WorldWideScience

Sample records for voltage drainage experiment

  1. Comparative experiments of gas drainage in different types of drillings

    Institute of Scientific and Technical Information of China (English)

    LI Cheng-wu; WEI Shan-yang; WANG Chuan; GAO Tian-bao; FU Yu-kai

    2012-01-01

    Gas drainage effect is the utmost important factor for mining speed and mining safety.It has great meaning to study the effect of gas drainage.Comparative experiment of gas drainage in different types of drillings shows that the initial rate of gas natural emission by hydraulic loosed cross drilling is 1.5 times more than that of parallel drilling,and the drilling gas attenuation coefficients reduces to 0.78 times,the effect of gas drainage is good.The ultimate quantity of gas drainage of parallel drilling,cross drilling,hydraulic loosed cross drilling are 859.1,1 323.5 and 1 833.6 m3/100 m.The results of the measurement through these three kinds of drillings of 100 meters drilling is considered as following:cross drilling is 1.54 times more than that of parallel drillings,hydraulic loosed cross drilling are 2.13 times more than parallel drilling.The drainage rate of parallel drilling,cross drilling and hydraulic loosed cross drilling reached 10% to 15% in 3 months with the pre-draining time.Among these,the drainage effect of hydraulic loosed cross drilling increased by 46% than that of parallel drilling in three months.

  2. Reproducible and controllable induction voltage adder for scaled beam experiments

    Science.gov (United States)

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko

    2016-08-01

    A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments.

  3. Ultrasound-guided percutaneous transhepatic biliary drainage: Experiences in 146 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jai Keun [Sohwa Children' s Hospital, Seoul(Korea, Republic of); Yu, Jeong Sik; Kim, Ki Whang; Chung, Soo Yoon; Jeong, Mi Gyoung [Yonsei University College of Medicine, Seoul (Korea, Republic of); Choi, Deuk Lin; Kwon, Gui Hyang; Lee, Hae Kyung [Soonchunhyang University College of Medicine, Seoul (Korea, Republic of)

    1999-03-15

    Percutaneous biliary drainage is an important technique for palliative therapy of obstructive biliary disease and diagnostic information. The purpose of this study is to review and evaluate the experiences of ultrasound-guided percutaneous transhepatic biliary drainage. Ultrasound-guided percutaneous transhepatic biliary drainage was performed on 146 occasions in 134 patients. The causes of biliary obstruction were: benign diseases (19 cases, 14.2%) such as bile duct stones or stricture, cholangiocarcinoma (37 cases, 27.6%), pancreatic carcinoma (35 cases, 26.1%), metastasis (22 cases, 16.5%), gall bladder cancer (14 cases, 10.4%), ampulla of Vater cancer (4 cases, 3.0%), hepatocellular carcinoma (3 cases, 2.2%). Retrospectively reviewing medical records, we found out frequency of external or external/internal biliary drainages, puncture of left or right hepatic duct, and presence of bileinfection. Ultrasound-guided percutaneous transhepatic biliary drainage was compared with conventional biliary drainage of previous reports on the basis of frequency of complications. External (124 procedures, 84.9%) and external/internal biliary drainage (22 procedures, 15.1%) were carried out by puncture of dilated right (59.6%) or left (40.4%) intrahepatic duct. Sixty-nine complications occurred in 47 patients. Catheter related complications (33/69, 47.8%) were most common: catheter dislodgement (17/69, 24.6%), malfunction (9/69, 13.1%), leakage (7/69, 10.1%). Other minor complications such as simple fever (16/69, 23.2%), cholangitis (7/69, 10.1%), hemobilia (4/69, 5.8%), biloma (2/69, 2.9%) and wound infection (1/69, 1.5%) occurred. Major complications including sepsis (4/69, 5.8%) and bile peritonitis (2/69, 2.9%) were also noted. Puncture-related complications such as hemobilia, biloma and bile peritonitis occurred in 8 cases (5.5%). Comparing with conventional X-ray guided drainage, ultrasound-guided percutaneous transhepatic biliary drainage is a safe procedure for

  4. Operating Experiences of a Loss of Voltage Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun-Chan [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2015-10-15

    Loss of voltage (LOV) events continue to occur due to inadequate work management and random human errors. On February 26, 2015, regulators analyzed the root causes of LOV events and presented the results for the nuclear industry. Currently, KHNP uses a risk monitoring program, which is named 'LOV Monitor', for LOV prevention during pilot plant outages. This review introduces the operation experiences of LOV Monitor based on the evaluation results of a real event. The operation experiences of LOV Monitor in the pilot plants confirmed that this program could detect and reduce LOV possibilities from scheduling errors such as the simultaneous maintenance of energized trains and de-energized trains considering the physical conditions of the power circuit breakers. However, a maintenance culture that heeds the risk monitoring result must be strengthened in order to obtain substantial effects through applying LOV Monitor to the outage.

  5. An initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery

    Science.gov (United States)

    Costa, Altair da Silva; Bachichi, Thiago; Holanda, Caio; Rizzo, Luiz Augusto Lucas Martins De

    2016-01-01

    ABSTRACT Objective: To report an initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery. Methods: This was a prospective observational study involving consecutive patients, ≤ 14 years of age, treated at a pediatric thoracic surgery outpatient clinic, for whom pulmonary resection (lobectomy or segmentectomy via muscle-sparing thoracotomy) was indicated. The parameters evaluated were air leak (as quantified with the digital system), biosafety, duration of drainage, length of hospital stay, and complications. The digital system was used in 11 children (mean age, 5.9 ± 3.3 years). The mean length of hospital stay was 4.9 ± 2.6 days, the mean duration of drainage was 2.5 ± 0.7 days, and the mean drainage volume was 270.4 ± 166.7 mL. The mean maximum air leak flow was 92.78 ± 95.83 mL/min (range, 18-338 mL/min). Two patients developed postoperative complications (atelectasis and pneumonia, respectively). The use of this digital system facilitated the decision-making process during the postoperative period, reducing the risk of errors in the interpretation and management of air leaks. PMID:28117476

  6. The supply voltage apparatus of the CUORE experiment

    Science.gov (United States)

    Arnaboldi, C.; Baú, A.; Carniti, P.; Cassina, L.; Giachero, A.; Gotti, C.; Maino, M.; Passerini, A.; Pessina, G.

    2016-07-01

    The Electronics system of experiments for the study of rare decays, such as the neutrino-less double beta decay, must be very stable over very long expected runs. We introduce our solution for the power supply of such an experiment, CUORE. In this case the power supply chain consists of a series of ACDCs, followed by DCDCs and then Linear Regulators. We emphasize here our approach to the DCDC regulation system that was designed with a complete rejection of the switching noise, across 100 MHz bandwidth. In the experimental layout the DCDC will be located far from the very front-end, with long connecting cables (10 m). We introduced our very simple and safe solution to prevent huge over-voltages, due to the energy stored in the inductance of the cables, generated after the release of accidental short circuits, so avoiding destructive effects. Some micro-controllers are present on every board and take care of the DCDC operation. These micro-controllers are managed from the control room, via CAN BUS protocol coupled via optical fibres. CUORE is an array of 1000 cryogenic detectors that will need 30 of our DCDCs.

  7. The supply voltage apparatus of the CUORE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Arnaboldi, C.; Baú, A.; Carniti, P.; Cassina, L.; Giachero, A.; Gotti, C.; Maino, M.; Passerini, A. [INFN, Sezione di Milano Bicocca - Istituto Nazionale di Fisica Nucleare, Piazza della Scienza 3 Milano (Italy); Università di Milano Bicocca - Dipartimento di Fisica, Piazza della Scienza 3 Milano (Italy); Pessina, G., E-mail: Pessina@mib.infn.it [INFN, Sezione di Milano Bicocca - Istituto Nazionale di Fisica Nucleare, Piazza della Scienza 3 Milano (Italy); Università di Milano Bicocca - Dipartimento di Fisica, Piazza della Scienza 3 Milano (Italy)

    2016-07-11

    The Electronics system of experiments for the study of rare decays, such as the neutrino-less double beta decay, must be very stable over very long expected runs. We introduce our solution for the power supply of such an experiment, CUORE. In this case the power supply chain consists of a series of ACDCs, followed by DCDCs and then Linear Regulators. We emphasize here our approach to the DCDC regulation system that was designed with a complete rejection of the switching noise, across 100 MHz bandwidth. In the experimental layout the DCDC will be located far from the very front-end, with long connecting cables (10 m). We introduced our very simple and safe solution to prevent huge over-voltages, due to the energy stored in the inductance of the cables, generated after the release of accidental short circuits, so avoiding destructive effects. Some micro-controllers are present on every board and take care of the DCDC operation. These micro-controllers are managed from the control room, via CAN BUS protocol coupled via optical fibres. CUORE is an array of 1000 cryogenic detectors that will need 30 of our DCDCs.

  8. P Fractions in Drainage Waters from the Broadbalk Continuous Wheat Experiment at Rothamsted

    Institute of Scientific and Technical Information of China (English)

    L(ú) Jia-Long; S.FORTUNE; P.BROOKES

    2004-01-01

    Total P (TP),total particulate P (PP),total dissolved P (TDP),molybdate reactive P (MRP) and dissolved organic P (DOP) were determined in waters from pipe-drains (at 65-cm depth) from the Broadbalk Experiment at Rothamsted Research,UK. Average TP and PP exceeded 1 mg L-1 in about half of the 12 plots receiving superphosphate for the 5 measurements taken between December 2000 and April 2001. Ranging between 33.8% and 87.3% of TP,PP was the largest P fraction in drainage waters,with DOP,ranging from 0.5% to 26.2% of TP,being the smallest fraction. Mean proportions of PP,MRP and DOP in TP in drainage waters were 63.4%,32.5% and 4.1%,respectively. These findings support previous findings that P losses from soil to drainage waters were much larger than previously thought,and could therefore make a significant contribution to eutrophication.

  9. First high-voltage measurements using Ca{sup +} ions at the ALIVE experiment

    Energy Technology Data Exchange (ETDEWEB)

    König, K., E-mail: kkoenig@ikp.tu-darmstadt.de [Technische Universität Darmstadt, Institut für Kernphysik (Germany); Geppert, Ch. [Universität Mainz, Institut für Kernchemie (Germany); Krämer, J.; Maaß, B. [Technische Universität Darmstadt, Institut für Kernphysik (Germany); Otten, E. W. [Universität Mainz, Institut für Physik (Germany); Ratajczyk, T.; Nörtershäuser, W. [Technische Universität Darmstadt, Institut für Kernphysik (Germany)

    2017-11-15

    Many physics experiments depend on accurate high-voltage measurements to determine for example the exact retardation potential of an electron spectrometer as in the KATRIN experiment or the acceleration voltage of the ions at ISOL facilities. Until now only precision high-voltage dividers can be used to measure voltages up to 65 kV with an accuracy of 1 ppm. However, these dividers need frequent calibration and cross-checking and the direct traceability is not given. In this article we will describe the status of an experiment which aims to measure high voltages using collinear laser spectroscopy and which has the potential to provide a high-voltage standard and hence, a calibration source for precision high-voltage dividers on the 1 ppm level.

  10. Research and Experiments on a Unipolar Capacitive Voltage Sensor

    Directory of Open Access Journals (Sweden)

    Qiang Zhou

    2015-08-01

    Full Text Available Voltage sensors are an important part of the electric system. In service, traditional voltage sensors need to directly contact a high-voltage charged body. Sensors involve a large volume, complex insulation structures, and high design costs. Typically an iron core structure is adopted. As a result, ferromagnetic resonance can occur easily during practical application. Moreover, owing to the multilevel capacitor divider, the sensor cannot reflect the changes of measured voltage in time. Based on the electric field coupling principle, this paper designs a new voltage sensor; the unipolar structure design solves many problems of traditional voltage sensors like the great insulation design difficulty and high costs caused by grounding electrodes. A differential signal input structure is adopted for the detection circuit, which effectively restrains the influence of the common-mode interference signal. Through sensor modeling, simulation and calculations, the structural design of the sensor electrode was optimized, miniaturization of the sensor was realized, the voltage division ratio of the sensor was enhanced, and the phase difference of sensor measurement was weakened. The voltage sensor is applied to a single-phase voltage class line of 10 kV for testing. According to the test results, the designed sensor is able to meet the requirements of accurate and real-time measurement for voltage of the charged conductor as well as to provide a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system. Therefore, it can satisfy the development demands of the smart power grid.

  11. Percutaneous drainage in the treatment of emphysematous pyelonephritis: 10-year experience

    Energy Technology Data Exchange (ETDEWEB)

    Chen, M.; Huang, C.; Chou, Y.; Huang, Ch.; Chiang, C.; Liu, G. [Chung-Ho Memorial Hospital, Kaohsiung Medical College, Taiwan (China)

    1997-11-01

    CT is an efficient imaging method for diagnosis, guiding the drainage procedures and monitoring response to percutaneous drainage of emphysematous pyelonephritis. Antibiotic therapy combined with CT guided percutaneous drainage of emphysematous pyelonephritis is an acceptable alternative to antibiotic therapy with surgical intervention. (authors)

  12. A 1-D modelling of streaming potential dependence on water content during drainage experiment in sand

    CERN Document Server

    Allègre, Vincent; Ackerer, Philippe; Jouniaux, Laurence; Sailhac, Pascal; 10.1111/j.1365-246X.2012.05371.x

    2012-01-01

    The understanding of electrokinetics for unsaturated conditions is crucial for numerous of geophysical data interpretation. Nevertheless, the behaviour of the streaming potential coefficient C as a function of the water saturation Sw is still discussed. We propose here to model both the Richards' equation for hydrodynamics and the Poisson's equation for electrical potential for unsaturated conditions using 1-D finite element method. The equations are first presented and the numerical scheme is then detailed for the Poisson's equation. Then, computed streaming potentials (SPs) are compared to recently published SP measurements carried out during drainage experiment in a sand column. We show that the apparent measurement of DV / DP for the dipoles can provide the SP coefficient in these conditions. Two tests have been performed using existing models for the SP coefficient and a third one using a new relation. The results show that existing models of unsaturated SP coefficients C(Sw) provide poor results in term...

  13. Summary of transient high-voltage calculations for the FRX-C experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kewish, R.W. Jr.; Rej, D.J.

    1982-06-01

    Calculations of the electrical circuit equations are performed over a wide range of parameters corresponding to the FRX-C field-reversed THETA-pinch experiment at Los Alamos. Without any plasma or external damping, serious voltage doubling and quadrupling of the main capacitor bank charge voltage are observed. These oscillating high voltages are found to be adequately suppressed by the strategic placement of external snubber circuitry. On the other hand, no doubling of the THETA-pinch preionization bank charge voltage is found. Calculations of the equations for the z-pinch preionization circuit are also performed.

  14. An initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery.

    Science.gov (United States)

    Costa, Altair da Silva; Bachichi, Thiago; Holanda, Caio; Rizzo, Luiz Augusto Lucas Martins De

    2016-01-01

    To report an initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery. This was a prospective observational study involving consecutive patients, ≤ 14 years of age, treated at a pediatric thoracic surgery outpatient clinic, for whom pulmonary resection (lobectomy or segmentectomy via muscle-sparing thoracotomy) was indicated. The parameters evaluated were air leak (as quantified with the digital system), biosafety, duration of drainage, length of hospital stay, and complications. The digital system was used in 11 children (mean age, 5.9 ± 3.3 years). The mean length of hospital stay was 4.9 ± 2.6 days, the mean duration of drainage was 2.5 ± 0.7 days, and the mean drainage volume was 270.4 ± 166.7 mL. The mean maximum air leak flow was 92.78 ± 95.83 mL/min (range, 18-338 mL/min). Two patients developed postoperative complications (atelectasis and pneumonia, respectively). The use of this digital system facilitated the decision-making process during the postoperative period, reducing the risk of errors in the interpretation and management of air leaks. Relatar a experiência inicial com um sistema de drenagem digital no pós-operatório de cirurgia torácica pediátrica. Estudo observacional e prospectivo envolvendo pacientes consecutivos do ambulatório de cirurgia torácica pediátrica da instituição, com idade até 14 anos, e com indicação de ressecção pulmonar (lobectomia e/ou segmentectomia através de toracotomia poupadora muscular). Os parâmetros avaliados foram perda aérea (quantificada com o sistema digital), biossegurança, tempo de drenagem, tempo de internação e complicações. O sistema digital foi utilizado em 11 crianças, com média de idade de 5,9 ± 3,3 anos. A média do tempo de internação foi de 4,9 ± 2,6 dias, a de tempo de drenagem foi de 2,5 ± 0,7 dias, e a de volume de drenagem foi de 270,4 ± 166,7 ml. A média da perda aérea máxima foi de 92,78 ± 95,83 ml

  15. Sorption and distribution of aged atrazine residues in the drainage system of an outdoor lysimeter experiment

    Science.gov (United States)

    Jablonowski, N. D.; Schäffer, A.; Burauel, P.

    2009-04-01

    Even though the environmental impact of the herbicide atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] is a matter of controversy, it is still extensively applied for agricultural purposes. Particularly in the US, atrazine has been applied to approximately 70% of all corn acreages in the last 18 years. Atrazine is banned in the EU but its use is increasing in countries like China, Brazil and India. Therefore, the worldwide soil burden of this compound must be enormous. Atrazine has been found to be highly persistent in the environment and it has been suggested that it is moderately mobile in the soil profile. As a result, it is found in most groundwater aquifers and surface waters in agricultural areas in the US. Even in Germany, where it was prohibited in 1991, it is still found in groundwater wells below agriculturally used land where it was formerly applied. For a long-term outdoor lysimeter experiment with a disturbed soil column, a drainage system of fine gravel was originally embedded at the bottom of the lysimeter. In this drainage system, atrazine and its metabolite 2-hydroxy-atrazine were extracted as long as 22 years after the last atrazine application. Due to the radiolabelling, the spatial distribution of the atrazine residues can be evaluated in fractions like fine clay particles attached to the gravel or in the gravel itself. Approximately 2% of the total gravel consisted of carbonaceous, slag-like particles which might retain most of the atrazine and its residues. The latest data will be presented at the session.

  16. Simulating drainage and imbibition experiments in a high-porosity micromodel using an unstructured pore network model

    NARCIS (Netherlands)

    Joekar Niasar, V.; Hassanizadeh, S.M.; Pyrak-Nolte, L.J.; Berentsen, C.W.J.

    2009-01-01

    Development of pore network models based on detailed topological data of the pore space is essential for predicting multiphase flow in porous media. In this work, an unstructured pore network model has been developed to simulate a set of drainage and imbibition laboratory experiments performed on a

  17. Simulating drainage and imbibition experiments in a high-porosity micromodel using an unstructured pore network model

    NARCIS (Netherlands)

    Joekar Niasar, V.; Hassanizadeh, S.M.; Pyrak-Nolte, L.J.; Berentsen, C.W.J.

    2009-01-01

    Development of pore network models based on detailed topological data of the pore space is essential for predicting multiphase flow in porous media. In this work, an unstructured pore network model has been developed to simulate a set of drainage and imbibition laboratory experiments performed on a

  18. Laparoscopy may have a role in the drainage of liver abscess: Early experience at Owerri, Nigeria

    Directory of Open Access Journals (Sweden)

    Christopher N Ekwunife

    2015-01-01

    Full Text Available Background: Image-guided percutaneous drainage with antimicrobial agents is the standard modality of treatment of liver abscess. Open surgical drainage, and lately laparoscopic drainage becomes useful in selected patients. Nigeria is awakening late to the laparoscopic surgery revolution. Public health institutions have started making enormous investments in minimal access surgery, which can augment deficient diagnostic capacities. Objective: To describe the outcomes of the patients who underwent laparoscopic liver abscess drainage at the Federal Medical Centre, Owerri. Materials and Methods: A retrospective analysis of the laparoscopic liver abscess drainage procedures done between the period September 2007 and December 2012 was done. Results: A total of eight patients in the study period were worked up for abscess surgical drainage based on ultrasound (seven cases and computed tomography (one case supported localized collection in the liver. Intraoperatively, one patient was noticed to have nodules on the liver that was later confirmed as hepatocellular carcinoma. Operating time ranged from 37 to 126 min. There was no conversion to open surgery. On the follow-up, one patient had residual abscess of 45 mm diameter size, after 6 weeks, and in whose aspirate acid-fast bacilli were identified. Conclusion: Laparoscopic drainage should be considered in the management of liver abscess.

  19. Intermittent burst dynamics in porous media: experiments on slow drainage flows

    Science.gov (United States)

    Moura, Marcel; Jørgen Måløy, Knut; Toussaint, Renaud

    2017-04-01

    The intermittent burst dynamics during the slow drainage of an artificial quasi-2D porous medium is studied experimentally. We have verified a theoretically predicted scaling for the burst size distribution which was previously accessible only via numerical simulations. We show that this system satisfies a set of conditions known to be true for critical systems, such as intermittent activity with bursts extending over several time and length scales, self-similar macroscopic fractal structure and a scaling behavior for the power spectrum associated with pressure fluctuations during the flow. The observation of a 1/f scaling region in the power spectra is new for porous media flows and, for specific boundary conditions, we notice the occurrence of a transition from 1/f to 1/f2 scaling. An analytically integrable mathematical framework was employed to explain this behavior. References: [1] M. Moura, K. J. Måløy and R. Toussaint, Critical behavior in porous media flow, arXiv preprint (2016). [2] M. Moura, E.-A. Fiorentino, K. J. Måløy, G. Schäfer and R. Toussaint, Impact of sample geometry on the measurement of pressure-saturation curves: Experiments and simulations, Water Resour. Res., 51, 8900 (2015). [3] M. Cieplak and M. O. Robbins, Influence of contact angle on quasistatic fluid invasion of porous media, Phys. Rev. B, 41, 11508 (1990). [4] M. Moura, Burst dynamics in quasi-2D disordered systems: experiments on porous media two-phase flows, PhD thesis, University of Oslo (2016).

  20. Drainage of the air-water-quartz film: experiments and theory.

    Science.gov (United States)

    Manica, Rogerio; Chan, Derek Y C

    2011-01-28

    Experimental results of the kinetics of drainage of the trapped water film between an approaching air bubble and a quartz plate have been analysed using recent theoretical advances in formulating and solving the flow problem in deformable films. Excellent agreement is obtained between experimental data and a model that assumes the bubble-water interface is tangentially immobile in its hydrodynamic response. The coupling between hydrodynamic pressure, disjoining pressure and film deformation is critical in determining the dynamic behaviour of the drainage process. The Reynolds parallel film model that omits the effects of film deformation predicts results that are qualitatively incorrect.

  1. Past, present, and future design of urban drainage systems with focus on Danish experiences

    DEFF Research Database (Denmark)

    Arnbjerg-Nielsen, Karsten

    2011-01-01

    Climate change will influence the water cycle substantially, and extreme precipitation will become more frequent in many regions in the years to come. How should this fact be incorporated into design of urban drainage systems, if at all? And how important is climate change compared to other changes...

  2. Harmonic Analysis of Currents and Voltages Obtained in the Result of Computational Experiment

    Directory of Open Access Journals (Sweden)

    I. V. Novash

    2011-01-01

    Full Text Available The paper considers a methodology for execution of a harmonic analysis of current and voltage numerical values obtained in the result of a computational experiment and saved in an external data file. The harmonic analysis has been carried out in the Mathcad mathematical packet environment.

  3. Organic carbon amendments for passive in situ treatment of mine drainage: Field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, Matthew B.J., E-mail: mbjlindsay@uwaterloo.ca [Department of Earth and Environmental Sciences, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada); Blowes, David W.; Condon, Peter D.; Ptacek, Carol J. [Department of Earth and Environmental Sciences, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada)

    2011-07-15

    Highlights: > Organic carbon amendments can support passive treatment of mine drainage. > Decreased transport of sulfide-oxidation products under sulfate-reducing conditions. > Treatment effectiveness dependent on organic carbon source and amendment rate. - Abstract: A field-scale experiment was conducted to evaluate various organic C sources as amendments for passive treatment of tailings pore water. Varied mixtures of peat, spent-brewing grain (SBG) and municipal biosolids (MB) were assessed for the potential to promote dissimilatory sulfate reduction (DSR) and metal-sulfide precipitation. Five amended cells and one control were constructed in the vadose zone of a sulfide- and carbonate-rich tailings deposit, and the geochemistry, microbiology and mineralogy were monitored for 4 a. Increases in pore-water concentrations of dissolved organic C (DOC) and decreases in aqueous SO{sub 4} concentrations of >2500 mg L{sup -1} were observed in cells amended with peat + SBG and peat + SBG + MB. Removal of SO{sub 4} was accompanied by shifts in {delta}{sup 34}S-SO{sub 4} values of >+30 per mille, undersaturation of pore water with respect to gypsum [CaSO{sub 4}.2H{sub 2}O], and increased populations of SO{sub 4}-reducing bacteria (SRB). Decreases in aqueous concentrations of Zn, Mn, Ni, Sb and Tl were observed for these cells relative to the control. Organic C introduction also supported growth of Fe-reducing bacteria (IRB) and increases in Fe and As concentrations. Enhanced Fe and As mobility occurred in all cells; however, maximum concentrations were observed in cells amended with MB. Subsequent decreases in Fe and As concentrations were attributed to DSR and metal-sulfide precipitation. The common presence of secondary Zn-S and Fe-S phases was observed by field emission-scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDS) spectroscopy. Selective extractions indicated that large decreases in water-soluble SO{sub 4} occurred in cells that supported DSR

  4. Predicting infiltration and pollutant retention in sustainable drainage systems: Experiments, modelling and design

    OpenAIRE

    Quinn, Ruth; Dussaillant, Alejandro

    2014-01-01

    A major problem of increasing urbanization is the rise in pollution caused by runoff, affecting water quality directly and due to combined sewer overflows. Among alternative strategies, Sustainable Drainage Systems (SuDS) such as rain gardens and other bioretention facilities is becoming more widespread. Previous research has focused primarily on hydrologic design, including the degree to which groundwater is replenished by these systems, and models have been developed to quantify the extent ...

  5. Data from a solute transport experiment in the Leviathan Mine drainage, Alpine County, California, October 1982

    Science.gov (United States)

    Flint, M.R.; Bencala, K.E.; Zellweger, G.W.; Hammermeister, D.P.

    1985-01-01

    A twenty-four hour injection of chloride and sodium was made into Leviathan Creek, Alpine County, California to aid interpretation of the coupled interactions between physical transport processes and geochemical reactions. Leviathan Creek was chosen because it receives acid mine drainage from Leviathan Mine, an abandoned open-pit sulfur mine. Water samples were collected at 15 sites along a 4.39 kilometer reach and analyzed for chloride, sodium, sulfate and fluoride. Dissolved concentrations are presented in tabular format and time-series plots. Duplicate samples were analyzed by two laboratories: the Central Laboratory, Denver, Colorado and a research laboratory in Menlo Park, California. A tabular comparison of the analyses and plots of the differences between the two laboratories is presented. Hydrographs and instantaneous discharge measurements are included. (USGS)

  6. Voltage and reactive power control in WPPs. Solutions adopted and lessons learned from three international experiences

    Energy Technology Data Exchange (ETDEWEB)

    Quinonez-Varela, G.; Lorenzo-Sotelo, P.; Alonso-Sadaba, O.; Arlaban-Gabeiras, M.T.; Solano-Lopez, L.; Giraut-Ruso, E.; Chocarro-Aguirrebengoa, I.; Duddy, P.; Ruiz-Guillen, J.; Rebollo-Rico, I. [Acciona Energia, S.A., Sarriguren (Spain)

    2010-07-01

    Voltage and reactive power control is a requirement imposed on wind power plants by numerous System Operators around the world in recent years. Nowadays, more stringent demands are being enforced to allow a larger and safer grid integration of wind generation. The Grid Codes defining these requirements differ from each other depending on the country, characteristics of the grid and other site specific conditions. This paper presents three relevant examples of Acciona's experience in adopting solutions to meet the latest voltage and reactive control requirements in Canada, Australia and Spain, each case based on different wind turbine technology namely Full Converter, DFIG and Squirrel Cage respectively. A thorough discussion of the solutions is provided including a description of the control algorithms and results from field tests performed to demonstrate compliance. (orig.)

  7. The voltage limitation for phase coherence experiments: non-equilibrium effects versus Joule heating

    Science.gov (United States)

    Linke, H.; Omling, P.; Xu, Hongqi; Lindelof, P. E.

    1996-12-01

    The breaking of phase coherence of electrons by a finite bias voltage is studied in a quasi-one-dimensional electron gas. Although the wire is longer than the energy relaxation length we find that Joule heating in the wire is not important for dephasing of non-equilibrium electrons. Instead, phase breaking occurs by electron-electron interaction due to the excess energy of the injected electrons with respect to the Fermi energy. The relevant limiting parameter for phase coherence is, therefore, the bias voltage, rather than the dissipated power. A model calculation suggests that our results are of general relevance for coherence experiments in one-dimensional geometry on length scales of the same order of magnitude as the energy relaxation length.

  8. Foam consolidation and drainage.

    Science.gov (United States)

    Jun, S; Pelot, D D; Yarin, A L

    2012-03-27

    A theoretical model of foam as a consolidating continuum is proposed. The general model is applied to foam in a gravity settler. It is predicted that liquid drainage from foam in a gravity settler begins with a slow drainage stage. Next, a stage with faster drainage occurs where the drainage rate doubles compared to the initial stage. The experiments conducted within the framework of this work confirmed the theoretical predictions and allowed measurements of foam characteristics. Foams of three different concentrations of Pantene Pro-V Classic Care Solutions shampoo were studied, as well as the addition of polyethylene oxide (PEO) in one case. The shampoo's main foaming components are sodium lauryl sulfate and sodium laureth sulfate. It is shown to what extent foam drainage is slowed down by using higher shampoo concentrations and how it is further decreased by adding polymer (PEO).

  9. Switching between hydrophobic and wettable conditions in soil: experiments to assess the influence of cracks, roots and subsurface drainage impedance

    Science.gov (United States)

    Urbanek, E.; Walsh, R. P. D.; Shakesby, R. A.

    2012-04-01

    Although much is known about soil hydrophobicity, assessments of the overall hydrological and erosional significance of the soil property in areas affected by it are greatly hampered by a lack of knowledge on switching between hydrophobic and hydrophilic states. This arises mainly because of (1) the destructive nature of methods of assessing hydrophobicity, (2) its often high local spatial variability and (3) difficulties of relating hydrophobicity results to meaningful soil moisture values. Also, very little is known about the influence which cracks and holes through hydrophobic soil and the presence or absence of subsurface impeding layers have on the 3D pattern and speed of hydrophobicity change during wetting and drying cycles. These issues form the focus of the present paper, which was carried out as part of the EU DESIRE Project. A laboratory experimental approach was adopted. Three different soils of equal initial hydrophibicity class when dry (18 % MED), but of contrasting texture and total carbon content, were investigated: (1) from the scrub-covered (dominated by Erica umbellata, Calluna vulgaris and Pterospartum tridentatum) Vale Torto catchment in Gois municipality, central Portugal (an area where the impacts of prescribed fire were being assessed); (2) soil around a Chamaecyparis lawsonia tree in South Wales; and (3) a vegetated coastal sand-dune location at Nicholaston, Gower Peninsula, South Wales. For the experiments, 106 samples of sieved (< 2 mm), dried soil were placed to a depth of 10 cm in standardized transparent pots (16.5 cm high, top diameter 16 cm, basal diameter 11 cm). Equal numbers of samples were prepared with either (i) five simulated holes, (ii) two simulated linear cracks (in both cases extending downwards to the sample base) and (iii) control soil samples without cracks or holes). Samples were also either (i) sealed at the base to create subsurface impeded drainage or (ii) provided with unimpeded basal drainage by insertion of

  10. Ultrasound-guided percutaneous drainage of meniscal cysts: preliminary clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    MacMahon, P.J. [Department of Radiology, Cappagh National Orthopaedic Hospital, Finglas, Dublin (Ireland)]. E-mail: petermacmahon@yahoo.com; Brennan, D.D. [Department of Radiology, Cappagh National Orthopaedic Hospital, Finglas, Dublin (Ireland); Duke, D. [Department of Radiology, Cappagh National Orthopaedic Hospital, Finglas, Dublin (Ireland); Forde, S. [Department of Radiology, Cappagh National Orthopaedic Hospital, Finglas, Dublin (Ireland); Eustace, S.J. [Department of Radiology, Cappagh National Orthopaedic Hospital, Finglas, Dublin (Ireland)

    2007-07-15

    Aim: To evaluate the efficacy of ultrasound-guided percutaneous drainage of symptomatic meniscal cysts. Materials and methods: Patients with lateral knee joint tenderness and swelling and confirmed meniscal cyst on magnetic resonance imaging (MRI) were consecutively enrolled for ultrasound-guided percutaneous cyst aspiration. Cysts were injected with local anaesthetic and steroid before completion of procedure. All 18 patients (all male, average age 33 years) were subsequently followed up (average time 10 months) and meniscal cyst symptoms assessed by questionnaire. Fischer's exact test used to analyse the data. Results: In every case the procedure was well tolerated, and each patient indicated that they would be willing to have a repeat procedure in the future. Ten patients reported complete resolution of symptoms secondary to therapeutic cyst aspiration and had resumed participation in high-performance sport. Two patients reported a satisfactory sustained response, reporting only occasional 'twinges of pain'. In the remaining six patients, symptoms returned after an initial pain-free period. The pain-free period ranged from 1-8 weeks. In this study, patient outcome did not significantly correlate with any meniscal cyst characteristic. Conclusion: Ultrasound-guided percutaneous aspiration of meniscal cysts is a well-tolerated, simple, and safe procedure. In this small patient series, it was associated with positive early results with favourable outcomes in the mid to long-term. It should be considered in patients unsuitable for surgical debridement or as an interim therapy if surgery is delayed or postponed.

  11. High-voltage safety fuses for the transition-radiation tracking detector in the ATLAS experiment

    CERN Document Server

    Voronov, S A; Onishchenko, E M; Simakov, A B; Sosnovtsev, V V; Suchkov, S; Sugrobova, T A

    2004-01-01

    A safety fuse has been designed for the electrical protection of gas- filled detectors in the ATLAS experiment at CERN (Geneva, Switzerland). The fuse is a polished lithium niobate plate with a titanium strip of 91-kOmega resistance deposited by the photolithographic technique. The forced blowout time of the fuse is 10-50 ms; whereupon the leakage current through it is less than 1 nA at a 2-kV voltage. The resistance of the fuse case is greater than or equivalent equal' greater than 10**1**2 Omega. Its overall dimensions are 5.8 multiplied by 3.8 multiplied by 2 mm.

  12. Voltage spike observation in superconducting cable-in-conduit conductor under ramped magnetic fields. Pt. 1: Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sangkwon Jeong; Schultz, J.H.; Takayasu, Makoto; Vysotsky, Vitaly; Michael, P.C. [Massachusetts Inst. of Technology, Plasma Fusion Center, Cambridge, MA (United States); Warnes, William [Oregan State Univ., Corvallis, OR (United States); Shen, Stewart [Lawrence Livermore National Lab., Livermore, CA (United States)

    1997-06-01

    A 27-strand hybrid superconducting cable-in-conduit conductor (CICC) was fabricated and tested under quickly-ramped high magnetic fields. When the field increased linearly on the CICC, the voltage signal showed several intermittent spikes before it quenched. This paper describes an observation of peculiar voltage spikes during these ramp-rate limitation experiments. The voltage spikes are interpreted as quench precursors and understood as current redistribution events within the local cable inside the conduit. A quantitative correlation is obtained for the magnetic field at which the first voltage spike occurs during ramping fields. The non-uniform current distribution among the strands and the induced loop current in the cable, which is generated by ramped fields, are found to be responsible for the voltage spikes. (author)

  13. SPEAR-1: An experiment to measure current collection in the ionosphere by high voltage biased conductors

    Science.gov (United States)

    Raitt, W. John; Myers, Neil B.; Roberts, Jon A.; Thompson, D. C.

    1990-01-01

    An experiment is described in which a high electrical potential difference, up to 45 kV, was applied between deployed conducting spheres and a sounding rocket in the ionosphere. Measurements were made of the applied voltage and the resulting currents for each of 24 applications of different high potentials. In addition, diagnostic measurements of optical emissions in the vicinity of the spheres, energetic particle flow to the sounding rocket, dc electric field and wave data were made. The ambient plasma and neutral environments were measured by a Langmuir probe and a cold cathode neutral ionization gauge, respectively. The payload is described and examples of the measured current and voltage characteristics are presented. The characteristics of the measured currents are discussed in terms of the diagnostic measurements and the in-situ measurements of the vehicle environment. In general, it was found that the currents observed were at a level typical of magnetically limited currents from the ionospheric plasma for potentials less than 12 kV, and slightly higher for larger potentials. However, due to the failure to expose the plasma contactor, the vehicle sheath modified the sphere sheaths and made comparisons with the analytic models of Langmuir-Blodgett and Parker-Murphy less meaningful. Examples of localized enhancements of ambient gas density resulting from the operation of the attitude control system thrusters (cold nitrogen) were obtained. Current measurements and optical data indicated localized discharges due to enhanced gas density that reduced the vehicle-ionosphere impedance.

  14. Large-Scale Electrochemical Energy Storage in High Voltage Grids: Overview of the Italian Experience

    Directory of Open Access Journals (Sweden)

    Roberto Benato

    2017-01-01

    Full Text Available This paper offers a wide overview on the large-scale electrochemical energy projects installed in the high voltage Italian grid. Detailed descriptions of energy (charge/discharge times of about 8 h and power intensive (charge/discharge times ranging from 0.5 h to 4 h installations are presented with some insights into the authorization procedures, safety features, and ancillary services. These different charge/discharge times reflect the different operation uses inside the electric grid. Energy intensive storage aims at decoupling generation and utilization since, in the southern part of Italy, there has been a great growth of wind farms: these areas are characterized by a surplus of generation with respect to load absorption and to the net transport capacity of the 150 kV high voltage backbones. Power intensive storage aims at providing ancillary services inside the electric grid as primary and secondary frequency regulation, synthetic rotational inertia, and further functionalities. The return on experience of Italian installations will be able to play a key role also for other countries and other transmission system operators.

  15. The 100 kV Faraday cage (High Voltage Deck) for the SPIDER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boldrin, Marco, E-mail: marco.boldrin@igi.cnr.it [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete S.p.A.), Corso Stati Uniti 4, 35127 Padova (Italy); Grando, Luca; Pesce, Alberto; Recchia, Mauro; Toigo, Vanni [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete S.p.A.), Corso Stati Uniti 4, 35127 Padova (Italy); Gutierrez, Daniel; Simon, Muriel [Fusion for Energy, c/o Josep Pla 2, 08019 Barcelona (Spain); Faoro, Giovanni; Guion, Andrea; Maggiora, Edoardo; Pedron, Diego [COELME – Costruzioni Elettromeccaniche S.p.A., via G. Galilei no. 1/2, 30036 S. Maria di Sala, Venezia (Italy); Roman, Anita [Studio di Ingegneria RS s.r.l., Viale dell’Arcella 1, 35153 Padova (Italy); Decamps, Hans [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France)

    2015-10-15

    Highlights: • A 100 keV experiment is under construction to optimize ITER NBI Ion Source. • The Ion Source Power Supplies are hosted inside a wide −100 kVdc Faraday cage (HVD). • The paper reports on the design solutions of the HVD. • Electrostatic and electromagnetic analyses are presented. • Procurement activities status is reported. - Abstract: In order to optimize the design and operation of the Ion Source for the ITER Neutral Beam Injector (NBI), a dedicated 100 keV Ion Source, identified as Source for the Production of Ions of Deuterium Extracted from RF plasma (SPIDER), is under construction in the Neutral Beam Test Facility, at the Consorzio RFX premises, in Padua, Italy. The Ion Source, polarized at −112 kVdc voltage, will produce negative ions (Deuterium D{sup −} or Hydrogen H{sup −}) which, extracted from the Plasma Grid with an extraction voltage up to 12 keV, are accelerated up to 100 keV by the 100 kVdc Power Supply (100 kV PS). The required Ion Source and the Extraction Power Supplies (ISEPS) system and the associated diagnostics are hosted inside a High Voltage Deck (HVD), a −100 kVdc air-insulated Faraday cage. These power supplies and various diagnostics and control equipment are connected to the Ion Source by means of a High Voltage Transmission Line (TL). The HVD (procurement started mid 2013; delivery on site in the second half of 2014) will consist of a wide structure (13 m (L) × 11 m (W) × 5 m (H)), designed to support the weight of the ISEPS components, mounted on supporting insulators and clad with a conductive metal sheet in order to reduce the electromagnetic interference (EMI). The paper reports on the design solutions of the HVD focusing on insulation, mechanical, thermal and EMI issues. The details of the main HVD interfaces with the TL and with insulating transformer are also described. Finite Element (FE) analyses have been performed, on the one hand, to verify the configuration from the electrostatic point of

  16. Optimization Study on the Space and Depth of Subsurface Drainage Tubes for Greenhouse Salty Soils: A 3-Year Field Experiment in South of China

    Directory of Open Access Journals (Sweden)

    Yaming Zhai

    2015-04-01

    Full Text Available A well-designed subsurface drainage system with reasonable drain space and depth contributes to large ratio of desalination and high crop yield. In order to find out the optimal space and depth of subsurface drainage tubes for tomato cultivation in greenhouse salty soils in south of China, drainage treatments with different buried methods were designed, the tomato quality, yield, Irrigation Water Use Efficiency (IWUE and surface soil electricity conductivity in the treatments were observed during 2010 to 2012 growth seasons and the principle component analysis model and projection pursuit model were used to select the treatment with best comprehensive effects. Results showed that: (1 The tomato yield was increased by 14.21 to 50.29% during the growth seasons; (2 Surface soil EC decreased significantly, although in the process of experiments, surface soil EC of some treatments showed a temporary rise; (3 Under the same buried depth, the closer arrangement of subsurface drainage tubes appeared to be more effective for the yield gaining and topsoil desalination; (4 T7 was proved to be the optimal treatment according to the calculations of projection pursuit model, the comprehensive effects of which were the best, mainly embodying in improving the tomato quality, increasing the yield and IWUE and reducing salinity in topsoil. In this study, 0.8m depth combining with 4m space was selected as the optimized layout of subsurface drainage tubes for the tomato cultivation in greenhouse salty soils of south China.

  17. Field experiments of Controlled Drainage of agricultural clay soils show positive effects on water quantity (retention, runoff) and water quality (nitrate leaching).

