5 cm/hen, achieved by blocking portions of the overall feeder access to keep hens at the same stocking density. Each feeder space treatment, randomly assigned over the course of the experiment, lasted for 7 consecutive days. Feeding behaviors were characterized as daily time spent at the feeder (TS, min/hen-day), daily frequency of visits to the feeder (FV, #/hen-day), and maximum or average percentage of hens feeding simultaneously (MPB, APB, %). Group-average daily feed intake (FI, g/hen-day), water use (WU, g/hen-day), and hen-day egg production (HDEP, %) were also measured. The results revealed that at 12.0 cm/hen, where unoccupied feeder space was present, a maximum of 59.0±1.4% (average of 31.7±0.3%) hens fed simultaneously. No significant differences were detected among 12.0, 9.5 and 8.5 cm/hen in TS (293±10, 286±10 and 281±10 min/hen-day) and MPB (59.0±1.4, 57.3±1.4 and 53.3±1.4%) (P>0.05). The outcome of no significant differences also held true between 12.0 and 9.5 cm/hen in APB (31.7±0.3 v. 30.8±0.3%) and between 9.5 and 8.5 cm/hen in all response variables measured (P>0.05). However, there were significant differences in APB between 6.5 cm/hen and all other treatments; in TS and FV between 6.5 and 9.5 cm/hen; and in MPB between 6.5 and 12 cm/hen (P0.05). The results revealed that synchronous

Irradiated murine fibroblasts as feeder layer used in human cell culture

International Nuclear Information System (INIS)

Almeida, Tiago L.; Klingbeil, Fatima G.; Yoshito, Daniele; Caproni, Priscila; Mathor, Monica B.; Herson, Marisa R.

2007-01-01

In 1975, Rheinwald and Green published an in vitro model for keratinocyte cell cultures in which the use of murine fibroblasts, as a feeder layer was introduced. These cells are modified fibroblasts, which presence render keratinocyte cells to remain proliferative for longer periods of time. This optimization of culture outputs has allowed for several clinical applications of confluent keratinocyte cultures as skin substitutes or wound dressings in situations such as post burn extensive skin loss, loss of oral mucosa, and other skin disorders. Nevertheless, proliferation of fibroblast in co-culture with keratinocytes must be controlled by anti-proliferative measures such as irradiation; at the same time, keratinocytes require specific nutrients in the culture medium, which may interfere with the fibroblast feeder layer viability. Therefore, the thorough understanding of the impact of different issues such as culture media composition, irradiation dose and pre-plating storage conditions of irradiated fibroblast to be used as feeder layer in these co-culture systems is important. In this work, changes as far as viability and proliferative rates of irradiated fibroblasts in culture were evaluated in relation to the type of culture medium used, dose of gamma radiation exposure, storage and timing of cell plating post irradiation. Results indicate that the type of culture medium used and time-lag between irradiation, refrigeration and plating of irradiated cells do not have significant impact in culture outcomes. However, the dose of gamma radiation administered to the cells may influence the final quality of these cells if to be used as a feeder layer. (author)

Demonstration of Market-Based Real-Time Electricity Pricing on a Congested Feeder

DEFF Research Database (Denmark)

Larsen, Emil Mahler; Pinson, Pierre; le Ray, Guillaume

2015-01-01

Congestion management can delay grid reinforcements needed due to the growth of distributed technologies like photovoltaics and electric vehicles. This paper presents a method of congestion management for low voltage feeders using indirect control from the smart grid demonstration EcoGrid EU, where...... prices to 1900 houses, with a virtual feeder of 28 houses receiving congestion pricing. Simulations are used to calculate the cost from using this congestion management method, while demonstration results indicate that congestion can be managed successfully....

Fabrication of corneal epithelial cell sheets maintaining colony-forming cells without feeder cells by oxygen-controlled method.

Science.gov (United States)

Nakajima, Ryota; Takeda, Shizu

2014-01-01

The use of murine 3T3 feeder cells needs to be avoided when fabricating corneal epithelial cell sheets for use in treating ocular surface diseases. However, the expression level of the epithelial stem/progenitor cell marker, p63, is down-regulated in feeder-free culture systems. In this study, in order to fabricate corneal epithelial cell sheets that maintain colony-forming cells without using any feeder cells, we investigated the use of an oxygen-controlled method that was developed previously to fabricate cell sheets efficiently. Rabbit limbal epithelial cells were cultured under hypoxia (1-10% O2) and under normoxia during stratification after reaching confluence. Multilayered corneal epithelial cell sheets were fabricated using an oxygen-controlled method, and immunofluorescence analysis showed that cytokeratin 3 and p63 was expressed in appropriate localization in the cell sheets. The colony-forming efficiency of the cell sheets fabricated by the oxygen-controlled method without feeder cells was significantly higher than that of cell sheets fabricated under 20% O2 without feeder cells. These results indicate that the oxygen-controlled method has the potential to achieve a feeder-free culture system for fabricating corneal epithelial cell sheets for corneal regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of a feeder device for logging residue for a drum chipper; Hakkurin syoetoen kehittaeminen energiapuulle

Energy Technology Data Exchange (ETDEWEB)

Leinonen, T.; Kemppainen, J P [Oulu Univ. (Finland). Dept. of Mechanical Engineering

1997-12-01

The aim of this project is to increase the productivity of a large drum chipper by developing a feeder device to be used especially when chipping logging residue. Logging residue from regeneration areas is the most important reserve of forest biomass for the production of renewable energy in Finland. It is possible ecologically and economically to use about 5 million m{sup 3} of logging residue yearly for energy purposes. Currently both large lorry based chippers and smaller forwarder based chippers are used for chipping logging residue. However even the latest versions of these chippers are not well equipped for chipping logging residue. The ball like shape of residue piles causes blockades, if too large amounts of residue are fed into the chipper. Keeping the material flow even is difficult. In this project a prototype of a feeder device will be designed and manufactured to exactly find out the problems, that occur when feeding logging residue to a chipper. The designed prototype is based on a tubular chassis, which supports a conveyor made of steel plates. Prototype also has a 2,5 m wide feeding table and a feeder roll, which is located above the conveyor just before the chipper opening. Both the conveyor and the feeder roll are powered by hydraulic motors. The maximum feeding force is 20 kN. For research purposes both hydraulic pressure and flow can be adjusted individually for both motors. During 1996 activities included designing and building the prototype feeder device. In 1997 the prototype will be tested to find out possible problems, which need to be cured. After problems are solved and other improvements are made, the feeder device will be installed to an existing chipper and then tested again to determine the productivity of the new feeder device compared to the old unit. (orig.)

Optimisation of Trap Design for Vibratory Bowl Feeders

DEFF Research Database (Denmark)

Mathiesen, Simon; Sørensen, Lars Carøe; Kraft, Dirk

2018-01-01

Vibratory bowl feeders (VBFs) are a widely used option for industrial part feeding, but their design is still largely manual. A subtask of VBF design is determining an optimal parameter set for the passive devices, called traps, which the VBF uses to ensure correct part orientation. This paper...

Convex relaxation of Optimal Power Flow in Distribution Feeders with embedded solar power

DEFF Research Database (Denmark)

Hermann, Alexander Niels August; Wu, Qiuwei; Huang, Shaojun

2016-01-01

There is an increasing interest in using Distributed Energy Resources (DER) directly coupled to end user distribution feeders. This poses an array of challenges because most of today’s distribution feeders are designed for unidirectional power flow. Therefore when installing DERs such as solar...... panels with uncontrolled inverters, the upper limit of installable capacity is quickly reached in many of today’s distribution feeders. This problem can often be mitigated by optimally controlling the voltage angles of inverters. However, the optimal power flow problem in its standard form is a large...... scale non-convex optimization problem, and thus can’t be solved precisely and also is computationally heavy and intractable for large systems. This paper examines the use of a convex relaxation using Semi-definite programming to optimally control solar power inverters in a distribution grid in order...

Monitoring of biofilm growth using ATR-leaky mode spectroscopy

International Nuclear Information System (INIS)

Leitz, M.; Franke, H.; Grattan, K.T.V.; Tamachkiarow, A.

2002-01-01

An approach to the in situ monitoring of biofilm formation using the technique of ATR-leaky mode spectroscopy is given as an example for the case of Cytophaga. The biofilm growth was studied on an aluminium layer and on a bilayer of the hydrogel agarose on aluminium. This metal was chosen because of its chemical stability in aqueous systems. The spectra obtained have been recorded using a flow cell to contain the suspension and nutrients over a period of several days. In the case considered using a prism surface coated with agarose, the experiments were performed by breeding in an incubator. (author)

Real-Time Distribution Feeder Performance Monitoring, Advisory Control, and Health Management System

Energy Technology Data Exchange (ETDEWEB)

Stoupis, James; Mousavi, Mirrasoul

2014-09-30

New data collection system equipment was installed in Xcel Energy substations and data was collected from 6 substations and 20 feeders. During Phase I, ABB collected and analyzed 793 real-time events to date from 6 Xcel Energy substations and continues today. The development and integration of several applications was completed during the course of this project, including a model-based faulted segment identification algorithm, with very positive results validated with field-gathered data discussed and included in this report. For mostly underground feeders, the success rate is 90% and the overreach rate is 90%. For mostly overhead feeders, the success rate is 74% and the overreach rate is 50%. The developed method is producing very accurate results for mostly underground feeders. For mostly overhead feeders, due to the bad OMS data quality and varying fault resistance when arcing, the developed method is producing good results but with much room for improvement. One area where the algorithm can be improved is the accuracy for sub-cycle fault events. In these cases, the accuracy of the conventional signal processing methods suffers due to most of these methods being based on a one-cycle processing window. By improving the signal processing accuracy, the accuracy of the faulted segment identification algorithm will also improve significantly. ABB intends to devote research in this area in the near future to help solve this problem. Other new applications developed during the course of the project include volt/VAR monitoring, unbalanced capacitor switching detection, unbalanced feeder loading detection, and feeder overloading detection. An important aspect of the demonstration phase of the project is to show the ability to provide adequate “heads-up” time ahead of customer calls or AMI reports so that the operators are provided with the much needed time to collect information needed to address an outage. The advance notification feature of the demonstration system

Isotope study on the Keuper sandstone aquifer with a leaky cover layer

International Nuclear Information System (INIS)

Geyh, M.A.; Backhaus, G.; Andres, G.; Rudolph, J.; Rath, H.K.

1984-01-01

Analyses of 14 C, 3 H, 39 Ar, delta 13 C and delta 18 O were performed on groundwater samples taken from the confined Keuper sandstone aquifer north of Nuremberg. The conventional 14 C data apparently contradict the hydrodynamic concept that the age of the deep groundwater flowing from east to west increases in the same direction. A two-dimensional dispersion model is used to convert the conventional 14 C groundwater ages to the regionally valid hydraulic conductivity coefficient of the leaky cover layer confining the aquifer. The basic assumption is that the deep groundwater has a water component which has percolated through the cover layer and which, on mixing, has changed the 14 C ages of the deep groundwater. Therefore, the ratio of the water from 'leaky' recharge to the water from the catchment area plays an important role. Values of delta 18 O and recharge temperatures derived from the noble-gas content of the deep water indicate mixing of Holocene and Pleistocene groundwaters and confirm the model. The considerable differences between the 39 Ar and 14 C groundwater ages may be plausibly explained by the hydrodynamic situation if 39 Ar production in the aquitard is assumed. (author)

A feeder protection method against the phase-phase fault using symmetrical components

DEFF Research Database (Denmark)

Ciontea, Catalin-Iosif; Bak, Claus Leth; Blaabjerg, Frede

2017-01-01

generation and relatively reduced short-circuit currents, thus resembling the electric network on a ship. The simulation results demonstrate that the proposed method of protection provides an improved performance compared to the conventional OverCurrent relays in a radial feeder with variable short......The method of symmetrical components simplifies analysis of an electric circuit during the fault and represents an important tool for the protection engineers. In this paper, the symmetrical components of the fault current are used in a new feeder protection method for the maritime applications...

Tumorigenic risk of human induced pluripotent stem cell explants cultured on mouse SNL76/7 feeder cells

Energy Technology Data Exchange (ETDEWEB)

Kamada, Mizuna; Mitsui, Youji, E-mail: y-mitsui8310@hb.tp1.jp; Kumazaki, Tsutomu; Kawahara, Yuta; Matsuo, Taira; Takahashi, Tomoko, E-mail: t-takahashi@kph.bunri-u.ac.jp

2014-10-24

Highlights: • hiPS cell explants formed malignant tumors when SNL76/7 feeder cells were used. • Multi type tumors developed by interaction of SNL76/7 feeder cells with hiPS cells. • Tumorigenic risk occurs by co-culture of hiPS cells with SNL76/7 feeder cells. - Abstract: The potential for tumor formation from transplanted human induced pluripotent stem cell (hiPSC) derivatives represents a high risk in their application to regenerative medicine. We examined the genetic origin and characteristics of tumors, that were formed when 13 hiPSC lines, established by ourselves, and 201B7 hiPSC from Kyoto University were transplanted into severe combined immune-deficient (SCID) mice. Though teratomas formed in 58% of mice, five angiosarcomas, one malignant solitary fibrous tumor and one undifferentiated pleomorphic sarcoma formed in the remaining mice. Three malignant cell lines were established from the tumors, which were derived from mitomycin C (MMC)-treated SNL76/7 (MMC-SNL) feeder cells, as tumor development from fusion cells between MMC-SNL and hiPSCs was negative by genetic analysis. While parent SNL76/7 cells produced malignant tumors, neither MMC-SNL nor MMC-treated mouse embryo fibroblast (MEF) produced malignant tumors. When MMC-SNL feeder cells were co-cultured with hiPSCs, growing cell lines were generated, that expressed genes similar to the parent SNL76/7 cells. Thus, hiPSCs grown on MMC-SNL feeder cells have a high risk of generating feeder-derived malignant tumors. The possible mechanism(s) of growth restoration and the formation of multiple tumor types are discussed with respect of the interactions between MMC-SNL and hiPSC.

Tumor Volume Decrease via Feeder Occlusion for Treating a Large, Firm Trigone Meningioma.

Science.gov (United States)

Nakashima, Takuma; Hatano, Norikazu; Kanamori, Fumiaki; Muraoka, Shinsuke; Kawabata, Teppei; Takasu, Syuntaro; Watanabe, Tadashi; Kojima, Takao; Nagatani, Tetsuya; Seki, Yukio

2018-01-01

Trigone meningiomas are considered a surgical challenge, as they tend to be considerably large and hypervascularized at the time of presentation. We experienced a case of a large and very hard trigone meningioma that was effectively treated using initial microsurgical feeder occlusion followed by surgery in stages. A 19-year-old woman who presented with loss of consciousness was referred to our hospital for surgical treatment of a brain tumor. Radiological findings were compatible with a left ventricular trigone meningioma extending laterally in proximity to the Sylvian fissure. At initial surgery using the transsylvian approach, main feeders originating from the anterior and lateral posterior choroidal arteries were occluded at the inferior horn; however, only a small section of the tumor could initially be removed because of its firmness. Over time, feeder occlusion resulted in tumor necrosis and a 20% decrease in its diameter; the mass effect was alleviated within 1 year. The residual meningioma was then totally excised in staged surgical procedures after resection became more feasible owing to ischemia-induced partial softening of the tumor. When a trigone meningioma is large and very hard, initial microsurgical feeder occlusion in the inferior horn can be a safe and effective option, and can lead to necrosis, volume decrease, and partial softening of the residual tumor to allow for its staged surgical excision.

Feeder Cell Type Affects the Growth of In Vitro Cultured Bovine Trophoblast Cells

Directory of Open Access Journals (Sweden)

Islam M. Saadeldin

2017-01-01

Full Text Available Trophectoderm cells are the foremost embryonic cells to differentiate with prospective stem-cell properties. In the current study, we aimed at improving the current approach for trophoblast culture by using granulosa cells as feeders. Porcine granulosa cells (PGCs compared to the conventional mouse embryonic fibroblasts (MEFs were used to grow trophectoderm cells from hatched bovine blastocysts. Isolated trophectoderm cells were monitored and displayed characteristic epithelial/cuboidal morphology. The isolated trophectoderm cells expressed mRNA of homeobox protein (CDX2, cytokeratin-8 (KRT8, and interferon tau (IFNT. The expression level was higher on PGCs compared to MEFs throughout the study. In addition, primary trophectoderm cell colonies grew faster on PGCs, with a doubling time of approximately 48 hrs, compared to MEFs. PGCs feeders produced a fair amount of 17β-estradiol and progesterone. We speculated that the supplementation of sex steroids and still-unknown factors during the trophoblasts coculture on PGCs have helped to have better trophectoderm cell’s growth than on MEFs. This is the first time to use PGCs as feeders to culture trophectoderm cells and it proved superior to MEFs. We propose PGCs as alternative feeders for long-term culture of bovine trophectoderm cells. This model will potentially benefit studies on the early trophoblast and embryonic development in bovines.

Economic Contribution of Regional Feeder Ports to The Local Economy In Indonesia

Directory of Open Access Journals (Sweden)

Ibnu Syabri

2017-07-01

Full Text Available Indonesia regional feeder ports’ main function is to serve marine transport activities between regency/city in a province in limited quantities. The intention of the government to make marine transportation as the backbone of national logistic transportation system puts these ports to an important position, as suppliers for the main and/or collector ports and as goods distribution centers for the region from the bigger ports. Not only as a provider of accessibility between regions, regional feeder ports should be seen as an investation to boost regional economy. This study aims to explain the influences of regional feeder ports on regency/city economy, based on the port types: (1 cargo ports, and (2 cargo & passengers ports. Results showed that both types of ports have positive influences on the regency/city economy, although it is not related to region’s economic base sector. Cargo ports which are mainly located on west area of Indonesia, supports the region’s economy more than cargo & passenger ports which are mainly located on the east.

CPW-Fed Wideband Circular Polarized Antenna for UHF RFID Applications

Directory of Open Access Journals (Sweden)

Sun-Woong Kim

2017-01-01

Full Text Available We propose a wide bandwidth antenna with a circular polarization for universal Ultra High Frequency (UHF radio-frequency identification (RFID reader applications. To achieve a wide 3 dB axial ratio (AR bandwidth, three T-shaped microstrip lines are inserted into the ground plane. The measured impedance bandwidth of the proposed antenna is 480 MHz and extends from 660 to 1080 MHz, and the 3 dB AR bandwidth is 350 MHz and extends from 800 to 1155 MHz. The radiation pattern is a bidirectional pattern with a maximum antenna gain of 3.67 dBi. The overall size of the proposed antenna is 114 × 114 × 0.8 mm3.

Establishment of feeder-free culture system for human induced pluripotent stem cell on DAS nanocrystalline graphene

Science.gov (United States)

Lee, Hyunah; Nam, Donggyu; Choi, Jae-Kyung; Araúzo-Bravo, Marcos J.; Kwon, Soon-Yong; Zaehres, Holm; Lee, Taehee; Park, Chan Young; Kang, Hyun-Wook; Schöler, Hans R.; Kim, Jeong Beom

2016-02-01

The maintenance of undifferentiated human pluripotent stem cells (hPSC) under xeno-free condition requires the use of human feeder cells or extracellular matrix (ECM) coating. However, human-derived sources may cause human pathogen contamination by viral or non-viral agents to the patients. Here we demonstrate feeder-free and xeno-free culture system for hPSC expansion using diffusion assisted synthesis-grown nanocrystalline graphene (DAS-NG), a synthetic non-biological nanomaterial which completely rule out the concern of human pathogen contamination. DAS-NG exhibited advanced biocompatibilities including surface nanoroughness, oxygen containing functional groups and hydrophilicity. hPSC cultured on DAS-NG could maintain pluripotency in vitro and in vivo, and especially cell adhesion-related gene expression profile was comparable to those of cultured on feeders, while hPSC cultured without DAS-NG differentiated spontaneously with high expression of somatic cell-enriched adhesion genes. This feeder-free and xeno-free culture method using DAS-NG will facilitate the generation of clinical-grade hPSC.

The effect of space allowance and cage size on laying hens housed in furnished cages, Part II: Behavior at the feeder.

Science.gov (United States)

Widowski, T M; Caston, L J; Casey-Trott, T M; Hunniford, M E

2017-09-01

Standards for feeder (a.k.a. feed trough) space allowance (SA) are based primarily on studies in conventional cages where laying hens tend to eat simultaneously, limiting feeder space. Large furnished cages (FC) offer more total space and opportunities to perform a greater variety of behaviors, which may affect feeding behavior and feeder space requirements. Our objective was to determine the effects of floor/feeder SA on behavior at the feeder. LSL-Lite hens were housed in FC equipped with a nest, perches, and a scratch mat. Hens with SA of either 520 cm2 (Low; 8.9 cm feeder space/hen) or 748 cm2 (High; 12.8 cm feeder space/hen) per bird resulted in groups of 40 vs. 28 birds in small FC (SFC) and 80 vs. 55 in large FC (LFC). Chain feeders ran at 0500, 0800, 1100, 1400, and 1700 with lights on at 0500 and off at 1900 hours. Digital recordings of FC were scanned at chain feeder onset and every 15 min for one h after (5 scans × 5 feeding times × 2 d) to count the number of birds with their head in the feeder. All occurrences of aggressive pecks and displacements during 2 continuous 30-minute observations at 0800 h and 1700 h also were counted. Mixed model repeated analyses tested the effects of SA, cage size, and time on the percent of hens feeding, and the frequency of aggressive pecks and displacements. Surprisingly, the percent of birds feeding simultaneously was similar regardless of cage size (LFC: 23.0 ± 0.9%; SFC: 24.0 ± 1.0%; P = 0.44) or SA (Low: 23.8 ± 0.9%; High: 23.3 ± 1.0%; P = 0.62). More birds were observed feeding at 1700 h (35.3 ± 0.1%) than any at other time (P Feeder use differed by cage area (nest, middle, or scratch) over the d (P feeder competition at the Low SA in this study. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

Feasibility of graphene CRLH metamaterial waveguides and leaky wave antennas

Energy Technology Data Exchange (ETDEWEB)

Chu, Derrick A.; Itoh, Tatsuo [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Hon, Philip W. C. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); NG NEXT Nanophotonics and Plasmonics Laboratory, Northrop Grumman Aerospace Systems, Redondo Beach, California 90278 (United States); Williams, Benjamin S., E-mail: bswilliams@ucla.edu [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute (CNSI), University of California, Los Angeles, California 90095 (United States)

2016-07-07

The feasibility of composite right/left-handed (CRLH) metamaterial waveguides based upon graphene plasmons is demonstrated via numerical simulation. Designs are presented that operate in the terahertz frequency range along with their various dimensions. Dispersion relations, radiative and free-carrier losses, and free-carrier based tunability are characterized. Finally, the radiative characteristics are evaluated, along with its feasibility for use as a leaky-wave antenna. While CRLH waveguides are feasible in the terahertz range, their ultimate utility will require precise nanofabrication, and excellent quality graphene to mitigate free-carrier losses.

Comparative Method for Indirect Sensitivity Measurement of UHF RFID Reader with Respect to Interoperability and Conformance Requirements

Directory of Open Access Journals (Sweden)

Lukas Kypus

2014-01-01

Full Text Available There is never-ending race for the competitive advantage that forces RFID technology service integrators to focus more on used technology qualitative aspects and theirs impacts inside RFID ecosystem. This paper contributes to UHF RFID reader qualitative parameters evaluation and assessment problematic. It presents and describes in details indirect method and procedure of sensitivity measurement created for UHF RFID readers. We applied this method on RFID readers within prepared test environment and confirmed long term intention and recognized trend. Due to regulations limitations, there is not possible to increase output power over defined limits, but there are possibilities to influence reader sensitivity. Our proposal is to use customized comparative measurement method with insertion loss compensation for return link. Beside the main goal achievement, results show as well the qualitative status of development snapshot of reader. Method and following experiment helped us to gain an external view, current values of important parameters and motivation we want to follow up on as well as compared developed reader with its commercial competitors.

Identification of molecules derived from human fibroblast feeder cells that support the proliferation of human embryonic stem cells

DEFF Research Database (Denmark)

Anisimov, Sergey V.; Christophersen, Nicolaj S.; Correia, Ana S.

2011-01-01

The majority of human embryonic stem cell lines depend on a feeder cell layer for continuous growth in vitro, so that they can remain in an undifferentiated state. Limited knowledge is available concerning the molecular mechanisms that underlie the capacity of feeder cells to support both...... the proliferation and pluripotency of these cells. Importantly, feeder cells generally lose their capacity to support human embryonic stem cell proliferation in vitro following long-term culture. In this study, we performed large-scale gene expression profiles of human foreskin fibroblasts during early...... foreskin fibroblasts to serve as feeder cells for human embryonic stem cell cultures. Among these, the C-KIT, leptin and pigment epithelium-derived factor (PEDF) genes were the most interesting candidates....

Faecal nitrogen of browser and mixed feeder game species during ...

African Journals Online (AJOL)

Faecal nitrogen of browser and mixed feeder game species during different seasons. ... A practical measure of assessing periods of potential nutritional stress of game species is needed in the management of ... AJOL African Journals Online.

A probabilistic degradation model for the estimation of the remaining life distribution of feeders

International Nuclear Information System (INIS)

Yuan, X.-X.; Pandey, M.D.; Bickel, G.A.

2006-01-01

Wall thinning due to flow accelerated corrosion (FAC) is a pervasive form of degradation in the outlet feeder pipes of the primary heat transport system of CANDU reactors. The prediction of the end-of-life of a feeder from wall thickness measurement data is confounded by the sampling and temporal uncertainties associated with the FAC degradation phenomenon. Traditional regression-based statistical methods deal with only the sampling uncertainties, leaving the temporal uncertainties unresolved. This paper presents an advanced probabilistic model, which is able to integrate the temporal uncertainties into the prediction of lifetime. In particular, a random gamma process model is proposed to model the FAC process and it is calibrated with a set of wall thickness measurements using the method of maximum likelihood. This information can be used to establish an optimum strategy for inspection and replacement of feeders. (author)

Feederism: an exaggeration of a normative mate selection preference?

Science.gov (United States)

Terry, Lesley L; Suschinsky, Kelly D; Lalumière, Martin L; Vasey, Paul L

2012-02-01

Quinsey and Lalumière (1995) suggested that some, if not most, paraphilias are exaggerated manifestations of more normative and functional mate selection preferences. The present study tested whether Feederism, a fat fetish focused on erotic eating, feeding, and gaining weight, is an exaggeration of a sexual arousal pattern commonly seen in the general population. Thirty participants (15 men and 15 women) recruited from the general population were assessed using penile plethysmography and vaginal photoplethysmography, respectively. None of the participants were self-identified Feeders or Feedees. Participants were shown sexual, neutral, and feeding still images while listening to audio recordings of sexual, neutral, and feeding stories. Participants did not genitally respond to feeding stimuli. However, both men and women subjectively rated feeding stimuli as more sexually arousing than neutral stimuli. We discuss the discordance between physiological and self-reported sexual arousal in the context of sex differences in sexual concordance and implications for future research.

Experience of superconducting current feeders system of SST-1

International Nuclear Information System (INIS)

Gupta, N.C.; Garg, A.; Sonara, D.

2014-01-01

The superconducting current feeder system for SST-1 which has been installed and commissioned recently along with SST-1, felicitates to energize the SST-1. The CFS consists of ten pairs of 10,000 Ampere (A) rating helium vapor cooled conventional current leads, interconnecting Cu-SC joints, three numbers of cryo-compatible SC feeders ducts, current leads assembly chamber, hydraulic network and three numbers of joint boxes operated at different current rating to charge Toroidal Field and Poloidal Field coils separately. During the last three campaigns, it was possible to achieve a controlled cool down up to 4 K and showed its rated operational performance. Actively cooled liquid nitrogen shield showed temperature profile in the temperature range of 80-85K and the whole system was evacuated up to 6x10 -6 mbar. The measured LHe consumption rates from TF VCCL were 0.3 g/s and 0.35 g/s at zero current and 1 kA respectively. (author)

The effect of space allowance and cage size on laying hens housed in furnished cages, Part II: Behavior at the feeder

Science.gov (United States)

Widowski, T. M; Caston, L. J; Casey-Trott, T. M; Hunniford, M. E

2017-01-01

Abstract Standards for feeder (a.k.a. feed trough) space allowance (SA) are based primarily on studies in conventional cages where laying hens tend to eat simultaneously, limiting feeder space. Large furnished cages (FC) offer more total space and opportunities to perform a greater variety of behaviors, which may affect feeding behavior and feeder space requirements. Our objective was to determine the effects of floor/feeder SA on behavior at the feeder. LSL-Lite hens were housed in FC equipped with a nest, perches, and a scratch mat. Hens with SA of either 520 cm2 (Low; 8.9 cm feeder space/hen) or 748 cm2 (High; 12.8 cm feeder space/hen) per bird resulted in groups of 40 vs. 28 birds in small FC (SFC) and 80 vs. 55 in large FC (LFC). Chain feeders ran at 0500, 0800, 1100, 1400, and 1700 with lights on at 0500 and off at 1900 hours. Digital recordings of FC were scanned at chain feeder onset and every 15 min for one h after (5 scans × 5 feeding times × 2 d) to count the number of birds with their head in the feeder. All occurrences of aggressive pecks and displacements during 2 continuous 30-minute observations at 0800 h and 1700 h also were counted. Mixed model repeated analyses tested the effects of SA, cage size, and time on the percent of hens feeding, and the frequency of aggressive pecks and displacements. Surprisingly, the percent of birds feeding simultaneously was similar regardless of cage size (LFC: 23.0 ± 0.9%; SFC: 24.0 ± 1.0%; P = 0.44) or SA (Low: 23.8 ± 0.9%; High: 23.3 ± 1.0%; P = 0.62). More birds were observed feeding at 1700 h (35.3 ± 0.1%) than any at other time (P < 0.001). Feeder use differed by cage area (nest, middle, or scratch) over the d (P < 0.001). The frequency of aggressive pecks was low overall and not affected by SA or cage size. Frequency of displacements was also low but greater at Low SA (P = 0.001). There was little evidence of feeder competition at the Low SA in this study. PMID:29050409

A fully integrated UHF RFID reader SoC for handheld applications in the 0.18 {mu}m CMOS process

Energy Technology Data Exchange (ETDEWEB)

Wang Jingchao; Zhang Chun; Wang Zhihua, E-mail: wangjc@gmail.co [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

2010-08-15

A low cost fully integrated single-chip UHF radio frequency identification (RFID) reader SoC for short distance handheld applications is presented. The SoC integrates all building blocks-including an RF transceiver, a PLL frequency synthesizer, a digital baseband and an MCU-in a 0.18 {mu}m CMOS process. A high-linearity RX front-end is designed to handle the large self-interferer. A class-E power amplifier with high power efficiency is also integrated to fulfill the function of a UHF passive RFID reader. The measured maximum output power of the transmitter is 20.28 dBm and the measured receiver sensitivity is -60 dBm. The digital baseband including MCU core consumes 3.91 mW with a clock of 10 MHz and the analog part including power amplifier consumes 368.4 mW. The chip has a die area of 5.1 x 3.8 mm{sup 2} including pads. (semiconductor integrated circuits)

A fully integrated UHF RFID reader SoC for handheld applications in the 0.18 μm CMOS process

International Nuclear Information System (INIS)

Wang Jingchao; Zhang Chun; Wang Zhihua

2010-01-01

A low cost fully integrated single-chip UHF radio frequency identification (RFID) reader SoC for short distance handheld applications is presented. The SoC integrates all building blocks-including an RF transceiver, a PLL frequency synthesizer, a digital baseband and an MCU-in a 0.18 μm CMOS process. A high-linearity RX front-end is designed to handle the large self-interferer. A class-E power amplifier with high power efficiency is also integrated to fulfill the function of a UHF passive RFID reader. The measured maximum output power of the transmitter is 20.28 dBm and the measured receiver sensitivity is -60 dBm. The digital baseband including MCU core consumes 3.91 mW with a clock of 10 MHz and the analog part including power amplifier consumes 368.4 mW. The chip has a die area of 5.1 x 3.8 mm 2 including pads. (semiconductor integrated circuits)

The impact of small benthic passive suspension feeders in shallow marine ecosystems: the hydroids as an example

NARCIS (Netherlands)

Gili, J.-M.; Alvà, V.; Coma, R.; Orejas, C.; Pagès, F.; Ribes, M.; Zabala, M.; Arntz, W.; Bouillon, J.; Boero, F.; Hughes, R.G.

1998-01-01

Benthic suspension feeders are abundant in littoral and shallow sub-littoral ecosystems, where they feed on the plankton and on organic matter suspended in the water column. Recent studies indicate that active suspension feeders with powerful water filtration mechanisms (e.g., bivalve molluscs) may

Feeders of Free-Roaming Cats: Personal Characteristics, Feeding Practices, and Data on Cat Health and Welfare in an Urban Setting of Israel.

Science.gov (United States)

Gunther, Idit; Raz, Tal; Even Zor, Yehonatan; Bachowski, Yuval; Klement, Eyal

2016-01-01

Cat feeders serve as an important source of available food for free-roaming cats (FRCs) and can play a central role in providing data on FRC distribution, welfare, and health. Data on cat feeder personalities as well as a better understanding of their feeding practices offer relevance for decision making concerning FRC population control strategies. The current study surveyed 222 FRC feeders who responded to a municipal trap-neuter-return (TNR) campaign in an Israeli central urban setting. The aim of the study was to describe their personal characteristics, feeding practices, and the FRC populations they feed. Feeders were divided into four groups according to the number of cats they claimed to feed per day (group 1: fed up to 5 cats, group 2: fed 6-10 cats, group 3: fed 11-20 cats, and group 4: fed ≥21 cats). Most feeders were women (81%), with a median age of 58 years (range 18-81). The feeders reported an overall feeding of 3337 cats in 342 different feeding locations. Feeders of group 4 comprised 15.31% (n = 34) of all feeders but fed 56% (n = 1869) of the FRC in 37.42% (n = 128) of the feeding locations. "Heavy" feeders (groups 3 and 4) reported that they traveled significantly longer distances in order to feed the cats. Commercial dry food consisted of 90% of the food they provided, with 66% of them feeding once a day, with less food per cat per day than the other feeder groups. Interestingly, "heavy" feeders were usually singles, had on average fewer siblings, a clear preference for owning cats as pets, and lived in lower income neighborhoods. According to the feeders' reports on the FRC populations they fed, 69.7% (2325/3337) cats were neutered and 11.8% (395/3337) were kittens. In addition, they reported that 1.6% (54/3337) of the cats were limping, 2% (67/3337) suffered from a systemic disease, 4% (135/3337) had skin lesions, and 3.9% (130/3337) were suffering from a chronic disability. Abundance of kittens and morbidity rate were

Feeders of free-roaming cats: personal characteristics, feeding practices and data on cat health and welfare in an urban setting of Israel

Directory of Open Access Journals (Sweden)

Idit eGunther

2016-03-01

Full Text Available Cat feeders serve as an important source of available food for free-roaming cats (FRC and can play a central role in providing data on FRC distribution, welfare, and health. Data on cat feeder personalities as well as a better understanding of their feeding practices offer relevance for decision making concerning FRC population control strategies. The current study surveyed 222 FRC feeders who responded to a municipal trap-neuter-return (TNR campaign in an Israeli central urban setting. The aim of the study was to describe their personal characteristics, feeding practices and the FRC populations they feed. Feeders were divided into four groups according to the number of cats they claimed to feed per day (group 1: fed up to five cats; group 2: fed six to 10 cats; group 3: fed 11-20 cats; group 4: fed ≥21 cats. Most feeders were women (81%, with a median age of 58 years (range 18-81. The feeders reported an overall feeding of 3,337 cats in 342 different feeding locations. Feeders of group 4 comprised of 15.31% (n=34 of all feeders, but fed 56% (n=1869 of the FRC in 37.42% (n=128 of the feeding locations. 'Heavy' feeders (groups 3 and 4 reported that they traveled significantly longer distances in order to feed the cats. Commercial dry food consisted of 90% of the food they provided, with 66% of them feeding once a day, with less food per cat per day than the other feeder groups. Interestingly, 'heavy' feeders were usually singles, had on average fewer siblings, a clear preference for owning cats as pets and lived in lower income neighborhoods. According to the feeders' reports on the FRC populations they fed, 69.7% (2325/3337 cats were neutered and 11.8% (395/3337 were kittens. In addition, they reported that 1.6% (54/3337 of the cats were limping, 2% (67/3337 suffered from a systemic disease, 4% (135/3337 had skin lesions, and 3.9% (130/3337 were suffering from a chronic disability. Abundance of kittens and morbidity rate were significantly and

Developmental Competence of Buffalo (Bubalus bubalis) Pluripotent Embryonic Stem Cells Over Different Homologous Feeder Layers and the Comparative Evaluation with Various Extracellular Matrices.

Science.gov (United States)

Sharma, Manjinder; Dubey, Pawan K; Kumar, Rajesh; Nath, Amar; Kumar, G Sai; Sharma, G Taru

2013-05-01

Use of somatic cells as a feeder layer to maintain the embryonic stem cells (ESCs) in undifferentiated state limits the stem cell research design, since experimental data may result from a combined ESCs and feeder cell response to various stimuli. Therefore, present study was designed to evaluate the developmental competence of the buffalo ESCs over different homogenous feeders and compare with various extracellular matrices using different concentrations of LIF. Inner cell masses (ICMs) of in vitro hatched blastocysts were cultured onto homologous feeders viz. fetal fibroblast, granulosa and oviductal cell feeder layers and synthetic matrices viz. fibronectin, collagen type I and matrigel in culture medium. Developmental efficiency was found higher for ESCs cultured on fetal fibroblast and granulosa layers (83.33%) followed by fibronectin (77.78%) at 30 ng LIF. Oviductal feeder was found to be the least efficient feeder showing only 11.11% undifferentiated primary ESC colonies at 30 ng LIF. However, neither feeder layer nor synthetic matrix could support the development of primary colonies at 10 ng LIF. Expression of SSEA- 4, TRA-1-60 and Oct-4 were found positive in ESC colonies from all the feeders and synthetic matrices with 20 ng and 30 ng LIF. Fetal fibroblast and granulosa cell while, amongst synthetic matrices, fibronectin were found to be equally efficient to support the growth and maintenance of ESCs pluripotency with 30 ng LIF. This well-defined culture conditions may provide an animal model for culturing human embryonic stem cells in the xeno-free or feeder-free conditions for future clinical applications.

Meta-analysis on the effects of the physical environment, animal traits, feeder and feed characteristics on the feeding behaviour and performance of growing-finishing pigs.

Science.gov (United States)

Averós, X; Brossard, L; Dourmad, J Y; de Greef, K H; Edwards, S A; Meunier-Salaün, M C

2012-08-01

A meta-analysis, using information from 45 experiments on growing-finishing pigs published in 39 manuscripts, was carried out to determine the simultaneous effects of the physical environment (space allowance, group size, flooring conditions, temperature, presence of enrichment), pig traits (initial body weight (BW) for each studied time interval, sex, genetics), feeder characteristics (water provision within the feeder, feeder design (individual/collective), feeder places/pig, presence of feeder protection) and feed characteristics (feed allowance (ad libitum/restricted), net energy content, crude protein (CP) content), as well as their potential interactions, on the feeding behaviour and performance of growing-finishing pigs. The detrimental effect of low temperature on performance was particularly evident for restricted-fed pigs (P < 0.05). At reduced feeder space allowance, a reduction in the percentage of time spent eating was predicted when increasing initial BW, whereas the opposite was predicted for larger feeder space allowances (P < 0.001). The reduction in visit duration to the feeder in higher BW groups became gradually more important with increasing feeder space allowance (P < 0.01), whereas the increase in the ingestion rate and average daily feed intake (ADFI) with increasing initial BW became smaller with increasing feeder space (P < 0.05). The model predicted a reduction in feed conversion ratio (FCR) with increasing group size (P < 0.05) and floor space allowance (P < 0.01) and on solid floors with or without bedding (P < 0.05). In comparison with other feeders, wet/dry feeders were associated with more frequent but shorter feeder visits (P < 0.05), higher ingestion rates (P < 0.001) and higher ADFI (P < 0.10). The use of protection within individual feeders increased the time spent feeding (P < 0.001), reduced the number of visits per day (P < 0.01), the ingestion rate (P < 0.001) and FCR (P < 0.01) in comparison with other feeder types. Sex

Effect of artificial feeders on pollen loads of the hummingbirds of Cerro de La Muerte, Costa Rica

Directory of Open Access Journals (Sweden)

Gerardo Avalos

2012-03-01

Full Text Available Although sugar-water feeders are commonly used by enthusiasts to attract hummingbirds, little is known about how they affect hummingbird behavior and flower use. We studied the highland hummingbird assemblage of Cerro de La Muerte, Costa Rica, both at a site with permanent feeders (La Georgina Restaurant and further from it. We examined how feeder use and monopolization affected seasonal changes in pollen loads during four sampling periods, including dry and wet seasons, from 2003-2005. We expected that species monopolizing the feeders would carry little or no pollen whatsoever, and would have pollen loads characterized by low floral diversity, in contrast with species less dependent on feeders. We obtained pollen samples from 183 individuals of four hummingbird species captured around the feeders using mist nets, which were compared with a pollen reference collection of plants with a pollination syndrome by hummingbirds. The same methods were implemented at a site 3km away from the feeders. Feeder usage was quantified by counting the number of times hummingbirds drank from the feeders in periods of 4min separated by 1min. The effects of hummingbird species and season on pollen load categories were assessed using a nominal logistic regression. The alpha species at the site, the Fiery-throated Hummingbird (Panterpe insignis, dominated the feeders during the dry season. Meanwhile, in the wet season, feeder usage was more evenly distributed across species, with the exception of the Volcano Hummingbird, Selasphorus flammula, which occupies the last place in the dominance hierarchy. Pollen loads of hummingbirds captured near feeders were low in abundance (more than 50% of captured individuals had zero or low pollen loads, and low in species richness (96% of the hummingbirds with pollen from only one plant genus, Centropogon. Overall pollen loads increased during the dry season coinciding with peaks in flower availability, although the majority of

Effects of wind turbines on UHF television reception: field tests in Denmark

International Nuclear Information System (INIS)

Sorenson, B.

1992-01-01

As a result of a planning application for a windfarm comprising 20 wind turbines at Tynewydd Farm, Gilfach Goch in Mid Glamorgan, a report discussing any detrimental effects the proposal might have on u.h.f. television reception was produced. In order to make the report as definitive as possible, it was decided to carry out field tests on the exact model of wind turbine to be used at Tynewydd. This required a field trip to Denmark, and the opportunity was taken to make measurements on two other models of turbine at the same time. This report presents the analysis of the results for all three turbines. (author)

Letter to the Editor UHF electromagnetic emission stimulated by HF pumping of the ionosphere

Directory of Open Access Journals (Sweden)

S. M. Grach

2002-10-01

Full Text Available UHF electromagnetic emission (with a frequency near 600 MHz from the F-region of the ionosphere pumped by an HF powerful radio wave is revealed. Possible mechanisms of the emission excitation, such as plasma mode con-version, scattering or Earth thermal noise emission off the plasma density irregularities, bremsstrahlung and excitation of high Rydberg states of the neutral particles by the accelerated electrons are discussed.Key words. Ionosphere (active experiments; wave-particle interactions – Solar physics, astrophysics, and astronomy (radio emissions

Letter to the Editor UHF electromagnetic emission stimulated by HF pumping of the ionosphere

Directory of Open Access Journals (Sweden)

E. N. Sergeev

Full Text Available UHF electromagnetic emission (with a frequency near 600 MHz from the F-region of the ionosphere pumped by an HF powerful radio wave is revealed. Possible mechanisms of the emission excitation, such as plasma mode con-version, scattering or Earth thermal noise emission off the plasma density irregularities, bremsstrahlung and excitation of high Rydberg states of the neutral particles by the accelerated electrons are discussed.Key words. Ionosphere (active experiments; wave-particle interactions – Solar physics, astrophysics, and astronomy (radio emissions

[Effects of prefrontal ablations on the reaction of the active choice of feeder under different probability and value of the reinforcement on dog].