    Science.gov (United States)

    schipper, peter; stuyt, lodewijk; straat, van der, andre; schans, van der, martin

    2014-05-01

    Despite best management practices, agriculture is still facing major challenges to reduce nutrients leaching to the aquatic environment. In deltas, most of total nutrient losses from artificially drained agricultural soils are discharged via drains. Controlled drainage is a promising measure to prevent drainage of valuable nutrients, improve water quality and agricultural yield and adapt to climate change (reduce peak runoff, manage water scarcity and drought). In The Netherlands, this technique has attracted much attention by water managers and farmers alike, yet field studies to determine the expected (positive) effects for Dutch conditions were scarce. Recently, a field experiment was set up on clay soils. Research questions were: how does controlled, subsurface drainage perform on clay soils? Will deeper tile drains function just as well? What are the effects on drain water quality (especially with respect to nitrogen and salt) and crop yield? An agricultural field on clay soils was used to test different tile drainage configurations. Four types of tile drainage systems were installed, all in duplicate: eight plots in total. Each plot has its own outlet to a control box, where equipment was installed to control drain discharge and to measure the flow, concentrations of macro-ions, pH, nitrogen, N-isotopes and heavy metals. In each plot, groundwater observation wells and suction cups are installed in the saturated and vadose zones, at different depths, and crop yield is determined. Four plots discharge into a hydrologic isolated ditch, enabling the determination of water- and nutrient balances. Automatic drain water samplers and innovative nitrate sensors were installed in four plots. These enable identification and unravelling so-called first flush effects (changes in concentrations after a storm event). Water-, chloride- and nitrogen balances have been set up, and the interaction between groundwater and surface water has been quantified. The hydrological

  18. Experimental modeling of high-voltage corona discharge using design of experiments

    Institute of Scientific and Technical Information of China (English)

    Rezzouga M; Tilmatine A; Gouri R; Medics K; Dascalescu L

    2007-01-01

    Many studies,both experimental and numerical,were devoted to the electric current of corona discharge and some mathematical models were proposed to express it.As it depends on several parameters,it is difficult to find a theoretical or an experimental formula,which considers all the factors.So we opted for the methodology of experimental designs,also called Tagushi's methodology,which represents a powerful tool generally employed when the process has many factors to consider.The objective of this paper is to model current using this experimental methodology.The factors considered were geometrical factors (interelectrode interval,surface of the grounded plane electrode,curvature radius of the point electrode),climatic factors (temperature and relative humidity),and applied high voltage.Results of experiments made it possible to obtain mathematical models and to analyse the interactions between all factors.

  19. MR-guided percutaneous drainage of abdominal fluid collections in combination with X-ray fluoroscopy: initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Buecker, A.; Neuerburg, J.M.; Adam, G.B.; Nolte-Ernsting, C.C.A.; Glowinski, A.; Guenther, R.W. [Clinic for Diagnostic Radiology, Univ. of Technology Aachen (Germany); Hunter, D.W. [Dept. of Radiology, University of Minnesota, Minneapolis, MN (United States); Vaals, J.J. van [Philips Medical Systems, Best (Netherlands)

    2001-04-01

    The aim of this study was to examine the feasibility of a hybrid interventional MR system, which combines a closed bore magnet with a C-arm fluoroscopy unit for percutaneous drainage of abdominal fluid collections. During the past 2 years, we have performed four drainage procedures in four patients (mean age 47 years). Three patients had abscesses (psoas muscle, kidney, subphrenic location) and the fourth patient had a recurrent splenic cyst. All procedures were performed on an interventional MR system consisting of a 1.5-T ACS-NT scanner combined with a specially shielded C-arm. The drainages were guided by T1-weighted fast gradient-echo images, T2-weighted single-shot turbo spin-echo images or both. A standard 18 G (1.2 mm) nonferromagnetic stainless steel needle with a Teflon sheath was used for the punctures following which a 0.89 mm nitinol guidewire was inserted into the fluid collection. Thereafter, the patient was positioned in the immediate adjacent fluoroscopy unit and a drainage catheter was placed under fluoroscopic control. All drainage catheters were successfully placed into the fluid collections, as proven by fluid aspiration and resolution of the collection. The mean time needed for the entire drainage procedure (MR and fluoroscopy) was 110 min. No procedure-related complications occurred. It is feasible to perform drainage procedures on a closed-bore MR scanner. The multiplanar imaging capabilities of MR are particularly helpful for fluid collections in the subphrenic location. (orig.)

  20. Area-dependent impedance-based voltage shifts during tribocorrosion of Ti-6Al-4V biomaterials: theory and experiment

    Science.gov (United States)

    Gilbert, Jeremy L.; Mali, Sachin A.; Liu, Yangping

    2016-09-01

    Tribocorrosion of medical devices causes the electrode potential across the device-solution interface to become more negative. This study provides a theoretical impedance-based understanding of voltage versus time changes that arise. It combines tribocorrosion with the voltage-dependent impedance characteristics of the surface, the relative anodic and cathodic areas and the mechanics and electrochemistry of oxide abrasion. An area-dependent Randle’s circuit is used with the tribocorrosion current equation to show the time-dependent voltage change with disruption and repassivation of the oxide. Heredity integrals are used to predict voltage over time for any arbitrary current-time path. Experiments using titanium pin-on-disk fretting corrosion are used to assess the theoretical model and to demonstrate its behavior.

  1. Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line.

    Science.gov (United States)

    Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

    2015-12-30

    A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

  2. Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line

    Directory of Open Access Journals (Sweden)

    Qiang Zhou

    2015-12-01

    Full Text Available A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

  3. Vertical drainage capacity of new electrical drainage board on improvement of super soft clayey ground

    Institute of Scientific and Technical Information of China (English)

    沈扬; 励彦德; 黄文君; 徐海东; 胡品飞

    2015-01-01

    As an advanced polymer composites electro-kinetic geosynthetics, the electro-osmotic vertical drainage (EVD) board could drain water quickly and accelerate consolidation process. However, the drainage rate was mainly impacted by the vertical drainage capability. Therefore, vertical drainage capability at the top of EVD board was theoretically analyzed. Basic requirements for drainage at the top of the board were summed up, as well as the formula of anode pore pressure when losing the vertical drainage capability. Meanwhile, a contrast test on the top and bottom drainage capacities was conducted. In use of the advanced EVD board, the voltage potential and pore pressure of anode were measured. Moreover, the derived formulas were verified. The result shows that the decrease of electric force gradient had an observable impact on the drainage capability. There was nearly no difference between the energy consumption for the two drainage methods. Although a little less water was discharged, the top drainage method had more advantages, such as high initial drainage velocity, few soil cracks, low anode water content and high soil strength. All of these show that the super soft soil ground could be consolidated quickly in use of the advanced EVD board through the top drainage. The top drainage method could efficiently improve the drainage effect, decrease the energy consumption and speed up the project proceeding.

  4. Robust optimization of the output voltage of nanogenerators by statistical design of experiments

    KAUST Repository

    Song, Jinhui

    2010-09-01

    Nanogenerators were first demonstrated by deflecting aligned ZnO nanowires using a conductive atomic force microscopy (AFM) tip. The output of a nanogenerator is affected by three parameters: tip normal force, tip scanning speed, and tip abrasion. In this work, systematic experimental studies have been carried out to examine the combined effects of these three parameters on the output, using statistical design of experiments. A statistical model has been built to analyze the data and predict the optimal parameter settings. For an AFM tip of cone angle 70° coated with Pt, and ZnO nanowires with a diameter of 50 nm and lengths of 600 nm to 1 μm, the optimized parameters for the nanogenerator were found to be a normal force of 137 nN and scanning speed of 40 μm/s, rather than the conventional settings of 120 nN for the normal force and 30 μm/s for the scanning speed. A nanogenerator with the optimized settings has three times the average output voltage of one with the conventional settings. © 2010 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

  5. Unlikely Combination of Experiments With a Novel High-Voltage CIGS Photovoltaic Array: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    del Cueto, J. A.; Sekulic, B. R.

    2006-05-01

    A new high-voltage array comprising bipolar strings of copper indium gallium diselenide (CIGS) photovoltaic (PV) modules was inaugurated in 2005. It is equipped with a unique combination of tests, which likely have never before been deployed simultaneously within a single array: full current-voltage (I-V) traces, high-voltage leakage current measurements, and peak-power tracking or temporal stepped-bias profiling. The array nominally produces 1 kW power at 1 sun. The array's electrical characteristics are continuously monitored and controlled with a programmable electronic load interfaced to a data acquisition system (DAS), that also records solar and meteorological data. The modules are mounted with their frames electrically isolated from earth ground, in order to facilitate measurement of the leakage currents that arise between the high voltage bias developed in the series-connected cells and modules and their mounting frames. Because the DAS can perform stepped biasing of the array as a function of time, synchronous detection of the leakage current data with alternating bias is available. Leakage current data and their dependence on temperature and voltage are investigated. Array power data are analyzed across a wide range of varying illuminations and temperatures from the I-V traces. Array performance is also analyzed from an energy output perspective using peak-power tracking data.

  6. Experience with voltage control from large offshore windfarms: The Danish case

    DEFF Research Database (Denmark)

    Akhmatov, Vladislav

    2009-01-01

    This paper gives an overview of the state of the art and lists future challenges to reactive power and voltage control in the Danish transmission system in relation to large offshore windfarms. Today, the reliable and stable operation of the Danish transmission system is based on the voltage...... and several smaller ones, has shown that the efficient use of windfarms' reactive power and voltage control for the on-land transmission system might be limited by several factors. Among such limiting factors are the reactive power and current capability limits of the electronic power converters...... and switchable capacitor banks of the offshore wind turbines, which are smaller than those of central power plants measured per unit of the active power rating. Combine this with the use of AC cables, tens of kilometres long, to connect the large offshore windfarms to the on-land transmission system...

  7. Utilization of fly ash to improve the quality of the acid mine drainage generated by oxidation of a sulphide-rich mining waste: Column experiments

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Lopez, R.; Nieto, J.M.; de Almodovar, G.R. [University of Huelva, Huelva (Spain). Dept. of Geology

    2007-04-15

    The production of Acid Mine Drainage (AMD) as a result of the oxidative dissolution of sulphides is one of the main pollution problems affecting natural watercourses in mining environments with sulphide-rich residues. In this work, the generation of AMD was prevented by means of the addition of fly ash to sulphide-rich residues in non-saturated column experiments. A column experiment filled with a pyrite-rich sludge with artificial irrigation leached acid drainages (pH approx. 2) containing high concentrations of sulphate, iron and other metals. However, non-saturated column experiments filled with pyritic-rich sludge and fly ash drained leachates characterized by alkaline pH (pH up to 10), low sulphate concentration, and lack of iron and other metals in solution. The pyrite oxidative dissolution at high pH, as a consequence of the leaching of fly ash, favours the metal precipitation inside the column (mainly iron), the coating of pyrite grains, and the attenuation of the oxidation process, resulting in a great improvement in the quality of the leachates.

  8. Experimental Modelling of the Breakdown Voltage of Air Using Design of Experiments

    Directory of Open Access Journals (Sweden)

    REZOUGA, M.

    2009-02-01

    Full Text Available Many experimental and numerical studies were devoted to the electric discharge of air, and some mathematical models were proposed for the critical breakdown voltage. As this latter depends on several parameters, it is difficult to find a formula, theoretical or experimental, which considers many factors. The aim of this paper is to model the critical breakdown voltage in a "Sphere-Sphere� electrodes system by using the methodology of experimental designs. Several factors were considered, such as geometrical factors (inter-electrodes interval, diameter of the electrodes and climatic factors (temperature, humidity. Two factorial centred faces experimental designs (CCF were carried out, a first one for the geometrical factors and a second one for the climatic factors. The obtained results made it possible to propose mathematical models and to study the interactions between the various factors.

  9. High voltage pulse cable and connector experience in the kicker systems at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Harris, K.; Artusy, M.; Donaldson, A.; Mattison, T.

    1991-05-01

    The SLAC 2-mile linear accelerator uses a wide variety of pulse kicker systems that require high voltage cable and connectors to deliver pulses from the drivers to the magnet loads. Many of the drivers in the SLAC kicker systems use cable lengths up to 80 feet and are required to deliver pulses up to 40 kV, with rise and fall time on the order of 20 ns. Significant pulse degradation from the cable and connector assembly cannot be tolerated. Other drivers are required to deliver up to 80 kV, 20 {mu}s pulses over cables 20 feet long. Several combinations of an applicable high voltage cable and matching connector have been used at SLAC to determine the optimum assembly that meets the necessary specifications and is reliable. 14 refs., 3 figs., 1 tab.

  10. Pattern of high voltage electrical injuries in the Kashmir valley: a 10-year single centre experience.

    Science.gov (United States)

    Kasana, R A; Baba, P U F; Wani, A H

    2016-12-31

    The objective was to study the clinical profile of high voltage electrical injuries in Kashmir, and various prevention and safety measures to bring down the incidence of such injuries in the future. All patients (176) with high voltage electrical injuries reporting to our centre from January 2001 to December 2010 were included in the study. The most common age group was 20-40 years, with mean age of 29.77 ± 8.98 years. Incidence was higher among the rural population (68.75%) than in urban areas (31.25%), and in the winter months. Electricians comprised 47.16% of victims. The most common mode of injury was touching a live wire directly or indirectly, and was seen in 63.64% of victims. Average total body surface burned was 15.27 ± 10.15 percent. Right upper limb was most commonly involved (64.20% of patients). Compartment syndrome was seen in 40.34% of patients, and fasciotomies on all the affected limbs saved around half of them. An average of 3.91 surgical procedures per patient were performed. Around one-third of the victims required major amputations. Reconstructive procedures were required in 49.43% of patients. Average hospital stay was 26.81 days. Average mortality rate was 2.27%. High voltage electrical injuries are not uncommon in the Kashmir Valley, and electrical workers are at higher risk. The incidence of high voltage injuries would not be so high if the workers were properly trained, hazards of high-tension lines were explained and the use of safety equipment was made mandatory.

  11. The Baltic Sea Experiment (BALTEX): A European contribution to the investigation of the energy and water cycle over a large drainage basin

    DEFF Research Database (Denmark)

    Raschke, E.; Meywerk, J.; Warrach, K.

    2001-01-01

    The Baltic Sea Experiment (BALTEX) is one of the five continental-scale experiments of the Global Energy and Water Cycle Experiment (GEWEX). More than 50 research groups from 14 European countries are participating in this project to measure and model the energy and water cycle over the large...... drainage basin of the Baltic Sea in northern Europe. BALTEX aims to provide a better understanding of the processes of the climate system and to improve and to validate the water cycle in regional numerical models for weather forecasting and climate studies. A major effort is undertaken to couple...... interactively the atmosphere with the vegetated continental surfaces and the Baltic Sea including its sea ice. The intensive observational and modeling phase BRIDGE, which is a contribution to the Coordinated Enhanced Observing Period of GEWEX, will provide enhanced datasets for the period October 1999-February...

  12. Optical fiber sensor of partial discharges in High Voltage DC experiments

    Science.gov (United States)

    Búa-Núñez, I.; Azcárraga-Ramos, C. G.; Posada-Román, J. E.; Garcia-Souto, J. A.

    2014-05-01

    A setup simulating High Voltage DC (HVDC) transformers barriers was developed to demonstrate the effectiveness of an optical fiber (OF) sensor in detecting partial discharges (PD) under these peculiar conditions. Different PD detection techniques were compared: electrical methods, and acoustic methods. Standard piezoelectric sensors (R15i-AST) and the above mentioned OF sensors were used for acoustic detection. The OF sensor was able to detect PD acoustically with a sensitivity better than the other detection methods. The multichannel instrumentation system was tested in real HVDC conditions with the aim of analyzing the behavior of the insulation (mineral oil/pressboard).

  13. Effects of acid rock drainage on stocked rainbow trout (Oncorhynchus mykiss): an in-situ, caged fish experiment.

    Science.gov (United States)

    Todd, Andrew S; McKnight, Diane M; Jaros, Chris L; Marchitto, Thomas M

    2007-07-01

    In-situ caged rainbow trout (Oncorhynchus mykiss) studies reveal significant fish toxicity and fish stress in a river impacted by headwater acid rock drainage (ARD). Stocked trout survival and aqueous water chemistry were monitored for 10 days at 3 study sites in the Snake River watershed, Colorado, U.S.A. Trout mortality was positively correlated with concentrations of metals calculated to be approaching or exceeding conservative toxicity thresholds (Zn, Mn, Cu, Cd). Significant metal accumulation on the gills of fish stocked at ARD impacted study sites support an association between elevated metals and fish mortality. Observations of feeding behavior and significant differences in fish relative weights between study site and feeding treatment indicate feeding and metals-related fish stress. Together, these results demonstrate the utility of in-situ exposure studies for stream stakeholders in quantifying the relative role of aqueous contaminant exposures in limiting stocked fish survival.

  14. Precision monitoring and calibration of the high-voltage for the KATRIN experiment; Praezisionsueberwachung und Kalibration der Hochspannung fuer das KATRIN-Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Thuemmler, T.

    2007-11-12

    The goal of the KATRIN(KArlsruhe TRIritium Neutrino) Experiment is to directly determine the neutrino rest mass from the kinematics of the tritium-{beta}-decay. KATRIN uses the high resolution and luminosity of a spectrometer following the MAC-E filter principle. Based on the experience of the successful predecessor experiments in Mainz and Troisk and the improved experimental technology, KATRIN aims to reach a sensitivity on the neutrino mass of 0.2 eV/c{sup 2} (90% C.L.). One of the few systematic uncertainties that have to be reduced to meet this goal is the uncertainty of measuring and monitoring the potential of the electrostatic filter of the spectrometer. In tritium measurement mode voltages of about U{sub 0} =-18.6 kV have to be permanently monitored with a maximum uncertainty of 3.3 ppm ({approx} 61mV at U{sub 0}), in order not to add more than {delta}m{sup 2}{sub {nu}{sub ec}}{sup 4} {<=} 0.0075 eV{sup 2} to the total systematic uncertainty. The goal of this work is to build a new precision high voltage divider in cooperation with PTB Braunschweig that reaches an uncertainty of about 1 ppm at voltages up to 35 kV. The divider is based on a new type of precision resistors, which have been screened with respect to their warm up drift and their temperature coefficient at the ppm level. By combining 100 of the best matching samples, the mutual warm up effect could be reduced to a computed value of <0.02 ppm. The precision resistors are mounted in a shielded and temperature stabilized vessel under N{sub 2} gas. The properties of both installed low voltage outputs with the ratios 1972:1 and 3944:1 have been repeatedly calibrated with about one year time difference at the DC high voltage laboratory (division 2.31) of PTB. The performance of the new divider in real measurements has been tested with the prototype of the new condensed {sup 83m}Kr calibration source (CKrS) [Ost08] at the Mainz spectrometer. Detailed stability investigations of the energy of the {sup

  15. High Voltage Solar Concentrator Experiment with Implications for Future Space Missions - S6a-35

    Science.gov (United States)

    George, I. S. Mehdi P. J.; O'Neill, M.; Matson, R.; Borckschmidt, A.

    2004-12-01

    This paper describes the design, development, fabrication, and test of a high performance, high voltage solar concentrator array. This assembly is believed to be the first ever terrestrial triple-junction-cell solar array rated at over 1 kW. The concentrator provides over 200 W/square meter power output at a nominal 600 Vdc while operating under terrestrial sunlight. Space-quality materials and fabrication techniques were used for the array, and the 3005-meter elevation installation below the Tropic of Cancer allowed testing as close as possible to space deployment without an actual launch. The array includes two concentrator modules, each with a 3 square meter aperture area. Each concentrator module uses a linear Fresnel lens to focus sunlight onto a photovoltaic receiver that uses 240 series-connected triple-junction solar cells. Operation of the two receivers in series can provide 1200 Vdc which would be adequate for the "direct drive" of some ion engines or microwave transmitters in space. Lens aperture width is 84 cm and the cell active width is 3.2 cm, corresponding to a geometric concentration ratio of 26X. The evaluation includes the concentrator modules, the solar cells, and the materials and techniques used to attach the solar cells to the receiver heat sink. For terrestrial applications, a finned aluminum extrusion was used for the heat sink for the solar cells, maintaining a low cell temperature so that solar cell efficiency remains high.

  16. Experiments in high voltage electron microscopy. Progress report, October 31, 1976--August 1977

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, T. E.; Hobbs, L. W.; Howitt, D. G.; Barnard, R.; Ro, H.

    1977-07-01

    High voltage electron microscopy (HVEM) is being used to study the effects of irradiation on a variety of materials. The vacancies and interstitials produced by displacement can aggregate to form dislocation loops and voids, annihilate at sinks, or enhance various diffusion processes such as precipitation and recrystallization. Threshold displacement energies, E/sub d/, have been determined for a number of fcc, bcc and hcp metals and for various oxides. In MgO, E/sub d/ is less along (100) than (110); also, E/sub d/ decreases with increasing temperature, possibly due to thermally activated escape of interstitials from recombination volumes or softening of saddle points. The effects of electron irradiation on precipitation in Al--Cu, Al--Si and Ni--Al alloys have been investigated. Precipitation respectively of theta', Si and ..gamma..' is enhanced and growth rates are explicable in terms of theories of radiation-enhanced diffusion, with D/sub rad/ approx. 10/sup -15/ cm/sup 2/ sec/sup -1/. In oxides, damage gives rise to interstitial dislocation loop nucleation and growth in all cases, perfect (110) loops in MgO faulted basal and prismatic loops in Al/sub 2/O/sub 3/. Quantitative analysis of loop growth rates in MgO gives a migration energy of 3.3 eV for anion vacancies. Other radiation effects include sublimation of MgO and decomposition of MgAl/sub 2/O/sub 4/ and Mg/sub 2/SiO/sub 4/ into MgO plus other phases.

  17. Design and Experiments of the High Voltage Pulsed Electric Fields Sterilization System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xihai; FANG Junlong; SHEN Weizheng

    2008-01-01

    This experiment designed the pulsed electric fields (PEF) of high intensity of 100 kV. cml sterilization system. Fluorescent pseudomonas as target cell was operated 180 s in the PEF. By observing the difference of the bacteria before and after the disposal by TEM, it is found that the cell wails of the treated bacteria were broken. Irreversible perforations were formed on the cell membrane. The cell inclusions and cell fragments were leaked. The cell died as a result. The results showed that the PEF sterilization system designed can be used for liquid food sterilization experiments.

  18. High-voltage safety fuses for the transition-radiation tracking detector in the ATLAS experiment

    NARCIS (Netherlands)

    Voronov, SA; Voronov, YA; Onishchenko, EM; Simakov, AB; Sosnovtsev, VV; Suchkov, SI; Sugrobova, TA

    2004-01-01

    A safety fuse has been designed for the electrical protection of gas-filled detectors in the ATLAS experiment at CERN (Geneva, Switzerland). The fuse is a polished lithium niobate plate with a titanium strip of 91-kOmega resistance deposited by the photolithographic technique. The forced blow-out ti

  19. A Tracker for the Mu3e Experiment based on High-Voltage Monolithic Active Pixel Sensors

    CERN Document Server

    Berger, Niklaus; Bachmann, Sebastian; Kiehn, Moritz; Perić, Ivan; Perrevoort, Ann-Kathrin; Philipp, Raphael; Schöning, André; Stumpf, Kevin; Wiedner, Dirk; Windelband, Bernd; Zimmermann, Marco

    2013-01-01

    The Mu3e experiment searches for the lepton flavour violating decay mu+ -> e+e-e+, aiming for a branching fraction sensitivity of 10^-16. This requires an excellent momentum resolution for low energy electrons, high rate capability and a large acceptance. In order to minimize multiple scattering, the amount of material has to be as small as possible. These challenges can be met with a tracker built from high-voltage monolithic active pixel sensors (HV-MAPS), which can be thinned to 50 um and which incorporate the complete read-out electronics on the sensor chip. To further minimise material, the sensors are supported by a mechanical structure built from 25 um thick Kapton foil and cooled with gaseous helium.

  20. A tracker for the Mu3e experiment based on high-voltage monolithic active pixel sensors

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Niklaus, E-mail: nberger@physi.uni-heidelberg.de [Physikalisches Institut, Heidelberg University, Heidelberg (Germany); Augustin, Heiko; Bachmann, Sebastian; Kiehn, Moritz [Physikalisches Institut, Heidelberg University, Heidelberg (Germany); Perić, Ivan [Zentralinstitut für technische Informatik, Heidelberg University, Mannheim (Germany); Perrevoort, Ann-Kathrin; Philipp, Raphael; Schöning, André; Stumpf, Kevin; Wiedner, Dirk; Windelband, Bernd; Zimmermann, Marco [Physikalisches Institut, Heidelberg University, Heidelberg (Germany)

    2013-12-21

    The Mu3e experiment searches for the lepton flavour violating decay μ{sup +}→e{sup +}e{sup −}e{sup +}, aiming for a branching fraction sensitivity of 10{sup −16}. This requires an excellent momentum resolution for low energy electrons, high rate capability and a large acceptance. In order to minimise multiple scattering, the amount of material has to be as small as possible. These challenges can be met with a tracker built from high-voltage monolithic active pixel sensors (HV-MAPS), which can be thinned to 50μm and which incorporate the complete read-out electronics on the sensor chip. To further minimise material, the sensors are supported by a mechanical structure built from 25μm thick Kapton foil and cooled with gaseous helium.

  1. High voltage studies of Xe-129 gas for the TRIUMF nEDM experiment

    Science.gov (United States)

    Katsika, Aikaterini; Canada-Japan UCN Collaboration Collaboration

    2016-09-01

    One of the main sources of systematic uncertainties in neutron electric dipole experiments (nEDM) experiments is related to magnetic field fluctuations. The idea of the atomic co-magnetometer, where polarized atoms are introduced in the same volume with ultra-cold neutrons and measure the precession frequencies of both species, has been used in the past with Hg-199 atoms and led to an improvement of the nEDM upper limit down to 3.010-26 ecm. For the TRIUMF nEDM experiment, we aim to use Xe-129 atoms expecting to suppress this limit ultimately by two orders of magnitude more due to the smaller neutron absorption cross section and the negative (same to that of the neutron) gyromagnetic ratio that Xe-129 possesses. The precession of the Xe-129 atoms will be probed via a two photon exchange process which requires enough Xe-129 atoms such that the pressure in the cell is orders of mTorr. The talk will present the status of the experimental work carried out at TRIUMF which is focused on exploring the dielectric properties of the Xe-129 in the mTorr region as we require a stable electric field of about 12.5 kV/cm in order to improve the current nEDM upper limit.

  2. Endoscopic, transmural drainage and necrosectomy for walled-off pancreatic and peripancreatic necrosis is associated with low mortality--a single-center experience

    DEFF Research Database (Denmark)

    Schmidt, Palle Nordblad; Novovic, Srdan; Roug, Stine

    2015-01-01

    OBJECTIVE: Endoscopic transmural drainage and necrosectomy (ETDN) is a promising alternative to percutaneous drainage and surgical intervention in the treatment of walled-off pancreatic and peripancreatic necroses (WONs). We assessed the outcome and safety profile of ETDN in a single-center patie...... in a single, high-volume center has an acceptable safety profile and is associated with a low mortality....

  3. [Little Dry Creek Drainage

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Map of the drainage boundary, direction of flow, canals and ditches, and streets for the drainage study plan and profile for Little Dry Creek sub area in the North...

  4. Percutaneous Abscess Drainage

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Percutaneous Abscess Drainage An abscess is an infected fluid collection ... are the benefits vs. risks? What is Percutaneous Abscess Drainage? An abscess is an infected fluid collection ...

  5. Transient drainage summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage.

  6. Gas drainage technology of high gas and thick coal seam

    Institute of Scientific and Technical Information of China (English)

    HE Tian-cai; LI Hai-gui; ZHANG Hai-jun

    2009-01-01

    Gas drainage in Jincheng Mining Group Co., Ltd. was introduced briefly and the importance of gas drainage in gas control was analyzed. Combined with coal-bed gas oc-currence and gas emission, the double system of gas drainage was optimized and a pro-gressive gas drainage model was experimented on. For guaranteed drainage, excavation and mining and realization of safety production and reasonable exploitation of gas in coal seams, many drainage methods were adopted to solve the gas problem of the working face.

  7. COMPARATIVE ANALYSIS OF EFFICIENCY OF NANOSTRUCTURED AND POLYURETHANE STENTS FOR DRAINAGE OF THE UPPER URINARY TRACT IN EXPERIMENT

    Directory of Open Access Journals (Sweden)

    S. V. Shkodkin

    2012-01-01

    Full Text Available This article presents the results of a pilot study of experimental stent in comparison to traditionally used. Experi- ments were performed on 20 adult male rabbits weighing 4350–4580 grams. The main study group (10 animals was performed an experimental unilateral implantation of the stent, as a control (10 animals was performed a unilateral stent implantation «White-star standart» (Company Urotech, Germany, of the same diameter. The observation period was 1 month. There were performed laboratory tests of blood and urine, as well as morpholo- gical examination of the kidneys and ureters. We obtain statistically significant benefits of using an experimental stent. 

  8. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric,I et al.

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 1015 neq=cm2 , nearly 100% detection efficiency and a spatial resolution of about 3 μm were demonstrated. Since 2011 the HV detectors have first applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process.

  9. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric, Ivan; Backhaus, Malte; Barbero, Marlon; Benoit, Mathieu; Berger, Niklaus; Bompard, Frederic; Breugnon, Patrick; Clemens, Jean-Claude; Dannheim, Dominik; Dierlamm, Alexander; Feigl, Simon; Fischer, Peter; Fougeron, Denis; Garcia-Sciveres, Maurice; Heim, Timon; Hügging, Fabian; Kiehn, Moritz; Kreidl, Christian; Krüger, Hans; La Rosa, Alessandro; Liu, Jian; Lütticke, Florian; Mariñas, Carlos; Meng, Lingxin; Miucci, Antonio; Münstermann, Daniel; Nguyen, Hong Hanh; Obermann, Theresa; Pangaud, Patrick; Perrevoort, Ann-Kathrin; Rozanov, Alexandre; Schöning, André; Schwenker, Benjamin; Wiedner, Dirk

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 10 15 n eq = cm 2 , nearly 100% detection ef fi ciency and a spatial resolution of about 3 μ m were demonstrated. Since 2011 the HV detectors have fi rst applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process

  10. High voltage engineering

    CERN Document Server

    Rizk, Farouk AM

    2014-01-01

    Inspired by a new revival of worldwide interest in extra-high-voltage (EHV) and ultra-high-voltage (UHV) transmission, High Voltage Engineering merges the latest research with the extensive experience of the best in the field to deliver a comprehensive treatment of electrical insulation systems for the next generation of utility engineers and electric power professionals. The book offers extensive coverage of the physical basis of high-voltage engineering, from insulation stress and strength to lightning attachment and protection and beyond. Presenting information critical to the design, selec

  11. Modeling leakage pathways in subsurface formations. Fluid drainage through multiple fractures in porous media: Insights from Hele Shaw cell experiments

    Science.gov (United States)

    Ray, Sujata

    2017-04-01

    Arresting the recent observed warming of the earth's climate is a challenge requiring the reduction of anthropogenic emissions of carbon dioxide. One option for reducing emissions into the atmosphere is to capture and sequester the released carbon dioxide in geological formations. However, potential geological storage first requires a risk assessment of carbon dioxide escaping to overlying layers and back to the atmosphere through leakage pathways in the formation. This, in turn, requires an understanding of fluid flow through the leakage pathways. In this study, the effect of leakage pathways on the flow of a gravity current was investigated, using an analogue system, a Hele-Shaw cell. Fluid was introduced through the top edge of the cell and flowed out through one or more holes in its impermeable base. The height of the accumulated fluid above the base of the cell at various points along its length and the outflow rate of fluid through the holes was measured. This measurement was conducted with varying conditions of the location, number and strength of source as well as the location and number of holes. At steady state, the fluid motion was in accordance with Darcy's law for horizontal flow in a long thin current. In another set of experiments, in which inflow was stopped and the fluid was allowed to drain out of a single open hole, the outflow rate was in accordance with Darcy's law for one-dimensional flow in the vertical direction until the fluid height above the hole fell below a certain limit. This threshold height was found to be 1.3 cm, which was similar in magnitude to the length of the hole. A time series of photographs tracked the flow of colored dye. The photographs demonstrated that at steady state the fluid traveled for some distance beyond the hole before draining through it. This implies that contaminants may be transported in a formation even beyond an outlet before finally draining out through it. The photographs also documented the shape of the

  12. Design, Experiments and Simulation of Voltage Transformers on the Basis of a Differential Input D-dot Sensor

    Directory of Open Access Journals (Sweden)

    Jingang Wang

    2014-07-01

    Full Text Available Currently available traditional electromagnetic voltage sensors fail to meet the measurement requirements of the smart grid, because of low accuracy in the static and dynamic ranges and the occurrence of ferromagnetic resonance attributed to overvoltage and output short circuit. This work develops a new non-contact high-bandwidth voltage measurement system for power equipment. This system aims at the miniaturization and non-contact measurement of the smart grid. After traditional D-dot voltage probe analysis, an improved method is proposed. For the sensor to work in a self-integrating pattern, the differential input pattern is adopted for circuit design, and grounding is removed. To prove the structure design, circuit component parameters, and insulation characteristics, Ansoft Maxwell software is used for the simulation. Moreover, the new probe was tested on a 10 kV high-voltage test platform for steady-state error and transient behavior. Experimental results ascertain that the root mean square values of measured voltage are precise and that the phase error is small. The D-dot voltage sensor not only meets the requirement of high accuracy but also exhibits satisfactory transient response. This sensor can meet the intelligence, miniaturization, and convenience requirements of the smart grid.

  13. Design, experiments and simulation of voltage transformers on the basis of a differential input D-dot sensor.

    Science.gov (United States)

    Wang, Jingang; Gao, Can; Yang, Jie

    2014-07-17

    Currently available traditional electromagnetic voltage sensors fail to meet the measurement requirements of the smart grid, because of low accuracy in the static and dynamic ranges and the occurrence of ferromagnetic resonance attributed to overvoltage and output short circuit. This work develops a new non-contact high-bandwidth voltage measurement system for power equipment. This system aims at the miniaturization and non-contact measurement of the smart grid. After traditional D-dot voltage probe analysis, an improved method is proposed. For the sensor to work in a self-integrating pattern, the differential input pattern is adopted for circuit design, and grounding is removed. To prove the structure design, circuit component parameters, and insulation characteristics, Ansoft Maxwell software is used for the simulation. Moreover, the new probe was tested on a 10 kV high-voltage test platform for steady-state error and transient behavior. Experimental results ascertain that the root mean square values of measured voltage are precise and that the phase error is small. The D-dot voltage sensor not only meets the requirement of high accuracy but also exhibits satisfactory transient response. This sensor can meet the intelligence, miniaturization, and convenience requirements of the smart grid.

  14. A Study of the Effect of Gold Thickness Distribution in the Jet Plating Process to Optimize Gold Usage and Plating Voltage Using Design of Experiments

    Directory of Open Access Journals (Sweden)

    Aramphongphun Chuckaphun

    2016-01-01

    Full Text Available A gold plating process in the electronics industry can be classified as (i all surface plating or (ii selective plating. Selective plating is more widely used than all surface plating because it can save more gold used in the plating process and takes less plating time. In this research, the selective plating process called jet plating was studied. Factors that possibly affected the gold usage and plating voltage were also studied to reduce the production cost. These factors included (a plating temperature, (b crystal (inhibitor amount, (c distance between workpiece and anode, (d plating current and (e plating speed. A two-level Full Factorial design with center points was first performed to screen the factors. A Central Composite Design (CCD was then employed to optimize the factors in jet plating. The amount of gold usage should be reduced to 0.366 g / 10,000 pieces, the plating speed should be increased to 4 m/min and the plating voltage should not exceed 8.0 V. According to the analysis, the optimal settings should be as follows: the plating temperature at 55.5 deg C, the crystal amount at 90%, the distance at 0.5 mm, the plating current at 2.8 A, and the plating speed at 4.5 m/min. This optimal setting led to gold usage of 0.350 g / 10,000 pieces and a plating voltage of 7.16 V. Confirmation runs of 30 experiments at the optimal conditions were then performed. It was found that the gold usage and the plating voltage of the confirmation runs were not different from the optimized gold usage and plating voltage. The optimal condition was then applied in production, which could reduce the gold usage by 4.5% and increase the plating speed by 12.5% while the plating voltage did not exceed the limit.

  15. Numerical simulation of transient flow in horizontal drainage systems

    Institute of Scientific and Technical Information of China (English)

    Ze-yu MAO; Han XIAO; Ying LIU; Ying-jun HU

    2009-01-01

    A numerical simulation model based on the characteristic-based finite-difference method with a time-line interpolation scheme was developed for predicting transient free surface flow in horizontal drainage systems. The fundamental accuracy of the numerical model was first clarified by comparison with the experimental results for a single drainage pipe. Boundary conditions for junctions and bends, which are often encountered in drainage systems, were studied both experimentally and numerically. The numerical model was applied to an actual drainage system. Comparison with a full-scale model experiment indicates that the model can be used to accurately predict flow characteristics in actual drainage networks.

  16. Monitoring, field experiments, and geochemical modeling of Fe(II) oxidation kinetics in a stream dominated by net-alkaline coal-mine drainage, Pennsylvania, USA

    Science.gov (United States)

    Cravotta, Charles A.

    2015-01-01

    Watershed-scale monitoring, field aeration experiments, and geochemical equilibrium and kinetic modeling were conducted to evaluate interdependent changes in pH, dissolved CO2, O2, and Fe(II) concentrations that typically take place downstream of net-alkaline, circumneutral coal-mine drainage (CMD) outfalls and during aerobic treatment of such CMD. The kinetic modeling approach, using PHREEQC, accurately simulates observed variations in pH, Fe(II) oxidation, alkalinity consumption, and associated dissolved gas concentrations during transport downstream of the CMD outfalls (natural attenuation) and during 6-h batch aeration tests on the CMD using bubble diffusers (enhanced attenuation). The batch aeration experiments demonstrated that aeration promoted CO2 outgassing, thereby increasing pH and the rate of Fe(II) oxidation. The rate of Fe(II) oxidation was accurately estimated by the abiotic homogeneous oxidation rate law −d[Fe(II)]/dt = k1·[O2]·[H+]−2·[Fe(II)] that indicates an increase in pH by 1 unit at pH 5–8 and at constant dissolved O2 (DO) concentration results in a 100-fold increase in the rate of Fe(II) oxidation. Adjusting for sample temperature, a narrow range of values for the apparent homogeneous Fe(II) oxidation rate constant (k1′) of 0.5–1.7 times the reference value of k1 = 3 × 10−12 mol/L/min (for pH 5–8 and 20 °C), reported by Stumm and Morgan (1996), was indicated by the calibrated models for the 5-km stream reach below the CMD outfalls and the aerated CMD. The rates of CO2 outgassing and O2ingassing in the model were estimated with first-order asymptotic functions, whereby the driving force is the gradient of the dissolved gas concentration relative to equilibrium with the ambient atmosphere. Although the progressive increase in DO concentration to saturation could be accurately modeled as a kinetic function for the conditions evaluated, the simulation of DO as an instantaneous equilibrium process did not affect the

  17. Agricultural Drainage Well Intakes

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Locations of surface intakes for registered agriculture drainage wells according to the database maintained by IDALS. Surface intakes were located from their...

  18. Surface Water & Surface Drainage

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data set contains boundaries for all surface water and surface drainage for the state of New Mexico. It is in a vector digital data structure digitized from a...

  19. Airport Pavement Drainage

    Science.gov (United States)

    1990-06-01

    drainage layer and trench drains can be found in Cedergren (10). 4.2 COMPONENTS OF SUBSURFACE DRAINAGE SYSTEM 4.2.1 Outflow Once the water has found...According to Cedergren (10) the open graded aggregate can replace the normally used dense graded materials on an inch-for-inch basis. A main problem in...the perforated pipe to prevent fines from entering, Figure 4.24 (11). Cedergren (10) suggests that collector pipes should be 42 laid with the

  20. High Voltage Test Apparatus for a Neutron EDM Experiment and Lower Limit on the Dielectric Strength of Liquid Helium at Large Volumes

    CERN Document Server

    Long, J C; Boissevain, J G; Clark, D J; Cooper, M D; Gómez, J J; Lamoreaux, S K; Mischke, R E; Penttila, S I

    2006-01-01

    A new search for a permanent electric dipole moment (EDM) of the neutron is underway using ultracold neutrons produced and held in a bath of superfluid helium. Attaining the target sensitivity requires maintaining an electric field of several tens of kilovolts per centimeter across the experimental cell, which is nominally 7.5 cm wide and will contain about 4 liters of superfluid. The electrical properties of liquid helium are expected to be sufficient to meet the design goals, but little is known about these properties for volumes and electrode spacings appropriate to the EDM experiment. Furthermore, direct application of the necessary voltages from an external source to the experimental test cell is impractical. An apparatus to amplify voltages in the liquid helium environment and to test the electrical properties of the liquid for large volumes and electrode spacings has been constructed. The device consists of a large-area parallel plate capacitor immersed in a 200 liter liquid helium dewar. Preliminary r...

  1. Treatment Experience of Laparoscopic Liver Abscess Drainage%腹腔镜肝脓肿引流术治疗体会

    Institute of Scientific and Technical Information of China (English)

    额都; 斯琴高娃

    2014-01-01

    Objective:To investigate the operation indications, operation steps, main operation points and clinical sig-nificance of laparoscopic liver abscess drainage. Methods:The laparoscopic liver abscess drainage surgeries from Jan-uary 2010 to March 2014 were retrospectively analyzed. Results:20 cases of operation were all successful;the patients were cured and discharged from hospital. Conclusion:Laparoscopic liver abscess drainage has the advantages of sim-ple operation, small surgical trauma, quicker recovery of patients, less postoperative complications, less abdominal cav-ity pollution, so it is one of effective methods for the treatment of liver abscess.%目的:探讨腹腔镜肝脓肿引流手术的适应证、手术步骤、手术要点及其临床意义。方法:回顾性分析自2010年1月~2014年3月间进行的腹腔镜肝脓肿引流手术20例。结果:20例手术均获成功,患者治愈出院。结论:腹腔镜肝脓肿引流术操作简单、手术创伤小、术后病人恢复快、并发症少、腹腔污染少,是治疗肝脓肿的有效方法之一。

  2. Experiences of closing in sanitary landfills with geosynthetics clay liners and geocomposites drainage products in Spain and Portugal; Experiencias de sellado de vertederos con geocompuestos impermeabilizantes y drenantes en Espana y Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Abad, P. L.