Science.gov (United States)

Preobrazhenskaia, L A; Ioffe, M E; Mats, V N

2004-01-01

The role of the prefrontal cortex was investigated on the reaction of the active choice of the two feeders under changes value and probability reinforcement. The experiments were performed on 2 dogs with prefrontal ablation (g. proreus). Before the lesions the dogs were taught to receive food in two different feeders to conditioned stimuli with equally probable alimentary reinforcement. After ablation in the inter-trial intervals the dogs were running from the one feeder to another. In the answer to conditioned stimuli for many times the dogs choose the same feeder. The disturbance of the behavior after some times completely restored. In the experiments with competition of probability events and values of reinforcement the dogs chose the feeder with low-probability but better quality of reinforcement. In the experiments with equal value but different probability the intact dogs chose the feeder with higher probability. In our experiments the dogs with prefrontal lesions chose the each feeder equiprobably. Thus in condition of free behavior one of different functions of the prefrontal cortex is the reactions choose with more probability of reinforcement.

SAR exposure from UHF RFID reader in adult, child, pregnant woman, and fetus anatomical models.

Science.gov (United States)

Fiocchi, Serena; Markakis, Ioannis A; Ravazzani, Paolo; Samaras, Theodoros

2013-09-01

The spread of radio frequency identification (RFID) devices in ubiquitous applications without their simultaneous exposure assessment could give rise to public concerns about their potential adverse health effects. Among the various RFID system categories, the ultra high frequency (UHF) RFID systems have recently started to be widely used in many applications. This study addresses a computational exposure assessment of the electromagnetic radiation generated by a realistic UHF RFID reader, quantifying the exposure levels in different exposure scenarios and subjects (two adults, four children, and two anatomical models of women 7 and 9 months pregnant). The results of the computations are presented in terms of the whole-body and peak spatial specific absorption rate (SAR) averaged over 10 g of tissue to allow comparison with the basic restrictions of the exposure guidelines. The SAR levels in the adults and children were below 0.02 and 0.8 W/kg in whole-body SAR and maximum peak SAR levels, respectively, for all tested positions of the antenna. On the contrary, exposure of pregnant women and fetuses resulted in maximum peak SAR(10 g) values close to the values suggested by the guidelines (2 W/kg) in some of the exposure scenarios with the antenna positioned in front of the abdomen and with a 100% duty cycle and 1 W radiated power. Copyright © 2013 Wiley Periodicals, Inc.

2-D FEM Simulation of Propagation and Radiation of Leaky Lamb Wave in a Plate-Type Ultrasonic Waveguide Sensor

Energy Technology Data Exchange (ETDEWEB)

Park, Sang-Jin; Kim, Hoe-Woong; Joo, Young-Sang; Kim, Sung-Kyun; Kim, Jong-Bum [KAERI, Daejeon (Korea, Republic of)

2016-05-15

This paper introduces the 2-D FEM simulation of the propagation and radiation of the leaky Lamb wave in and from a plate-type ultrasonic waveguide sensor conducted for the radiation beam profile analysis. The FEM simulations are performed with three different excitation frequencies and the radiation beam profiles obtained from FEM simulations are compared with those obtained from corresponding experiments. This paper deals with the 2-D FEM simulation of the propagation and radiation of the leaky Lamb wave in and from a plate-type ultrasonic waveguide sensor conducted to analyze the radiation beam profiles. The radiation beam profile results obtained from the FEM simulation show good agreement with the ones obtained from the experiment. This result will be utilized to improve the performance of the developed waveguide sensor. The quality of the visualized image is mainly affected by beam profile characteristics of the leaky wave radiated from the waveguide sensor. However, the relationships between the radiation beam profile and many parameters of the waveguide sensor are not fully revealed yet. Therefore, further parametric studies are necessary to improve the performance of the sensor and the finite element method (FEM) is one of the most effective tools for the parametric study.

Replacement of murine fibroblasts by human fibroblasts irradiated in obtaining feeder layer for the culture of human keratinocytes

International Nuclear Information System (INIS)

Yoshito, Daniele; Sufi, Bianca S.; Santin, Stefany P.; Mathor, Monica B.; Altran, Silvana C.; Isaac, Cesar

2011-01-01

Human autologous epithelia cultivated in vitro, have been used successfully in treating damage to skin integrity. The methodology allowed the cultivation of these epithelia was described by Rheinwald and Green in 1975, this methodology consisted in seeding keratinocytes onto a feeder layer composed of lineage 3T3 murine fibroblasts, the proliferation rate is controlled through the action of ionizing radiation. However, currently there is a growing concern about the possibility of transmitting prions and murine viruses to transplanted patients. Taking into account this concern, in this present work, we replaced the feeder layer originally composed of murine fibroblasts by human fibroblasts. To obtain this new feeder layer was necessary to standardize the enough irradiation dose to inhibit the replication of human fibroblasts and the verification of effectiveness of the development of keratinocytes culture on a feeder layer thus obtained. According to the obtained results we can verify that the human fibroblasts irradiated at various tested doses (60, 70, 100, 200, 250 and 300 Gy) had their mitotic activity inactivated by irradiation, allowing the use of any of these doses to confection of the feeder layer, since these fibroblasts irradiated still showed viable until fourteen days of cultivation. In the test of colony formation efficiency was observed that keratinocytes seeded on irradiated human fibroblasts were able to develop satisfactorily, preserving their clonogenic potential. Therefore it was possible the replacement of murine fibroblasts by human fibroblasts in confection of the feeder layer, in order to eliminate this xenobiotic component of the keratinocytes culture. (author)

Replacement of murine fibroblasts by human fibroblasts irradiated in obtaining feeder layer for the culture of human keratinocytes

Energy Technology Data Exchange (ETDEWEB)

Yoshito, Daniele; Sufi, Bianca S.; Santin, Stefany P.; Mathor, Monica B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Altran, Silvana C.; Isaac, Cesar [Universidade Sao Paulo (USP), Sao Paulo, SP (Brazil). Fac. de Medicina. Lab. de Microcirurgia Plastica; Esteves-Pedro, Natalia M. [Universidade Sao Paulo (USP), Sao Paulo, SP (Brazil). Fac. de Ciencias Farmaceuticas. Lab. de Controle Biologico; Herson, Marisa R. [DonorTissue Bank of Victoria (Australia)

2011-07-01

Human autologous epithelia cultivated in vitro, have been used successfully in treating damage to skin integrity. The methodology allowed the cultivation of these epithelia was described by Rheinwald and Green in 1975, this methodology consisted in seeding keratinocytes onto a feeder layer composed of lineage 3T3 murine fibroblasts, the proliferation rate is controlled through the action of ionizing radiation. However, currently there is a growing concern about the possibility of transmitting prions and murine viruses to transplanted patients. Taking into account this concern, in this present work, we replaced the feeder layer originally composed of murine fibroblasts by human fibroblasts. To obtain this new feeder layer was necessary to standardize the enough irradiation dose to inhibit the replication of human fibroblasts and the verification of effectiveness of the development of keratinocytes culture on a feeder layer thus obtained. According to the obtained results we can verify that the human fibroblasts irradiated at various tested doses (60, 70, 100, 200, 250 and 300 Gy) had their mitotic activity inactivated by irradiation, allowing the use of any of these doses to confection of the feeder layer, since these fibroblasts irradiated still showed viable until fourteen days of cultivation. In the test of colony formation efficiency was observed that keratinocytes seeded on irradiated human fibroblasts were able to develop satisfactorily, preserving their clonogenic potential. Therefore it was possible the replacement of murine fibroblasts by human fibroblasts in confection of the feeder layer, in order to eliminate this xenobiotic component of the keratinocytes culture. (author)

Directional Emission from Dielectric Leaky-Wave Nanoantennas

Science.gov (United States)

Peter, Manuel; Hildebrandt, Andre; Schlickriede, Christian; Gharib, Kimia; Zentgraf, Thomas; Förstner, Jens; Linden, Stefan

2017-07-01

An important source of innovation in nanophotonics is the idea to scale down known radio wave technologies to the optical regime. One thoroughly investigated example of this approach are metallic nanoantennas which employ plasmonic resonances to couple localized emitters to selected far-field modes. While metals can be treated as perfect conductors in the microwave regime, their response becomes Drude-like at optical frequencies. Thus, plasmonic nanoantennas are inherently lossy. Moreover, their resonant nature requires precise control of the antenna geometry. A promising way to circumvent these problems is the use of broadband nanoantennas made from low-loss dielectric materials. Here, we report on highly directional emission from active dielectric leaky-wave nanoantennas made of Hafnium dioxide. Colloidal semiconductor quantum dots deposited in the nanoantenna feed gap serve as a local light source. The emission patterns of active nanoantennas with different sizes are measured by Fourier imaging. We find for all antenna sizes a highly directional emission, underlining the broadband operation of our design.

Microplastic in a macro filter feeder: humpback whale Megaptera novaeangliae

NARCIS (Netherlands)

Besseling, E.; Foekema, E.M.; Franeker, van J.A.; Leopold, M.F.; Bravo Rebolledo, E.; Kuehn, S.; Mielke, L.; Heberle-Bors, E.; Ijzer, J.; Kamminga, P.; Koelmans, A.A.

2015-01-01

Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water volumes. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in

Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae.

NARCIS (Netherlands)

E., Besseling,; E.M., Foekema,; J.A. van, Franeker; Leopold, Mardik F; Kuhn, S.; Bravo Rebolledo, E.L.; Hese, E.; Mielke, L.; IJzer, J.|info:eu-repo/dai/nl/304839663; Kamminga, P.; Koelmans, A.A.

2015-01-01

Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water volumes. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in

Leaky electronic states for photovoltaic photodetectors based on asymmetric superlattices

Science.gov (United States)

Penello, Germano Maioli; Pereira, Pedro Henrique; Pires, Mauricio Pamplona; Sivco, Deborah; Gmachl, Claire; Souza, Patricia Lustoza

2018-01-01

The concept of leaky electronic states in the continuum is used to achieve room temperature operation of photovoltaic superlattice infrared photodetectors. A structural asymmetric InGaAs/InAlAs potential profile is designed to create states in the continuum with the preferential direction for electron extraction and, consequently, to obtain photovoltaic operation at room temperature. Due to the photovoltaic operation and virtual increase in the bandoffset, the device presents both low dark current and low noise. The Johnson noise limited specific detectivity reaches values as high as 1.4 × 1011 Jones at 80 K. At 300 K, the detectivity obtained is 7.0 × 105 Jones.

A reliable and economical method for gaining mouse embryonic fibroblasts capable of preparing feeder layers.

Science.gov (United States)

Jiang, Guangming; Wan, Xiaoju; Wang, Ming; Zhou, Jianhua; Pan, Jian; Wang, Baolong

2016-08-01

Mouse embryonic fibroblasts (MEFs) are widely used to prepare feeder layers for culturing embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) in vitro. Transportation lesions and exorbitant prices make the commercially obtained MEFs unsuitable for long term research. The aim of present study is to establish a method, which enables researchers to gain MEFs from mice and establish feeder layers by themselves in ordinary laboratories. MEFs were isolated from ICR mouse embryos at 12.5-17.5 day post-coitum (DPC) and cultured in vitro. At P2-P7, the cells were inactivated with mitomycin C or by X-ray irradiation. Then they were used to prepare feeder layers. The key factors of the whole protocol were analyzed to determine the optimal conditions for the method. The results revealed MEFs isolated at 12.5-13.5 DPC, and cultured to P3 were the best choice for feeder preparation, those P2 and P4-P5 MEFs were also suitable for the purpose. The P3-P5 MEFs treated with 10 μg/ml of mitomycin C for 3 h, or irradiated with X-ray at 1.5 Gy/min for 25 Gy were the most suitable feeder cells. Treating MEFs with 10 μg/ml of mitomycin C for 2.5 h, 15 μg/ml for 2.0 h, or irradiating the cells with 20 Gy of X-ray at 2.0 Gy/min could all serve as alternative methods for P3-P4 cells. Our study provides a reliable and economical way to obtain large amount of qualified MEFs for long term research of ESCs or iPSCs.

Utilization of human amniotic mesenchymal cells as feeder layers to sustain propagation of human embryonic stem cells in the undifferentiated state.

Science.gov (United States)

Zhang, Kehua; Cai, Zhe; Li, Yang; Shu, Jun; Pan, Lin; Wan, Fang; Li, Hong; Huang, Xiaojie; He, Chun; Liu, Yanqiu; Cui, Xiaohui; Xu, Yang; Gao, Yan; Wu, Liqun; Cao, Shanxia; Li, Lingsong

2011-08-01

Human embryonic stem (ES) cells are usually maintained in the undifferentiated state by culturing on feeder cells layers of mouse embryonic fibroblasts (MEFs). However, MEFs are not suitable to support human ES cells used for clinical purpose because of risk of zoonosis from animal cells. Therefore, human tissue-based feeder layers need to be developed for human ES cells for clinical purpose. Hereof we report that human amniotic mesenchymal cells (hAMCs) could act as feeder cells for human ES cells, because they are easily obtained and relatively exempt from ethical problem. Like MEFs, hAMCs could act as feeder cells for human ES cells to grow well on. The self-renewal rate of human ES cells cultured on hAMCs feeders was higher than that on MEFs and human amniotic epithelial cells determined by measurement of colonial diameters and growth curve as well as cell cycle analysis. Both immunofluorescence staining and immunoblotting showed that human ES cells cultured on hAMCs expressed stem cell markers such as Oct-3/4, Sox2, and NANOG. Verified by embryoid body formation in vitro and teratoma formation in vivo, we found out that after 20 passages of culture, human ES cells grown on hAMCs feeders could still retain the potency of differentiating into three germ layers. Taken together, our data suggested hAMCs may be safe feeder cells to sustain the propagation of human ES cells in undifferentiated state for future therapeutic use.

Carrying BioMath education in a Leaky Bucket.

Science.gov (United States)

Powell, James A; Kohler, Brynja R; Haefner, James W; Bodily, Janice

2012-09-01

In this paper, we describe a project-based mathematical lab implemented in our Applied Mathematics in Biology course. The Leaky Bucket Lab allows students to parameterize and test Torricelli's law and develop and compare their own alternative models to describe the dynamics of water draining from perforated containers. In the context of this lab students build facility in a variety of applied biomathematical tools and gain confidence in applying these tools in data-driven environments. We survey analytic approaches developed by students to illustrate the creativity this encourages as well as prepare other instructors to scaffold the student learning experience. Pedagogical results based on classroom videography support the notion that the Biology-Applied Math Instructional Model, the teaching framework encompassing the lab, is effective in encouraging and maintaining high-level cognition among students. Research-based pedagogical approaches that support the lab are discussed.

Performance of a Planar Leaky-Wave Slit Antenna for Different Values of Substrate Thickness

Directory of Open Access Journals (Sweden)

Niamat Hussain

2017-10-01

Full Text Available This paper presents the performance of a planar, low-profile, and wide-gain-bandwidth leaky-wave slit antenna in different thickness values of high-permittivity gallium arsenide substrates at terahertz frequencies. The proposed antenna designs consisted of a periodic array of 5 × 5 metallic square patches and a planar feeding structure. The patch array was printed on the top side of the substrate, and the feeding structure, which is an open-ended leaky-wave slot line, was etched on the bottom side of the substrate. The antenna performed as a Fabry-Perot cavity antenna at high thickness levels (H = 160 μm and H = 80 μm, thus exhibiting high gain but a narrow gain bandwidth. At low thickness levels (H = 40 μm and H = 20 μm, it performed as a metasurface antenna and showed wide-gain-bandwidth characteristics with a low gain value. Aside from the advantage of achieving useful characteristics for different antennas by just changing the substrate thickness, the proposed antenna design exhibited a low profile, easy integration into circuit boards, and excellent low-cost mass production suitability.

Low-cost low-power UHF RFID tag with on-chip antenna

Energy Technology Data Exchange (ETDEWEB)

Xi Jingtian; Yan Na; Che Wenyi; Xu Conghui; Wang Xiao; Yang Yuqing; Jian Hongyan; Min Hao, E-mail: jtxi@fudan.edu.c [State Key Laboratory of ASIC and System, Auto-ID Laboratory, Fudan University, Shanghai 201203 (China)

2009-07-15

This paper presents an EPC Class 1 Generation 2 compatible tag with on-chip antenna implemented in the SMIC 0.18 {mu}m standard CMOS process. The UHF tag chip includes an RF/analog front-end, a digital baseband, and a 640-bit EEPROM memory. The on-chip antenna is optimized based on a novel parasitic-aware model. The rectifier is optimized to achieve a power conversion efficiency up to 40% by applying a self-bias feedback and threshold compensation techniques. A good match between the tag circuits and the on-chip antenna is realized by adjusting the rectifier input impedance. Measurements show that the presented tag can achieve a communication range of 1 cm with 1 W reader output power using a 1 x 1 cm{sup 2} single-turn loop reader antenna.

A passive UHF RFID tag with a dynamic-Vth-cancellation rectifier

International Nuclear Information System (INIS)

Shen Jinpeng; Wang Bo; Liu Shan; Wang Xin'an; Ruan Zhengkun; Li Shoucheng

2013-01-01

This paper presents a passive UHF RFID tag with a dynamic-V th -cancellation (DVC) rectifier. In the rectifier, the threshold voltages of MOSFETs are cancelled by applying gate bias voltages, which are dynamically changed according to the states of the MOSFETs. The DVC rectifier enables both low ON-resistance and small reverse leakage of the MOSFETs, resulting in high power conversion efficiency (PCE). An area-efficient demodulator with a novel average detector is also designed, which takes advantage of the rectifier's first stage as the envelope detector. The whole tag chip is implemented in a 0.18 μm CMOS process with a die size of 880 × 950 μm 2 . Measurement results show that the rectifier achieves a maximum PCE of 53.7% with 80 kΩ resistor load. (semiconductor integrated circuits)

Wide-Range Adaptive RF-to-DC Power Converter for UHF RFIDs

KAUST Repository

Ouda, Mahmoud H.

2016-07-27

A wide-range, differential, cross-coupled rectifier is proposed with an extended dynamic range of input RF power that enables wireless powering from varying distances. The proposed architecture mitigates the reverse-leakage problem in conven- tional, cross-coupled rectifiers without degrading sensitivity. A prototype is designed for UHF RFID applications, and is imple- mented using 0.18 μ m CMOS technology. On-chip measurements demonstrate a sensitivity of − 18 dBm for 1 V output over a 100 k Ω load and a peak RF-to-DC power conversion efficiency of 65%. A conventional, fully cross-coupled rectifier is fabricated along- side for comparison and the proposed rectifier shows more than 2 × increase in dynamic range and a 25% boosting in output voltage than the conventional rectifier

Flexible or leaky attention in creative people? Distinct patterns of attention for different types of creative thinking.

Science.gov (United States)

Zabelina, Darya; Saporta, Arielle; Beeman, Mark

2016-04-01

Creativity has been putatively linked to distinct forms of attention, but which aspects of creativity and which components of attention remains unclear. Two experiments examined how divergent thinking and creative achievement relate to visual attention. In both experiments, participants identified target letters (S or H) within hierarchical stimuli (global letters made of local letters), after being cued to either the local or global level. In Experiment 1, participants identified the targets more quickly following valid cues (80% of trials) than following invalid cues. However, this smaller validity effect was associated with higher divergent thinking, suggesting that divergent thinking was related to quicker overcoming of invalid cues, and thus to flexible attention. Creative achievement was unrelated to the validity effect. Experiment 2 examined whether divergent thinking (or creative achievement) is related to "leaky attention," so that when cued to one level of a stimulus, some information is still processed, or leaks in, from the non-cued level. In this case, the cued stimulus level always contained a target, and the non-cued level was congruent, neutral, or incongruent with the target. Divergent thinking did not relate to stimulus congruency. In contrast, high creative achievement was related to quicker responses to the congruent than to the incongruent stimuli, suggesting that real-world creative achievement is indeed associated with leaky attention, whereas standard laboratory tests of divergent thinking are not. Together, these results elucidate distinct patterns of attention for different measures of creativity. Specifically, creative achievers may have leaky attention, as suggested by previous literature, whereas divergent thinkers have selective yet flexible attention.

The Gamma renewal process as an output of the diffusion leaky integrate-and-fire neuronal model

Czech Academy of Sciences Publication Activity Database

Lánský, Petr; Sacerdote, L.; Zucca, C.

2016-01-01

Roč. 110, 2-3 (2016), s. 193-200 ISSN 0340-1200 R&D Projects: GA ČR(CZ) GA15-08066S Institutional support: RVO:67985823 Keywords : first-passage-time problem * leaky integrate-and-fire * Stein's neuronal model Subject RIV: BD - Theory of Information Impact factor: 1.716, year: 2016

Meteor head echo polarization at 930 MHz studied with the EISCAT UHF HPLA radar

Directory of Open Access Journals (Sweden)

G. Wannberg

2011-06-01

Full Text Available The polarization characteristics of 930-MHz meteor head echoes have been studied for the first time, using data obtained in a series of radar measurements carried out with the tristatic EISCAT UHF high power, large aperture (HPLA radar system in October 2009. An analysis of 44 tri-static head echo events shows that the polarization of the echo signal recorded by the Kiruna receiver often fluctuates strongly on time scales of tens of microseconds, illustrating that the scattering process is essentially stochastic. On longer timescales (> milliseconds, more than 90 % of the recorded events show an average polarization signature that is independent of meteor direction of arrival and echo strength and equal to that of an incoherent-scatter return from underdense plasma filling the tristatic observation volume. This shows that the head echo plasma targets scatter isotropically, which in turn implies that they are much smaller than the 33-cm wavelength and close to spherically symmetric, in very good agreement with results from a previous EISCAT UHF study of the head echo RCS/meteor angle-of-incidence relationship. Significant polarization is present in only three events with unique target trajectories. These all show a larger effective target cross section transverse to the trajectory than parallel to it. We propose that the observed polarization may be a signature of a transverse charge separation plasma resonance in the region immediately behind the meteor head, similar to the resonance effects previously discussed in connection with meteor trail echoes by Herlofson, Billam and Browne, Jones and Jones and others.

Investigation of particle reduction and its transport mechanism in UHF-ECR dielectric etching system

International Nuclear Information System (INIS)

Kobayashi, Hiroyuki; Yokogawa, Ken'etsu; Maeda, Kenji; Izawa, Masaru

2008-01-01

Control of particle transport was investigated by using a UHF-ECR etching apparatus with a laser particle monitor. The particles, which float at a plasma-sheath boundary, fall on a wafer when the plasma is turned off. These floating particles can be removed from the region above the wafer by changing the plasma distribution. We measured the distribution of the rotational temperature of nitrogen molecules across the wafer to investigate the effect of the thermophoretic force. We found that mechanisms of particle transport in directions parallel to the wafer surface can be explained by the balance between thermophoretic and gas viscous forces

Towards Washable Electrotextile UHF RFID Tags: Reliability Study of Epoxy-Coated Copper Fabric Antennas

Directory of Open Access Journals (Sweden)

Shiqi Wang

2015-01-01

Full Text Available We investigate the impact of washing on the performance of passive UHF RFID tags based on dipole antennas fabricated from copper fabric and coated with protective epoxy coating. Initially, the tags achieved read ranges of about 8 meters, under the European RFID emission regulation. To assess the impact of washing on the performance of the tags, they were washed repeatedly in a washing machine and measured after every washing cycle. Despite the reliability challenges related to mechanical stress, the used epoxy coating was found to be a promising coating for electrotextile tags in moist conditions.

Scenarios and business models for mobile network operators utilizing the hybrid use concept of the UHF broadcasting spectrum

Directory of Open Access Journals (Sweden)

S. Yrjölä

2016-09-01

Full Text Available This paper explores and presents scenarios and business models for mobile network operators (MNOs in the novel hybrid use spectrum sharing concept of the Ultra High Frequency broadcasting spectrum (470-790 MHz used for Digital Terrestrial TV (DTT and Mobile Broadband (MBB. More flexible use of the band could lead to higher efficiency in delivering fast growing and converging MBB, media and TV content to meet changing consumer needs. On one hand, this could be beneficial for broadcasters (BC, e.g., by preserving the spectrum, by providing additional revenues, or by lowering cost of the spectrum and, on the other hand, for MNOs to gain faster access to new potentially lower cost, licensed, below 1GHz spectrum to cope with booming data traffic. As a collaborative benefit, the concept opens up new business opportunities for delivering TV and media content using MBB network with means to introduce this flexibly. This paper highlights the importance of developing sound business models for the new spectrum use concept, as they need to provide clear benefits to the key stakeholders to be adopted in real life. The paper applies a future and action oriented approach to the MBB using the concept to derive scenarios and business models for MNOs for accessing hybrid UHF bands. In order to address the convergence and transformation coming with the concept, business models are first developed for the current situation with separate exclusive spectrum bands. Novel business scenarios are then developed for the introduction of the new flexible hybrid UHF spectrum concept. The created business model indicates that the MNOs could benefit significantly from the new UHF bands, which would enable them to cope with increasing data traffic asymmetry, and to offer differentiation through personalized broadcasting and new media services. Moreover, it could significantly re-shape the business ecosystem around both the broadcasting and the mobile broadband by introducing

Entropic lattice Boltzmann model for charged leaky dielectric multiphase fluids in electrified jets.

Science.gov (United States)

Lauricella, Marco; Melchionna, Simone; Montessori, Andrea; Pisignano, Dario; Pontrelli, Giuseppe; Succi, Sauro

2018-03-01

We present a lattice Boltzmann model for charged leaky dielectric multiphase fluids in the context of electrified jet simulations, which are of interest for a number of production technologies including electrospinning. The role of nonlinear rheology on the dynamics of electrified jets is considered by exploiting the Carreau model for pseudoplastic fluids. We report exploratory simulations of charged droplets at rest and under a constant electric field, and we provide results for charged jet formation under electrospinning conditions.

Assessing the role of benthic filter feeders on phytoplankton production in a shellfish farming site: Mont Saint Michel Bay, France

Science.gov (United States)

Cugier, Philippe; Struski, Caroline; Blanchard, Michel; Mazurié, Joseph; Pouvreau, Stéphane; Olivier, Frédéric; Trigui, Jihane R.; Thiébaut, Eric

2010-07-01

The macrobenthic community of Mont Saint Michel Bay (English Channel, France) is mainly dominated by filter feeders, including cultivated species (oysters and mussels). An ecological model of the bay was developed, coupling a 2D hydro-sedimentary model and two biological models for primary production and filter-feeder filtration. The filter-feeder model includes three cultivated species ( Mytilus edulis, Crassostrea gigas and Ostrea edulis), one invasive species ( Crepidula fornicata) and eight wild native species ( Abra alba, Cerastoderma edule, Glycymeris glycymeris, Lanice conchilega, Macoma balthica, Paphia rhomboides, Sabellaria alveolata, andSpisula ovalis). For cultivated and invasive species, the production of biodeposits was computed to assess their role in restimulating primary production. Chlorophyll a concentrations appeared to be strongly controlled by the filter feeders. When the pressure of each benthic compartment on phytoplankton was estimated separately wild species and the invasive slipper limpet C.fornicata were shown to be key elements in the control of primary production. Conversely, the role of cultivated species, particularly oysters, was weaker. Feedback due to the mineralization of biodeposits also appears to be crucial to fully evaluate the role of filter feeders in primary production.

Investigating Feasibility Of Multiple UHF Passive RFID Transmitters Using Backscatter Modulation Scheme In BCI Applications

DEFF Research Database (Denmark)

Al Ajrawi, Shams; Sarkar, Mahasweta; Rao, Ramesh

simulatedbrain matter to a receiver located on the surface of a simulatedskull. These analyses are essential for building a brain computerinterface application. We showcase theoretical and experimentalresults based on a phantom model of the human brain usingpassive RFID as the implantable transmitter operating...... in UHFrange. Furthermore, we use backscatter modulation as a powertransfer mechanism. Investigation on the feasibility and appli-cability of implantable UHF Passive RFID transmitters insidethe brain is done for capturing multi-channel ECoG signals at ahigh data transfer rate. Detailed analysis have been done...

Non-leaky modes and bandgaps of surface acoustic waves in wrinkled stiff-film/compliant-substrate bilayers

Science.gov (United States)

Li, Guo-Yang; Xu, Guoqiang; Zheng, Yang; Cao, Yanping

2018-03-01

Surface acoustic wave (SAW) devices have found a wide variety of technical applications, including SAW filters, SAW resonators, microfluidic actuators, biosensors, flow measurement devices, and seismic wave shields. Stretchable/flexible electronic devices, such as sensory skins for robotics, structural health monitors, and wearable communication devices, have received considerable attention across different disciplines. Flexible SAW devices are essential building blocks for these applications, wherein piezoelectric films may need to be integrated with the compliant substrates. When piezoelectric films are much stiffer than soft substrates, SAWs are usually leaky and the devices incorporating them suffer from acoustic losses. In this study, the propagation of SAWs in a wrinkled bilayer system is investigated, and our analysis shows that non-leaky modes can be achieved by engineering stress patterns through surface wrinkles in the system. Our analysis also uncovers intriguing bandgaps (BGs) related to the SAWs in a wrinkled bilayer system; these are caused by periodic deformation patterns, which indicate that diverse wrinkling patterns could be used as metasurfaces for controlling the propagation of SAWs.

Leaky vaccines protect highly exposed recipients at a lower rate: implications for vaccine efficacy estimation and sieve analysis.

Science.gov (United States)

Edlefsen, Paul T

2014-01-01

"Leaky" vaccines are those for which vaccine-induced protection reduces infection rates on a per-exposure basis, as opposed to "all-or-none" vaccines, which reduce infection rates to zero for some fraction of subjects, independent of the number of exposures. Leaky vaccines therefore protect subjects with fewer exposures at a higher effective rate than subjects with more exposures. This simple observation has serious implications for analysis methodologies that rely on the assumption that the vaccine effect is homogeneous across subjects. We argue and show through examples that this heterogeneous vaccine effect leads to a violation of the proportional hazards assumption, to incomparability of infected cases across treatment groups, and to nonindependence of the distributions of the competing failure processes in a competing risks setting. We discuss implications for vaccine efficacy estimation, correlates of protection analysis, and mark-specific efficacy analysis (also known as sieve analysis).

Effect of portion size and milk flow on the use of a milk feeder and the development of cross-sucking in dairy calves

DEFF Research Database (Denmark)

Nielsen, Per Peetz; Jensen, Margit Bak; Halekoh, Ulrich

2018-01-01

milk feeder in each pen, and exposed to four milk-feeding treatments in a cross-over design with four periods of 1 week. All four treatments involved a daily allowance of 8. L of whole milk, with variation in the maximum portion size and the rate at which milk entered the teat of the milk feeder......This study aimed to investigate whether reducing the milk flow and increasing the milk portion size of a computer-controlled milk feeder would lead to less cross-sucking and fewer unrewarded feeder visits in dairy calves. Five groups, each with 9 or 10 calves (n = 48), were housed in pens with one...

Extended post processing for simulation results of FEM synthesized UHF-RFID transponder antennas

Directory of Open Access Journals (Sweden)

R. Herschmann

2007-06-01

Full Text Available The computer aided design process of sophisticated UHF-RFID transponder antennas requires the application of reliable simulation software. This paper describes a Matlab implemented extension of the post processor capabilities of the commercially available three dimensional field simulation programme Ansoft HFSS to compute an accurate solution of the antenna's surface current distribution. The accuracy of the simulated surface currents, which are physically related to the impedance at the feeding point of the antenna, depends on the convergence of the electromagnetic fields inside the simulation volume. The introduced method estimates the overall quality of the simulation results by combining the surface currents with the electromagnetic fields extracted from the field solution of Ansoft HFSS.

Development of two U.H.F. band resonators for application to CO2 laser electro-optical modulation

International Nuclear Information System (INIS)

Egan, M.G.; Blanc, P.; Sexton, M.C.

1980-01-01

The purpose of this report is to describe the design and testing of two U.H.F. band resonators destined for use in the linear electro-optical modulator of the CO 2 Laser Rapid Interferometer diagnostic at present under development for the WEGA Tokamak. The resonators take the form of a re-entrant coaxial line cavity and an interdigital line filter, both of which possess the regions of high electric field necessary to activate the linear electro-optical effect

A General Solution for Groundwater Flow in Estuarine Leaky Aquifer System with Considering Aquifer Anisotropy

Science.gov (United States)

Chen, Po-Chia; Chuang, Mo-Hsiung; Tan, Yih-Chi

2014-05-01

In recent years the urban and industrial developments near the coastal area are rapid and therefore the associated population grows dramatically. More and more water demand for human activities, agriculture irrigation, and aquaculture relies on heavy pumping in coastal area. The decline of groundwater table may result in the problems of seawater intrusion and/or land subsidence. Since the 1950s, numerous studies focused on the effect of tidal fluctuation on the groundwater flow in the coastal area. Many studies concentrated on the developments of one-dimensional (1D) and two-dimensional (2D) analytical solutions describing the tide-induced head fluctuations. For example, Jacob (1950) derived an analytical solution of 1D groundwater flow in a confined aquifer with a boundary condition subject to sinusoidal oscillation. Jiao and Tang (1999) derived a 1D analytical solution of a leaky confined aquifer by considered a constant groundwater head in the overlying unconfined aquifer. Jeng et al. (2002) studied the tidal propagation in a coupled unconfined and confined costal aquifer system. Sun (1997) presented a 2D solution for groundwater response to tidal loading in an estuary. Tang and Jiao (2001) derived a 2D analytical solution in a leaky confined aquifer system near open tidal water. This study aims at developing a general analytical solution describing the head fluctuations in a 2D estuarine aquifer system consisted of an unconfined aquifer, a confined aquifer, and an aquitard between them. Both the confined and unconfined aquifers are considered to be anisotropic. The predicted head fluctuations from this solution will compare with the simulation results from the MODFLOW program. In addition, the solutions mentioned above will be shown to be special cases of the present solution. Some hypothetical cases regarding the head fluctuation in costal aquifers will be made to investigate the dynamic effects of water table fluctuation, hydrogeological conditions, and

Long range ultra-high frequency (UHF) radio frequency identification (RFID) antenna design

Science.gov (United States)

Reynolds, Nathan D.

There is an ever-increasing demand for radio frequency identification (RFID) tags that are passive, long range, and mountable on multiple surfaces. Currently, RFID technology is utilized in numerous applications such as supply chain management, access control, and public transportation. With the combination of sensory systems in recent years, the applications of RFID technology have been extended beyond tracking and identifying. This extension includes applications such as environmental monitoring and healthcare applications. The available sensory systems usually operate in the medium or high frequency bands and have a low read range. However, the range limitations of these systems are being overcome by the development of RFID sensors focused on utilizing tags in the ultra-high frequency (UHF) band. Generally, RFID tags have to be mounted to the object that is being identified. Often the objects requiring identification are metallic. The inherent properties of metallic objects have substantial effects on nearby electromagnetic radiation; therefore, the operation of the tag antenna is affected when mounted on a metallic surface. This outlines one of the most challenging problems for RFID systems today: the optimization of tag antenna performance in a complex environment. In this research, a novel UHF RFID tag antenna, which has a low profile, long range, and is mountable on metallic surfaces, is designed analytically and simulated using a 3-D electromagnetic simulator, ANSYS HFSS. A microstrip patch antenna is selected as the antenna structure, as patch antennas are low profile and suitable for mounting on metallic surfaces. Matching and theoretical models of the microstrip patch antenna are investigated. Once matching and theory of a microstrip patch antenna is thoroughly understood, a unique design technique using electromagnetic band gap (EBG) structures is explored. This research shows that the utilization of an EBG structure in the patch antenna design yields

The effect of stocking density and bin feeder space on performance ...

African Journals Online (AJOL)

The effect of stocking density and bin feeder space on performance in pigs. G.A. Lavers, N.S. Ferguson. Abstract. (South African J of Animal Science, 2000, 30, Supplement 1: 70-71). Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

A Branch-and-Price Approach to the Feeder Network Design Problem

DEFF Research Database (Denmark)

Santini, Alberto; Plum, Christian Edinger Munk; Røpke, Stefan

2017-01-01

In this paper we consider the problem of designing a container liner shipping feeder network. The designer has to choose which port to serve during many rotations that start and end at a central hub. Many operational characteristics are considered, such as variable leg-by-leg speeds and cargo...

Effects of wind turbines on UHF television reception: field tests in Denmark, November 1991

International Nuclear Information System (INIS)

Wright, D.T.

1992-01-01

As a result of a planning application for a wind farm comprising 20 wind turbines at Tynewydd Farm, Gilfach Goch in Mid Glamorgan, it became necessary to produce a Report discussing any detrimental effects the proposal might have on UHF television reception. In order to make that Report as definitive as possible, it was decided to carry out field tests on the exact model of wind turbine to be used to Tynewydd. This required a field trip to Denmark, and the opportunity was taken to make measurements on two other models of turbine at the same time. This Report presents the analysis of the results for all three turbines. (Author)

Study of the coastal atmospheric boundary layer during ESCOMPTE 2001. Evaluation and improvement of the efficiency of a UHF radar; Etude de la couche limite atmospherique cotiere durant ESCOMPTE 2001. Evaluation et amelioration des performances d'un radar UHF

Energy Technology Data Exchange (ETDEWEB)

Puygrenier, V

2005-12-15

Forecasting of pollution events was the main objective of the ESCOMPTE-2001 campaign, which took place in the Marseille/Fos/Berre heterogeneous area (southeastern France) in the early summer 2001. This goal requires good understanding and taking into account, by physico-chemical numerical models, of the physical processes in the Atmospheric Boundary Layer (ABL), in which pollutants are emitted, transported and diffused. In the ESCOMPTE-2001 campaign context, this work was devoted to study the low troposphere during sea breeze events, related to meteorological conditions responsible for poor air quality of coastal areas. It presents notably an oscillation of the sea breeze intensity and competitions of locals and regional sea breeze, which change the advective time of the marine air above the continental surface and thus influence the ABL development and its pollutants concentration. This study is based principally on the network of four UHF wind profilers radars set up on the coastal area of Marseille/Fos/Berre, allowing a continuous three-dimensional description of the sea breeze flow and the ABL. For the needs of this phenomenological work, methodological developments was realized to improve the measurement of ABL turbulent properties with UHF radars (terms of turbulent kinetic energy budget) and the use of wind profilers network for the study of pollutants plumes trajectory-graphy. (author)

Development of ceramic-free antenna feeder

International Nuclear Information System (INIS)

Moriyama, S.; Kimura, H.; Fujii, T.; Saigusa, M.; Arai, H.

1994-01-01

We have proposed a ceramics-free antenna feeder line employing a ridged waveguide as a local support for IC antenna of next-generation tokamaks. One fourth mock-up model of the all metal waveguide designed for the ITER ICRF system is fabricated and electrical characteristics of the model including the coaxial line - waveguide converter are measured. Power reflection coefficient of the model including the coax-waveguide converter to the input coaxial line is estimated to be less than 15% below the cut-off frequency of 107 MHz and less than 3% above the cut-off frequency. It is found that this ceramics-free antenna support employing a ridged waveguide is quite available for IC antenna of next-generation tokamaks. (author)

Design of Two Feeder Three Phase Four Wire Distribution System Utilizing Multi Converter UPQC with Fuzzy Logic Controller

Directory of Open Access Journals (Sweden)

Chandra Babu Paduchuri

2014-01-01

Full Text Available This paper proposes the instantaneous p-q theory based fuzzy logic controller (FLC for multi converter unified power quality conditioner (MC-UPQC to mitigate power quality issues in two feeders three-phase four-wire distribution systems. The proposed system is extended system of the existing one feeder three-phase four-wire distribution system, which is operated with UPQC. This system is employed with three voltage source converters, which are connected commonly to two feeder distribution systems. The performance of this proposed system used to compensate voltage sag, neutral current mitigation and compensation of voltage and current harmonics under linear and nonlinear load conditions. The neutral current flowing in series transformers is zero in the implementation of the proposed system. The simulation performance analysis is carried out using MATLAB.

Evolution of generic supporting conditions for feeders of 500 M We PHWR

International Nuclear Information System (INIS)

Prasad, K.H.; Gupta, K.N.; Bapat, C.N.; Sharma, V.K.; Mishra, R.; Soni, R.S.; Kushwaha, H.S.; Mahajan, S.C.; Kakodkar, A.

1995-01-01

Feeder piping consists of 784 number of closely spaced, inter-connected flexible pipes catering for large thermal and creep movements besides seismic and other loadings. The analytical strategy for evolving generic supporting conditions is outlined in this paper. (author). 4 refs., 7 figs

Interactions among contaminant exposure route, kinetics and toxicity in marine deposit-feeders

DEFF Research Database (Denmark)

Selck, Henriette

Many of the chemicals having the greatest likelihood of causing damage in ecological systems, such as polycyclic aromatic hydrocarbons (PAHs) and metals are of persistent and/or hydrophobic character. Deposit-feeders may be important in facilitating the removal of organic contaminants from bulk...

Selective Mobile Communication within a Coverage Area Bounded by Radiating Cables

Directory of Open Access Journals (Sweden)

Hatim Behairy

2015-01-01

Full Text Available It is often desirable to control mobile phone services in areas where complete silence is either expected or mandatory, including schools, places of worship, hospitals, and prisons. In contrast to conventional techniques, such as jammers or Faraday cages, we present a novel technique to selectively control mobile phone services within a desired area. Our solution enables the area’s keeper to allow mobile phones on a whitelist to freely use mobile services without disruption while denying services to all other mobile phones that are within the boundaries of the desired area to be controlled. Our solution uses a base station controller to identify all mobile devices located within the area to be controlled, while an antenna is placed inside the area to attract all mobile devices in the area to connect to the base station controller. In previous work, we proposed a system that uses directional antennas for the attraction technique. In this work, we show that replacement of the directional antennas with a leaky feeder antenna enables more accurate control of mobile phone services in and around the area to be controlled. Simulations and experiments of the leaky feeder technique confirm its precise control of mobile phone services within the desired areas.

A HYBRID APPROACH FOR RURAL FEEDER DESIGN

Directory of Open Access Journals (Sweden)

DAMANJEET KAUR

2012-08-01

Full Text Available In this paper, a population based approach for conductor size selection in rural radial distribution system is presented. The proposed hybrid approach implies a particle swarm optimization (PSO approach in combination with mutant property of differential evolution (DE for conductor size selection in radial distribution system. The conductor size for each feeder segment is selected such that the total cost of capital investment and capitalized cost of energy losses is minimized while constraints of voltage at each node and current carrying capacity of conductor is within the limits. The applicability and effectiveness of the proposed method is demonstrated with the help of 32-node test system.

The effect of stocking density and bin feeder space on performance ...

African Journals Online (AJOL)

Unknown

The effect of stocking density and bin feeder space on performance in pigs. G.A. Lavers# and N.S. Ferguson. School of Agricultural Sciences & Agribusiness, University of Natal, P Bag X01, Scottsville 3209. #Email: lavers@agric.unp.ac.za. Introduction. Pigs housed individually have been shown to have higher feed intakes ...

A two-dimensional analytical model for groundwater flow in a leaky aquifer extending finite distance under the estuary

Science.gov (United States)

Chuang, Mo-Hsiung; Hung, Chi-Tung; -Yen Lin, Wen; Ma, Kuo-chen

2017-04-01

In recent years, cities and industries in the vicinity of the estuarine region have developed rapidly, resulting in a sharp increase in the population concerned. The increasing demand for human activities, agriculture irrigation, and aquaculture relies on massive pumping of water in estuarine area. Since the 1950s, numerous studies have focused on the effects of tidal fluctuations on groundwater flow in the estuarine area. Tide-induced head fluctuation in a two-dimensional estuarine aquifer system is complicated and rather important in dealing with many groundwater management or remediation problems. The conceptual model of the aquifer system considered is multi-layered with estuarine bank and the leaky aquifer extend finite distance under the estuary. The solution of the model describing the groundwater head distribution in such an estuarine aquifer system and subject to the tidal fluctuation effects from estuarine river is developed based on the method of separation of variables along with river boundary. The solutions by Sun (Sun H. A two-dimensional analytical solution of groundwater response to tidal loading in an estuary, Water Resour. Res. 1997; 33:1429-35) as well as Tang and Jiao (Tang Z. and J. J. Jiao, A two-dimensional analytical solution for groundwater flow in a leaky confined aquifer system near open tidal water, Hydrological Processes, 2001; 15: 573-585) can be shown to be special cases of the present solution. On the basis of the analytical solution, the groundwater head distribution in response to estuarine boundary is examined and the influences of leakage, hydraulic parameters, and loading effect on the groundwater head fluctuation due to tide are investigated and discussed. KEYWORDS: analytical model, estuarine river, groundwater fluctuation, leaky aquifer.

Design of an ultra-low-power digital processor for passive UHF RFID tags

Energy Technology Data Exchange (ETDEWEB)

Shi Wanggen; Zhuang Yiqi; Li Xiaoming; Wang Xianghua; Jin Zhao; Wang Dan, E-mail: wanggen_shi@163.co [Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, Institute of Microelectronics, Xidian University, Xi' an 710071 (China)

2009-04-15

A new architecture of digital processors for passive UHF radio-frequency identification tags is proposed. This architecture is based on ISO/IEC 18000-6C and targeted at ultra-low power consumption. By applying methods like system-level power management, global clock gating and low voltage implementation, the total power of the design is reduced to a few microwatts. In addition, an innovative way for the design of a true RNG is presented, which contributes to both low power and secure data transaction. The digital processor is verified by an integrated FPGA platform and implemented by the Synopsys design kit for ASIC flows. The design fits different CMOS technologies and has been taped out using the 2P4M 0.35 mum process of Chartered Semiconductor.

Microalbuminuria reflects a generalized transvascular albumin leakiness in clinically healthy subjects

DEFF Research Database (Denmark)

Jensen, J S; Borch-Johnsen, K; Jensen, G

1995-01-01

1. In epidemiological studies microalbuminuria, i.e. slightly elevated urinary albumin excretion rate, predicts increased atherosclerotic vascular morbidity and mortality. This study aimed to test the hypothesis that microalbuminuria in clinically healthy subjects is associated with a systemic...... transvascular albumin leakiness. In animal experiments the outflux of albumin and lipids to the arterial wall are highly correlated, and both are elevated in atherosclerosis. 2. All participants were recruited at random from a population-based epidemiological study, where the upper decile of urinary albumin...... excretion rate was 6.6 micrograms/min. Twenty-seven patients with persistent microalbuminuria (urinary albumin excretion rate 6.6-150 micrograms/min), and 56 age- and sex-matched control subjects with persistent normoalbuminuria (UAER

Development of expanded type plugging technique for leaky tubes of steam generators of Indian PHWRs

International Nuclear Information System (INIS)

Das, Nirupam; Samuel, K.A.; Joemon, V.; Rupani, B.B.

2006-01-01

Steam generators are very important component of Nuclear Power Plant (NPP), as they are part of Primary Heat Transport (PHT) system of Pressurised Heavy Water Reactors (PHWRs). A nuclear power plant of 220 MWe capacity has four mushroom type steam generators, each consisting of 1830 U-tubes (16 mm outside diameter and 1 mm wall thickness) made of Incoloy-800 material. The tubes of 'tube and shell type steam generator' act as the pressure boundary of PHT System. Any structural failure of these tubes may lead to release of radioactivity along with plant outage and significant economic loss. Hence, it is necessary to plug the leaky tubes for continued and safe operation of a steam generator. An expanded type plugging technique has been developed at Reactor Engineering Division to plug the leaky tubes. This plugging technique is selected because of low residual stress imparted in the adjacent 'tube to tube-sheet' joints. This plug meets the various codal requirements of steam generator. A number of qualification trials have been carried out with such plugs in the mock up facility. The expanded plugs meet the design requirements for pull out strength and leak-tightness. This paper describes the design concept of the plug, developmental aspects and qualification of the plugging technique. (author)

Study of the coastal atmospheric boundary layer during ESCOMPTE 2001. Evaluation and improvement of the efficiency of a UHF radar; Etude de la couche limite atmospherique cotiere durant ESCOMPTE 2001. Evaluation et amelioration des performances d'un radar UHF

Energy Technology Data Exchange (ETDEWEB)

Puygrenier, V.

2005-12-15

Forecasting of pollution events was the main objective of the ESCOMPTE-2001 campaign, which took place in the Marseille/Fos/Berre heterogeneous area (southeastern France) in the early summer 2001. This goal requires good understanding and taking into account, by physico-chemical numerical models, of the physical processes in the Atmospheric Boundary Layer (ABL), in which pollutants are emitted, transported and diffused. In the ESCOMPTE-2001 campaign context, this work was devoted to study the low troposphere during sea breeze events, related to meteorological conditions responsible for poor air quality of coastal areas. It presents notably an oscillation of the sea breeze intensity and competitions of locals and regional sea breeze, which change the advective time of the marine air above the continental surface and thus influence the ABL development and its pollutants concentration. This study is based principally on the network of four UHF wind profilers radars set up on the coastal area of Marseille/Fos/Berre, allowing a continuous three-dimensional description of the sea breeze flow and the ABL. For the needs of this phenomenological work, methodological developments was realized to improve the measurement of ABL turbulent properties with UHF radars (terms of turbulent kinetic energy budget) and the use of wind profilers network for the study of pollutants plumes trajectory-graphy. (author)

Conditions for the spectrum associated with an asymptotically straight leaky wire to comprise the interval (-∞, ∞)

International Nuclear Information System (INIS)

Brown, B M; Eastham, M S P; Wood, I G

2009-01-01

We consider a quantum (or leaky) wire in the plane, and the wire supports a singular attraction which becomes large at distant points on the wire. An analogous regular potential arises from the motion of a hydrogen atom in an electric field. We prove that, as in the regular case, the spectrum is the whole of (-∞, ∞)

Conditions for the spectrum associated with an asymptotically straight leaky wire to comprise the interval (-{infinity}, {infinity})

Energy Technology Data Exchange (ETDEWEB)

Brown, B M; Eastham, M S P [Department of Computer Science, Cardiff University, Cardiff, CF24 3XF (United Kingdom); Wood, I G [Institute of Mathematics and Physics, Aberystwyth University, Penglais, Aberystwyth, Ceredigion, SY23 3BZ (United Kingdom)], E-mail: malcolm@cs.cf.ac.uk, E-mail: mandh@chesilhay.fsnet.co.uk, E-mail: iww@aber.ac.uk

2009-02-06

We consider a quantum (or leaky) wire in the plane, and the wire supports a singular attraction which becomes large at distant points on the wire. An analogous regular potential arises from the motion of a hydrogen atom in an electric field. We prove that, as in the regular case, the spectrum is the whole of (-{infinity}, {infinity})

Urban and rural habitats differ in number and type of bird feeders and in bird species consuming supplementary food.

Science.gov (United States)

Tryjanowski, Piotr; Skórka, Piotr; Sparks, Tim H; Biaduń, Waldemar; Brauze, Tomasz; Hetmański, Tomasz; Martyka, Rafał; Indykiewicz, Piotr; Myczko, Łukasz; Kunysz, Przemysław; Kawa, Piotr; Czyż, Stanisław; Czechowski, Paweł; Polakowski, Michał; Zduniak, Piotr; Jerzak, Leszek; Janiszewski, Tomasz; Goławski, Artur; Duduś, Leszek; Nowakowski, Jacek J; Wuczyński, Andrzej; Wysocki, Dariusz

2015-10-01

Bird feeding is one of the most widespread direct interactions between man and nature, and this has important social and environmental consequences. However, this activity can differ between rural and urban habitats, due to inter alia habitat structure, human behaviour and the composition of wintering bird communities. We counted birds in 156 squares (0.25 km(2) each) in December 2012 and again in January 2013 in locations in and around 26 towns and cities across Poland (in each urban area, we surveyed 3 squares and also 3 squares in nearby rural areas). At each count, we noted the number of bird feeders, the number of bird feeders with food, the type of feeders, additional food supplies potentially available for birds (bread offered by people, bins) and finally the birds themselves. In winter, urban and rural areas differ in the availability of food offered intentionally and unintentionally to birds by humans. Both types of food availability are higher in urban areas. Our findings suggest that different types of bird feeder support only those species specialized for that particular food type and this relationship is similar in urban and rural areas.

Changes in food intake and abnormal behavior using a puzzle feeder in newly acquired sub-adult rhesus monkeys (Macaca mulatta): a short term study.

Science.gov (United States)

Lee, Jae-Il; Lee, Chi-Woo; Kwon, Hyouk-Sang; Kim, Young-Tae; Park, Chung-Gyu; Kim, Sang-Joon; Kang, Byeong-Cheol

2008-10-01

The majority of newly acquired nonhuman primates encounter serious problems adapting themselves to new environments or facilities. In particular, loss of appetite and abnormal behavior can occur in response to environmental stresses. These adaptation abnormalities can ultimately have an affect on the animal's growth and well-being. In this study, we evaluated the affects of a puzzle feeder on the food intake and abnormal behavior of newly acquired rhesus monkeys for a short period. The puzzle feeder was applied to 47- to 58-month-old animals that had never previously encountered one. We found that there was no difference in the change of food intake between the bucket condition and the puzzle feeder condition. In contrast, the time spent for consumption of food was three times longer in the puzzle feeder condition than in the bucket condition. Two monkeys initially exhibited stereotypic behavior. One showed a decreasing, and the other an increasing pattern of abnormal behavior after introduction of the puzzle feeder. In conclusion, this result suggests that over a short period, the puzzle feeder can only affect the time for food consumption since it failed to affect the food intake and did not consistently influence stereotypic behaviors in newly acquired rhesus monkeys.

Resolving the architecture of monogenetic feeder systems from exposures of extinct volcanic fields

Science.gov (United States)

Muirhead, J.; Van Eaton, A. R.; Re, G.; White, J. D. L.; Ort, M. H.

2016-12-01

Monogenetic volcanic fields pose hazards to a number of major cities worldwide. During an eruption, the evolution of the intrusive feeder network modulates eruption behavior and location, as well as the warning signs of impending activity. However, historical examples of monogenetic eruptions are rare, particularly those monitored with the modern tools required to constrain the geometry and interconnectivity of subsurface intrusive feeders (e.g., InSAR, GPS). Geologic exposures in extinct fields around the Colorado Plateau provide clues to the geometry of shallow intrusions (<1000 m depth) that feed monogenetic volcanoes. We present field- and satellite-based observations of exposed intrusions in the Hopi Buttes volcanic field (Arizona), which reveal that many eruptions were fed by interconnected dike-sill systems. Results from the Hopi Buttes show that volcanic cone alignment studies are biased to the identification of dike intrusions, and thereby neglect the important contributions of sills to shallow feeder systems. For example, estimates of intruded volumes in fields exhumed by uplift and erosion in Utah and Arizona show that sills make up 30 - 92% of the shallow intruded volume within 1000 m of the paleosurface. By transporting magma toward and away from eruptive conduits, these sills likely played a role in modulating eruption styles (e.g., explosive vs effusive) and controlling lateral vent migrations. Sill transitions at Hopi Buttes would have produced detectable surface uplifts, and illustrate the importance of geological studies for informing interpretations of geodetic and seismological data during volcanic crises.

Photovoltaic Hosting Capacity of Feeders with Reactive Power Control and Tap Changers

Energy Technology Data Exchange (ETDEWEB)

Ceylan, Oğuzhan; Paudyal, Sumit; Bhattarai, Bishnu P.; Myers, Kurt S.

2017-06-01

This paper proposes an algorithm to determine photovoltaic (PV) hosting capacity of power distribution networks as a function of number of PV injection nodes, reactive power support from the PVs, and the sub-station load tap changers (LTCs). In the proposed method, several minute by minute simulations are run based on randomly chosen PV injection nodes, daily PV output profiles, and daily load profiles from a pool of high-resolution realistic data set. The simulation setup is built using OpenDSS and MATLAB. The performance of the proposed method is investigated in the IEEE 123-node distribution feeder for multiple scenarios. The case studies are performed particularly for one, two, five and ten PV injection nodes, and looking at the maximum voltage deviations. Case studies show that the PV hosting capacity of the 123-node feeder greatly differs with the number of PV injection nodes. We have also observed that the PV hosting capacity increases with reactive power support and higher tap position of sub-station LTC.

The effects of automated scatter feeders on captive grizzly bear activity budgets.

Science.gov (United States)

Andrews, Nathan L P; Ha, James C

2014-01-01

Although captive bears are popular zoo attractions, they are known to exhibit high levels of repetitive behaviors (RBs). These behaviors have also made them particularly popular subjects for welfare research. To date, most research on ursid welfare has focused on various feeding methods that seek to increase time spent searching for, extracting, or consuming food. Prior research indicates an average of a 50% reduction in RBs when attempts are successful and, roughly, a 50% success rate across studies. This research focused on decreasing time spent in an RB while increasing the time spent active by increasing time spent searching for, extracting, and consuming food. The utility of timed, automated scatter feeders was examined for use with captive grizzly bears (Ursis arctos horribilis). Findings include a significant decrease in time spent in RB and a significant increase in time spent active while the feeders were in use. Further, the bears exhibited a wider range of behaviors and a greater use of their enclosure.

harmonic load modeling: a case study of 33 kv abuja steel mill feeder

African Journals Online (AJOL)

HOD

An in-depth study of the harmonic orders inherent in a power system network is required ... This paper studied the harmonic orders of the 33 kV Abuja Steel Feeder .... models for various industrial and household electrical ..... Malaysia, 2013.

Cone-Beam Computed Tomography (CBCT) Hepatic Arteriography in Chemoembolization for Hepatocellular Carcinoma: Performance Depicting Tumors and Tumor Feeders

Energy Technology Data Exchange (ETDEWEB)

Lee, In Joon [National Cancer Center, Department of Radiology (Korea, Republic of); Chung, Jin Wook, E-mail: chungjw@snu.ac.kr; Yin, Yong Hu; Kim, Hyo-Cheol; Kim, Young Il; Jae, Hwan Jun; Park, Jae Hyung [Seoul National University College of Medicine, Seoul National University Hospital, Department of Radiology (Korea, Republic of)

2015-10-15

PurposeThis study was designed to analyze retrospectively the performance of cone-beam computed tomography (CBCT) hepatic arteriography in depicting tumors and their feeders and to investigate the related determining factors in chemoembolization for hepatocellular carcinoma (HCC).MethodsEighty-six patients with 142 tumors satisfying the imaging diagnosis criteria of HCC were included in this study. The performance of CBCT hepatic arteriography for chemoembolization per tumor and per patient was evaluated using maximum intensity projection images alone (MIP analysis) or MIP combined with multiplanar reformation images (MIP + MPR analysis) regarding the following three aspects: tumor depiction, confidence of tumor feeder detection, and trackability of tumor feeders. Tumor size, tumor enhancement, tumor location, number of feeders, diaphragmatic motion, portal vein enhancement, and hepatic artery to parenchyma enhancement ratio were regarded as potential determining factors.ResultsTumors were depicted in 125 (88.0 %) and 142 tumors (100 %) on MIP and MIP + MPR analysis, respectively. Imaging performances on MIP and MIP + MPR analysis were good enough to perform subsegmental chemoembolization without additional angiographic investigation in 88 (62.0 %) and 128 tumors (90.1 %) on per-tumor basis and in 43 (50 %) and 73 (84.9 %) on per-patient basis, respectively. Significant determining factors for performance in MIP + MPR analysis on per tumor basis were tumor size (p = 0.030), tumor enhancement (0.005), tumor location (p = 0.001), and diaphragmatic motion (p < 0.001).ConclusionsCBCT hepatic arteriography provided sufficient information for subsegmental chemoembolization by depicting tumors and their feeders in the vast majority of patients. Combined analysis of MIP and MPR images was essential to enhance the performance of CBCT hepatic arteriography.

Flow visualization study of two-phase flow in a single bend outlet feeder pipe of a CANDU reactor

International Nuclear Information System (INIS)

Savalaxs, S.-A.; Lister, D.H.; Steward, F.R.

2005-01-01

In CANDU reactors, the feeder piping that is used to direct the high-temperature water coolant between the fuel channels and the steam generators is made of carbon steel. Since 1996, several CANDU stations have reported excessive corrosion of their outlet feeders. The first metre is particularity vulnerable because the piping there consists of single or double bends, which have relatively thin walls produced by the bending process. Early studies related the attack to the hydrodynamics of the coolant and verified that it was a type of flow-accelerated corrosion. In order to understand the hydrodynamics of the coolant in the outlet feeders by flow visualization, a full-scale transparent test section simulating the geometry and orientation of an outlet feeder bend with its upstream components was fabricated. The feeder consisted of a 54 mm diameter acrylic pipe with a 73 degree bend. This was connected to the upstream component with an acrylic simulation of a Grayloc flanged fitting. A test loop supplied room temperature water to the test section at flow rates up to 0.019 m3/s. Air could be injected into the water to give a mean volume fraction of up to 0.56. In this preliminary investigation, the size and velocity of air bubbles at different flow conditions and their distribution within the pipe bend were studied. Particular attention was paid to the flow pattern at the inside of the bend, where a CFD (computational fluid dynamics) code - Fluent 6.1-had failed to predict a liquid film in an earlier study. A high-speed digital video camera was used to determine the relation between bubble size and velocity. Such a relation should help to explain the discrepancy in the CFD modelling and provide the basis for accurate predictions of phase distribution in complex geometries at high flow rates. (authors)

Optimalisatie performance van vleeskuikens bij mobiel voer- en drinksysteem (scanFeeder) op praktijkbedrijf

NARCIS (Netherlands)

Harn, van J.; Veldkamp, T.

2007-01-01

Het gebruik van de Ridder ScanFeeder, een mobiel voer- en drinksysteem met strooiselbeluchting voor vleeskuikens, geeft een betere strooiselkwaliteit (ruller en droger strooisel) en minder voetzoolaandoeningen. De technische resultaten bij dit systeem blijven echter achter bij die van een

Communication with extraterrestrial intelligences - Possibilities, chances, and perspectives with special attention given to the leaky-embargo hypothesis

Science.gov (United States)

Fiebag, Johannes

1989-12-01

Present SETI projects are described, emphasizing search methods alternative to investigations in the radio range. The possibility that the human race is being studied by alien presences within the solar system is addressed in the context of the 'zoo hypothesis' and the 'leaky embargo' hypothesis. In the former, the aliens prevent any contact with humans, while in the latter occasional contact is permitted.

Manufacture and test of prototype water pipe chase barrier in ITER Magnet Feeder system

Energy Technology Data Exchange (ETDEWEB)

Lu, Kun, E-mail: lukun@ipp.ac.cn [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Wen, Xinjie; Liu, Chen; Song, Yuntao [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Niu, Erwu [ITER China, 15B Fuxing Road, Beijing 100862 (China); Gung, Chenyu; Su, Man [ITER Organization, Route de Vinon-sur-Verdon – CS 90046, 13067 St Paul-lez-Durance Cedex (France)

2016-11-01

The Magnet Feeder system in the International Thermonuclear Experimental Reactor (ITER) deploys electrical currents and supercritical helium to the superconducting magnets and the magnet diagnostic signals to the operators. In the current design, the feeders located in the upper L3 level of the Tokamak gallery penetrate the Tokamak coolant water system vault, the biological shield and the cryostat. As a secondary confinement to contain the activated coolant water in the vault in the case of water pipe burst accident, a water barrier is welded between the penetration in the water pipe chase outer wall and the mid-plane of the vacuum jacket of the Feeder Coil Terminal Box (CTB). A thin-wall stainless steel diaphragm with an omega shape profile is welded around the CTB as the water barrier to endure 2 bar hydraulic pressure. In addition, the barrier is designed as a flexible compensator to withstand a maximum of 15 mm of axial displacement of the CTB in case of helium leak accident without failure. This paper presents the detail configuration, the manufacturing and assembly processes of the water barrier. Test results of the prototype water barrier under simulated accident conditions are also reported. Successful qualification of the design and manufacturing process of the water barrier lays a good foundation for the series production of this subsystem.

Design of an ultra-low-power digital processor for passive UHF RFID tags

International Nuclear Information System (INIS)

Shi Wanggen; Zhuang Yiqi; Li Xiaoming; Wang Xianghua; Jin Zhao; Wang Dan

2009-01-01

A new architecture of digital processors for passive UHF radio-frequency identification tags is proposed. This architecture is based on ISO/IEC 18000-6C and targeted at ultra-low power consumption. By applying methods like system-level power management, global clock gating and low voltage implementation, the total power of the design is reduced to a few microwatts. In addition, an innovative way for the design of a true RNG is presented, which contributes to both low power and secure data transaction. The digital processor is verified by an integrated FPGA platform and implemented by the Synopsys design kit for ASIC flows. The design fits different CMOS technologies and has been taped out using the 2P4M 0.35 μm process of Chartered Semiconductor.

Small Size and Low Cost UHF RFID Tag Antenna Mountable on Metallic Objects

Directory of Open Access Journals (Sweden)

Sergio López-Soriano

2015-01-01

Full Text Available Reducing tag size while maintaining good performance is one of the major challenges in radio-frequency identification applications (RFID, in particular when labeling metallic objects. In this contribution, a small size and low cost tag antenna for identifying metal objects in the European UHF band (865–868 MHz is presented. The antenna consists of a transmission line mounted on an inexpensive thin dielectric which is proximity-coupled to a short-ended patch mounted on FR4 substrate. The overall dimensions of the tag are 33.5 × 30 × 3.1 mm. Experimental results show that, for an EIRP of 3.2 W (European regulations, such a small and cheap tag attains read ranges of about 5 m when attached to a metallic object.

Suppression of leaky expression of adenovirus genes by insertion of microRNA-targeted sequences in the replication-incompetent adenovirus vector genome

Directory of Open Access Journals (Sweden)

Kahori Shimizu

2014-01-01

Full Text Available Leaky expression of adenovirus (Ad genes occurs following transduction with a conventional replication-incompetent Ad vector, leading to an induction of cellular immunity against Ad proteins and Ad protein-induced toxicity, especially in the late phase following administration. To suppress the leaky expression of Ad genes, we developed novel Ad vectors by incorporating four tandem copies of sequences with perfect complementarity to miR-122a or miR-142-3p into the 3′-untranslated region (UTR of the E2A, E4, or pIX gene, which were mainly expressed from the Ad vector genome after transduction. These Ad vectors easily grew to high titers comparable to those of a conventional Ad vector in conventional 293 cells. The leaky expression of these Ad genes in mouse organs was significantly suppressed by 2- to 100-fold, compared with a conventional Ad vector, by insertion of the miRNA-targeted sequences. Notably, the Ad vector carrying the miR-122a–targeted sequences into the 3′-UTR of the E4 gene expressed higher and longer-term transgene expression and more than 20-fold lower levels of all the Ad early and late genes examined in the liver than a conventional Ad vector. miR-122a–mediated suppression of the E4 gene expression in the liver significantly reduced the hepatotoxicity which an Ad vector causes via both adaptive and non-adaptive immune responses.

A Block Iterative Finite Element Model for Nonlinear Leaky Aquifer Systems

Science.gov (United States)

Gambolati, Giuseppe; Teatini, Pietro

1996-01-01

A new quasi three-dimensional finite element model of groundwater flow is developed for highly compressible multiaquifer systems where aquitard permeability and elastic storage are dependent on hydraulic drawdown. The model is solved by a block iterative strategy, which is naturally suggested by the geological structure of the porous medium and can be shown to be mathematically equivalent to a block Gauss-Seidel procedure. As such it can be generalized into a block overrelaxation procedure and greatly accelerated by the use of the optimum overrelaxation factor. Results for both linear and nonlinear multiaquifer systems emphasize the excellent computational performance of the model and indicate that convergence in leaky systems can be improved up to as much as one order of magnitude.

Effect of concentrate feeder design on performance, eating and animal behavior, welfare, ruminal health, and carcass quality in Holstein bulls fed high-concentrate diets.

Science.gov (United States)

Verdú, M; Bach, A; Devant, M

2015-06-01

A total of 240 Holstein bulls (121 ± 2.0 kg initial BW; 99 ± 1.0 d of age), from 2 consecutive fattening cycles, were randomly allocated in 1 of 6 pens and assigned to 1 of the 3 treatments consisting of different concentrate feeder designs: a control feeder with 4 feeding spaces (CF), a feeder with less concentrate capacity (CFL), and a single-space feeder with lateral protections (SF). Each pen had a straw feeder and a drinker. All animals were fed a high-concentrate diet for ad libitum intake. Concentrate consumption was recorded daily using a computerized feeder, straw consumption was recorded weekly, and BW was recorded every 14 d. Animal behavior was registered on d 1, 3, 5, 8, and 14 and every 28 d by scan sampling. Eating behavior at concentrate feeders was filmed on d 12, 125, and 206. On d 7, 120, and 204, samples of rumen contents were collected for measurement of pH and VFA and blood samples were obtained to analyze NEFA, haptoglobin, glucose, and insulin. Animals were slaughtered after 223 d, and HCW and lesions of the rumen wall and liver were recorded. The accumulative concentrate consumption per animal tended (P = 0.09) to be greater with CF than with CFL and SF. Also, CV of concentrate consumption was greater (P carcass data. Also, no differences among treatments in rumen wall evaluation and liver abscesses were observed. At 7 and 204 d of study, SF bulls had greater (P animal welfare in Holstein bulls fed high-concentrate diets. However, at the beginning, there was evidence that animals fed using SF had problems with adaptation.

Keratinocytes propagated in serum-free, feeder-free culture conditions fail to form stratified epidermis in a reconstituted skin model.

Directory of Open Access Journals (Sweden)

Rebecca Lamb

Full Text Available Primary human epidermal stem cells isolated from skin tissues and subsequently expanded in tissue culture are used for human therapeutic use to reconstitute skin on patients and to generate artificial skin in culture for academic and commercial research. Classically, epidermal cells, known as keratinocytes, required fibroblast feeder support and serum-containing media for serial propagation. In alignment with global efforts to remove potential animal contaminants, many serum-free, feeder-free culture methods have been developed that support derivation and growth of these cells in 2-dimensional culture. Here we show that keratinocytes grown continually in serum-free and feeder-free conditions were unable to form into a stratified, mature epidermis in a skin equivalent model. This is not due to loss of cell potential as keratinocytes propagated in serum-free, feeder-free conditions retain their ability to form stratified epidermis when re-introduced to classic serum-containing media. Extracellular calcium supplementation failed to improve epidermis development. In contrast, the addition of serum to commercial, growth media developed for serum-free expansion of keratinocytes facilitated 3-dimensional stratification in our skin equivalent model. Moreover, the addition of heat-inactivated serum improved the epidermis structure and thickness, suggesting that serum contains factors that both aid and inhibit stratification.

Operation of a cell feeder for coal controlled by a frequency converter. [Czechoslovakia

Energy Technology Data Exchange (ETDEWEB)

Stonawski, J; Sikora, G

1984-02-01

Steam boiler of the Trinec coal-fired power plant with a capacity of 125 t/h, 545 C, 9.5 MPa was equipped with a screw coal feeder with the KT26A-6 Winter-Eichberg motor with a transformer. The screw fee

Some software issues in mapping of power distribution feeders

International Nuclear Information System (INIS)

Mufti, I.A.

1994-01-01

This paper is about the in-house developed software for distribution feeders mapping project. It first gives birds eye view of the project, highlight its technical complexity in management and logistics, introduced by sheer size of the project. It gives an overview of the software developed and the moves on to describe circuit tracing, circuit model, leaves isolation (for tree structured network) and backtracking in more detail among many different parts of software, description of all which is not possible because of space limitations. (author)

Feeder use predicts both acquisition and transmission of a contagious pathogen in a North American songbird.

Science.gov (United States)

Adelman, James S; Moyers, Sahnzi C; Farine, Damien R; Hawley, Dana M

2015-09-22

Individual heterogeneity can influence the dynamics of infectious diseases in wildlife and humans alike. Thus, recent work has sought to identify behavioural characteristics that contribute disproportionately to individual variation in pathogen acquisition (super-receiving) or transmission (super-spreading). However, it remains unknown whether the same behaviours enhance both acquisition and transmission, a scenario likely to result in explosive epidemics. Here, we examined this possibility in an ecologically relevant host-pathogen system: house finches and their bacterial pathogen, Mycoplasma gallisepticum, which causes severe conjunctivitis. We examined behaviours likely to influence disease acquisition (feeder use, aggression, social network affiliations) in an observational field study, finding that the time an individual spends on bird feeders best predicted the risk of conjunctivitis. To test whether this behaviour also influences the likelihood of transmitting M. gallisepticum, we experimentally inoculated individuals based on feeding behaviour and tracked epidemics within captive flocks. As predicted, transmission was fastest when birds that spent the most time on feeders initiated the epidemic. Our results suggest that the same behaviour underlies both pathogen acquisition and transmission in this system and potentially others. Identifying individuals that exhibit such behaviours is critical for disease management. © 2015 The Author(s).

Busbar arcs at large fusion magnets: Conductor to feeder tube arcing model experiments with the LONGARC device

Energy Technology Data Exchange (ETDEWEB)

Klimenko, Dmitry, E-mail: dmitry.klimenko@kit.edu; Pasler, Volker

2014-10-15

Highlights: •The LONGARC device was successfully implemented for busbar to feeder tubes arcing model experiments. •Arcing at an ITER busbar inside its feeder tube was simulated in scaled model experiments. •The narrower half tubes imply a slight increase of the arc propagation speed in compare to full tube experiments. •All simulated half tubes experiments show severe damage indicating that the ITER inner feeder tube will not withstand a busbar arc. -- Abstract: Electric arcs moving along the power cables (the so-called busbars) of the toroidal field (TF) coils of ITER may reach and penetrate the cryostat wall. Model experiments with the new LONGARC device continue the VACARC (VACuum ARC) experiments that were initiated to investigate the propagation and destruction mechanisms of busbar arcs in small scale [1]. The experiments are intended to support the development and validation of a numerical model. LONGARC overcomes the space limitations inside VACARC and allows also for advanced 1:3 (vs. ITER full scale) model setups. The LONGARC device and first results are presented below.

Measurements of local mass transfer coefficient of Flow Accelerated Corrosion at feeder outlet pipes in CANDU using Plaster of Paris method

International Nuclear Information System (INIS)

Hyuk Kwon; Dong Un Seo; Goon-Cherl Park

2005-01-01

Full text of publication follows: Flow Accelerated Corrosion (FAC) is a corrosion mechanism that results in wall thinning in piping systems and components. FAC on carbon steels in pure water has occurred in a number of industry and power plant. A pipe wall thinning due to the FAC at nuclear power plant is just reported in confined to carbon steel pipe on the secondary system which does not equip a radioactive component. Recently, at Canadian Deuterium Uranium type reactor, it is reported that the feeder lines suffer the wall thinning on the primary system to equip 380 feeder pipes. Differently from the fast FAC rate of the secondary system on PWR, FAC rate of feeder pipes on CANDU is not more than the 0.2 mm/year. Although the FAC rate of feeder pipe is relatively slow, the narrow thickness margin of 2.6089 mm is endangered sufficiently by only the slow FAC rate. The FAC is governed by the mass transfer coefficient which is determined by the flow field. To well predict the FAC rate, mass transfer coefficient should be well measured or calculated. New measurement method of mass transfer coefficient is developed to obtain the coefficient for the complex shape like feeder pipe. The method evaluated the naphthalene sublimation method to apply it under the water flow. The naphthalene sublimation method can be used to study mass and heat transfer with confidence for a variety of applications, but with certain restrictions. At present, Plaster of paris method can modified the sublimation method to overcome the restrictions. This method is particularly useful in complex flows on geometries and for flows with large gradients in wall transport rate. The test specimen can be easily prepared by several methods, including dipping, machining, spraying, and casting. The local transfer coefficients can be determined with high accuracy and in detail by automated measurement systems that eliminate most human errors during the measurement process. To evaluate the method, the

DYNAMICS OF VIBRATION FEEDERS WITH A NONLINEAR ELASTIC CHARACTERISTIC

Directory of Open Access Journals (Sweden)

V. I. Dyrda

2017-04-01

Full Text Available Purpose. Subject to the smooth and efficient operation of each production line, is the use of vehicles transporting high specification. It worked well in practice for transporting construction machines, which are used during the vibration. The use of vibration machines requires optimization of their operation modes. In the form of elastic link in them are increasingly using rubber-metallic elements, which are characterized by nonlinear damping properties. So it is necessary to search for new, more modern, methods of calculation of dynamic characteristics of the vibration machines on the properties of rubber as a cushioning material. Methodology. The dynamics of vibration machine that is as elastic rubber block units and buffer shock absorbers limiting the amplitude of the vibrations of the working body. The method of determining amplitude-frequency characteristics of the vibrating feeder is based on the principle of Voltaire, who in the calculations of the damping properties of the dampers will allow for elastic-hereditary properties of rubber. When adjusting the basic dynamic stiffness of the elastic ties and vibratory buffers, using the principle of heredity rubber properties, determine the dependence of the amplitude of the working body of the machine vibrations. This method is called integro-operator using the fractional-exponential kernels of relaxation. Findings. Using the derived formula for determining the amplitude of the resonance curve is constructed one-mass nonlinear system. It is established that the use of the proposed method of calculation will provide a sufficiently complete description of the damping parameters of rubber-metallic elements and at the same time be an effective means of calculating the amplitude-frequency characteristics of nonlinear vibration systems. Originality. The authors improved method of determining damping characteristics of rubber-metallic elements and the amplitude-frequency characteristics of nonlinear

Spontaneous decay of a single quantum dot coupled to a metallic slot waveguide in the presence of leaky plasmonic modes

DEFF Research Database (Denmark)

Chen, Yuntian; Gregersen, Niels; Nielsen, Torben Roland

2010-01-01

in which the metallic slot waveguide is embedded. Compared to the ideal case of a homogenous dielectric environment, the coupling efficiency of an emitter to a metallic slot waveguide is significantly reduced. We attribute the reduction to the coupling to leaky plasmonic modes. By increasing the refractive...

Classification of Alzheimer's Disease Based on Eight-Layer Convolutional Neural Network with Leaky Rectified Linear Unit and Max Pooling.

Science.gov (United States)

Wang, Shui-Hua; Phillips, Preetha; Sui, Yuxiu; Liu, Bin; Yang, Ming; Cheng, Hong

2018-03-26

Alzheimer's disease (AD) is a progressive brain disease. The goal of this study is to provide a new computer-vision based technique to detect it in an efficient way. The brain-imaging data of 98 AD patients and 98 healthy controls was collected using data augmentation method. Then, convolutional neural network (CNN) was used, CNN is the most successful tool in deep learning. An 8-layer CNN was created with optimal structure obtained by experiences. Three activation functions (AFs): sigmoid, rectified linear unit (ReLU), and leaky ReLU. The three pooling-functions were also tested: average pooling, max pooling, and stochastic pooling. The numerical experiments demonstrated that leaky ReLU and max pooling gave the greatest result in terms of performance. It achieved a sensitivity of 97.96%, a specificity of 97.35%, and an accuracy of 97.65%, respectively. In addition, the proposed approach was compared with eight state-of-the-art approaches. The method increased the classification accuracy by approximately 5% compared to state-of-the-art methods.

A low cost integrated transceiver for mobile UHF passive RFID reader applications

Energy Technology Data Exchange (ETDEWEB)

Wang Jingchao; Zhang Chun; Chi Baoyong; Wang Ziqiang; Li Fule; Wang Zhihua, E-mail: wangjc@gmail.co [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

2009-09-15

A low cost integrated transceiver for mobile UHF passive RFID reader applications is implemented in a 0.18-{mu}m CMOS process. The transceiver contains an OOK modulator and a power amplifier in the transmitter chain, an IQ direct-down converter, variable-gain amplifiers, channel-select filters and a 10-bit ADC in the receiver chain. The measured output P{sub 1DB} power of the transmitter is 17.6 dBm and the measured receiver sensitivity is -70 dBm. The on-chip integer N synthesizer achieves a frequency resolution of 200 kHz with a phase noise of -104 dBc/Hz at 100 kHz frequency offset and -120.83 dBc/Hz at 1 MHz frequency offset. The transmitter, the receiver and the frequency synthesizer consume 201.34, 25.3 and 54 mW, respectively. The chip has a die area of 4 x 2.5 mm{sup 2} including pads.

A low cost integrated transceiver for mobile UHF passive RFID reader applications

International Nuclear Information System (INIS)

Wang Jingchao; Zhang Chun; Chi Baoyong; Wang Ziqiang; Li Fule; Wang Zhihua

2009-01-01

A low cost integrated transceiver for mobile UHF passive RFID reader applications is implemented in a 0.18-μm CMOS process. The transceiver contains an OOK modulator and a power amplifier in the transmitter chain, an IQ direct-down converter, variable-gain amplifiers, channel-select filters and a 10-bit ADC in the receiver chain. The measured output P 1DB power of the transmitter is 17.6 dBm and the measured receiver sensitivity is -70 dBm. The on-chip integer N synthesizer achieves a frequency resolution of 200 kHz with a phase noise of -104 dBc/Hz at 100 kHz frequency offset and -120.83 dBc/Hz at 1 MHz frequency offset. The transmitter, the receiver and the frequency synthesizer consume 201.34, 25.3 and 54 mW, respectively. The chip has a die area of 4 x 2.5 mm 2 including pads.

Design and implementation of an ultra-low power passive UHF RFID tag

International Nuclear Information System (INIS)

Shen Jinpeng; Wang Xin'an; Liu Shan; Zong Hongqiang; Huang Jinfeng; Yang Xin; Feng Xiaoxing; Ge Binjie

2012-01-01

This paper presents a fully integrated passive UHF RFID tag chip complying with the ISO18000-6B protocol. The tag chip includes an RF/analog front-end, a baseband processor, and a 512-bit EEPROM memory. To improve power conversion efficiency, a Schottky barrier diode based rectifier is adopted. A novel voltage reference using the peaking current source is discussed in detail, which can meet the low-power, low-voltage requirement while retaining circuit simplicity. Most of the analog blocks are designed to work under sub-1 V to reduce power consumption, and several practical methods are used to further reduce the power consumption of the baseband processor. The whole tag chip is implemented in a TSMC 0.18 μm CMOS process with a die size of 800 × 800 μm 2 . Measurement results show that the total power consumption of the tag chip is only 7.4 μW with a sensitivity of −12 dBm. (semiconductor integrated circuits)

Differences in carotenoid accumulation among three feeder-cricket species: implications for carotenoid delivery to captive insectivores.

Science.gov (United States)

Ogilvy, Victoria; Fidgett, Andrea L; Preziosi, Richard F

2012-01-01

There are a limited number of feeder-invertebrates available to feed captive insectivores, and many are deficient in certain nutrients. Gut-loading is used to increase the diversity of nutrients present in the captive insectivore diet; however, little is known about delivery of carotenoids via gut-loading. Carotenoids may influence health and reproduction due to their roles in immune and antioxidant systems. We assessed interspecific variation in carotenoid accumulation and retention in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus) fed one of three diets (wheat-bran, fish-food based formulated diet, and fresh fruit and vegetables). Out of the three species of feeder-cricket in the fish-food-based dietary treatment group, G. bimaculatus had the greatest total carotenoid concentration. All cricket species fed the wheat-bran diet had very low carotenoid concentrations. Species on the fish-food-based diet had intermediate carotenoid concentrations, and those on the fruit and vegetable diet had the highest concentrations. Carotenoid retention was poor across all species. Overall, this study shows that, by providing captive insectivores with G. bimaculatus crickets recently fed a carotenoid-rich diet, the quantity of carotenoids in the diet can be increased. © 2011 Wiley Periodicals, Inc.

Dc to ac field conversion due to leaky-wave excitation in a plasma slab behind an ionization front

International Nuclear Information System (INIS)

Kostin, V A; Vvedenskii, N V

2015-01-01

We present a way for generating coherent tunable electromagnetic radiation through dc to ac field conversion by an ionization front. The conversion is caused by the excitation of leaky waves behind the transversely limited ionization front propagating in a uniform electrostatic field. This differs significantly from the well-known dc-to-ac-radiation-converter models which consider Doppler-like frequency conversion by a transversely unlimited ionization front propagating in a spatially periodic electric field. We explore the dispersion properties and excitation of these leaky waves radiated through the transverse plasma boundary at the Cherenkov angle to the direction of propagation of a superluminal ionization front as dependent on the parameters of the plasma produced and on the speed of the ionization front. It is shown that not only the center frequency but also the duration and waveform of the generated pulse may significantly depend on the speed of the ionization front. The results indicate the possibility of using such converters based on planar photoconductive antennas to create sources of microwave and terahertz radiation with controllable waveforms that are transformed from video to radio pulse when the angle of incident ionizing radiation is tuned. (paper)

Passive UHF RFID Tags with Specific Printed Antennas for Dielectric and Metallic Objects Applications

Directory of Open Access Journals (Sweden)

K. Siakavara

2017-09-01

Full Text Available Design process and respective results for the synthesis of specific Radiofrequency Identification(RFID tag antennas, suitable for dielectric and metallic objects, are presented. The antennas were designed for the UHF(865MHz-869MHz band and their basic configuration is that of the printed spiral type. Six modification steps to the classical spiral layout are proposed and it was proved that they can lead to tags with high readability and reading distances up to 10m when designed for dielectric object and up to 7m in the case of metallic objects. The results of the measurements of the fabricated tags are explained via theoretical evaluations which take into account reflection phenomena, that are present in a real environment at which the tags are used.

Normal overall leakiness of microvasculature for albumin in patients with chronic obstructive lung disease (COLD)

DEFF Research Database (Denmark)

Kok-Jensen, A; Henriksen, Jens Henrik Sahl

1984-01-01

The overall extravasation rate of albumin, TER (i.e. the fraction of the intravascular albumin mass (IVM) passing into, and during steady state returning from, the extravascular space per unit time) was determined from the disappearance of i.v. injected radioiodinated serum albumin in seven...... controls 6.0% IVM/h (range 4.3-7.4), indicating that no significant change in microvascular leakiness to albumin could be found in patients with COLD. Thus, the results bring no support to a generally increased microvascular permeability to proteins in patients with COLD....

Using automated feeders to wean calves fed large amounts of milk according to their ability to eat solid feed.

Science.gov (United States)

de Passillé, Anne Marie; Rushen, Jeffrey

2016-05-01

Dairy calves weaned off milk at an early age show signs of hunger and can lose weight. We examined whether using automated feeders to wean calves according to individual voluntary solid feed intake reduced the effects of weaning. Female Holstein calves were housed in groups of 5 to 9. All calves were fed 12 L/d milk and ad libitum grain starter and hay from automated feeders immediately after grouping, and were allocated to 3 weaning strategies: (1) early-weaned (EW; n=14): weaning began on d 40, and milk allowance gradually decreased until weaning was complete on d 48; (2) late-weaned (LW; n=14): weaning began on d 80 and was completed on d 89; (3) weaned by starter intake (WSI; n=28): weaning began when calves consumed 200g/d of starter and was completed when the calves consumed 1,400g/d. Each day, the automated feeders recorded quantities of milk, starter, and hay eaten by all calves, as well as the frequency of visits to the milk feeder; we used unrewarded visit frequency as a sign of hunger. Body weights (BW) were recorded weekly. We estimated daily digestible energy (DE) intake for each calf based on the milk, hay, and starter consumed. Average daily gains (ADG) were expressed as percent of BW. For calves in WSI, weaning began at 54.7±18.9 d (mean ± SD) of age, the duration of weaning was 21.1±10.6 d, and weaning ended at 75.8±10.7 d of age. Both LW and WSI calves had better ADG from wk 3 to 13 than EW calves. Calves in the WSI group drank less milk and ate more starter than LW calves but had similar ADG. During the period of weaning, EW calves made more unrewarded visits to the milk feeder than LW and WSI calves. Three EW calves lost weight during weaning, whereas all LW and WSI calves gained weight. Calves differ greatly in when they begin to eat solid feed and how quickly they increase the intake in response to a decrease in milk allowance. An advantage of automated feeders is that calves can be weaned at variable ages depending on their ability and

Introducing tool-based feeders to zoo-housed chimpanzees as a cognitive challenge: spontaneous acquisition of new types of tool use and effects on behaviours and use of space.

OpenAIRE

Yamanashi, Yumi; Matsunaga, Masayuki; Shimada, Kanae; Kado, Ryuichiro; Tanaka, Masayuki

2016-01-01

Cognitively challenging environments are vital to the welfare of captive animals. However, practical enrichment devices that can facilitate animals’ natural behaviours and accommodate individual variation are still limited. We created two types of feeders to facilitate tool-using behaviour in captive chimpanzees: pounding and dipping feeders. The pounding feeder was inspired by pestle-pounding behaviour observed in wild chimpanzees, and we expected that chimpanzees would pound soft foods. The...

A Novel RFID Sensing System Using Enhanced Surface Wave Technology for Battery Exchange Stations

Directory of Open Access Journals (Sweden)

Yeong-Lin Lai

2014-01-01

Full Text Available This paper presents a novel radio-frequency identification (RFID sensing system using enhanced surface wave technology for battery exchange stations (BESs of electric motorcycles. Ultrahigh-frequency (UHF RFID technology is utilized to automatically track and manage battery and user information without manual operation. The system includes readers, enhanced surface wave leaky cable antennas (ESWLCAs, coupling cable lines (CCLs, and small radiation patches (SRPs. The RFID sensing system overcomes the electromagnetic interference in the metallic environment of a BES cabinet. The developed RFID sensing system can effectively increase the efficiency of BES operation and promote the development of electric vehicles which solve the problem of air pollution as well as protect the environment of the Earth.