    2002-07-01

    Since the EC presents the Directive 1999/31 in reference with waste disposal, most of od landfills are closing and new landfills according with this directive are constructing. For this landfill closures, the best experienced solution, not only technically, even financially, is the use of geo synthetics clay liners and geo composites drainage products. Installation facilities are cheaper and the installation times are reduced, even slope stability are improved with this solution. The experience obtained during last years in Spain and Portugal are the purpose of this article. (Author)

  3. 鼻胃管引流在胆总管切开一期缝合术中的护理体会%Nursing Experience in Nasogastric Tube Drainage for Primary Suture of Choledoch Incision

    Institute of Scientific and Technical Information of China (English)

    常永智; 王少彬

    2014-01-01

    目的:探讨鼻胃管引流在胆总管切开一期缝合术中的护理体会。方法:回顾性分析我院2010年5月~2012年5月门诊收住入院的通过内置鼻胆管引流实施腹腔镜或开腹胆总管探查后一期缝合胆总管治疗的70例胆道结石患者的临床资料。结果:70例患者手术均获成功,鼻胃管放置时间为4.6±1.0天;63例(90.0%)患者认为引流效果满意;5例患者引流不畅后应用注射器抽生理盐水冲洗后引流顺利;2例患者发生出血,均为胆管癌患者,应用去甲肾上腺素后症状缓解,均无护理并发症发生。结论:有针对性地提出护理问题并采取相应护理措施,重视并做好基础护理是保证手术成功的前提。%To investigate the nursing experience of nasogastric tube drainage for primary suture of choledoch incision. Methods:Clinical data of 70 biliary calculi outpatient treated with nasogastric tube drainage for primary suture of choledoch incision in our hospital form May 2010 to May 2012 were retrospectively analyzed. Results:70 cases succeeded in operation, placement time of nasogastric tube was 4.6 ± 1.0 days;63 cases (90%) were satisfied with drainage;5 cases of patients with poor drainage were well drainage after the normal saline flushing with syringe;2 patients with cholangiocarcinoma bled, which were remission after applied with norepinephrine, all without nursing complications. Conclusion:The prerequi-site of successful operation is with corresponding nursing measures for pertinency nursing problems and attach importance to basic nursing and achieve.

  4. Currentversus Voltage Curves in Franck-Hertz Experiments%弗兰克-赫兹实验中的伏安特性曲线

    Institute of Scientific and Technical Information of China (English)

    陈小凡

    2015-01-01

    The theoretical relationship between the current and voltage in a Franck-Hertz experiment is given. And the comparisons between the experimental results and theoretical ones are made. The comparisons show that the theoretical results are in agreement with the experimental ones.%给出了弗兰克-赫兹实验中的伏安特性的理论关系,并与实验进行了对比. 对比表明,理论结果与实验结果一致.

  5. Coupling between drainage and coarsening in wet foam

    Indian Academy of Sciences (India)

    S Saha; S Bhaumik; A Roy

    2009-06-01

    Drainage and coarsening are two coupled phenomena during the evolution of wet foam. We show the variation in the growth rate of bubble size, along the height in a column of Gillette shaving foam, by microscope imaging. Simultaneously, the drainage of liquid at the same heights has been investigated by Raman spectroscopic measurements. The observations made in these two sets of experiments indicate the coupling between drainage and coarsening in wet foam. We could explain the correlation between our observed data on drainage and coarsening by the empirical relation, proposed by others, in the literature.

  6. Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

    Science.gov (United States)

    Hauri, James F.; Schaider, Laurel A.

    2009-01-01

    Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

  7. Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

    Science.gov (United States)

    Hauri, James F.; Schaider, Laurel A.

    2009-01-01

    Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

  8. Inorganic contaminants attenuation in acid mine drainage by fly ash and fly ash-ordinary Portland cement (OPC) blends : column experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gitari, W.M. [Venda Univ., Thohoyandou (South Africa). Dept. of Ecology and Resources Management, School of Environmental Studies; Petrik, L.F.; Etchebers, O. [Western Cape Univ., Bellville (South Africa). Environmental and Nanosciences Group, Dept. of Chemistry; Key, D.L. [Western Cape Univ., Bellville (South Africa). Dept. of Chemistry; Okujeni, C. [Western Cape Univ., Bellville (South Africa). Dept. of Earth Sciences

    2010-07-01

    The infiltration of acid mine drainage (AMD) material into mine voids is one of the environmental impacts of underground coal mining. In this study, the mitigation of AMD in a mine void was simulated in laboratory conditions. Various mixtures of fly ash, solid residues, and Portland cement were added to packed columns over a 6-month period. The fly ash additions generated near-neutral to alkaline pH levels, which in turn induced precipitation, co-precipitation, and adsorption contaminant attenuation mechanisms. A modelling study demonstrated that the precipitation of ferrihydrite, Al-hydroxides, Al-oxyhydroxysulphates, gypsum, ettringite, manganite, and rhodochrosite lowered contaminant levels. Results of the study indicated that the pH regime and acidity level of the AMD strongly influenced both the leaching of the toxic trace elements as well as the attenuation of the AMD. 3 refs., 2 figs.

  9. 盐碱地排水沟蓄水后底泥与水体盐分交换试验%Experiment on salt exchange between sediments and ponding water in drainage ditches of saline farmland

    Institute of Scientific and Technical Information of China (English)

    潘延鑫; 罗纨; 贾忠华; 李进; 陈远

    2013-01-01

    temperature was kept at (15±1)℃ during the experiment. The sediment salinity was measured by extracting the pore water through four sampling holes on each column wall. Electrical conductivity of the sediment pore water and the overlying water were measured every 24 hours during the monitoring period. The sediments were taken from a saline agricultural drainage ditches in Lubotan reclamation area in Shaanxi, China, where salinity elevation in the drainage ditches presents a problem to the ecological functions of the ditch system, and freshwater is available for salt flushing in the end of the irrigation season. We measured salinity variations in water and sediments in the experimental columns continuously for a period of 648 hours, then calculated salt fluxes in the water and sediment interface based on measured sediment properties. The monitoring data showed that there existed a linear salinity variation zone (or the diffusion boundary layer) within 10 cm of the sediment and water interface, salinity of water remained stable above 10 cm. The results also showed that salt diffusion within the boundary layer slowed the salt release from the sediment, and the slowing effect increased with the thickness of the boundary layer. Flux calculation results showed that salt fluxes released from the sediment can be predicted with a power function, i.e., salt fluxes decreased rapidly initially and then stabilized with time. Observed salinity change in sediment indicates that salt release through molecular diffusion only in drainage ditches is a slow process, which may have only limited impact on salt balance in drainage ditches when the flushing water moves slowly. And hydrodynamic dispersion is required to speed up release of salt from the ditch sediment in order to remove accumulated salts in the drainage ditches in saline environment.

  10. Wound Drainage Culture (For Parents)

    Science.gov (United States)

    ... to Be Smart About Social Media Wound Drainage Culture KidsHealth > For Parents > Wound Drainage Culture Print A A A What's in this article? ... Have Questions What It Is A wound drainage culture is a test to detect germs such as ...

  11. [Endosonography control of percutaneous paracoccygeal drainage of deep pelvic abscesses after rectum resection].

    Science.gov (United States)

    Truong, S; Willis, S; Jansen, M; Neuerburg, J; Schumpelick, V

    1997-06-01

    Pelvic abscesses are severe complications after rectal surgery. In recent years, surgical drainage has been edged out by percutaneous drainage techniques. We report our experience with the drainage of postoperative pelvic abscesses via the paracoccygeal route controlled by endosonography. In eight patients the diagnosis of a retrorectal pelvic abscess was established by endosonography and confirmed by endosonographically controlled exploratory puncture. Drainage of the abscesses was performed via the paracoccygeal access route by trocar or Seldinger technique under permanent visual control by endoluminal sonography. Irrigation of the abscess cavity was than performed daily. In all cases drainage was successful without complications. Duration of drainage was 9-14 days with a mean of 10.8 days. In one patient there was a recurrence of the abscess because of early removal of the drainage catheter. Because of its overall availability and its good results, paracoccygeal percutaneous endosonographically controlled drainage seems to be a suitable uncomplicated method for drainage of postoperative pelvic abscesses.

  12. [Methods of internal drainage of pancreatic pseudocysts].

    Science.gov (United States)

    Starkov, Yu G; Solodinina, E N; Zamolodchikov, R D

    2016-01-01

    To present own experience of internal drainage and characteristics of its different variants which are applied in various countries. Endosonography-assisted internal drainage of pancreatic pseudocysts was performed in 25 patients. Plastic stents were implanted in one stage without change of instruments while metal stents - with change of instruments during manipulation. Intervention was successful in 24 patients. In 1 case bleeding developed during cystostomy that required open surgery. Plastic and metal stents were used in 11 and 12 patients respectively. 1 patient had two pancreatic pseudocysts. Therefore 2 stents of both types were used in this case. Clinical success was achieved in 91% of cases. Different variants of method resolve problem of surgical approach, stomy and choice of stent. However every technique is targeted to resolve separate problem while single method is not accepted. Further large comparative studies are necessary to define optimal technique of internal drainage.

  13. On the effectiveness of dry drainage in soil salinity control

    Institute of Scientific and Technical Information of China (English)

    WU JingWei; ZHAO LiRong; HUANG JieSheng; YANG JinZhong; VINCENT Bernard; BOUARFA Sami; VIDAL Alain

    2009-01-01

    Dry drainage is thought to be a potential approach to control soil salinity.This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conceptual model and a field experiment.Archived remote sensing images from 1973-2006 were used to delineate the temporal and spatial change of soil salinity.The conceptual water and salt balance model was used to evaluate the role of dry drainage in removing excess salt from the irrigated land.The field experiment was performed to get field validation and give more accurate estimation.The results show that dry drainage did contribute to remove excess salt from the irrigated land and succeed in controlling soil salinity in the Hetao Irrigation District.it can be taken as an alternative approach in (semi-)arid area where artificial drainage is not applicable.

  14. On the effectiveness of dry drainage in soil salinity control

    Institute of Scientific and Technical Information of China (English)

    VINCENT; Bernard; BOUARFA; Sami; VIDAL; Alain

    2009-01-01

    Dry drainage is thought to be a potential approach to control soil salinity. This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conceptual model and a field experiment. Archived remote sensing images from 1973―2006 were used to delineate the temporal and spatial change of soil salinity. The conceptual water and salt balance model was used to evaluate the role of dry drainage in removing excess salt from the irrigated land. The field experiment was performed to get field validation and give more accurate estimation. The results show that dry drainage did contribute to remove excess salt from the irrigated land and succeed in controlling soil salinity in the Hetao Irrigation District. It can be taken as an alternative approach in (semi-)arid area where artificial drainage is not applicable.

  15. Predicting tile drainage discharge

    DEFF Research Database (Denmark)

    Iversen, Bo Vangsø; Kjærgaard, Charlotte; Petersen, Rasmus Jes;

    of the water load coming from the tile drainage system is therefore essential. This work aims at predicting tile drainage discharge using dynamic as well as a statistical predictive models. A large dataset of historical tile drain discharge data, daily discharge values as well as yearly average values were......More than 50 % of Danish agricultural areas are expected to be artificial tile drained. Transport of water and nutrients through the tile drain system to the aquatic environment is expected to be significant. For different mitigation strategies such as constructed wetlands an exact knowledge...... used in the analysis. For the dynamic modelling, a simple linear reservoir model was used where different outlets in the model represented tile drain as well as groundwater discharge outputs. This modelling was based on daily measured tile drain discharge values. The statistical predictive model...

  16. Acid mine drainage

    Science.gov (United States)

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  17. [Argument for choledochostomy, intraoperative endoscopy and external biliary drainage in the treatment of lithiasis of the common bile duct. A 15-year experience].

    Science.gov (United States)

    Suc, B; Fourtanier, G; Escat, J

    1994-01-01

    The treatment of common bile duct stones is controversial. The objective of our study was to report the results of choledochotomy, rigid choledochoscopy and systematic external biliary drainage in the treatment of stones of the common bile duct. Over a 15-year period, 555 patients were operated in our department according to a precise surgical protocol. 14% of these patients were operated as an emergency and 11.8% were operated immediately after endoscopic sphincterotomy. One third of patients suffered from cholangitis. The endoscopic investigation of the common bile duct was positive in 81.5% of patients. The investigation was negative in 18.5% and negative choledochotomy was significantly more frequent in patients operated for acute pancreatitis (p stones were diagnosed in 4.4% of the patients. The presence of residual stones was significantly more frequent in patients with multiple stones of the common bile duct (p asymptomatic. These results, based on a homogeneous therapeutic protocol, can be used as a reference for the evaluation of other techniques, especially endoscopic and laparoscopic techniques.

  18. Physical modeling of transverse drainage mechanisms

    Science.gov (United States)

    Douglass, J. C.; Schmeeckle, M. W.

    2005-12-01

    Streams that incise across bedrock highlands such as anticlines, upwarps, cuestas, or horsts are termed transverse drainages. Their relevance today involves such diverse matters as highway and dam construction decisions, location of wildlife corridors, better-informed sediment budgets, and detailed studies into developmental histories of late Cenozoic landscapes. The transient conditions responsible for transverse drainage incision have been extensively studied on a case-by-case basis, and the dominate mechanisms proposed include: antecedence, superimposition, overflow, and piracy. Modeling efforts have been limited to antecedence, and such the specific erosional conditions required for transverse drainage incision, with respect to the individual mechanisms, remains poorly understood. In this study, fifteen experiments attempted to simulate the four mechanisms and constructed on a 9.15 m long, 2.1 m wide, and 0.45 m deep stream table. Experiments lasted between 50 and 220 minutes. The stream table was filled with seven tons of sediment consisting of a silt and clay (30%) and a fine to coarse sand (70%) mixture. The physical models highlighted the importance of downstream aggradation with regard to antecedent incision versus possible defeat and diversion. The overflow experiments indicate that retreating knickpoints across a basin outlet produce a high probability of downstream flooding when associated with a deep lake. Misters used in a couple of experiments illustrate a potential complication with regard to headward erosion driven piracy. Relatively level asymmetrically sloped ridges allow for the drainage divide across the ridge to retreat from headward erosion, but hindered when the ridge's apex undulates or when symmetrically sloped. Although these physical models cannot strictly simulate natural transverse drainages, the observed processes, their development over time, and resultant landforms roughly emulate their natural counterparts. Proposed originally from

  19. Search for Low-Mass Weakly Interacting Massive Particles Using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Bowles, M. A.; Brandt, D.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Cerdeno, D. G.; Chagani, H.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hertel, S. A.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Kiveni, M.; Koch, K.; Loer, B.; Lopez Asamar, E.; Mahapatra, R.; Mandic, V.; Martinez, C.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Moore, D. C.; Nadeau, P.; Nelson, R. H.; Page, K.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Villano, A. N.; Welliver, B.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2014-01-01

    SuperCDMS is an experiment designed to directly detect Weakly Interacting Massive Particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this paper, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage- assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for 10 live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

  20. CDMSlite: A Search for Low-Mass WIMPs using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment

    CERN Document Server

    Agnese, R; Asai, M; Balakishiyeva, D; Thakur, R Basu; Bauer, D A; Billard, J; Borgland, A; Bowles, M A; Brandt, D; Brink, P L; Bunker, R; Cabrera, B; Caldwell, D O; Cerdeno, D G; Chagani, H; Cooley, J; Cornell, B; Crewdson, C H; Cushman, P; Daal, M; Di Stefano, P C F; Doughty, T; Esteban, L; Fallows, S; Figueroa-Feliciano, E; Godfrey, G L; Golwala, S R; Hall, J; Harris, H R; Hertel, S A; Hofer, T; Holmgren, D; Hsu, L; Huber, M E; Jastram, A; Kamaev, O; Kara, B; Kelsey, M H; Kennedy, A; Kiveni, M; Koch, K; Loer, B; Asamar, E Lopez; Mahapatra, R; Mandic, V; Martinez, C; McCarthy, K A; Mirabolfathi, N; Moffatt, R A; Moore, D C; Nadeau, P; Nelson, R H; Page, K; Partridge, R; Pepin, M; Phipps, A; Prasad, K; Pyle, M; Qiu, H; Rau, W; Redl, P; Reisetter, A; Ricci, Y; Saab, T; Sadoulet, B; Sander, J; Schneck, K; Schnee, R W; Scorza, S; Serfass, B; Shank, B; Speller, D; Villano, A N; Welliver, B; Wright, D H; Yellin, S; Yen, J J; Young, B A; Zhang, J

    2014-01-01

    SuperCDMS is an experiment designed to directly detect Weakly Interacting Massive Particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this paper, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage- assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for 10 live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

  1. A Search for Low-Mass Weakly Interacting Massive Particles Using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Bowles, M. A.; Brandt, D.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Cerdeno, D. G.; Chagani, H.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, Priscilla B.; Daal, M.; Di Stefano, P. C.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, Jeter C.; Harris, H. R.; Hertel, S. A.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Kiveni, M.; Koch, K.; Loer, B.; Lopez Asamar, E.; Mahapatra, R.; Mandic, V.; Martinez, C.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Moore, D. C.; Nadeau, P.; Nelson, R. H.; Page, K.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redi, P.; Reisetter, A.; Ricci, Y.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, Richard; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Villano, A. N.; Welliver, B.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2014-01-27

    SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

  2. 三相电压型PWM整流器的仿真与实验研究%Study of Three-phase PWM Voltage Rectifier's Simulation and Experiment

    Institute of Scientific and Technical Information of China (English)

    赵建勇; 王清灵; 芮秀凤; 刘军华

    2011-01-01

    The paper analyzed the three-phase PWM rectifier's basic principle, and built mathematical model under the three-phase static coordinate axis and rotating coordinate axis. It adopted the closed loop control technology of voltage and circuit, and the control technology of space voltage vector to make up the control system, and studied the influence of variation in load to the system and the principle of energy reversible in rectifier. Finally, it validated the system through the matlab/simulink, and built the experiment system based on TMS2812-DSP. Both the simulation and experiment verify the system has good dynamic and static performance, and nearly to be unit power factor.%分析了三相PWM整流器基本原理,建立了在三相静止坐标系以及两相旋转坐标系中的数学模型.采用电压电流双闭环控制以及空间电压矢量PWM技术构建了控制系统,探究了负载变化对系统的影响,以及整流器能量可逆的原理.最后通过Matlab/Simulink仿真进行了验证,并搭建了基于TMS2812-DSP的实验平台.仿真及实验结果均表明系统具有良好的动、静态性能,且功率因数接近为1.

  3. Experiments investigating the generation and transport of 10--12 MeV, 30-kA, mm-size electron beams with linear inductive voltage adders

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E.

    1997-06-01

    The authors present the design, analysis, and results of the high-brightness electron beam experiments currently under investigation at Sandia National Laboratories. The anticipated beam parameters are the following: 8--12 MeV, 35--50 kA, 30--60 ns FWHM, and 0.5-mm rms beam radius. The accelerators utilized are SABRE and HERMES III. Both are linear inductive voltage adders modified to higher impedance and fitted with magnetically immersed foil less electron diodes. In the strong 20--50 Tesla solenoidal magnetic field of the diode, mm-size electron beams are generated and propagated to a beam stop. The electron beam is field emitted from mm-diameter needle-shaped cathode electrode and is contained in a similar size envelop by the strong magnetic field. These extremely space charge dominated beams provide the opportunity to study beam dynamics and possible instabilities in a unique parameter space. The SABRE experiments are already completed and have produced 30-kA, 1.5-mm FWHM electron beams, while the HERMES-III experiments are on-going.

  4. Accurate Switched-Voltage voltage averaging circuit

    OpenAIRE

    金光, 一幸; 松本, 寛樹

    2006-01-01

    Abstract ###This paper proposes an accurate Switched-Voltage (SV) voltage averaging circuit. It is presented ###to compensated for NMOS missmatch error at MOS differential type voltage averaging circuit. ###The proposed circuit consists of a voltage averaging and a SV sample/hold (S/H) circuit. It can ###operate using nonoverlapping three phase clocks. Performance of this circuit is verified by PSpice ###simulations.

  5. High-precision mass measurements of neutron-deficient Tl isotopes at ISOLTRAP and the development of an ultra-stable voltage source for the PENTATRAP experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Christine

    2015-01-14

    Atomic masses and hence binding energies of nuclides are of great importance for studies of nuclear structure since they reflect all effective interactions in a nucleus. Within this thesis the masses of seven nuclides, namely {sup 194}Au, {sup 194}Hg, {sup 190,193,198}Tl and {sup 202,208}Pb, were determined at the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The thallium region in the chart of isotopes is of special interest due to the occurrence of nuclear structure effects like low-lying isomers, level inversion, shape coexistence and deformations. These effects are investigated by applying finite-difference mass formulas, such as the two-neutron separation energies or the so-called empirical pairing gaps. The second topic addressed within the present thesis is an ultra-stable voltage source, called StaReP (Stable Reference for Penning Trap Experiments), which was developed at the Max-Planck-Institut fuer Kernphysik. It is one of the key components of the high-precision mass spectrometer PENTATRAP, containing a tower of five Penning traps. A 25-channel voltage source with a relative stability of few 10{sup -8} over a period of 10 minutes in the range of 0 to -100V is mandatory for PENTATRAP aiming for mass measurements with relative mass uncertainties of ≤ 10{sup -11}. Mass values with such a high precision allow for stringent tests of quantum electrodynamics in strong electric fields, testing Einstein's mass-energy relation E = mc{sup 2} as well as measurements of decay energies (Q-values) with applications in neutrino physics.

  6. High-voltage picoamperemeter

    Energy Technology Data Exchange (ETDEWEB)

    Bugl, Andrea; Ball, Markus; Boehmer, Michael; Doerheim, Sverre; Hoenle, Andreas; Konorov, Igor [Technische Universitaet Muenchen, Garching (Germany); Ketzer, Bernhard [Technische Universitaet Muenchen, Garching (Germany); Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany)

    2014-07-01

    Current measurements in the nano- and picoampere region on high voltage are an important tool to understand charge transfer processes in micropattern gas detectors like the Gas Electron Multiplier (GEM). They are currently used to e.g. optimize the field configuration in a multi-GEM stack to be used in the ALICE TPC after the upgrade of the experiment during the 2nd long shutdown of the LHC. Devices which allow measurements down to 1pA at high voltage up to 6 kV have been developed at TU Muenchen. They are based on analog current measurements via the voltage drop over a switchable shunt. A microcontroller collects 128 digital ADC values and calculates their mean and standard deviation. This information is sent with a wireless transmitting unit to a computer and stored in a root file. A nearly unlimited number of devices can be operated simultaneously and read out by a single receiver. The results can also be displayed on a LCD directly at the device. Battery operation and the wireless readout are important to protect the user from any contact to high voltage. The principle of the device is explained, and systematic studies of their properties are shown.

  7. Sustainable Drainage Systems

    Directory of Open Access Journals (Sweden)

    Miklas Scholz

    2015-05-01

    Full Text Available Urban water management has somewhat changed since the publication of The Sustainable Drainage System (SuDS Manual in 2007 [1], transforming from building traditional sewers to implementing SuDS, which are part of the best management practice techniques used in the USA and seen as contributing to water-sensitive urban design in Australia. Most SuDS, such as infiltration trenches, swales, green roofs, ponds, and wetlands, address water quality and quantity challenges, and enhance the local biodiversity while also being acceptable aesthetically to the public. Barriers to the implementation of SuDS include adoption problems, flood and diffuse pollution control challenges, negative public perception, and a lack of decision support tools addressing, particularly, the retrofitting of these systems while enhancing ecosystem services. [...

  8. Experiment and Operation of a LHCD-35 kV/2.8 MW/1000 s High-Voltage Power Supply on HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    黄懿赟

    2002-01-01

    A -35 kV/2.8 MW/1000s high-voltage power supply (HVPS) for HT-7 superconducting tokamak has been built successfully. The HVPS is scheduled to run on a 2.45 GHz/1 MW lower hybrid current drive (LHCD) [1] system of HT-7 superconducting tokamak before the set-up of HT-7 superconducting tokamak in 2003. The HVPS has a series of advantages such as good steady and dynamic response, logical computer program controlling the HVPS without any fault, operational panel and experimental board for data acquisition, which both are grounded distinctively in a normative way to protect the main body of HVPS along with its attached equipments from dangers. Electric power cables and other control cables are disposed reasonably, to prevent signals from magnetic interference and ensure the precision of.signal transfer.This paper involves the experiment and operation of a 35 kV/2.8 MW/1000 s HVPS [2] for 2.45 GHz/1 MW LHCD system. The reliability and feasibility of the HVPS has been demonstrated in comparison with experimental results of original design and simulation data.

  9. Infected Baerveldt Glaucoma Drainage Device by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Nurul-Laila Salim

    2015-01-01

    Full Text Available Fungal endophthalmitis is rare but may complicate glaucoma drainage device surgery. Management is challenging as the symptoms and signs may be subtle at initial presentation and the visual prognosis is usually poor due to its resistant nature to treatment. At present there is lesser experience with intravitreal injection of voriconazole as compared to Amphotericin B. We present a case of successfully treated Aspergillus endophthalmitis following Baerveldt glaucoma drainage device implantation with intravitreal and topical voriconazole.

  10. High Voltage Seismic Generator

    Science.gov (United States)

    Bogacz, Adrian; Pala, Damian; Knafel, Marcin

    2015-04-01

    This contribution describes the preliminary result of annual cooperation of three student research groups from AGH UST in Krakow, Poland. The aim of this cooperation was to develop and construct a high voltage seismic wave generator. Constructed device uses a high-energy electrical discharge to generate seismic wave in ground. This type of device can be applied in several different methods of seismic measurement, but because of its limited power it is mainly dedicated for engineering geophysics. The source operates on a basic physical principles. The energy is stored in capacitor bank, which is charged by two stage low to high voltage converter. Stored energy is then released in very short time through high voltage thyristor in spark gap. The whole appliance is powered from li-ion battery and controlled by ATmega microcontroller. It is possible to construct larger and more powerful device. In this contribution the structure of device with technical specifications is resented. As a part of the investigation the prototype was built and series of experiments conducted. System parameter was measured, on this basis specification of elements for the final device were chosen. First stage of the project was successful. It was possible to efficiently generate seismic waves with constructed device. Then the field test was conducted. Spark gap wasplaced in shallowborehole(0.5 m) filled with salt water. Geophones were placed on the ground in straight line. The comparison of signal registered with hammer source and sparker source was made. The results of the test measurements are presented and discussed. Analysis of the collected data shows that characteristic of generated seismic signal is very promising, thus confirms possibility of practical application of the new high voltage generator. The biggest advantage of presented device after signal characteristics is its size which is 0.5 x 0.25 x 0.2 m and weight approximately 7 kg. This features with small li-ion battery makes

  11. Streaming potential during drainage and imbibition

    Science.gov (United States)

    Zhang, Jiazuo; Vinogradov, Jan; Leinov, Eli; Jackson, M. D.

    2017-06-01

    The rock pore space in many subsurface settings is saturated with water and one or more immiscible fluid phases. Examples include nonaqueous phase liquids (NAPLs) in contaminated aquifers, supercritical CO2 during sequestration in deep saline aquifers, the vadose zone, and hydrocarbon reservoirs. Self-potential (SP) and seismoelectric (SE) methods have been proposed to monitor multiphase flow in such settings. However, to properly interpret and model these data requires an understanding of the saturation dependence of the streaming potential. This paper presents a methodology to determine the saturation dependence of the streaming potential coupling coefficient (C) and streaming current charge density (Qs) in unsteady state drainage and imbibition experiments and applies the method to published experimental data. Unsteady state experiments do not yield representative values of C and Qs (or other transport properties such as relative permeability and electrical conductivity) at partial saturation (Sw) because Sw within the sample is not uniform. An interpretation method is required to determine the saturation dependence of C and Qs within a representative elementary volume with uniform saturation. The proposed method makes no assumptions about the pore space geometry. Application of the method to published experimental data from two natural sandstone samples shows that C exhibits hysteresis between drainage and imbibition, can exhibit significant nonmonotonic variations with saturation, is nonzero at the irreducible water saturation, and can exceed the value observed at Sw = 1. Moreover, Qs increases with decreasing Sw but is not given by 1/Sw as is often assumed. The variation in Qs with Sw is very similar for a given sample and a given drainage or imbibition process, and the difference between samples is less than the difference between drainage and imbibition. The results presented here can be used to help interpret SP and SE measurements obtained in partially

  12. Experiment of the nitrogen transformation and transportation in controlled pipe-drainage cotton field%暗管控制排水棉田NO3--N和NH4+-N运移转化试验

    Institute of Scientific and Technical Information of China (English)

    袁念念; 黄介生; 谢华; 黄志强

    2011-01-01

    A filed contrastive experiment project was set up at Drainage and Irrigation Experimental Station, Jingzhou Yajiao to study how controlled pipe-drainage influence the N transformation and transportation. The depth of outlet was fixed through the whole growth period in 2008 and adjusted according to different stages in 2009. The results showed that nitrate concentration in the vertical soil profile decreased with the depth increase. Ammonia concentration had no obvious variation with depth in 2008 and was higher in 20, 40 cm layers than that in 60, 80 cm layers. Nitrate concentration was higher in surface and 20 cm layers in controlled treatments. Ammonia concentration was higher in the same layers in controlled treatments than that in conditional treatment. The ratio between nitrate and ammonia concentration was larger in 2008 than that in 2009. Adjusting the depth of the drainage outlet according to the growth stages could keep the nitrogen content more stable than fixing the depth in the whole growth period, and reduce nitrogen losses.%为了研究控制排水条件下土壤剖面NH4+-N和NO3--N之间的转化运移规律,2008、2009年在荆州丫角排灌试验站棉花生育期内进行大田暗管控制排水对比试验:2008年全生育期内固定排水出口埋深、2009年分生育阶段调整出口埋深.结果发现:无论调整出口埋深与否,NO3--N含量在土壤垂直剖面上都随土层深度增加而减少.Nn4+-N含量2008年随土层深度增加无明显变化规律、2009年在20、40 cm处较60、80 cm高.控制排水小区表层和20 cm土层NO3--N含量较自由排水小区高;同层土控制排水小区NH4+-N含量比自由排水小区高.2008年各处理NO3--N含量高于2009年,NH3+-N含量低于2009年,NO3--N与NH4+-N同层土平均含量之比大于2009年.分生育阶段调整排水出口埋深可减小田间地下水位波动,更能使田间氮素形态稳定、减少氮素流失.

  13. Three-generation experiment showed female C57BL/6J mice drink drainage canal water containing low level of TCDD-like activity causing high pup mortality.

    Science.gov (United States)

    Huang, Li; Huang, Ren; Ran, Xin-Ru; Liu, Han-Ying; Zhang, Yu; Dai, Li-Jun; Li, Bing

    2011-01-01

    2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), polychlorinated biphenyls (PCBs) and similar compounds are toxic to animals and humans. Based on a yeast reporter system, AhR-activating ligands similar in concentration to 2 ng/l of TCDD were detected in two canal waters in Guangzhou, China. In this study, a three-generation experiment was conducted to assess the reproductive and developmental risks associated with these waters in C57BL/6J female mice, including female reproduction, pup indices, reproductive hormone levels, and levels of AhR, ARNT, and CYP1A2 in the uterus. Similar reproductive toxic effects were produced in the offspring of mice that drank the canal water as would occur if they drank 2 ng/l/day TCDD. The major reproductive indices that were affected included mating time and gestation length over all the generations. A striking finding is the TCDD (2 ng/l) and the water samples significantly reduced Day 4 pup survival rates in the F2 and F3. Both TCDD exposure and drinking canal water decreased estradiol-17β (E2) levels in the multiparous females and decreased follicle-stimulating hormone (FSH), luteinizing hormone (LH) and E2 levels in the virgin females. Immunochemical staining revealed that the AhR and CYP1A2 positive signals were enhanced, and the ARNT positive signal was weakened in the uteri of mice drinking water with TCDD (2 ng/l) and the canal water samples. These results imply that the canal water contains AhR ligands that could induce similar toxic effects as do low levels of TCDD. Exposure to these contaminants can significantly impair the reproductive health of female mice. Considering this canals are open directly to Pearl River, whether these effects could be caused in human reproduction and development warrants further study.

  14. Filter Fabrics for Airport Drainage.

    Science.gov (United States)

    1979-09-01

    Systems for *r- field Pavements," Harry R. Cedergren . d. "Development of Guidelines for the Design of Subsurfac( Drainage Systems for Highway Pavement...Structural 4Sectic s," H. R. Cedergren , J. A. Arman, and K. H. O’Brien. e. Drainage of Highway and Airfield Pavements, Harry R. Cedergren .> Five...by Cedergren (974).5 Additionally, several references were used, particularly those describing experimental anu construction prolects using filter

  15. Drainage pits in cohesionless materials: implications for surface of Phobos.

    Science.gov (United States)

    Horstman, K C; Melosh, H J

    1989-09-10

    Viking orbiter images show grooves and chains of pits crossing the surface of Phobos, many of which converge toward the large crater Stickney or its antipode. Although it has been proposed that the pits and grooves are chains of secondary craters, their morphology and geometric relations suggest that they are the surface traces of fractures in the underlying solid body of Phobos. Several models have been proposed to explain the pits, of which the most plausible are gas venting and drainage of regolith into open fractures. the latter mechanism is best supported by the image data and is the mechanism studied in this investigation. Drainage pits and fissures are modeled experimentally by using two rigid substrate plates placed edge to edge and covered by uniform thicknesses of dry fragmental debris (simulated regolith). Fracture extension is simulated by drawing the plates apart, allowing drainage of regolith into the newly created void. A typical drainage experiment begins with a shallow depression on the surface of the regolith, above the open fissure. Increased drainage causes local drainage pits to form; continued drainage causes the pits to coalesce, forming a cuspate groove. The resulting experimental patterns of pits and grooves have pronounced similarities to those observed on Phobos. Characteristics such as lack of raised rims, linearity of grooves and chains of pits, uniform spacing of pits, and progression from discrete pits to cuspate grooves are the same in the experiments and on Phobos. In contrast, gas-venting pits occur in irregular chains and have raised rims. These experiments thus indicate that the Phobos grooves and pits formed as drainage structures. The pit spacing in an experiment is measured at the time that the maximum number of pits forms, prior to groove development. The average pit spacing is compared to the regolith thickness for each material. Regression line fits indicate that the average spacing of drainage pits in unconsolidated

  16. A matter of quantum voltages.

    Science.gov (United States)

    Sellner, Bernhard; Kathmann, Shawn M

    2014-11-14

    Voltages inside matter are relevant to crystallization, materials science, biology, catalysis, and aqueous chemistry. The variation of voltages in matter can be measured by experiment, however, modern supercomputers allow the calculation of accurate quantum voltages with spatial resolutions of bulk systems well beyond what can currently be measured provided a sufficient level of theory is employed. Of particular interest is the Mean Inner Potential (V(o))--the spatial average of these quantum voltages referenced to the vacuum. Here we establish a protocol to reliably evaluate V(o) from quantum calculations. Voltages are very sensitive to the distribution of electrons and provide metrics to understand interactions in condensed phases. In the present study, we find excellent agreement with measurements of V(o) for vitrified water and salt crystals and demonstrate the impact of covalent and ionic bonding as well as intermolecular/atomic interactions. Certain aspects in this regard are highlighted making use of simple model systems/approximations. Furthermore, we predict V(o) as well as the fluctuations of these voltages in aqueous NaCl electrolytes and characterize the changes in their behavior as the resolution increases below the size of atoms.

  17. Transient Voltage Recorder

    Science.gov (United States)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

    2002-01-01

    A voltage transient recorder can detect lightning induced transient voltages. The recorder detects a lightning induced transient voltage and adjusts input amplifiers to accurately record transient voltage magnitudes. The recorder stores voltage data from numerous monitored channels, or devices. The data is time stamped and can be output in real time, or stored for later retrieval. The transient recorder, in one embodiment, includes an analog-to-digital converter and a voltage threshold detector. When an input voltage exceeds a pre-determined voltage threshold, the recorder stores the incoming voltage magnitude and time of arrival. The recorder also determines if its input amplifier circuits clip the incoming signal or if the incoming signal is too low. If the input data is clipped or too low, the recorder adjusts the gain of the amplifier circuits to accurately acquire subsequent components of the lightning induced transients.

  18. Automated Voltage Control in LHCb

    CERN Document Server

    Granado Cardoso, L; Jacobsson, R

    2011-01-01

    LHCb is one of the 4 LHC experiments. In order to ensure the safety of the detector and to maximize efficiency, LHCb needs to coordinate its own operations, in particular the voltage configuration of the different subdetectors, according to the accelerator status. A control software has been developed for this purpose, based on the Finite State Machine toolkit and the SCADA system used for control throughout LHCb (and the other LHC experiments). This software permits to efficiently drive both the Low Voltage (LV) and High Voltage (HV) systems of the 10 different sub-detectors that constitute LHCb, setting each sub-system to the required voltage (easily configurable at run-time) based on the accelerator state. The control software is also responsible for monitoring the state of the Sub-detector voltages and adding it to the event data in the form of status-bits. Safe and yet flexible operation of the LHCb detector has been obtained and automatic actions, triggered by the state changes of the ...

  19. DRAINAGE AND FLEXIBLE PAVEMENT PERFORMANCE

    Directory of Open Access Journals (Sweden)

    SIDDHARTHA ROKADE

    2012-04-01

    Full Text Available Providing adequate drainage to a pavement system has been considered as an important design consideration to prevent premature failures due to water related problems such as pumping action, loss of support, and rutting, among others. Most water in pavements is due to rainfall infiltration into unsaturated pavement layers, throughjoints, cracks, shoulder edges, and various other defects, especially in older deteriorated pavements. Water also seep upward from a high groundwater table due to capillary suction or vapour movements, or it may flow laterally from the pavement edges and side ditches. Providing adequate drainage to a pavement system has been considered as an important design consideration to ensure satisfactory performance of the pavement, particularly from the perspective of life cycle cost and serviceability. To minimize premature pavement distresses and to enhance the pavement performance, it is imperative to provide adequate drainage to allow infiltrated water to drain out from the base and sub-base, thus avoiding saturation of base and subgrade soils. This paper deals with the analysis of the impact of subsurface drainage on pavement system performance. The requirement ofeffective subsurface drainage for pavement performance is also discussed.

  20. Drainage filter technologies to mitigate site-specific phosphorus losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Iversen, Bo Vangsø

    2014-01-01

    of implementing the drainage filter technologies including surface-flow constructed wetlands, subsurface flow constructed wetlands, and drainage well filters (www.supremetech.dk). We will present results on P retention from (i) controlled column experiments with permeable filter substrates, and (ii) a full......-scale surface-flow constructed wetland. In the former, various natural and industrial P filter substrates have been tested for their ability to reduce inlet P concentrations to below environmental threshold values (... on laboratory experiments and field scale monitoring, the different filter technology approaches will be compared and evaluated from a case study perspective....

  1. Technical note on drainage systems

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby

    This technical note will present simple but widely used methods for the design of drainage systems. The note will primarily deal with surface water (rainwater) which on a satisfactorily way should be transport into the drainage system. Traditional two types of sewer systems exist: A combined system......’s not major different than described below - just remember to include this contribution for combined systems where the surface water (rain) and sewage are carried in the same pipes in the system and change some of the parameters for failure allowance (this will be elaborated further later on). The technical...

  2. Automatic voltage imbalance detector

    Science.gov (United States)

    Bobbett, Ronald E.; McCormick, J. Byron; Kerwin, William J.

    1984-01-01

    A device for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

  3. Mixed voltage VLSI design

    Science.gov (United States)

    Panwar, Ramesh; Rennels, David; Alkalaj, Leon

    1993-01-01

    A technique for minimizing the power dissipated in a Very Large Scale Integration (VLSI) chip by lowering the operating voltage without any significant penalty in the chip throughput even though low voltage operation results in slower circuits. Since the overall throughput of a VLSI chip depends on the speed of the critical path(s) in the chip, it may be possible to sustain the throughput rates attained at higher voltages by operating the circuits in the critical path(s) with a high voltage while operating the other circuits with a lower voltage to minimize the power dissipation. The interface between the gates which operate at different voltages is crucial for low power dissipation since the interface may possibly have high static current dissipation thus negating the gains of the low voltage operation. The design of a voltage level translator which does the interface between the low voltage and high voltage circuits without any significant static dissipation is presented. Then, the results of the mixed voltage design using a greedy algorithm on three chips for various operating voltages are presented.

  4. Clinical experience of treating superior anorectal abscess with thread drainage technique%挂线引流法治疗高位肛管直肠周围脓肿的临床观察

    Institute of Scientific and Technical Information of China (English)

    吴显保; 史仁杰

    2013-01-01

    Objective:To evaluate the clinical efficacy, postoperative pain,anal sphincter defects and scores of anal function in patients with superior anorectal abscess managed with thread drainage technique . Methods: One hundred patients with upper anorectal abscess were equal-ly allocated to two groups and treated with either thread drainage tech-nique or one step incision thread-drawing method.The two groups were observed regarding the curative effects,duration of wound healing,postop-erative pain,incidence of anal sphincter defects and scores of anal func-tion.Results: The short-term curative rates were 100% for both experi-mental and control groups.Follow-up over half a year time showed that the long-term curative rate was 96.2%(25/26) for the experimental group and 100%(23/23)for the controls,yet the two groups were not statistical-ly different(χ2 =0.004,P>0.05).The wound healing time was shorter and the average scores of postoperative pain was lower in the experimental group than the control group(24.20 ±1.97 d vs.26.20 ±2.30 d)(1.94 ±0.71 vs.2.72 ±0.81)(t=4.667,P<0.01; t=5.118,P<0.01,re-spectively) .No incidence of obvious leakage discharge and keyhole-like deformity occurred postoperatively in the experimental group ,yet such in-cidence was seen in the control group( n=16) .The two groups were sig-nificantly different(χ2 =51.515,P<0.01).By Wexner scale for postop-erative anal incontinence,the score was 0.56 ±0.50 for the experimental group and 1.34 ±0.63 for the controls ( t =6.935, P <0.01 ). Conclusion: The two approaches to upper anorectal abscess are compara-ble concerning the curative effects and course of treatment ,yet the postop-erative pain,incidence of anal sphincter defects and anal function scores seem superior in application of thread drainage to one step incision thread-drawing method.%目的:研究挂线引流法治疗高位肛管直肠周围脓肿的临床疗效及其对术后疼痛、肛管缺损和肛门功能评分的影响。方法:

  5. A Study of the Effect of Gold Thickness Distribution in the Jet Plating Process to Optimize Gold Usage and Plating Voltage Using Design of Experiments

    OpenAIRE

    Aramphongphun Chuckaphun; Nampanya Chalermpol

    2016-01-01

    A gold plating process in the electronics industry can be classified as (i) all surface plating or (ii) selective plating. Selective plating is more widely used than all surface plating because it can save more gold used in the plating process and takes less plating time. In this research, the selective plating process called jet plating was studied. Factors that possibly affected the gold usage and plating voltage were also studied to reduce the production cost. These factors included (a) pl...