Tits recognize the potential dangers of predators and harmless birds in feeder experiments

Czech Academy of Sciences Publication Activity Database

Tvardíková, Kateřina; Fuchs, R.

2012-01-01

Roč. 30, č. 1 (2012), s. 157-165 ISSN 0289-0771 Grant - others:AV ČR(CZ) IAA601410803 Institutional research plan: CEZ:AV0Z50070508 Keywords : feeders * predator recognition * risk Subject RIV: EH - Ecology, Behaviour Impact factor: 1.000, year: 2012 http://www.springerlink.com/content/2338033t30261604/fulltext.pdf

Wean-to-finish feeder space availability effects on nursery and finishing pig performance and total tract digestibility in a commercial setting when feeding dried distillers grains with solubles.

Science.gov (United States)

Weber, E K; Stalder, K J; Patience, J F

2015-04-01

The study objectives were to determine nursery phase feeder space allowance effects on pig performance when double stocked and, second, to determine feeder space allowance and dried distillers grains with solubles (DDGS) inclusion level effects on pig performance and nutrient digestibility during the growing-finishing phase. This study was performed on the same group of pigs within a commercial wean-finish system. For the nursery phase, a completely randomized design was used to compare 3 feeder space allowance treatments (2.1, 2.5, and 2.9 cm/pig). A total of 3,720 pigs were randomly allotted to same-sex pens (10 feeders/treatment) housing 62 pigs/pen. Thirty 7-hole, double-sided feeders were utilized in the study. Differing linear feeder space treatments were established by blocking off sections for the nursery and grow-finish portions of this experiment. All pigs were provided equal floor space (0.26 m2/pig). In the grow-finish phase, a total of 1,860 pigs (n = 60 pens) were utilized in a 2 × 3 factorial design with 3 feeder space allowances (4.1, 4.9, or 5.7 cm/pig) and 2 dietary DDGS treatments (30% [D30] or 60% [D60]). Fecal and diet samples were collected and analyzed to estimate apparent total tract digestibility percentage (ATTD %). In the nursery portion of the trial, there was no feeder space treatment effect on ADG, ADFI, or feed efficiency (P > 0.10) from weaning to d 56 postweaning or during any weigh period. In the grow-finish portion of the trial, feeder space allowance and DDGS inclusion level did not affect ADG, ADFI, or feed efficiency (P > 0.05) from d 57 postweaning to market. Pigs fed the D30 diet had greater HCW, percent yield, and loin depth than those on the D60 diet (P feeder space allowance did not impact pig performance during the nursery or grow-finish production phases. Inclusion of DDGS at higher levels will decrease ADFI but not ADG or efficiency when isocaloric diets are fed. The inclusion level of DDGS does impact HCW and percent

Effect of feeder space during the growing and laying periods and the rate of feed increase at the onset of lay on broiler breeder female reproductive function.

Science.gov (United States)

Leksrisompong, N; Romero-Sanchez, H; Oviedo-Rondón, E O; Brake, J

2014-07-01

A study was conducted to examine how 2 feeder space allocations during the rearing period followed by 2 feeder space allocations after photostimulation and 2 female feeding to peak programs (fast or slow) affected female broiler breeder reproductive performance and mortality. Sixteen pens of 76 breeder females each were equipped with either 4 tube feeders with a 132 cm circumference pan (7.0 cm/female) or 6 feeders (10.4 cm/female) to 21 wk of age. Thereafter, 64 females were moved to breeding pens, photostimulated, and fed sex-separate from either 3 (6.2 cm/female) or 5 (10.3 cm/female) feeders with either fast or slow feeding to peak feeding programs applied to complete a 2 × 2 × 2 factorial design. Seven males that were separately reared in a similar manner were added per pen. Individual female BW was determined at 6, 20, and 32 wk of age and BW uniformity assessed. Greater feeder space during rearing increased BW at 32 wk of age, whereas greater feeder space during lay or slow feeding to peak decreased BW at 32 wk. There were no differences in BW uniformity. Hens from the 10.4 to 10.3 cm/female combination produced a significantly greater number of eggs as compared with the 7.0 to 10.3 cm/female and 10.4 to 6.2 cm/female combinations with the 7.0 to 6.2 cm/female combination intermediate. Percentage hen-day egg production of the 10.4 to 10.3 cm/female combination hens was significantly greater than all other combinations. Livability was improved in the 10.4 to 10.3 cm/female combination relative to the 7.0 to 10.3 cm/female combination with the others intermediate. The fast feeding to peak program increased yolk weight as well as yolk:albumen ratio at 28 and 30 wk of age, but egg weight did not differ. These data indicated that increased or decreased feeder space between the growing and laying periods did not affect broiler breeder female BW, uniformity, egg weight, fertility, or hatchability. The 10.3 cm/female laying feeder space exhibited the best hen

Intestinal CYP2E1: A mediator of alcohol-induced gut leakiness

Directory of Open Access Journals (Sweden)

Christopher B. Forsyth

2014-01-01

Full Text Available Chronic alcohol use can result in many pathological effects including alcoholic liver disease (ALD. While alcohol is necessary for the development of ALD, only 20–30% of alcoholics develop alcoholic steatohepatitis (ASH with progressive liver disease leading to cirrhosis and liver failure (ALD. This suggests that while chronic alcohol consumption is necessary it is not sufficient to induce clinically relevant liver damage in the absence of a secondary risk factor. Studies in rodent models and alcoholic patients show that increased intestinal permeability to microbial products like endotoxin play a critical role in promoting liver inflammation in ALD pathogenesis. Therefore identifying mechanisms of alcohol-induced intestinal permeability is important in identifying mechanisms of ALD and for designing new avenues for therapy. Cyp2e1 is a cytochrome P450 enzyme that metabolizes alcohol has been shown to be upregulated by chronic alcohol use and to be a major source of oxidative stress and liver injury in alcoholics and in animal and in vitro models of chronic alcohol use. Because Cyp2e1 is also expressed in the intestine and is upregulated by chronic alcohol use, we hypothesized it could play a role in alcohol-induced intestinal hyperpermeability. Our in vitro studies with intestinal Caco-2 cells and in mice fed alcohol showed that circadian clock proteins CLOCK and PER2 are required for alcohol-induced permeability. We also showed that alcohol increases Cyp2e1 protein and activity but not mRNA in Caco-2 cells and that an inhibitor of oxidative stress or siRNA knockdown of Cyp2e1 prevents the increase in CLOCK or PER2 proteins and prevents alcohol-induced hyperpermeability. With our collaborators we have also shown that Cyp2e1 knockout mice are resistant to alcohol-induced gut leakiness and liver inflammation. Taken together our data support a novel Cyp2e1-circadian clock protein mechanism for alcohol-induced gut leakiness that could provide new

Effect of stall design on dairy calf transition to voluntary feeding on an automatic milk feeder after introduction to group housing.

Science.gov (United States)

Wilson, Tanya R; LeBlanc, Stephen J; DeVries, Trevor J; Haley, Derek B

2018-06-01

Automatic milk feeders (AMF) for young dairy calves are widely used in the dairy industry. These feeders are thought to have benefits for calf health and welfare and may reduce labor required for feeding; however, little is known about how calves adapt to feeding with AMF. The objective of this study was to observe the effects of feeding stall design on calves learning to use the AMF. The hypothesis was that solid side stalls, compared with steel bar stalls, would result in a longer latency to approach and feed from the AMF without assistance. A total of 147 Holstein calves (80 male and 67 female) were enrolled at 4 d of age, introduced to a group pen, and, at the same time, trained on an AMF. For training, calves were allowed to suck on the trainer's fingers and guided to the teat. Calves were allocated to 1 of 2 stall designs at the pen level, depending on which treatment cohort they were born into, either with steel bar stall walls (n = 46 male, 34 female calves) or with solid side stall walls (n = 34 male, 33 female calves). For 72 h after introductory training on the AMF, data from the feeders were collected and calf behavior was monitored by video. Outcomes measured included latency to first voluntary visit to the feeder and to first feeding, time spent in the feeder, amount of milk consumed over 72 h, number of retraining sessions required (retrained if linear regression models or a Poisson model for the outcome of retraining. For certain outcomes the effects of stall design interacted with difficulty of training (willingness to enter feeder and drink); for the 38% of calves that were scored as moderately difficult to train on a scale of easy, moderate, or difficult, treatment (stall design) differences were detected. These calves took 2× longer to lick or bite toward the nipple, 2× longer to first voluntarily feeding, and consumed less milk over 72 h following training when trained on the steel bar stall design. These results suggest simple features of a

Hybrid RSOA and fibre raman amplified long reach feeder link for WiMAX-on-fibre

DEFF Research Database (Denmark)

Amaya Fernández, Ferney Orlando; Martinez, Javier; Yu, Xianbin

2009-01-01

A distributed fibre Raman amplified long reach optical access feeder link using a reflective semiconductor optical amplifier in the remote base station is experimentally demonstrated for supporting WiMAXover- fibre transmission. The measured values for the error vector magnitude for quadrature...

Development of an extruder-feeder biomass direct liquefaction process

Energy Technology Data Exchange (ETDEWEB)

White, D.H.; Wolf, D. (Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering)

1991-10-01

As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE's Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

Adjusting the weaning age of calves fed by automated feeders according to individual intakes of solid feed.

Science.gov (United States)

de Passillé, A M; Rushen, J

2012-09-01

When weaned at the ages typical of commercial dairy production, dairy calves usually show reduced growth rates, lowered energy intake, and increased behavioral signs of hunger, reflecting their difficulty in switching from a milk diet to solid feed. However, large differences exist between calves in their ability to adapt to solid feed, and automated feeders allow the age of weaning to be adjusted to an individual calf's intake of solid feed. We examined the effects of weaning according to solid feed intake on age at weaning, feed intake, and behavioral signs of hunger. In a 2×2 factorial design, 60 female Holstein calves in groups of 8 and fed milk, grain starter, and hay from automated feeders began to be weaned when their voluntary intake of grain starter was either 400 g/d (high start) or 200 g/d (low start), with weaning completed when their voluntary intakes of starter were either 1,600 g/d (high end) or 800 g/d (low end). Digestible energy intakes were calculated from milk, starter and hay intakes, corrected for body weights, calves were weighed, and the frequency of visits to the milk feeders were measured each day. The main effects and interactions between treatments were tested with ANOVA. Large differences were observed between calves in the age at which weaning was complete, with weaning completed earlier for low-end calves compared with high-end calves. No treatment effects (either of start amount or end amount) on intakes of milk, starter, or hay or on weight gains occurred. However, the calves that began weaning earlier had longer durations of weaning, greater growth rates from d 20 to 87, and were heavier on d 87, and had lower milk intakes, higher starter intakes, higher hay intakes, and a greater digestible energy intake, but showed more unrewarded visits to the milk feeder. Adjusting the age at which individual calves are weaned off milk according to their ability to eat solid feed can reduce the age at which weaning occurs while reducing the

A local leaky-box model for the local stellar surface density-gas surface density-gas phase metallicity relation

Science.gov (United States)

Zhu, Guangtun Ben; Barrera-Ballesteros, Jorge K.; Heckman, Timothy M.; Zakamska, Nadia L.; Sánchez, Sebastian F.; Yan, Renbin; Brinkmann, Jonathan

2017-07-01

We revisit the relation between the stellar surface density, the gas surface density and the gas-phase metallicity of typical disc galaxies in the local Universe with the SDSS-IV/MaNGA survey, using the star formation rate surface density as an indicator for the gas surface density. We show that these three local parameters form a tight relationship, confirming previous works (e.g. by the PINGS and CALIFA surveys), but with a larger sample. We present a new local leaky-box model, assuming star-formation history and chemical evolution is localized except for outflowing materials. We derive closed-form solutions for the evolution of stellar surface density, gas surface density and gas-phase metallicity, and show that these parameters form a tight relation independent of initial gas density and time. We show that, with canonical values of model parameters, this predicted relation match the observed one well. In addition, we briefly describe a pathway to improving the current semi-analytic models of galaxy formation by incorporating the local leaky-box model in the cosmological context, which can potentially explain simultaneously multiple properties of Milky Way-type disc galaxies, such as the size growth and the global stellar mass-gas metallicity relation.

Flow Generated by a Partially Penetrating Well in a Leaky Two-Aquifer System with a Storative Semiconfining Layer

Science.gov (United States)

Sepulveda, N.; Rohrer, K.

2008-05-01

The permeability of the semiconfining layers of the highly productive Floridan Aquifer System may be large enough to invalidate the assumptions of the leaky aquifer theory. These layers are the intermediate confining and the middle semiconfining units. The analysis of aquifer-test data with analytical solutions of the ground-water flow equation developed with the approximation of a low hydraulic conductivity ratio between the semiconfining layer and the aquifer may lead to inaccurate hydraulic parameters. An analytical solution is presented here for the flow in a confined leaky aquifer, the overlying storative semiconfining layer, and the unconfined aquifer, generated by a partially penetrating well in a two-aquifer system, and allowing vertical and lateral flow components to occur in the semiconfining layer. The equations describing flow caused by a partially penetrating production well are solved analytically to provide a method to accurately determine the hydraulic parameters in the confined aquifer, semiconfining layer, and unconfined aquifer from aquifer-test data. Analysis of the drawdown data from an aquifer test performed in central Florida showed that the flow solution presented here for the semiconfining layer provides a better match and a more unique identification of the hydraulic parameters than an analytical solution that considers only vertical flow in the semiconfining layer.

Design and implementation of a high sensitivity fully integrated passive UHF RFID tag

International Nuclear Information System (INIS)

Li Shoucheng; Wang Xin'an; Lin Ke; Shen Jinpeng; Zhang Jinhai

2014-01-01

A fully integrated passive UHF RFID tag complying with the ISO18000-6B protocol is presented, which includes an analog front-end, a baseband processor, and an EEPROM memory. To extend the communication range, a high efficiency differential-drive CMOS rectifier is adopted. A novel high performance voltage limiter is used to provide a stable limiting voltage, with a 172 mV voltage variation against temperature variation and process dispersion. The dynamic band-enhancement technique is used in the regulator circuit to improve the regulating capacity. A rail-to-rail hysteresis comparator is adopted to demodulate the signal correctly in any condition. The whole transponder chip is implemented in a 0.18 μm CMOS process, with a die size of 900 × 800 μm 2 . Our measurement results show that the total power consumption of the tag chip is only 6.8 μW, with a sensitivity of −13.5 dBm (semiconductor integrated circuits)

First UHF Implementation of the Incremental Scheme for Open-Shell Systems.

Science.gov (United States)

Anacker, Tony; Tew, David P; Friedrich, Joachim

2016-01-12

The incremental scheme makes it possible to compute CCSD(T) correlation energies to high accuracy for large systems. We present the first extension of this fully automated black-box approach to open-shell systems using an Unrestricted Hartree-Fock (UHF) wave function, extending the efficient domain-specific basis set approach to handle open-shell references. We test our approach on a set of organic and metal organic structures and molecular clusters and demonstrate standard deviations from canonical CCSD(T) values of only 1.35 kJ/mol using a triple ζ basis set. We find that the incremental scheme is significantly more cost-effective than the canonical implementation even for relatively small systems and that the ease of parallelization makes it possible to perform high-level calculations on large systems in a few hours on inexpensive computers. We show that the approximations that make our approach widely applicable are significantly smaller than both the basis set incompleteness error and the intrinsic error of the CCSD(T) method, and we further demonstrate that incremental energies can be reliably used in extrapolation schemes to obtain near complete basis set limit CCSD(T) reaction energies for large systems.

Antenna Performance Influenced by the Finite Extent and Conductivity of Ground Planes: A Collection of Reprints

Science.gov (United States)

1990-09-01

paper by W.D. Westfall ’Prediction of VLF diurnal phase changes and solar flare effect’, J. Geophys. Res., Vol. 67, No. 2, 916-917, Feb. 1962. B-11 I...tunnel non-uniformities in leaky feeder communication systems, IEEE Trans., Vol. AP-27, No. 4, pp. 560-564, July, 1979. 666 Book review of NikoZa Tesla ...probing of roof structures in coal wines, Radio Science, Vol. 15,%o. 6, 1105-1108, Nov. - Dec., 1980. (Sumuj7 of Mofiche article), Paper is available on

Network integration modelling of feeder and BRT(bus rapid transit) to reduce the usage of private vehicles in Palembang’s suburban area

Science.gov (United States)

Nur'afalia, D.; Afifa, F.; Rubianto, L.; Handayeni, K. D. M. E.

2018-01-01

The aim of this research is to determine the optimal feeder network route that integrates with BRT (Bus Rapid Transit). Palembang, a high growing population city with unresolved transportation demand sector. BRT as main public transportation could not fulfill people’s demand in transportation, especially in Alang-Alang Lebar sub-district. As an impact, the usage of private vehicles increases along the movement toward the city center. The concept of Network Integration that integrates feeder network with BRT is expected to be a solution to suppress the rate of private vehicles’ usage and to improve public transportation service, so that the use of BRT will be increased in the suburban area of Palembang. The method used to identifying the optimal route using Route Analysis method is route analysis using Tranetsim 0.4. The best route is obtained based on 156 movement samples. The result is 58,7% from 199 mobility’s potency of private vehicle usage’s can be reduced if there is a feeder network’s route in Alang-Alang Lebar’s sub-district. From the result, the existance of integration between feeder network and BRT is potential enough to reduce the usage of private vehicles and supports the sustainability of transportation mobility in Palembang City.

Evaluation of the effect of radiation levels and dose rates in irradiation of murine fibroblasts used as a feeder layer in the culture of human keratinocytes

International Nuclear Information System (INIS)

Yoshito, Daniele; Almeida, Tiago L.; Santin, Stefany Plumeri; Somessari, Elizabeth S.R.; Silveira, Carlos G. da; Mathor, Monica B.; Altran, Silvana C.; Isaac, Cesar

2009-01-01

In 1975, Rheinwald and Green published an effective methodology for obtaining and cultivating human keratinocytes. This methodology consisted of seeding keratinocytes onto a feeder layer composed of lineage 3T3 murine fibroblasts, the proliferation rate of which is then controlled through the action of ionizing radiation. The presence of the feeder layer encourages the development of keratinocyte colonies and their propagation in similar cultures, becoming possible several clinical applications as skin substitutes or wound dressings in situations such as post burn extensive skin loss and other skin disorders. However, good development of these keratinocytes depends on a high quality feeder layer among other factors. In the present work, we evaluated the relationship between radiation levels and dose rates applied to fibroblasts used in construction of feeder layers and the radiation effect on keratinocytes colonies forming efficiency. Results indicate 3T3 lineage murine fibroblasts irradiated with doses varying between 60 and 100 Gy can be used as a feeder layer immediately after irradiation or storage of the irradiated cells in suspension at 4 g C for 24 hours with similar results. The exception is when the irradiation dose rate is 2.75 Gyh -1 ; in this case, results suggested that the fibroblasts should be used immediately after irradiation. (author)

Análisis mecánico por elementos finitos de una antena UHF en la órbita de Marte

OpenAIRE

Moreno García, Carlos

2015-01-01

El proyecto desarrolla el diseño mecánico de una antena helicoidal en banda UHF que será parte de un satélite cuyo destino final será Marte. Los principales objetivos de la misión son: Buscar trazas o evidencia de metano y otros gases atmosféricos que podrían manifestar signos de procesos biológicos o geológicos activos, es decir, buscar indicios de vida pasada en Marte Poner a prueba la tecnología necesaria para posteriores misiones europeas a Marte. El proyecto se centrará en la...

Nitrogen fixed by cyanobacteria is utilized by deposit-feeders.

Science.gov (United States)

Karlson, Agnes M L; Gorokhova, Elena; Elmgren, Ragnar

2014-01-01

Benthic communities below the photic zone depend for food on allochthonous organic matter derived from seasonal phytoplankton blooms. In the Baltic Sea, the spring diatom bloom is considered the most important input of organic matter, whereas the contribution of the summer bloom dominated by diazotrophic cyanobacteria is less understood. The possible increase in cyanobacteria blooms as a consequence of eutrophication and climate change calls for evaluation of cyanobacteria effects on benthic community functioning and productivity. Here, we examine utilization of cyanobacterial nitrogen by deposit-feeding benthic macrofauna following a cyanobacteria bloom at three stations during two consecutive years and link these changes to isotopic niche and variations in body condition (assayed as C:N ratio) of the animals. Since nitrogen-fixing cyanobacteria have δ(15)N close to -2‰, we expected the δ(15)N in the deposit-feeders to decrease after the bloom if their assimilation of cyanobacteria-derived nitrogen was substantial. We also expected the settled cyanobacteria with their associated microheterotrophic community and relatively high nitrogen content to increase the isotopic niche area, trophic diversity and dietary divergence between individuals (estimated as the nearest neighbour distance) in the benthic fauna after the bloom. The three surface-feeding species (Monoporeia affinis, Macoma balthica and Marenzelleria arctia) showed significantly lower δ(15)N values after the bloom, while the sub-surface feeder Pontoporeia femorata did not. The effect of the bloom on isotopic niche varied greatly between stations; populations which increased niche area after the bloom had better body condition than populations with reduced niche, regardless of species. Thus, cyanobacterial nitrogen is efficiently integrated into the benthic food webs in the Baltic, with likely consequences for their functioning, secondary production, transfer efficiency, trophic interactions, and

Nitrogen fixed by cyanobacteria is utilized by deposit-feeders.

Directory of Open Access Journals (Sweden)

Agnes M L Karlson

Full Text Available Benthic communities below the photic zone depend for food on allochthonous organic matter derived from seasonal phytoplankton blooms. In the Baltic Sea, the spring diatom bloom is considered the most important input of organic matter, whereas the contribution of the summer bloom dominated by diazotrophic cyanobacteria is less understood. The possible increase in cyanobacteria blooms as a consequence of eutrophication and climate change calls for evaluation of cyanobacteria effects on benthic community functioning and productivity. Here, we examine utilization of cyanobacterial nitrogen by deposit-feeding benthic macrofauna following a cyanobacteria bloom at three stations during two consecutive years and link these changes to isotopic niche and variations in body condition (assayed as C:N ratio of the animals. Since nitrogen-fixing cyanobacteria have δ(15N close to -2‰, we expected the δ(15N in the deposit-feeders to decrease after the bloom if their assimilation of cyanobacteria-derived nitrogen was substantial. We also expected the settled cyanobacteria with their associated microheterotrophic community and relatively high nitrogen content to increase the isotopic niche area, trophic diversity and dietary divergence between individuals (estimated as the nearest neighbour distance in the benthic fauna after the bloom. The three surface-feeding species (Monoporeia affinis, Macoma balthica and Marenzelleria arctia showed significantly lower δ(15N values after the bloom, while the sub-surface feeder Pontoporeia femorata did not. The effect of the bloom on isotopic niche varied greatly between stations; populations which increased niche area after the bloom had better body condition than populations with reduced niche, regardless of species. Thus, cyanobacterial nitrogen is efficiently integrated into the benthic food webs in the Baltic, with likely consequences for their functioning, secondary production, transfer efficiency, trophic

Optimal distribution feeder reconfiguration for increasing the penetration of plug-in electric vehicles and minimizing network costs

International Nuclear Information System (INIS)

Kavousi-Fard, Abdollah; Abbasi, Alireza; Rostami, Mohammad-Amin; Khosravi, Abbas

2015-01-01

Appearance of PEVs (Plug-in Electric Vehicles) in future transportation sector brings forward opportunities and challenges from grid perspective. Increased utilization of PEVs will result in problems such as greater total loss, unbalanced load factor, feeder congestion and voltage drop. PEVs are mobile energy storages dispersed all over the network with benefits to both owners and utilities in case of V2G (Vehicle-to-Grid) possibility. The intelligent bidirectional power flow between grid and large number of vehicles adds complexity to the system and requires operative tools to schedule V2G energy and subdue PEV impacts. In this paper, DFR (Distribution Feeder Reconfiguration) is utilized to optimally coordinate PEV operation in a stochastic framework. Uncertainty in PEVs characteristics can be due to several sources from location and time of grid connection to driving pattern and battery SoC (State-of-Charge). The proposed stochastic problem is solved with a self-adaptive evolutionary swarm algorithm based on SSO (Social Spider Optimization) algorithm. Numerical studies verify the efficacy of the proposed DFR to improve the system performance and optimal dispatch of V2G. - Highlights: • Consideration effect of PEVS on the distribution feeder reconfiguration. • Increasing the penetration of PEVS. • Introducing a new artificial optimization algorithm. • Modeling the uncertainty in network. • Investigating the degradation cost of batteries in V2G technology.

Cool Down Experiences with the SST-1 Helium Cryogenics System before and after Current Feeders System Modification

Science.gov (United States)

Patel, R.; Panchal, P.; Panchal, R.; Tank, J.; Mahesuriya, G.; Sonara, D.; Srikanth, G. L. N.; Garg, A.; Bairagi, N.; Christian, D.; Patel, K.; Shah, P.; Nimavat, H.; Sharma, R.; Patel, J. C.; Gupta, N. C.; Prasad, U.; Sharma, A. N.; Tanna, V. L.; Pradhan, S.

The SST-1 machine comprises a superconducting magnet system (SCMS), which includes TF and PF magnets. In order to charge the SCMS, we need superconducting current feeders consisting of SC feeders and vapor cooled current leads (VCCLs). We have installed all 10 (+/-) pairs of VCCLs for the TF and PF systems. While conducting initial engineering validation of the SST-1 machine, our prime objective was to produce circular plasma using only the TF system. During the SST-1 campaign I to VI, we have to stop the PF magnets cooling in order to get the cryo- stable conditions for current charging of the TF magnets system. In that case, the cooling of the PF current leads is not essential. It has been also observed that after aborting the PF system cooling, there was a limited experimental window of TF operation. Therefore, in the recent SST-1 campaign-VII, we removed the PF current leads (9 pairs) and kept only single (+/-) pair of the 10,000 A rated VCCLs to realize the charging of the TF system for the extended window of operation. We have observed a better cryogenic stability in the TF magnets after modifications in the CFS. In this paper, we report the comparison of the cool down performance for the SST-1 machine operation before and after modifications of the current feeders system.

A Frequency-Based Assignment Model under Day-to-Day Information Evolution of Oversaturated Conditions on a Feeder Bus Service

Directory of Open Access Journals (Sweden)

Silin Zhang

2017-02-01

Full Text Available Day-to-day information is increasingly being implemented in transit networks worldwide. Feeder bus service (FBS plays a vital role in a public transit network by providing feeder access to hubs and rails. As a feeder service, a space-time path for frequent passengers is decided by its dynamic strategy procedure, in which a day-to-day information self-learning mechanism is identified and analyzed from our survey data. We formulate a frequency-based assignment model considering day-to-day evolution under oversaturated conditions, which takes into account the residual capacity of bus and the comfort feelings of sitting or standing. The core of our proposed model is to allocate the passengers on each segment belonging to their own paths according to multi-utilities transformed from the time values and parametric demands, such as frequency, bus capacity, seat comfort, and stop layout. The assignment method, albeit general, allows us to formulate an equivalent optimization problem in terms of interaction between the FBS’ operation and frequent passengers’ rational behaviors. Finally, a real application case is generated to test the ability of the modeling framework capturing the theoretical consequents, serving the passengers’ dynamic externalities.

Surgical management of dural arteriovenous fistulas with transosseous arterial feeders involving the jugular bulb.

Science.gov (United States)

Tirakotai, W; Benes, L; Kappus, C; Sure, U; Farhoud, A; Bien, S; Bertalanffy, H

2007-01-01

Dural arteriovenous fistulas located in the vicinity of the jugular foramen are complex vascular malformations and belong to the most challenging skull base lesions to treat. The authors comprehensively analyze multiple features in a series of dural arteriovenous fistulas with transosseous arterial feeders involving the jugular bulb. Four patients who underwent surgery via the transcondylar approach to treat dural arteriovenous fistulas around the jugular foramen were retrospectively reviewed. Previously, endovascular treatment was attempted in all patients. The success of the surgical treatment was examined with postoperative angiography. Complete obliteration of the dural arteriovenous fistulas (DAVFs) was achieved in three patients, and significant flow reduction in one individual. All patients had a good postoperative outcome, and only one experienced mild hypoglossal nerve palsy. Despite extensive bone drilling, an occipitocervical fusion was necessary in only one patient with bilateral lesions. The use of an individually tailored transcondylar approach to treat dural arteriovenous fistulas at the region of the jugular foramen is most effective. This approach allows for complete obliteration of the connecting arterial feeders, and removal of bony structures containing pathological vessels.

Time-dependent resonant UHF CI approach for the photo-induced dynamics of the multi-electron system confined in 2D QD

Energy Technology Data Exchange (ETDEWEB)

Okunishi, Takuma; Clark, Richard; Takeda, Kyozaburo [Waseda University, Tokyo 169-8555 (Japan); Kusakabe, Kouichi [Osaka University, Osaka 560-8531 (Japan); Tomita, Norikazu [Yamagata University, Yamagata 960-8560 (Japan)

2013-12-04

We extend the static multi-reference description (resonant UHF) to the dynamic system in order to include the correlation effect over time, and simplify the TD Schrödinger equation (TD-CI) into a time-developed rate equation where the TD external field Ĥ′(t) is then incorporated directly in the Hamiltonian without any approximations. We apply this TD-CI method to the two-electron ground state of a 2D quantum dot (QD) under photon injection and study the resulting two-electron Rabi oscillation.

Leaky Integrate-and-Fire Neuron Circuit Based on Floating-Gate Integrator

Science.gov (United States)

Kornijcuk, Vladimir; Lim, Hyungkwang; Seok, Jun Yeong; Kim, Guhyun; Kim, Seong Keun; Kim, Inho; Choi, Byung Joon; Jeong, Doo Seok

2016-01-01

The artificial spiking neural network (SNN) is promising and has been brought to the notice of the theoretical neuroscience and neuromorphic engineering research communities. In this light, we propose a new type of artificial spiking neuron based on leaky integrate-and-fire (LIF) behavior. A distinctive feature of the proposed FG-LIF neuron is the use of a floating-gate (FG) integrator rather than a capacitor-based one. The relaxation time of the charge on the FG relies mainly on the tunnel barrier profile, e.g., barrier height and thickness (rather than the area). This opens up the possibility of large-scale integration of neurons. The circuit simulation results offered biologically plausible spiking activity (circuit was subject to possible types of noise, e.g., thermal noise and burst noise. The simulation results indicated remarkable distributional features of interspike intervals that are fitted to Gamma distribution functions, similar to biological neurons in the neocortex. PMID:27242416

Flow visualization study of two phase flow in a single bend outlet feeder pipe and horizontal annulus of outlet end-fitting of a CANDU reactor

International Nuclear Information System (INIS)

Supa-Amornkul, S.; Lister, D.H.; Steward, F.R.

2005-01-01

'Full text:' In CANDU-6 reactors, the pressurized high-temperature coolant flows through 380 fuel channels passing horizontally through the core. Each end of a fuel channel has a stainless steel annular end-fitting connected to a carbon steel feeder pipe. The outlet coolant, which is at 310 o C with up to 0.30 steam voidage, turns through 90 o as it passes from flow in the annular end-fitting to pipe flow in the feeder via a Grayloc connector. Since 1996, several CANDU stations have reported excessive corrosion of their outlet feeder pipes; especially between the first metre, which consisted of single or double bends. Early studies related the attack to the hydrodynamics of the coolant and verified that it was a type of flow accelerated corrosion. In order to understand the hydrodynamics of the coolant in the outlet feeders by flow-visualization, a full-scale transparent test section simulating the geometry and orientation of an outlet feeder bend with its upstream annular end-fitting were fabricated. The feeder consisted of a 54 mm inside diameter acrylic pipe with a 73 o bend, connecting to an acrylic simulation of a Grayloc flanged fitting and annular end-fitting. The annular end-fitting consisted of an inner pipe, 110 mm outer diameter, and an outer pipe, 150 mm inner diameter, both 190.7 cm long in length. The tests were performed with water and air at atmospheric pressure and room temperature. The maximum water volumetric flow rate was 19 L/s and the volume fraction of air varied from 0.05 to 0.56. The phase distributions within the feeder pipe and along the length of the annulus were investigated with a digital video recorder. Size, concentration and velocity of the air bubbles at particular locations were studied with a high-speed digital still camera and a high-speed digital video camera. Phase distributions and variations in bubble size with velocity were determined. Particular attention was paid to the flow pattern at the inside of the bend, where a CFD

Flow visualization study of two phase flow in a single bend outlet feeder pipe and horizontal annulus of outlet end-fitting of a CANDU reactor

Energy Technology Data Exchange (ETDEWEB)

Supa-Amornkul, S.; Lister, D.H.; Steward, F.R. [Univ. of New Brunswick, Fredericton, New Brunswick (Canada)]. E-mail: h796e@unb.ca; dlister@unb.ca; fsteward@unb.ca

2005-07-01

'Full text:' In CANDU-6 reactors, the pressurized high-temperature coolant flows through 380 fuel channels passing horizontally through the core. Each end of a fuel channel has a stainless steel annular end-fitting connected to a carbon steel feeder pipe. The outlet coolant, which is at 310{sup o}C with up to 0.30 steam voidage, turns through 90{sup o} as it passes from flow in the annular end-fitting to pipe flow in the feeder via a Grayloc connector. Since 1996, several CANDU stations have reported excessive corrosion of their outlet feeder pipes; especially between the first metre, which consisted of single or double bends. Early studies related the attack to the hydrodynamics of the coolant and verified that it was a type of flow accelerated corrosion. In order to understand the hydrodynamics of the coolant in the outlet feeders by flow-visualization, a full-scale transparent test section simulating the geometry and orientation of an outlet feeder bend with its upstream annular end-fitting were fabricated. The feeder consisted of a 54 mm inside diameter acrylic pipe with a 73{sup o} bend, connecting to an acrylic simulation of a Grayloc flanged fitting and annular end-fitting. The annular end-fitting consisted of an inner pipe, 110 mm outer diameter, and an outer pipe, 150 mm inner diameter, both 190.7 cm long in length. The tests were performed with water and air at atmospheric pressure and room temperature. The maximum water volumetric flow rate was 19 L/s and the volume fraction of air varied from 0.05 to 0.56. The phase distributions within the feeder pipe and along the length of the annulus were investigated with a digital video recorder. Size, concentration and velocity of the air bubbles at particular locations were studied with a high-speed digital still camera and a high-speed digital video camera. Phase distributions and variations in bubble size with velocity were determined. Particular attention was paid to the flow pattern at the inside

Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture

International Nuclear Information System (INIS)

Yoshito, Daniele

2011-01-01

For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

A Double-Resistive Active Power Filter System to Attenuate Harmonic Voltages of a Radial Power Distribution Feeder

DEFF Research Database (Denmark)

Sun, Xiaofeng; Han, Ruijing; Shen, Hong

2016-01-01

voltages. This paper proposes a double-resistive active power filter (D-RAPF) system consisting of a terminal-RAPF and an attenuation-RAPF for each individual harmonic. The terminal-RAPF operating as the characteristic impedance of the feeder is installed at the end bus to suppress harmonic propagation......Harmonic propagation between power-factor correction capacitors and system inductors seriously deteriorates power quality in a radial power distribution feeder. Installation of a resistive active power filter (RAPF) at the end bus only suppresses harmonic propagation, not attenuates harmonic...... at all harmonic frequencies. The attenuation-RAPF, whose control gain can be set according to the requirements of the harmonic voltage distortion limit, is installed at a specific position for each individual harmonic to attenuate the corresponding harmonic voltages. The D-RAPF system not only suppresses...

Power Hardware-in-the-Loop Evaluation of PV Inverter Grid Support on Hawaiian Electric Feeders: Preprint

Energy Technology Data Exchange (ETDEWEB)

Nelson, Austin; Prabakar, Kumaraguru; Nagarajan, Adarsh; Nepal, Shaili; Hoke, Anderson; Asano, Marc; Ueda, Reid; Ifuku, Earle

2017-05-08

As more grid-connected photovoltaic (PV) inverters become compliant with evolving interconnections requirements, there is increased interest from utilities in understanding how to best deploy advanced grid-support functions (GSF) in the field. One efficient and cost-effective method to examine such deployment options is to leverage power hardware-in-the-loop (PHIL) testing methods. Two Hawaiian Electric feeder models were converted to real-time models in the OPAL-RT real-time digital testing platform, and integrated with models of GSF capable PV inverters that were modeled from characterization test data. The integrated model was subsequently used in PHIL testing to evaluate the effects of different fixed power factor and volt-watt control settings on voltage regulation of the selected feeders. The results of this study were provided as inputs for field deployment and technical interconnection requirements for grid-connected PV inverters on the Hawaiian Islands.

Utilisation of symmetrical components in a communication-based protection for loop MV feeders with variable short-circuit power

DEFF Research Database (Denmark)

Ciontea, Catalin-Iosif; Bak, Claus Leth; Blaabjerg, Frede

2018-01-01

-circuit power is presented. It relies on utilisation of symmetrical components of the short-circuit currents and on communication between the protection relays. The proposed method addresses the Single Phase to Ground (SPG) faults occurring in directly grounded distribution networks, with focus on closed......Variability of the available short-circuit power also implies variation of the fault level, which can potentially cause several protection problems in the electric networks. In this paper, a novel protection method that is insensitive to the fault level changes caused by variable short......-loop Medium Voltage (MV) feeders. Case studies are presented, which demonstrate that the proposed protection scheme is capable of effectively detecting the SPG faults in closed-loop feeders with variable short-circuit power....

Design of a passive UHF RFID tag for the ISO18000-6C protocol

Energy Technology Data Exchange (ETDEWEB)

Wang Yao; Wen Guangjun; Mao Wei; He Yanli; Zhu Xueyong, E-mail: wangyao220597@yahoo.com.cn [RFIC Laboratory CICS, School of Communication and Information Engineering, University of Electronic Science and Technology of China, Chengdu 611731 (China)

2011-05-15

This paper presents a new fully integrated wide-range UHF passive RFID tag chip design that is compatible with the ISO18000-6C protocol. In order to reduce the die area, an ultra-low power CMOS voltage regulator without resistors and an area-efficient amplitude shift keying demodulator with a novel adaptive average generator are both adopted. A low power clock generator is designed to guarantee the accuracy of the clock under {+-}4%. As the clock gating technology is employed to reduce the power consumption of the baseband processor, the total power consumption of the tag is about 14 {mu}W with a sensitivity of -9.5 dBm. The detection distance can reach about 5 m under 4 W effective isotropic radiated power. The whole tag is fabricated in TSMC 0.18 {mu}m CMOS technology and the chip size is 880 x 880 {mu}m{sup 2}. (semiconductor integrated circuits)

Design of a passive UHF RFID tag for the ISO18000-6C protocol

International Nuclear Information System (INIS)

Wang Yao; Wen Guangjun; Mao Wei; He Yanli; Zhu Xueyong

2011-01-01

This paper presents a new fully integrated wide-range UHF passive RFID tag chip design that is compatible with the ISO18000-6C protocol. In order to reduce the die area, an ultra-low power CMOS voltage regulator without resistors and an area-efficient amplitude shift keying demodulator with a novel adaptive average generator are both adopted. A low power clock generator is designed to guarantee the accuracy of the clock under ±4%. As the clock gating technology is employed to reduce the power consumption of the baseband processor, the total power consumption of the tag is about 14 μW with a sensitivity of -9.5 dBm. The detection distance can reach about 5 m under 4 W effective isotropic radiated power. The whole tag is fabricated in TSMC 0.18 μm CMOS technology and the chip size is 880 x 880 μm 2 . (semiconductor integrated circuits)

Coplanar UHF RFID tag antenna with U-shaped inductively coupled feed for metallic applications.

Directory of Open Access Journals (Sweden)

Karrar Naji Salman

Full Text Available In this paper, we present a novel compact, coplanar, tag antenna design for metallic objects. Electrically small antenna has designed for a UHF RFID (860-960 MHz based on a proximity-coupled feed through. Furthermore, two symmetrical Via-loaded coplanar grounds fed by a U-shaped inductively coupled feed through an embedded transmission line. This configuration results in an antenna with dimensions of 31 × 19.5 × 3.065 mm3 at 915 MHz, and the total gain for the antenna is 0.12 dBi. The Via-loaded coplanar and U-shaped inductively coupled feeds allow the antenna to provide flexible tuning in terms of antenna impedance. In addition, a figure of merit is applied for the proposed tag antenna, and the results are presented. The read range is measured to be 4.2 m, which is very close to simulated values. This antenna measurement shows very good agreement with simulations.

Enhancing the power output of the VA-955 UHF-TV klystron

International Nuclear Information System (INIS)

Bowen, O.N.; Lawson, J.Q.

1977-01-01

The Varian VA-955 UHF-TV klystron is rated at 50 kW CW, and four of these klystrons were used to provide 200 kW of RF power for lower hybrid heating experiments on the ATC machine at 800 MHz. These proven, production-type tubes were wanted to generate more power for larger type machines, such as the PDX. Varian was asked whether the tubes were capable of higher-power operation in pulsed applications. They replied that they had no experimental data but felt that the tubes were capable of greatly enhanced performance under pulsed conditions. By using cathode modulation instead of modulating anode control of the klystron, and thus limiting the time that high voltage is applied to the cathode, it was shown that the tube is capable of an output power of 200 kW for tens of milliseconds compared to its normal CW rating of 50 kW. A description is given of the experimental results, the required modifications to the klystron and output transmission circuit, the details of operation of the regulating modulator used to perform the experiment. Upgrade kits are now being fabricated to allow 200 kW operation of the two 50 kW units which were lent to General Atomic for Doublet II experiments

A current-mode voltage regulator with an embedded sub-threshold reference for a passive UHF RFID transponder

Energy Technology Data Exchange (ETDEWEB)

Liu Zhongqi [Department of Electronic Engineering, Tsinghua University, Beijing 100084 (China); Zhang Chun; Li Yongming; Wang Zhihua, E-mail: liu-zq04@mails.tsinghua.edu.c [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

2010-06-15

This paper presents a current-mode voltage regulator for a passive UHF RFID transponder. The passive tag power is extracted from RF energy through the RF-to-DC rectifier. Due to huge variations of the incoming RF power, the rectifier output voltage should be regulated to achieve a stable power supply. By accurately controlling the current flowing into the load with an embedded sub-threshold reference, the regulated voltage varies in a range of 1-1.3 V from -20 to 80 {sup 0}C, and a bandwidth of about 100 kHz is achieved for a fast power recovery. The circuit is fabricated in UMC 0.18 {mu}m mixed-mode CMOS technology, and the current consumption is only 1 {mu}A. (semiconductor integrated circuits)

A current-mode voltage regulator with an embedded sub-threshold reference for a passive UHF RFID transponder

International Nuclear Information System (INIS)

Liu Zhongqi; Zhang Chun; Li Yongming; Wang Zhihua

2010-01-01

This paper presents a current-mode voltage regulator for a passive UHF RFID transponder. The passive tag power is extracted from RF energy through the RF-to-DC rectifier. Due to huge variations of the incoming RF power, the rectifier output voltage should be regulated to achieve a stable power supply. By accurately controlling the current flowing into the load with an embedded sub-threshold reference, the regulated voltage varies in a range of 1-1.3 V from -20 to 80 0 C, and a bandwidth of about 100 kHz is achieved for a fast power recovery. The circuit is fabricated in UMC 0.18 μm mixed-mode CMOS technology, and the current consumption is only 1 μA. (semiconductor integrated circuits)

Applicability of ANSYS ELBOW290 element for flexibility calculation of tight radius bends on feeder pipes in CANDU reactors

Energy Technology Data Exchange (ETDEWEB)

Zhang, X., E-mail: Xuan.Zhang@candu.com [Candu Energy Inc, Mississauga, ON (Canada)

2015-07-01

A curved pipe element, ELBOW290, became available in ANSYS 12. This element was developed based on a simplified shell theory, and maintains the ability to capture cross-sectional deformations of elbows. Numerical testing on the applicability of this element for the flexibility calculation of the tight radius bends in CANDU reactors is carried out to determine the usability of this element in completing stress analyses for feeder pipes. Comparisons are made between the ELBOW290 and the shell element for various feeder bend types found in domestic and overseas CANDU reactors. The comparisons show that the ELBOW290 element is suitable for calculating the flexibility of the tight radius bends. (author)

A voltage regulator system with dynamic bandwidth boosting for passive UHF RFID transponders

International Nuclear Information System (INIS)

Shen Jinpeng; Wang Xin'an; Liu Shan; Li Shoucheng; Ruan Zhengkun

2013-01-01

This paper presents a voltage regulator system for passive UHF RFID transponders, which contains a rectifier, a limiter, and a regulator. The rectifier achieves power by rectifying the incoming RF energy. Due to the huge variation of the rectified voltage, a limiter at the rectifier output is used to clamp the rectified voltage. In this paper, the design of a limiter circuit is discussed in detail, which can provide a stable limiting voltage with low sensitivity to temperature variation and process dispersion. The key aspect of the voltage regulator system is the dynamic bandwidth boosting in the regulator. By sensing the excess current that is bypassed in the limiter during periods of excess energy, the bias current as well as the bandwidth of the regulator are increased, the output supply voltage can recover quickly from line transients during the periods of no RF energy to a full blast of RF energy. This voltage regulator system is implemented in a 0.18 μm CMOS process. (semiconductor integrated circuits)

A UHF RFID system with on-chip-antenna tag for short range communication

International Nuclear Information System (INIS)

Peng Qi; Zhang Chun; Zhao Xijin; Wang Zhihua

2015-01-01

A UHF RF identification system based on the 0.18 μm CMOS process has been developed for short range and harsh size requirement applications, which is composed of a fully integrated tag and a special reader. The whole tag chip with the antenna takes up an area of 0.36 mm 2 , which is smaller than other reported tags with an on-chip antenna (OCA) using the standard CMOS process. A self-defined protocol is proposed to reduce the power consumption, and minimize the size of the tag. The specialized SOC reader system consists of the RF transceiver, digital baseband, MCU and host interface. Its power consumption is about 500 mW. Measurement results show that the system's reading range is 2 mm with 20 dBm reader output power. With an inductive antenna printed on a paper substrate around the OCA tag, the reading range can be extended from several centimeters to meters, depending on the shape and size of the inductive antenna. (paper)

Effects of an increasing filter feeder stock on larval abundance in the Oosterschelde estuary (SW Netherlands)

NARCIS (Netherlands)

Troost, Karin; Gelderman, Edzard; Kamermans, Pauline; Smaal, Aad C.; Wolff, Wim J.

Predation by adult bivalves oil bivalve larvae has been suggested to reduce larval abundance in areas with high bivalve filter-feeder biomass. Although the occurrence of larviphagy is well-studied in the laboratory, its effects in the field have scarcely been studied. We studied larviphagy at

Effects of an increasing filter feeder stock on larval abundance in the Oosterschelde estuary (SW Netherlands)

NARCIS (Netherlands)

Troost, K.; Gelderman, E.A.C.; Kamermans, P.; Smaal, A.C.; Wolff, W.

2009-01-01

Predation by adult bivalves on bivalve larvae has been suggested to reduce larval abundance in areas with high bivalve filter-feeder biomass. Although the occurrence of larviphagy is well-studied in the laboratory, its effects in the field have scarcely been studied. We studied larviphagy at

Experimental Study on Strain Reliability of Embroidered Passive UHF RFID Textile Tag Antennas and Interconnections

Directory of Open Access Journals (Sweden)

Xiaochen Chen

2017-01-01

Full Text Available We present embroidered antennas and interconnections in passive UHF RFID textile tags and test their strain reliability. Firstly, we fabricate tag antennas on two different stretchable fabric substrates by five different embroidery patterns and choose the most stretchable ones for testing. Next, the tag ICs are attached by sewing and gluing, and the tag reliability during repeated stretching cycles is evaluated through wireless measurements. Initially, the chosen tags achieve read ranges of 6–8 meters and can strain up to 140–150% of their original length. After 100 stretching cycles to 80% of their maximum strain, the read ranges of the tags with glued interconnections are similar to the initial values. In addition, also the read ranges of the tags with sewed interconnections are still more than 70%–85% of their initial values. However, some challenges with the reproducibility need to be solved next.

Differentiation of oligodendrocyte progenitor cells from dissociated monolayer and feeder-free cultured pluripotent stem cells.

Science.gov (United States)

Yamashita, Tomoko; Miyamoto, Yuki; Bando, Yoshio; Ono, Takashi; Kobayashi, Sakurako; Doi, Ayano; Araki, Toshihiro; Kato, Yosuke; Shirakawa, Takayuki; Suzuki, Yutaka; Yamauchi, Junji; Yoshida, Shigetaka; Sato, Naoya

2017-01-01

Oligodendrocytes myelinate axons and form myelin sheaths in the central nervous system. The development of therapies for demyelinating diseases, including multiple sclerosis and leukodystrophies, is a challenge because the pathogenic mechanisms of disease remain poorly understood. Primate pluripotent stem cell-derived oligodendrocytes are expected to help elucidate the molecular pathogenesis of these diseases. Oligodendrocytes have been successfully differentiated from human pluripotent stem cells. However, it is challenging to prepare large amounts of oligodendrocytes over a short amount of time because of manipulation difficulties under conventional primate pluripotent stem cell culture methods. We developed a proprietary dissociated monolayer and feeder-free culture system to handle pluripotent stem cell cultures. Because the dissociated monolayer and feeder-free culture system improves the quality and growth of primate pluripotent stem cells, these cells could potentially be differentiated into any desired functional cells and consistently cultured in large-scale conditions. In the current study, oligodendrocyte progenitor cells and mature oligodendrocytes were generated within three months from monkey embryonic stem cells. The embryonic stem cell-derived oligodendrocytes exhibited in vitro myelinogenic potency with rat dorsal root ganglion neurons. Additionally, the transplanted oligodendrocyte progenitor cells differentiated into myelin basic protein-positive mature oligodendrocytes in the mouse corpus callosum. This preparative method was used for human induced pluripotent stem cells, which were also successfully differentiated into oligodendrocyte progenitor cells and mature oligodendrocytes that were capable of myelinating rat dorsal root ganglion neurons. Moreover, it was possible to freeze, thaw, and successfully re-culture the differentiating cells. These results showed that embryonic stem cells and human induced pluripotent stem cells maintained in a

Effect of Antimicrobial Dosage Regimen on Salmonella and Escherichia coli Isolates from Feeder Swine▿

Science.gov (United States)

Wagner, Bruce A.; Straw, Barbara E.; Fedorka-Cray, Paula J.; Dargatz, David A.

2008-01-01

A body of evidence exists that suggests that antimicrobial use in food animals leads to resistance in both pathogenic and commensal bacteria. This study focused on the impact of three different antimicrobial regimes (low-level continuous, pulse, and no antimicrobial) for two antimicrobials (chlortetracycline and tylosin) on the presence of Salmonella spp. and on the prevalence of antimicrobial resistance of both Salmonella spp. and nonspecific Escherichia coli in fecal samples from feeder swine. The prevalence of fecal samples positive for Salmonella spp. significantly decreased between the samples taken at feeder placement compared to samples taken when the animals were close to market weight. Differences in resistance of Salmonella spp. did not appear to be influenced by dosing treatment including the control. Analysis of antimicrobial resistance examining both susceptibility and resistance, as well as MIC outcomes, demonstrated that only resistance to cephalothin increased in E. coli under the pulse chlortetracycline treatment. These results suggest that the dosing regimes examined in this study did not lead to an increase in either the prevalence of Salmonella spp. or the prevalence of antimicrobial resistance in isolates of Salmonella spp. or E. coli. PMID:18223115

Enhanced Particle Swarm Optimization-Based Feeder Reconfiguration Considering Uncertain Large Photovoltaic Powers and Demands

Directory of Open Access Journals (Sweden)

Ying-Yi Hong

2014-01-01

Full Text Available The Kyoto protocol recommended that industrialized countries limit their green gas emissions in 2012 to 5.2% below 1990 levels. Photovoltaic (PV arrays provide clear and sustainable renewable energy to electric power systems. Solar PV arrays can be installed in distribution systems of rural and urban areas, as opposed to wind-turbine generators, which cause noise in surrounding environments. However, a large PV array (several MW may incur several operation problems, for example, low power quality and reverse power. This work presents a novel method to reconfigure the distribution feeders in order to prevent the injection of reverse power into a substation connected to the transmission level. Moreover, a two-stage algorithm is developed, in which the uncertain bus loads and PV powers are clustered by fuzzy-c-means to gain representative scenarios; optimal reconfiguration is then achieved by a novel mean-variance-based particle swarm optimization. The system loss is minimized while the operational constraints, including reverse power and voltage variation, are satisfied due to the optimal feeder reconfiguration. Simulation results obtained from a 70-bus distribution system with 4 large PV arrays validate the proposed method.

Power Hardware-in-the-Loop Evaluation of PV Inverter Grid Support on Hawaiian Electric Feeders

Energy Technology Data Exchange (ETDEWEB)

Nelson, Austin A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Prabakar, Kumaraguru [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nagarajan, Adarsh [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nepal, Shaili [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hoke, Anderson F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Asano, Marc [Hawaiian Electric Company; Ueda, Reid [Hawaiian Electric Company; Ifuku, Earle [Hawaiian Electric Company

2017-10-03

As more grid-connected photovoltaic (PV) inverters become compliant with evolving interconnections requirements, there is increased interest from utilities in understanding how to best deploy advanced grid-support functions (GSF) in the field. One efficient and cost-effective method to examine such deployment options is to leverage power hardware-in-the-loop (PHIL) testing methods, which combine the fidelity of hardware tests with the flexibility of computer simulation. This paper summarizes a study wherein two Hawaiian Electric feeder models were converted to real-time models using an OPAL-RT real-time digital testing platform, and integrated with models of GSF capable PV inverters based on characterization test data. The integrated model was subsequently used in PHIL testing to evaluate the effects of different fixed power factor and volt-watt control settings on voltage regulation of the selected feeders using physical inverters. Selected results are presented in this paper, and complete results of this study were provided as inputs for field deployment and technical interconnection requirements for grid-connected PV inverters on the Hawaiian Islands.

Stability-index based method for optimal Var planning in distribution feeders

International Nuclear Information System (INIS)

Hamouda, Abdellatif; Zehar, Khaled

2011-01-01

Research highlights: → Optimal Var planning is modelled using heuristic methods. → Capacitor sizes and location are determined by a two stage method. → Capacitor locations are determined using nodes stability-indices. → Their sizes are calculated subject to a new constraint on the branches reactive currents. → The solution is fast and leads to better results without over compensation. -- Abstract: The problem of the reactive energy optimal planning can be solved in a fast and efficient way using heuristic techniques. The latter reduce the number of the control variables to be determined and lead to a near global optimal solution. The capacitor appropriate locations are firstly determined by decisive indices then, their optimal sizes are calculated. In this paper a stability-index based method is presented. The nodes stability-indices are calculated for identifying the most sensitive nodes to be candidate for receiving near optimal standard capacitors that, reduce the feeder power losses, improve the voltage profile and maximise the economic saving (objective function). In this multi-objective optimisation problem, the commonly used voltage constraint is substituted by a new constraint on the branch reactive currents. This new constraint, allows overcoming the over compensation phenomenon by setting positive branch reactive currents. The solution is further improved by regulating the source node voltage. The proposed approach has been tested on several feeder examples and its effectiveness has been demonstrated through comparative studies. The obtained results have shown that the proposed approach leads to a promising and feasible solution.

Stability-index based method for optimal Var planning in distribution feeders

Energy Technology Data Exchange (ETDEWEB)

Hamouda, Abdellatif, E-mail: a_hamouda1@yahoo.f [QUERE Laboratory, Optics and Mechanics Institut, University Ferhat Abbas, Setif 19000 (Algeria); Zehar, Khaled [QUERE Laboratory, Department of Electrical and Electronics Engineering, University of Bahrain, Isa Town (Bahrain)

2011-05-15

Research highlights: {yields} Optimal Var planning is modelled using heuristic methods. {yields} Capacitor sizes and location are determined by a two stage method. {yields} Capacitor locations are determined using nodes stability-indices. {yields} Their sizes are calculated subject to a new constraint on the branches reactive currents. {yields} The solution is fast and leads to better results without over compensation. -- Abstract: The problem of the reactive energy optimal planning can be solved in a fast and efficient way using heuristic techniques. The latter reduce the number of the control variables to be determined and lead to a near global optimal solution. The capacitor appropriate locations are firstly determined by decisive indices then, their optimal sizes are calculated. In this paper a stability-index based method is presented. The nodes stability-indices are calculated for identifying the most sensitive nodes to be candidate for receiving near optimal standard capacitors that, reduce the feeder power losses, improve the voltage profile and maximise the economic saving (objective function). In this multi-objective optimisation problem, the commonly used voltage constraint is substituted by a new constraint on the branch reactive currents. This new constraint, allows overcoming the over compensation phenomenon by setting positive branch reactive currents. The solution is further improved by regulating the source node voltage. The proposed approach has been tested on several feeder examples and its effectiveness has been demonstrated through comparative studies. The obtained results have shown that the proposed approach leads to a promising and feasible solution.

47 CFR 25.147 - Licensing provision for NGSO MSS feeder downlinks in the band 6700-6875 MHz.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Licensing provision for NGSO MSS feeder downlinks in the band 6700-6875 MHz. 25.147 Section 25.147 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space...

Auto- and Crosscorrelograms for the Spike Response of Leaky Integrate-and-Fire Neurons with Slow Synapses

International Nuclear Information System (INIS)

Moreno-Bote, Ruben; Parga, Nestor

2006-01-01

An analytical description of the response properties of simple but realistic neuron models in the presence of noise is still lacking. We determine completely up to the second order the firing statistics of a single and a pair of leaky integrate-and-fire neurons receiving some common slowly filtered white noise. In particular, the auto- and cross-correlation functions of the output spike trains of pairs of cells are obtained from an improvement of the adiabatic approximation introduced previously by Moreno-Bote and Parga [Phys. Rev. Lett. 92, 028102 (2004)]. These two functions define the firing variability and firing synchronization between neurons, and are of much importance for understanding neuron communication

The fluid dynamics of Balanus glandula barnacles: Adaptations to sheltered and exposed habitats.

Science.gov (United States)

Vo, Maureen; Mehrabian, Sasan; Villalpando, Fernando; Etienne, Stephane; Pelletier, Dominique; Cameron, Christopher B

2018-04-11

Suspension feeders use a wide range of appendages to capture particles from the surrounding fluid. Their functioning, either as a paddle or a sieve, depends on the leakiness, or amount of fluid that passes through the gaps between the appendages. Balanus glandula is the most common species of barnacle distributed along the Pacific coast of North America. It shows a strong phenotypic response to water flow velocity. Individuals from exposed, high flow sites have short and robust cirral filters, whereas those from sheltered, low velocity sites have long, spindly appendages. Computational fluid dynamics (CFD) simulations of these two ecophenotypes were done using a finite volume method. Leakiness was determined by simulating flow velocity fields at increasing Reynolds numbers, results that have been unattainable at higher velocities by observation. CFD also allowed us to characterize flow in hard to see regions of the feeding legs (rami). Laser-illumination experiments were performed at low to medium flow velocities in a flume tank and corroborated results from CFD. Barnacle filters from a sheltered site become completely leaky at Re=2.24(0.16m/s), well above the maximum habitat velocity, suggesting that this ecophenotype is not mechanically optimized for feeding. Barnacles from exposed environments become fully leaky within the range of habitat velocities Re=3.50(0.18m/s). Our CFD results revealed that the drag force on exposed barnacles feeding appendages are the same as the sheltered barnacles feeding appendages despite their shape difference and spacing ratio. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Andes hantavirus NSs protein is expressed from the viral small mRNA by a leaky scanning mechanism.

Science.gov (United States)

Vera-Otarola, Jorge; Solis, Loretto; Soto-Rifo, Ricardo; Ricci, Emiliano P; Pino, Karla; Tischler, Nicole D; Ohlmann, Théophile; Darlix, Jean-Luc; López-Lastra, Marcelo

2012-02-01

The small mRNA (SmRNA) of all Bunyaviridae encodes the nucleocapsid (N) protein. In 4 out of 5 genera in the Bunyaviridae, the smRNA encodes an additional nonstructural protein denominated NSs. In this study, we show that Andes hantavirus (ANDV) SmRNA encodes an NSs protein. Data show that the NSs protein is expressed in the context of an ANDV infection. Additionally, our results suggest that translation initiation from the NSs initiation codon is mediated by ribosomal subunits that have bypassed the upstream N protein initiation codon through a leaky scanning mechanism.

Improvement of the auto wire feeder machine in a de-soldering process

Directory of Open Access Journals (Sweden)

Niramon Nonkhukhetkhong

2016-10-01

Full Text Available This paper presents the methodology of the de-soldering process for rework of disk drive Head Stack Assembly (HSA units. The auto wire feeder is a machine that generates Tin (Sn on the product. This machine was determined to be one of the major sources of excess Sn on the HSA. The defect rate due to excess Sn is more than 30%, which leads to increased processing time and cost to perform additional cleaning steps. From process analysis, the major causes of excess Sn are as follows: 1 The machine cannot cut the wire all the way into the flux core area; 2 The sizes and types of soldering irons are not appropriate for the unit parts; and, 3 There are variations introduced into the de-soldering process by the workforce. This paper proposes a methodology to address all three of these causes. First, the auto wire feeder machine in the de-solder process will be adjusted in order to cut wires into flux core. Second, the types of equipment and material used in de-soldering will be optimized. Finally, a new standard method for operators, which can be controlled more easily, will be developed in order to reduce defects due to workforce related variation. After these process controls and machine adjustments were implemented, the overall Sn related problems were significantly improved. Sn contamination was reduced by 41% and cycle time was reduced by an average of 15 seconds.

Wearable Passive E-Textile UHF RFID Tag Based on a Slotted Patch Antenna with Sewn Ground and Microchip Interconnections

Directory of Open Access Journals (Sweden)

Johanna Virkki

2017-01-01

Full Text Available We present a wearable passive UHF RFID tag based on a slotted patch antenna comprising only textile materials (e-textile, textile substrate, and conductive yearn. As a novel manufacturing approach, we realize the patch-to-ground and antenna-to-IC interfaces using only conductive thread and a sewing machine. We outline the electromagnetic optimization of the antenna for body-worn operation through simulations and present a performance comparison between the e-textile tag and a tag produced using regular electronics materials and methods. The measured results show that the textile tag achieves the electrical performance required in practical applications and that the slotted patch type antenna provides stable electromagnetic performance in different body-worn configurations.

Short communication: Milk meal pattern of dairy calves is affected by computer-controlled milk feeder set-up

DEFF Research Database (Denmark)

Jensen, Margit Bak

2009-01-01

for a minimum of 2 and 4 portions, respectively, whereas low-fed calves ingested their milk in 2.4 and 4.4 meals for a minimum of 2 and 4 portions, respectively. Calves on a high milk allowance had fewer milk meals over time, whereas calves on a low milk allowance had the same number of milk meals throughout...... milk portions, whereas the other half could ingest the milk in 4 or more daily portions. Data were collected during 3 successive 14-d periods, the first period starting the day after introduction to the feeder at minimum 12 d of age. High-fed calves ingested their milk in 4.0 and 4.9 meals....... Thus, the development from small and frequent milk meals to fewer and larger meals reported by studies of natural suckling was also found among high-fed calves on a computer-controlled milk feeder. Irrespectively of minimum number of milk portions, the low-fed calves had more unrewarded visits...

Design of planar electron gun for UHF range, CW power inductive output tube

International Nuclear Information System (INIS)

Kaushik, Meenu; Joshi, L.M.

2015-01-01

Inductive Output Tube (lOT) is an amplifier which is now-a-days in demand for scientific applications. For every vacuum tube, electron gun is an important part and in fact considered as the heart of the tube. Hence, designing of this component is very crucial for efficient operation of the device throughout its lifetime. This paper is all about the electromagnetic (EM) design of planar electron gun of 40 kV, 3.5 A beam voltage and beam current respectively, for a 100 kW CW power lOT operating in UHF range. The design considerations and basic equations involved in its design are included in the paper. The gun structure has been optimized for getting the desired beam characteristics. The simulation results including the beam profile along with the beam current are shown using two commercial codes namely TRAK and MAGIC code. Planar shape of electron beam reduces space charge forces in the beam itself and consequently beam energy spread for a given current. The magnetic focusing of planar beam is easier comparative to spherical beam hence, this structure has been adopted for this particular device design. (author)

A look at one of the world`s largest apron feeder drives - Alberta Oil Sands Project

Energy Technology Data Exchange (ETDEWEB)

Persson, O. [Hagglunds Drives Canada Inc., Vancouver, BC (Canada)

1999-10-01

Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world`s largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

Handling system for nuclear fuel cans to a fuel pellet feeder

International Nuclear Information System (INIS)

Vere, B.; Mathevon, P.

1985-01-01

The handling system comprises a first array of conveyors which takes a batch of casings from a delivery rack, alters the spacing between the casings, and delivers them to a vibrating table feeder, a second array of conveyors which readjusts the spacing between casing to its initial value and transfers the casings to a removal rack, and automatic and synchronized control means for ensuring the displacements of casings always in the same direction. The increase of spacing between casings can be used, before feeding, to allow them to be weighed one after the other, and after feeding, for cleaning the end part of fuel cans [fr

Practice on Protection and Improvement of Withstand Voltage Weighing Belt Coal Feeder%耐压称重式皮带给煤机保护改进实践

Institute of Scientific and Technical Information of China (English)

王良

2016-01-01

This paper introduces the traits of withstand voltage weighing belt coal feeder. According to the modification and practice of parameters of the frequency converter, when there is a malfunction, the automatic recovery of the frequency converter of coal feeder can be achieved. The reliability of the coal feeder ’s operation will be improved, and the effects of the accident power supply perturbation on the coal feeder can be eliminated. Eventually, the safety and stability of the boilers can be guaranteed.%文章介绍了耐压称重式皮带给煤机的特性，通过对变频器参数修改实践，实现给煤机变频器故障保护自动恢复，提高给煤机运行的可靠性，消除电源意外扰动对给煤机的影响，保障锅炉安全持续稳定运行。

Neonatal Gene Therapy for Hemophilia B by a Novel Adenovirus Vector Showing Reduced Leaky Expression of Viral Genes.

Science.gov (United States)

Iizuka, Shunsuke; Sakurai, Fuminori; Tachibana, Masashi; Ohashi, Kazuo; Mizuguchi, Hiroyuki

2017-09-15

Gene therapy during neonatal and infant stages is a promising approach for hemophilia B, a congenital disorder caused by deficiency of blood coagulation factor IX (FIX). An adenovirus (Ad) vector has high potential for use in neonatal or infant gene therapy for hemophilia B due to its superior transduction properties; however, leaky expression of Ad genes often reduces the transduction efficiencies by Ad protein-mediated tissue damage. Here, we used a novel Ad vector, Ad-E4-122aT, which exhibits a reduction in the leaky expression of Ad genes in liver, in gene therapy studies for neonatal hemophilia B mice. Ad-E4-122aT exhibited significantly higher transduction efficiencies than a conventional Ad vector in neonatal mice. In neonatal hemophilia B mice, a single neonatal injection of Ad-E4-122aT expressing human FIX (hFIX) (Ad-E4-122aT-AHAFIX) maintained more than 6% of the normal plasma hFIX activity levels for approximately 100 days. Sequential administration of Ad-E4-122aT-AHAFIX resulted in more than 100% of the plasma hFIX activity levels for more than 100 days and rescued the bleeding phenotypes of hemophilia B mice. In addition, immunotolerance to hFIX was induced by Ad-E4-122aT-AHAFIX administration in neonatal hemophilia B mice. These results indicated that Ad-E4-122aT is a promising gene delivery vector for neonatal or infant gene therapy for hemophilia B.

A new hybrid evolutionary algorithm based on new fuzzy adaptive PSO and NM algorithms for Distribution Feeder Reconfiguration

International Nuclear Information System (INIS)

Niknam, Taher; Azadfarsani, Ehsan; Jabbari, Masoud

2012-01-01

Highlights: ► Network reconfiguration is a very important way to save the electrical energy. ► This paper proposes a new algorithm to solve the DFR. ► The algorithm combines NFAPSO with NM. ► The proposed algorithm is tested on two distribution test feeders. - Abstract: Network reconfiguration for loss reduction in distribution system is a very important way to save the electrical energy. This paper proposes a new hybrid evolutionary algorithm to solve the Distribution Feeder Reconfiguration problem (DFR). The algorithm is based on combination of a New Fuzzy Adaptive Particle Swarm Optimization (NFAPSO) and Nelder–Mead simplex search method (NM) called NFAPSO–NM. In the proposed algorithm, a new fuzzy adaptive particle swarm optimization includes two parts. The first part is Fuzzy Adaptive Binary Particle Swarm Optimization (FABPSO) that determines the status of tie switches (open or close) and second part is Fuzzy Adaptive Discrete Particle Swarm Optimization (FADPSO) that determines the sectionalizing switch number. In other side, due to the results of binary PSO(BPSO) and discrete PSO(DPSO) algorithms highly depends on the values of their parameters such as the inertia weight and learning factors, a fuzzy system is employed to adaptively adjust the parameters during the search process. Moreover, the Nelder–Mead simplex search method is combined with the NFAPSO algorithm to improve its performance. Finally, the proposed algorithm is tested on two distribution test feeders. The results of simulation show that the proposed method is very powerful and guarantees to obtain the global optimization.

Feeder-cell-independent culture of the pig-embryonic-stem-cell-derived exocrine pancreatic cell line, PICM-31

Science.gov (United States)

The adaptation to feeder-independent growth of a pig embryonic stem cell-derived pancreatic cell line is described. The parental PICM-31 cell line, previously characterized as an exocrine pancreas cell line, was colony-cloned two times in succession resulting in the subclonal cell line, PICM-31A1. P...

Radiation-Pressure Acceleration of Ion Beams from Nanofoil Targets: The Leaky Light-Sail Regime

International Nuclear Information System (INIS)

Qiao, B.; Zepf, M.; Borghesi, M.; Dromey, B.; Geissler, M.; Karmakar, A.; Gibbon, P.

2010-01-01

A new ion radiation-pressure acceleration regime, the 'leaky light sail', is proposed which uses sub-skin-depth nanometer foils irradiated by circularly polarized laser pulses. In the regime, the foil is partially transparent, continuously leaking electrons out along with the transmitted laser field. This feature can be exploited by a multispecies nanofoil configuration to stabilize the acceleration of the light ion component, supplementing the latter with an excess of electrons leaked from those associated with the heavy ions to avoid Coulomb explosion. It is shown by 2D particle-in-cell simulations that a monoenergetic proton beam with energy 18 MeV is produced by circularly polarized lasers at intensities of just 10 19 W/cm 2 . 100 MeV proton beams are obtained by increasing the intensities to 2x10 20 W/cm 2 .

Radiation-pressure acceleration of ion beams from nanofoil targets: the leaky light-sail regime.

Science.gov (United States)

Qiao, B; Zepf, M; Borghesi, M; Dromey, B; Geissler, M; Karmakar, A; Gibbon, P

2010-10-08

A new ion radiation-pressure acceleration regime, the "leaky light sail," is proposed which uses sub-skin-depth nanometer foils irradiated by circularly polarized laser pulses. In the regime, the foil is partially transparent, continuously leaking electrons out along with the transmitted laser field. This feature can be exploited by a multispecies nanofoil configuration to stabilize the acceleration of the light ion component, supplementing the latter with an excess of electrons leaked from those associated with the heavy ions to avoid Coulomb explosion. It is shown by 2D particle-in-cell simulations that a monoenergetic proton beam with energy 18 MeV is produced by circularly polarized lasers at intensities of just 10¹⁹  W/cm². 100 MeV proton beams are obtained by increasing the intensities to 2 × 10²⁰  W/cm².

Effects of Home Energy Management Systems on Distribution Utilities and Feeders Under Various Market Structure; NREL (National Renewable Energy Laboratory)

Energy Technology Data Exchange (ETDEWEB)

Ruth, M.; Pratt, A.; Lunacek, M.; Mittal, S.; Wu, H.; Jones, W.

2015-06-15

The combination of distributed energy resources (DER) and retail tariff structures to provide benefits to both utility consumers and the utilities is not well understood. To improve understanding, an Integrated Energy System Model (IESM) is being developed to simulate the physical and economic aspects of DER technologies, the buildings where they reside, and feeders servicing them. The IESM was used to simulate 20 houses with home energy management systems on a single feeder under a time-of-use (TOU) tariff to estimate economic and physical impacts on both the households and the distribution utilities. Home energy management systems (HEMS) reduce consumers’ electric bills by precooling houses in the hours before peak electricity pricing. Utilization of HEMS reduce peak loads during high price hours but shifts it to hours with off-peak and shoulder prices, resulting in a higher peak load. used to simulate 20 houses with home energy management systems on a single feeder under a time-of-use (TOU) tariff to estimate economic and physical impacts on both the households and the distribution utilities. Home energy management systems (HEMS) reduce consumers’ electric bills by precooling houses in the hours before peak electricity pricing. Utilization of HEMS reduce peak loads during high price hours but shifts it to hours with off-peak and shoulder prices, resulting in a higher peak load.

Vertical velocity and turbulence aspects during Mistral events as observed by UHF wind profilers

Directory of Open Access Journals (Sweden)

J.-L. Caccia

2004-11-01

Full Text Available The general purpose of this paper is to experimentally study mesoscale dynamical aspects of the Mistral in the coastal area located at the exit of the Rhône-valley. The Mistral is a northerly low-level flow blowing in southern France along the Rhône-valley axis, located between the French Alps and the Massif Central, towards the Mediterranean Sea. The experimental data are obtained by UHF wind profilers deployed during two major field campaigns, MAP (Mesoscale Alpine Program in autumn 1999, and ESCOMPTE (Expérience sur Site pour COntraindre les Modèles de Pollution atmosphériques et de Transports d'Emission in summer 2001. Thanks to the use of the time evolution of the vertical profile of the horizontal wind vector, recent works have shown that the dynamics of the Mistral is highly dependent on the season because of the occurrence of specific synoptic patterns. In addition, during summer, thermal forcing leads to a combination of sea breeze with Mistral and weaker Mistral due to the enhanced friction while, during autumn, absence of convective turbulence leads to substantial acceleration as low-level jets are generated in the stably stratified planetary boundary layer. At the exit of the Rhône valley, the gap flow dynamics dominates, whereas at the lee of the Alps, the dynamics is driven by the relative contribution of "flow around" and "flow over" mechanisms, upstream of the Alps. This paper analyses vertical velocity and turbulence, i.e. turbulent dissipation rate, with data obtained by the same UHF wind profilers during the same Mistral events. In autumn, the motions are found to be globally and significantly subsident, which is coherent for a dry, cold and stable flow approaching the sea, and the turbulence is found to be of pure dynamical origin (wind shears and mountain/lee wave breaking, which is coherent with non-convective situations. In summer, due to the ground heating and to the interactions with thermal circulation, the

Vertical velocity and turbulence aspects during Mistral events as observed by UHF wind profilers

Science.gov (United States)

Caccia, J.; Guénard, V.; Benech, B.; Campistron, B.; Drobinski, P.

2004-11-01

The general purpose of this paper is to experimentally study mesoscale dynamical aspects of the Mistral in the coastal area located at the exit of the Rhône-valley. The Mistral is a northerly low-level flow blowing in southern France along the Rhône-valley axis, located between the French Alps and the Massif Central, towards the Mediterranean Sea. The experimental data are obtained by UHF wind profilers deployed during two major field campaigns, MAP (Mesoscale Alpine Program) in autumn 1999, and ESCOMPTE (Expérience sur Site pour COntraindre les Modèles de Pollution atmosphériques et de Transports d'Emission) in summer 2001. Thanks to the use of the time evolution of the vertical profile of the horizontal wind vector, recent works have shown that the dynamics of the Mistral is highly dependent on the season because of the occurrence of specific synoptic patterns. In addition, during summer, thermal forcing leads to a combination of sea breeze with Mistral and weaker Mistral due to the enhanced friction while, during autumn, absence of convective turbulence leads to substantial acceleration as low-level jets are generated in the stably stratified planetary boundary layer. At the exit of the Rhône valley, the gap flow dynamics dominates, whereas at the lee of the Alps, the dynamics is driven by the relative contribution of "flow around" and "flow over" mechanisms, upstream of the Alps. This paper analyses vertical velocity and turbulence, i.e. turbulent dissipation rate, with data obtained by the same UHF wind profilers during the same Mistral events. In autumn, the motions are found to be globally and significantly subsident, which is coherent for a dry, cold and stable flow approaching the sea, and the turbulence is found to be of pure dynamical origin (wind shears and mountain/lee wave breaking), which is coherent with non-convective situations. In summer, due to the ground heating and to the interactions with thermal circulation, the vertical motions are

Vertical velocity and turbulence aspects during Mistral events as observed by UHF wind profilers

Energy Technology Data Exchange (ETDEWEB)

Caccia, J.L.; Guenard, V. [LSEET, CNRS/Univ. de Toulon, La Garde (France); Benech, B.; Campistron, B. [CRA/LA, CNRS/Obs. Midi-Pyrenees, Campistrous (France); Drobinski, P. [IPSL/SA, CNRS/Univ. de Paris VI, Paris (France)

2004-07-01

The general purpose of this paper is to experimentally study mesoscale dynamical aspects of the Mistral in the coastal area located at the exit of the Rhone-valley. The Mistral is a northerly low-level flow blowing in southern France along the Rhone-valley axis, located between the French Alps and the Massif Central, towards the Mediterranean Sea. The experimental data are obtained by UHF wind profilers deployed during two major field campaigns, MAP (mesoscale alpine program) in autumn 1999, and ESCOMPTE (Experience sur Site pour COntraindre les Modeles de Pollution atmospheriques et de Transports d'Emission) in summer 2001. Thanks to the use of the time evolution of the vertical profile of the horizontal wind vector, recent works have shown that the dynamics of the Mistral is highly dependent on the season because of the occurrence of specific synoptic patterns. In addition, during summer, thermal forcing leads to a combination of sea breeze with Mistral and weaker Mistral due to the enhanced friction while, during autumn, absence of convective turbulence leads to substantial acceleration as low-level jets are generated in the stably stratified planetary boundary layer. At the exit of the Rhone valley, the gap flow dynamics dominates, whereas at the lee of the Alps, the dynamics is driven by the relative contribution of ''flow around'' and ''flow over'' mechanisms, upstream of the Alps. This paper analyses vertical velocity and turbulence, i.e. turbulent dissipation rate, with data obtained by the same UHF wind profilers during the same Mistral events. In autumn, the motions are found to be globally and significantly subsident, which is coherent for a dry, cold and stable flow approaching the sea, and the turbulence is found to be of pure dynamical origin (wind shears and mountain/lee wave breaking), which is coherent with non-convective situations. In summer, due to the ground heating and to the interactions with

The Linehaul-Feeder Vehicle Routing Problem with Virtual Depots and Time Windows

Directory of Open Access Journals (Sweden)

Huey-Kuo Chen

2011-01-01

Full Text Available This paper addresses the linehaul-feeder vehicle routing problem with virtual depots and time windows (LFVRPTW. Small and large vehicles deliver services to customers within time constraints; small vehicles en route may reload commodities from either the physical depot or from the larger vehicle at a virtual depot before continuing onward. A two-stage solution heuristic involving Tabu search is proposed to solve this problem. The test results show that the LFVRPTW performs better than the vehicle routing problem with time windows in terms of both objective value and the number of small vehicles dispatched.

A single-cell and feeder-free culture system for monkey embryonic stem cells.

Science.gov (United States)

Ono, Takashi; Suzuki, Yutaka; Kato, Yosuke; Fujita, Risako; Araki, Toshihiro; Yamashita, Tomoko; Kato, Hidemasa; Torii, Ryuzo; Sato, Naoya

2014-01-01

Primate pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), hold great potential for research and application in regenerative medicine and drug discovery. To maximize primate PSC potential, a practical system is required for generating desired functional cells and reproducible differentiation techniques. Much progress regarding their culture systems has been reported to date; however, better methods would still be required for their practical use, particularly in industrial and clinical fields. Here we report a new single-cell and feeder-free culture system for primate PSCs, the key feature of which is an originally formulated serum-free medium containing FGF and activin. In this culture system, cynomolgus monkey ESCs can be passaged many times by single-cell dissociation with traditional trypsin treatment and can be propagated with a high proliferation rate as a monolayer without any feeder cells; further, typical PSC properties and genomic stability can be retained. In addition, it has been demonstrated that monkey ESCs maintained in the culture system can be used for various experiments such as in vitro differentiation and gene manipulation. Thus, compared with the conventional culture system, monkey ESCs grown in the aforementioned culture system can serve as a cell source with the following practical advantages: simple, stable, and easy cell maintenance; gene manipulation; cryopreservation; and desired differentiation. We propose that this culture system can serve as a reliable platform to prepare primate PSCs useful for future research and application.

Chimeras in leaky integrate-and-fire neural networks: effects of reflecting connectivities

Science.gov (United States)

Tsigkri-DeSmedt, Nefeli Dimitra; Hizanidis, Johanne; Schöll, Eckehard; Hövel, Philipp; Provata, Astero

2017-07-01

The effects of attracting-nonlocal and reflecting connectivity are investigated in coupled Leaky Integrate-and-Fire (LIF) elements, which model the exchange of electrical signals between neurons. Earlier investigations have demonstrated that repulsive-nonlocal and hierarchical network connectivity can induce complex synchronization patterns and chimera states in systems of coupled oscillators. In the LIF system we show that if the elements are nonlocally linked with positive diffusive coupling on a ring network, the system splits into a number of alternating domains. Half of these domains contain elements whose potential stays near the threshold and they are interrupted by active domains where the elements perform regular LIF oscillations. The active domains travel along the ring with constant velocity, depending on the system parameters. When we introduce reflecting coupling in LIF networks unexpected complex spatio-temporal structures arise. For relatively extensive ranges of parameter values, the system splits into two coexisting domains: one where all elements stay near the threshold and one where incoherent states develop, characterized by multi-leveled mean phase velocity profiles.

Reconstructing stimuli from the spike-times of leaky integrate and fire neurons

Directory of Open Access Journals (Sweden)

Sebastian eGerwinn

2011-02-01

Full Text Available Reconstructing stimuli from the spike-trains of neurons is an important approach for understanding the neural code. One of the difficulties associated with this task is that signals which are varying continuously in time are encoded into sequences of discrete events or spikes. An important problem is to determine how much information about the continuously varying stimulus can be extracted from the time-points at which spikes were observed, especially if these time-points are subject to some sort of randomness. For the special case of spike trains generated by leaky integrate and fire neurons, noise can be introduced by allowing variations in the threshold every time a spike is released. A simple decoding algorithm previously derived for the noiseless case can be extended to the stochastic case, but turns out to be biased. Here, we review a solution to this problem, by presenting a simple yet efficient algorithm which greatly reduces the bias, and therefore leads to better decoding performance in the stochastic case.

A look at one of the world's largest apron feeder drives - Alberta Oil Sands Project

Energy Technology Data Exchange (ETDEWEB)

Persson, O. (Hagglunds Drives Canada Inc., Vancouver, BC (Canada))

1999-01-01

Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world's largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

Creativity and sensory gating indexed by the P50: selective versus leaky sensory gating in divergent thinkers and creative achievers.

Science.gov (United States)

Zabelina, Darya L; O'Leary, Daniel; Pornpattananangkul, Narun; Nusslock, Robin; Beeman, Mark

2015-03-01

Creativity has previously been linked with atypical attention, but it is not clear what aspects of attention, or what types of creativity are associated. Here we investigated specific neural markers of a very early form of attention, namely sensory gating, indexed by the P50 ERP, and how it relates to two measures of creativity: divergent thinking and real-world creative achievement. Data from 84 participants revealed that divergent thinking (assessed with the Torrance Test of Creative Thinking) was associated with selective sensory gating, whereas real-world creative achievement was associated with "leaky" sensory gating, both in zero-order correlations and when controlling for academic test scores in a regression. Thus both creativity measures related to sensory gating, but in opposite directions. Additionally, divergent thinking and real-world creative achievement did not interact in predicting P50 sensory gating, suggesting that these two creativity measures orthogonally relate to P50 sensory gating. Finally, the ERP effect was specific to the P50 - neither divergent thinking nor creative achievement were related to later components, such as the N100 and P200. Overall results suggest that leaky sensory gating may help people integrate ideas that are outside of focus of attention, leading to creativity in the real world; whereas divergent thinking, measured by divergent thinking tests which emphasize numerous responses within a limited time, may require selective sensory processing more than previously thought. Copyright © 2015 Elsevier Ltd. All rights reserved.

In situ occupational and general public exposure to VHF/UHF transmission for air traffic communication

International Nuclear Information System (INIS)

Joseph, W.; Goeminne, F.; Verloock, L.; Vermeeren, G.; Martens, L.

2012-01-01

Occupational and general public exposure due to very high frequency (VHF)/ultra high frequency (UHF) transmission centres for verbal communication for air traffic control is investigated in situ for the first time. These systems are used for communication with aircraft, resulting in different human exposure from that of classical broadcasting. Measurement methods are proposed for the exposure assessment, and a measurement campaign is executed in three transmission centres. By investigating the temporal behaviour of the VHF signals for 6 d, a realistic worst-case duty cycle of 29 % is determined. Periods of high exposures corresponding with high aircraft traffic are from 7 a.m. to 1 p.m. and in the evening. All measured electric field values satisfy the International Commission on Non-ionizing Radiation Protection guidelines. Fields vary from 0.2 to 21.1 V m -1 for occupational exposure and from 0.007 to 8.0 V m -1 for general public exposure. The average fields equal 5.2 V m -1 for workers, and 0.7 V m -1 for general public. (authors)

In situ occupational and general public exposure to VHF/UHF transmission for air traffic communication.

Science.gov (United States)

Joseph, Wout; Goeminne, Francis; Verloock, Leen; Vermeeren, Günter; Martens, Luc

2012-09-01

Occupational and general public exposure due to very high frequency (VHF)/ultra high frequency (UHF) transmission centres for verbal communication for air traffic control is investigated in situ for the first time. These systems are used for communication with aircraft, resulting in different human exposure from that of classical broadcasting. Measurement methods are proposed for the exposure assessment, and a measurement campaign is executed in three transmission centres. By investigating the temporal behaviour of the VHF signals for 6 d, a realistic worst-case duty cycle of 29 % is determined. Periods of high exposures corresponding with high aircraft traffic are from 7 a.m. to 1 p.m. and in the evening. All measured electric-field values satisfy the International Commission on Non-ionizing Radiation Protection guidelines. Fields vary from 0.2 to 21.1 V m(-1) for occupational exposure and from 0.007 to 8.0 V m(-1) for general public exposure. The average fields equal 5.2 V m(-1) for workers, and 0.7 V m(-1) for general public.

Assessment of Fuel Analysis Methodology and Fission Product Release for 37-Element Fuel by Using the Latest IST Codes during Stagnation Feeder Break in CANDU

International Nuclear Information System (INIS)

Park, Joo Hwan; Jung, Jong Yeob

2009-09-01

Feeder break accident is regarded as one of the design basis accident in CANDU reactor which results in a fuel failure. For a particular range of inlet feeder break sizes, the flow in the channel is reduced sufficiently that the fuel and fuel channel integrity can be significantly affected to have damage in the affected channel, while the remainder of the core remains adequately cooled. The flow in the downstream channel can be more or less stagnated due to a balance between pressure at the break on the upstream side and the reverse driving pressure between the break and the downstream end. In the extreme, this can lead to rapid fuel heatup and fuel damage and failure of the fuel channel similar to that associated with a severe channel flow blockage. Such an inlet feeder break scenario is called a stagnation break. In this report, the fuel analysis methodology and the assessment results of fission product inventory and release during the stagnation feeder break are described for conservatively assumed limiting channel. The accident was assumed to be occurred in the refurbished Wolsong unit 1 and the latest safety codes were used in the analysis. Fission product inventories during the steady state were calculated by using ELESTRES-IST 1.2 code. The whole analysis process was carried out by a script file which was programmed by Perl language. The perl script file was programmed to make all ELESTRES input files for each bundle and each ring based on the given power-burnup history and thermal-hydraulic conditions of the limiting channel and to perform the fuel analysis automatically. The fission product release during the transient period of stagnation feeder break was evaluated by applying Gehl model. The amounts of each isotope's release are conservatively evaluated for additional 2 seconds after channel failure. The calculated fission product releases are provided to the following dose assessment as a source term

The effect of a hay grid feeder on feed consumption and measurement of the gastric pH using an intragastric electrode device in horses: a preliminary report.