  6. Design and experiment of 4H-SiC JBS diodes achieving a near-theoretical breakdown voltage with non-uniform floating limiting rings terminal

    Science.gov (United States)

    Yuan, Hao; Song, Qingwen; Tang, Xiaoyan; Zhang, Yimeng; Zhang, Yimen; Zhang, Yuming

    2016-09-01

    In this paper, a 4H-SiC Junction Barrier Schottky diode (JBS) with non-uniform floating limiting rings (FLRs) has been investigated and fabricated using n type 4H-SiC epitaxial layer with thickness of 31 μm and doping concentration of 3.3 × 1015 cm-3. According to the simulated results, the key parameters of a FLRs design to achieve a high voltage are the minimum space between two adjacent doped rings, spacing growth step and number of rings. The experimental results also show a great agreement with simulated results. Meanwhile, a near-ideal breakdown voltage of 3.7 kV was achieved, which yield around 95% of the parallel-plane breakdown voltage. The forward characteristics show that the fabricated JBS diodes have a forward current density of 210 A/cm2 at 3 V and a specific on-resistance (Rsp-on) of 7.58 mΩ cm2. Different FLRs parameters have no effect on the forward device performance.

  7. 持续腰大池引流术在颅脑外科患者中应用体会%Application experience of continuous lumbar cistern drainage in craniocerebral surgery patients

    Institute of Scientific and Technical Information of China (English)

    李佰涛; 陈春林; 孙杰; 陈力行

    2015-01-01

    Objective To investigate the application effect of continuous lumbar cistern drainage in craniocerebral surgery patients.Methods A total of 65 craniocerebral surgery patients received continuous lumbar cistern drainage. Observation was made on drainage success rate, catheterization time, drainage volume, complications and cure rate.Results All the 65 cases received successful drainage. The average catheterization time in cerebral contusion and laceration complicated with traumatic sabarachnoid cavity hemorrhage was (7.1±1.2) d, and the average drainage volume was (244.2±21.5) ml/d. The average catheterization time in encephaledema after cerebral hemorrhage was (6.4±1.1) d, and the average drainage volume was (238.5±27.2) ml/d. The average catheterization time in encephaledema after craniotomy for severe craniocerebral injury was(6.6±1.3) d, and the average drainage volume was (241.6±25.0) ml/d. All the 65 patients had relieved clinical symptoms after operation, without any complications. Their cure rate was 100%.Conclusion Continuous lumbar cistern drainage provides good effect and high drainage success rate in the treatment of craniocerebral surgery patients. This method can effective relieve disease, and it is worth promoting.%目的 探讨持续腰大池引流术在颅脑外科患者中的应用效果.方法 65例颅脑外科患者, 均给予持续腰大池引流术, 观察引流成功率、置管时间、引流量、并发症、治愈率等.结果 65例患者均顺利完成引流, 其中脑挫裂伤合并外伤性蛛网膜下腔出血平均置管时间为(7.1±1.2)d, 平均引流量为(244.2±21.5)ml/d;脑出血后脑水肿平均置管时间为(6.4±1.1)d, 平均引流量为(238.5±27.2)ml/d;重型颅脑损伤开颅术后脑水肿平均置管时间为(6.6±1.3)d, 平均引流量为(241.6±25.0)ml/d.65例患者术后均缓解临床症状, 无并发症的发生, 治愈率为100%.结论 持续腰大池引流术在颅脑外科患者中治疗效果佳,

  8. Percutaneous drainage of abdominal abcess

    Energy Technology Data Exchange (ETDEWEB)

    Men, Sueleyman E-mail: suleyman.men@deu.edu.tr; Akhan, Okan; Koeroglu, Mert

    2002-09-01

    The mortality in undrained abdominal abscesses is high with a mortality rate ranging between 45 and 100%. The outcome in abdominal abscesses, however, has improved due to advances in image guided percutaneous interventional techniques. The main indications for the catheter drainage include treatment or palliation of sepsis associated with an infected fluid collection, and alleviation of the symptoms that may be caused by fluid collections by virtue of their size, like pancreatic pseudocele or lymphocele. The single liver abscesses may be drained with ultrasound guidance only, whereas the multiple abscesses usually require computed tomography (CT) guidance and placement of multiple catheters. The pancreatic abscesses are generally drained routinely and urgently. Non-infected pancreatic pseudocysts may be simply observed unless they are symptomatic or cause problems such as pain or obstruction of the biliary or the gastrointestinal tract. Percutaneous routes that have been described to drain pelvic abscesses include transrectal or transvaginal approach with sonographic guidance, a transgluteal, paracoccygeal-infragluteal, or perineal approach through the greater sciatic foramen with CT guidance. Both the renal and the perirenal abscesses are amenable to percutaneous drainage. Percutaneous drainage provides an effective and safe alternative to more invasive surgical drainage in most patients with psoas abscesses as well.

  9. 微创穿刺引流术治疗高血压脑出血患者的护理体会%Nursing experience of patients with hypertensive cerebral hemorrhage treated by minimally invasive puncture drainage

    Institute of Scientific and Technical Information of China (English)

    王力伟; 李学良; 周晓满; 湛金梅; 郝晓; 付刚; 史琳

    2014-01-01

    目的:总结32例高血压脑出血患者行微创穿刺引流术的护理经验。方法应用微创颅内血肿粉碎穿刺针对32例高血压脑出血患者进行血肿抽吸、粉碎冲洗、液化及引流,并采取积极的术前及术后护理方法。结果本组治愈16例(50%),显著进步8例(25%),进步4例(12.5%),无变化2例(6.25%),死亡2例(6.25%),总有效率为87.5%。结论微创颅内血肿穿刺术治疗高血压脑出血疗效确切,加强基础护理、密切监测病情、预防和及时发现潜在并发症、及早进行康复锻炼、家庭访视,对患者预后起着积极作用,可提高患者生活质量。%Objective To summarize the experience of 32 patients with hypertensive cere-bral hemorrhage treated by minimally invasive puncture drainage.Methods Minimally invasive intracranial hematoma needle was used to pump,crush and flush,liquidate and drain hematoma. There were 16 cured cases (50%),8 improved cases (25%),4 progressive cases (12.5%),2 un-changed cases (6.25%)and 2 died patients (6.25%),the total effective rate was 87.5%.Con-clusion Minimally invasive treatment of intracranial hematoma puncture for hypertensive cerebral hemorrhage could strengthen basic nursing,closely monitor of the disease,prevent and timely de-tect potential complications,early do rehabilitation exercises,conduct home visits early.So it could promote the prognosis of patients and enhance the quality of life of patients.

  10. Definition of the drainage filter problem

    NARCIS (Netherlands)

    Zaslavsky, D.

    1977-01-01

    It is common to consider the following: I. Retention of soil particles that may enter the drainage pipe and cause its clogging. For some sensitive structures it is important to prevent settlements due to soil transportation by drainage water.

  11. 生态景观型灌排系统面源污染防治试验及生态响应%Non-point source pollution control experiment and ecological response of ecological landscape type irrigation and drainage system

    Institute of Scientific and Technical Information of China (English)

    张雅杰; 邵庆军; 李海彩; 叶梁倩; 姚星; 胡将军

    2015-01-01

    The current irrigation and drainage system in land renovation was mainly designed and constructed to heighten efficiency of irrigation and drainage, structure safety and convenient management, which, however, somewhat neglected ecological landscape design, exerting an inappropriate influence on the biological habitat and agricultural non-point source pollution. Therefore, the aim of this paper is to design an ecological landscape irrigation and drainage system and realize more comprehensive benefits. First of all, originated from the traditional agricultural drainage and irrigation system, irrigation and drainage with an ecological ring-ditch was designed by using the principle of mutually-beneficial symbiosis of paddy, red duckweed, fish and vegetable planting plates, which realized the multifunctional stereo development of rice paddy pisciculture, vegetable planting and so on. Meanwhile, the roundabout biochemical pond was designed at the ecological ring-ditch drainage sluice, which was used as the treatment device of agricultural non-point source pollution. Then, ecological landscape lateral canal and lateral ditch was designed, which was made up of vegetation type diaphragm blocks, hornworts, vegetable planting plates, fish, Jumping type antiskid ecological plate and plant ecological community. What is more, by using the land reclamation project in shanghai as the experimental area, the rice growth cycle (6-10 months) as study period, the COD, NH4+-N, TN and TP as test indicators, and three monitoring sections as monitoring points, experimental of non-point source pollution prevention effects were made comparisons between system 1, system 2 and system3. The system 1 was constituted by the irrigation and drainage system using ecological ring-ditch, roundabout biochemical pond and lateral ditch wetlands. The system 2 was constituted by the irrigation and drainage system using underground pipe and current lateral ditch. And the system 3 was constituted by the

  12. Robust options to remove nitrate and phosphate from tile drainage

    NARCIS (Netherlands)

    Jansen, Stefan; Gerritse, Jan; Stuurman, Roelof; Chardon, W.J.; Talens, René

    2016-01-01

    Diffuse emission from agricultural land is a major, persistent source of nitrogen and phosphorus in surface waters. In this contribution, we present field experiments of a series of robust options to remove nitrate and phosphorus at
    field drainage level. Nitrate removal was enhanced by stimulati

  13. Percutaneous catheter drainage of intrapulmonary fluid collection

    Energy Technology Data Exchange (ETDEWEB)

    Park, E. D.; Kim, H. J.; Choi, P. Y.; Jung, S. H. [Gyeongsang National University Hospital, Chinju (Korea, Republic of)

    1994-01-15

    With the success of percutaneous abdominal abscess drainage, attention is now being focused on the use of similar techniques in the thorax. We studied to evaluate the effect of percutaneous drainage in parenchymal fluid collections in the lungs. We performed percutaneous drainage of abscesses and other parenchymal fluid collections of the lungs in 15 patients. All of the procedures were performed under the fluoroscopic guidance with an 18-gauge Seldinger needle and coaxial technique with a 8-10F drainage catheter. Among 10 patients with lung abscess, 8 patients improved by percutaneous catheter drainage. In one patient, drainage was failed by the accidental withdrawal of the catheter before complete drainage. One patient died of sepsis 5 hours after the procedure. Among three patients with complicated bulla, successful drainage was done in two patients, but in the remaining patient, the procedure was failed. In one patient with intrapulmonary bronchogenic cyst, the drainage was not successful due to the thick internal contents. In one patient with traumatic hematoma, after the drainage of old blood clots, the signs of infection disappeared. Overally, of 14 patients excluding one who died, 11 patients improved with percutaneous catheter drainage and three patients did not. There were no major complications during and after the procedure. We conclude that percutaneous catheter drainage is effective and safe procedure for the treatment of parenchymal fluid collections of the lung in patients unresponsive to the medical treatment.

  14. Nursing experience of pipeline after drainage of lumbar cistern in Primary hospital%基层医院行腰大池引流术后管路的护理体会

    Institute of Scientific and Technical Information of China (English)

    周晓华

    2014-01-01

    In the nursing of lumbar cistern drainage tube,founding the tube nursing quality control group, doing the good nursing of drainage tube,preventing unplanned extubation,and disinfecting and isolating it strictly are the effective measures.They can promote early rehabilitation of patients.%在行腰大池引流置管护理时,成立管路护理质控小组,做好引流管护理,防止非计划性拔管,严格消毒隔离管路,是行之有效的措施,能促进患者早日康复。

  15. Basinsoft, a computer program to quantify drainage basin characteristics

    Science.gov (United States)

    Harvey, Craig A.; Eash, David A.

    2001-01-01

    Surface water runoff is a function of many interrelated factors including climate, soils, landuse, and the physiography of the drainage basin. A practical and effective method to quantify drainage basin characteristics would allow analysis of the interrelations of these factors, leading to an improved understanding of the effects of drainage basin characteristics on surface-water runoff. Historically, the quantification of drainage basin characteristics has been a tedious and time-consuming process. Recent improvements in computer hardware and software technology have enabled the developers of a program called Basinsoft to automate this process. Basinsoft requires minimal preprocessing of data and provides an efficient, automated procedure for quantifying selected morphometric characteristics and the option to area-weight characteristics for a drainage basin. The user of Basinsoft is assumed to have a limited amount of experience in the use of ARC/INFO, a proprietary geographic information system (GIS). (The use of brand names in this chapter is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey [USGS].)

  16. Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes

    Energy Technology Data Exchange (ETDEWEB)

    Grin, A. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)

    2014-09-01

    The goal of this research is to provide durable and long-term water management solutions using exterior insulating sheathing as part of the water management system. It is possible to tape or seal the joints in insulating sheathing to create a drainage plane and even an air control layer. There exists the material durability component of the tape as well as the system durability component being the taped insulating sheathing as the drainage plane. This measure guideline provides best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant issues were discussed with the group, which are required to make taped insulating sheathing a simple, long-term, and durable drainage plane: horizontal joints should be limited or eliminated wherever possible; where a horizontal joint exists use superior materials; and frequent installation inspection and regular trade training are required to maintain proper installation.

  17. Experience on lumbar cistern tube drainage and intrathecal injection in the treatment of intracranial infection%腰大池置管引流加鞘内注射治疗颅内感染的体会

    Institute of Scientific and Technical Information of China (English)

    阿扎提; 郑鹏; 刘德全

    2014-01-01

    目的:探讨腰大池置管持续引流结合鞘内注射治疗颅脑外伤及开颅术后所致颅内感染的效果。方法:2009年5月-2014年5月颅脑外伤及开颅手术后颅内感染患者7例,应用腰大池置管持续外引流结合鞘内注射治疗。观察其疗效。结果:引流7~12 d,临床治愈6例,1例并发全脑室炎死亡。结论:颅脑外伤及开颅术后出现颅内感染的患者在全身应用敏感抗生素的前提下可采用腰大池置管持续外引流结合鞘内注射,该方法简便、安全、疗效肯定。%Objective:To investigate the therapeutic effect of lumbar cistern tube drainage and intrathecal injection in the treatment of intracranial infection caused by craniocerebral trauma and craniotomy.Methods:7 cases of intracranial infection caused by craniocerebral trauma and craniotomy were selected from May 2009 to May 2014.They were treated with lumbar cistern tube drainage and intrathecal injection.Observe the effect.Results:They were drainaged for 7~12 days.6 cases were cured.1 case complicated with full ventriculitis death.Conclusion:Patients with intracranial infection caused by craniocerebral trauma and craniotomy can be given lumbar cistern tube drainage and intrathecal injection under the premise of systemic application of sensitive antibiotic.This method is simple,safety and efficacy.

  18. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  19. Technological Aspects: High Voltage

    CERN Document Server

    Faircloth, D C

    2013-01-01

    This paper covers the theory and technological aspects of high-voltage design for ion sources. Electric field strengths are critical to understanding high-voltage breakdown. The equations governing electric fields and the techniques to solve them are discussed. The fundamental physics of high-voltage breakdown and electrical discharges are outlined. Different types of electrical discharges are catalogued and their behaviour in environments ranging from air to vacuum are detailed. The importance of surfaces is discussed. The principles of designing electrodes and insulators are introduced. The use of high-voltage platforms and their relation to system design are discussed. The use of commercially available high-voltage technology such as connectors, feedthroughs and cables are considered. Different power supply technologies and their procurement are briefly outlined. High-voltage safety, electric shocks and system design rules are covered.

  20. Stray voltage mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Jamali, B.; Piercy, R.; Dick, P. [Kinetrics Inc., Toronto, ON (Canada). Transmission and Distribution Technologies

    2008-04-09

    This report discussed issues related to farm stray voltage and evaluated mitigation strategies and costs for limiting voltage to farms. A 3-phase, 3-wire system with no neutral ground was used throughout North America before the 1930s. Transformers were connected phase to phase without any electrical connection between the primary and secondary sides of the transformers. Distribution voltage levels were then increased and multi-grounded neutral wires were added. The earth now forms a parallel return path for the neutral current that allows part of the neutral current to flow continuously through the earth. The arrangement is responsible for causing stray voltage. Stray voltage causes uneven milk production, increased incidences of mastitis, and can create a reluctance to drink water amongst cows when stray voltages are present. Off-farm sources of stray voltage include phase unbalances, undersized neutral wire, and high resistance splices on the neutral wire. Mitigation strategies for reducing stray voltage include phase balancing; conversion from single to 3-phase; increasing distribution voltage levels, and changing pole configurations. 22 refs., 5 tabs., 13 figs.

  1. High voltage test techniques

    CERN Document Server

    Kind, Dieter

    2001-01-01

    The second edition of High Voltage Test Techniques has been completely revised. The present revision takes into account the latest international developments in High Voltage and Measurement technology, making it an essential reference for engineers in the testing field.High Voltage Technology belongs to the traditional area of Electrical Engineering. However, this is not to say that the area has stood still. New insulating materials, computing methods and voltage levels repeatedly pose new problems or open up methods of solution; electromagnetic compatibility (EMC) or components and systems al

  2. Mitigation of Unbalanced Voltage Sags and Voltage Unbalance in CIGRE Low Voltage Distribution Network

    OpenAIRE

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Mahat, Pukar; Cecati, Carlo

    2013-01-01

    Any problem with voltage in a power network is undesirable as it aggravates the quality of the power. Power electronic devices such as Voltage Source Converter (VSC) based Static Synchronous Compensator (STATCOM) etc. can be used to mitigate the voltage problems in the distribution system. The voltage problems dealt with in this paper are to show how to mitigate unbalanced voltage sags and voltage unbalance in the CIGRE Low Voltage (LV) test network and net-works like this. The voltage unbala...

  3. EUS-Guided Biliary Drainage

    Directory of Open Access Journals (Sweden)

    Marc Giovannini

    2012-01-01

    Full Text Available The echoendoscopic biliary drainage is an option to treat obstructive jaundices when ERCP drainage fails. These procedures compose alternative methods to the side of surgery and percutaneous transhepatic biliary drainage, and it was only possible by the continuous development and improvement of echoendoscopes and accessories. The development of linear setorial array echoendoscopes in early 1990 brought a new approach to diagnostic and therapeutic dimenion on echoendoscopy capabilities, opening the possibility to perform punction over direct ultrasonographic view. Despite of the high success rate and low morbidity of biliary drainage obtained by ERCP, difficulty could be found at the presence of stent tumor ingrown, tumor gut compression, periampulary diverticula, and anatomic variation. The echoendoscopic technique starts performing punction and contrast of the left biliary tree. When performed from gastric wall, the access is made through hepatic segment III. From duodenum, direct common bile duct punction. Dilatation is required before stent introduction, and a plastic or metallic stent is introduced. This phrase should be replaced by: diathermic dilatation of the puncturing tract is required using a 6F cystostome. The technical success of hepaticogastrostomy is near 98%, and complications are present in 36%: pneumoperitoneum, choleperitoneum, infection, and stent disfunction. To prevent bile leakage, we have used the 2 stent techniques, the first stent introduced was a long uncovered metallic stent (8 or 10 cm, and inside this first stent a second fully covered stent of 6 cm was delivered to bridge the bile duct and the stomach. Choledochoduodenostomy overall success rate is 92% and described complications include, in frequency order, pneumoperitoneum and focal bile peritonitis, present in 19%. By the last 10 years, the technique was especially performed in reference centers, by ERCP experienced groups, and this seems to be a general

  4. Exploring Agricultural Drainage's Influence on Wetland and ...

    Science.gov (United States)

    Artificial agricultural drainage (i.e. surface ditches or subsurface tile) is an important agricultural management tool. Artificial drainage allows for timely fieldwork and adequate root aeration, resulting in greater crop yields for farmers. This practice is widespread throughout many regions of the United States and the network of artificial drainage is especially extensive in flat, poorly-drained regions like the glaciated Midwest. While beneficial for crop yields, agricultural drains often empty into streams within the natural drainage system. The increased network connectivity may lead to greater contributing area for watersheds, altered hydrology and increased conveyance of pollutants into natural water bodies. While studies and models at broader scales have implicated artificial drainage as an important driver of hydrological shifts and eutrophication, the actual spatial extent of artificial drainage is poorly known. Consequently, metrics of wetland and watershed connectivity within agricultural regions often fail to explicitly include artificial drainage. We use recent agricultural census data, soil drainage data, and land cover data to create estimates of potential agricultural drainage across the United States. We estimate that agricultural drainage in the US is greater than 31 million hectares and is concentrated in the upper Midwest Corn Belt, covering greater than 50% of available land for 114 counties. Estimated drainage values for numerous countie

  5. Microbial decontamination of uranium mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Hard, B.C.; Babel, W. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Leipzig (Germany)

    2001-07-01

    One of the problems one is faced with when uranium mines are closed is the decontamination of acid mine drainage (AMD) from tailings and flooding of the underground mines. The high concentrations of sulfates and metals in mining water make it impossible to dispose of the water into rivers without having to decontaminate it first. A bioremediation process is proposed in which sulfate-reducing bacteria are used to remove metals, neutralize the water and reduce the sulfate concentrations. Methylotrophic sulfate-reducing strains have been isolated which can be used in such a process. Lab scale experiments with different reactor types were carried out in order to find the optimum design for this bioremediation process. Comparisons were made between methanol and other electron donors with regards to their suitability as substrate for this process. Methanol was found to be most suited. Laboratory data suggest that immobilizing the bacteria on pumice particles increases the sulfate-reduction rate (SRR) up to three fold to 18 mg/l.h, compared to the rates of free flowing cells of between 3.7 and 6.8 mg/l.h. Preliminary experiments on a larger scale (15 l) using acid mine drainage pH 2.5 show SRR of 0.71 mg/l.h. In biosorption experiments up to 140 mg of aluminium per g biomass was removed from the water. One strain was found to reduce uranium VI, thus changing it from the soluble to the insoluble form. The application of the proposed process with regards to bioremediation of AMD are discussed. (orig.)

  6. Clinical experience of improved minimally invasive puncture drainage in the treatment of basal ganglia hemorrhage using soft drainage tube%改良软通道微创穿刺引流治疗基底节血肿的临床体会

    Institute of Scientific and Technical Information of China (English)

    丁根华; 赖小军; 夏侯海峰

    2014-01-01

    目的:探讨改良软通道微创穿刺引流治疗基底节血肿的临床效果。方法选择2011年2月~2014年2月本院收治的基底节血肿患者52例,采用改良软通道微创穿刺引流技术进行治疗,手术后7 d采用格拉斯哥昏迷量表(GCS)评估患者的意识水平,手术后14 d采用斯堪的纳维亚卒中量表(SSS)对神经功能进行评分。结果52例患者中,完全恢复26例,生活基本自理22例,中转开颅4例,无一例死亡。术后7 d GCS评分与治疗前比较,差异无统计学意义(P>0.05),术后14 d GCS评分与治疗前比较,差异有统计学意义(P0.05);after 14 days surgery,the difference was significant (P<0.05).The SSS scores of 7 days and 14 days after surgery both displayed statistical differences (P<0.05 or P<0.01). Conclusion Improved minimally invasive puncture drainage in the treatment of basal ganglia hemorrhage using soft drainage tube can obtain a great effect with easy performance,which is worthy of expansion in clinic.

  7. Dependence of an ion current on a working voltage for Hall thruster TAL-WSF/D-55. Simple theory and experiment

    Science.gov (United States)

    Shumilin, Nikolay; Shumilin, Vladimir; Shumilin, Alexander

    2014-10-01

    In paper the simple model for the definition of interrelation between integral characteristics of Hall thrusters with an anode layer is offered. Concrete calculations were made for one of most often used Hall thrusters - TAL-WSF/D-55. While analysing the received theoretical dependences an attempt of comparison with results of an experimental research of thruster TAL-WSF/D-55 was made. With this purpose experimental dependence of specific impulse of Hall thruster TAL-WSF/D-55 on working voltage in range from 150 up to 350 V resulted in was used. It appeared, that these data contain some serious mistake and there is no reference to original works in this paper. In present report this mistake is corrected using original works. It is shown, that the offered simple model gives results close to a reality both qualitatively and quantitatively.

  8. Voltage-gated lipid ion channels

    DEFF Research Database (Denmark)

    Blicher, Andreas; Heimburg, Thomas Rainer

    2013-01-01

    Synthetic lipid membranes can display channel-like ion conduction events even in the absence of proteins. We show here that these events are voltage-gated with a quadratic voltage dependence as expected from electrostatic theory of capacitors. To this end, we recorded channel traces and current...... histograms in patch-experiments on lipid membranes. We derived a theoretical current-voltage relationship for pores in lipid membranes that describes the experimental data very well when assuming an asymmetric membrane. We determined the equilibrium constant between closed and open state and the open...... probability as a function of voltage. The voltage-dependence of the lipid pores is found comparable to that of protein channels. Lifetime distributions of open and closed events indicate that the channel open distribution does not follow exponential statistics but rather power law behavior for long open times...

  9. Voltage verification unit

    Science.gov (United States)

    Martin, Edward J.

    2008-01-15

    A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

  10. 双套管冲洗引流联合蛋白胶封堵在肠外瘘的护理体会%Nursing Experience of Dual Flush Tube Drainage Combined with Fibrin Glue Plugging Enterocutaneous Fistula

    Institute of Scientific and Technical Information of China (English)

    郝玉英

    2014-01-01

    目的探讨肠外瘘患者应用双套管持续冲洗引流联合纤维蛋白胶封堵瘘管的护理特点。方法回顾性分析2010年1月至2013年1月我院收治的15例肠外瘘患者使用双套管持续冲洗引流联合纤维蛋白胶封堵瘘管的护理方法。结果通过有效的个体化阶段性和综合性护理,患者住院时间(20±4)d,保守治疗肠外瘘成功率93.3%。结论腹腔双套管持续冲洗引流联合纤维蛋白胶封堵肠外瘘成功率高,护理重点在于关注患者心理护理、双套管护理、瘘口周围皮肤护理。%Objective To investigate the application of dual flush tube drainage combined with fibrin glue in plugging en-terocutaneous fistula.Methods Retrospectivly analysis the nursing methods of dual flush tube drainage combined with fibrin glue plugging enterocutaneous fistula in 15 petients from January 2010 to January 2013 in our hospital.Results Through effective indi-vidual stages and comprehensive care, hospitalization time were (20±4)d,enterocutaneous fistula conservative treatment success rate of 93.3%.Conclusion Abdominal double cannula continuous irrigation and drainage combined with fibrin glue plugginh en-terocutaneous fistula is easily success,the nursing focus is pay attention to patients' psychological nursing、dual flush tube nursing snd the surrounding fistula skin care.

  11. Nocturnal drainage wind characteristics in two converging air sheds

    Energy Technology Data Exchange (ETDEWEB)

    Gedayloo, T.; Clements, W.E.; Barr, S.; Archuleta, J.A.

    1980-01-01

    During the short experimental period in the Grants Basin of Northeastern New Mexico a survey was conducted on the complex meteorology of this area. Emphasis was placed on the nocturnal drainage flow because of the potential hazards to the populated areas of Milan and Grants from the effluents of the uranium mining and milling operation in this area. This investigation has shown that the nocturnal drainage flow patterns agree with the winds predicted on the basis of the complex terrain of the area. Because of the surface cooling at night (over 25/sup 0/C during summer and about 20/sup 0/C during winter), air from elevated surrounding areas flows to the low lying regions consequently setting up a nocturnal drainage flow. This regime exists over 60% of the time during summer months and over 65% of the time during winter months with a depth generally less than 200 m. In the San Mateo air shed the drainage flow is east northeast, and in the Ambrosia Lake air shed it is from northwest. The confluence of these two air flows contributes mainly to the drainage flow through the channel formed by La Ja Mesa and Mesa Montanosa. The analysis of data collected by the recording Flats Station confirms the prediction that although the area south of the channel region broadens considerably causing a reduction in flow speed, contributions from the southside of La Jara Mesa and Mesa Montanosa partly compensate for this reduction. The position of this recording station is 15 to 20 km from the populated towns of Milan and Grants. A drainage flow speed of approximately 2.2 m s/sup -1/ and the duration of over 11 hours as recorded by this station indicates that air from the San Mateo and Ambrosia Lake regions may be transported southwards to these population centers during a nocturnal period. In order to test this prediction, a series of multi-atmospheric tracer experiments were conducted in the Grants Basin.

  12. Drainage area data for Alabama streams

    Science.gov (United States)

    Stallings, J.S.; Peirce, L.B.

    1957-01-01

    The drainage area of a river basin is an important parameter in many engineering equations used for hydrologic design. It is not a parameter, however, that always requires precise measurement. Factors in the hydrologic cycle such as rainfall, runoff, transpiration, and infiltration cannot be measured nearly as closely as drainage area. Largely for this reason, drainage areas are often measured to varying degrees of precision depending upon the immediate need, with little thought to some other use or some other user of the figure obtained. It can readily be appreciated that this practice, continued for long by many different agencies, will result in a heterogeneous collection of drainage area figures, often discordant and of an accuracy unknown to any but those who computed them. Figures of drainage area published by various Federal agencies are frequently discrepant or contradictory, giving rise to confusion in the use of drainage area data. Seeking to better this situation, the Federal Inter-Agency River Basin Committee (FIARBC) in November 1951 published its Bulletin No. 4, Inter-Agency Coordination of Drainage Area Data. That Bulletin recommended procedures to be followed by the interested Federal agencies “for coordinating drainage area data in the interest of promoting uniformity, reducing confusion and contradiction of published figures, and improving the ready availability of drainage area data pertaining to drainage basins of the United States and its possessions.”

  13. Exploring Three-Phase Systems and Synchronous Motors: A Low-Voltage and Low-Cost Experiment at the Sophomore Level

    Science.gov (United States)

    Schubert, T. F., Jr.; Jacobitz, F. G.; Kim, E. M.

    2011-01-01

    In order to meet changing curricular and societal needs, a three-phase system and synchronous motor laboratory experience for sophomore-level students in a wide variety of engineering majors was designed, implemented, and assessed. The experiment is unusual in its early placement in the curriculum, and in that it focuses primarily on basic…

  14. Piezoelectric Voltage Coupled Reentrant Cavity Resonator

    CERN Document Server

    Carvalho, Natalia C; Floch, Jean-Michel Le; Tobar, Michael Edmund

    2014-01-01

    A piezoelectric voltage coupled microwave reentrant cavity has been developed. The central cavity post is bonded to a piezoelectric actuator allowing the voltage control of small post displacements over a high dynamic range. We show that such a cavity can be implemented as a voltage tunable resonator, a transducer for exciting and measuring mechanical modes of the structure and a transducer for measuring comparative sensitivity of the piezoelectric material. Experiments were conducted at room and cryogenic temperatures with results verified using Finite Element software.

  15. Mine Drainage Generation and Control Options.

    Science.gov (United States)

    Wei, Xinchao; Rodak, Carolyn M; Zhang, Shicheng; Han, Yuexin; Wolfe, F Andrew

    2016-10-01

    This review provides a snapshot of papers published in 2015 relevant to the topic of mine drainage generation and control options. The review is broken into 3 sections: Generation, Prediction and Prevention, and Treatment Options. The first section, mine drainage generation, focuses on the characterization of mine drainage and the environmental impacts. As such, it is broken into three subsections focused on microbiological characterization, physiochemical characterization, and environmental impacts. The second section of the review is divided into two subsections focused on either the prediction or prevention of acid mine drainage. The final section focuses on treatment options for mine drainage and waste sludge. The third section contains subsections on passive treatment, biological treatment, physiochemical treatment, and a new subsection on beneficial uses for mine drainage and treatment wastes.

  16. [Simple cholecystectomy without drainage. A dilemma?].

    Science.gov (United States)

    Macellari, G; Baraldi, U; Giustina, A; David, P; Parigi, M; De Angelis, E

    1980-04-30

    A retrospective study was carried out to show the uselessness of the routine employment of the drainage after simple cholecystectomy. 1425 patients underwent cholecystectomy because for cholelithiasis; of these 164 (13%) were drained because of adhesions, concomitant pancreatitis, inadvertent damage, empiema, gangrena and perforation of the gallbladder. In no case of the 1261 patients without drainage it has been possible to demonstrate the presence of one of those complications for which the use of a drainage after simple cholecystectomy is commonly advised.

  17. Drainage basin delineations for selected USGS streamflow-gaging stations in Virginia (Drainage_Basin)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Drainage_Basin polygon feature class was created as a digital representation of drainage basins for more than 1,650 continuous-record streamflow-gaging stations,...

  18. High Voltage Distribution

    Science.gov (United States)

    Norbeck, Edwin; Miller, Michael; Onel, Yasar

    2010-11-01

    For detector arrays that require 5 to 10 kV at a few microamps each for hundreds of detectors, using hundreds of HV power supplies is unreasonable. Bundles of hundreds of HV cables take up space that should be filled with detectors. A typical HV module can supply 1 ma, enough current for hundreds of detectors. It is better to use a single HV module and distribute the current as needed. We show a circuit that, for each detector, measures the current, cuts off the voltage if the current exceeds a set maximum, and allows the HV to be turned on or off from a control computer. The entire array requires a single HV cable and 2 or 3 control lines. This design provides the same voltage to all of the detectors, the voltage set by the single HV module. Some additional circuitry would allow a computer controlled voltage drop between the HV and each individual detector.

  19. High voltage engineering fundamentals

    CERN Document Server

    Kuffel, E; Hammond, P

    1984-01-01

    Provides a comprehensive treatment of high voltage engineering fundamentals at the introductory and intermediate levels. It covers: techniques used for generation and measurement of high direct, alternating and surge voltages for general application in industrial testing and selected special examples found in basic research; analytical and numerical calculation of electrostatic fields in simple practical insulation system; basic ionisation and decay processes in gases and breakdown mechanisms of gaseous, liquid and solid dielectrics; partial discharges and modern discharge detectors; and over

  20. Percutaneous biliary drainage in acute suppurative cholangitis with biliary sepsis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Lyul; Cho, June Sik; Kwon, Soon Tae; Lee, Sang Jin; Rhee, Byung Chull [Chungnam National University College of Medicine, Daejeon (Korea, Republic of)

    1993-11-15

    Acute suppurative cholangitis is a severe inflammatory process of the bile duct occurred as result of partial or complete obstruction of the bile duct, and may manifest clinically severe form of disease, rapidly deteriorating to life-threatening condition. We analyzed emergency percutaneous transhepatic biliary drainage in 20 patients of acute suppurative cholangitis with biliary sepsis to evaluate the therapeutic effect and complication of the procedure. The underlying cause were 12 benign disease(stones) and eight malignant tumors and among eight malignant tumors, bile duct stones(n=4) and clonorchiasis(n=1) were combined. Percutaneous transhepatic biliary drainage was performed successfully in 17 of 20 patients resulting in improvement of general condition and failed in three patients. The procedure were preterminated due to the patient's condition in two and biliary-proto fistula was developed in one. After biliary decompression by percutaneous transhepatic biliary drainage, effective and successful elective surgery was performed in nine cases, which were seven biliary stones and two biliary cancer with stones. Our experience suggest that emergency percutaneous transhepatic biliary drainage is an initial and effective treatment of choice for acute suppurative cholangitis with sepsis and a safe alternative for nonsurgical treatment.

  1. Sulphates Removal from Acid Mine Drainage

    Science.gov (United States)

    Luptáková, Alena; Mačingová, Eva; Kotuličová, Ingrida; Rudzanová, Dominika

    2016-10-01

    Acid mine drainage (AMD) are a worldwide problem leading to ecological destruction in river basins and the contamination of water sources. AMD are characterized by low pH and high content of heavy metals and sulphates. In order to minimize negative impacts of AMD appropriate treatment techniques has to be chosen. Treatment processes are focused on neutralizing, stabilizing and removing pollutants. From this reason efficient and environmental friendly methods are needed to be developed in order to reduce heavy metals as well as sulphates. Various methods are used for remediation of acid mine drainage, but any of them have been applied under commercial-scale conditions. Their application depends on geochemical, technical, natural, financial, and other factors. The aim of the present work was to interpret the study of biological methods for sulphates removal from AMD out-flowing from the shaft Pech of the deposit Smolmk in Slovak Republic. In the experimental works AMD were used after removal of heavy metals by precipitation and sorption using the synthetic sorbent Slovakite. The base of the studied method for the sulphates elimination was the anaerobic bacterial sulphate reduction using sulphate-reducing bacteria (SRB) genera Desulfovibrio. SRB represent a group of bacteria that uses sulphates as a terminal electron acceptor for their metabolism. These bacteria realize the conversion of sulphate to hydrogen sulphide under anaerobic conditions. For the purposes of experiments a few variants of the selective medium DSM-63 culture media were used in term of the sulphates and sodium lactate contents in the selective medium as well as sulphates in the studied AMD.

  2. Low-voltage gyrotrons

    Science.gov (United States)

    Glyavin, M. Yu.; Zavolskiy, N. A.; Sedov, A. S.; Nusinovich, G. S.

    2013-03-01

    For a long time, the gyrotrons were primarily developed for electron cyclotron heating and current drive of plasmas in controlled fusion reactors where a multi-megawatt, quasi-continuous millimeter-wave power is required. In addition to this important application, there are other applications (and their number increases with time) which do not require a very high power level, but such issues as the ability to operate at low voltages and have compact devices are very important. For example, gyrotrons are of interest for a dynamic nuclear polarization, which improves the sensitivity of the nuclear magnetic resonance spectroscopy. In this paper, some issues important for operation of gyrotrons driven by low-voltage electron beams are analyzed. An emphasis is made on the efficiency of low-voltage gyrotron operation at the fundamental and higher cyclotron harmonics. These efficiencies calculated with the account for ohmic losses were, first, determined in the framework of the generalized gyrotron theory based on the cold-cavity approximation. Then, more accurate, self-consistent calculations for the fundamental and second harmonic low-voltage sub-THz gyrotron designs were carried out. Results of these calculations are presented and discussed. It is shown that operation of the fundamental and second harmonic gyrotrons with noticeable efficiencies is possible even at voltages as low as 5-10 kV. Even the third harmonic gyrotrons can operate at voltages about 15 kV, albeit with rather low efficiency (1%-2% in the submillimeter wavelength region).

  3. Subsurface drainage volume reduction with drainage water management: Case studies in Ohio, USA

    Science.gov (United States)

    One of the main contributors to poor water quality in the Mississippi River and aeral increase in the hypoxic zone in the Gulf of Mexico is intensive drainage of the cropland within the watershed. Controlled drainage has been demonstrated as an approach to curb totla drainage outflow and nutrient di...

  4. Simulation of the erosion and drainage development of Loess surface based on GIS

    Science.gov (United States)

    Wang, Chun; Tang, Guoan; Ge, Shanshan; Li, Zhanbin; Zhou, Jieyu

    2006-10-01

    The research probes into the temporal-spatial process of drainage development of Loess Plateau on the basis of a carefully designed experiment. In the experiment, the development of a simulated loess watershed is tested under the condition of lab-simulated rainfall. A close-range photogrammetry survey is employed to establish a series of high precision and resolution DEM (Digit Elevation Model) of the simulated loess surface. Based on the established DEM, the erosion loss, the slope distribution, the topographic index , the gully-brink, and the drainage networks are all derived and discussed through comparison analysis and experimental validation. All the efforts aim at revealing the process and mechanism of erosion and drainage development of loess surface .This study demonstrates: 1) the stimulation result can effectively reflect the truth if those experimental conditions, i.e. loess soil structure, simulated rainfall, are adjusted in accord with true situation; 2) the remarkable character of the erosion and drainage up-growth of loess surface include the drainage traced to the source, the increased of the drainage's density, the enlarged of gully, the durative variety of multiple terrain factor's mean value and its distribution, such as slope and topographic index; 3) The slope spectrum is the more felicitous terrain factor for depicting the erosion and drainage development of loess surface, including the rule of erosion and evolution process. It is the new way and mean for studying the loess physiognomy.

  5. Device for monitoring cell voltage

    Science.gov (United States)

    Doepke, Matthias [Garbsen, DE; Eisermann, Henning [Edermissen, DE

    2012-08-21

    A device for monitoring a rechargeable battery having a number of electrically connected cells includes at least one current interruption switch for interrupting current flowing through at least one associated cell and a plurality of monitoring units for detecting cell voltage. Each monitoring unit is associated with a single cell and includes a reference voltage unit for producing a defined reference threshold voltage and a voltage comparison unit for comparing the reference threshold voltage with a partial cell voltage of the associated cell. The reference voltage unit is electrically supplied from the cell voltage of the associated cell. The voltage comparison unit is coupled to the at least one current interruption switch for interrupting the current of at least the current flowing through the associated cell, with a defined minimum difference between the reference threshold voltage and the partial cell voltage.

  6. Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

    Science.gov (United States)

    Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

    2015-04-01

    resistances were tested, again to accommodate a large range of potential drainage flows rates. The experiment was continued until the Sorbicell's capacity was exhausted, which gave experimentation times from 6 to 34 days, while continuously changing the drainage flow rate to simulate field drainage conditions, and to test the range of the Flowcap. The laboratory testing yielded a very good linear correlation between drainage flow rates and Sorbicell sampling rates, giving r = 0.99 for both the Q25 and the Q256 Flowcap. The Sorbicells in this experiment were designed to measure NO3, but the Flowcap can be used with any Sorbicell and thus be used to measure any compound of interest. The Flowcap does not need housing, electricity, or maintenance and continuously register drainage volumes and contaminant loads for periods up to one month. This, in addition to the low cost of the monitoring system, enables large-scale monitoring of contaminant loads via tube drains, giving valuable data for the improvement of contaminant transport models. Further, these data will help select and evaluate the different mitigation option to improve water quality.

  7. High voltage pulse generator

    Science.gov (United States)

    Fasching, George E.

    1977-03-08

    An improved high-voltage pulse generator has been provided which is especially useful in ultrasonic testing of rock core samples. An N number of capacitors are charged in parallel to V volts and at the proper instance are coupled in series to produce a high-voltage pulse of N times V volts. Rapid switching of the capacitors from the paralleled charging configuration to the series discharging configuration is accomplished by using silicon-controlled rectifiers which are chain self-triggered following the initial triggering of a first one of the rectifiers connected between the first and second of the plurality of charging capacitors. A timing and triggering circuit is provided to properly synchronize triggering pulses to the first SCR at a time when the charging voltage is not being applied to the parallel-connected charging capacitors. Alternate circuits are provided for controlling the application of the charging voltage from a charging circuit to be applied to the parallel capacitors which provides a selection of at least two different intervals in which the charging voltage is turned "off" to allow the SCR's connecting the capacitors in series to turn "off" before recharging begins. The high-voltage pulse-generating circuit including the N capacitors and corresponding SCR's which connect the capacitors in series when triggered "on" further includes diodes and series-connected inductors between the parallel-connected charging capacitors which allow sufficiently fast charging of the capacitors for a high pulse repetition rate and yet allow considerable control of the decay time of the high-voltage pulses from the pulse-generating circuit.

  8. STDUY ON RETENTION AND DRAINAGE PROPERTIES OF THE HIGH SUBSTITUTED DEGREE CATIONIC STARCH

    Institute of Scientific and Technical Information of China (English)

    Qijie Chen; Fushan Chen; Gaosheng Wang; Huiren Hu

    2004-01-01

    This paper deals with the retention and drainage properties of the high substituted degree cationic starch (HCS) prepared by half-dry process. The experiments show that HCS has remarkable effects on filler retention and drainage in papermaking industry. With the degree of substitution (DS) of HCS increasing, the effects on filler retention and drainage increase. When the DS of HCS is 0.509 and the dosage is 0.08%, the freeness decreases about 12oSR and the filler retention is 79.82%.

  9. 24 CFR 3285.604 - Drainage system.