Science.gov (United States)

Aristizabal, F; Nieto, J; Yamout, S; Snyder, J

2014-07-01

Obesity and gastric ulceration are highly prevalent in horses. Management modifications for preventing squamous gastric ulceration include frequent feeding and free access to pasture; however, these practices may predispose horses to obesity. To compare the percentage of hay consumed, intragastric pH and horse activity between feeding from the ground and a hay grid feeder. Crossover experimental study. A pH electrode was inserted into the stomach to record the intragastric pH for 48 h. Horses received 1% of their body weight in grass hay twice a day. Horses were assigned to be fed from the ground or a commercial hay grid feeder for 24 h and then switched to the opposite protocol for an additional 24 h. Horses were continuously video-recorded and the percentage of time spent eating or drinking, walking or standing, and lying down were calculated. Two point data were compared by paired t test and pH over time was compared by repeated measures ANOVA. Horses consumed significantly greater amounts of grass hay when fed on the ground compared with a hay grid feeder (n = 9; PpH values (n = 6; P = 0.97), mean intragastric pH over time (n = 6; P = 0.45) the length of time the pH was below 4.0 (n = 6; P = 0.54), and the percentage of time horses spent eating or drinking (n = 9; P = 0.52), walking or standing (n = 9; P = 0.3), or lying down (n = 9; P = 0.4). Within each group horses spent more time eating during the day compared with the night (n = 9; hay grid feeder P = 0.003; ground feeding P = 0.007). The hay grid feeder studied may be used to reduce the amount of hay ingested by horses without reducing the time horses spend eating. © 2013 EVJ Ltd.

Near Field UHF RFID Antenna System Enabling the Tracking of Small Laboratory Animals

Directory of Open Access Journals (Sweden)

Luca Catarinucci

2013-01-01

Full Text Available Radio frequency identification (RFID technology is more and more adopted in a wide range of applicative scenarios. In many cases, such as the tracking of small-size living animals for behaviour analysis purposes, the straightforward use of commercial solutions does not ensure adequate performance. Consequently, both RFID hardware and the control software should be tailored for the particular application. In this work, a novel RFID-based approach enabling an effective localization and tracking of small-sized laboratory animals is proposed. It is mainly based on a UHF Near Field RFID multiantenna system, to be placed under the animals’ cage, and able to rigorously identify the NF RFID tags implanted in laboratory animals (e.g., mice. Once the requirements of the reader antenna have been individuated, the antenna system has been designed and realized. Moreover, an algorithm based on the measured Received Signal Strength Indication (RSSI aiming at removing potential ambiguities in data captured by the multiantenna system has been developed and integrated. The animal tracking system has been largely tested on phantom mice in order to verify its ability to precisely localize each subject and to reconstruct its path. The achieved and discussed results demonstrate the effectiveness of the proposed tracking system.

CPW-fed Circularly Polarized Slot Antenna with Small Gap and Stick-shaped Shorted Strip for UHF FRID Readers

Science.gov (United States)

Pan, Chien-Yuan; Su, Chum-Chieh; Yang, Wei-Lin

2018-04-01

A new circularly polarized (CP) slot antenna with a small gap and a stick-shaped shorted strip is presented. The proposed antenna has a sufficient bandwidth for ultrahigh frequency (UHF) radio-frequency identification (RFID) reader applications. The antenna structure consists of a rectangular slot with a small gap, a stick-shaped shorted strip and a 50 Ω coplanar waveguide (CPW) feedline with an asymmetrical ground plane. By using the stick -shaped shorted strip to disturb magnetic current distribution on the slot, the CP radiation can be generated. The measured results demonstrate that the proposed antenna can reach a 10 dB return loss impedance bandwidth of 14.1 % (894-1030 MHz) and a 3 dB axial ratio (AR) bandwidth of 6.4 % (910-970 MHz). The whole antenna size is 80 × 80 × 1.6 mm3.

The use of multiple imputation for the accurate measurements of individual feed intake by electronic feeders.

Science.gov (United States)

Jiao, S; Tiezzi, F; Huang, Y; Gray, K A; Maltecca, C

2016-02-01

Obtaining accurate individual feed intake records is the key first step in achieving genetic progress toward more efficient nutrient utilization in pigs. Feed intake records collected by electronic feeding systems contain errors (erroneous and abnormal values exceeding certain cutoff criteria), which are due to feeder malfunction or animal-feeder interaction. In this study, we examined the use of a novel data-editing strategy involving multiple imputation to minimize the impact of errors and missing values on the quality of feed intake data collected by an electronic feeding system. Accuracy of feed intake data adjustment obtained from the conventional linear mixed model (LMM) approach was compared with 2 alternative implementations of multiple imputation by chained equation, denoted as MI (multiple imputation) and MICE (multiple imputation by chained equation). The 3 methods were compared under 3 scenarios, where 5, 10, and 20% feed intake error rates were simulated. Each of the scenarios was replicated 5 times. Accuracy of the alternative error adjustment was measured as the correlation between the true daily feed intake (DFI; daily feed intake in the testing period) or true ADFI (the mean DFI across testing period) and the adjusted DFI or adjusted ADFI. In the editing process, error cutoff criteria are used to define if a feed intake visit contains errors. To investigate the possibility that the error cutoff criteria may affect any of the 3 methods, the simulation was repeated with 2 alternative error cutoff values. Multiple imputation methods outperformed the LMM approach in all scenarios with mean accuracies of 96.7, 93.5, and 90.2% obtained with MI and 96.8, 94.4, and 90.1% obtained with MICE compared with 91.0, 82.6, and 68.7% using LMM for DFI. Similar results were obtained for ADFI. Furthermore, multiple imputation methods consistently performed better than LMM regardless of the cutoff criteria applied to define errors. In conclusion, multiple imputation

Altered gut microbiome in a mouse model of Gulf War Illness causes neuroinflammation and intestinal injury via leaky gut and TLR4 activation.

Directory of Open Access Journals (Sweden)

Firas Alhasson

Full Text Available Many of the symptoms of Gulf War Illness (GWI that include neurological abnormalities, neuroinflammation, chronic fatigue and gastrointestinal disturbances have been traced to Gulf War chemical exposure. Though the association and subsequent evidences are strong, the mechanisms that connect exposure to intestinal and neurological abnormalities remain unclear. Using an established rodent model of Gulf War Illness, we show that chemical exposure caused significant dysbiosis in the gut that included increased abundance of phylum Firmicutes and Tenericutes, and decreased abundance of Bacteroidetes. Several gram negative bacterial genera were enriched in the GWI-model that included Allobaculum sp. Altered microbiome caused significant decrease in tight junction protein Occludin with a concomitant increase in Claudin-2, a signature of a leaky gut. Resultant leaching of gut caused portal endotoxemia that led to upregulation of toll like receptor 4 (TLR4 activation in the small intestine and the brain. TLR4 knock out mice and mice that had gut decontamination showed significant decrease in tyrosine nitration and inflammatory mediators IL1β and MCP-1 in both the small intestine and frontal cortex. These events signified that gut dysbiosis with simultaneous leaky gut and systemic endotoxemia-induced TLR4 activation contributes to GW chemical-induced neuroinflammation and gastrointestinal disturbances.

Increased Sensitivity to Binge Alcohol-Induced Gut Leakiness and Inflammatory Liver Disease in HIV Transgenic Rats.

Directory of Open Access Journals (Sweden)

Atrayee Banerjee

Full Text Available The mechanisms of alcohol-mediated advanced liver injury in HIV-infected individuals are poorly understood. Thus, this study was aimed to investigate the effect of binge alcohol on the inflammatory liver disease in HIV transgenic rats as a model for simulating human conditions. Female wild-type (WT or HIV transgenic rats were treated with three consecutive doses of binge ethanol (EtOH (3.5 g/kg/dose oral gavages at 12-h intervals or dextrose (Control. Blood and liver tissues were collected at 1 or 6-h following the last dose of ethanol or dextrose for the measurements of serum endotoxin and liver pathology, respectively. Compared to the WT, the HIV rats showed increased sensitivity to alcohol-mediated gut leakiness, hepatic steatosis and inflammation, as evidenced with the significantly elevated levels of serum endotoxin, hepatic triglycerides, histological fat accumulation and F4/80 staining. Real-time PCR analysis revealed that hepatic levels of toll-like receptor-4 (TLR4, leptin and the downstream target monocyte chemoattractant protein-1 (MCP-1 were significantly up-regulated in the HIV-EtOH rats, compared to all other groups. Subsequent experiments with primary cultured cells showed that both hepatocytes and hepatic Kupffer cells were the sources of the elevated MCP-1 in HIV-EtOH rats. Further, TLR4 and MCP-1 were found to be upregulated by leptin. Collectively, these results show that HIV rats, similar to HIV-infected people being treated with the highly active anti-retroviral therapy (HAART, are more susceptible to binge alcohol-induced gut leakiness and inflammatory liver disease than the corresponding WT, possibly due to additive or synergistic interaction between binge alcohol exposure and HIV infection. Based on these results, HIV transgenic rats can be used as a surrogate model to study the molecular mechanisms of many disease states caused by heavy alcohol intake in HIV-infected people on HAART.

Vertical velocity and turbulence aspects during Mistral events as observed by UHF wind profilers

Directory of Open Access Journals (Sweden)

J.-L. Caccia

2004-11-01

Full Text Available The general purpose of this paper is to experimentally study mesoscale dynamical aspects of the Mistral in the coastal area located at the exit of the Rhône-valley. The Mistral is a northerly low-level flow blowing in southern France along the Rhône-valley axis, located between the French Alps and the Massif Central, towards the Mediterranean Sea. The experimental data are obtained by UHF wind profilers deployed during two major field campaigns, MAP (Mesoscale Alpine Program in autumn 1999, and ESCOMPTE (Expérience sur Site pour COntraindre les Modèles de Pollution atmosphériques et de Transports d'Emission in summer 2001.

Thanks to the use of the time evolution of the vertical profile of the horizontal wind vector, recent works have shown that the dynamics of the Mistral is highly dependent on the season because of the occurrence of specific synoptic patterns. In addition, during summer, thermal forcing leads to a combination of sea breeze with Mistral and weaker Mistral due to the enhanced friction while, during autumn, absence of convective turbulence leads to substantial acceleration as low-level jets are generated in the stably stratified planetary boundary layer. At the exit of the Rhône valley, the gap flow dynamics dominates, whereas at the lee of the Alps, the dynamics is driven by the relative contribution of "flow around" and "flow over" mechanisms, upstream of the Alps. This paper analyses vertical velocity and turbulence, i.e. turbulent dissipation rate, with data obtained by the same UHF wind profilers during the same Mistral events.

In autumn, the motions are found to be globally and significantly subsident, which is coherent for a dry, cold and stable flow approaching the sea, and the turbulence is found to be of pure dynamical origin (wind shears and mountain/lee wave breaking, which is coherent with non-convective situations.

A dual-mode secure UHF RFID tag with a crypto engine in 0.13-μm CMOS

Science.gov (United States)

Tao, Yang; Linghao, Zhu; Xi, Tan; Junyu, Wang; Lirong, Zheng; Hao, Min

2016-07-01

An ultra-high-frequency (UHF) radio frequency identification (RFID) secure tag chip with a non-crypto mode and a crypto mode is presented. During the supply chain management, the tag works in the non-crypto mode in which the on-chip crypto engine is not enabled and the tag chip has a sensitivity of -12.8 dBm for long range communication. At the point of sales (POS), the tag will be switched to the crypto mode in order to protect the privacy of customers. In the crypto mode, an advanced encryption standard (AES) crypto engine is enabled and the sensitivity of the tag chip is switched to +2 dBm for short range communication, which is a method of physical protection. The tag chip is implemented and verified in a standard 0.13-μm CMOS process. Project supported by the National Science & Technology Pillar Program of China (No. 2015BAK36B01).

Real-Time Leaky Lamb Wave Spectrum Measurement and Its Application to NDE of Composites

Science.gov (United States)

Lih, Shyh-Shiuh; Bar-Cohen, Yoseph

1999-01-01

Numerous analytical and theoretical studies of the behavior of leaky Lamb waves (LLW) in composite materials were documented in the literature. One of the key issues that are constraining the application of this method as a practical tool is the amount of data that needs to be acquired and the slow process that is involved with such experiments. Recently, a methodology that allows quasi real-time acquisition of LLW dispersion data was developed. At each angle of incidence the reflection spectrum is available in real time from the experimental setup and it can be used for rapid detection of the defects. This technique can be used to rapidly acquire the various plate wave modes along various angles of incidence for the characterization of the material elastic properties. The experimental method and data acquisition technique will be described in this paper. Experimental data was used to examine a series of flaws including porosity and delaminations and demonstrated the efficiency of the developed technique.

Cooperative spontaneous emission of nano-emitters with inter-emitter coupling in a leaky microcavity

International Nuclear Information System (INIS)

Hong, Suc-Kyoung; Nam, Seog Woo; Yang, Hyung Jin

2015-01-01

We study the spontaneous emission from a few two-level nano-emitters placed in a leaky microcavity with Lorentzian spectral density near a critically damped regime. Collective features of the spontaneous emission are investigated by numerical analysis of the excitation dynamics when initially one nano-emitter is totally excited but we do not know which one. The results show that there are three decay rates in the excitation dynamics, two for simple exponential decays and one for damped oscillatory decay. The excitation dynamics is found to critically depend on the regime of the system. It is shown that the spontaneous emission is enhanced or suppressed depending on whether the system is in the underdamped or overdamped regime, respectively. On the other hand, the cooperative spontaneous emission is suppressed in the underdamped while it is enhanced in the overdamped regime. Furthermore, the effect of the direct inter-emitter coupling on the breaking of the cooperativeness of the spontaneous emission is shown as well. (paper)

General well function for pumping from a confined, leaky, or unconfined aquifer

Science.gov (United States)

Perina, Tomas; Lee, Tien-Chang

2006-02-01

A general well function for groundwater flow toward an extraction well with non-uniform radial flux along the screen and finite-thickness skin, partially penetrating an unconfined, leaky-boundary flux, or confined aquifer is derived via the Laplace and generalized finite Fourier transforms. The mixed boundary condition at the well face is solved as the discretized Fredholm integral equation. The general well function reduces to a uniform radial flux solution as a special case. In the Laplace domain, the relation between the drawdown in the extraction well and flowrate is linear and the formulations for specified flowrate or specified drawdown pumping are interchangeable. The deviation in drawdown of the uniform from non-uniform radial flux solutions depends on the relative positions of the extraction and observation well screens, aquifer properties, and time of observation. In an unconfined aquifer the maximum deviation occurs during the period of delayed drawdown when the effect of vertical flow is most apparent. The skin and wellbore storage in an observation well are included as model parameters. A separate solution is developed for a fully penetrating well with the radial flux being a continuous function of depth.

Field evaluation of cutter and feeder mechanism of chickpea harvester for lentil harvesting

Directory of Open Access Journals (Sweden)

S Kamgar

2016-09-01

Full Text Available Introduction The main producers of lentil are Canada, India, Nepal and China, respectively and Iran is the ninth producer in the world. The hand pulling is the usual method of lentil harvesting. Use of conventional combine because of short leg varieties, wide combine head in dry land and grain losses by cutter bar vibrations is impossible. So a mechanism should be designed to harvest the lentil plants with minimum damage. This mechanism should be evaluated under different tests of crop and machines such as forward speed (FS, grain moisture content (GMC, different varieties and other parameters. Some researchers studied the effects of GMC (Andrews and et al., 1993; Huitink, 2005; Adisa, 2009; Abdi and Jalali, 2013 and FS on grain losses (Geng et al., 1984; Swapan et al., 2001; Mostafavand and Kamgar, 2014; Hunt, 1995. Field tests were conducted at three levels of FS 1.5, 3 and 4.5 km.h-1; three levels of cutting height (CH 4, 8 and 13 cm and two levels of GMC, 8 and 14% on two varieties of lentils including Flip and Shiraz with three replications. Materials and Methods The feeder and cutter mechanism for chickpea harvesting that was the base design of device which is notched wheel and counter shear, was used. The other components of device were dividers, slat and chain feeders, belt and pulleys, chassis, elevator conveyor and storage. Two split plot design based on a randomized complete design was used to determine the effects of above treatments on lentil losses. Results and Discussion The ANOVA results indicated that the all studied factors; FS of feeder and cutter mechanism, CH and GMC had significant effect on losses of Shiraz variety (P0.05. The ranges of losses of Flip variety at 8% GMC were 8.6 to 10% for FS of 1.5 km.h-1, 9.1 to 10.4% for FS of 3 km.h-1and 10.4 to 11.4% for FS of 4.5 km h-1. These ranges at 14% GMC were 7.9 to 8.9% for FS of 1.5 km.h-1, 8.4 to 9.2% for FS of 3 km.h-1and 8.5 to 10% for FS of 4.5 km h-1. The ranges of

Application of a numerical model in the interpretation of a leaky aquifer test

International Nuclear Information System (INIS)

Schroth, B.; Narasimhan, T.N.

1997-01-01

The potential use of numerical models in aquifer analysis is by no means a new concept; yet relatively few engineers and scientists are taking advantage of this powerful tool that is more convenient to use now than ever before. In this technical note the authors present an example of using a numerical model in an integrated analysis of data from a three-layer leaky aquifer system involving well-bore storage, skin effects, variable discharge, and observation wells in the pumped aquifer and in an unpumped aquifer. The modeling detail may differ for other cases. The intent is to show that interpretation can be achieved with reduced bias by reducing assumptions in regard to system geometry, flow rate, and other details. A multiwell aquifer test was carried out at a site on the western part of the Lawrence Livermore National Laboratory (LLNL), located about 60 kilometers east of San Francisco. The test was conducted to hydraulically characterize one part of the site and thus help develop remediation strategies to alleviate the ground-water contamination

Manufacture and testing of the CTB&SBB thermal shield for the ITER magnet feeder system

Energy Technology Data Exchange (ETDEWEB)

Lu, Kun; Liu, Chen; Song, Yuntao; Feng, Hansheng; Ding, Kaizhong, E-mail: kzding@ipp.ac.cn; Wang, Tanbin; Ji, Hui

2015-10-15

The system of International Thermonuclear Experimental Reactor (ITER) feeders is responsible for the power, helium cooling, and instrumentation of the magnets of the coil terminal box and S-bend box (CTB&SBB) thermal shield outside the cryostat. An 80-K rectangular Al thermal shield is hung inside the CTB&SBB to reduce the thermal radiation heat loads of 4.5-K helium. The American Society of Interventional Pain Physicians (ASIPP) will supply all the 31 sets of feeders for ITER. A manufactured prototype of CTB&SBB thermal shield is first quality-tested before the commencement of the series production. First, a detailed configuration of the rectangular Al thermal shield is presented in this article. The paper also presents more information on the manufacturing process of the thermal shield, especially the welding process, the procedure for ensuring good weld quality, and the use of a specially designed tool to ensure <5-mm deformation on such a 7.3-m-long thermal shield during welding. In addition, the cold test and results, including the cooling process with 13-bar and 17.5-g/s 80-K He gas, and the temperature distribution on different panels of the thermal shield are presented. The whole process of manufacture and testing lays a good foundation for the series production of the thermal shield.

Supervisory control and data acquisition system development for superconducting current feeder system of SST-1

International Nuclear Information System (INIS)

Patel, R.; Mahesuria, G.; Gupta, N.C.; Sonara, D.; Panchal, R.; Panchal, P.; Tanna, V.L.; Pradhan, S.

2014-01-01

The Current Feeders System (CFS) is essentially an optimized bridge between the power supply at room temperature and Super Conducting Magnet System (SCMS) of the SST-1 machine at 4.5 K.CFS is a complex electrical and cryogenic network which consists of ten pairs of 10 KA rating helium Vapor cooled Conventional Current Leads (VCCLs), superconducting (SC) current feeder and associated components. For the safe and reliable operation of CFS, it is equipped with different physical process parameters measuring instruments like flow, pressure, temperature, level, vacuum, voltage taps and final control element like control valves, heaters, vacuum pumps etc. PLC program is developed in ladder language for acquiring and controlling the process parameters. Independent SCADA applications developed in WonderwareIntouch software for data communication from PLC, front-end Graphical User Interface (GUI), auto-manual interface, real time trends, history trends, events and alarm pages. Time synchronized communication established between CFS control system and Industrial SQL server (InSQL) Historian for centralized storage of CFS process parameters which intern provides the CFS process data to SST-1 central control room. SCADA based data acquisition and data retrieval system is found to be satisfactory during the recent SST-1 cool down experiment. This paper describes the SCADA and PLC application development and their communication to InSQL server. (author)

Modeling and Control of Low Voltage Flexible Units for Enhanced Operation of Distribution Feeders

DEFF Research Database (Denmark)

Raboni, Pietro; Hu, Weihao; Chaudhary, Sanjay

2013-01-01

In some networks Distributed Generators (DGs) are phasing out conventional power plants in terms of power production but still large efforts are required for providing ancillary services. In this paper the usage of fast response units like a Micro Turbines (MT) and a stationary Electric Vehicle...... Battery (EVB) is proposed for providing primary regulation in grid connected mode and for hierarchically manage an islanded LV distribution feeder. The unit models are described and a novel EVB model directly based on manufacturer’s data is proposed and evaluated comparing its performances with Sim...

A model for strategic selection of feeder management systems: A case study

Energy Technology Data Exchange (ETDEWEB)

Chen, Hsing Hung [Faculty of Management and Administration, Macau University of Science and Technology, Avenue Wei Long, Taipa, Macau (China); Lee, Amy H.I. [Department of Industrial Management, Chung Hua University, No. 707, Sec. 2, Wu Fu Rd., Hsinchu 300 (China); Kang, He-Yau [Department of Industrial Engineering and Management, National Chin-Yi University of Technology, 35, Lane 215, Sec. 1, Chung San Rd., Taiping, Taichung 411 (China)

2010-06-15

The move to integrating distribution management system (DMS) and feeder management system (FMS) in China is becoming the main trend in recent years, in addition to upgrading and rebuilding existing energy management system (EMS) and DMS. However, with increasing complexity in the social environments along with rapidly changing technologies, how to select a suitable contractor and a FMS project is becoming an important issue for electric power companies. This paper first briefly introduces FMS and then lists its critical success criteria. A model that applies a multi-criteria decision-making (MCDM) method, an analytic network process (ANP) associated with benefits, opportunities, costs and risks (BOCR), is constructed to help power companies to select the most suitable FMS project. (author)

Preliminary analysis of accident in SST-1 current feeder system

International Nuclear Information System (INIS)

Roy, Swati; Kanabar, Deven; Garg, Atul; Singh, Amit; Tanna, Vipul; Prasad, Upendra; Srinivasan, R.

2017-01-01

Steady-state Tokamak-1 (SST-1) has 16 superconducting Toroidal field (TF) and 9 superconducting poloidal field (PF) coils rated for 10kA DC. All the TF are connected in series and are operated in DC condition whereas PF coils are individually operated in pulse mode during SST-1 campaigns. SST-1 current feeder system (CFS) houses 9 pairs of PF current leads and 1 pair of TF current leads. During past SST-1 campaign, there were arcing incidents within SST-1 CFS chamber which caused significant damage to PF superconducting current leads as well as its Helium cooling lines of the current leads. This paper brings out the preliminary analysis of the mentioned arcing incident, possible reasons and its investigation thereby laying out the sequence of events. From this analysis and observations, various measures to avoid such arcing incidents have also been proposed. (author)

Differentiation of monkey embryonic stem cells to hepatocytes by feeder-free dispersion culture and expression analyses of cytochrome p450 enzymes responsible for drug metabolism.

Science.gov (United States)

Maruyama, Junya; Matsunaga, Tamihide; Yamaori, Satoshi; Sakamoto, Sakae; Kamada, Noboru; Nakamura, Katsunori; Kikuchi, Shinji; Ohmori, Shigeru

2013-01-01

We reported previously that monkey embryonic stem cells (ESCs) were differentiated into hepatocytes by formation of embryoid bodies (EBs). However, this EB formation method is not always efficient for assays using a large number of samples simultaneously. A dispersion culture system, one of the differentiation methods without EB formation, is able to more efficiently provide a large number of feeder-free undifferentiated cells. A previous study demonstrated the effectiveness of the Rho-associated kinase inhibitor Y-27632 for feeder-free dispersion culture and induction of differentiation of monkey ESCs into neural cells. In the present study, the induction of differentiation of cynomolgus monkey ESCs (cmESCs) into hepatocytes was performed by the dispersion culture method, and the expression and drug inducibility of cytochrome P450 (CYP) enzymes in these hepatocytes were examined. The cmESCs were successfully differentiated into hepatocytes under feeder-free dispersion culture conditions supplemented with Y-27632. The hepatocytes differentiated from cmESCs expressed the mRNAs for three hepatocyte marker genes (α-fetoprotein, albumin, CYP7A1) and several CYP enzymes, as measured by real-time polymerase chain reaction. In particular, the basal expression of cmCYP3A4 (3A8) in these hepatocytes was detected at mRNA and enzyme activity (testosterone 6β-hydroxylation) levels. Furthermore, the expression and activity of cmCYP3A4 (3A8) were significantly upregulated by rifampicin. These results indicated the effectiveness of Y-27632 supplementation for feeder-free dispersed culture and induction of differentiation into hepatocytes, and the expression of functional CYP enzyme(s) in cmESC-derived hepatic cells.

Minimum Lens Size Supporting the Leaky-Wave Nature of Slit Dipole Antenna at Terahertz Frequency

Directory of Open Access Journals (Sweden)

Niamat Hussain

2016-01-01

Full Text Available We designed a slit dipole antenna backed by an extended hemispherical silicon lens and investigated the minimum lens size in which the slit dipole antenna works as a leaky-wave antenna. The slit dipole antenna consists of a planar feeding structure, which is a center-fed and open-ended slot line. A slit dipole antenna backed by an extended hemispherical silicon lens is investigated over a frequency range from 0.2 to 0.4 THz with the center frequency at 0.3 THz. The numerical results show that the antenna gain responses exhibited an increased level of sensitivity to the lens size and increased linearly with increasing lens radius. The lens with the radius of 1.2λo is found to be the best possible minimum lens size for a slit dipole antenna on an extended hemispherical silicon lens.

Research, Development and Demonstration of Peak Load Reduction on Distribution Feeders Using Distributed Energy Resources for the City of Fort Collins

Energy Technology Data Exchange (ETDEWEB)

Sumner, Dennis [City of Fort Collins Utilities, CO (United States); Vosburg, Tom [City of Fort Collins Utilities, CO (United States); Brunner, Steve [Brendle Group, Fort Collins, CO (United States); Gates, Judy [Woodward, Inc., Fort Collins, CO (United States); Howard, Nathan [Spirae, Inc., Fort Collins, CO (United States); Merton, Andrew [Spirae, Inc., Fort Collins, CO (United States); Wright, Don [Spirae, Inc., Fort Collins, CO (United States); Birlingmair, Doug [Spirae, Inc., Fort Collins, CO (United States)

2015-10-01

This project titled “Research, Development and Demonstration of Peak Load Reduction on Distribution Feeders Using Distributed Energy Resources for the City of Fort Collins” evolved in response to the Department of Energy’s (DOE) Funding Opportunity Announcement (FOA) Number DE-PS26-07NT43119. Also referred to as the Fort Collins Renewable and Distributed System Integration (RDSI) Project, the effort was undertaken by a diverse group of local government, higher education and business organizations; and was driven by three overarching goals: I. Fulfill the requirements of the DOE FOA’s Area of Interest 2: Renewable and Distributed System Integration; most notably, to demonstrate the ability to reduce electric system distribution feeder peak load by 15% or more through the coordinated use of Distributed Energy Resources (DER). II. Advance the expertise, technologies and infrastructure necessary to support the long term vision of the Fort Collins Zero Energy District (FortZED) and move towards creating a zero energy district in the Fort Collins “Old Town” area. III. Further the goals of the City of Fort Collins Energy Policy, including the development of a Smart Grid-enabled distribution system in Fort Collins, expanded use of renewable energy, increased energy conservation, and peak load reduction. Through the collaborative efforts of the partner organizations, the Fort Collins RDSI project was successful in achieving all three of these goals. This report is organized into two distinct sections corresponding to the two phases of the project: • Part 1: Feeder Peak Load Reduction and the FortZED Initiative. • Part 2: Forming and Operating Utility Microgrids and Managing Load and Production Variability The original project scope addressed the Part 1 feeder peak load reduction. That work took place from 2009 through 2011 and was largely complete when the project scope was amended to include a demonstration of microgrid operations. While leveraging the

In-situ Mechanical Manipulation of Wellbore Cements as a Solution to Leaky Wells

Science.gov (United States)

Kupresan, D.; Radonjic, M.; Heathman, J.

2013-12-01

mechanical manipulation (shear stress). The main advantage of this methodology is that mechanical manipulation of cement can induce healing of existing fractures, channels and microannulus seal in a wellbore without introducing new materials (e.g. cement squeeze jobs). Furthermore, this methodology is less sensitive to the influence of downhole conditions such as pressure, temperature and formation fluids, since it uses cement pore water as a medium to alter cement sheath. Based on lab experiments observation, it is possible to perceive that once tested at the industrial scale and if successful, the implementation of this method in the field can potentially mitigate leaky wells in CO2 sequestration projects, wellbores completed for hydraulic-fracturing and other conventional oil and gas producing wells. Key words: Wellbore cement integrity; Leaky wells; Cement microstructures; Casing expansion effect on cement mineralogy alterations.

Human amniotic epithelial cell feeder layers maintain mouse embryonic stem cell pluripotency via epigenetic regulation of the c-Myc promoter.

Science.gov (United States)

Liu, Te; Cheng, Weiwei; Liu, Tianjin; Guo, Lihe; Huang, Qin; Jiang, Lizhen; Du, Xiling; Xu, Fuhui; Liu, Zhixue; Lai, Dongmei

2010-02-01

Mouse embryonic stem cells (ESCs) are typically cultured on a feeder layer of mouse embryonic fibroblasts (MEFs), with leukemia inhibitory factor (LIF) added to maintain them in an undifferentiated state. We have previously shown that human amniotic epithelial cells (hAECs) can be used as feeder cells to maintain mouse ESC pluripotency, but the mechanism for this is unknown. In the present study, we found that CpG islands 5' of the c-Myc gene remain hypomethylated in mouse ESCs cultured on hAECs. In addition, levels of acetylation of histone H3 and trimethylation of histone H3K4 in the c-Myc gene promoter were higher in ES cells cultured on hAECs than those in ES cells cultured on MEFs. These data suggested that hAECs can alter mouse ESC gene expression via epigenetic modification of c-Myc, providing a possible mechanism for the hAEC-induced maintenance of ESCs in an undifferentiated state.

Evaluation of the cryogenic mechanical properties of the insulation material for ITER Feeder superconducting joint

Science.gov (United States)

Wu, Zhixiong; Huang, Rongjin; Huang, ChuanJun; Yang, Yanfang; Huang, Xiongyi; Li, Laifeng

2017-12-01

The Glass-fiber reinforced plastic (GFRP) fabricated by the vacuum bag process was selected as the high voltage electrical insulation and mechanical support for the superconducting joints and the current leads for the ITER Feeder system. To evaluate the cryogenic mechanical properties of the GFRP, the mechanical properties such as the short beam strength (SBS), the tensile strength and the fatigue fracture strength after 30,000 cycles, were measured at 77K in this study. The results demonstrated that the GFRP met the design requirements of ITER.

Trophodynamics of inorganic pollutants in a wide-range feeder: The relevance of dietary inputs and biomagnification in the Yellow-legged gull (Larus michahellis)

International Nuclear Information System (INIS)

Ramos, Raül; Ramírez, Francisco; Jover, Lluís

2013-01-01

The suitability of sentinel species to monitor environmental pollution is often hampered by an insufficient knowledge on pollutant trophodynamics. We simultaneously evaluated the influence of individuals' trophic position (as revealed by δ 15 N values) and dietary exploitation of particular systems (using δ 13 C and δ 34 S as proxies) on inorganic pollutant concentrations measured on fledglings' feathers of a wide-range feeder, the Yellow-legged Gull (Larus michahellis), sampled at four locations throughout the Western Mediterranean. Concentrations of total Hg and Se in fledgling feathers (2.43 ± 1.30 and 1.16 ± 0.43 μg/g, respectively) were under the threshold points for deleterious effects on seabirds. On the contrary, alarming Pb concentrations were found in one colony (mean: 1.57 ± 2.46 μg/g, range: 0.16–12.13). With the exception of Pb, pollutant concentrations were positively influenced by consumption of marine resources (as suggested by the positive relationship with δ 34 S values), whereas trophic position played a minor role in determining pollutant body burdens. - Graphical abstract: Individual feeding behaviours in wide-range feeders may represent unavoidable knowledge for an appropriate understanding of contaminant acquisition, adding complexity to the study of the dynamic of contaminants throughout food chains. In this case study, pollutant body burden of Yellow-legged gull (Larus michahellis) chicks was highly influenced by dietary exposure, whereas the influence of trophic position was relatively low. Display Omitted Highlights: ► Diet origin (δ 34 S) and trophic position (δ 15 N) were tested relative to Hg, Se, and Pb levels. ► Hg and Se concentrations in gull feathers were highly influenced by δ 34 S signatures. ► Exploited habitat influenced pollutant levels to a greater extent than trophic position. ► Biomagnification processes contribute less to contamination exposure in wide-range feeders. - Pollutant body burden of a wide

Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae.

Science.gov (United States)

Besseling, E; Foekema, E M; Van Franeker, J A; Leopold, M F; Kühn, S; Bravo Rebolledo, E L; Heße, E; Mielke, L; IJzer, J; Kamminga, P; Koelmans, A A

2015-06-15

Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water volumes. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in intestines of a baleen whale (Megaptera novaeangliae). Contents of its gastrointestinal tract were sieved, dissolved in 10% potassium hydroxide and washed. From the remaining dried material, potential synthetic polymer particles were selected based on density and appearance, and analysed by Fourier transform infrared (FTIR) spectroscopy. Several polymer types (polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, nylon) were found, in varying particle shapes: sheets, fragments and threads with a size of 1mm to 17cm. This diversity in polymer types and particle shapes, can be interpreted as a representation of the varying characteristics of marine plastic and the unselective way of ingestion by M. novaeangliae. Copyright © 2015 Elsevier Ltd. All rights reserved.

On the Feasibility of Gap Detection of Power Transformer Partial Discharge UHF Signals: Gap Propagation Characteristics of Electromagnetic Waves

Directory of Open Access Journals (Sweden)

Xiaoxing Zhang

2017-10-01

Full Text Available This study analyzed the transformer electromagnetic gap propagation characteristics. The influence of gap size is also analyzed, and the results experimentally verified. The obtained results indicated that the gap propagation characteristics of electromagnetic wave signals radiated by the partial discharge (PD source in different directions are substantially different. The intensity of the electromagnetic wave in the gap reaches a maximum at a gap height of 1 cm; and inside the gap, the intensity of the electromagnetic wave depicted an increasing trend at the tail area of the gap. Finally, from the obtained results, some suggestions on where to install sensors in practical systems for ultra high frequency (UHF PD signal detection in the transformer gap are provided. The obtained results confirmed the feasibility of using this approach. These results can be seen as a benchmark and a challenge for further research in this field.

An efficient hybrid evolutionary algorithm based on PSO and HBMO algorithms for multi-objective Distribution Feeder Reconfiguration

Energy Technology Data Exchange (ETDEWEB)

Niknam, Taher [Electronic and Electrical Engineering Department, Shiraz University of Technology, Shiraz (Iran)

2009-08-15

This paper introduces a robust searching hybrid evolutionary algorithm to solve the multi-objective Distribution Feeder Reconfiguration (DFR). The main objective of the DFR is to minimize the real power loss, deviation of the nodes' voltage, the number of switching operations, and balance the loads on the feeders. Because of the fact that the objectives are different and no commensurable, it is difficult to solve the problem by conventional approaches that may optimize a single objective. This paper presents a new approach based on norm3 for the DFR problem. In the proposed method, the objective functions are considered as a vector and the aim is to maximize the distance (norm2) between the objective function vector and the worst objective function vector while the constraints are met. Since the proposed DFR is a multi objective and non-differentiable optimization problem, a new hybrid evolutionary algorithm (EA) based on the combination of the Honey Bee Mating Optimization (HBMO) and the Discrete Particle Swarm Optimization (DPSO), called DPSO-HBMO, is implied to solve it. The results of the proposed reconfiguration method are compared with the solutions obtained by other approaches, the original DPSO and HBMO over different distribution test systems. (author)

Water quality in Pearl Harbor and feeder streams during 1971 - 2001 collected primarily by oceanography students from Leeward Community College (NODC Accession 0000590)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Water quality data were collected in Pearl Harbor and surrounding feeder streams from 30 December 1971 to 24 August 2001. Data were collected by Leeward Community...

State of immune system of patients with infectious-allergic asthma subjected to transcerebral exposure to UHF electron field (27, 12 MHz)

Energy Technology Data Exchange (ETDEWEB)

Bogolyubov, V.M.; Malyavin, A.G.; Pershin, S.B.; Shubina, A.V.; Kubli, S.Kh.; Myshelova, K.P.

An attempt was made to affect immunologic reactions in infectious-allergic asthma patients by subjecting them to transcerebral exposure to UHF electric field. Seventy-six patients, aged 23 to 69 years with varying duration of the disease, were studied. The treatment consisted of 25 exposures lasting from 5 to 15 min; a sham exposure was used on ten patients serving as controls. In all, 55/66 patients experienced clinical improvement lasting 6 to 12 months; only 2/10 control patients had any improvement. After the exposure, the level of T-lymphocytes increased along with blood histamine level; no significant changes were observed in case of B-lymphocytes. This immunologic correction was most effective in patients with atopy, with decreased levels of T-lymphocytes and elevated levels of B-lymphocytes. 12 references.

Automatic feeder for small fish held in tanks

Science.gov (United States)

Joeris, Leonard S.

1965-01-01

The Northville (Michigan) Biological Station has been a center for study of the developmental morphology of coregonid fishes. This work requires the production of numerous individual series of lake herring, lake whitefish, and several species of chubs from parent fish of positively known identity. The offspring of individual pairs or groups of fish must be held in individual tanks from the time they hatch until they reach maturity. One of the important problems in this project has been the poor growth of most fish. Though some have grown well, their growth has been less than that of the same species in nature, and a few fish from each hatch have grown very slowly. Irregularity of feeding may contribute to the slow growth of laboratory fish. The hatchery caretaker feeds them several times during his 8-hour workday, but they must go without food during the remaining 16 hours. The high metabolic rate of small fish, however, appears to make them strongly inclined toward almost continual feeding. Belief that greater, more regular food consumption would result from a mechanical feeder providing a continuous supply of food over a longer period of the day led to development of the equipment described in this paper.

47 CFR 25.223 - Off-axis EIRP spectral density limits for feeder link earth stations in the 17/24 GHz BSS.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Off-axis EIRP spectral density limits for feeder link earth stations in the 17/24 GHz BSS. 25.223 Section 25.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25...

Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas, Mytilus edulis and Cerastoderma edule, in relation to food competition

NARCIS (Netherlands)

Troost, K.; Stamhuis, E.J.; van Duren, L.A; Wolff, W.J.

Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas Mytilus edulis and Cerastoderma edule , in relation to food competition

NARCIS (Netherlands)

Troost, K.; Stamhuis, E.J.; Duren, L.A.; Wolff, W.

2009-01-01

Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

On the preparation of fire-wood splitting machines equipped with feeder devices

International Nuclear Information System (INIS)

Jaeaeskelaeinen, M.

1995-01-01

As part of the Bionergy research programme, the TTS Institute's Department of Forestry conducted a study on firewood splitting machines manufactured by Bilke Oy and Peurala Oy. The said machines are the first of their kind in Finland to be equipped with a feeder device. The Bilke unit is fed by a conveyor belt arrangement while the Peurala unit is equipped with a feeder roll. In addition, both machine types are equipped with a conveyor belt discharging device (e.g. for discharging split wood directly into a trailer). The Bilke unit can also be operated on extraction racks in the woods as the stems due to be split are fed into it from the side and the conveyor discharges the split wood rearwards into the trailer. The trailer can be hooked onto the splitting unit's draw-hook. At the landing, the Bilke unit was used to split a total of 14.2 m 3 and the Peurala unit 8.0 m 3 of approx. 3-metrelong stems averaging 9 cm in diameter. In addition to this, the Bilke unit was used to split ca. 17 m 3 of 3.5 metre-long stems with on average diameter of ca. 6 cm; the stems were in bunches alongside the extraction racks. The person operating the machines for the purposes of this study was a 27-year- old forest worker. The mean productivity achieved at the landing when using the Bilke unit was 7.7 m 3 while that of the Peurala unit was 5.8 m 3 per effective hour. When operated in the woods, the productivity achieved with the Bilke unit (excluding felling-cross cutting-delimbing-bunching and forest haulage work) was 2.8 m 3 /h. When applying a productivity of 1.7 m 3 for felling-cross cutting- delimbing-bunching work and 5.5. m 3 for forest haulage, the entire harvesting chain's productivity was 0.9 m 3 per effective hour

A New Optimization Framework To Solve The Optimal Feeder Reconfiguration And Capacitor Placement Problems

Directory of Open Access Journals (Sweden)

Mohammad-Reza Askari

2015-07-01

Full Text Available Abstract This paper introduces a new stochastic optimization framework based bat algorithm BA to solve the optimal distribution feeder reconfiguration DFR as well as the shunt capacitor placement and sizing in the distribution systems. The objective functions to be investigated are minimization of the active power losses and minimization of the total network costs an. In order to consider the uncertainties of the active and reactive loads in the problem point estimate method PEM with 2m scheme is employed as the stochastic tool. The feasibility and good performance of the proposed method are examined on the IEEE 69-bus test system.

Identification of leaky steam generators by iodine mapping technique and development of tools for cutting of tubes of steam generators of Indian PHWRS

International Nuclear Information System (INIS)

Subba Rao, D.

2006-01-01

Kakrapar Atomic Power Station (2X220 MWe) located in Mandvi Taluka of Surat District in the state of Gujarat is the fifth Nuclear Power Station of the country. It has got an excellent record in the field of operation, safety, public awareness and emergency preparedness. KAPS Unit -1 achieved first criticality in Sep-1992 and was declared for commercial operation in may-1993. KAPS Unit -2 achieved first criticality in Jan-1995 and was declared for commercial operation in Sep-1995. So far station has generated about 30 billion units.Unit-1 achieved 98.4% and was graded as a world's No.1 in year 2002 amongst all CANDU type reactors. KAPS Unit -1 has made another record of operating continuously for more than 300 days in Indian PHWR s operating history. This paper mainly deals with the Indian PHWRs Steam Generators (SG) tube leaks, leaky steam generator identification by Iodine mapping, and development of special tool for cutting, removal and plugging of leaky tubes. These Steam Generators are designed by M/s Kraft Werke Union (KWU) of Siemens Group, West Germany, and Manufactured by M/s ENSA, SPAIN for Unit- 1 and by M/s MAN-GHH, Germany for Unit- 2. First time in October-2002 one of the Steam Generators of Unit-1 developed tube leak. To identify leaky Steam Generator, KAPS has established a method of Iodine mapping. With that the leaky SG was identified in very short time and corrective actions were taken immediately. Total three tube leaks (two in SG-4 of Unit-1 and one in SG-1 of unit-2) were experienced in both Units'. Following observations were made on SG tubes failure: All failures were in cold leg side; All Failures / deterioration locations were in front of main feed water nozzle; All Failures / deterioration locations were observed to be just above tube support plate (TSP) number 4 or 5; Deterioration ( i.e. wall thinning) observed from OD side and these tubes were adjacent to failed tubes; In all the three incidents, failed / deteriorated tubes were

Establishment of rat embryonic stem-like cells from the morula using a combination of feeder layers.

Science.gov (United States)

Sano, Chiaki; Matsumoto, Asako; Sato, Eimei; Fukui, Emiko; Yoshizawa, Midori; Matsumoto, Hiromichi

2009-08-01

Embryonic stem (ES) cells are characterized by pluripotency, in particular the ability to form a germline on injection into blastocysts. Despite numerous attempts, ES cell lines derived from rat embryos have not yet been established. The reason for this is unclear, although certain intrinsic biological differences among species and/or strains have been reported. Herein, using Wistar-Imamichi rats, specific characteristics of preimplantation embryos are described. At the blastocyst stage, Oct4 (also called Pou5f1) was expressed in both the inner cell mass (ICM) and the trophectoderm (TE), whereas expression of Cdx2 was localized to the TE. In contrast, at an earlier stage, expression of Oct4 was detected in all the nuclei in the morula. These stages were examined using a combination of feeder layers (rat embryonic fibroblast [REF] for primary outgrowth and SIM mouse embryo-derived thioguanine- and ouabain-resistant [STO] cells for passaging) to establish rat ES-like cell lines. The rat ES-like cell lines obtained from the morula maintained expression of Oct4 over long-term culture, whereas cell lines derived from blastocysts lost pluripotency during early passage. The morula-derived ES-like cell lines showed Oct4 expression in a long-term culture, even after cryogenic preservation, thawing and EGFP transfection. These results indicate that rat ES-like cell lines with long-term Oct4 expression can be established from the morula of Wistar-Imamichi rats using a combination of feeder layers.