    Science.gov (United States)

    2010-04-01

    ... § 3285.604 Drainage system. (a) Crossovers. Multi-section homes with plumbing in more than one section require drainage system crossover connections to join all sections of the home. The crossover design requirements are located in, and must be designed in accordance with, § 3280.610 of this chapter. (b)...

  10. Agricultural drainage: Towards an integrated approach

    NARCIS (Netherlands)

    Abdeldayem, S.; Hoevenaars, J.; Mollinga, P.P.; Scheuman, W.; Slootweg, R.; Steenbergen, van F.

    2005-01-01

    Drainage needs to reclaim its rightful position as an indispensable element in the integrated management of land and water. An integrated approach to drainage can be developed by means of systematic mapping of the functions of natural resources systems (goods and services) and the values attributed

  11. Endoscopic ultrasound-guided drainage of pancreatic pseudocysts

    DEFF Research Database (Denmark)

    Saftoiu, Adrian; Vilmann, Andreas; Vilmann, Peter

    2015-01-01

    Pancreatic pseudocysts are fluid collections in the peripancreatic tissues associated with acute or chronic pancreatitis. Endoscopic ultrasound (EUS)-guided drainage has become an established indication, having better results as compared to percutaneous drainage, nonguided endoscopic drainage...

  12. Percutaneous transhepatic biliary drainage in an infant with obstructive jaundice caused by neuroblastoma.

    Science.gov (United States)

    Saettini, Francesco; Agazzi, Roberto; Giraldi, Eugenia; Foglia, Carlo; Cavalleri, Laura; Morali, Laura; Fasolini, Giorgio; Spotti, Angelica; Provenzi, Massimo

    2015-04-01

    Neuroblastoma presenting with obstructive jaundice is a rare event. Management of this condition includes surgery, chemotherapy, radiotherapy, temporary cholecystostomy tube, endoscopic retrograde cholangiopancreatography (ERCP), and internal biliary drainage (IBD). We herein describe our experience with one infant affected by neuroblastoma presenting with jaundice, who successfully underwent percutaneous transhepatic biliary drainage (PTBD). This report introduces PTBD as a viable treatment option for neuroblastoma and obstructive jaundice and provides a review of the pertinent literature.

  13. Voltage Regulators for Photovoltaic Systems

    Science.gov (United States)

    Delombard, R.

    1986-01-01

    Two simple circuits developed to provide voltage regulation for highvoltage (i.e., is greater than 75 volts) and low-voltage (i.e., is less than 36 volts) photovoltaic/battery power systems. Use of these circuits results in voltage regulator small, low-cost, and reliable, with very low power dissipation. Simple oscillator circuit controls photovoltaic-array current to regulate system voltage and control battery charging. Circuit senses battery (and system) voltage and adjusts array current to keep battery voltage from exceeding maximum voltage.

  14. Studying Voltage Transformer Ferroresonance

    Directory of Open Access Journals (Sweden)

    Hamid Radmanesh

    2012-09-01

    Full Text Available This study studies the effect of Circuit Breaker Shunt Resistance (CBSR, Metal Oxide Vaistor (MOV and Neutral earth Resistance (NR on the control of ferroresonance in the voltage transformer. It is expected that NR can controlled ferroresonance better than MOV and CBSR. Study has been done on a one phase voltage transformer rated 100 VA, 275 kV. The simulation results reveal that considering the CBSR and MOV exhibits a great mitigating effect on ferroresonance overvoltages, but these resistances cannot control these phenomena for all range of parameters. By applying NR to the system structure, ferroresonance has been controlled and its amplitude has been damped for all parameters values.

  15. 400 V Equipment and Experiments with Capacitor Var Compensation of Thyristor Series Voltage Regulation%400V晶闸管串联调压电容无功补偿装置及试验

    Institute of Scientific and Technical Information of China (English)

    王民慧; 李民族; 王武; 王世蓉

    2011-01-01

    The prototype of 400 V small capacity equipment is built and the tests are done on this equipment betore thyristor controlled reactance series compensation by adjustable coupling being put into practical application.The primary wiring device and the control and protection device with real function is developed.The steady-state parameters changes of corresponding voltage and current are tested during regulating process. The dynamic curves of thyristor current and compensation current are obtained when the device is switched on changing stage. Automatic voltage regulation and automatic power factor change experiments are done under large step changes.The test results show that this equipment can compensate reactive power in large scale and multi-stages with small impact current (rush current,surge current) when switched on. The time of changing stage is half cycle. It can automatically regulate voltage and power factor frequently.This equipment has full dynamic reactive power compensation function.%为使晶闸管串联调压电容无功补偿装置进入实用,对400V小容量装置样机进行了制作和试验.设计制作了一次接线装置和具有实际功能的控制保护装置;测试了升降级调节过程中有关电压、电流的稳态参数变化;测试了投入和换级操作过程中晶闸管电流和补偿电流的暂态波形;当负荷进行大幅度阶跃变化时,进行了自动调压和自动调节功率因数试验.测试和试验结果表明:装置能多级、大范围调节容性补偿无功;投入换级时冲击电流小,换级时间为0.5周波;能实现快速频繁的电压及功率因数等多种自动调节功能,完全具有动态无功补偿装置的技术性能.

  16. Simulated hydrodynamics study on rationality of placement of pancreatic drainage after pancreaticoduodenectomy

    Directory of Open Access Journals (Sweden)

    Kai JIANG

    2014-03-01

    Full Text Available Objective  To explore a rational method of placing appropriate pancreatic drainage after pancreaticoduodenectomy, and evaluate its safety and feasibility. Methods  Classic Bernoulli's flowing mechanics energy equation (Bernoulli's equation was used to calculate the dynamics of pancreatic juice flowing inside of the drainage tube. With given constant flowing velocity and density of pancreatic juice, four related factors on ΔP(pressure difference between entrance and exit planes of drainage tube were investigated viarehearsing the formula. Effects on draining velocity by diameter and length of the tube were further verified by use of self-made pancreas drainage simulator, as well as the impact of liquid level difference on ΔP. Results  Data obtained from calculation elucidated that the rank of 4 related factors was as follows: inner diameter﹥liquid level difference﹥liquid viscosity﹥tube length. The experiment also verified that the influence of draining velocity depended more on diameter rather than length. Liquid level difference was identified as major independent impact factor on ΔP. Conclusions  Tube calibre ranging 1.5-2.0mm to allow a continuity of liquid flow is an essential factor to promise a fluent drainage. A 1.4m-length drainage tube is recommended for external draining, however, intraintestinal drainage of the pancreatic duct may be the best option. DOI: 10.11855/j.issn.0577-7402.2014.03.03

  17. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean.

    Science.gov (United States)

    Glasser, Neil F; Jansson, Krister N; Duller, Geoffrey A T; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-02-12

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface "hosing" to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate.

  18. HIGH VOLTAGE SAFETY MANAGEMENT SYSTEM OF ELECTRIC VEHICLE

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to improve the drivability and energy efficiency of electric vehicle (EV), more and more batteries are connected in series with high voltage which makes it necessary to monitor the electric parameters of high voltage system (HVS) to ensure the high voltage safety. A high voltage safety management system is developed to solve this critical issue. Several key electric parameters including pre-charge, contact resistance, insulation resistance and remaining capacity are monitored and analyzed based on the presented equivalent models. An electronic unit called high voltage safety controller is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated and the on-line electric parameters monitor strategy is discussed. The real vehicle experiment results indicate that the high voltage safety management system designed is suitable for EV application.

  19. The Geochemistry of Acid Mine Drainage

    Science.gov (United States)

    Blowes, D. W.; Ptacek, C. J.; Jambor, J. L.; Weisener, C. G.

    2003-12-01

    Mine wastes are the largest volume of materials handled in the world (ICOLD, 1996). The generation of acidic drainage and the release of water containing high concentrations of dissolved metals from these wastes is an environmental problem of international scale. Acidic drainage is caused by the oxidation of sulfide minerals exposed to atmospheric oxygen. Although acid drainage is commonly associated with the extraction and processing of sulfide-bearing metalliferous ore deposits and sulfide-rich coal, acidic drainage can occur wherever sulfide minerals are excavated and exposed to atmospheric oxygen. Engineering projects, including road construction, airport development, and foundation excavation are examples of civil projects that have resulted in the generation of acidic drainage. On United States Forest Service Lands there are (2-5)×104 mines releasing acidic drainage (USDA, 1993). Kleinmann et al. (1991) estimated that more than 6,400 km of rivers and streams in the eastern United States have been adversely affected by mine-drainage water. About (0.8-1.6)×104 km of streams have been affected by metal mining in the western United States. The annual worldwide production of mine wastes exceeded 4.5 Gt in 1982 (ICOLD, 1996). Estimated costs for remediating mine wastes internationally total in the tens of billions of dollars ( Feasby et al.,1991).

  20. Drenagem anômala total das veias pulmonares: 29 anos de experiência em uma única instituição Drenaje anómalo total de las venas pulmonares: 29 años de experiencia en una única institución Total anomalous pulmonary venous drainage: 29 years of experience in a single institution

    Directory of Open Access Journals (Sweden)

    Maira L. Basso

    2010-05-01

    experiencia de 29 años de un único servicio, se probaron posibles variables relacionadas al óbito hospitalario. MÉTODOS: Análisis retrospectivo de 123 pacientes consecutivos operados con el diagnóstico de DATVP entre enero de 1979 y marzo de 2008. Se incluyeron solamente a pacientes con DATVP aislada, excluidas las asociaciones complejas. Las variables se probaron para la identificación de la influencia sobre los óbitos y de la interferencia de la evolución temporal. RESULTADOS: Las medianas de peso y edad fueron de 4,1 kg y 120 días, respectivamente. El subtipo anatómico supracardiaco fue el más prevalente en todo el período analizado. Obstrucción al drenaje estuvo presente en el 30% de los casos, con el subtipo infracardiaco siendo el más asociado. La tasa de mortalidad general fue del 27%, y llegó acero en los últimos cinco años. Tanto en el análisis univariado como en la multivariada, la presencia de obstrucción al flujo venoso pulmonar fue la única variable positivamente asociada a los óbitos (p = 0,005, independientemente de la evolución temporal. La mortalidad entre estos casos fue del 44%. CONCLUSIÓN: Tras tres décadas de evolución, se puede observar mejora en la mortalidad precoz del drenaje anómalo total de las venas pulmonares en nuestro servicio, que actualmente presenta niveles consistentes con la literatura. La obstrucción al drenaje pulmonar sigue siendo factor de malo pronóstico en nuestro medio.BACKGROUND: Total anomalous pulmonary venous drainage (TAPVD is a rare disease, with an approximate incidence of 0.058 to 0.083:1,000 live births. It has a mortality rate of around 80% to 90% in the first year, if not treated early. OBJECTIVE: Using the 29-year experience of a single center, possible variables related to hospital death were tested. METHODS: Retrospective analysis of 123 consecutive patients with a diagnosis of TAPVD that underwent surgical treatment between January 1979 and March 2008. Only patients with isolated TAPVD were

  1. VOLTAGE REGULATORS ASYNCHRONOUS GENERATORS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-06-01

    Full Text Available A promising is currently the use of asynchronous generators with capacitive excitation as a source of electricity in stand-alone power systems. Drive asynchronous generators may exercise as a thermal engine and wind wheel wind power plant or turbines of small hydropower plants. The article discusses the structural and schematics of voltage stabilizers and frequency of asynchronous generators with improved operational and technical specifications. Technical novelty of design solutions of the magnetic system and stabilizers asynchronous generator of electricity parameters confirmed by the patents for the invention of the Russian Federation. The proposed technical solution voltage stabilizer asynchronous generators, can reduce the weight of the block capacitors excitation and reactive power compensation, as well as to simplify the control system power circuit which has less power electronic devices. For wind power plants it is an important issue not only to stabilize the voltage of the generator, but also the frequency of the current. Recommend functionality stabilizer schemes parameters of electric power made for direct frequency converters with artificial and natural switching power electronic devices. It is also proposed as part of stabilization systems use single-phase voltage, three-phase transformers with rotating magnetic field, reduce the level of electromagnetic interference generated by power electronic devices for switching, enhance the efficiency and reliability of the stabilizer.

  2. Geomagnetism and Induced Voltage

    Science.gov (United States)

    Abdul-Razzaq, W.; Biller, R. D.

    2010-01-01

    Introductory physics laboratories have seen an influx of "conceptual integrated science" over time in their classrooms with elements of other sciences such as chemistry, biology, Earth science, and astronomy. We describe a laboratory to introduce this development, as it attracts attention to the voltage induced in the human brain as it…

  3. Experimental validation of prototype high voltage bushing

    Science.gov (United States)

    Shah, Sejal; Tyagi, H.; Sharma, D.; Parmar, D.; M. N., Vishnudev; Joshi, K.; Patel, K.; Yadav, A.; Patel, R.; Bandyopadhyay, M.; Rotti, C.; Chakraborty, A.

    2017-08-01

    Prototype High voltage bushing (PHVB) is a scaled down configuration of DNB High Voltage Bushing (HVB) of ITER. It is designed for operation at 50 kV DC to ensure operational performance and thereby confirming the design configuration of DNB HVB. Two concentric insulators viz. Ceramic and Fiber reinforced polymer (FRP) rings are used as double layered vacuum boundary for 50 kV isolation between grounded and high voltage flanges. Stress shields are designed for smooth electric field distribution. During ceramic to Kovar brazing, spilling cannot be controlled which may lead to high localized electrostatic stress. To understand spilling phenomenon and precise stress calculation, quantitative analysis was performed using Scanning Electron Microscopy (SEM) of brazed sample and similar configuration modeled while performing the Finite Element (FE) analysis. FE analysis of PHVB is performed to find out electrical stresses on different areas of PHVB and are maintained similar to DNB HV Bushing. With this configuration, the experiment is performed considering ITER like vacuum and electrical parameters. Initial HV test is performed by temporary vacuum sealing arrangements using gaskets/O-rings at both ends in order to achieve desired vacuum and keep the system maintainable. During validation test, 50 kV voltage withstand is performed for one hour. Voltage withstand test for 60 kV DC (20% higher rated voltage) have also been performed without any breakdown. Successful operation of PHVB confirms the design of DNB HV Bushing. In this paper, configuration of PHVB with experimental validation data is presented.

  4. Gravity Drainage Kinetics of Papermaking Fibrous Suspensions

    Directory of Open Access Journals (Sweden)

    Przybysz Piotr

    2014-12-01

    Full Text Available The study analyses application possibilities of filtration and thickening models in evaluation of papermaking suspension drainage rate. The authors proposed their own method to estimate the drainage rate on the basis of an existing Ergun capillary model of liquid flow through a granular material. The proposed model was less sensitive to porosity changes than the Ergun model. An empirical verification proved robustness of the proposed approach. Taking into account discrepancies in the published data concerning how the drainage velocity of papermaking suspension is defined, this study examines which of the commonly applied models matches experimental results the best.

  5. Drainage filter technologies to mitigate site-specific phosphorus losses in agricultural drainage discharge

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Canga, Eriona;

    Losses of phosphorus (P) in drainage waters contribute an estimated 33% to the total agricultural P load in Denmark. Mitigating agricultural P losses is challenging, as critical P losses comprise only a very small fraction of actual soil P contents and are not directly related to fertilizer P input...... in drainage. The Danish “SUPREME-TECH” project (2010-2016) (www.supreme-tech.dk) aims at providing the scientific basis for developing cost-effective filter technologies for P in agricultural drainage waters. The project studies different approaches of implementing filter technologies including drainage well...... the occurrence of surface-induced precipitation processes. The P-retention efficiency of granular drainage filters and constructed wetlands was compared for treating drainage water, and a subcatchment analysis illustrated the potential of implementing such measures....

  6. Effect of P-Reactive Drainage Aggregates on Green Roof Runoff Quality

    Directory of Open Access Journals (Sweden)

    Agnieszka Karczmarczyk

    2014-08-01

    Full Text Available The main hypothesis of the presented study is that the negative effect of phosphorus leaching from a green roof substrate can be reduced by including P-reactive material in a drainage layer. In this work, different aggregates (Pollytag®, lightweight expanded clay aggregates, chalcedony, serpentynite and crushed autoclaved aerated concrete to be used as the green roof drainage layer are described. Physical parameters, e.g., granulometric composition, water absorption, bulk density and porosity are assessed. A phosphorus sorption isotherm and a kinetic test were performed. Physical and chemical characteristics of the materials were used as a base for choosing the best media for the drainage layer. The P-removal efficiency of crushed autoclaved aerated concrete was confirmed in a column experiment. Adding the implementation of the P-reactive material in a drainage layer during construction can reduce the negative effect of substrate on green roof runoff quality.

  7. Fractal Analysis of Drainage Basins on Mars

    Science.gov (United States)

    Stepinski, T. F.; Marinova, M. M.; McGovern, P. J.; Clifford, S. M.

    2002-01-01

    We used statistical properties of drainage networks on Mars as a measure of martian landscape morphology and an indicator of landscape evolution processes. We utilize the Mars Orbiter Laser Altimeter (MOLA) data to construct digital elevation maps (DEMs) of several, mostly ancient, martian terrains. Drainage basins and channel networks are computationally extracted from DEMs and their structures are analyzed and compared to drainage networks extracted from terrestrial and lunar DEMs. We show that martian networks are self-affine statistical fractals with planar properties similar to terrestrial networks, but vertical properties similar to lunar networks. The uniformity of martian drainage density is between those for terrestrial and lunar landscapes. Our results are consistent with the roughening of ancient martian terrains by combination of rainfall-fed erosion and impacts, although roughening by other fluvial processes cannot be excluded. The notion of sustained rainfall in recent Mars history is inconsistent with our findings.

  8. Results of percutaneous transhepatic cholangiography drainages (PTCD)

    Energy Technology Data Exchange (ETDEWEB)

    Schoenemann, J.; Willems, M.; Wolf, G.; Fromme, M.

    1987-12-01

    From September 1980 to December 1986, 72 percutaneous transhepatic cholangiography drainages (PTCD) were performed in 64 patients (58 palliative in malignant obstructions, 14 temporary). The median duration of drainage was 26.8 days (2-183 days). The median survival time in 37 patients with palliative tumour drainage was 55.3 days (7-473 days). 9/37 patients survived longer than 3 months (max. 15.5 months). Complications occurred in 29.5% (10.3% severe). 3/64 patients (4.7%) died. Patients with palliative transpapillary drainages (23), especially with endoprostheses (14), survived longer, and the complication rate was lower. Therefore, we prefer the endoscopic transpapillary approach. PTCD patients must be selected carefully.

  9. Fractal Analysis of Drainage Basins on Mars

    Science.gov (United States)

    Stepinski, T. F.; Marinova, M. M.; McGovern, P. J.; Clifford, S. M.

    2002-01-01

    We used statistical properties of drainage networks on Mars as a measure of martian landscape morphology and an indicator of landscape evolution processes. We utilize the Mars Orbiter Laser Altimeter (MOLA) data to construct digital elevation maps (DEMs) of several, mostly ancient, martian terrains. Drainage basins and channel networks are computationally extracted from DEMs and their structures are analyzed and compared to drainage networks extracted from terrestrial and lunar DEMs. We show that martian networks are self-affine statistical fractals with planar properties similar to terrestrial networks, but vertical properties similar to lunar networks. The uniformity of martian drainage density is between those for terrestrial and lunar landscapes. Our results are consistent with the roughening of ancient martian terrains by combination of rainfall-fed erosion and impacts, although roughening by other fluvial processes cannot be excluded. The notion of sustained rainfall in recent Mars history is inconsistent with our findings.

  10. Voltage Sags Ride-Through of Motion Sensorless Controlled PMSG for Wind Turbines

    DEFF Research Database (Denmark)

    Fatu, Marius; Lascu, Cristian; Andreescu, Gheorghe-Daniel;

    2007-01-01

    is used to robustly estimate the grid voltage positivesequence for control in the case of asymmetric voltages. The paper investigates the ride-through performance of this system during asymmetric power grid voltage sags. Design details for various parts of the control system are presented, together...... with experimental results for single-, two-, and three-phase voltage source sags. Smooth transition through asymmetric voltage sags is demonstrated by all experiments....

  11. THE ENVIRONMENTAL IMPACT OF ACID MINE DRAINAGE

    OpenAIRE

    GRAY, NICHOLAS FREDERICK; Sullivan, Monica

    2017-01-01

    This review examine the action of acid mine drainage (AMD), which is a multifactor pollutant, on surface waters. It affects aquatic ecosystems via a number of direct and indirect pathways. Major impact areas are coastal waters, rivers, lakes and estuaries, with AMD affecting ecosystems in different ways. Ground waters can also be severely impacted. Due to its complexity, the impact of AMD is particularly difficult to quantify and predict in lotic systems. Acid mine drainage pollut...

  12. Deployment of low-voltage regulator considering existing voltage control in medium-voltage distribution systems

    Directory of Open Access Journals (Sweden)

    Hiroshi Kikusato

    2016-01-01

    Full Text Available Many photovoltaic (PV systems have been installed in distribution systems. This installation complicates the maintenance of all voltages within the appropriate range in all low-voltage distribution systems (LVDSs because the trends in voltage fluctuation differ in each LVDS. The installation of a low-voltage regulator (LVR that can accordingly control the voltage in each LVDS has been studied as a solution to this problem. Voltage control in a medium-voltage distribution system must be considered to study the deployment of LVRs. In this study, we installed LVRs in the LVDSs in which the existing voltage-control scheme cannot prevent voltage deviation and performed a numerical simulation by using a distribution system model with PV to evaluate the deployment of the LVRs.

  13. Percutaneous drainage of pelvic fluid collection

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Young; Sohn, Cheol Ho [School of Medicine Keimyung University, Daegu (Korea, Republic of)

    1995-10-15

    To evaluate safe access route and success rate of percutaneous drainage of pelvic fluid collection. The 35 percutaneous drainages of pelvic fluid collection under the CT and fluorosocpic guidance were done in 32 patients. The anterior transabdominal approach was done in 20 patients, while the nine patients used the transgluteal approach through greater sciatic foramen. Three patients, who had septated or noncommunicating abscesses, underwent drainage using both approaches. The catheter was removed when the patient's symptom and laboratory data were improved or the amount of drainage and the size of fluid collection were markedly reduced. Success, partial success and failure were classified. The causes of fluid collection were complication of intraabdominal operation in 27 patient. The diagnosis after drainage included abscess (21), loculated ascites (6), and hematoma (4). The 27 cases (30 procedure) were treated successfully and the mean duration of catheter insertion was 10 days. The partial successes were two cases (2 procedures), which had palliative purpose. Three cases (3 procedures) were failed, which were multiple loculated ascites of pancreatic origin (2) and recurrent abscess (1). The significant complication during the procedure or drainage was not noted.

  14. Analyzing of Dynamic Voltage Restorer in Series Compensation Voltage

    Directory of Open Access Journals (Sweden)

    Naser Parhizgar

    2012-02-01

    Full Text Available The Dynamic Voltage Restorer (DVR is a series-connected compensator to generate a controllable voltage to against the short-term voltage disturbances. The technique of DVR is an effective and cost competitive approach to improve voltage quality at the load side. This study presents a single-phase and threephase DVR system with reduced switch-count topology to protect the sensitive load against abnormal voltage conditions. Most basic function, the DVR configuration consist of a two level Voltage Source Converter (VSC, a dc energy storage device, a coupling transformer Connected in shunt with the ac system This study presents the application of Dynamic Voltage Restorer (DVR on power distribution systems for mitigation of voltage sag at critical loads. DVR is one of the compensating types of custom power devices. The DVR, which is based on forced-commutated Voltage Source Converter (VSC has been proved suitable for the task of compensating voltage sags/swells. Simulation results are presented to illustrate and understand the performances of DVR in supporting load voltages under voltage sags/swells conditions.

  15. High Voltage Charge Pump

    KAUST Repository

    Emira, Ahmed A.

    2014-10-09

    Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

  16. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  17. 46 CFR 171.155 - Drainage of an open boat.

    Science.gov (United States)

    2010-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat. The deck within the hull of an open boat must drain to the bilge. Overboard drainage of the deck is not... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of an open boat. 171.155 Section 171.155...

  18. High-voltage test and measuring techniques

    CERN Document Server

    Hauschild, Wolfgang

    2014-01-01

    It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  19. [The value of wound drainage with or without suction].

    Science.gov (United States)

    Schmidt, J; Hasselbach, A; Schnorr, W; Baranek, T; Letsch, R

    2005-11-01

    Even though the discussion for desisting from wound drainage has arisen, this is not reflected in the reality of surgical treatment. In more than 90% of all procedures wound drainage is used. It remains to be proven whether suction drainage actually is superior to gravity drainage in everyday use. In a random study with 200 patients it was proven that suction drainage shows no significant advantage in liquid quantum, haematoma and the frequency of complications. We conclude that the economically favourable gravity drainage can replace the more expensive suction drainage in most cases.

  20. Failures and complications of thoracic drainage

    Directory of Open Access Journals (Sweden)

    Đorđević Ivana

    2006-01-01

    Full Text Available Background/Aim. Thoracic drainage is a surgical procedure for introducing a drain into the pleural space to drain its contents. Using this method, the pleura is discharged and set to the physiological state which enables the reexpansion of the lungs. The aim of the study was to prove that the use of modern principles and protocols of thoracic drainage significantly reduces the occurrence of failures and complications, rendering the treatment more efficient. Methods. The study included 967 patients treated by thoracic drainage within the period from January 1, 1989 to June 1, 2000. The studied patients were divided into 2 groups: group A of 463 patients treated in the period from January 1, 1989 to December 31, 1994 in whom 386 pleural drainage (83.36% were performed, and group B of 602 patients treated form January 1, 1995 to June 1, 2000 in whom 581 pleural drainage (96.51% were performed. The patients of the group A were drained using the classical standards of thoracic drainage by the general surgeons. The patients of the group B, however, were drained using the modern standards of thoracic drainage by the thoracic surgeons, and the general surgeons trained for this kind of the surgery. Results. The study showed that better results were achieved in the treatment of the patients from the group B. The total incidence of the failures and complications of thoracic drainage decreased from 36.52% (group A to 12.73% (group B. The mean length of hospitalization of the patients without complications in the group A was 19.5 days versus 10 days in the group B. The mean length of the treatment of the patients with failures and complications of the drainage in the group A was 33.5 days versus 17.5 days in the group B. Conclusion. The shorter length of hospitalization and the lower morbidity of the studied patients were considered to be the result of the correct treatment using modern principles of thoracic drainage, a suitable surgical technique, and a

  1. 骨科创伤及感染创面应用负压封闭引流(VSD)治疗的护理体会%Orthopaedic Trauma and Infection Wound Application Negative Pressure Closed Drainage (VSD) Treatment of Nursing Experience

    Institute of Scientific and Technical Information of China (English)

    李建莉

    2012-01-01

      Objective to explore in the treatment of Vsd orthopaedic trauma and infection wound application effect and nursing experience. Methods the treatment of orthopaedic trauma and infection Vsd wound 68 cases. Results 68 cases of pa-tients cured by the Vsd after treatment,50 cases wound granuloma growth,fresh blood circulation is good. Bacterial culture were all negative. line free skin graft or direct suture after wound repair. 18 routine multiple drainage,flap to repair wounds af-ter success. Conclusion the treatment of Vsd orthopaedic trauma and infection wound can reduce the number of dressing,and effectively avoid the cross infection. nursing key is to keep the negative pressure drainage unobstructed and strengthen nutrition.%  目的探讨 Vsd 在治疗骨科创伤及感染创面的应用效果及护理体会.方法采用 Vsd 治疗骨科创伤及感染创面68例.结果68例患者经 Vsd 治疗后,50例创面肉芽肿生长,新鲜血液循环良好.细菌培养均阴性.行游离植皮或直接缝合后创面修复.18例行多次引流,皮瓣转移后创面修复成功.结论 Vsd 治疗骨科创伤及感染创面可减少换药次数,有效地避免了交叉感染.护理重点是保持负压引流通畅和加强营养.

  2. Experiment Study on Influence of Vacuum Sealing Drainage on Compression Bandage of Full-thickness Skin Grafting%负压封闭引流装置用于全厚皮移植术后加压固定

    Institute of Scientific and Technical Information of China (English)

    罗江蓉; 刘勇; 岑瑛

    2011-01-01

    Objective To explore the influence of vacuum sealing drainage (VSD) on compression bandage of full-thickness skin grafting. Methods A model of full-thickness skin grafting in 2 operation zones was established in the two sides of spinal column of 24 New Zealand white rabbits. The wounds were deal with by VSD (group A) and conventional suture and compression bandage (group B) randomly. About 3, 5, and 7 days after operation, the assessment of the center and edge area (suture area) of skin grafting was performed by a single observer blinded to the randomization. The survival rate was calculated. Samples were selected from skin grafting and observed under a light microscope after HE staining. The expression of vascular endothelial growth factor (VEGF) was detected by immunohistochemistry method. Results The assessment of the edge area of skin grafting in group A was significantly better than that in group B (P0. 05). HE staining showed that in the edge area of skin grafting, the cell layer and structure were better in group A than that in group B, the difference in the center area was not significant (P>0. 05). Immunohistochemistry method showed that in the edge area of skin grafting, integrated optical density of VEGF was significantly higher in group A than in group B (P0. 05). Conclusions VSD utilized on compression bandage of full-thickness skin grafting can significantly improve the qualitative appearance of grafting, promote wound healing and vascularization. VSD may possibly reduce scar hyperplasia.%目的 探讨封闭负压引流(vacuum sealing drainage,VSD)装置用于全厚皮移植术后加压固定对全厚皮片移植成活的影响.方法 新西兰大白兔24只,在脊柱两侧2个术区建立全厚皮片移植模型.每只兔2个术区分别采用VSD(A组)、传统缝合打包加压包扎(B组),做自身对照.第3、5、7天各随机处死8只兔,观察皮片成活情况,做移植皮片中央及边缘(指打包固定的缝

  3. Mitigation of Voltage Sags in CIGRE Low Voltage Distribution Network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Mahat, Pukar;

    2013-01-01

    problems in the distribution system. The voltage problems dealt with in this paper are to show how to mitigate voltage sags in the CIGRE Low Voltage (LV) test network and networks like this. The voltage sags, for the tested cases in the CIGRE LV test network are mainly due to three phase faults....... The compensation of voltage sags in the different parts of CIGRE distribution network is done by using the four STATCOM compensators already existing in the test grid. The simulations are carried out in DIgSILENT power factory software version 15.0....

  4. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    . An adaptive dynamic model has been developed to determine composite voltage dependency of an aggregated load on feeder level. Following the demand dispatch or control signal, optimum voltage setting at the LV substation is determined based on the voltage dependency of the load. Furthermore, a new technique...

  5. Charge-pump voltage converter

    Science.gov (United States)

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  6. Dynamic Performance of Grid Converters using Adaptive DC Voltage Control

    DEFF Research Database (Denmark)

    Trintis, Ionut; Sun, Bo; Guerrero, Josep M.;

    2014-01-01

    This paper investigates a controller that ensures minimum operating dc-link voltage of a back-to-back converter system. The dc-link voltage adapts its reference based on the system state, reference given by an outer loop to the dc-link voltage controller. The operating dc-link voltage should...... be kept as low as possible to increase the power conversion efficiency and increase the reliability of converters. The dynamic performance of the proposed controller is investigated by simulations and experiments....

  7. Transient voltage sharing in series-coupled high voltage switches

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1992-07-01

    Full Text Available For switching voltages in excess of the maximum blocking voltage of a switching element (for example, thyristor, MOSFET or bipolar transistor such elements are often coupled in series - and additional circuitry has to be provided to ensure equal voltage sharing. Between each such series element and system ground there is a certain parasitic capacitance that may draw a significant current during high-speed voltage transients. The "open" switch is modelled as a ladder network. Analy­sis reveals an exponential progression in the distribution of the applied voltage across the elements. Overstressing thus oc­curs in some of the elements at levels of the total voltage that are significantly below the design value. This difficulty is overcome by grading the voltage sharing circuitry, coupled in parallel with each element, in a prescribed manner, as set out here.

  8. Irrigation ponds:Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    BROWN; Larry

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  9. Irrigation ponds: Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    DONG Bin; MAO Zhi; BROWN Larry; CHEN XiuHong; PENG LiYuan; WANG JianZhang

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and un-recycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China.With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious.Traditional ir-rigation and drainage systems only focus on issues concerning water quantity, i.e.the capacity of irri-gation in drought and drainage in waterlogging period, yet have no requirement on water quality im-provement, how to clean the water quality of farmland drainage through remodeling the existing irriga-tion and drainage systems has a very important realistic meaning.Pond is an important irrigation facil-ity in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use.Such water storage features of pond provide the possibility and potential capacity for drainage water treat-ment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system.To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site.The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water.Other issues, e.g.how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  10. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    Directory of Open Access Journals (Sweden)

    Yanfei Kou

    2016-01-01

    Full Text Available Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve is proposed in this paper. The mathematic model of water hammer fluctuations is established based on the characteristic line method. Then, boundary conditions of water hammer controlling for mine drainage system are determined and its simplex model is established. The optimization adjustment strategy is solved from the mathematic model of multistage valve-closing. Taking a mine drainage system as an example, compared results between simulations and experiments show that the proposed method and the optimized valve-closing strategy are effective.

  11. Planar LTCC transformers for high voltage flyback converters.

    Energy Technology Data Exchange (ETDEWEB)

    Schofield, Daryl (NASCENT Technology Inc. , Watertown, SD); Schare, Joshua M.; Glass, Sarah Jill; Roesler, Alexander William; Ewsuk, Kevin Gregory; Slama, George (NASCENT Technology Inc. , Watertown, SD); Abel, Dave (NASCENT Technology Inc. , Watertown, SD)

    2007-06-01

    This paper discusses the design and use of low-temperature (850 C to 950 C) co-fired ceramic (LTCC) planar magnetic flyback transformers for applications that require conversion of a low voltage to high voltage (> 100V) with significant volumetric constraints. Measured performance and modeling results for multiple designs showed that the LTCC flyback transformer design and construction imposes serious limitations on the achievable coupling and significantly impacts the transformer performance and output voltage. This paper discusses the impact of various design factors that can provide improved performance by increasing transformer coupling and output voltage. The experiments performed on prototype units demonstrated LTCC transformer designs capable of greater than 2 kV output. Finally, the work investigated the effect of the LTCC microstructure on transformer insulation. Although this paper focuses on generating voltages in the kV range, the experimental characterization and discussion presented in this work applies to designs requiring lower voltage.

  12. Extensive experimental investigation of the effect of drainage height and solvent type on the stabilized drainage rate in vapour extraction (VAPEX process

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammadpoor

    2015-09-01

    Full Text Available The low cost of the injected solvent, which can be also recovered and recycled, and the applicability of VAPEX technique in thin reservoirs are among the main advantages of VAPEX process compared to thermal heavy oil recovery techniques. In this research, an extensive experimental investigation is carried out to first evaluate the technical feasibility of utilization of various solvents for VAPEX process. Then the effect of drainage height on the stabilized drainage rate in VAPEX process was studied by conducting series of experiments in two large-scale 2D VAPEX models of 24.5 cm and 47.5 cm heights. Both models were packed with low permeability Ottawa sand (#530 and saturated with a heavy oil sample from Saskatchewan heavy oil reservoirs with viscosity of 5650 mPa s. Propane, butane, methane, carbon dioxide, propane/carbon dioxide (70%/30% and propane/methane (70%/30% were considered as respective solvents for the experiments, and a total of twelve VAPEX tests were carried out. Moreover, separate experiments were carried out at the end of each VAPEX experiment to measure the asphaltene precipitation at various locations of the VAPEX models. It was found that injecting propane would result in the highest drainage rate and oil recovery factor. Further analysis of results showed stabilized drainage rate significantly increased in the larger physical model.

  13. Maximum permissible voltage of YBCO coated conductors

    Science.gov (United States)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z.; Hong, Z.; Wang, D.; Zhou, H.; Shen, X.; Shen, C.

    2014-06-01

    Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (Ic) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the Ic degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  14. Location of Agricultural Drainage Pipes and Assessment of Agricultural Drainage Pipe Conditions Using Ground Penetrating Radar

    Science.gov (United States)

    Methods are needed to not only locate buried agricultural drainage pipe, but to also determine if the pipes are functioning properly with respect to water delivery. The primary focus of this research project was to confirm the ability of ground penetrating radar (GPR) to locate buried drainage pipe ...

  15. Field studies of transport and dispersion of atmospheric tracers in nocturnal drainage flows

    Energy Technology Data Exchange (ETDEWEB)

    Gudiksen, P.H.; Ferber, G.J.; Fowler, M.M.; Eberhard, W.L.; Fosberg, M.A.; Knuth, W.R.

    1984-01-01

    A series of tracer experiments were carried out as part of the Atmospheric Studies in Complex Terrain (ASCOT) program to evaluate pollutant transport and dispersion characteristics of nocturnal drainage flows within a valley in northern California. The results indicate that the degree of interaction of the drainage flows with the larger scale regional flows are strongly dependent on how well the shallow drainage flows are shielded by the surrounding topography from the external environment. For the valley under study, the drainage flows from about mid-slope elevations and below were generally decoupled from the externally generated flows; as evidenced by the similarity of the surface tracer distribution produced during widely varying regional flow conditions. However, tracers released immediately above the drainage flows near the ridge top did reveal considerable mixing between the transition layer flows and the underlying surface drainage flows. Likewise, the transport and dispersion of the tracers at elevated heights within the valley basin were extremely dependent on the influences of the regional scale flows on the valley circulation. The dispersion rates associated with the transition layer flows were dependent on topographic constraints but were appreciably higher than those reported for homogeneous flat terrain situations.

  16. Ultrasound-guided endocavitary drainage of pelvic abscesses: Technique, results and complications

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, R.S.; McGrath, F P.; Haslam, P.J.; Varghese, J.C.; Lee, M.J

    2003-01-01

    AIM: To evaluate the experience in our institution with ultrasound-guided transrectal and transvaginal (endocavitary) drainage of pelvic abscesses. MATERIALS AND METHODS: Eighteen patients (four male, 14 female; mean age 55 years, range 30-78 years) presenting with pelvic abscesses were referred to our institution for therapeutic drainage over a 4 year period. Patients received broad-spectrum antibiotics prior to drainage, which was performed by either the transvaginal or transrectal route under ultrasound guidance. Patients were given sedo-analgesia in the form of midazolam and fentanyl and local anaesthesia was also employed. Eight French catheters were inserted into the abscess cavities, and patients were subsequently monitored on a daily basis by a member of the interventional radiology team until such time as it was deemed appropriate to remove the catheter. RESULTS: Eighteen catheters were placed in 17 patients, and transvaginal aspiration alone was performed in one patient. Drainage was successful in 16 of 17 patients, but a transgluteal approach was ultimately required in the remaining patient to enable passage of a larger catheter into an infected haematoma. The mean duration of drainage was 5 days, mean time to defervesce 2 days. Spontaneous catheter dislodgement occurred in four patients associated with straining, but this did not have any adverse effect in three of the four patients. CONCLUSION: Endocavitary drainage is an effective method of treatment for pelvic abscesses. Spontaneous catheter dislodgement does not affect patient outcome.

  17. Energy-aware Supply Voltage and Body Biasing Voltage Scheduling Algorithm for Real-time Distributed Systems

    Institute of Scientific and Technical Information of China (English)

    SUYajuan; WEIShaojun

    2005-01-01

    Technique of energy minimization by combining Dynamic voltage scheduling (DVS) and Adaptive body biasing voltage (ABB) method for distributed realtime system at design level is proposed. First, a simplified energy optimizing model is illustrated where the supply voltage or body biasing voltage is kept as constant according to each separated frequency region, thus calculation of exceeding equation is avoided. Divergence of simplified and analytic model within 5% indicates the accuracy of this model. Based on it, the proposed approach named LEVVS (Low energy supply voltage and body biasing voltage scheduling algorithm) explores space of minimizing energy consumption by finding optimal trade-off between dynamic and static energy. The corresponding optimal supply voltage and body biasing voltage are determined by an iterative method in which the supply voltage and body biasing voltage of tasks are adjusted according to the value of energy latency differential coefficient of each task and slack time distribution of the system. Experiments show that using LEVVS approach, 51% more average energy reduction can be obtained than employing DVS method alone. Furthermore the effects of switch capacitance and global slack on the energy saving efficiency of LEVVS are investigated. The smaller the global slack or average switch capacitance is, the more the energy saving of LEVVS compared with DVS is.

  18. No-Voltage Meter

    Science.gov (United States)

    1976-02-01

    VW- IKft, 1/4 H4 -Wv- IK!1, I/4W INTERNAL VOLTAGE NOTE ALL TRANSISTORS ARE 2N43A OR EQUIVALENT GERMANIUM ALLOY PNP AA ALKALINE BATTERY...D-,, regardless of polarity. This signal is then full-wave rectified by the diode-connected Germanium transistor bridge, T,, T-,, T3, and T4... Transistor T5 acts as a second current limiter. Resistor R2 was selected to give 90 f# of full-scale meter deflection with an input signal of 115 volts

  19. Urban Drainage Modeling and Flood Risk Management

    Science.gov (United States)

    Schmitt, Theo G.; Thomas, Martin

    The European research project in the EUREKA framework, RisUrSim (Σ!2255) has been worked out by a project consortium including industrial mathematics and water engineering research institutes, municipal drainage works as well as an insurance company. The overall objective has been the development of a simulation to allow flood risk analysis and cost-effective management for urban drainage systems. In view of the regulatory background of European Standard EN 752, the phenomenon of urban flooding caused by surcharged sewer systems in urban drainage systems is analyzed, leading to the necessity of dual drainage modeling. A detailed dual drainage simulation model is described based upon hydraulic flow routing procedures for surface flow and pipe flow. Special consideration is given to the interaction between surface and sewer flow in order to most accurately compute water levels above ground as a basis for further assessment of possible damage costs. The model application is presented for small case study in terms of data needs, model verification, and first simulation results.

  20. Benchmarking of Voltage Sag Generators

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

    2012-01-01

    The increased penetration of renewable energy systems, like photovoltaic and wind power systems, rises the concern about the power quality and stability of the utility grid. Some regulations for Low Voltage Ride-Through (LVRT) for medium voltage or high voltage applications, are coming into force...... to guide these grid-connected distributed power generation systems. In order to verify the response of such systems for voltage disturbance, mainly for evaluation of voltage sags/dips, a Voltage Sag Generator (VSG) is needed. This paper evaluates such sag test devices according to IEC 61000 in order...... to provide cheaper solutions to test against voltage sags. Simulation and experimental results demonstrate that the shunt impedance based VSG solution is the easiest and cheapest one for laboratory test applications. The back-to-back fully controlled converter based VSG is the most flexible solution...