Eddy current array probe for detection of surface breaking cracks in the extrados of feeder bends

International Nuclear Information System (INIS)

Obrutsky, L.S.; Cassidy, R.A.; Chaplin, K.; Martin, P.; Bureau, J.F.

2006-01-01

A new eddy current array probe has been implemented as a straightforward and promising technique for detection of outer diameter (OD) surface-breaking cracks on the extrados of feeder bends. The design is based on previous work performed at AECL, which had demonstrated that eddy current probes with laterally displaced transmit-receive coils can overcome some of the limitations of inspecting ferritic steel components for surface-breaking cracks. The Feeder Integrity Joint Program-CANDU Owners Group Inc. (FIJP-COG) Non-Destructive Evaluation (NDE) Team members commissioned AECL to work in collaboration with the probe manufacturer ZETEC, to develop a field usable eddy current array probe. The objective was to acquire a technique with the following capabilities: fast scanning non-contact inspection technique for surface breaking discontinuities; full inspection of the bend extrados OD surface in a single scan; ability to inspect first and second bends with similar settings and capabilities; permanent record for future reference; axial and circumferential crack detection in a single scan; capability to detect OD surface-breaking cracks, which can provide additional information to that provided by ultrasonic testing (UT) for flaw characterization, and detection threshold: Surface breaking cracks equivalent to a 0.5 mm deep, 10 mm long EDM notch located on the OD of the bend extrados. This paper discusses the basis for probe design, summarizes the experimental work to evaluate probe capabilities and analyzes the results from the field trial. (author)

Eddy current array probe for detection of surface breaking cracks in the extrados of feeder bends

Energy Technology Data Exchange (ETDEWEB)

Obrutsky, L.S.; Cassidy, R.A.; Chaplin, K. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)]. E-mail: obrutskyl@aecl.ca; Martin, P. [NB Power, Point Lepreau NGS, Point Lepreau, New Brunswick (Canada)]. E-mail: PMartin@nbpower.com; Bureau, J.F. [Zetec, Quebec, Quebec (Canada)]. E-mail: jean-francois.bureau@zetec.com

2006-07-01

A new eddy current array probe has been implemented as a straightforward and promising technique for detection of outer diameter (OD) surface-breaking cracks on the extrados of feeder bends. The design is based on previous work performed at AECL, which had demonstrated that eddy current probes with laterally displaced transmit-receive coils can overcome some of the limitations of inspecting ferritic steel components for surface-breaking cracks. The Feeder Integrity Joint Program-CANDU Owners Group Inc. (FIJP-COG) Non-Destructive Evaluation (NDE) Team members commissioned AECL to work in collaboration with the probe manufacturer ZETEC, to develop a field usable eddy current array probe. The objective was to acquire a technique with the following capabilities: fast scanning non-contact inspection technique for surface breaking discontinuities; full inspection of the bend extrados OD surface in a single scan; ability to inspect first and second bends with similar settings and capabilities; permanent record for future reference; axial and circumferential crack detection in a single scan; capability to detect OD surface-breaking cracks, which can provide additional information to that provided by ultrasonic testing (UT) for flaw characterization, and detection threshold: Surface breaking cracks equivalent to a 0.5 mm deep, 10 mm long EDM notch located on the OD of the bend extrados. This paper discusses the basis for probe design, summarizes the experimental work to evaluate probe capabilities and analyzes the results from the field trial. (author)

A Review of Power Distribution Test Feeders in the United States and the Need for Synthetic Representative Networks

Directory of Open Access Journals (Sweden)

Fernando E. Postigo Marcos

2017-11-01

Full Text Available Under the increasing penetration of distributed energy resources and new smart network technologies, distribution utilities face new challenges and opportunities to ensure reliable operations, manage service quality, and reduce operational and investment costs. Simultaneously, the research community is developing algorithms for advanced controls and distribution automation that can help to address some of these challenges. However, there is a shortage of realistic test systems that are publically available for development, testing, and evaluation of such new algorithms. Concerns around revealing critical infrastructure details and customer privacy have severely limited the number of actual networks published and that are available for testing. In recent decades, several distribution test feeders and US-featured representative networks have been published, but the scale, complexity, and control data vary widely. This paper presents a first-of-a-kind structured literature review of published distribution test networks with a special emphasis on classifying their main characteristics and identifying the types of studies for which they have been used. This both aids researchers in choosing suitable test networks for their needs and highlights the opportunities and directions for further test system development. In particular, we highlight the need for building large-scale synthetic networks to overcome the identified drawbacks of current distribution test feeders.

Human amniotic epithelial cell feeder layers maintain human iPS cell pluripotency via inhibited endogenous microRNA-145 and increased Sox2 expression

International Nuclear Information System (INIS)

Liu, Te; Cheng, Weiwei; Huang, Yongyi; Huang, Qin; Jiang, Lizhen; Guo, Lihe

2012-01-01

Currently, human induced pluripotent stem (iPS) cells were generated from patient or disease-specific sources and share the same key properties as embryonic stem cells. This makes them attractive for personalized medicine, drug screens or cellular therapy. Long-term cultivation and maintenance of normal iPS cells in an undifferentiated self-renewing state are a major challenge. Our previous studies have shown that human amniotic epithelial cells (HuAECs) could provide a good source of feeder cells for mouse and human embryonic stem cells, or spermatogonial stem cells, but the mechanism for this is unknown. Here, we examined the effect of endogenous microRNA-145 regulation on Sox2 expression in human iPS cells by HuAECs feeder cells regulation, and in turn on human iPS cells pluripotency. We found that human IPS cells transfected with a microRNA-145 mutant expressed Sox2 at high levels, allowing iPS to maintain a high level of AP activity in long-term culture and form teratomas in SCID mice. Expression of stem cell markers was increased in iPS transfected with the microRNA-145 mutant, compared with iPS was transfected with microRNA-145. Besides, the expression of Drosha proteins of the microRNA-processor complex, required for the generation of precursor pre-miRNA, was significantly increased in human iPS cells cultured on MEF but not on HuAECs. Taken together, these results suggest that endogenous Sox2 expression may be regulated by microRNA-145 in human iPS cells with HuAECs feeder cells, and Sox2 is a crucial component required for maintenance of them in an undifferentiated, proliferative state capable of self-renewal. Highlights: ► microRNA-145 inhibits Sox2 expression in human iPS cells. ► microRNA-145 suppresses the self-renewal and pluripotency of human iPS cells. ► HuAECs regulate expression of microRNA-145 and Sox2 in human iPS cells. ► HuAECs feeder layers maintain human iPS cells pluripotency. ► HuAECs negatively regulates the synthesis of

Human amniotic epithelial cell feeder layers maintain human iPS cell pluripotency via inhibited endogenous microRNA-145 and increased Sox2 expression

Energy Technology Data Exchange (ETDEWEB)

Liu, Te, E-mail: liute79@yahoo.com [School of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Shanghai Geriatric Institute of Chinese Medicine, Shanghai 200031 (China); Cheng, Weiwei [International Peace Maternity and Child Health Hospital, Shanghai Jiaotong University, Shanghai 200030 (China); Huang, Yongyi [Laboratoire PROTEE, Batiment R, Universite du Sud Toulon-Var, 83957 LA GARDE Cedex (France); Huang, Qin; Jiang, Lizhen [Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Guo, Lihe, E-mail: liute79@yahoo.com [Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China)

2012-02-15

Currently, human induced pluripotent stem (iPS) cells were generated from patient or disease-specific sources and share the same key properties as embryonic stem cells. This makes them attractive for personalized medicine, drug screens or cellular therapy. Long-term cultivation and maintenance of normal iPS cells in an undifferentiated self-renewing state are a major challenge. Our previous studies have shown that human amniotic epithelial cells (HuAECs) could provide a good source of feeder cells for mouse and human embryonic stem cells, or spermatogonial stem cells, but the mechanism for this is unknown. Here, we examined the effect of endogenous microRNA-145 regulation on Sox2 expression in human iPS cells by HuAECs feeder cells regulation, and in turn on human iPS cells pluripotency. We found that human IPS cells transfected with a microRNA-145 mutant expressed Sox2 at high levels, allowing iPS to maintain a high level of AP activity in long-term culture and form teratomas in SCID mice. Expression of stem cell markers was increased in iPS transfected with the microRNA-145 mutant, compared with iPS was transfected with microRNA-145. Besides, the expression of Drosha proteins of the microRNA-processor complex, required for the generation of precursor pre-miRNA, was significantly increased in human iPS cells cultured on MEF but not on HuAECs. Taken together, these results suggest that endogenous Sox2 expression may be regulated by microRNA-145 in human iPS cells with HuAECs feeder cells, and Sox2 is a crucial component required for maintenance of them in an undifferentiated, proliferative state capable of self-renewal. Highlights: Black-Right-Pointing-Pointer microRNA-145 inhibits Sox2 expression in human iPS cells. Black-Right-Pointing-Pointer microRNA-145 suppresses the self-renewal and pluripotency of human iPS cells. Black-Right-Pointing-Pointer HuAECs regulate expression of microRNA-145 and Sox2 in human iPS cells. Black-Right-Pointing-Pointer HuAECs feeder

The Leaky Dielectric Model as a Weak Electrolyte Limit of an Electrodiffusion Model

Science.gov (United States)

Mori, Yoichiro; Young, Yuan-Nan

2017-11-01

The Taylor-Melcher (TM) model is the standard model for the electrohydrodynamics of poorly conducting leaky dielectric fluids under an electric field. The TM model treats the fluid as an ohmic conductor, without modeling ion dynamics. On the other hand, electrodiffusion models, which have been successful in describing electokinetic phenomena, incorporates ionic concentration dynamics. Mathematical reconciliation between electrodiffusion and the TM models has been a major issue for electrohydrodynamic theory. Here, we derive the TM model from an electrodiffusion model where we explicitly model the electrochemistry of ion dissociation. We introduce salt dissociation reaction in the bulk and take the limit of weak salt dissociation (corresponding to poor conductors in the TM model.) Assuming small Debye length we derive the TM model with or without the surface charge advection term depending upon the scaling of relevant dimensionless parameters. Our analysis also gives a description of the ionic concentration distribution within the Debye layer, which hints at possible scenarios for electrohydrodynamic singularity formation. In our analysis we also allow for a jump in voltage across the liquid interface which causes a drifting velocity for a liquid drop under an electric field. YM is partially supported by NSF-DMS-1516978 and NSF-DMS-1620316. YNY is partially supported by NSF-DMS-1412789 and NSF-DMS-1614863.

Identification of pectenotoxins in plankton, filter feeders, and isolated cells of a Dinophysis acuminata with an atypical toxin profile, from Chile.

Science.gov (United States)

Blanco, Juan; Alvarez, Gonzalo; Uribe, Eduardo

2007-04-01

A bloom of Dinophysis acuminata produced, in autumn of 2005, a closure of the scallop harvesting in Bahía Inglesa, in the Chilean III region. Isolated cells of this Dinophysis species were shown to contain 180 pg cell(-1) of pectenotoxin 2 but neither okadaic acid nor any of its analogs or derivatives (at least at a detectable level). Examination of plankton and filter-feeder samples covering an area of ca. 350 km, from the location where the toxicity was recorded to Bahía Tongoy, showed that the unique toxin profile found in the first bloom was widespread over that part of Chile and persisted for months. The analysis were carried out by HPLC-ESI-MS using positive ionization mode, with a detection limit below 2 ng of OA mL(-1) of methanolic extract. This is the first report of the presence of pectenotoxins in the plankton of the Pacific coast of America and in the studied filter feeders. This is also the first report of a Dinophysis species containing pectenotoxins and not any toxin of the okadaic acid group.

A numerical study on charging mechanism in leaky dielectric liquids inside the electrostatic atomizers

Science.gov (United States)

Kashir, Babak; Perri, Anthony; Yarin, Alexander L.; Mashayek, Farzad

2017-11-01

The charging of leaky dielectric liquids inside an electrostatic atomizer is studied numerically by developed codes based on OpenFOAM platform. Faradaic reactions are taken into account as the electrification mechanism. The impact of ionic finite size (steric terms) in high voltages is also investigated. The fundamental electrohydrodynamic understanding of the charging mechanism is aimed in the present work where the creation of polarized near-electrode layer and the movement of charges due to hydrodynamic flow are studied in conjunction with the solution of the Navier-Stokes equations. The case of a micro channel electrohydrodynamic flow subjected to two electrodes of the opposite polarity is considered as an example, with the goal to predict the resulting net charge at the exit. Even though the electrodes constitute a small portion of the channel wall, otherwise insulated, it is indicated that the channel length plays a dominant role in the discharging net charge. The ionic fluxes at the electrode surfaces are accounted through the Frumkin-Butler-Volmer relation found from the concurrent in-house experimental investigations. This projects was supported by National science Foundation (NSF) GOALI Grant CBET-1505276.

Effect of feeders in 3D modeling of low impedance multilayer CPW transmission line

Science.gov (United States)

Zaini, R. I.; Kyabaggu, P. B. K.; Sinulingga, E. P.

2018-02-01

Improved characteristics with low dissipation loss MMICs are highly desirable for wireless communications. However, the current industrial MMIC design is mainly based on microstrip concept which suffered from parasitic and unwanted phenomenon especially at higher frequency (>20 GHz). On the other hand, for future wireless technology, higher frequency operation is required and on-wafer microwave characterizations as well as precise modeling of 3D Multilayer CPW components are vital. This project concerns with understanding of the microwave characteristics behavior of Multilayer CPW components in MMIC applications. Feeder effect as unwanted parts in the characteristics has been investigated to determine its relation with the half wavelength resonance of the Multilayer CPW Low Impedance Transmission Line.

Non-leaky vesiculation of large unilamellar vesicles (LUV) induced by plasma high density lipoproteins (HDL): Detection by HPLC

International Nuclear Information System (INIS)

Tischler, U.; Rueckert, D.S.; Schubert, R.; Jaroni, H.W.; Schmidt, K.H.

1989-01-01

Interaction of large unilamellar phosphatidylcholine vesicles (LUV, 75nm) and plasma high density lipoproteins (HDL) resulted in a non-leaky vesiculation of LUV. This vesiculation was detected by a HPLC-system consisting of a combination of three TSK-gel columns (6000PW, 5000PW, 3000SW). With increasing incubation time liposomal [ 14 C]PC, entrapped [ 3 H]inulin, and apoprotein of HDL origin decreased. The decrease was accompanied by a formation of new particles, consisting of liposomal PC and apoprotein. These particles also enclosed [3H]inulin, reflecting a hydrophilic inner space. The formation of the particles reached a maximum after one day of incubation. Retention time was 21 minutes for LUV, 28 minutes for the new particles, and 36 minutes for HDL. In vesicles with membranes consisting of phosphatidylcholine and 30% cholesterol no interactions were observed

Method of detecting stacks with leaky fuel elements in liquid-metal-cooled reactor and apparatus for effecting same

International Nuclear Information System (INIS)

Aristarkhov, N.N.; Efimov, I.A.; Zaistev, B.I.; Peters, I.G.; Tymosh, B.S.

1976-01-01

Described is a method of detecting stacks with leaky fuel elements in a liquid-metal-cooled reactor, consisting in that prior to withdrawing a coolant sample, gas is accumulated in the coolant of the stack being controlled, the reactor being shut down, separated from the sample by means of an inert carrier gas, and the radioactivity of the separated gas is measured. An apparatus for carrying out said method comprises a sampler in the form of a tube parallel to the reactor axis in the hole of a rotating plug and adapted to move along the reactor axis. Made in the top portion of the tube are holes for the introduction of the inert carrier gas and the removal thereof together with the gases evolved from the coolant, while the bottom portion of the tube is provided with a sealing member

Ionospheric modification induced by high-power HF transmitters: a potential for extended range VHF--UHF communications and plasma physics research

International Nuclear Information System (INIS)

Utlaut, W.F.

1975-01-01

When the ionized upper atmosphere of the earth is illuminated by high-power HF radio waves at appropriate frequencies, the temperature of electrons in the ionosphere can be raised substantially. In addition, radio waves with sufficient energy cause parametric instabilities that generate a spectrum of intense plasma waves. Observations of these phenomena have produced new understanding of plasma processes. One consequence of heating and plasma wave generation is that irregularities are formed in the electron distribution which are aligned with the earth's magnetic field. Because of this, a scatterer of large radar cross section is produced, which scatters HF through UHF communication signals over long distance paths, that would not otherwise be normally possible by ionospheric means. Results of radio, radar, communication, and photometric experiments that explored the characteristics of the volume of ionosphere which has been intentionally modified, temporarily, above facilities near Boulder (Platteville), Colo., and at Arecibo, Puerto Rico are summarized

Weaning age of calves fed a high milk allowance by automated feeders: effects on feed, water, and energy intake, behavioral signs of hunger, and weight gains.

Science.gov (United States)

de Passillé, A M; Borderas, T F; Rushen, J

2011-03-01

Dairy calves are increasingly fed large volumes of milk, which reduces feeding motivation and improves weight gain. However, calves often show signs of hunger and lose weight when weaned off milk due to low starter intake. We examined whether delaying the age at weaning would reduce responses to weaning. Calves were raised in groups of 9 and fed milk, starter, hay, and water with automated feeders. In each group, 3 calves were randomly assigned to 1 of 3 treatments: (1) low-milk, early-weaned: fed 6 L/d of milk and weaned at 47 d of age; (2) high-milk early-weaned: fed 12 L/d of milk and weaned at 47 d; (3) high-milk later-weaned: fed 12 L/d of milk and weaned at 89 d of age. Milk, starter, and hay intakes were recorded daily and digestible energy (DE) intake estimated. Feeder visits were recorded. Before weaning, the high-milk calves drank more milk, ate less starter and hay, but had higher DE intakes, gained more weight, and made fewer visits to the milk feeder than the low-milk, early-weaned calves. During and immediately after weaning, the high-fed, early-weaned calves ate less starter and hay, had lower DE intakes, and gained less weight than the low-milk, early-weaned calves and lost their body weight advantage 7 d after weaning. During and immediately after weaning, the high-milk, later-weaned calves ate more starter and hay and had higher DE intakes, higher weight gains, and made fewer visits to the milk feeder than the high-milk, early-weaned calves. They were still heavier than the low-milk, early-weaned calves 18 d after weaning. Delaying the age at which calves are weaned off milk reduces the drop in energy intake and behavioral signs of hunger that result from weaning. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Bacterial Feeders, the Nematode Caenorhabditis elegans and the Flagellate Cercomonas longicauda, have different Effects on Outcome of Competition among the Pseudomonas Biocontrol Strains CHA0 and DSS73

DEFF Research Database (Denmark)

Pedersen, Annette; Nybroe, Ole; Winding, Anne

2009-01-01

How bacterial feeding fauna affects colonization and survival of bacteria in soil is not well understood, which constrains the applicability of bacterial inoculants in agriculture. This study aimed to unravel how food quality of bacteria and bacterial feeders with different feeding habits (the......50090 or one of two biocontrol strains P. fluorescens CHA0 or Pseudomonas sp. DSS73) or combinations of two bacterial strains. DSM50090 is a suitable food bacterium, DSS73 is of intermediate food quality, and CHA0 is inedible to the bacterial feeders. Bacterial and protozoan cell numbers were measured...... predation pressure. Hence, the results suggested that the outcome of competition among bacteria depended on their ability to cope with the prevailing bacterial predator....

UHF-RFID solutions for logistics units management in the food supply chain

Directory of Open Access Journals (Sweden)

Paolo Barge

2013-09-01

Full Text Available The availability of systems for automatic and simultaneous identification of several items belonging to a logistics unit during production, warehousing and delivering can improve supply chain management and speed traceability controls. Radio frequency identification (RFID is a powerful technique that potentially permits to reach this goal, but some aspects as, for instance, food product composition (e.g. moisture content, salt or sugar content and some peculiarities of the production environment (high moisture, high/low temperatures, metallic structures have prevented, so far, its application in food sector. In the food industry, composition and shape of items are much less regular than in other commodities sectors. In addition, a wide variety of packaging, composed by different materials, is employed. As material, size and shape of items to which the tag should be attached strongly influence the minimum power requested for tag functioning, performance improvements can be achieved only selecting suitable RF identifier for the specific combination of food product and packaging. When dealing with logistics units, the dynamic reading of a vast number of tags originates simultaneous broadcasting of signals (tag-to-tag collisions that could affect reading rates and the overall reliability of the identification procedure. This paper reports the results of an extensive analysis of the reading performance of UHF RFID systems for multiple dynamic electronic identification of food packed products in controlled conditions. Products were considered singularly or arranged on a logistics pallet. The effects on reading rate and reading zone of different factors, among which the type of product, the number and position of antennas, the field polarization, the reader RF power output, the interrogation protocol configuration as well as the transit speed, the number of tags and their interactions were analysed and compared.

47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands. 25.258 Section 25.258 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25...

WP EMPLACEMENT CONTROL AND COMMUNICATION EQUIPMENT DESCRIPTIONS

International Nuclear Information System (INIS)

Raczka, N.T.

1997-01-01

The objective and scope of this document are to list and briefly describe the major control and communication equipment necessary for waste package emplacement at the proposed nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the required equipment are explained and summarized in the individual subsections of this document. This task was evaluated in accordance with QAP-2-0 and found not to be quality affecting. Therefore, this document was prepared in accordance with NAP-MG-012. The following control and communication equipment are addressed in this document: (1) Programmable Logic Controllers (PLC's); (2) Leaky Feeder Radio Frequency Communication Equipment; (3) Slotted Microwave guide Communication Equipment; (4) Vision Systems; (5) Radio Control Equipment; and (6) Enclosure Cooling Systems

A simple and efficient feeder-free culture system to up-scale iPSCs on polymeric material surface for use in 3D bioprinting.

Science.gov (United States)

Wong, Chui-Wei; Chen, You-Tzung; Chien, Chung-Liang; Yu, Tien-Yu; Rwei, Syang-Peng; Hsu, Shan-Hui

2018-01-01

The 3D bioprinting and cell/tissue printing techniques open new possibilities for future applications. To facilitate the 3D bioprinting process, a large amount of living cells are required. Induced pluripotent stem cells (iPSCs) represent a promising cell source for bioprinting. However, the maintenance and expansion of undifferentiated iPSCs are expensive and time consuming. Therefore, in this study a culture method to obtain a sufficient amount of healthy and undifferentiated iPSCs in a short-term period was established. The iPSCs could be passaged for twice on tissue culture polystyrene (TCPS) dish with the conditional medium and could adapt to the feeder-free environment. Feeder-free dishes were further prepared from chitosan, chitosan-hyaluronan, silk fibroin, and polyurethane (PU1 and PU2) two-dimensional substrates. The iPSCs cultured on the chitosan substrates showed a higher proliferation rate without losing the stemness feature. Among the different materials, PU2 could be prepared as a thermoresponsive hydrogel, which was a potential ink for 3D bioprinting. The iPSCs cultured on PU2 substrates well survived when further embedded in PU2 hydrogel. Moreover, PU2 hydrogel printed with iPSCs remained structural integrity. The use of PU2 hydrogel to embed iPSCs reduced the injury to iPSCs by shear stress. These results indicate that iPSCs could be expanded on chitosan or PU2 membranes without the feeder layer and then printed in PU2 hydrogel. The combination of these steps could offer a new possibility for future applications of iPSC-based 3D bioprinting in tissue engineering. Copyright © 2017 Elsevier B.V. All rights reserved.

Immunoflourescence and mRNA analysis of human embryonic stem cells (hESCs) grown under feeder-free conditions

DEFF Research Database (Denmark)

Awan, Aashir; Oliveri, Roberto S; Jensen, Pernille L

2010-01-01

onto 16-well glass chambers, and continuing with the general IF and qPCR steps will be provided. The techniques will be illustrated with new results on cellular localization of transcriptional factors and components of the Hedgehog, Wnt, and PDGF signaling pathways to primary cilia in stem cell......This chapter describes the procedures in order to do immunofluorescence (IF) microscopy and quantitative PCR (qPCR) analysis of human embryonic stem cells (hESCs) grown specifically under feeder-free conditions. A detailed protocol outlining the steps from initially growing the cells, passaging...

Implementation of the resonant vibratory feeders control algorithm on Simatic S7-1200 from MATLAB Simulink enviroment

Directory of Open Access Journals (Sweden)

Mitrović Radomir B.

2016-01-01

Full Text Available Simulink is an important tool for modeling and simulation of process and control algorithms. It's expansion, PLC Coder, enables direct conversion of model subsystem into SCL, structured text code, which is then used by PLC IDE to create function blocks. This shortens developing time of algorithms for PLC controller. Also, this reduces possibility for a coding error. This paper describes Simulink PLC Coder and workflow for developing PID control algorithm for Siemens Simatic S7-1200 PLC. Control object used here is resonant vibratory feeder having electromagnetic drive.

Unusual energy properties of leaky backward Lamb waves in a submerged plate.

Science.gov (United States)

Nedospasov, I A; Mozhaev, V G; Kuznetsova, I E

2017-05-01

It is found that leaky backward Lamb waves, i.e. waves with negative energy-flux velocity, propagating in a plate submerged in a liquid possess extraordinary energy properties distinguishing them from any other type of waves in isotropic media. Namely, the total time-averaged energy flux along the waveguide axis is equal to zero for these waves due to opposite directions of the longitudinal energy fluxes in the adjacent media. This property gives rise to the fundamental question of how to define and calculate correctly the energy velocity in such an unusual case. The procedure of calculation based on incomplete integration of the energy flux density over the plate thickness alone is applied. The derivative of the angular frequency with respect to the wave vector, usually referred to as the group velocity, happens to be close to the energy velocity defined by this mean in that part of the frequency range where the backward mode exists in the free plate. The existence region of the backward mode is formally increased for the submerged plate in comparison to the free plate as a result of the liquid-induced hybridization of propagating and nonpropagating (evanescent) Lamb modes. It is shown that the Rayleigh's principle (i.e. equipartition of total time-averaged kinetic and potential energies for time-harmonic acoustic fields) is violated due to the leakage of Lamb waves, in spite of considering nondissipative media. Copyright © 2017 Elsevier B.V. All rights reserved.

Leaky Vaccines Protect Highly Exposed Recipients at a Lower Rate: Implications for Vaccine Efficacy Estimation and Sieve Analysis

Directory of Open Access Journals (Sweden)

Paul T. Edlefsen

2014-01-01

Full Text Available “Leaky” vaccines are those for which vaccine-induced protection reduces infection rates on a per-exposure basis, as opposed to “all-or-none” vaccines, which reduce infection rates to zero for some fraction of subjects, independent of the number of exposures. Leaky vaccines therefore protect subjects with fewer exposures at a higher effective rate than subjects with more exposures. This simple observation has serious implications for analysis methodologies that rely on the assumption that the vaccine effect is homogeneous across subjects. We argue and show through examples that this heterogeneous vaccine effect leads to a violation of the proportional hazards assumption, to incomparability of infected cases across treatment groups, and to nonindependence of the distributions of the competing failure processes in a competing risks setting. We discuss implications for vaccine efficacy estimation, correlates of protection analysis, and mark-specific efficacy analysis (also known as sieve analysis.

The impact of deprivation on youth violence: a comparison of cities and their feeder towns.

Science.gov (United States)

Jones, S J; Sivarajasingam, V; Shepherd, J

2011-06-01

66,000 children and adolescents are treated at emergency departments (EDs) in England and Wales each year for assault injury. The aim of this study was to compare adolescent assault injury rates in cities and towns and determine how assault injury varies with deprivation and gender. The study was set in three cities in Wales, UK, and their surrounding towns. Subjects were 11-17 year olds treated for assault injury at one of seven EDs from 1 October 2005 to 30 September 2006. Area of residence (electoral divisions, EDivs) was identified from patient postcode. EDivs were aggregated into deprivation fifths for males and females and cities and towns. Assault injury rates, rate ratios and 95% CIs were calculated. 1472 children and adolescents of 11-17 years old were treated for assault injury. Male city assault injury rates were 14.2/1000 11-17 year olds; and 13.1 in towns. Female city assault injury rates were 6.0; and 5.6 in towns. In the most deprived city areas males had assault injury rates 2.6 times (95% CI 1.85 to 3.59) that of the most affluent, compared with 2.0 times in towns (95% CI 1.39 to 2.86). For females, the most deprived city areas had assault injury rates 5.3 times that of the most affluent (95% CI 2.93 to 9.41), compared with 2.8 times in towns (95% CI 1.47 to 5.28). Injury in youth violence increased with increasing deprivation in cities and their feeder towns. This was true for boys and girls, though rates for boys were consistently higher. This link between assault injury and deprivation was stronger for girls in cities than in feeder towns. Strategies to prevent youth violence need to include improved safeguarding arrangements for girls living in the most deprived city areas.

Robust and highly-efficient differentiation of functional monocytic cells from human pluripotent stem cells under serum- and feeder cell-free conditions.

Directory of Open Access Journals (Sweden)

Masakatsu D Yanagimachi

Full Text Available Monocytic lineage cells (monocytes, macrophages and dendritic cells play important roles in immune responses and are involved in various pathological conditions. The development of monocytic cells from human embryonic stem cells (ESCs and induced pluripotent stem cells (iPSCs is of particular interest because it provides an unlimited cell source for clinical application and basic research on disease pathology. Although the methods for monocytic cell differentiation from ESCs/iPSCs using embryonic body or feeder co-culture systems have already been established, these methods depend on the use of xenogeneic materials and, therefore, have a relatively poor-reproducibility. Here, we established a robust and highly-efficient method to differentiate functional monocytic cells from ESCs/iPSCs under serum- and feeder cell-free conditions. This method produced 1.3 × 10(6 ± 0.3 × 10(6 floating monocytes from approximately 30 clusters of ESCs/iPSCs 5-6 times per course of differentiation. Such monocytes could be differentiated into functional macrophages and dendritic cells. This method should be useful for regenerative medicine, disease-specific iPSC studies and drug discovery.

Theoretical analysis of leaky surface acoustic waves of point-focused acoustic lens and some experiments

International Nuclear Information System (INIS)

Ishikawa, Isao; Suzuki, Yoshiaki; Ogura, Yukio; Katakura, Kageyoshi

1997-01-01

When a point-focused acoustic lens in the scanning acoustic microscope (SAM) is faced to test specimen and defocused to some extent, two effective echoes can be obtained. One is the echo of longitudinal wave, which is normally incident upon the specimen of an on-axis beam in the central region of the lens and is reflected normal to the lens surface, hence detected by the transducer. The other is of leaky surface acoustic waves(LSAW), which are mode converted front a narrow beam of off-axis longitudinal wave, then propagate across the surface of the specimen and reradiate at angles normal to the lens surface, thus detected by the transducer. These two echoes are either interfered or separated with each other depending ell the defocused distance. It turned out theoretically that the LSAW have a narrow focal spot in the central region of the point-focused acoustic lens, whose size is approximately 40% of the LSAW wavelength. On top of that, a wavelength of LSAW is about 50% short as that of longitudinal wave. So, It is expected that high resolution images can be obtained provided LSAW are used in the scanning acoustic microscope.

Growth factor expression pattern of homologous feeder layer for culturing buffalo embryonic stem cell-like cells.

Science.gov (United States)

Sharma, Ruchi; George, Aman; Kamble, Nitin M; Chauhan, Manmohan S; Singla, Suresh; Manik, Radhey S; Palta, Prabhat

2012-01-01

The present study examined the expression profile of buffalo fetal fibroblasts (BFF) used as a feeder layer for embryonic stem (ES) cell-like cells. The expression of important growth factors was detected in cells at different passages. Mitomycin-C inactivation increased relative expression levels of ACTIVIN-A, TGF-β1, BMP-4 and GREMLIN but not of fibroblast growth factor-2 (FGF-2). The expression level of ACTIVIN-A, transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-4 (BMP-4) and FGF-2 was similar in buffalo fetal fibroblast (BFF) cultured in stem cell medium (SCM), SCM+1000IU mL(-1) leukemia inhibitory factor (LIF), SCM+5 ngmL(-1) FGF-2 or SCM+LIF+FGF-2 for 24 h whereas GREMLIN expression was higher in FGF-2-supplemented groups. In spent medium, the concentration of ACTIVIN-A was higher in FGF-2-supplemented groups whereas that of TGF-β1 was similar in SCM and LIF+FGF-2, which was higher than when either LIF or FGF-2 was used alone. Following culture of ES cell-like cells on a feeder layer for 24 h, the TGF-β1 concentration was higher with LIF+FGF-2 than with LIF or FGF-2 alone which, in turn, was higher than that in SCM. In the LIF+FGF-2 group, the concentration of TGF-β1 was lower and that of ACTIVIN-A was higher in spent medium at 24 h than at 48 h of culture. These results suggest that BFF produce signalling molecules that may help in self-renewal of buffalo ES cell-like cells.

Development of an extruder-feeder biomass direct liquefaction process. Volume 2, Parts 4--8: Final report

Energy Technology Data Exchange (ETDEWEB)

White, D.H.; Wolf, D. [Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering

1991-10-01

As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE`s Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

THE METHOD OF SELECTION OF THE SETPOINT HIGH SPEED FEEDER SWITCH OF 3,3KV DC WITH MICROPROCESSOR-BASED PROTECTION SYSTEMS

Directory of Open Access Journals (Sweden)

P. Ye. Mykhalichenko

2009-10-01

Full Text Available In the article a new procedure of choice of minimum current jump for action of fast-acting switches of 3.3 kV DC traction substations intended for the use in the microprocessor protection system of feeders is described. This procedure is more perfect than existing one on the current increment and uses the results of mathematical simulation of the traction electric supply system.

Challenges associated with the current processes for ultrasonic inspection of CANDU reactor feeder piping

Energy Technology Data Exchange (ETDEWEB)

Machowski, C. [Babcock & Wilcox Canada Ltd., Cambridge, Ontario (Canada)

2012-07-01

CANDU® PHT Feeder Piping is generally constructed from SA106 Grade B carbon steel, which is known to be susceptible to flow accelerated corrosion when exposed to certain environmental conditions. The configuration of the CANDU reactor promotes thinning of the inside surface of the pipe walls, predominantly at the outlet feeders. Inspection of this piping is currently conducted using ultrasonic techniques and is governed by the requirements established by the CANDU Owners Group (COG). There are many challenges associated with these inspections as a result of the complexity of the reactor piping configuration. Geometrical anomalies on the surface of the pipe and non-circular geometries at the tight radius bends hinder the performance of conventional ultrasonic techniques. This can cause lost signals in areas of interest, which in turn often results in rework in order to satisfy the inspection requirements and justify fitness for service of these components. There are also many inspection sites which have limited access due to physical restrictions on the reactor face; therefore in order to maximize the performance of an inspection campaign, it is paramount that the inspection personnel and the inspection technology be well integrated through training simulations prior to execution. These inspection challenges increase the complexity of the analysis process as ultrasonic signals get distorted and lost as a result of non-circular pipe geometries. In order to ensure a high level of integrity in the analysis results, a conservative process is utilized in which two analysts independently examine the data, and a third analyst reviews their results and submits the final call. A Data Management Software application (DMS) is used to input and store the three analysis results. Another important function of the DMS is to provide a communication link between the different work-groups associated with the inspection activities. The focus of this presentation discusses: �

A feeder-free, human plasma-derived hydrogel for maintenance of a human embryonic stem cell phenotype in vitro

Directory of Open Access Journals (Sweden)

Lewis Fiona C

2012-08-01

Full Text Available Abstract Background Human embryonic stem cells (hESCs represent a tremendous resource for cell therapies and the study of human development; however to maintain their undifferentiated state in vitro they routinely require the use of mouse embryonic fibroblast (MEF feeder-layers and exogenous protein media supplementation. Results These well established requirements can be overcome and in this study, it will be demonstrated that phenotypic stability of hESCs can be maintained using a novel, human plasma protein-based hydrogel as an extracellular culture matrix without the use of feeder cell co-culture. hESCs were resuspended in human platelet poor plasma (PPP, which was gelled by the addition of calcium containing DMEM-based hESC culture medium. Phenotypic and genomic expression of the pluripotency markers OCT4, NANOG and SOX2 were measured using immunohistochemistry and qRT-PCR respectively. Typical hESC morphology was demonstrated throughout in vitro culture and both viability and phenotypic stability were maintained throughout extended culture, up to 25 passages. Conclusions PPP-derived hydrogel has demonstrated to be an efficacious alternative to MEF co-culture with its hydrophilicity allowing for this substrate to be delivered via minimally invasive procedures in a liquid phase with polymerization ensuing in situ. Together this provides a novel technique for the study of this unique group of stem cells in either 2D or 3D both in vitro and in vivo.

On AC-Field-Induced Nonlinear Electroosmosis next to the Sharp Corner-Field-Singularity of Leaky Dielectric Blocks and Its Application in on-Chip Micro-Mixing

Directory of Open Access Journals (Sweden)

Yukun Ren

2018-02-01

Full Text Available Induced-charge electroosmosis has attracted lots of attention from the microfluidic community over the past decade. Most previous researches on this subject focused on induced-charge electroosmosis (ICEO vortex streaming actuated on ideally polarizable surfaces immersed in electrolyte solutions. Starting from this point, we conduct herein a linear asymptotic analysis on nonlinear electroosmotic flow next to leaky dielectric blocks of arbitrary electrical conductivity and dielectric permittivity in harmonic AC electric fields, and theoretically demonstrate that observable ICEO fluid motion can be generated at high field frequencies in the vicinity of nearly insulating semiconductors, a very low electrical conductivity, of which can evidently increase the double-layer relaxation frequency (inversely proportional to the solid permittivity to be much higher than the typical reciprocal RC time constant for induced double-layer charging on ideally polarizable surfaces. A computational model is developed to study the feasibility of this high-frequency vortex flow field of ICEO for sample mixing in microfluidics, in which the usage of AC voltage signal at high field frequencies may be beneficial to suppress electrochemical reactions to some extent. The influence of various parameters for developing an efficient mixer is investigated, and an integrated arrangement of semiconductor block array is suggested for achieving a reliable mixing performance at relatively high sample fluxes. Our physical demonstration with high-frequency ICEO next to leaky dielectric blocks using a simple channel structure offers valuable insights into the design of high-throughput micromixers for a variety of lab-on-a-chip applications.

Overview of improvements in work practices and instrumentation for CANDU primary heat transport feeders in-service inspections

Energy Technology Data Exchange (ETDEWEB)

Marcotte, O., E-mail: olivier@nucleom.ca [Nucleom Inc., Quebec, Quebec (Canada); Rousseau, G., E-mail: rousseau.gilles.a@hydro.qc.ca [Hydro Quebec, Becancour, Quebec (Canada); Rochefort, E., E-mail: erochfort@zetec.com [Zetec Canada, Quebec, Quebec (Canada)

2013-01-15

The Canadian nuclear industry has developed many advanced non-destructive inspection techniques to be applied safely in hazardous environments in recent years. Automated systems, manual tooling and specialized software modules have been designed since early 2000s to provide complete and very efficient fitness for service inspection of primary heat transport system carbon steel feeder pipes. These techniques deal with complex geometries, difficult access and, radioactive environment. Complementary NDE techniques, namely Ultrasounds, eddy current, phased-array UT and automated scanners are used. This presentation describes the improvements in inspection practices and the advanced data analysis features. (author)

Using Human Gestures and Generic Skills to Instruct a Mobile Robot Arm in a Feeder Filling Scenario

DEFF Research Database (Denmark)

Pedersen, Mikkel Rath; Høilund, Carsten; Krüger, Volker

2012-01-01

Mobile robots that have the ability to cooperate with humans are able to provide new possibilities to manufac- turing industries. In this paper, we discuss our mobile robot arm that a) can provide assistance at different locations in a factory and b) that can be programmed using complex human...... actions such as pointing in Take this object. In this paper, we discuss the use of the mobile robot for a feeding scenario where a human operator specifies the parts and the feeders through pointing gestures. The system is partially built using generic robotic skills. Through extensive experiments, we...

Derivation and characterization of the NIH registry human stem cell line NYSCF100 line under defined feeder-free conditions

Directory of Open Access Journals (Sweden)

Ana Sevilla

2018-05-01

Full Text Available The human embryonic stem cell line NYSCFe001-A was derived from a day 6 blastocyst in feeder-free and antibiotic free conditions. The blastocyst was voluntarily donated for research as surplus after in vitro fertilization treatment following informed consent. The NYSCFe001-A line, registered as NYSCF100 on the NIH registry, presents normal karyotype, is mycoplasma free, expresses all the pluripotency markers and has the potential to differentiate into all three germ layers in vitro.

Understanding the leaky engineering pipeline: Motivation and job adaptability of female engineers

Science.gov (United States)

Saraswathiamma, Manjusha Thekkedathu

This dissertation is a mixed-method study conducted using qualitative grounded theory and quantitative survey and correlation approaches. This study aims to explore the motivation and adaptability of females in the engineering profession and to develop a theoretical framework for both motivation and adaptability issues. As a result, this study endeavors to design solutions for the low enrollment and attenuation of female engineers in the engineering profession, often referred to as the "leaky female engineering pipeline." Profiles of 123 female engineers were studied for the qualitative approach, and 98 completed survey responses were analyzed for the quantitative approach. The qualitative, grounded-theory approach applied the constant comparison method; open, axial, and selective coding was used to classify the information in categories, sub-categories, and themes for both motivation and adaptability. The emergent themes for decisions motivating female enrollment include cognitive, emotional, and environmental factors. The themes identified for adaptability include the seven job adaptability factors: job satisfaction, risk- taking attitude, career/skill development, family, gender stereotyping, interpersonal skills, and personal benefit, as well as the self-perceived job adaptability factor. Illeris' Three-dimensional Learning Theory was modified as a model for decisions motivating female enrollment. This study suggests a firsthand conceptual parallelism of McClusky's Theory of Margin for the adaptability of female engineers in the profession. Also, this study attempted to design a survey instrument to measure job adaptability of female engineers. The study identifies two factors that are significantly related to job adaptability: interpersonal skills (related.

Minimal incorporation of Deepwater Horizon oil by estuarine filter feeders

International Nuclear Information System (INIS)

Fry, Brian; Anderson, Laurie C.

2014-01-01

Highlights: • Oil from the Deepwater Horizon oil spill entered Louisiana bays in mid-2010. • Oil was used minimally (<1%) in diets of mussels and barnacles. • Also, oil did not enhance planktonic respiration rates. • Use of oil carbon was relatively small in these productive estuarine food webs. - Abstract: Natural abundance carbon isotope analyses are sensitive tracers for fates and use of oil in aquatic environments. Use of oil carbon in estuarine food webs should lead to isotope values approaching those of oil itself, −27‰ for stable carbon isotopes reflecting oil origins and −1000‰ for carbon-14 reflecting oil age. To test for transfer of oil from the 2010 Deepwater Horizon spill into estuarine food webs, filter-feeding barnacles (Balanus sp.) and marsh mussels (Geukensia demissa) were collected from Louisiana estuaries near the site of the oil spill. Carbon-14 analyses of these animals from open waters and oiled marshes showed that oil use was <1% and near detection limits estimated at 0.3% oil incorporation. Respiration studies showed no evidence for enhanced microbial activity in bay waters. Results are consistent with low dietary impacts of oil for filter feeders and little overall impact on respiration in the productive Louisiana estuarine systems

Complete nutrient content of four species of commercially available feeder insects fed enhanced diets during growth.

Science.gov (United States)

Finke, Mark D

2015-11-01

Commercially raised feeder insects used to feed captive insectivores are a good source of many nutrients but are deficient in several key nutrients. Current methods used to supplement insects include dusting and gut-loading. Here, we report on the nutrient composition of four species of commercially raised feeder insects fed a special diet to enhance their nutrient content. Crickets, mealworms, superworms, and waxworms were analyzed for moisture, crude protein, fat, ash, acid detergent fiber, total dietary fiber, minerals, amino acids, fatty acids, vitamins, taurine, carotenoids, inositol, and cholesterol. All four species contained enhanced levels of vitamin E and omega 3 fatty acids when compared to previously published data for these species. Crickets, superworms, and mealworms contained β-carotene although using standard conversion factors only crickets and superworms would likely contain sufficient vitamin A activity for most species of insectivores. Waxworms did not contain any detectable β-carotene but did contain zeaxanthin which they likely converted from dietary β-carotene. All four species contained significant amounts of both inositol and cholesterol. Like previous reports all insects were a poor source of calcium and only superworms contained vitamin D above the limit of detection. When compared to the nutrient requirements as established by the NRC for growing rats or poultry, these species were good sources of most other nutrients although the high fat and low moisture content of both waxworms and superworms means when corrected for energy density these two species were deficient in more nutrients than crickets or mealworms. These data show the value of modifying the diet of commercially available insects as they are growing to enhance their nutrient content. They also suggest that for most insectivores properly supplemented lower fat insects such as crickets, or smaller mealworms should form the bulk of the diet. © 2015 The Authors. Zoo Biology

USULAN PERBAIKAN OPERATION POINT SHEET PADA MESIN FEEDER AIDA 1100 PT. XXX DENGAN MENGGUNAKAN METODE SMED

Directory of Open Access Journals (Sweden)

Ary Arvianto

2012-02-01

Full Text Available Single Minute Exchange of Die (SMED merupakan salah satu alat lean yang penting untuk mengurangi waste dan meningkatkan fleksibilitas dalam proses manufaktur yang memungkinkan dalam pengurangan ukuran lot dan perbaikan aliran manufaktur. SMED mengurangi waktu non-produktif dengan mempersatukan dan standardisasi operasi dalam pergantian alat, dengan menggunakan teknik sederhana dan aplikasi yang mudah. Namun proses tersebut tidak dapat memberikan hasil yang  spesifik dalam pelaksanaannya, dimana masih dapat dilakukan suatu perbaikan. Untuk mengatasi hal ini, data statistik dan alat-alat teknik industri dapat diintegrasikan dalam pendekatan SMED untuk meningkatkan hasil penerapan SMED. Penerapan pendekatan SMED yang diusulkan diuji untuk mesin feeder didalam industri otomotif PT. XXX. Implementasi ini memungkinkan adanya pengurangan waktu setup, melalui reorganisasi sumber daya internal perusahaan tanpa membutuhkan investasi yang signifikan.   Kata kunci: Lean manufacturing systems, Single Minute Exchange of Die, Quick ChangeOver.     Single Minute Exchange of Die (SMED is one of the essential lean tools to reduce waste and increase flexibility in manufacturing processes that enable the reduction of lot size and improving manufacturing flow. SMED reduces non-productive time by streamlining and standardizing operations in the turn of the tool, using simple techniques and easy application. But the process can not provide a specific result in the implementation, which can still be an improvement. To overcome this, statistical data and tools can be integrated in industrial engineering approaches to improve outcomes SMED SMED implementation. The proposed application of SMED approach was tested for the automotive industry in the feeder machine PT. XXX. This implementation allows for the reduction of setup time, through the reorganization of the company's internal resources without requiring significant investment. Keywords: Lean manufacturing

Translation of the shallot virus X TGB3 gene depends on non-AUG initiation and leaky scanning.

Science.gov (United States)

Lezzhov, Alexander A; Gushchin, Vladimir A; Lazareva, Ekaterina A; Vishnichenko, Valery K; Morozov, Sergey Y; Solovyev, Andrey G

2015-10-01

Triple gene block (TGB), a conserved gene module found in the genomes of many filamentous and rod-shaped plant viruses, encodes three proteins, TGB1, TGB2 and TGB3, required for viral cell-to-cell movement through plasmodesmata and systemic transport via the phloem. The genome of Shallot virus X, the type species of the genus Allexivirus, includes TGB1 and TGB2 genes, but contains no canonical ORF for TGB3 protein. However, a TGB3-like protein-encoding sequence lacking an AUG initiator codon has been found in the shallot virus X (ShVX) genome in a position typical for TGB3 genes. This putative TGB3 gene is conserved in all allexiviruses. Here, we carried out sequence analysis to predict possible non-AUG initiator codons in the ShVX TGB3-encoding sequence. We further used an agroinfiltration assay in Nicotiana benthamiana to confirm this prediction. Site-directed mutagenesis was used to demonstrate that the ShVX TGB3 could be translated on a bicistronic mRNA template via a leaky scanning mechanism.

Acoustic streaming in a microfluidic channel with a reflector: Case of a standing wave generated by two counterpropagating leaky surface waves.

Science.gov (United States)

Doinikov, Alexander A; Thibault, Pierre; Marmottant, Philippe

2017-07-01

A theory is developed for the modeling of acoustic streaming in a microfluidic channel confined between an elastic solid wall and a rigid reflector. A situation is studied where the acoustic streaming is produced by two leaky surface waves that propagate towards each other in the solid wall and thus form a combined standing wave in the fluid. Full analytical solutions are found for both the linear acoustic field and the field of the acoustic streaming. A dispersion equation is derived that allows one to calculate the wave speed in the system under study. The obtained solutions are used to consider particular numerical examples and to reveal the structure of the acoustic streaming. It is shown that two systems of vortices are established along the boundaries of the microfluidic channel.

Normal overall leakiness of microvasculature for albumin in patients with chronic obstructive lung disease (COLD).

Science.gov (United States)

Henriksen, J H; Kok-Jensen, A

1984-04-01

The overall extravasation rate of albumin, TER (i.e. the fraction of the intravascular albumin mass (IVM) passing into, and during steady state returning from, the extravascular space per unit time) was determined from the disappearance of i.v. injected radioiodinated serum albumin in seven patients with severe chronic obstructive lung disease (COLD) and in seven normal controls. Arterial oxygen tension in patients with COLD was median 60 mmHg (range 47-80, normal greater than 75 mmHg), vital capacity was on the average 55% of expected normal value (median 1.80 litre, range 1.45-1.95), and forced expired volume in first sec was decreased to 21% of expected normal value (median 0.55 litre, range 0.40-0.70). Right-heart catheterization revealed pulmonary hypertension in all but one patient. TER in patients with COLD was median 6.1% IVM/h (range 3.5-10.1) as compared to that of normal controls 6.0% IVM/h (range 4.3-7.4), indicating that no significant change in microvascular leakiness to albumin could be found in patients with COLD. Thus, the results bring no support to a generally increased microvascular permeability to proteins in patients with COLD.

Advanced feeder-free generation of induced pluripotent stem cells directly from blood cells.

Science.gov (United States)

Trokovic, Ras; Weltner, Jere; Nishimura, Ken; Ohtaka, Manami; Nakanishi, Mahito; Salomaa, Veikko; Jalanko, Anu; Otonkoski, Timo; Kyttälä, Aija

2014-12-01

Generation of validated human induced pluripotent stem cells (iPSCs) for biobanking is essential for exploring the full potential of iPSCs in disease modeling and drug discovery. Peripheral blood mononuclear cells (PBMCs) are attractive targets for reprogramming, because blood is collected by a routine clinical procedure and is a commonly stored material in biobanks. Generation of iPSCs from blood cells has previously been reported using integrative retroviruses, episomal Sendai viruses, and DNA plasmids. However, most of the published protocols require expansion and/or activation of a specific cell population from PBMCs. We have recently collected a PBMC cohort from the Finnish population containing more than 2,000 subjects. Here we report efficient generation of iPSCs directly from PBMCs in feeder-free conditions in approximately 2 weeks. The produced iPSC clones are pluripotent and transgene-free. Together, these properties make this novel method a powerful tool for large-scale reprogramming of PBMCs and for iPSC biobanking. ©AlphaMed Press.

A Survey of Pesticide Accumulation in a Specialist Feeder, the Koala (Phascolarctos cinereus).

Science.gov (United States)

Marschner, Caroline; Higgins, Damien P; Krockenberger, Mark B

2017-09-01

To maintain profitability in Australia's agricultural and urban landscapes pesticides are used throughout the range of koala habitats. The koala is a specialist feeder, reliant on metabolic enzyme capacities to utilise a toxic diet of eucalypt leaves and is potentially prone to adverse effects when xenobiotic interactions between dietary and anthropogenic xenobiotics occur. The aim of this study was to investigate accumulation of frequently used pesticides in wild koalas in 4 areas of New South Wales and Queensland. Liver samples of 57 deceased koalas were collected from care facilities and analysed using a modified QuEChERS extraction method followed by GCMSMS, HRLCMS and LCMSMS. No accumulation of any of the 166 investigated pesticides was found. Data indicate hepatic accumulation of pesticides in this species is uncommon even with close interactions with intensive land use. Despite the lack of hepatic bioaccumulation, this study cannot exclude a direct effect on hepatocellular metabolic pathways.

Index-Based Assessment of Voltage Rise and Reverse Power Flow Phenomena in a Distribution Feeder Under High PV Penetration

DEFF Research Database (Denmark)

Hasheminamin, Maryam; Agelidis, Vassilios G.; Salehi, Vahid

2015-01-01

-based methodology for assessing the impact of high solar PV generation, considering the reverse power flow and voltage rise phenomena. Indices are defined that link these two phenomena and their impact on the voltage profile across the feeder. This assessment relies on detailed modeling of the network and the solar......The proliferation of photovoltaic (PV) generation in low- and medium-voltage distribution networks is expected to continue. Qualified studies can quantify adverse impacts of high PV penetration on distribution networks and assist utilities in decision making. This paper proposes an index...

A UHF RFID positioning system for use in warehouse navigation by employees with cognitive disability.

Science.gov (United States)

Gunther, Eric J M; Sliker, Levin J; Bodine, Cathy

2017-11-01

Unemployment among the almost 5 million working-age adults with cognitive disabilities in the USA is a costly problem in both tax dollars and quality of life. Job coaching is an effective tool to overcome this, but the cost of job coaching services sums with every new employee or change of employment roles. There is a need for a cost-effective, automated alternative to job coaching that incurs a one-time cost and can be reused for multiple employees or roles. An effective automated job coach must be aware of its location and the location of destinations within the job site. This project presents a design and prototype of a cart-mounted indoor positioning and navigation system with necessary original software using Ultra High Frequency Radio Frequency Identification (UHF RFID). The system presented in this project for use within a warehouse setting is one component of an automated job coach to assist in the job of order filler. The system demonstrated accuracy to within 0.3 m under the correct conditions with strong potential to serve as the basis for an effective indoor navigation system to assist warehouse workers with disabilities. Implications for rehabilitation An automated job coach could improve employability of and job retention for people with cognitive disabilities. An indoor navigation system using ultra high frequency radio frequency identification was proposed with an average positioning accuracy of 0.3 m. The proposed system, in combination with a non-linear context-aware prompting system, could be used as an automated job coach for warehouse order fillers with cognitive disabilities.

Brush-Painting and Photonic Sintering of Copper Oxide and Silver Inks on Wood and Cardboard Substrates to Form Antennas for UHF RFID Tags

Directory of Open Access Journals (Sweden)

Erja Sipilä

2016-01-01

Full Text Available Additive deposition of inks with metallic inclusions provides compelling means to embed electronics into versatile structures. The need to integrate electronics into environmentally friendly components and structures increases dramatically together with the increasing popularity of the Internet of Things. We demonstrate a novel brush-painting method for depositing copper oxide and silver inks directly on wood and cardboard substrates and discuss the optimization of the photonic sintering process parameters for both materials. The optimized parameters were utilized to manufacture passive ultra high frequency (UHF radio frequency identification (RFID tag antennas. The results from wireless testing show that the RFID tags based on the copper oxide and silver ink antennas on wood substrate are readable from ranges of 8.5 and 11 meters, respectively, and on cardboard substrate from read ranges of 8.5 and 12 meters, respectively. These results are well sufficient for many future wireless applications requiring remote identification with RFID.

47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. 25.250 Section 25.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25...

Feasibility assessment of optical technologies for reliable high capacity feeder links

Science.gov (United States)

Witternigg, Norbert; Schönhuber, Michael; Leitgeb, Erich; Plank, Thomas

2013-08-01

Space telecom scenarios like data relay satellite and broadband/broadcast service providers require reliable feeder links with high bandwidth/data rate for the communication between ground station and satellite. Free space optical communication (FSOC) is an attractive alternative to microwave links, improving performance by offering abundant bandwidth at small apertures of the optical terminals. At the same time Near-Earth communication by FSOC avoids interference with other services and is free of regulatory issues. The drawback however is the impairment by the laser propagation through the atmosphere at optical wavelengths. Also to be considered are questions of eye safety for ground personnel and aviation. In this paper we assess the user requirements for typical space telecom scenarios and compare these requirements with solutions using optical data links through the atmosphere. We suggest a site diversity scheme with a number of ground stations and a switching scheme using two optical terminals on-board the satellite. Considering the technology trade-offs between four different optical wavelengths we recommend the future use of 1.5 μm laser technology and calculate a link budget for an atmospheric condition of light haze on the optical path. By comparing link budgets we show an outlook to the future potential use of 10 μm laser technology.

An efficient hexagonal switched beam antenna structure based on Fabry-Perot cavity leaky-wave antenna

Science.gov (United States)

Aymen El Cafsi, Mohamed; Nedil, Mourad; Osman, Lotfi; Gharsallah, Ali

2015-11-01

A novel design of switched beam antenna (SBA) system based on Fabry-Perot cavity leaky-wave antenna (FPC LWA) is designed and fabricated for base station operating in the unlicensed ISM central frequency band at 5.8 GHz of the wireless local area network (WLAN) standard. The proposed SBA is designed with hexagonal shape of FPC LWA Arrays in order to get 360° of coverage. The single element of FPC LWA array is composed of a patch antenna and covered by a Partially Reflective Surface (PRS), which is composed of a Metal Strip Grating and printed on a high permittivity Superstrate. First, the Transmission Line Model of FPC LWA is introduced to analyse and calculate the far-field components in E- and H planes by using the Transverse Equivalent Network. This approach is then compared with other full wave's commercial software such as Ansoft HFSS and CST Microwave Studio. Second, a parametric study is performed to evaluate the effect of the angle formed by the two successive FPC LWA on the radiation efficiency of the activate sector. To examine the performance of the proposed SBA, experimental prototype was fabricated and measured. As a result, multiple orthogonal beams (six beams) of 10 dBi of gain with low Side Lobes Level and 360° of coverage are produced. This SBA structure is suitable for WLAN communication systems.

Guided-Mode-Leaky-Mode-Guided-Mode Fiber Interferometer and Its High Sensitivity Refractive Index Sensing Technology

Directory of Open Access Journals (Sweden)

Qi Wang

2016-06-01

Full Text Available A cascaded symmetrical dual-taper Mach-Zehnder interferometer structure based on guided-mode and leaky-mode interference is proposed in this paper. Firstly, the interference spectrum characteristics of interferometer has been analyzed by the Finite Difference-Beam Propagation Method (FD-BPM. When the diameter of taper waist is 20 μm–30 μm, dual-taper length is 1 mm and taper distance is 4 cm–6 cm, the spectral contrast is higher, which is suitable for sensing. Secondly, experimental research on refractive index sensitivity is carried out. A refractive index sensitivity of 62.78 nm/RIU (refractive index unit can achieved in the RI range of 1.3333–1.3792 (0%~25% NaCl solution, when the sensor structure parameters meet the following conditions: diameter of taper waist is 24 μm, dual-taper length is 837 μm and taper distance is 5.5 cm. The spectrum contrast is 0.8 and measurement resolution is 1.6 × 10−5 RIU. The simulation analysis is highly consistent with experimental results. Research shows that the sensor has promising application in low RI fields where high-precision measurement is required due to its high sensitivity and stability.

Changes in thunderstorm characteristics due to feeder cloud merging

Science.gov (United States)

Sinkevich, Andrei A.; Krauss, Terrence W.

2014-06-01

Cumulus cloud merging is a complex dynamical and microphysical process in which two convective cells merge into a single cell. Previous radar observations and numerical simulations have shown a substantial increase in the maximum area, maximum echo top and maximum reflectivity as a result of the merging process. Although the qualitative aspects of merging have been well documented, the quantitative effects on storm properties remain less defined. Therefore, a statistical assessment of changes in storm characteristics due to merging is of importance. Further investigation into the effects of cloud merging on precipitation flux (Pflux) in a statistical manner provided the motivation for this study in the Asir region of Saudi Arabia. It was confirmed that merging has a strong effect on storm development in this region. The data analysis shows that an increase in the median of the distribution of maximum reflectivity was observed just after merging and was equal to 3.9 dBZ. A detailed analysis of the individual merge cases compared the merged storm Pflux and mass to the sum of the individual Feeder and Storm portions just before merging for each case. The merged storm Pflux increased an average of 106% over the 20-min period after merging, and the mass increased on average 143%. The merged storm clearly became larger and more severe than the sum of the two parts prior to merging. One consequence of this study is that any attempts to evaluate the precipitation enhancement effects of cloud seeding must also include the issue of cloud mergers because merging can have a significant effect on the results.

Real-time modeling and simulation of distribution feeder and distributed resources

Science.gov (United States)

Singh, Pawan

The analysis of the electrical system dates back to the days when analog network analyzers were used. With the advent of digital computers, many programs were written for power-flow and short circuit analysis for the improvement of the electrical system. Real-time computer simulations can answer many what-if scenarios in the existing or the proposed power system. In this thesis, the standard IEEE 13-Node distribution feeder is developed and validated on a real-time platform OPAL-RT. The concept and the challenges of the real-time simulation are studied and addressed. Distributed energy resources include some of the commonly used distributed generation and storage devices like diesel engine, solar photovoltaic array, and battery storage system are modeled and simulated on a real-time platform. A microgrid encompasses a portion of an electric power distribution which is located downstream of the distribution substation. Normally, the microgrid operates in paralleled mode with the grid; however, scheduled or forced isolation can take place. In such conditions, the microgrid must have the ability to operate stably and autonomously. The microgrid can operate in grid connected and islanded mode, both the operating modes are studied in the last chapter. Towards the end, a simple microgrid controller modeled and simulated on the real-time platform is developed for energy management and protection for the microgrid.

Abnormalities of thymic stroma may contribute to immune dysregulation in murine models of leaky severe combined immunodeficiency

Directory of Open Access Journals (Sweden)

Francesca eRucci

2011-05-01

Full Text Available Lymphostromal cross-talk in the thymus is essential to allow generation of a diversified repertoire of T lymphocytes and to prevent autoimmunity by self-reactive T cells. Hypomorphic mutations in genes that control T cell development have been associated with immunodeficiency and immune dysregulation both in humans and in mice. We have studied T cell development and thymic stroma architecture and maturation in two mouse models of leaky SCID, carrying hypomorphic mutations in Rag1 and Lig4 genes. Defective T cell development was associated with abnormalities of thymic architecture that predominantly affect the thymic medulla, with reduction of the pool of mature medullary thymic epithelial cells (mTECs. While the ability of mTECs to express Aire is preserved in mutant mice, the frequency of mature mTECs expressing Aire and tissue-specific antigens (TSAs is severely reduced. Similarly, the ability of CD4+ T cells to differentiate into Foxp3+ natural regulatory T cells is preserved in Rag1 and Lig4 mutant mice, but their number is greatly reduced. These data indicate that hypomorphic defects in T cell development may cause defective lymphostromal cross-talk and impinge on thymic stromal cells maturation, and thus favor immune dysregulation.

Comparisons of benthic filter feeder communities before and after a large-scale capital dredging program.

Science.gov (United States)

Abdul Wahab, Muhammad Azmi; Fromont, Jane; Gomez, Oliver; Fisher, Rebecca; Jones, Ross

2017-09-15

Changes in turbidity, sedimentation and light over a two year large scale capital dredging program at Onslow, northwestern Australia, were quantified to assess their effects on filter feeder communities, in particular sponges. Community functional morphological composition was quantified using towed video surveys, while dive surveys allowed for assessments of species composition and chlorophyll content. Onslow is relatively diverse recording 150 sponge species. The area was naturally turbid (1.1 mean P 80 NTU), with inshore sites recording 6.5× higher turbidity than offshore localities, likely influenced by the Ashburton River discharge. Turbidity and sedimentation increased by up to 146% and 240% through dredging respectively, with corresponding decreases in light levels. The effects of dredging was variable, and despite existing caveats (i.e. bleaching event and passing of a cyclone), the persistence of sponges and the absence of a pronounced response post-dredging suggest environmental filtering or passive adaptation acquired pre-dredging may have benefited these communities. Copyright © 2017. Published by Elsevier Ltd.

Comparative bioaccumulation of trace metals using six filter feeder organisms in a coastal lagoon ecosystem (of the central-east Gulf of California).

Science.gov (United States)

Jara-Marini, M E; Tapia-Alcaraz, J N; Dumer-Gutiérrez, J A; García-Rico, L; García-Hernández, J; Páez-Osuna, F

2013-02-01

The Tobari Lagoon, located in the central-east coast of the Gulf of California, receives effluents from the Yaqui Valley, one of the most extensive agricultural areas of México. The Tobari Lagoon also receives effluents from nearby shrimp farms and untreated municipal sewage. Surface sediment samples and six different species of filter feeders (Crassostrea corteziensis, Crassostrea gigas, Chione gnidia, Anadara tuberculosa, Chione fluctifraga, and Fistulobalanus dentivarians) were collected during the dry and the rainy seasons and analyzed to determine concentrations of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn). Seasonal variations in metal concentrations in sediment were evident, especially for Cd, Cu, Hg, and Zn. The total and bioavailable concentrations of the five metals are not elevated in comparison to other areas around the world. The percentages of bioavailable respect to total concentrations of the metals varied from 0.6 % in Hg to 50.2 % for Cu. In the organisms, Hg showed the lowest concentrations (ranged from 0.22 to 0.65 μg/g) while Zn showed the highest (ranged from 36.6 to 1,702 μg/g). Linear correlations between the levels of Cu, Pb, and Zn in the soft tissues of C. fluctifraga and C. gnidia, and A. tuberculosa and C. gnidia were found. Seasonal and interspecies variations in the metal levels in filter feeders were found; F. dentivarians, C. corteziensis, and C. gigas exhibited the highest levels, could be used as biomonitors of metals contamination in this area.

Toward cardiovascular MRI at 7 T: clinical needs, technical solutions and research promises

International Nuclear Information System (INIS)

Niendorf, Thoralf; Sodickson, Daniel K.; Krombach, Gabriele A.; Schulz-Menger, Jeanette

2010-01-01

To consider potential clinical needs, technical solutions and research promises of ultrahigh-field strength cardiovascular MR (CMR). A literature review is given, surveying advantages and disadvantages of CMR at ultrahigh fields (UHF). Key concepts, emerging technologies, practical considerations and applications of UHF CMR are provided. Examples of UHF CMR imaging strategies and their added value are demonstrated, including the numerous unsolved problems. A concluding section explores future directions in UHF CMR. UHF CMR can be regarded as one of the most challenging MRI applications. Image quality achievable at UHF is not always exclusively defined by signal-to-noise considerations. Some of the inherent advantages of UHF MRI are offset by practical challenges. But UHF CMR can boast advantages over its kindred lower field counterparts by trading the traits of high magnetic fields for increased temporal and/or spatial resolution. CMR at ultrahigh-field strengths is a powerful motivator, since speed and signal may be invested to overcome the fundamental constraints that continue to hamper traditional CMR. If practical challenges can be overcome, UHF CMR will help to open the door to new approaches for basic science and clinical research. (orig.)

Navy Network Dependability: Models, Metrics, and Tools

Science.gov (United States)

2010-01-01

surveillance; TCDL = Tactical Common Data Link; UHF = ultra high frequency; UFO = ultra-high-frequency follow-on; WGS = Wideband Gapfiller Satellite. RAND...VOICE (DMR VALUES) UFO OE-82 UHF LOS VOICE (DMR VALUES) UHF SATCOM VOICE DMR UHF LOS VOICE DMR TVs ADMS KIV-7 COMSEC ADNS SW ADNS II HW ISNS SW ISNS HW...Data Link; UHF = ultra high frequency; UFO = ultra-high-frequency follow-on; WGS = Wideband Gapfiller Satellite. RAND MG1003-1.1 4 Navy Network

The Cost of Distribution System Upgrades to Accommodate Increasing Penetrations of Distributed Photovoltaic Systems on Real Feeders in the United States

Energy Technology Data Exchange (ETDEWEB)

Horowitz, Kelsey A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ding, Fei [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mather, Barry A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Palmintier, Bryan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-04-05

The increasing deployment of distributed photovoltaic systems (DPV) can impact operations at the distribution level and the transmission level of the electric grid. It is important to develop and implement forward-looking approaches for calculating distribution upgrade costs that can be used to inform system planning, market and tariff design, cost allocation, and other policymaking as penetration levels of DPV increase. Using a bottom-up approach that involves iterative hosting capacity analysis, this report calculates distribution upgrade costs as a function of DPV penetration on three real feeders - two in California and one in the Northeastern United States.

U.S. safety legislation a bonanza for suppliers

Energy Technology Data Exchange (ETDEWEB)

Tollinsky, N.

2007-09-01

New safety requirements for coal mines in the United States requires the installation of wireless two-way tracking systems. The Office of Miners' Health Safety and Training has demanded that the owners of West Virginia's 170 coal mines submit plans by July 31, 2007 that describe how and when they intend to procure communication and electonic tracking systems. An estimated 430 additional coal mines across the U.S. will be required to file their plans concerning communications and tracking equipment by June 15, 2009, according to the U.S. federal government's Mine Improvement and New Emergency Response (MINER) Act. Radio communication and leaky feeder systems are routine in Canada's hard rock mines. Several Ontario-based supply companies are well placed to take advantage of this opportunity. The plans of three Ontario suppliers regarding proposed communications systems, quotations, costs, and tracking are outlined. 3 figs.

Leaky RAG Deficiency in Adult Patients with Impaired Antibody Production against Bacterial Polysaccharide Antigens.

Directory of Open Access Journals (Sweden)

Christoph B Geier

Full Text Available Loss of function mutations in the recombination activating genes RAG1 and RAG2 have been reported to cause a T-B-NK+ type of severe combined immunodeficiency. In addition identification of hypomorphic mutations in RAG1 and RAG2 has led to an expansion of the spectrum of disease to include Omenn syndrome, early onset autoimmunity, granuloma, chronic cytomegalovirus- or EBV-infection with expansion of gamma/delta T-cells, idiophatic CD4 lymphopenia and a phenotype resembling common variable immunodeficiency. Herein we describe a novel presentation of leaky RAG1 and RAG2 deficiency in two unrelated adult patients with impaired antibody production against bacterial polysaccharide antigens. Clinical manifestation included recurrent pneumonia, sinusitis, otitis media and in one patient recurrent cutaneous vasculitis. Both patients harbored a combination of a null mutation on one allele with a novel hypomorphic RAG1/2 mutation on the other allele. One of these novel mutations affected the start codon of RAG1 and resulted in an aberrant gene and protein expression. The second novel RAG2 mutation leads to a truncated RAG2 protein, lacking the C-terminus with intact core RAG2 and reduced VDJ recombination capacity as previously described in a mouse model. Both patients presented with severely decreased numbers of naïve CD4+ T cells and defective T independent IgG responses to bacterial polysaccharide antigens, while T cell-dependent IgG antibody formation e.g. after tetanus or TBEV vaccination was intact. In conclusion, hypomorphic mutations in genes responsible for SCID should be considered in adults with predominantly antibody deficiency.

The SYOEKSY research project. Electrically-powered vehicles in ring rail line feeder traffic and short-distance travel; Saehkoeiset ajoneuvot kehaeradan syoettoe- ja asiointiliikenteessae. SYOEKSY-tutkimushankkeen loppuraportti 21.9.2011

Energy Technology Data Exchange (ETDEWEB)

2011-07-01

The research report is divided into three sections: a general description of the project, separate reports on each of the themes investigated and a summary of the research results and recommendations. Section 2 deals with themes such as: Low-emissions-technology solutions for traffic and their technical prerequisites in an urban environment and the results obtained from pilot projects. New service models based on electrically-powered traffic technology with an assessment of their feasibility and their effect on urban infrastructure and levels of CO{sub 2} emissions. User needs in new feeder traffic, short-distance travel and other journeys on personal business together with proposals for planning measures which will promote sustainable mobility in new residential areas. The prerequisites for electrically-powered feeder traffic and short-distance travel are therefore handled in a wide-ranging manner. A condensed version of the project conclusions and recommendations is provided in Section 3. A list of the data sources and publications resulting from project work can be found at the end of the report

Fractional-order leaky integrate-and-fire model with long-term memory and power law dynamics.

Science.gov (United States)

Teka, Wondimu W; Upadhyay, Ranjit Kumar; Mondal, Argha

2017-09-01

Pyramidal neurons produce different spiking patterns to process information, communicate with each other and transform information. These spiking patterns have complex and multiple time scale dynamics that have been described with the fractional-order leaky integrate-and-Fire (FLIF) model. Models with fractional (non-integer) order differentiation that generalize power law dynamics can be used to describe complex temporal voltage dynamics. The main characteristic of FLIF model is that it depends on all past values of the voltage that causes long-term memory. The model produces spikes with high interspike interval variability and displays several spiking properties such as upward spike-frequency adaptation and long spike latency in response to a constant stimulus. We show that the subthreshold voltage and the firing rate of the fractional-order model make transitions from exponential to power law dynamics when the fractional order α decreases from 1 to smaller values. The firing rate displays different types of spike timing adaptation caused by changes on initial values. We also show that the voltage-memory trace and fractional coefficient are the causes of these different types of spiking properties. The voltage-memory trace that represents the long-term memory has a feedback regulatory mechanism and affects spiking activity. The results suggest that fractional-order models might be appropriate for understanding multiple time scale neuronal dynamics. Overall, a neuron with fractional dynamics displays history dependent activities that might be very useful and powerful for effective information processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

From leaky pipeline to irrigation system: minority education through the lens of community-based participatory research.

Science.gov (United States)

James, Rosalina; Starks, Helene; Segrest, Valerie Ann; Burke, Wylie

2012-01-01

Higher education has long made efforts to increase underrepresented minority participation in biomedical research and health fields. However, relatively few minority trainees complete advanced degrees or proceed to independent research careers, a loss referred to as the "leaky pipeline." Minority trainees may take alternate pathways to climbing the academic ladder, exiting to pursue multiple disciplinary or community-serving roles. The authors propose a model for understanding minority departures from the education pipeline as a basis for supporting careers that align with community goals for health. Concepts of the traditional pipeline training model are compared with a model that aligns with community-based participatory research (CBPR) principles and practices. The article describes an irrigation model that incorporates informal learning from academic and community knowledge bases to prepare trainees for CBPR and interdisciplinary research. Students serve as agents that foster individual, institutional, and social change needed to address health problems while attending to root causes of disparities. Viewing minority students as agents for community engagement allows institutions to reassess the role training can play in diversifying participation in higher education and research. An irrigation model supports development of an infrastructure that optimizes success at all post-secondary levels, and enhances CBPR capacity wherever trainees live, work, and learn. Linking formal education to informal learning in context of CBPR experiences can also reduce community mistrust of research while nurturing productive research partnerships with communities to address health disparities.

Substrate-Integrated Waveguide PCB Leaky-Wave Antenna Design Providing Multiple Steerable Beams in the V-Band

Directory of Open Access Journals (Sweden)

Matthias Steeg

2017-12-01

Full Text Available A periodic leaky-wave antenna (LWA design based on low loss substrate-integrated waveguide (SIW technology with inset half-wave microstrip antennas is presented. The developed LWA operates in the V-band between 50 and 70 GHz and has been fabricated using standard printed circuit board (PCB technology. The presented LWA is highly functional and very compact supporting 1D beam steering and multibeam operation with only a single radio frequency (RF feeding port. Within the operational 50–70 GHz bandwidth, the LWA scans through broadside, providing over 40° H-plane beam steering. When operated within the 57–66 GHz band, the maximum steering angle is 18.2°. The maximum gain of the fabricated LWAs is 15.4 dBi with only a small gain variation of +/−1.5 dB across the operational bandwidth. The beam steering and multibeam capability of the fabricated LWA is further utilized to support mobile users in a 60 GHz hot-spot. For a single user, a maximum wireless on-off keying (OOK data rate of 2.5 Gbit/s is demonstrated. Multibeam operation is achieved using the LWA in combination with multiple dense wavelength division multiplexing (WDM channels and remote optical heterodyning. Experimentally, multibeam operation supporting three users within a 57–66 GHz hot-spot with a total wireless cell capacity of 3 Gbit/s is achieved.

Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture; Cultivo e irradiacao de fibroblastos humanos em meio enriquecido com lisado de plaquetas para obtencao de camada de sustentacao em culturas de celulas da epiderme

Energy Technology Data Exchange (ETDEWEB)

Yoshito, Daniele

2011-07-01

For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

Manufacture and test of seismic bellows for ITER magnet feeder

International Nuclear Information System (INIS)

Liu, Chen; Lu, Kun; Sheng, Liang; Song, Yuntao; Su, Jinjin; Su, Man; Gung, Chenyu

2016-01-01

Highlights: • The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. • The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. • 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. • A full tensile test with 315 mm of stretching from its nominal length was conducted. • The prototype bellows was qualified for its leak tightness (less than 1 × 10 −9 Pam 3 /s of helium) at all time during the qualification test. - Abstract: This paper presents the key manufacturing and testing processes of the prototype ITER feeder seismic bellows. The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. Each inner and outer bellows was supported in dedicated molds and formed by a hydraulic pressure machine rated at 800 tons. The double bellows were constructed by welding individual collars to the end flanges. The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. This was followed by 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. After the mechanical fatigue test, a full tensile test with 315 mm of stretching from its nominal length was conducted. Helium leak tests, with the sensitivity of the helium leak detector set to 1 × 10 −9 Pa m 3 /s of helium, were performed at different stages of pressure and mechanical tests. The prototype bellows was qualified for its leak tightness at all time during the qualification test.

Manufacture and test of seismic bellows for ITER magnet feeder

Energy Technology Data Exchange (ETDEWEB)

Liu, Chen, E-mail: liuchen@ipp.ac.cn [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Lu, Kun [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Sheng, Liang [AEROSUN-TOLA Expansion Joint Co., Ltd., Jiangjun Road No. 199, Nanjing (China); Song, Yuntao; Su, Jinjin [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Su, Man; Gung, Chenyu [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul-lez-Durance (France)

2016-11-01

Highlights: • The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. • The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. • 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. • A full tensile test with 315 mm of stretching from its nominal length was conducted. • The prototype bellows was qualified for its leak tightness (less than 1 × 10{sup −9} Pam{sup 3}/s of helium) at all time during the qualification test. - Abstract: This paper presents the key manufacturing and testing processes of the prototype ITER feeder seismic bellows. The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. Each inner and outer bellows was supported in dedicated molds and formed by a hydraulic pressure machine rated at 800 tons. The double bellows were constructed by welding individual collars to the end flanges. The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. This was followed by 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. After the mechanical fatigue test, a full tensile test with 315 mm of stretching from its nominal length was conducted. Helium leak tests, with the sensitivity of the helium leak detector set to 1 × 10{sup −9} Pa m{sup 3}/s of helium, were performed at different stages of pressure and mechanical tests. The prototype bellows was qualified for its leak tightness at all time during the qualification test.

Positioning systems for underground tunnel environments

CERN Document Server

Leite Pereira, Fernando; Theis, Christian

In the last years the world has witnessed a remarkable change in the computing concept by entering the mobile era. Incredibly powerful smartphones have proliferated at stunning pace and tablet computers are capable of running demanding applications and meet new business requirements. Being wireless, localization has become crucial not only to serve individuals but also help companies in industrial and safety processes. In the context of the Radiation Protection group at CERN, automatic localization, besides allowing to find people, would help improving the radiation surveys performed regularly along the accelerator tunnels. The research presented in this thesis attempts to answer questions relatively to the viability of localization in a harsh conditions tunnel: “Is localization in a very long tunnel possible, meeting its restrictions and without incurring prohibitive costs and infrastructure?”, “Can one achieve meter-level accuracy with GSM deployed over leaky-feeder?”, “Is it possible to prototype...

Easy xeno-free and feeder-free method for isolating and growing limbal stromal and epithelial stem cells of the human cornea.

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Djida Ghoubay-Benallaoua

Full Text Available Epithelial and stromal stem cells are required to maintain corneal transparency. The aim of the study was to develop a new method to isolate and grow both corneal stromal (SSC and epithelial limbal (LSC stem cells from small human limbal biopsies under culture conditions in accordance with safety requirements mandatory for clinical use in humans. Superficial limbal explants were retrieved from human donor corneo-scleral rims. Human limbal cells were dissociated by digestion with collagenase A, either after epithelial scraping or with no scraping. Isolated cells were cultured with Essential 8 medium (E8, E8 supplemented with EGF (E8+ or Green's medium with 3T3 feeder-layers. Cells were characterized by immunostaining, RT-qPCR, colony forming efficiency, sphere formation, population doubling, second harmonic generation microscopy and differentiation potentials. LSC were obtained from unscraped explants in E8, E8+ and Green's media and were characterized by colony formation and expression of PAX6, ΔNP63α, Bmi1, ABCG2, SOX9, CK14, CK15 and vimentin, with a few cells positive for CK3. LSC underwent 28 population doublings still forming colonies. SSC were obtained from both scraped and unscraped explants in E8 and E8+ media and were characterized by sphere formation, expression of PAX6, SOX2, BMI1, NESTIN, ABCG2, KERATOCAN, VIMENTIN, SOX9, SOX10 and HNK1, production of collagen fibrils and differentiation into keratocytes, fibroblasts, myofibroblasts, neurons, adipocytes, chondrocytes and osteocytes. SSC underwent 48 population doublings still forming spheres, Thus, this new method allows both SSC and LSC to be isolated from small superficial limbal biopsies and to be primary cultured in feeder-free and xeno-free conditions, which will be useful for clinical purposes.

Investigation of inertia-gravity waves in the upper troposphere/lower stratosphere over Northern Germany observed with collocated VHF/UHF radars

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A. Serafimovich

2005-01-01

Full Text Available A case study to investigate the properties of inertia-gravity waves in the upper troposphere/lower stratosphere has been carried out over Northern Germany during the occurrence of an upper tropospheric jet in connection with a poleward Rossby wave breaking event from 17-19 December 1999. The investigations are based on the evaluation of continuous radar measurements with the OSWIN VHF radar at Kühlungsborn (54.1 N, 11.8 E and the 482 MHz UHF wind profiler at Lindenberg (52.2 N, 14.1 E. Both radars are separated by about 265 km. Based on wavelet transformations of both data sets, the dominant vertical wavelengths of about 2-4 km for fixed times as well as the dominant observed periods of about 11 h and weaker oscillations with periods of  6 h for the altitude range between 5 and 8 km are comparable. Gravity wave parameters have been estimated at both locations separately and by a complex cross-spectral analysis of the data of both radars. The results show the appearance of dominating inertia-gravity waves with characteristic horizontal wavelengths of  300 km moving in the opposite direction than the mean background wind and a secondary less pronounced wave with a horizontal wavelength in the order of about 200 km moving with the wind. Temporal and spatial differences of the observed waves are discussed.

Electromagnetic fields (UHF) increase voltage sensitivity of membrane ion channels; possible indication of cell phone effect on living cells.

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Ketabi, N; Mobasheri, H; Faraji-Dana, R

2015-03-01

The effects of ultra high frequency (UHF) nonionizing electromagnetic fields (EMF) on the channel activities of nanopore forming protein, OmpF porin, were investigated. The voltage clamp technique was used to study the single channel activity of the pore in an artificial bilayer in the presence and absence of the electromagnetic fields at 910 to 990 MHz in real time. Channel activity patterns were used to address the effect of EMF on the dynamic, arrangement and dielectric properties of water molecules, as well as on the hydration state and arrangements of side chains lining the channel barrel. Based on the varied voltage sensitivity of the channel at different temperatures in the presence and absence of EMF, the amount of energy transferred to nano-environments of accessible groups was estimated to address the possible thermal effects of EMF. Our results show that the effects of EMF on channel activities are frequency dependent, with a maximum effect at 930 MHz. The frequency of channel gating and the voltage sensitivity is increased when the channel is exposed to EMF, while its conductance remains unchanged at all frequencies applied. We have not identified any changes in the capacitance and permeability of membrane in the presence of EMF. The effect of the EMF irradiated by cell phones is measured by Specific Absorption Rate (SAR) in artificial model of human head, Phantom. Thus, current approach applied to biological molecules and electrolytes might be considered as complement to evaluate safety of irradiating sources on biological matter at molecular level.

Consolidated Ground Segment Requirements for a UHF Radar for the ESSAS

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Muller, Florent; Vera, Juan

2009-03-01

ESA has launched a nine months long study to define the requirements associated to the ground segment of a UHF (300-3000 MHz) radar system. The study has been awarded in open competition to a consortium led by Onera, associated to the Spanish companies Indra and its sub-contractor Deimos. After a phase of consolidation of the requirements, different monostatic and bistatic concepts of radars will be proposed and evaluated. Two concepts will be selected for further design studies. ESA will then select the best one, for detailed design as well as cost and performance evaluation. The aim of this paper is to present the results of the first phase of the study concerning the consolidation of the radar system requirements. The main mission for the system is to be able to build and maintain a catalogue of the objects in low Earth orbit (apogee lower than 2000km) in an autonomous way, for different sizes of objects, depending on the future successive development phases of the project. The final step must give the capability of detecting and tracking 10cm objects, with a possible upgrade to 5 cm objects. A demonstration phase must be defined for 1 m objects. These different steps will be considered during all the phases of the study. Taking this mission and the different steps of the study as a starting point, the first phase will define a set of requirements for the radar system. It was finished at the end of January 2009. First part will describe the constraints derived from the targets and their environment. Orbiting objects have a given distribution in space, and their observability and detectability are based on it. It is also related to the location of the radar system But they are also dependant on the natural propagation phenomenon, especially ionospheric issues, and the characteristics of the objects. Second part will focus on the mission itself. To carry out the mission, objects must be detected and tracked regularly to refresh the associated orbital parameters

An Intelligent Sensor for the Ultra-High-Frequency Partial Discharge Online Monitoring of Power Transformers

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Jian Li

2016-05-01

Full Text Available Ultra-high-frequency (UHF partial discharge (PD online monitoring is an effective way to inspect potential faults and insulation defects in power transformers. The construction of UHF PD online monitoring system is a challenge because of the high-frequency and wide-frequency band of the UHF PD signal. This paper presents a novel, intelligent sensor for UHF PD online monitoring based on a new method, namely a level scanning method. The intelligent sensor can directly acquire the statistical characteristic quantities and is characterized by low cost, few data to output and transmit, Ethernet functionality, and small size for easy installation. The prototype of an intelligent sensor was made. Actual UHF PD experiments with three typical artificial defect models of power transformers were carried out in a laboratory, and the waveform recording method and intelligent sensor proposed were simultaneously used for UHF PD measurement for comparison. The results show that the proposed intelligent sensor is qualified for the UHF PD online monitoring of power transformers. Additionally, three methods to improve the performance of intelligent sensors were proposed according to the principle of the level scanning method.

Comparison of the Ex Vivo Expansion of UCB-Derived CD34+ in 3D DBM/MBA Scaffolds with USSC as a Feeder Layer.

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Sadat Hashemi, Zahra; Forouzandeh Moghadam, Mahdi; Soleimani, Masoud

2013-10-01

Ex vivo expansion of hematopoitic stem cells is an alternative way to increase umbilical cord blood (UCB)-CD34+ cells for bone marrow transplantation. For this purpose demineralized bone matrix (DBM) and mineralized bone allograft (MBA) as two scaffolds based on bone matrix and stem cell niche, were simultaneously used to enhance the effect of human mesenchymal progenitor cells (MPCs) - unrestricted somatic stem cells (USSCs) - as a feeder layer. USSCs were isolated and characterized by morphological and immunological analysis then seeded on both scaffolds as a feeder layer. UCB-CD34(+) were isolated by MACS method and were co-culture expanded by USSC in 3D and 2D environments. After 3 weeks expansion, cells were counted and were assessed by karyotype, flow cytometry, clonogenic activity, and long-term culture-initiating cells (LTC-IC). Co-culture expansion in DBM and MBA was 29.22-fold and 27.77-fold, no significant differences in colony and LTC-IC were obtained. Maximum number of colonies belonged to the day 14 with the 73% CFU-GM (Colony Forming Unit- Granulocyte/Macrophage) in contrast to the day 0 which was BFU-E/CFU-E (Burst/Colony Forming Unit-Erythroid). Flow cytometry indicated that the percentage of CD34+ marker was decreased in USSC co-culture and the highest percentage was observed in simple 2D culture. Because of acid extraction in the DBM production process, mineral materials were removed and the protein background that was more flexible was presented. Therefore these results suggest that USSC-DBM can be a suitable ex vivo mimicry niche by intensifying of surface/volume ratio and supporting the stem cell differentiation and expansion.