  1. Abandonment of endoprosthetic drainage technique in malignant biliary obstruction.

    Science.gov (United States)

    Mendez, G; Russell, E; LePage, J R; Guerra, J J; Posniak, R A; Trefler, M

    1984-09-01

    This report discusses a 3-year experience with the techniques of internal/external catheter and endoprosthetic stent drainage in 175 patients with obstructive jaundice. In 166 patients, the obstruction was bypassed satisfactorily. The complications encountered with these techniques are compared, and the radiation doses involved are emphasized. It is not necessary to put patients through the extra time and pain related to the placement of the endoprosthesis, because internal/external catheter placement produces the same desired result of biliary decompression without the higher radiation doses to the radiologist.

  2. Coordinated Voltage Control of Distributed PV Inverters for Voltage Regulation in Low Voltage Distribution Networks

    DEFF Research Database (Denmark)

    Nainar, Karthikeyan; Pokhrel, Basanta Raj; Pillai, Jayakrishnan Radhakrishna

    2017-01-01

    This paper reviews and analyzes the existing voltage control methods of distributed solar PV inverters to improve the voltage regulation and thereby the hosting capacity of a low-voltage distribution network. A novel coordinated voltage control method is proposed based on voltage sensitivity...... analysis, which is simple for computation and requires moderate automation and communication infrastructure. The proposed method is suitable for a hierarchical control structure where a supervisory controller has the provision to adapt the settings of local PV inverter controllers for overall system...

  3. Heat-pump performance: voltage dip/sag, under-voltage and over-voltage

    Directory of Open Access Journals (Sweden)

    William J.B. Heffernan

    2014-12-01

    Full Text Available Reverse cycle air-source heat-pumps are an increasingly significant load in New Zealand and in many other countries. This has raised concern over the impact wide-spread use of heat-pumps may have on the grid. The characteristics of the loads connected to the power system are changing because of heat-pumps. Their performance during under-voltage events such as voltage dips has the potential to compound the event and possibly cause voltage collapse. In this study, results from testing six heat-pumps are presented to assess their performance at various voltages and hence their impact on voltage stability.

  4. Autogenic Drainage in Children With Cystic Fibrosis.

    Science.gov (United States)

    Corten, Lieselotte; Morrow, Brenda M

    2017-04-01

    Airway clearance is an essential part of the management of cystic fibrosis (CF) as it facilitates clearance of viscous pulmonary secretions. This review aimed to determine the effect of autogenic drainage (AD) and assisted autogenic drainage (AAD) compared with no, sham, or other types of airway clearance in children with CF. Two pediatric randomized cross-over trials were identified on the use of AD in children with CF; no studies were available on the use of AAD. In one study AD had a positive influence on the Huang score, and is preferred over postural drainage in this population. We could not determine the efficacy of AD and AAD in children with CF. We recommend the implementation of pediatric-specific randomized controlled trials with adequate sample sizes, appropriate clinical outcome measures, and analysis of adverse effects.

  5. Percutaneous epidural drainage through a burr hole

    Directory of Open Access Journals (Sweden)

    Priscila M Falsarella

    2016-01-01

    Full Text Available Intracranial extradural collection may cause an increase in intracranial pressure, requiring rapid emergency treatment to reduce morbidity and mortality. We described an alternative CT-guided percutaneous access for extradural collection drainage. We report a case of a patient with previous craniectomy for meningioma ressection who presented to the Emergency Department with symptoms of intracranial hypertension. Brains CT showed a extradural collection with subfalcine herniation. After multidisciplinary discussion a CT-guided percutaneous drainage through previous burr hole was performed. The patient was discharged after 36 hours of admission, without further symptoms. We describe a safe and effective alternative percutaneous access for extradural collection drainage in patients with previous burr hole.

  6. Voltage Swells Improvement in Low Voltage Network Using Dynamic Voltage Restorer

    Directory of Open Access Journals (Sweden)

    R. Omar

    2011-01-01

    Full Text Available Problem statement: Voltage disturbances are the most common power quality problem due to the increased use of a large numbers of sophisticated electronic equipment in industrial distribution system. The voltage disturbances such as voltage sags, swells, harmonics, unbalance and flickers. High quality in the power supply is needed, since failures due to such disturbances usually have a high impact on production cost. There are many different solutions to compensate voltage disturbances but the use of a DVR is considered to be the most cost effective method. The objective of this study is to propose a new topology of a DVR in order to mitigate voltage swells using a powerful power custom device namely the Dynamic Voltage Restorer (DVR. Approach: New configuration of a DVR with an improvement of a controller based on direct-quadrature-zero method has been introduced to compensate voltage swells in the network. Results: The effectiveness of the DVR with its controller were verify using Matlab/Simulinks SimPower Toolbox and then implemented using 5KVA DVR experimental setup. Simulations and experimental results demonstrate the effective dynamic performance of the proposed configuration. Conclusion: The implimentation of the proposed DVR validate the capabilities in mitigating of voltage swells effectiveness.During voltage swells, the DVR injects an appropriate voltage to maintain the load voltage at its nominal value.

  7. Isomerically Pure Tetramethylrhodamine Voltage Reporters.

    Science.gov (United States)

    Deal, Parker E; Kulkarni, Rishikesh U; Al-Abdullatif, Sarah H; Miller, Evan W

    2016-07-27

    We present the design, synthesis, and application of a new family of fluorescent voltage indicators based on isomerically pure tetramethylrhodamines. These new Rhodamine Voltage Reporters, or RhoVRs, use photoinduced electron transfer (PeT) as a trigger for voltage sensing, display excitation and emission profiles in the green to orange region of the visible spectrum, demonstrate high sensitivity to membrane potential changes (up to 47% ΔF/F per 100 mV), and employ a tertiary amide derived from sarcosine, which aids in membrane localization and simultaneously simplifies the synthetic route to the voltage sensors. The most sensitive of the RhoVR dyes, RhoVR 1, features a methoxy-substituted diethylaniline donor and phenylenevinylene molecular wire at the 5'-position of the rhodamine aryl ring, exhibits the highest voltage sensitivity to date for red-shifted PeT-based voltage sensors, and is compatible with simultaneous imaging alongside green fluorescent protein-based indicators. The discoveries that sarcosine-based tertiary amides in the context of molecular-wire voltage indicators prevent dye internalization and 5'-substituted voltage indicators exhibit improved voltage sensitivity should be broadly applicable to other types of PeT-based voltage-sensitive fluorophores.

  8. High Voltage in Noble Liquids for High Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Rebel, B. [Fermilab; Bernard, E. [Yale U.; Faham, C. H. [LBL, Berkeley; Ito, T. M. [Los Alamos; Lundberg, B. [Maryland U.; Messina, M. [Columbia U.; Monrabal, F. [Valencia U., IFIC; Pereverzev, S. P. [LLNL, Livermore; Resnati, F. [Zurich, ETH; Rowson, P. C. [SLAC; Soderberg, M. [Fermilab; Strauss, T. [Bern U.; Tomas, A. [Imperial Coll., London; Va' vra, J. [SLAC; Wang, H. [UCLA

    2014-08-22

    A workshop was held at Fermilab November 8-9, 2013 to discuss the challenges of using high voltage in noble liquids. The participants spanned the fields of neutrino, dark matter, and electric dipole moment physics. All presentations at the workshop were made in plenary sessions. This document summarizes the experiences and lessons learned from experiments in these fields at developing high voltage systems in noble liquids.

  9. Voltage Dependence of Supercapacitor Capacitance

    Directory of Open Access Journals (Sweden)

    Szewczyk Arkadiusz

    2016-09-01

    Full Text Available Electronic Double-Layer Capacitors (EDLC, called Supercapacitors (SC, are electronic devices that are capable to store a relatively high amount of energy in a small volume comparing to other types of capacitors. They are composed of an activated carbon layer and electrolyte solution. The charge is stored on electrodes, forming the Helmholtz layer, and in electrolyte. The capacitance of supercapacitor is voltage- dependent. We propose an experimental method, based on monitoring of charging and discharging a supercapacitor, which enables to evaluate the charge in an SC structure as well as the Capacitance-Voltage (C-V dependence. The measurement setup, method and experimental results of charging/discharging commercially available supercapacitors in various voltage and current conditions are presented. The total charge stored in an SC structure is proportional to the square of voltage at SC electrodes while the charge on electrodes increases linearly with the voltage on SC electrodes. The Helmholtz capacitance increases linearly with the voltage bias while a sublinear increase of total capacitance was found. The voltage on SC increases after the discharge of electrodes due to diffusion of charges from the electrolyte to the electrodes. We have found that the recovery voltage value is linearly proportional to the initial bias voltage value.

  10. Pericardial drainage for pericardial tamponade: surgical management criteria.

    Science.gov (United States)

    Ballore, L; Nicolini, F; Borrello, B; Beghi, C; De Cicco, G; Contini, G A; Gherli, T

    2001-01-01

    Aim of this study is the review of our experience in 82 patients treated by pericardial drainage for cardiac tamponade, to assess the efficacy and safety of different techniques and the related indications. The causes of pericardial effusion were: malignancy in 8 patients (9.7%), post-cardiac surgery in 12 (14.6%), while the others patients were admitted at our Institution with no identified preoperative diagnosis. Thirty-eight patients (46%) underwent subxiphoid pericardial drainage and 44 (54%) were operated on by catheter pericardiocentesis. There were no perioperative deaths. Two patients, who initially underwent pericardiocentesis, needed urgent sternotomy: the first patient developed a severe hypotension and bradicardia related to a vagal reaction and the other one because of accidental right ventricle puncture. Our experience indicates that subxiphoid pericardiocentesis provides expeditious, effective and durable treatment, with low morbidity, in case of pericardial effusions related to all causes. We believe that echocardiography is a powerful tool in the diagnosis and management of pericardial effusion. We conclude that pericardiocentesis seems to be the procedure of choice for patients with pericardial tamponade requiring an emergency treatment.

  11. Urban drainage models - making uncertainty analysis simple

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen; Deletic, Ana

    2012-01-01

    There is increasing awareness about uncertainties in modelling of urban drainage systems and, as such, many new methods for uncertainty analyses have been developed. Despite this, all available methods have limitations which restrict their widespread application among practitioners. Here, a modif...

  12. 24 CFR 3280.610 - Drainage systems.

    Science.gov (United States)

    2010-04-01

    ... designs the system for site assembly and also provides all materials and components, including piping... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Drainage systems. 3280.610 Section 3280.610 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued...

  13. Reality named endoscopic ultrasound biliary drainage

    Institute of Scientific and Technical Information of China (English)

    Hugo; Gon?alo; Guedes; Roberto; Iglesias; Lopes; Joel; Fernandez; de; Oliveira; Everson; Luiz; de; Almeida; Artifon

    2015-01-01

    Endoscopic ultrasound(EUS) is used for diagnosis and evaluation of many diseases of the gastrointestinal (GI) tract. In the past, it was used to guide a cholangio-graphy, but nowadays it emerges as a powerful thera-peutic tool in biliary drainage. The aims of this review are: outline the rationale for endoscopic ultrasound-guided biliary drainage(EGBD); detail the procedural technique; evaluate the clinical outcomes and limitations of the method; and provide recommendations for the practicing clinician. In cases of failed endoscopic retro-grade cholangiopancreatography(ERCP), patients are usually referred for either percutaneous transhepatic biliary drainage(PTBD) or surgical bypass. Both these procedures have high rates of undesirable complications. EGBD is an attractive alternative to PTBD or surgery when ERCP fails. EGBD can be performed at two locations: transhepatic or extrahepatic, and the stent can be inserted in an antegrade or retrograde fashion. The drainage route can be transluminal, duodenal or trans-papillary, which, again, can be antegrade or retrograde [rendezvous(EUS-RV)]. Complications of all techniques combined include pneumoperitoneum, bleeding, bile leak/peritonitis and cholangitis. We recommend EGBD when bile duct access is not possible because of failed cannulation, altered upper GI tract anatomy, gastric outlet obstruction, a distorted ampulla or a periampullary diverticulum, as a minimally invasive alternative to surgery or radiology.

  14. [Artificial drainage devices--history, indications].

    Science.gov (United States)

    Barac, Ileana Ramona; Pop, Monica

    2012-01-01

    Glaucoma is a degenerative optic neuropathy progressive, multifactorial, which can lead to blindness. Blindness in patients with glaucoma is defined as visual field reduction below 10 degrees. Artificial drainage systems are a solution for refractory to medication, laser treatment or conventional surgery. Used by over 100 years, improved with good surgical technique and careful patient follow-up surgery, postoperative results are satisfactory.

  15. Optimizing the closed suction surgical drainage system.

    Science.gov (United States)

    Carruthers, Katherine H; Eisemann, Bradley S; Lamp, Susan; Kocak, Ergun

    2013-01-01

    Closed suction drains are indicated in a wide array of postoperative settings, with many distinct drainage systems available to the surgeon. The purpose of this study was to compare the suction gradients achieved using 2 different sizes of suction reservoirs and 2 different techniques for generating negative pressure. Drainage reservoirs of 100 and 400 ml were chosen to evaluate their ability to achieve suction. Suction was established in both sizes of drains by pressing the sides of the reservoir together or by pushing the bottom of the reservoir toward the top. Negative pressures were recorded with the reservoir empty, and after every 10-ml addition of saline. Averages were graphed to illustrate the applied suction over a range of drain volumes. The 100-ml drainage system reached a peak suction of -117.6 mmHg, while the 400-ml drainage system reached only a peak suction of -71.4 mmHg. Both of the maximum suction readings were achieved using the full-squeeze technique. The bottom-pushed-in technique did not result in any sustained measurable levels of suction using either of the reservoir volumes. Smaller drain reservoirs are more successful in generating a high initial suction than larger reservoirs, especially when the volume of fluid in the drain is relatively low. In all sizes of drains, compressing the sides of the reservoir is a far better technique for establishing negative pressure than pressing the bottom of the drain up toward the top.

  16. Selecting the drainage method for agricultural land

    NARCIS (Netherlands)

    Bos, M.G.

    2001-01-01

    To facilitate crop growth excess water should be drained from the rooting zone to allow root development of the crop and from the soil surface to facilitate access to the field. Basically, there are three drainage methods from which the designer can select being; surface drains, pumped tube wells an

  17. Drainage hydraulics of permeable friction courses

    Science.gov (United States)

    Charbeneau, Randall J.; Barrett, Michael E.

    2008-04-01

    This paper describes solutions to the hydraulic equations that govern flow in permeable friction courses (PFC). PFC is a layer of porous asphalt approximately 50 mm thick that is placed as an overlay on top of an existing conventional concrete or asphalt road surface to help control splash and hydroplaning, reduce noise, and enhance quality of storm water runoff. The primary objective of this manuscript is to present an analytical system of equations that can be used in design and analysis of PFC systems. The primary assumptions used in this analysis are that the flow can be modeled as one-dimensional, steady state Darcy-type flow and that slopes are sufficiently small so that the Dupuit-Forchheimer assumptions apply. Solutions are derived for cases where storm water drainage is confined to the PFC bed and for conditions where the PFC drainage capacity is exceeded and ponded sheet flow occurs across the pavement surface. The mathematical solutions provide the drainage characteristics (depth and residence time) as a function of rainfall intensity, PFC hydraulic conductivity, pavement slope, and maximum drainage path length.

  18. Impact of land drainage on peatland hydrology.

    Science.gov (United States)

    Holden, J; Evans, M G; Burt, T P; Horton, M

    2006-01-01

    There is a long history of drainage of blanket peat but few studies of the long-term hydrological impact of drainage. This paper aims to test differences in runoff production processes between intact and drained blanket peat catchments and determine whether there have been any long-term changes in stream flow since drainage occurred. Hillslope runoff processes and stream discharge were measured in four blanket peat catchments. Two catchments were drained with open-cut ditches in the 1950s. Ditching originally resulted in shorter lag times and flashier storm hydrographs but no change in the annual catchment runoff efficiency. In the period between 2002 and 2004, the hydrographs in the drained catchments, while still flashy, were less sensitive to rainfall than in the 1950s and the runoff efficiency had significantly increased. Drains resulted in a distinctive spatial pattern of runoff production across the slopes. Overland flow was significantly lower in the drained catchments where throughflow was more dominant. In the intact peatlands, matrix throughflow produced by peat layers below 10 cm was rare and produced structure could explain the long-term changes in river flow, which are in addition to those occurring in the immediate aftermath of peatland drainage.

  19. Interventional radiology in the lacrimal drainage system

    Energy Technology Data Exchange (ETDEWEB)

    Ilgit, Erhan T. [Department of Radiology, School of Medicine, Gazi University, Besevler 06510, Ankara (Turkey)]. E-mail: erhanti@gazi.edu.tr; Oenal, Baran [Department of Radiology, School of Medicine, Gazi University, Besevler 06510, Ankara (Turkey); Coskun, Bilgen [Department of Radiology, School of Medicine, Gazi University, Besevler 06510, Ankara (Turkey)

    2005-09-01

    This article presents a review of the interventional radiological procedures in the lacrimal drainage system. Balloon dacryocystoplasty and nasolacrimal polyurethane stent placement are the main fluoroscopically guided interventions for the treatment of epiphora by recanalizing the obstructed LDS. These procedures can also be used for dacryolith removal and lacrimal sac abscess treatment.

  20. The role of antecedent drainage networks and isolated normal fault propagation on basin stratigraphy

    Science.gov (United States)

    Finch, E.; Brocklehurst, S. H.; Gawthorpe, R.

    2010-12-01

    The stratigraphy of an extensional basin reflects a history of fault activity, erosion, drainage network evolution, and sediment transport and deposition. Here a three-dimensional numerical model of erosion and clastic sedimentation is applied to investigate the effect of displacement on a normal fault to the distribution of deposition in an extensional basin. Material is eroded from the hinterland through a stream-power incision law and deposited in the basin using a modified diffusion algorithm. Experiments are implemented for 3Ma, in which the initial 1Ma are used to permit a drainage network to evolve to a topographic steady state. This system is then perturbed by the introduction of a propagating isolated normal fault at varying displacement rates (1.0m/kyr - 2.0m/kyr) to demonstrate the influence of fault propagation on drainage capture, network re-organisation, sediment routing and deposition. Faster displacement rates and smaller antecedent drainage networks cause footwall-derived deltas to be cut-off more rapidly from the hinterland source area. Drainage networks are re-organised such that sediment is then transported around the fault tips into axially sourced deltas. Sediments may continue to be deposited in the hanging wall at the fault centre, but this material has not been sourced directly from the adjacent footwall, even though the stratigraphic architecture might suggest that this is the case. Drainage networks are modified by drainage reversals in the antecedent channels, and the development of areas of abandoned/trapped drainage. These changes in sediment supply due to network re-organisation are also reflected in the basin stratigraphy, with rapid back-stepping of deltas when the source is removed in the adjacent footwall. Later incision and headward erosion of the footwall channels may cause re-capture of earlier channels, while network re-organisation may also cause depositional in-filling of earlier channels. The drainage divide shifts

  1. Topological Analysis of Urban Drainage Networks

    Science.gov (United States)

    Yang, Soohyun; Paik, Kyungrock; McGrath, Gavan; Rao, Suresh

    2016-04-01

    Urban drainage networks are an essential component of infrastructure, and comprise the aggregation of underground pipe networks carrying storm water and domestic waste water for eventual discharge to natural stream networks. Growing urbanization has contributed to rapid expansion of sewer networks, vastly increasing their complexity and scale. Importance of sewer networks has been well studied from an engineering perspective, including resilient management, optimal design, and malfunctioning impact. Yet, analysis of the urban drainage networks using complex networks approach are lacking. Urban drainage networks consist of manholes and conduits, which correspond to nodes and edges, analogous to junctions and streams in river networks. Converging water flows in these two networks are driven by elevation gradient. In this sense, engineered urban drainage networks share several attributes of flows in river networks. These similarities between the two directed, converging flow networks serve the basis for us to hypothesize that the functional topology of sewer networks, like river networks, is scale-invariant. We analyzed the exceedance probability distribution of upstream area for practical sewer networks in South Korea. We found that the exceedance probability distributions of upstream area follow power-law, implying that the sewer networks exhibit topological self-similarity. The power-law exponents for the sewer networks were similar, and within the range reported from analysis of natural river networks. Thus, in line with our hypothesis, these results suggest that engineered urban drainage networks share functional topological attributes regardless of their structural dissimilarity or different underlying network evolution processes (natural vs. engineered). Implications of these findings for optimal design of sewer networks and for modeling sewer flows will be discussed.

  2. Effect of state feedback coupling on the transient performance of voltage source inverters with LC filter

    DEFF Research Database (Denmark)

    Federico, de Bosio; Pastorelli, Michele; Antonio DeSouza Ribeiro, Luiz

    2016-01-01

    State feedback coupling between the capacitor voltage and inductor current deteriorates notably the performance during transients of voltage and current regulators in stand-alone systems based on voltage source inverters. A decoupling technique is proposed, considering the limitations introduced ...... by system delays. Laboratory experiments were executed in compliance with the normative for Uninterruptible Power Supply systems to prove the developed analysis....

  3. Exit and Paradise Creek Drainage Area Boundaries, Alaska, 2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset contains drainage area boundaries for Exit Creek and Paradise Creek in Kenai Fjords National Park, Alaska. A drainage area boundary identifies the land...

  4. Clinical outcome of routine drainage in simple laparoscopic cholecystectomy

    Directory of Open Access Journals (Sweden)

    LIANG Zongchao

    2013-03-01

    Full Text Available ObjectiveTo retrospectively review outcomes of elective laparoscopic cholecystectomy (LC to evaluate the benefit of routine drainage in uncomplicated surgeries. MethodsTwo-hundred-and-ninety-five patients with cholecystolithiasis or gallbladder polyps who underwent LC with drainage (n=145 and or without drainage (n=150 between 2009 and 2011 were enrolled in the study. The decision for drainage was randomized. ResultsThe LC without drainage group had significantly shorter time to first flatus and shorter length of postoperative hospital stay than the LC with drainage group. One patient in the drainage group developed an intra-abdominal abscess, but there was no significant difference between the two LC groups with respect to overall postoperative complication rate. ConclusionApplication of a peritoneal drainage tube after simple elective, uncomplicated LC did not provide any clinical benefit to the patients, and should be considered according to the operating physician′s judgment on a case-by-case basis.

  5. A Theoretical Study of Subsurface Drainage Model Simulation of ...

    African Journals Online (AJOL)

    A Theoretical Study of Subsurface Drainage Model Simulation of Drainage Flow and ... of subsurface drain spacing, evapotranspiration and irrigation water quality on ... The study was carried out on a conceptual uniform homogenous irrigated ...

  6. An investigation of breakdown voltage in AMTECs

    Science.gov (United States)

    Momozaki, Yoichi; El-Genk, Mohamed S.

    2002-01-01

    Experiments are conducted to investigate the DC electrical breakdown voltage in cesium vapor between two planner molybdenum electrodes, 1.6 cm in diameter, separated by a 0.5 mm gap, and relate the results to the potential electrical breakdown on the cathode side of Alkali Metal Thermal-to-Electric Converters (AMTECs). In the first set of experiments, in which the electrodes are kept at 560 and 650 K, while varying the cesium pressure from 0.71 to 29 Pa, when the cooler electrode is positively biased, breakdown occurs at ~500 V, but at 700 V when the cooler electrode is negatively biased. In the second set of experiments, in which the electrodes are held at 625 and 1100 K and the cesium pressure varied from 1.7 to 235 Pa, when the cooler electrode is positively biased, breakdown voltage is <4 V, but in excess of 400 V when the cooler electrode is negatively biased. Since the first ionization potential and the ionization rate constant of cesium are lower and higher, respectively, than for the sodium (5.14 V) and potassium (4.34 V) vapors in AMTECs, the DC electrical breakdown voltage in an AMTEC is expected to be higher than measured in this work for cesium vapor. .

  7. Living and Working Safely Around High-Voltage Power Lines.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2001-06-01

    High-voltage transmission lines can be just as safe as the electrical wiring in the homes--or just as dangerous. The crucial factor is ourselves: they must learn to behave safely around them. This booklet is a basic safety guide for those who live and work around power lines. It deals primarily with nuisance shocks due to induced voltages, and with potential electric shock hazards from contact with high-voltage lines. References on possible long-term biological effects of transmission lines are shown. In preparing this booklet, the Bonneville Power Administration has drawn on more than 50 years of experience with high-voltage transmission. BPA operates one of the world`s largest networks of long-distance, high-voltage lines. This system has more than 400 substations and about 15,000 miles of transmission lines, almost 4,400 miles of which are operated at 500,000 volts.

  8. 46 CFR 178.420 - Drainage of cockpit vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of cockpit vessels. (a) Except as follows, the cockpit on a cockpit vessel may be watertight: (1) A cockpit may...

  9. Investigation of enhancement of steam condensation heat transfer on finned tubes with porous drainage strips

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xijuan; Ma Tongze; Zhang Zhengfang

    1999-07-01

    Condensation of steam on horizontal finned tube with porous drainage strip was investigated experimentally and theoretically. Composite metal screens were used as porous drainage strip. Distilled water was taken in the experiments as working fluid. The experiments were carried out to find the structure effects of composite screen drainage strip on the condensation heat transfer on finned tubes with fin spacing of 0.5mm. Influences of the mesh number of both outer and inner layers and of length and thickness of the drainage strip were investigated. The outer layers of the screens have the mesh numbers of 100, 150, 185 and 220, which lead to different effective pore radius; the inner layers have the mesh numbers of 20, 30 and 40, which lead to different permeability. Strip lengths are 15mm, 20mm and 30mm, while the thickness is 2mm, 4mm and 6mm. Experimental results show that the structure parameters of the porous drainage strip strongly influence condensation on the finned tube. A porous strip having small effective pore radius on the outer layer as well as large permeability, reasonably large length and thickness will lead to excellent performance. In the tested ranges, for steam condensation on a 0.5mm spacing finned tube, the optimum structure of a composite screen drainage strip is of 150 mesh outer layer screen, 20 mesh inner layer screen, 30mm long and 4mm thick. The enhanced condensation heat transfer coefficients are equivalent to 1.15{approximately}1.74 times that of the finned tube and 2.08{approximately}3.08 times that of the plain tube. A new prediction model of condensation on finned tube with porous drainage strip was established. The condensate flow in the interfin grooves and in the porous strip was treated as flow through two kinds of porous medium with different structures. The momentum equation of single phase flow in porous medium was used to solve the condensate flow. The equation was analyzed and several terms were neglected because of their

  10. Evaluation of design factors for a cascade aerator to enhance the efficiency of an oxidation pond for ferruginous mine drainage.

    Science.gov (United States)

    Oh, Chamteut; Ji, Sangwoo; Cheong, Youngwook; Yim, Giljae; Hong, Ji-Hye

    2016-10-01

    This research focused on the optimum design of a cascade aerator to enhance the efficiency of an oxidation pond in a passive treatment system for remediating ferruginous mine drainage. For this purpose, various aeration experiments with aerators of different drop heights (0-4 m) and formations (types A and B) were executed on mine drainage. Type A simply drops the mine drainage into the oxidation pond while type B sprays the mine drainage and retains it for 8 min in each step. The efficiency enhancement of the oxidation pond was strongly dependent on the increase in pH and DO of the mine drainage discharged into the pond. The water quality improved with the increase in drop height but especially showed better effect with type B. The reasons for this result were attributed to the increase of contact surface and retention time of the mine drainage. The cascade aerator, therefore, should be designed to be as high as possible with the assistance of spraying form and retention time of the mine drainage to maximize the efficiency of the oxidation pond. These effects could be evaluated by calculating required areas of the oxidation pond for 95% of Fe(2+) oxidation.

  11. The Role of Geochemical Modeling in Predicting Quality Evolution of Acid Mine Drainage

    Directory of Open Access Journals (Sweden)

    Andrea Šlesárová

    2004-12-01

    Full Text Available In recent years the massive reduction of raw materials production brings a wide scale of problems. Among the most frequent exposes of mining activities belong besides old spoil heaps and sludge lagoons, also the drainage of acidic and highly mineralized mine waters known as “the Acid Mine Drainage” (thereinafter AMD from old mine workings. The acid mine drainage presents to the surrounding environment a massive problem. These waters are toxic to the plant and animal life, including fishes and aquatic insects. The primary control of the drainage pH and the metal content is the exposure of sulphide minerals to weathering, the availability of atmospheric oxygen, and the sensitivity of non-sulphide minerals to buffer acidity. A geochemical modeling software is increasingly used to solve evolution of the complex chemical systems such as the interaction of acid mine drainage with wall rocks, migration of AMD components. Beyond the better computer facilities it allows to study of thermodynamic properties substances and to enlarge thermodynamic databases. A model is a simplified version of reality based on its observation and experiments. A goal of the modeling process is the tendency to better understand processes taking place inside of the system, the attempt to assume the system’s behaviour in the future or to predict the effect of changed conditions in the system’s environment on the system itself.

  12. The flocculation research on treating suspended solids contained mine drainage through goaf

    Institute of Scientific and Technical Information of China (English)

    FENG Li-li; ZHU Yue-lin; SHAN Ai-qin; CHEN Suo-zhong

    2005-01-01

    Mine drainage could be filtered and purified through goaf. This innovative technique shows merits, such as high treatment efficiency, remarkable economic benefit and extensive wastewater recycle use. However, it was detected that capacities of purifying mine drainage for goaf were decreased after a period of application. As a result, the effluent could not meet the standard of recycle water. To solve the problem, coagulant was considered to add into mine drainage reducing its high turbid degrees to certain level. After the preliminary flocculation treatment, mine drainage was piped into goaf to purify. In this way, the load of goaf was eased up. Its usage time was also prolonged. Therefore, this paper carried out the coagulation-flocculation jar test for mine drainage to discuss the flocculation parameters. By the experiment, 10 % iron trichloride is selected from four inorganic coagulants as the optimum coagulant. The optimum dose, PH value and sedimentation time are respectively 2 mL per 800 mL wastewater,6~7 and 25 min. Velocity gradient G during the process of mixing and reaction is 696 s-1 .And the value of GT is 6.264× 105. The values of G and GT will supply the basis for the design of flocculation pool in the project. The flocculation parameters will be significant for the reference of practice.

  13. Crossover from shear-driven to thermally activated drainage of liquid-infused microscale capillaries

    Science.gov (United States)

    Colosqui, Carlos E.; Wexler, Jason S.; Liu, Ying; Stone, Howard A.

    2016-10-01

    The shear-driven drainage of capillary grooves filled with viscous liquid is a dynamic wetting phenomenon relevant to numerous industrial processes and lubricant-infused surfaces for drag reduction and antifouling. Prior work has reported that a finite length L∞ of the capillary groove can remain indefinitely filled with liquid even when large shear stresses are applied. The mechanism preventing full drainage is attributed to a balance between the shear-driven flow and a counterflow driven by capillary pressures caused by deformation of the free surface. In this work, we examine closely the approach to the final equilibrium length L∞ and report a crossover to a slow drainage regime that cannot be described by conventional dynamic models considering solely hydrodynamic and capillary forces. The slow drainage regime observed in experiments can be instead modeled by a kinetic equation describing a sequence of random thermally activated transitions between multiple metastable states caused by surface defects with nanoscale dimensions. Our findings provide insights on the critical role that natural or engineered surface roughness with nanoscale dimensions can play in the imbibition and drainage of capillaries and other dynamic wetting processes in microscale systems.

  14. Description, instructions, and verification for Basinsoft, a computer program to quantify drainage- basin characteristics

    Science.gov (United States)

    Harvey, Craig A.; Eash, David A.

    1996-01-01

    Basinsoft is a computer program developed to utilize digital cartographic data to quantify 27 selected morphometric characteristics and optional area-weighted characteristics for a drainage basin. The programs comprising Basinsoft were written in Arc Macro Language (AML), a post-processing language written to run in ARC/INFO, a proprietary geographic information system (GIS). Basinsoft requires the generation of four source-data layers, three coverages and one lattice, representing the drainage-divide, hydrography, hypsography, and a lattice elevation model of a drainage basin, and the attribution of the three source-data layer coverages. Preprocessing of these data layers is facilitated by specialized utility AML programs. Compared to manual methods of measurement, Basinsoft significantly decreases the amount of time and effort required to quantify selected characteristics for drainage basins, particularly when a large number of drainage basins need to be processed. The automaticity of Basinsoft and its utility programs facilitate implementation of Basinsoft without requiring extensive GIS experience. Basinsoft was developed entirely using AML to ensure portability between platforms running ARC/INFO version 7.0 or later.

  15. EFFECTIVENESS OF AUTOGENIC DRAINAGE VERSUS POSTURAL DRAINAGE ON OXYGEN SATURATION IN PATIENTS WITH CHRONIC BRONCHITIS WITH 15 MINUTES POST THERAPY

    OpenAIRE

    Kiran, V.; Dr. Bhimasen .S; E. Mastanaiah; A. Thiruppathi

    2014-01-01

    Background: Patients with COPD will have more amount of secretions. To clear the secretions by using of different bronchial hygiene techniques like postural drainage and autogenic drainage technique, manual hyperventilation technique ,active cycle breathing technique .Hence in this study to compare the short-term effects of postural drainage with clapping (PD) and autogenic drainage (AD) on level of oxygen saturation in blood, and amount of sputum recovery. Methodology: The study was done ...

  16. The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

    Directory of Open Access Journals (Sweden)

    Jenčárová Jana

    2015-06-01

    Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

  17. Drainage or Packing of the Sella? Transsphenoidal Surgery for Primary Pituitary Abscess: Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Soichi Oya

    2009-01-01

    Full Text Available The detailed surgical procedure of the transsphenoidal surgery for pituitary abscess has scarcely been described previously because it is a very rare clinical entity. The authors reported two cases of primary pituitary abscess. In case 1, the anterior wall of the sella turcica was reconstructed with the vomer bone after irrigating the abscess cavity, but the sella was not packed by fat for fear of the persistent infection by devascularized tissues. This led to the postoperative meningocele, the cerebrospinal fluid leak, and bacterial meningitis despite the successful abscess drainage. In case 2, tight sellar packing and reconstruction of the sellar wall were performed to avoid these postoperative complications, which resulted in complete drainage and uneventful postoperative course. Although accumulation of more cases is obviously needed to establish the definitive surgical technique in pituitary abscess surgery, our experience might suggest that packing of the sella is not impeditive for postoperative sufficient drainage.

  18. Acid mine drainage biogeochemistry at Iron Mountain, California

    Directory of Open Access Journals (Sweden)

    Gihring Thomas M

    2004-06-01

    Full Text Available The Richmond Mine at Iron Mountain, Shasta County, California, USA provides an excellent opportunity to study the chemical and biological controls on acid mine drainage (AMD generation in situ, and to identify key factors controlling solution chemistry. Here we integrate four years of field-based geochemical data with 16S rRNA gene clone libraries and rRNA probe-based studies of microbial population structure, cultivation-based metabolic experiments, arsenopyrite surface colonization experiments, and results of intermediate sulfur species kinetics experiments to describe the Richmond Mine AMD system. Extremely acidic effluent (pH between 0.5 and 0.9 resulting from oxidation of approximately 1 × 105 to 2 × 105 moles pyrite/day contains up to 24 g/1 Fe, several g/1 Zn and hundreds of mg/l Cu. Geochemical conditions change markedly over time, and are reflected in changes in microbial populations. Molecular analyses of 232 small subunit ribosomal RNA (16S rRNA gene sequences from six sites during a sampling time when lower temperature (0.8 conditions predominated show the dominance of Fe-oxidizing prokaryotes such as Ferroplasma and Leptospirillum in the primary drainage communities. Leptospirillum group III accounts for the majority of Leptospirillum sequences, which we attribute to anomalous physical and geochemical regimes at that time. A couple of sites peripheral to the main drainage, "Red Pool" and a pyrite "Slump," were even higher in pH (>1 and the community compositions reflected this change in geochemical conditions. Several novel lineages were identified within the archaeal Thermoplasmatales order associated with the pyrite slump, and the Red Pool (pH 1.4 contained the only population of Acidithiobacillus. Relatively small populations of Sulfobacillus spp. and Acidithiobacillus caldus may metabolize elemental sulfur as an intermediate species in the oxidation of pyritic sulfide to sulfate. Experiments show that elemental sulfur which

  19. Sustainable Drainage Practices in Spain, Specially Focused on Pervious Pavements

    Directory of Open Access Journals (Sweden)

    Jorge Rodriguez-Hernandez

    2013-01-01

    Full Text Available The Spanish climate is full of contrasts, with torrential rains and long droughts; under these conditions, appropriate water management is essential. In Spain, until the end of the twentieth century, water management and legislative development lagged behind other more developed countries. Nowadays, great efforts are being made to reverse this situation and improve both water management and legislation in order to control the two main problems related to stormwater management in cities: floods and diffuse pollution. In this context, Sustainable Urban Drainage Systems (SUDS were developed as the main solution to these problems. The study of these techniques started in the 1970s in the USA, but they were not studied in Spain until 1993 when the University of Cantabria and CLABSA started to look into solutions for stormwater management. After 20 years of research and application, sustainable drainage in Spain is still behind other countries in spite of the efforts to change this situation, notably by the University of Cantabria with 10 years of experience in these techniques, mainly regarding pervious pavements, where more than 13 related research projects have been carried out. The future challenges focus on the application of pervious pavements for Urban Hydrological Rehabilitation.

  20. Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes

    Energy Technology Data Exchange (ETDEWEB)

    Grin, A.; Lstiburek, J.

    2014-09-01

    This guide provides information and recommendations to the following groups: insulation contractors; general contractors; builders; home remodelers; mechanical contractors; and homeowners, as a guide to the work that needs to be done. The order of work completed during home construction and retrofit improvements is important. Health and safety issues must be addressed first and are more important than durability issues. And durability issues are more important than saving energy. Not all techniques can apply to all houses. Special conditions will require special action. Some builders or homeowners will wish to do more than the important but basic retrofit strategies outlined by this guide. The following are best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant items were discussed with the group which are required to make taped insulating sheathing a simple, long term, and durable drainage plane: 1. Horizontal joints should be limited or eliminated wherever possible; 2. Where a horizontal joint exists use superior materials; 3. Frequent installation inspection and regular trade training are required to maintain proper installation. Section 5 of this measure guideline contains the detailed construction procedure for the three recommended methods to effectively seal the joints in exterior insulating sheathing to create a simple, long term, and durable drainage plane.

  1. Thermokarst lakes, drainage, and drained basins

    Science.gov (United States)

    Grosse, G.; Jones, B.; Arp, C.; Shroder, John F.

    2013-01-01

    Thermokarst lakes and drained lake basins are widespread in Arctic and sub-Arctic permafrost lowlands with ice-rich sediments. Thermokarst lake formation is a dominant mode of permafrost degradation and is linked to surface disturbance, subsequent melting of ground ice, surface subsidence, water impoundment, and positive feedbacks between lake growth and permafrost thaw, whereas lake drainage generally results in local permafrost aggradation. Thermokarst lakes characteristically have unique limnological, morphological, and biogeochemical characteristics that are closely tied to cold-climate conditions and permafrost properties. Thermokarst lakes also have a tendency toward complete or partial drainage through permafrost degradation and erosion. Thermokarst lake dynamics strongly affect the development of landscape geomorphology, hydrology, and the habitat characteristic of permafrost lowlands.

  2. Autogenic drainage: efficacy of a simplified method.

    Science.gov (United States)

    Lindemann, H; Boldt, A; Kieselmann, R

    1990-01-01

    A simplified and modified technique of the original autogenic drainage (AD) is described which is supplemented by breathing against an external flow resistance. The new method allows a better teaching and learning. It's efficacy is proven by means of a comparative trial of AD and PEP physiotherapy (i.e. expiration against a defined stenosis). The autogenic drainage (AD) was introduced by a Belgian working group (2). The basic idea was to support the elimination of mucus by deep breathing and by repressing the cough as long as possible. However, a rather sophisticated method impeded teaching and learning of AD (1). Thus, till now, there are only preliminary results which suggest the efficacy of AD (e.g. 3). Therefore, a simplified technique was developed and examined with regard to its sputum eliminating effect.

  3. Range of drainage effect of surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Sozanski, J.

    1978-03-01

    This paper discusses methods of calculating the range of effects of water drainage from surface coal mines and other surface mines. It is suggested that methods based on test pumping (water drainage) are time consuming, and the results can be distorted by atmospheric factors such as rain fall or dry period. So-called empirical formulae produce results which are often incorrect. The size of a cone shaped depression calculated on the basis of empirical formulae can be ten times smaller than the size of the real depression. It is suggested that using a formula based on the Dupuit formula is superior to other methods of depression calculation. According to the derived formulae the radius of the depresion cone is a function of parameters of the water bearing horizons, size of surface mine working and of water depression. The proposed formula also takes into account the influence of atmospheric factors (water influx caused by precipitation, etc.). (1 ref.) (In Polish)

  4. Electric Vehicle IM Controller Based on Voltage-Fed Inverter

    Institute of Scientific and Technical Information of China (English)

    宋建国; 张承宁; 袁学; 谭建

    2004-01-01

    A novel electric vehicle (EV) induction motor (IM) controller based on voltage-fed inverter is presented. It is shown that the proposed adaptive control algorithm effectively both simplifies the structure and expands the capacity of controller. The relationship between stator's voltage and that of current under rotor's flux-oriented-coordinates is first introduced, and then the structure of vector control is analyzed, in which voltage compensation is inducted as the core feedback procedure. Experiments prove that, together with a facility for realization, a smooth transition, a prompt torque response and small concussion are gained. Extensive research conducted by varying parameters that result in practical ripple is proposed in conclusion.

  5. Mitigation of Voltage Swells by Static Series Compensator

    DEFF Research Database (Denmark)

    Awad, Hilmy; Blaabjerg, Frede

    2004-01-01

    is lower than a predetermined voltage level, the active power is employed to charge the ESC to this voltage level; 2) otherwise, the overvoltage protection of the SSC must operate. This paper also applies an overvoltage protection scheme based on a combination of a dc resistor with a chopper and the valves...... of the SSC. The design of the dc resistor is discussed. A 10 kV SSC experimental setup is exploited to carry out experiments in the case of balanced and unbalanced voltage swells at the grid side....

  6. Urban drainage models - making uncertainty analysis simple

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen; Deletic, Ana;

    2012-01-01

    There is increasing awareness about uncertainties in modelling of urban drainage systems and, as such, many new methods for uncertainty analyses have been developed. Despite this, all available methods have limitations which restrict their widespread application among practitioners. Here, a modif...... probability distributions (often used for sensitivity analyses) and prediction intervals. To demonstrate the new method, it is applied to a conceptual rainfall-runoff model using a dataset collected from Melbourne, Australia....

  7. Factors influencing pleural drainage in parapneumonic effusions.

    Science.gov (United States)

    Porcel, J M; Valencia, H; Bielsa, S

    2016-10-01

    The identification of parapneumonic effusions (PPE) requiring pleural drainage is challenging. We aimed to determine the diagnostic accuracy of radiological and pleural fluid findings in discriminating between PPE that need drainage (complicated PPE (CPPE)) and those that could be resolved with antibiotics only (uncomplicated PPE (UPPE)). A retrospective review of 641 consecutive PPE, of which 393 were categorized as CPPE and 248 as UPPE. Demographics, radiological (size and laterality on a chest radiograph) and pleural fluid parameters (pus, bacterial cultures, biochemistries) were compared among groups. Logistic regression was performed to determine variables useful for predicting chest drainage, and receiver-operating characteristic curves assisted in the selection of the best cutoff values. According to the likelihood ratios (LR), findings increasing the probability of chest tube usage the most were: effusions occupying ≥1/2 of the hemithorax (LR 13.5), pleural fluid pH ≤7.15 (LR 6.2), pleural fluid glucose ≤40mg/dL (LR 5.6), pus (LR 4.8), positive pleural fluid cultures (LR 3.6), and pleural fluid lactate dehydrogenase >2000U/L (LR 3.4). In the logistic regression analysis only the first two were selected as significant predictors of CPPE. In non-purulent effusions, the effusion's size and pleural fluid pH retained their discriminatory properties, in addition to a pleural fluid C-reactive protein (CRP) level >100mg/L. Large radiological effusions and a pleural fluid pH ≤7.15 were the best predictors for chest drainage in patients with PPE. In the subgroup of patients with non-purulent effusions, pleural fluid CRP also contributed to CPPE identification. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  8. High-voltage test and measuring techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hauschild, Wolfgang; Lemke, Eberhard

    2014-04-01

    Reflects the unit of both HV testing and measuring technique. Intended as an ''application guide'' for the relevant IEC standards. Refers also to future trends in HV testing and measuring technique. With numerous illustrations. It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  9. Drainage and Stratification Kinetics of Foam Films

    Science.gov (United States)

    Zhang, Yiran; Sharma, Vivek

    2014-03-01

    Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Foam lifetime, drainage kinetics and stability are strongly influenced by surfactant type (ionic vs non-ionic), and added proteins, particles or polymers modify typical responses. The rate at which fluid drains out from a foam film, i.e. drainage kinetics, is determined in the last stages primarily by molecular interactions and capillarity. Interestingly, for certain low molecular weight surfactants, colloids and polyelectrolyte-surfactant mixtures, a layered ordering of molecules, micelles or particles inside the foam films leads to a stepwise thinning phenomena called stratification. Though stratification is observed in many confined systems including foam films containing particles or polyelectrolytes, films containing globular proteins seem not to show this behavior. Using a Scheludko-type cell, we experimentally study the drainage and stratification kinetics of horizontal foam films formed by protein-surfactant mixtures, and carefully determine how the presence of proteins influences the hydrodynamics and thermodynamics of foam films.

  10. Drawdown behavior of gravity drainage wells

    Energy Technology Data Exchange (ETDEWEB)

    Aasen, J.A.; Ramey, H.J. Jr.

    1993-10-01

    An analytical solution for drawdown in gravity drainage wells is developed. The free-surface flow is viewed as incompressible, and anisotropy effects are included. The well is a line source well, and the reservoir is infinitely large. The model is valid for small drawdowns. The uniform wellbore potential inner boundary condition is modelled using the proper Green`s function. The discontinuity at the wellbore is solved by introducing a finite skin radius, and the formulation produces a seepage face. The calculated wellbore flux distribution and wellbore pressures are in fair agreement with results obtained using a numerical gravity drainage simulator. Three distinct flow periods are observed. The wellbore storage period is caused by the moving liquid level, and the duration is short. During the long intermediate flow period, the wellbore pressure is nearly constant. In this period the free surface moves downwards, and the liquid is produced mainly by vertical drainage. At long times the semilog straight line appears. The confined liquid solutions by Theis (1935) and van Everdingen and Hurst (1949) may be used during the pseudoradial flow period if the flowrate is low. New type curves are presented that yield both vertical and horizontal permeabilities.

  11. Treatment of severe acute pancreatitis through retroperitoneal laparoscopic drainage

    Institute of Scientific and Technical Information of China (English)

    Chun Tang; Baolin Wang; Bing Xie; Hongming Liu; Ping Chen

    2011-01-01

    A treatment method based on drainage via retroperitoneal laparoscopy was adopted for 15 severe acute pancreatitis (SAP) patients to investigate the feasibility of the method.Ten patients received only drainage via retroperitoneai laparoscopy,four patients received drainage via both retroperitoneal and preperitoneal laparoscopy,and one patient received drainage via conversion to laparotomy.Thirteen patients exhibited a good drainage effect and were successfully cured without any other surgical treatment.Two patients had encapsulated effusions or pancreatic pseudocysts after surgery,but were successfully cured after lavage and B ultrasound-guided percutaneous catheter drainage.SAP treatment via retroperitoneal laparoscopic drainage is an effective surgical method,resulting in minor injury.

  12. Voltage Sensors Monitor Harmful Static

    Science.gov (United States)

    2009-01-01

    A tiny sensor, small enough to be worn on clothing, now monitors voltage changes near sensitive instruments after being created to alert Agency workers to dangerous static buildup near fuel operations and avionics. San Diego s Quasar Federal Systems received a Small Business Innovation Research (SBIR) contract from Kennedy Space Center to develop its remote voltage sensor (RVS), a dime-sized electrometer designed to measure triboelectric changes in the environment. One of the unique qualities of the RVS is that it can detect static at greater distances than previous devices, measuring voltage changes from a few centimeters to a few meters away, due to its much-improved sensitivity.

  13. Echo voltage reflected by turtle on various angles

    OpenAIRE

    Sunardi Sunardi; Anton Yudhana; Azrul Mahfurdz; Sharipah Salwa Mohamed

    2015-01-01

    This research proposes the acoustic measurement by using echo sounder for green turtle detection of 1 year, 12 and 18 years. Various positions or angles of turtles are head, tail, shell, lung, left and right side. MATLAB software and echo sounder are used to analyse the frequency and the response of the turtle as echo voltage and target strength parameter. Based on the experiment and analysis have been conducted, the bigger size of the turtle, the higher echo voltage and target strength. The ...

  14. Preoperative biliary drainage for periampullary tumors causing obstructive jaundice; DRainage vs. (direct OPeration (DROP-trial

    Directory of Open Access Journals (Sweden)

    Sosef Meindert N

    2007-03-01

    Full Text Available Abstract Background Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to improve the general condition and thus reduce postoperative morbidity and mortality. Early studies showed a reduction in morbidity. However, more recently the focus has shifted towards the negative effects of drainage, such as an increase of infectious complications. Whether biliary drainage should always be performed in jaundiced patients remains controversial. The randomized controlled multicenter DROP-trial (DRainage vs. Operation was conceived to compare the outcome of a 'preoperative biliary drainage strategy' (standard strategy with that of an 'early-surgery' strategy, with respect to the incidence of severe complications (primary-outcome measure, hospital stay, number of invasive diagnostic tests, costs, and quality of life. Methods/design Patients with obstructive jaundice due to a periampullary tumor, eligible for exploration after staging with CT scan, and scheduled to undergo a "curative" resection, will be randomized to either "early surgical treatment" (within one week or "preoperative biliary drainage" (for 4 weeks and subsequent surgical treatment (standard treatment. Primary outcome measure is the percentage of severe complications up to 90 days after surgery. The sample size calculation is based on the equivalence design for the primary outcome measure. If equivalence is found, the comparison of the secondary outcomes will be essential in selecting the preferred strategy. Based on a 40% complication rate for early surgical treatment and 48% for preoperative drainage, equivalence is taken to be demonstrated if the percentage of severe complications with early surgical treatment is not more than 10% higher compared to standard treatment

  15. Closed suction drainage versus closed simple drainage in the management of modified radical mastectomy wounds.

    Science.gov (United States)

    Ezeome, E R; Adebamowo, C A

    2008-09-01

    To compare the outcomes of modified radical mastectomy wounds managed by closed wound drainage with suction and without suction. A prospective randomised trial was conducted at the University College Hospital in Ibadan, and the University of Nigeria Teaching Hospital in Enugu. Fifty women who required modified radical mastectomy for breast cancer were randomised to have closed wound drainage with suction (26 patients) and closed wound drainage without suction (24 patients). There was no significant difference in the intraoperative and postoperative variables. Suction drainage drained less volume of fluid and stayed for a shorter time in the wound, but the differences were not significant. There was no difference in the length of hospital stay, time to stitch removal, and number of dressing changes. More haematomas and wound infections occurred in the simple drain group while more seromas occurred in the suction drain group, but these were not significant. The suction drain was more difficult to manage and the cost was 15 times higher than the simple drainage system. Closed simple drains are not inferior to suction drains in mastectomy wounds and, considering the cost saving and simplicity of postoperative care, they are preferable to suction drains.

  16. The results of the electrochemical clearning of drainage waters

    Science.gov (United States)

    Kabannik, Vasilina; Saeva, Olga

    2010-05-01

    object represents very difficult chemical system not received. In this work the experimental researches on clearing acid drainage waters of the Belov Zink Plant from a lot of toxic elements during electrochemical with the active Al anode are resulted. For achievement of an object in view following experiment has been conducted. To a drainage solution in volume of 100 ml have added an aluminium foil (0,3 g weight). In an electrochemical line of activity Al stands more to the left of considered metals: K, Ca, Na, Mg, Al, Mn, Zn, Fe, Co, Ni, Pb, H, Cu, Ag, Pt, Au, i.e. possesses more negative potential. At interaction of metal aluminium with a solution, containing salt metals with less negative potential than aluminium, there will be a transition electones from aluminium to Ме +. Thus, there will be restoration Ме + and oxidation of aluminium: Меn+ + n ē → Me0, Al0 - 3ē→ Al3+. In seven day of experiment it is revealed, that the is bright-blue drainage solution has become colourless (рН=3.9), the plate was dissolved approximately half, at the bottom of a glass powder copper (0.5 g) has dropped out in a deposit. Owing to that Al-hydroxide start to drop out at рН a solution> 4, we could separate free filtering powder copper from a solution. At a following stage of experiment have besieged Al-hydroxide by means of neutralization of a solution by ammonia up to рН 7.5. Dropped out white flakes have separated from a solution by filtering. By results of experiment (a method of analysis ISP-IES), that after interaction with an aluminium foil in a solution there were 10 mg/l Cu and Pb metals have remained at the same level. It is possible to explain it to that copper and lead possess the greatest difference of potentials with aluminium. After neutralization at the second stage of experiment concentration of Al became at level MPC. Owing to co-precipitation on Al-hydroxide the amount of toxic elements Be, Se became comparable with MPC; for Fe, Cu - it is less MPC. In

  17. Low Voltage Power Supply Incorporating Ceramic Transformer

    CERN Document Server

    Imori, M

    2007-01-01

    A low voltage power supply provides the regulated output voltage of 1 V from the supply voltage around 48 V. The low voltage power supply incorporates a ceramic transformer which utilizes piezoelectric effect to convert voltage. The ceramic transformer isolates the secondary from the primary, thus providing the ground isolation between the supply and the output voltages. The ceramic transformer takes the place of the conventional magnetic transformer. The ceramic transformer is constructed from a ceramic bar and does not include any magnetic material. So the low voltage power supply can operate under a magnetic field. The output voltage is stabilized by feedback. A feedback loop consists of an error amplifier, a voltage controlled oscillator and a driver circuit. The amplitude ratio of the transformer has dependence on the frequency, which is utilized to stabilize the output voltage. The low voltage power supply is investigated on the analogy of the high voltage power supply similarly incorporating the cerami...

  18. Modular High Voltage Power Supply

    Energy Technology Data Exchange (ETDEWEB)

    Newell, Matthew R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-18

    The goal of this project is to develop a modular high voltage power supply that will meet the needs of safeguards applications and provide a modular plug and play supply for use with standard electronic racks.

  19. Determination of appropriate DC voltage for switched mode power supply (SMPS) loads

    Science.gov (United States)

    Setiawan, Eko Adhi; Setiawan, Aiman; Purnomo, Andri; Djamal, Muchlishah Hadi

    2017-03-01

    Nowadays, most of modern and efficient household electronic devices operated based on Switched Mode Power Supply (SMPS) technology which convert AC voltage from the grid to DC voltage. Based on theory and experiment, SMPS loads could be supplied by DC voltage. However, the DC voltage rating to energize electronic home appliances is not standardized yet. This paper proposed certain method to determine appropriate DC voltage, and investigated comparison of SMPS power consumption which is supplied from AC and DC voltage. To determine the appropriate DC voltage, lux value of several lamps which have same specification energized by using AC voltage and the results is using as reference. Then, the lamps were supplied by various DC voltage to obtain the trends of the lux value to the applied DC voltage. After that, by using the trends and the reference lux value, the appropriate DC voltage can be determined. Furthermore, the power consumption on home appliances such as mobile phone, laptop and personal computer by using AC voltage and the appropriate DC voltage were conducted. The results show that the total power consumption of AC system is higher than DC system. The total power (apparent power) consumed by the lamp, mobile phone and personal computer which operated in 220 VAC were 6.93 VA, 34.31 VA and 105.85 VA respectively. On the other hand, under 277 VDC the load consumption were 5.83 W, 19.11 W and 74.46 W respectively.

  20. Reliability criteria for voltage stability

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Carson W.; Silverstein, Brian L. [Bonneville Power Administration, Portland, OR (United States)

    1994-12-31

    In face of costs pressures, there is need to allocate scare resources more effectively in order to achieve voltage stability. This naturally leads to development of probabilistic criteria and notions of rick management. In this paper it is presented a discussion about criteria for long term voltage stability limited to the case in which the time frames are topically several minutes. (author) 14 refs., 1 fig.

  1. A Voltage Quality Detection Method

    DEFF Research Database (Denmark)

    Chen, Zhe; Wei, Mu

    2008-01-01

    This paper presents a voltage quality detection method based on a phase-locked loop (PLL) technique. The technique can detect the voltage magnitude and phase angle of each individual phase under both normal and fault power system conditions. The proposed method has the potential to evaluate vario...... power quality disturbances, such as interruptions, sags and imbalances. Simulation studies have been performed. The effectiveness of the proposed method has been demonstrated under the simulated typical power disturbances....

  2. Fluoroscopy guided percutaneous catheter drainage of pneumothorax in good mid-term patency with tube drainage

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ga Young; Oh, Joo Hyung; Yoon, Yup; Sung, Dong Wook [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1995-10-15

    To evaluate efficacy and the safety of percutaneous catheter drainage in patients with pneumothorax that is difficult to treat with closed thoracotomy. We retrospectively reviewed effectiveness of percutaneous catheter drainage (PCD) in 10 patients with pneumothorax. The catheter was inserted under fluoroscopic guidance. Seven patients had spontaneous pneumothorax caused by tuberculosis (n =4), reptured bullae (n = 2), and histiocytosis-X (n = 1). Three patients had iatrogenic pneumothorax caused by trauma (n = 1) and surgery (n = 2). All procedures were performed by modified Seldinger's method by using 8F-20F catheter. All catheter were inserted successfully. In 9 of 10 patients, the procedure was curative without further therapy. Duration of catheter insertion ranged from 1 day to 26 days. In the remaining 1 patient in whom multiple pneumothorax occurred after operation, catheter insertion was performed twice. Percutaneous catheter drainage under fluoroscopic guidance is effective and safe procedure for treatment of pneumothorax in patients with failed closed thoracotomy.

  3. Surfactant effect on drop coalescence and film drainage hydrodynamics

    Science.gov (United States)

    Weheliye, Weheliye; Chinaud, Maxime; Voulgaropoulos, Victor; Angeli, Panagiota

    2015-11-01

    Coalescence of a drop on an aqueous-organic interface is studied in two test geometries A rectangular acrylic vessel and a Hele-Shaw cell (two parallel plates placed 2mm apart) are investigated for the experiments. Time resolved Particle Image Velocimetry (PIV) measurements provide information on the hydrodynamics during the bouncing stage of the droplet and on the vortices generated at the bulk fluid after the droplet has coalesced. The velocity field inside the droplet during its coalescence is presented. By localizing the rupture point of the coalescence in the quasi two dimensional cell, the film drainage dynamics are discussed by acquiring its flow velocity by PIV measurements with a straddling camera. The effect of surface tension forces in the coalescence of the droplet is investigated by introducing surface active agents at various concentrations extending on both sides of the critical micelle concentration.

  4. VOLTAGE COMPENSATION USING ARTIFICIAL NEURAL NETWORK

    African Journals Online (AJOL)

    VOLTAGE COMPENSATION USING ARTIFICIAL NEURAL NETWORK: A CASE STUDY OF RUMUOLA DISTRIBUTION NETWORK. ... The artificial neural networks controller engaged to controlling the dynamic voltage ... Article Metrics.

  5. New zero voltage switching DC converter with flying capacitors

    Science.gov (United States)

    Lin, Bor-Ren; Shiau, Tung-Yuan

    2016-04-01

    A new soft switching converter is presented for medium power applications. Two full-bridge converters are connected in series at high voltage side in order to limit the voltage stress of power switches at Vin/2. Therefore, power metal-oxide-semiconductor field-effect transistors (MOSFETs) with 600 V voltage rating can be adopted for 1200 V input voltage applications. In order to balance two input split capacitor voltages in every switching cycle, two flying capacitors are connected on the AC side of two full-bridge converters. Phase-shift pulse-width modulation (PS-PWM) is adopted to regulate the output voltage. Based on the resonant behaviour by the output capacitance of MOSFETs and the resonant inductance, active MOSFETs can be turned on under zero voltage switching (ZVS) during the transition interval. Thus, the switching losses of power MOSFETs are reduced. Two full-bridge converters are used in the proposed circuit to share load current and reduce the current stress of passive and active components. The circuit analysis and design example of the prototype circuit are provided in detail and the performance of the proposed converter is verified by the experiments.

  6. Control Strategy and Experiment of High Voltage Ride Through for DFIG-based Wind Turbines%双馈风电机组高电压穿越控制策略与试验

    Institute of Scientific and Technical Information of China (English)

    李少林; 王伟胜; 王瑞明; 孙勇; 陈晨

    2016-01-01

    In research of frequent tripping of wind turbines under high voltage conditions , the requirements for high voltage ride through ( HVRT) of the main grid integration guide to wind power are introduced . A comparative analysis of electromagnetic transient characteristics of doubly‐fed induction generator (DFIG) based wind turbines is carried out under dip and voltage swell conditions , and the full control of the DFIG‐based wind turbines HVRT process is demonstrated if the voltage is less than 1 .3 nominal voltage . Then , a collaborative HVRT control strategy for DFIG‐based wind turbines based on main controller and the convertor is proposed , which is implemented just by software improvement without hardware modification , and avoids the adverse effect of Crowbar or Chopper protection action on the characteristics of HVRT . A 2 MW DFIG‐based wind turbines model for HVRT research is built in MATLAB/Simulink , and the HVRT process of DFIG‐based wind turbines is simulated . The field test is carried out on a 2 MW DFIG‐based wind turbines by high voltage generator for the first time . The simulation and experimental results support the theoretical analysis and verifies the effectiveness of the proposed control strategy .%针对风电的高电压脱网问题,介绍了主要风电并网导则对高电压穿越的要求,对比分析了双馈风电机组低电压和高电压的电磁暂态特性,论证了双馈风电机组1.3倍额定电压的高电压穿越过程全程可控的可行性。提出了一种基于双馈变流器动态无功控制的高电压穿越控制策略和风电机组主控系统与变流器协同控制完成高电压穿越的实现方法,避免了 Crowbar 或 Chopper 保护动作对高电压穿越特性的不利影响。在 MATLAB/Simulink 中建立了2 MW 双馈风电机组高电压穿越仿真模型,实现了高电压穿越全过程仿真;利用高电压发生装置,在2 MW 双馈风电机组上进行了高电压穿越

  7. Recovery of water from acid mine drainage

    CSIR Research Space (South Africa)

    Mulopo, J

    2010-10-01

    Full Text Available acid mine drainage J Mulopo, SR Motaung , M Mashego and M Moalusi Natural Resources and the Environment, CSIR, P O Box 395, Pretoria, 0001, South Africa ConClusion The optimal region for the operation and design of a sulphate removal reactor... operating conditions results in a process with somehow large excess feed. Hence, one should not optimize the reactor configuration independently of the process in which the reactor is going to be used. Figure 1: Rate of Sulphate Removal at 25o...

  8. Ultrasound-guided drainage of deep pelvic abscesses

    DEFF Research Database (Denmark)

    Lorentzen, Torben; Nolsøe, Christian; Skjoldbye, Bjørn

    2011-01-01

    The aim of this study was to demonstrate and evaluate the ultrasound-guided drainage of deep pelvic abscesses in which transabdominal percutaneous access could not be performed because of overlying structures. A retrospective analysis of 32 consecutive patients with 33 deep pelvic abscesses...... (median diameter 7 cm), 19 were treated with catheter drainage and 18 of these cases resulted in favorable clinical outcomes. Of the smaller abscesses (median diameter 4 cm), 14 were treated with needle drainage. In two of these cases, follow-up US showed that a repeat puncture and drainage was necessary...... and the subsequent in-dwelling catheter period, there were no serious complications related to the drainage procedures. We conclude that ultrasound-guided transrectal, transvaginal, transperineal and transgluteal drainage of deep pelvic abscesses are safe and effective treatment approaches. Based on our findings...

  9. Inductive voltage adder (IVA) for submillimeter radius electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E. [and others

    1996-12-31

    The authors have already demonstrated the utility of inductive voltage adder accelerators for production of small-size electron beams. In this approach, the inductive voltage adder drives a magnetically immersed foilless diode to produce high-energy (10--20 MeV), high-brightness pencil electron beams. This concept was first demonstrated with the successful experiments which converted the linear induction accelerator RADLAC II into an IVA fitted with a small 1-cm radius cathode magnetically immersed foilless diode (RADLAC II/SMILE). They present here first validations of extending this idea to mm-scale electron beams using the SABRE and HERMES-III inductive voltage adders as test beds. The SABRE experiments are already completed and have produced 30-kA, 9-MeV electron beams with envelope diameter of 1.5-mm FWHM. The HERMES-III experiments are currently underway.

  10. Treatment of emulsified oils by electrocoagulation: pulsed voltage applications.

    Science.gov (United States)

    Genc, Ayten; Bakirci, Busra

    2015-01-01

    The effect of pulsed voltage application on energy consumption during electrocoagulation was investigated. Three voltage profiles having the same arithmetic average with respect to time were applied to the electrodes. The specific energy consumption for these profiles were evaluated and analyzed together with oil removal efficiencies. The effects of applied voltages, electrode materials, electrode configurations, and pH on oil removal efficiency were determined. Electrocoagulation experiments were performed by using synthetic and real wastewater samples. The pulsed voltages saved energy during the electrocoagulation process. In continuous operation, energy saving was as high as 48%. Aluminum electrodes used for the treatment of emulsified oils resulted in higher oil removal efficiencies in comparison with stainless steel and iron electrodes. When the electrodes gap was less than 1 cm, higher oil removal efficiencies were obtained. The highest oil removal efficiencies were 95% and 35% for the batch and continuous operating modes, respectively.

  11. Electrode voltage fall and total voltage of a transient arc

    Science.gov (United States)

    Valensi, F.; Ratovoson, L.; Razafinimanana, M.; Masquère, M.; Freton, P.; Gleizes, A.

    2016-06-01

    This paper deals with an experimental study of the components of a transient arc total voltage with duration of a few tens of ms and a current peak close to 1000 A. The cathode tip is made of graphite whereas the flat anode is made either of copper or of graphite; the electrodes gap is a few mm. The analysis of the electrical parameters is supported and validated by fast imaging and by two models: the first one is a 2D physical model of the arc allowing to calculate both the plasma temperature field and the arc voltage; the second model is able to estimate the transient heating of the graphite electrode. The main aim of the study was to detect the possible change of the cathode voltage fall (CVF) during the first instants of the arc. Indeed it is expected that during the first ms the graphite cathode is rather cool and the main mechanism of the electron emission should be the field effect emission, whereas after several tens of ms the cathode is strongly heated and thermionic emission should be predominant. We have observed some change in the apparent CVF but we have shown that this apparent change can be attributed to the variation of the solid cathode resistance. On the other hand, the possible change of CVF corresponding to the transition between a ‘cold’ and a ‘hot’ cathode should be weak and could not be characterized considering our measurement uncertainty of about 2 V. The arc column voltage (ACV) was estimated by subtracting the electrode voltage fall from the total arc voltage. The experimental transient evolution of the ACV is in very good agreement with the theoretical variation predicted by the model, showing the good ability of the model to study this kind of transient arc.

  12. Unbalanced Voltage Compensation in Low Voltage Residential AC Grids

    DEFF Research Database (Denmark)

    Trintis, Ionut; Douglass, Philip; Munk-Nielsen, Stig

    2016-01-01

    This paper describes the design and test of a control algorithm for active front-end rectifiers that draw power from a residential AC grid to feed heat pump loads. The control algorithm is able to control the phase to neutral or phase to phase RMS voltages at the point of common coupling....... The voltage control was evaluated with either active or reactive independent phase load current control. The control performance in field operation in a residential grid situated in Bornholm, Denmark was investigated for different use cases....

  13. Preoperative biliary drainage for periampullary tumors causing obstructive jaundice; DRainage vs. (direct) OPeration (DROP-trial)

    NARCIS (Netherlands)

    N.A. van der Gaag (Niels); S.M.M. de Castro (Steve); E.A.J. Rauws (Erik); M.J. Bruno (Marco); C.H.J. van Eijck (Casper); E.J. Kuipers (Ernst); J.J.G.M. Gerritsen (Josephus); J.P. Rutten (Joost Paul); J.W. Greve; E.J. Hesselink (Eric); J.H. Klinkenbijl (Jean); I.H.M.B. Rinkes; D. Boerma (Djamila); B.A. Bonsing (Bert); C.J. van Laarhoven (Cees); F.J. Kubben; E. van der Harst (Erwin); M.N. Sosef (Meindert); K. Bosscha (Koop); I.H.J.T. de Hingh (Ignace); L. Th de Wit (Laurens); O.M. van Delden (Otto); O.R.C. Busch (Olivier); T.M. van Gulik (Thomas); P.M.M. Bossuyt (Patrick); D.J. Gouma (Dirk)

    2007-01-01

    textabstractBackground. Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to im

  14. Comparing twist-drill drainage with burr hole drainage for chronic subdural hematoma

    Directory of Open Access Journals (Sweden)

    LIN Xin

    2011-06-01

    Full Text Available 【Abstract】Objective: The surgical management of chronic subdural hematoma (CSDH is still a controver- sial issue, and a standard therapy has not been established because of the unclear pathogenic mechanisms in CSDH. The intention of this paper is to find a simple and efficient surgical procedure for CSDH. Methods: A retrospective study of 448 patients with CSDH by surgical treatment during 2005 to 2009 was con- ducted in order to compare the efficiency between two dif- ferent primary surgical methods, i.e. twist-drill drainage with- out irrigation in Group A (n=178 and one burr-hole with irrigation in Group B (n=270. The results were statistically analyzed. Results: The reoperation rates in Group A and Group B were 7.9% and 11.9% respectively. The good outcome rate was 88.8% and 75.5%, the complication was 7.9% and 20.7% in Group A and Group B, respectively. Conclusions: The burr-hole drainage with irrigation of the hematoma cavity is not beneficial to the outcome and prognosis. Irrigation is not important in the surgical treat- ment for CSDH. Thus in initial treatment, twist-drill drainage without irrigation of the hematoma cavity is recommended because it is relatively safe, time-saving and cost-effective. Key words: Hematoma, subdural; Brain injury, chronic; Drainage

  15. Reuse of drainage water model : calculation method of drainage water and watertable depth

    NARCIS (Netherlands)

    Roest, C.W.J.; Rijtema, P.E.; Abdel Khalik, M.A.

    1986-01-01

    The main objective of the project is to assist the Ministry of Irrigation in Egypt in the planning of future watermanagement strategies incorporating reuse of drainage water practices. In order to achieve this main objective a comprehensive measurement programme has been initiated and a mathematical

  16. SVPWM Technique with Varying DC-Link Voltage for Common Mode Voltage Reduction in a Matrix Converter and Analytical Estimation of its Output Voltage Distortion

    Science.gov (United States)

    Padhee, Varsha

    converter. This conceivably aids the sizing and design of output passive filters. An analytical estimation method has been presented to achieve this purpose for am IMC. Knowledge of the fundamental component in output voltage can be utilized to calculate its Total Harmonic Distortion (THD). The effectiveness of the proposed SVPWM algorithms and the analytical estimation technique is substantiated by simulations in MATLAB / Simulink and experiments on a laboratory prototype of the IMC. Proper comparison plots have been provided to contrast the performance of the proposed methods with the conventional SVPWM method. The behavior of output voltage distortion and CMV with variation in operating parameters like modulation index and output frequency has also been analyzed.

  17. Pancreatic tissue fluid pressure during drainage operations for chronic pancreatitis

    DEFF Research Database (Denmark)

    Ebbehøj, N; Borly, L; Madsen, P

    1990-01-01

    Pancreatic tissue fluid pressure was measured in 10 patients undergoing drainage operations for painful chronic pancreatitis. The pressure was measured by the needle technique in the three anatomic regions of the pancreas before and at different stages of the drainage procedure, and the results...... a decrease in pancreatic tissue fluid pressure during drainage operations for pain in chronic pancreatitis. Regional pressure decrease were apparently unrelated to ERCP findings....

  18. Pancreatic tissue fluid pressure during drainage operations for chronic pancreatitis

    DEFF Research Database (Denmark)

    Ebbehøj, N; Borly, L; Madsen, P

    1990-01-01

    Pancreatic tissue fluid pressure was measured in 10 patients undergoing drainage operations for painful chronic pancreatitis. The pressure was measured by the needle technique in the three anatomic regions of the pancreas before and at different stages of the drainage procedure, and the results...... a decrease in pancreatic tissue fluid pressure during drainage operations for pain in chronic pancreatitis. Regional pressure decrease were apparently unrelated to ERCP findings....

  19. [Fabrication of improved multi-slit equipment to obtain the input-output characteristics of computed radiography systems: correction of the heel effect, and application to high tube-voltage experiments].

    Science.gov (United States)

    Maehata, Itsumi; Hayashi, Hiroaki; Takegami, Kazuki; Ujita, Syohei; Kimoto, Natsumi; Konishi, Yuki; Fukuda, Ikuma

    2014-09-01

    Multi-slit equipment is a new experimental apparatus that can measure the input-output characteristics of a CR (computed radiography) system with limited influence of the fading effect. Kimoto et al. recently proposed a new type of multi-slit apparatus in which the multi-slit setup, the insertion region of the phosphor plate, and plate shielding are integrated to create a single handy-type item (an all-in-one type multi-slit apparatus). However, some problems remained unsolved. The aims of this study were to devise a setup for application to high tube voltage conditions, and to improve the all-in-one type multi-slit equipment so as to correct the heel effect. We examined the capabilities of our improved multi-slit equipment using diagnostic X-ray apparatus and found that it can obtain input-output characteristics with 5% accuracy for tube voltages of 40-140 kV and SID (source to image receptor distances) of 50-200 cm.

  20. Bioreactor for acid mine drainage control

    Science.gov (United States)

    Zaluski, Marek H.; Manchester, Kenneth R.

    2001-01-01

    A bioreactor for reacting an aqueous heavy metal and sulfate containing mine drainage solution with sulfate reducing bacteria to produce heavy metal sulfides and reduce the sulfuric acid content of the solution. The reactor is an elongated, horizontal trough defining an inlet section and a reaction section. An inlet manifold adjacent the inlet section distributes aqueous mine drainage solution into the inlet section for flow through the inlet section and reaction section. A sulfate reducing bacteria and bacteria nutrient composition in the inlet section provides sulfate reducing bacteria that with the sulfuric acid and heavy metals in the solution to form solid metal sulfides. The sulfate reducing bacteria and bacteria nutrient composition is retained in the cells of a honeycomb structure formed of cellular honeycomb panels mounted in the reactor inlet section. The honeycomb panels extend upwardly in the inlet section at an acute angle with respect to the horizontal. The cells defined in each panel are thereby offset with respect to the honeycomb cells in each adjacent panel in order to define a tortuous path for the flow of the aqueous solution.

  1. Development of a New Cascade Voltage-Doubler for Voltage Multiplication

    OpenAIRE

    Arash Toudeshki; Norman Mariun; Hashim Hizam; Noor Izzri Abdul Wahab

    2014-01-01

    For more than eight decades, cascade voltage-doubler circuits are used as a method to produce DC output voltage higher than the input voltage. In this paper, the topological developments of cascade voltage-doublers are reviewed. A new circuit configuration for cascade voltage-doubler is presented. This circuit can produce a higher value of the DC output voltage and better output quality compared to the conventional cascade voltage-doubler circuits, with the same number of stages.

  2. Low-Energy Real-Time OS Using Voltage Scheduling Algorithm for Variable Voltage Processors

    OpenAIRE

    Okuma, Takanori; Yasuura, Hiroto

    2001-01-01

    This paper presents a real-time OS based on $ mu $ITRON using proposed voltage scheduling algorithm for variable voltage processors which can vary supply voltage dynamically. The proposed voltage scheduling algorithms assign voltage level for each task dynamically in order to minimize energy consumption under timing constraints. Using the presented real-time OS, running tasks with low supply voltage leads to drastic energy reduction. In addition, the presented voltage scheduling algorithm is ...

  3. Simple buck/boost voltage regulator

    Science.gov (United States)

    Paulkovich, J.; Rodriguez, G. E.

    1980-01-01

    Circuit corrects low or high supply voltage, produces regulated output voltage. Circuit has fewer components because inductory/transformer combination and pulse-width modulator serve double duty. Regulator handles input voltage variation from as low as one half output voltage to as high as input transistor rating. Solar arrays, fuel cells, and thermionic generators might use this regulator.

  4. 30 CFR 18.47 - Voltage limitation.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Voltage limitation. 18.47 Section 18.47 Mineral... § 18.47 Voltage limitation. (a) A tool or switch held in the operator's hand or supported against his... particular voltage(s) are provided in the design and construction of the equipment, its wiring,...

  5. Cavity Voltage Phase Modulation MD

    CERN Document Server

    Mastoridis, Themistoklis; Molendijk, John; Timko, Helga; CERN. Geneva. ATS Department

    2016-01-01

    The LHC RF/LLRF system is currently configured for extremely stable RF voltage to minimize transient beam loading effects. The present scheme cannot be extended beyond nominal beam current since the demanded power would exceed the peak klystron power and lead to saturation. A new scheme has therefore been proposed: for beam currents above nominal (and possibly earlier), the cavity phase modulation by the beam will not be corrected (transient beam loading), but the strong RF feedback and One-Turn Delay feedback will still be active for loop and beam stability in physics. To achieve this, the voltage set point will be adapted for each bunch. The goal of this MD was to test a new algorithm that would adjust the voltage set point to achieve the cavity phase modulation that would minimize klystron forward power.

  6. Portable High Voltage Impulse Generator

    Directory of Open Access Journals (Sweden)

    S. Gómez

    2011-07-01

    Full Text Available This paper presents a portable high voltage impulse generator which was designed and built with insulation up to 20 kV. This design was based on previous work in which simulation software for standard waves was developed. Commercial components and low-cost components were used in this work; however, these particular elements are not generally used for high voltage applications. The impulse generators used in industry and laboratories are usually expensive; they are built to withstand extra high voltage and they are big, making them impossible to transport. The proposed generator is portable, thereby allowing tests to be made on devices that cannot be moved from their location. The results obtained with the proposed impulse generator were satisfactory in terms of time and waveforms compared to other commercial impulse generators and the standard impulse wave simulator.

  7. A low voltage CMOS low drop-out voltage regulator

    Science.gov (United States)

    Bakr, Salma Ali; Abbasi, Tanvir Ahmad; Abbasi, Mohammas Suhaib; Aldessouky, Mohamed Samir; Abbasi, Mohammad Usaid

    2009-05-01

    A low voltage implementation of a CMOS Low Drop-Out voltage regulator (LDO) is presented. The requirement of low voltage devices is crucial for portable devices that require extensive computations in a low power environment. The LDO is implemented in 90nm generic CMOS technology. It generates a fixed 0.8V from a 2.5V supply which on discharging goes to 1V. The buffer stage used is unity gain configured unbuffered OpAmp with rail-to-rail swing input stage. The simulation result shows that the implemented circuit provides load regulation of 0.004%/mA and line regulation of -11.09mV/V. The LDO provides full load transient response with a settling time of 5.2μs. Further, the dropout voltage is 200mV and the quiescent current through the pass transistor (Iload=0) is 20μA. The total power consumption of this LDO (excluding bandgap reference) is only 80μW.

  8. Implementation of Dynamic Voltage Restorer for Mitigation of Voltage Sag

    Directory of Open Access Journals (Sweden)

    K.Vinod Kumar

    2013-07-01

    Full Text Available Power quality is one of major concerns in the present. It has become important, especially with the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply. The dynamic voltage restorer (DVR is one of the modern devices used in distribution systems to improve the power quality. In this paper, emergency control in distribution systems is discussed by using the proposed multifunctional DVR control strategy.Also, themultiloop controller using the Posicast and P+Resonant controllers is proposed in order to improve the transient response and eliminate the steady state error in DVR response,respectively.The proposed process is applied to some riots in load voltage effected by induction motors starting, and a three-phase short circuit fault. The three-phase short circuits, and the large induction motors are suddenly started then voltage sags areoccurred.The innovation here is that by using the Multifunctional Dynamic Voltage Restorer, improve the power quality in distribution side. Simulation results show the capability of the DVR to control the emergency conditions of the distribution systems by using MATLAB/Simulink software.

  9. The high voltage homopolar generator

    Science.gov (United States)

    Price, J. H.; Gully, J. H.; Driga, M. D.

    1986-11-01

    System and component design features of proposed high voltage homopolar generator (HVHPG) are described. The system is to have an open circuit voltage of 500 V, a peak output current of 500 kA, 3.25 MJ of stored inertial energy and possess an average magnetic-flux density of 5 T. Stator assembly components are discussed, including the stator, mount structure, hydrostatic bearings, main and motoring brushgears and rotor. Planned operational procedures such as monitoring the rotor to full speed and operation with a superconducting field coil are delineated.

  10. Instability analysis on drainage flow over a complex terrain

    Science.gov (United States)

    Yi, C.

    2007-12-01

    The turbulent transport processes that occur within canopies are extremely complex and have not been accurately represented in past models, especially for ecosystems with hilly or mountainous terrain. The stability analysis on the terrain-induced canopy flows is the key to understanding the introduction of pollutants into the atmosphere and the transfer of water from soil and vegetation to the atmosphere. We applied the Computational Fluid Dynamics (CFD) approach to forest environments to simulate airflows within and above canopy. The results of the CFD experiments show three different dynamic regimes of topographic drainage flow that were simulated under different thermal-dynamic conditions: (1) Cold inflow induces drainage flow in the lower part of canopy and strong stratification of airflows within entire canopy; additionally, the model predicts that there is a super stable layer around the maximum LAD level, which is consistent with our canopy flow theory. This super stable layer minimizes vertical land-atmosphere exchange around the middle level of canopy. (2) Warm inflow causes the rapid flushing of land-atmosphere exchange at the location where two opposite air motions meet, this is called the 'chimney phenomenon'. (3) The oscillation of canopy flow occurs as the inflow temperature is close to the environmental temperature. These CFD simulations are based on fully derived thermal and fluid dynamic equations. In order to clearly understand the physical mechanisms for the transfer between the different dynamic regimes, I utilized the nonlinear dynamics approach to derive the analytical instability conditions of terrain-induced flows from the simplified thermal-hydro-mechanical equations. The analytical derivations are tested against the CFD simulations. These analytical conditions provide a better understanding of transport problem in ecosystem- atmosphere exchanges of water, carbon dioxide, and energy over complex terrain.

  11. Resilient architecture design for voltage variation

    CERN Document Server

    Reddi, Vijay Janapa

    2013-01-01

    Shrinking feature size and diminishing supply voltage are making circuits sensitive to supply voltage fluctuations within the microprocessor, caused by normal workload activity changes. If left unattended, voltage fluctuations can lead to timing violations or even transistor lifetime issues that degrade processor robustness. Mechanisms that learn to tolerate, avoid, and eliminate voltage fluctuations based on program and microarchitectural events can help steer the processor clear of danger, thus enabling tighter voltage margins that improve performance or lower power consumption. We describe

  12. Inventory of drainage wells and potential sources of contaminants to drainage-well inflow in Southwest Orlando, Orange County, Florida

    Science.gov (United States)

    Taylor, George Fred

    1993-01-01

    Potential sources of contaminants that could pose a threat to drainage-well inflow and to water in the Floridan aquifer system in southwest Orlando, Florida, were studied between October and December 1990. Drainage wells and public-supply wells were inventoried in a 14-square-mile area, and available data on land use and activities within each drainage well basin were tabulated. Three public-supply wells (tapping the Lower Floridan aquifer) and 38 drainage wells (open to the Upper Floridan aquifer) were located in 17 drainage basins within the study area. The primary sources of drainage-well inflow are lake overflow, street runoff, seepage from the surficial aquifer system, and process-wastewater disposal. Drainage-well inflow from a variety of ares, including resi- dential, commercial, undeveloped, paved, and industrial areas, are potential sources of con- taminants. The four general types of possible contaminants to drainage-well inflow are inorganic chemicals, organic compounds, turbidity, and microbiological contaminants. Potential contami- nant sources include plant nurseries, citrus groves, parking lots, plating companies, auto- motive repair shops, and most commonly, lake- overflow water. Drainage wells provide a pathway for contaminants to enter the Upper Floridan aquifer and there is a potential for contaminants to move downward from the Upper Floridan to the Lower Floridan aquifer.

  13. Is ultrasonography-guided drainage a safe and effective alternative to incision and drainage for deep neck space abscesses?

    Science.gov (United States)

    Dabirmoghaddam, P; Mohseni, A; Navvabi, Z; Sharifi, A; Bastaninezhad, S; Safaei, A

    2017-03-01

    Deep neck space abscesses are common head and neck surgery emergencies. Traditionally, surgical incision and drainage has been the main treatment for deep neck abscesses. Recently, it has been suggested that ultrasound-guided drainage of neck abscesses can be an effective and less invasive alternative to incision and drainage. Patients with deep neck space abscesses referred to the emergency department of Amiralam Hospital were assessed and enrolled to the study if they met the inclusion criteria. Patients were randomly assigned to incision and drainage or ultrasound-guided drainage groups using sealed envelopes. Sixty patients were evaluated, with 30 patients in each group. There was a significant difference (p < 0.001) in mean length of hospital stay between patients who underwent ultrasound-guided drainage (5.47 days) and those who underwent incision and drainage (9.70 days). Ultrasound-guided drainage is an effective and safe procedure, leading to shorter hospital stay, and thus may be a suitable alternative to incision and drainage of deep neck abscesses.

  14. A Half-Bridge Voltage Balancer with New Controller for Bipolar DC Distribution Systems

    Directory of Open Access Journals (Sweden)

    Byung-Moon Han

    2016-03-01

    Full Text Available This paper proposes a half-bridge voltage balancer with a new controller for bipolar DC distribution systems. The proposed control scheme consists of two cascaded Proportional Integral (PI controls rather than one PI control for balancing the pole voltage. In order to confirm the excellence of voltage balancing performance, a typical bipolar DC distribution system including a half-bridge voltage balancer with proposed controller was analyzed by computer simulations. Experiments with a scaled prototype were also carried out to confirm the simulation results. The half-bridge voltage balancer with proposed controller shows better performance than the half-bridge voltage balancer with one PI control for balancing the pole voltage.

  15. VOLTAGE REGULATORS OF SYNCHRONOUS GENERATORS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-06-01

    Full Text Available Synchronous generators are the primary source of electrical power autonomous electrosupply systems, including backup systems. They are also used in a structure of rotating electricity converters and are widely used in renewable energy as part of wind power plants of small, mini and micro hydroelectric plants. Increasing the speed and the accuracy of the system of the voltage regulation of synchronous generators is possible due to the development of combined systems containing more stabilizers. The article illustrates the functional schemes of circuit voltage stabilizers and frequency synchronous generators (with electromagnetic excitation and permanent magnet excitation and describes the features of their work, including two and three-aggregate rotating converters of electricity used in uninterruptible power supply systems. To improve the technical characteristics of the system of stabilization we have proposed functional solutions for stabilizers of synchronous generators made on the base of direct frequency converters and using a transformer with a rotating magnetic field. To improve the reliability of and to improve the operational characteristics of the autonomous independent sources of electricity we suggest creating the main functional blocks and the elements of the stabilization system in a modular way. The functional circuit solutions of voltage regulators of synchronous generators and the characteristics of their work considered in the article, are able to improve the efficiency of pre-design work in the development of new technical solutions for stabilizing the voltage and the frequency in synchronous generators of electrosupply autonomous systems

  16. Frequency-controlled voltage regulator

    Science.gov (United States)

    Mclyman, W. T.

    1980-01-01

    Converting input ac to higher frequency reduce size and weight and makes possible unique kind of regulation. Since conversion frequency is above range of human hearing, supply generated on audible noise. It also exploits highfrequency conversion features to regulate its output voltage in novel way. Circuit is inherently short-circuit proof.

  17. Free drainage of aqueous foams: Container shape effects on capillarity and vertical gradients

    Science.gov (United States)

    Saint-Jalmes, A.; Vera, M. U.; Durian, D. J.

    2000-06-01

    The standard drainage equation applies only to foam columns of constant cross-sectional area. Here, we generalize to include the effects of arbitrary container shape and develop an exact solution for an exponential, "Eiffel Tower", sample. This geometry largely eliminates vertical wetness gradients, and hence capillary effects, and should permit a clean test of dissipation mechanisms. Agreement with experiment is not achieved at late times, however, highlighting the importance of both boundary conditions and coarsening.

  18. Ultrasonography-guided drainage of tuberculous abscess in the retromammary region : a case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Mi; Choi, Seong Hoon; Yoon, Hyun Ki; Sung, Kyu Bo; Sohn, Byung Ho; Ahn, Sei Hyun; Gong, Gyung Yub [Ulsan Asan Medical Center, Ulsan (Korea, Republic of)

    1999-05-01

    We report our recent experience of successful ultrasonography-guided catheter drainage of a huge retromammary abscess in a 27-year-old female patient with pulmonary tuberculosis. For breast abscesses, the procedure can be used instead of surgery. Its merits are that it is easy and cost-effective, there is less scar formation, outpatient management may be possible, and in reported cases there has been no recurrence.

  19. High-voltage pulsed generator for dynamic fragmentation of rocks.

    Science.gov (United States)

    Kovalchuk, B M; Kharlov, A V; Vizir, V A; Kumpyak, V V; Zorin, V B; Kiselev, V N

    2010-10-01

    A portable high-voltage (HV) pulsed generator has been designed for rock fragmentation experiments. The generator can be used also for other technological applications. The installation consists of low voltage block, HV block, coaxial transmission line, fragmentation chamber, and control system block. Low voltage block of the generator, consisting of a primary capacitor bank (300 μF) and a thyristor switch, stores pulse energy and transfers it to the HV block. The primary capacitor bank stores energy of 600 J at the maximum charging voltage of 2 kV. HV block includes HV pulsed step up transformer, HV capacitive storage, and two electrode gas switch. The following technical parameters of the generator were achieved: output voltage up to 300 kV, voltage rise time of ∼50 ns, current amplitude of ∼6 kA with the 40 Ω active load, and ∼20 kA in a rock fragmentation regime (with discharge in a rock-water mixture). Typical operation regime is a burst of 1000 pulses with a frequency of 10 Hz. The operation process can be controlled within a wide range of parameters. The entire installation (generator, transmission line, treatment chamber, and measuring probes) is designed like a continuous Faraday's cage (complete shielding) to exclude external electromagnetic perturbations.

  20. Exact solutions for nonlinear foam drainage equation

    Science.gov (United States)

    Zayed, E. M. E.; Al-Nowehy, Abdul-Ghani

    2016-09-01

    In this paper, the modified simple equation method, the exp-function method, the soliton ansatz method, the Riccati equation expansion method and the ( G^' }/G) -expansion method are used to construct exact solutions with parameters of the nonlinear foam drainage equation. When these parameters are taken to be special values, the solitary wave solutions and the trigonometric function solutions are derived from the exact solutions. The obtained results confirm that the proposed methods are efficient techniques for analytic treatments of a wide variety of nonlinear partial differential equations in mathematical physics. We compare our results together with each other yielding from these integration tools. Also, our results have been compared with the well-known results of others.

  1. Exact solutions for nonlinear foam drainage equation

    Science.gov (United States)

    Zayed, E. M. E.; Al-Nowehy, Abdul-Ghani

    2017-02-01

    In this paper, the modified simple equation method, the exp-function method, the soliton ansatz method, the Riccati equation expansion method and the ( G^' }/G)-expansion method are used to construct exact solutions with parameters of the nonlinear foam drainage equation. When these parameters are taken to be special values, the solitary wave solutions and the trigonometric function solutions are derived from the exact solutions. The obtained results confirm that the proposed methods are efficient techniques for analytic treatments of a wide variety of nonlinear partial differential equations in mathematical physics. We compare our results together with each other yielding from these integration tools. Also, our results have been compared with the well-known results of others.

  2. Integrated urban drainage, status and perspectives

    DEFF Research Database (Denmark)

    Harremoës, Poul

    2002-01-01

    This paper summarises the status of urban storm drainage as an integrated professional discipline, including the management-policy interface, by which the goals of society are implemented. The paper assesses the development of the discipline since the INTERURBA conference in 1992 and includes...... with a significant conservatism in the business. However, significant integrated analyses have been reported. Most of them deal with the sewer system and the treatment plant, while few incorporate the receiving water as anything but the object of the loads to be minimised by engineering measures up-stream. Important...... measures are local infiltration, source control, storage basins, local treatment and real time control. New paradigms have been introduced: risk of pollution due to system failure, technology for water reuse, sustainability, new architecture and greener up-stream solutions as opposed to down...

  3. Integrated urban drainage, status and perspectives

    DEFF Research Database (Denmark)

    Harremoës, Poul

    2002-01-01

    with a significant conservatism in the business. However, significant integrated analyses have been reported. Most of them deal with the sewer system and the treatment plant, while few incorporate the receiving water as anything but the object of the loads to be minimised by engineering measures up-stream. Important...... aspects of the papers presented at the INTERURBA-II conference in 2001 and the discussions during the conference. Tools for integrated analysis have been developed, but there is less implementation than could be expected. That is due to lack of adequate knowledge about important mechanisms, coupled......This paper summarises the status of urban storm drainage as an integrated professional discipline, including the management-policy interface, by which the goals of society are implemented. The paper assesses the development of the discipline since the INTERURBA conference in 1992 and includes...

  4. Vertical Analysis of Martian Drainage Basins

    Science.gov (United States)

    Stepinski, T. F.; OHara, W. J.

    2003-01-01

    We have performed a vertical analysis of drainage basins on Mars that were computationally extracted from DEMs based on the MOLA data. Longitudinal profiles of main streams are calculated and the slope-area relation is established for 20 basins coming from assorted martian locations. An identical analysis is done for 19 terrestrial river basins. Our results show that, in comparison to terrestrial basins, martian basins have more linear longitudinal profiles, more frequent existence of knickpoints, predominance of asymmetric location of the main stream in the basin, and smaller values of concavity exponent. This suggests a limited role for surface runoff on the global scale. However, two basins extracted from the slopes of martian volcanoes show a strong similarity to terrestrial basins, indicating a possible local role for the process of surface runoff.

  5. Ecology and management of agricultural drainage ditches: a literature review

    Science.gov (United States)

    Agricultural drainage ditches are headwater streams that have been modified or constructed for agricultural drainage, and are often used in conjunction with tile drains. These modified streams are a common landscape feature in Ohio, and constitute 25% of stream habitat within the state. Management o...

  6. A synthesis and comparative evaluation of drainage water management

    Science.gov (United States)

    Viable large-scale crop production in the United States requires artificial drainage in humid and poorly drained agricultural regions. Excess water removal is generally achieved by installing tile drains that export water to open ditches that eventually flow into streams. Drainage water management...

  7. 49 CFR 192.189 - Vaults: Drainage and waterproofing.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Vaults: Drainage and waterproofing. 192.189 Section 192.189 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Components § 192.189 Vaults: Drainage and waterproofing. (a) Each vault must be designed so as to...

  8. 7 CFR 1924.108 - Grading and drainage.

    Science.gov (United States)

    2010-01-01

    .... In questionable or unsurveyed areas, the applicant or developer will provide an engineering report... affect the structure and show proposed solutions. Grading will promote drainage of surface water away from buildings and foundations, minimize earth settlement and erosion, and assure that drainage...

  9. Voltage-gated Proton Channels

    Science.gov (United States)

    DeCoursey, Thomas E.

    2014-01-01

    Voltage-gated proton channels, HV1, have vaulted from the realm of the esoteric into the forefront of a central question facing ion channel biophysicists, namely the mechanism by which voltage-dependent gating occurs. This transformation is the result of several factors. Identification of the gene in 2006 revealed that proton channels are homologues of the voltage-sensing domain of most other voltage-gated ion channels. Unique, or at least eccentric, properties of proton channels include dimeric architecture with dual conduction pathways, perfect proton selectivity, a single-channel conductance ~103 smaller than most ion channels, voltage-dependent gating that is strongly modulated by the pH gradient, ΔpH, and potent inhibition by Zn2+ (in many species) but an absence of other potent inhibitors. The recent identification of HV1 in three unicellular marine plankton species has dramatically expanded the phylogenetic family tree. Interest in proton channels in their own right has increased as important physiological roles have been identified in many cells. Proton channels trigger the bioluminescent flash of dinoflagellates, facilitate calcification by coccolithophores, regulate pH-dependent processes in eggs and sperm during fertilization, secrete acid to control the pH of airway fluids, facilitate histamine secretion by basophils, and play a signaling role in facilitating B-cell receptor mediated responses in B lymphocytes. The most elaborate and best-established functions occur in phagocytes, where proton channels optimize the activity of NADPH oxidase, an important producer of reactive oxygen species. Proton efflux mediated by HV1 balances the charge translocated across the membrane by electrons through NADPH oxidase, minimizes changes in cytoplasmic and phagosomal pH, limits osmotic swelling of the phagosome, and provides substrate H+ for the production of H2O2 and HOCl, reactive oxygen species crucial to killing pathogens. PMID:23798303

  10. Conceptual design report for site drainage control

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, M.R.

    1996-07-01

    The Mound Plant (Mound), located in Miamisburg, Ohio, is a Department of Energy (DOE) development and production facility performing support work for DOE`s weapons and energy-related programs. EG&G Mound Applied Technologies, Inc. (EG&G) is the Operating Contractor (OC) for this Government-Owned, Contractor-Operated (GOCO) facility. The work performed at Mound emphasizes nuclear energy and explosives technology. Mound is currently implementing an Environmental, Safety & Health (ES&H) Upgrades Program designed to protect its employees, the public, and the environment from adverse effects caused by facility activities. The first project of this multiphase program is now in the final stages of construction, and the second project is currently under design. Four additional projects, one of which is presented in this report, are in the conceptual design stage. At Mound, 22 soil zones have become contaminated with radioactive material. These zones cover approximately 20 percent of the total area of developed property at the site. During a storm event, the rainwater washes contaminated soil from these zones into the storm sewer system. These radioactive contaminants may then be discharged along with the stormwater into the Great Miami River via the Miami Erie Canal. This conceptual design report (CDR), Site Drainage Control, the fourth project in the ES&H program, describes a project that will provide improvements and much needed repairs to inadequate and deteriorating portions of the storm drainage system on the developed property. The project also will provide a stormwater retention facility capable of storing the stormwater runoff, from the developed property, resulting from a 100-year storm event. These improvements will permit the effective control and monitoring of stormwater to prevent the spread of radioactive contaminants from contaminated soil zones and will provide a means to collect and contain accidental spills of hazardous substances.

  11. In-situ treatment of mine drainage water using porous reactive walls

    Energy Technology Data Exchange (ETDEWEB)

    Blowes, D.W.; Ptacek, C.J.; Waybrant, K.R.; Bain, J.G. [University of Waterloo, Waterloo, ON (Canada). Waterloo Centre for Groundwater Research

    1995-01-01

    The purpose is to describe research on porous reactive walls, which are installed in the path of plumes of ground water from tailings, to determine their suitability for prevention and remediation of acid mine drainage and dissolved metals release. The method involves removal of a portion of the aquifer in the ground water plume path and its replacement by a permeable reactive mixture. Experiments under way and preliminary results are described for laboratory batch and column experiments and for a small scale field experiment using reactive walls containing organic carbon and sulphate-reducing bacteria. The results suggest that the method is effective and economically viable. 8 refs., 3 figs.

  12. Drainage feature about coalbed methane wells in different hydrogeological conditions in Fanzhuaug area

    Institute of Scientific and Technical Information of China (English)

    NI Xiao-ming; LIN Ran; WANG Yan-bin

    2012-01-01

    It is aa important guarantee to enhance the production of coalbed methane (CBM) and reduce the project investment by finding out the drainage feature about CBM wells in different hydrogeological conditions.Based on the CBM exploration and development data on the Fanzhuang block in southeast Qinshui Basin and combined with the seepage principle and lithology on the roof and the bottom coalbed,the mathematical model of integrated permeability was established.By permeability experiments of the different lithologies on the roof and the floor within the 20 m range combined with the log curves,the integrated permeability of different lithological combinations were obtained.The starting pressure gradient and permeability of the roof and the floor for different lithologies was tested by "differential pressure-flow method".The relationships between the starting pressure gradient and the integrated permeability were obtained.The critical distance of limestone water penetrating into coal reservoirs was calculated.According to the drainage feature of CBM wells combined with the drainage data of some CBM wells,the results show that,when limestone water can penetrate into coal reservoirs,the daily water production is high and the daily gas production is low although there is no gas at the beginning of the drainage process,the CBM wells stop discharging water within 6 months after the gas began to come out,and the gas production is steadily improved.When limestone water can not penetrate into coal reservoirs,the daily water production is low and the daily gas production is high at the beginning of the drainage process,and it almost stops discharging water after some time when the gas come out,the daily gas production increases,and the cumulative water production is much lower.

  13. Acid drainage from coal mining: Effect on paddy soil and productivity of rice.

    Science.gov (United States)

    Choudhury, Burhan U; Malang, Akbar; Webster, Richard; Mohapatra, Kamal P; Verma, Bibhash C; Kumar, Manoj; Das, Anup; Islam, Mokidul; Hazarika, Samarendra

    2017-04-01

    Overburden and acid drainage from coal mining is transforming productive agricultural lands to unproductive wasteland in some parts of Northeast India. We have investigated the adverse effects of acid mine drainage on the soil of rice paddy and productivity by comparing them with non-mined land and abandoned paddy fields of Jaintia Hills in Northeast India. Pot experiments with a local rice cultivar (Myngoi) as test crop evaluated biological productivity of the contaminated soil. Contamination from overburden and acid mine drainage acidified the soil by 0.5 pH units, increased the exchangeable Al(3+) content 2-fold and its saturation on clay complexes by 53%. Available sulfur and extractable heavy metals, namely Fe, Mn and Cu increased several-fold in excess of critical limits, while the availability of phosphorus, potassium and zinc contents diminished by 32-62%. The grain yield of rice was 62% less from fields contaminated with acid mine drainage than from fields that have not suffered. Similarly, the amounts of vegetation, i.e. shoots and roots, in pots filled with soil from fields that received acid mine drainage were 59-68% less than from uncontaminated land (average shoot weight: 7.9±2.12gpot(-1); average root weight: 3.40±1.15gpot(-1)). Paddy fields recovered some of their productivity 4years after mining ceased. Step-wise multiple regression analysis affirmed that shoot weight in the pots and grain yield in field were significantly (ppots and grain yield in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Treatment of drainage solution from hydroponic greenhouse production with microalgae.

    Science.gov (United States)

    Hultberg, Malin; Carlsson, Anders S; Gustafsson, Susanne

    2013-05-01

    This study investigated treatment of the drainage solution from greenhouse production with microalgae, through inoculation with Chlorella vulgaris or through growth of the indigenous microalgal community. A significant reduction in nitrogen, between 34.7 and 73.7 mg L(-1), and particularly in phosphorus concentration, between 15.4 and 15.9 mg L(-1), was observed in drainage solution collected from commercial greenhouse production. The large reduction in nutrients was achieved through growth of the indigenous microalgal community i.e., without pre-treatment of the drainage solution or inoculation with the fast growing green microalgae C. vulgaris. Analysis of the fatty acid composition of the algal biomass revealed that compared with a standard growth medium for green algae, the drainage solution was inferior for lipid production. Despite the biorefinery concept being less promising, microalgae-based treatment of drainage solution from greenhouse production is still of interest considering the urgent need for phosphorus recycling.

  15. Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni; Wagirin Ruiz Paidin; Thaer N. N. Mahmoud; Daryl S. Sequeira; Amit P. Sharma

    2006-09-30

    three possible multiphase mechanisms at work, namely, Darcy-type displacement until gas breakthrough, gravity drainage after breakthrough and film-drainage in gas-invaded zones throughout the duration of the process. The partially-scaled physical model was used in a series of experiments to study the effects of wettability, gas-oil miscibility, secondary versus tertiary mode gas injection, and the presence of fractures on GAGD oil recovery. In addition to yielding recoveries of up to 80% IOIP, even in the immiscible gas injection mode, the partially-scaled physical model confirmed the positive influence of fractures and oil-wet characteristics in enhancing oil recoveries over those measured in the homogeneous (unfractured) water-wet models. An interesting observation was that a single logarithmic relationship between the oil recovery and the gravity number was obeyed by the physical model, the high-pressure corefloods and the field data.

  16. A SCHEDULING SCHEME WITH DYNAMIC FREQUENCY CLOCKING AND MULTIPLE VOLTAGES FOR LOW POWER DESIGNS

    Institute of Scientific and Technical Information of China (English)

    Wen Dongxin; Wang Ling; Yang Xiaozong

    2007-01-01

    In this letter, a scheduling scheme based on Dynamic Frequency Clocking (DFC) and multiple voltages is proposed for low power designs under the timing and the resource constraints.Unlike the conventional methods at high level synthesis where only voltages of nodes were considered,the scheme based on a gain function considers both voltage and frequency simultaneously to reduce energy consumption. Experiments with a number of DSP benchmarks show that the proposed scheme achieves an effective energy reduction.

  17. Sedations and analgesia in patients undergoing percutaneous transhepatic biliary drainage

    Energy Technology Data Exchange (ETDEWEB)

    Hatzidakis, A.A.; Charonitakis, E.; Athanasiou, A.; Tsetis, D.; Chlouverakis, G.; Papamastorakis, G.; Roussopoulou, G.; Gourtsoyiannis, N.C

    2003-02-01

    AIM: To present our experience using intravenous sedoanalgesia for percutaneous biliary drainage. MATERIALS AND METHODS: This study comprised 100 patients, all of whom were continuously monitored [electrocardiogram (ECG), blood pressure, pulse oxymetry] and received an initial dose of 2 mg midazolam followed by 0.02 mg fentanyl. Before every anticipated painful procedure, a maintenance dose of 0.01 mg fentanyl was administered. If the procedure continued and the patient became aware, another 1 mg midazolam was given. This was repeated if patients felt pain. A total dose of 0.08 mg fentanyl and 7 mg midazolam was never exceeded. Immediately after the procedure, the nurse was asked to evaluate patients' pain score. The patients were asked 3 h later to complete a visual 10-degree pain score scale. RESULTS: The average dose of fentanyl and midazolam was 0.042 mg (0.03-0.08 mg) and 4.28 mg (2-7 mg), respectively. Only one patient recorded the procedure as painful. The scores given by the attending nurse (1-7 points, mean 2.9) correlated well with those given by the patients (1-6 points, mean 2.72). No complications were noted. CONCLUSION: According to our experience, interventional radiologists practising biliary procedures can administer low doses of midazolam and minimize the doses of fentanyl, without loss of adequate sedation and analgesia. Hatzidakis, A. A. et al. (2003). Clinical Radiology58, 121-127.

  18. Unilobar versus bilobar biliary drainage: effect on quality of life and bilirubin level reduction

    Directory of Open Access Journals (Sweden)

    Shivanand Gamanagatti

    2016-01-01

    Conclusion: Percutaneous biliary drainage provides good palliation of malignant obstructive jaundice. Partial-liver drainage achieved results as good as those after complete liver drainage with significant improvements in QOL and reduction of the bilirubin level.

  19. Preliminary results from agricultural drainage water management CIG projects on Ohio

    Science.gov (United States)

    Field demonstrations were monitored to compare the crop yields, drainage discharge, and nutrient loadings to streams from managed and unmanaged subsurface drainage systems. Paired drainage systems within the same field, under similar soil, area, cropping, and management conditions, were identified. ...

  20. Investigating the impact of Lake Agassiz drainage routes on the 8.2 ka cold event with a climate model

    Directory of Open Access Journals (Sweden)

    Y.-X. Li

    2009-08-01

    Full Text Available The 8.2 ka event is the most prominent abrupt climate change in the Holocene and is often believed to result from catastrophic drainage of proglacial lakes Agassiz and Ojibway (LAO that routed through the Hudson Bay and the Labrador Sea into the North Atlantic Ocean, and perturbed Atlantic meridional overturning circulation (MOC. One key assumption of this triggering mechanism is that the LAO freshwater drainage was dispersed over the Labrador Sea. Recent data, however, show no evidence of lowered δ18O values, indicative of low salinity, from the open Labrador Sea around 8.2 ka. Instead, negative δ18O anomalies are found close to the east coast of North America, extending as far south as Cape Hatteras, North Carolina, suggesting that the freshwater drainage may have been confined to a long stretch of continental shelf before fully mixing with North Atlantic Ocean water. Here we conduct a sensitivity study that examines the effects of a southerly drainage route on the 8.2 ka event with the ECBilt-CLIO-VECODE model. Hosing experiments of four routing scenarios, where freshwater was introduced to the Labrador Sea in the northerly route and to three different locations along the southerly route, were performed to investigate the routing effects on model responses. The modeling results show that a southerly drainage route is possible but generally yields reduced climatic consequences in comparison to those of a northerly route. This finding implies that more freshwater would be required for a southerly route than for a northerly route to produce the same climate anomaly. The implicated large amount of LAO drainage for a southerly routing scenario is in line with a recent geophysical modelling study of gravitational effects on sea-level change associated with the 8.2 ka event, which suggests that the volume of drainage might be larger than previously estimated.

  1. Transport and retention of TiO2 and polystyrene nanoparticles during drainage from tall heterogeneous layered columns

    Science.gov (United States)

    Hoggan, James L.; Sabatini, David A.; Kibbey, Tohren C. G.

    2016-11-01

    Recent developments in nanotechnology have seen an increase in the use of manufactured nanomaterials. Although their unique physicochemical properties are desirable for many products and applications, concern continues to exist about their environmental fate and potential to cause risk to human and ecological health. The purpose of this work was to examine one aspect of nanomaterial environmental fate: transport and retention in the unsaturated zone during drainage. The work made use of tall segmented columns packed with layers of two different porous media, one medium sand and one fine sand. The use of tall columns allowed drainage experiments to be conducted where the water table remained within the height of the column, permitting control of final saturation profiles without the need for capillary barrier membranes which can potentially complicate analyses. Experiments were conducted with titanium dioxide (TiO2) and polystyrene nanomaterials. For the strongly negatively-charged polystyrene nanomaterials, little retention was observed under the conditions studied. For the TiO2 nanomaterials, results of the work suggest that while saturated fine sand layers may retain more nanomaterials than saturated coarse sand layers, significantly greater retention is possible in unsaturated media. Furthermore, unsaturated medium sand layers exhibited significantly greater retention than adjacent saturated fine sand layers when present at low saturations high above the water table. Retention by unsaturated media were found to correlate strongly with elevation. Free drainage experiments including both primary and secondary drainages in homogeneous columns showed evidence of redistribution during imbibition and secondary drainage, but still showed substantial unsaturated retention of TiO2 nanoparticles high in the column, despite re-saturation with- and drainage of nanoparticle-free water.

  2. Over-voltage protection system and method

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Song; Dong, Dong; Lai, Rixin

    2017-05-02

    An over-voltage protection system includes an electronic valve connected across two terminals of a circuit and an over-voltage detection circuit connected across one of the plurality of semiconductor devices for detecting an over-voltage across the circuit. The electronic valve includes a plurality of semiconductor devices connected in series. The over-voltage detection circuit includes a voltage divider circuit connected to a break-over diode in a way to provide a representative low voltage to the break-over diode and an optocoupler configured to receive a current from the break-over diode when the representative low voltage exceeds a threshold voltage of the break-over diode indicating an over-voltage condition. The representative low voltage provided to the break-over diode represents a voltage across the one semiconductor device. A plurality of self-powered gate drive circuits are connected to the plurality of semiconductor devices, wherein the plurality of self-powered gate drive circuits receive over-voltage triggering pulses from the optocoupler during the over-voltage condition and switch on the plurality of semiconductor devices to bypass the circuit.

  3. Advances in high voltage engineering

    CERN Document Server

    Haddad, A

    2005-01-01

    This book addresses the very latest research and development issues in high voltage technology and is intended as a reference source for researchers and students in the field, specifically covering developments throughout the past decade. This unique blend of expert authors and comprehensive subject coverage means that this book is ideally suited as a reference source for engineers and academics in the field for years to come.

  4. High Voltage Pulse Testing Survey.

    Science.gov (United States)

    1985-10-01

    Cryogenic 23 E. Liquids 26 F. Solids 28 1. Polyethylene 28 2. Cross-Linked Polyethylene ( XLPE ) 29 3. Polyimide and Polyvenylchloride (PVC) 31 VI Benefits 35 A...Strength of XLPE Cables 29 vii * 4" I PROGRAM OBJECTIVES The Pulse Test Survey summarizes government, industry, and technical reports on high voltage pulse...system of silicone oil on a XLPE (cross-linked polyethylene) spacer tends to lower the impulse breakdown by approximately 10 percent. The negative impulse

  5. TRANSISTOR HIGH VOLTAGE POWER SUPPLY

    Science.gov (United States)

    Driver, G.E.

    1958-07-15

    High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

  6. A DYNAMIC MIXED MODEL WITH NITROGEN LEACHING LOSSES FROM THE PONDED PADDY RICE FIELD UNDER SITUATION OF BURIED PIPE DRAINAGE

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In order to study the law of nitrogen leaching losses from the paddy field under the condition of drainage, based on the theories of potential energy and solute transport, a water-nitrogen dynamic mixed model by combining the flow net with dynamic method was established. In the computation of buried pipe drainage, the superposition principle was used to simplify the complex solving of the two-dimensional problem about water-nitrogen transportation in Soil-Plant-Air-Continuous (SPAC) system into several one-dimensional problems. The presented method is simple and practical. Some field experiments were carried out to demonstrate the validity of the model.

  7. Square-Wave Voltage Injection Algorithm for PMSM Position Sensorless Control With High Robustness to Voltage Errors

    DEFF Research Database (Denmark)

    Ni, Ronggang; Xu, Dianguo; Blaabjerg, Frede

    2017-01-01

    relationship with the magnetic field distortion. Position estimation errors caused by higher order harmonic inductances and voltage harmonics generated by the SVPWM are also discussed. Both simulations and experiments are carried out based on a commercial PMSM to verify the superiority of the proposed method...

  8. Low voltage electron beam accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

    2003-02-01

    Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

  9. Comparison of Methane Drainage Methods Used in Polish Coal Mines

    Science.gov (United States)

    Szlązak, Nikodem; Borowski, Marek; Obracaj, Dariusz; Swolkień, Justyna; Korzec, Marek

    2014-10-01

    Methane drainage is used in Polish coal mines in order to reduce mine methane emissions as well as to keep methane concentration in mine workings at safe levels. This article describes methods of methane drainage during mining used in Polish coal mines. The first method involves drilling boreholes from tailgate roadway to an unstressed zone in roof or floor layers of a mined seam. It is the main method used in Polish mining, where both the location of drilled boreholes as well as their parameters are dependent on mining and ventilation systems of longwalls. The second method is based on drilling overlying drainage galleries in seams situated under or over the mined seam. This article compares these methods with regard to their effectiveness under mining conditions in Polish mines. High effectiveness of methane drainage of longwalls with different ventilation and methane drainage systems has been proven. The highest effectiveness of methane drainage has been observed for the system with overlying drainage gallery and with the parallel tailgate roadways. In case of classic U ventilation system of longwall panel, boreholes drilled from the tailgate roadway behind the longwall front are lost.

  10. Systematic review comparing endoscopic, percutaneous and surgical pancreatic pseudocyst drainage

    Institute of Scientific and Technical Information of China (English)

    Anthony Yuen Bun Teoh; Vinay Dhir; Zhen-Dong Jin; Mitsuhiro Kida; Dong Wan Seo; Khek Yu Ho

    2016-01-01

    AIM: To perform a systematic review comparing the outcomes of endoscopic, percutaneous and surgical pancreatic pseudocyst drainage.METHODS: Comparative studies published between January 1980 and May 2014 were identified on Pub Med, Embase and the Cochrane controlled trials register and assessed for suitability of inclusion. The primary outcome was the treatment success rate. Secondary outcomes included were the recurrence rates, re-interventions, length of hospital stay, adverse events and mortalities.RESULTS: Ten comparative studies were identified and 3 were randomized controlled trials. Four studies reported on the outcomes of percutaneous and surgical drainage. Based on a large-scale national study, surgical drainage appeared to reduce mortality and adverse events rate as compared to the percutaneous approach. Three studies reported on the outcomes of endoscopic ultrasound(EUS) and surgical drainage. Clinical success and adverse events rates appeared to be comparable but the EUS approach reduced hospital stay, cost and improved quality of life. Three other studies comparedEUS and esophagogastroduodenoscopy-guided drainage. Both approaches were feasible for pseudocyst drainage but the success rate of the EUS approach was better for non-bulging cyst and the approach conferred additional safety benefits.CONCLUSION: In patients with unfavorable anatomy, surgical cystojejunostomy or percutaneous drainage could be considered. Large randomized studies with current definitions of pseudocysts and longer-term follow-up are needed to assess the efficacy of the various modalities.

  11. Technology of gas drainage and utilization in Huaibei mining area

    Institute of Scientific and Technical Information of China (English)

    LI Wei; XU Rui

    2009-01-01

    With the characteristics of coal seam geology and gas occurrence, a "ground-underground" integrated gas drainage method was formed, which can relieve gas pressure and increase permeability by mining the protection seams in conditional regions. After coal seam gas drainage, high gas outburst seam was converted to low gas safety seam. In the coal face mining process, safety and high efficient coal mining were realized by the measure of gas-suction over mining. In addition to the drainage gas for civil gas and gas power generation, the Huaibei Mining Group has actively carried out research on the utilization technology of methane drainage by ventilation. On the one hand, it can save precious energy; on the other hand, it can protect the environment for people's survival. In 2007, the amount of coal mine gas drainage was 120 hm3; the rate of coal mine gas drainage was 44%. Compared with the year 2002, the amount of coal mine gas drainage increased by two times. Meanwhile, the utilization rate of gas increased rapidly.

  12. The cold air drainage model KLAM_21

    Science.gov (United States)

    Kossmann, M.

    2010-09-01

    A brief description of the physics and numerical techniques of the cold air drainage model KLAM_21 is presented. The model has been developed by the Deutscher Wetterdienst (Sievers, 2005) for simulations of nocturnal airflow in hilly and mountainous terrain under dry fair weather conditions. The model has been widely used as an environmental consultancy tool. Typical model applications include frost protection (cold air ponding) and air quality (nocturnal ventilation). The single-layer model calculates the depth and the mean wind of a surface based stable layer that evolves from a neutrally stratified atmosphere during nighttime. The prediction of the velocity and direction of the cold air drainage is based on vertically averaged momentum tendency equations. Temporal changes in the total heat deficit in the cold air layer are calculated from a prescribed local heat loss rate (describing turbulent and radiative cooling) and advection (donor-cell algorithm). The depth of the cold air layer (depth of the surface based temperature inversion) is calculated diagnostically from the total heat loss deficit. The model is initialised with neutral stratification at sunset (onset time of nocturnal cooling). Optionally, effects of an ambient (regional) wind and/or the dispersion of a passive tracer can be simulated. Integration over time is carried out on a regular Arakawa C grid using dynamically calculated time steps. Spatial gradients are discretised using centred differential quotients. The standard size of the computational domains can reach up to 1500 x 1500 grid cells. Grid resolutions usually range between 10 m and 500 m. High resolution simulation can be limited to a nested inner grid domain, while the courser outer domain is covering the entire airshed of interest. A friendly user interface allows easy setup, control, and evaluation of model simulations. Some selected examples of KLAM_21 applications are shown to illustrate the features and capabilities of the model

  13. Temperature Stabilized Characterization of High Voltage Power Supplies

    CERN Document Server

    Krarup, Ole

    2017-01-01

    High precision measurements of the masses of nuclear ions in the ISOLTRAP experiment relies on an MR-ToF. A major source of noise and drift is the instability of the high voltage power supplies employed. Electrical noise and temperature changes can broaden peaks in time-of-flight spectra and shift the position of peaks between runs. In this report we investigate how the noise and drift of high-voltage power supplies can be characterized. Results indicate that analog power supplies generally have better relative stability than digitally controlled ones, and that the high temperature coefficients of all power supplies merit efforts to stabilize them.

  14. Environmental controls on drainage behavior of an ephemeral stream

    Science.gov (United States)

    Blasch, K.W.; Ferre, T. P. A.; Vrugt, J.A.

    2010-01-01

    Streambed drainage was measured at the cessation of 26 ephemeral streamflow events in Rillito Creek, Tucson, Arizona from August 2000 to June 2002 using buried time domain reflectometry (TDR) probes. An unusual drainage response was identified, which was characterized by sharp drainage from saturation to near field capacity at each depth with an increased delay between depths. We simulated the drainage response using a variably saturated numerical flow model representing a two-layer system with a high permeability layer overlying a lower permeability layer. Both the observed data and the numerical simulation show a strong correlation between the drainage velocity and the temperature of the stream water. A linear combination of temperature and the no-flow period preceding flow explained about 90% of the measured variations in drainage velocity. Evaluation of this correlative relationship with the one-dimensional numerical flow model showed that the observed temperature fluctuations could not reproduce the magnitude of variation in the observed drainage velocity. Instead, the model results indicated that flow duration exerts the most control on drainage velocity, with the drainage velocity decreasing nonlinearly with increasing flow duration. These findings suggest flow duration is a primary control of water availability for plant uptake in near surface sediments of an ephemeral stream, an important finding for estimating the ecological risk of natural or engineered changes to streamflow patterns. Correlative analyses of soil moisture data, although easy and widely used, can result in erroneous conclusions of hydrologic cause—effect relationships, and demonstrating the need for joint physically-based numerical modeling and data synthesis for hypothesis testing to support quantitative risk analysis.

  15. Piezo Voltage Controlled Planar Hall Effect Devices

    OpenAIRE

    Bao Zhang; Kang-Kang Meng; Mei-Yin Yang; Edmonds, K. W.; Hao Zhang; Kai-Ming Cai; Yu Sheng; Nan Zhang; Yang Ji; Jian-Hua Zhao; Hou-Zhi Zheng; Kai-You Wang

    2015-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the pie...

  16. Separation of drainage runoff during rainfall-runoff episodes using the stable isotope method and drainage water temperature

    Science.gov (United States)

    Zajíček, Antonín; Kvítek, Tomáš; Pomije, Tomáš

    2014-05-01

    Stabile isotopes of 2H 18O and drainage water temperature were used as natural tracers for separation rainfall-runoff event hydrograph on several tile drained catchments located in Bohemian-Moravian Highland, Czech Republic. Small agricultural catchments with drainage systems built in slopes are typical for foothill areas in the Czech and Moravian highland. Often without permanent surface runoff, the drainage systems represent an important portion of runoff and nitrogen leaching out of the catchment. The knowledge of the drainage runoff formation and the origin of its components are prerequisites for formulation of measures leading to improvement of the drainage water quality and reduction of nutrient leaching from the drained catchments. The results have proved presence of event water in the drainage runoff during rainfall-runoff events. The proportion of event water observed in the drainage runoff varied between 15 - 60 % in the summer events and 0 - 50 % in winter events, while the sudden water temperature change was between 0,1 - 4,2 °C (2 - 35 %). The comparison of isotope separation of the drainage runoff and monitoring the drainage water temperature have demonstrated that in all cases of event water detected in the runoff, a rapid change in the drainage water temperature was observed as well. The portion of event water in the runoff grows with the growing change in water temperature. Using component mixing model, it was demonstrated that water temperature can be successfully used at least as a qualitative and with some degree of inaccuracy as a quantitative tracer as well. The drawback of the non-conservative character of this tracer is compensated by both its economic and technical accessibility. The separation results also resemble results of separations at small streams. Together with a similarly high speed of the discharge reaction to beginning of precipitation, it is obvious that the mechanism of surface runoff formation and drainage runoff formation

  17. Simultaneous pancreas-kidney transplantation with enteric drainage of exocrine secretions

    Institute of Scientific and Technical Information of China (English)

    明长生; 曾凡军; 陈知水; 张伟杰; 林正斌; 刘斌; 蒋继贫; 魏来; 陈实; 陈忠华

    2003-01-01

    Objectives To simplify the enteric drainage (ED) procedure and to decrease surgical and metabolic complications in simultaneous pancreas-kidney transplantation (SPK) patients.Results This procedure was successfully applied in all 9 patients without complication referable to the technique. All patients had achieved euglycemia and excellent renal function, and stopped being dependent on an external insulin source. Fasting serum glucose fell from 9.5 preoperatively to 4.8 mmol/L and remained stable thereafter. At the time this paper was written, the grafts from eight patients were functioning well. Conclusions Our primary experience suggests that SPK with ED without Roux-en-Y anastomosis represents a more physiologic milieu, and a viable alternation to replace the bladder (BD) as the primary route of drainage for exocrine secretions of the pancreas. It is a feasible and safer procedure.

  18. Oil drainage by CO2 gas diffusion, dissolution and foaming in heavy oil

    Energy Technology Data Exchange (ETDEWEB)

    Kono, H; Sasaki, K.; Sugai, Y. [Department of Earth Resources Engineering, Kyushu University (Japan); Takahashi, T.; Ito, D.; Okabe, T. [Research Center, JAPEX (Japan)

    2011-07-01

    In the heavy oil industry, the injection of carbon dioxide into reservoirs is used as a method to enhance oil recovery and store CO2. During this process, dissolution of gas takes place and contributes to cold production through a reduction in oil viscosity and capillarity pressure and swelling of the oil. The aim of this study was to investigate oil drainage from the sandstone cores. Experiments were conducted in a high pressure cell with pressures up to 10MPa, to measure the swelling factors of heavy and light oils for CO2 gas dissolution and thus evaluate the swelling coefficient and diffusion coefficient of the oil. Results allowed the development of an equation to determine gas solubility in the heavy oil based on measurements of apparent density. This study showed that gas dissolution does not affect oil mobility but that foamy oil contributes to oil drainage.

  19. Development of Fiber Optically Driven Instrument for High-voltage Line Current

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The measurement theorem of fiber optically driven instrument for high-voltage line current is presented. The PLL voltage-frequency-narrow pulse principle and its micro-consumption mechanism are proposed, followed by analysis on the two main factors affecting PLL measurement precision. A software design scheme using 80C196KB micro-controller is introduced. The experiment result is satisfactory.

  20. 49 CFR 234.221 - Lamp voltage.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Lamp voltage. 234.221 Section 234.221 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.221 Lamp voltage. The voltage at each lamp shall...

  1. Bootstrapped Low-Voltage Analog Switches

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1999-01-01

    Novel low-voltage constant-impedance analog switch circuits are proposed. The switch element is a single MOSFET, and constant-impedance operation is obtained using simple circuits to adjust the gate and bulk voltages relative to the switched signal. Low-voltage (1-volt) operation is made feasible...

  2. Foam drainage wave coalescing and its energy evolution

    Institute of Scientific and Technical Information of China (English)

    SUN QiCheng; HUANG Jin; WANG GuangQian

    2008-01-01

    Liquid foam is a dense packing of gas bubbles in a small amount of surfactant solution. Liquid drains out of foams until equilibrium is reached due to the compromise between gravity and capillarity, which greatly affects the stability of foam. Based on a series of work on foam structure and drainage we conducted previously, this paper reports the results on coalescence of an original forced drainage wave at a low flow rate with subsequent drainage waves with higher flow rates. The evolutions of vis-cous energy and surface energy during the process of coalescence are theoretically analyzed.

  3. Application of digital elevation model in delineating drainage networks

    Institute of Scientific and Technical Information of China (English)

    SUN Yan-ling; XIE De-ti; LIU Hong-bin; WEI Chao-fu

    2005-01-01

    A practical method to extract drainage network from DEM (digital elevation model) is introduced. DEM pretreatment includes depression and flat areas treatment. The flow direction of each grid cell in DEM is calculated according to the 8-direction pour point model, and then the flow accumulation grid from the flow direction grid. With the flow accumulation grid, streams are defined according to the given threshold value of flow accumulation. Taking Gufo River watershed as an example, the extraction of drainage network was done from DEM. The results are basically consistent with the digitized drainage network from the relief maps.

  4. Drainage and tillage practices in the winter fallow season mitigate CH4 and N2O emissions from a double-rice field in China

    Science.gov (United States)

    Zhang, Guangbin; Yu, Haiyang; Fan, Xianfang; Yang, Yuting; Ma, Jing; Xu, Hua

    2016-09-01

    Traditional land management (no tillage, no drainage, NTND) during the winter fallow season results in substantial CH4 and N2O emissions from double-rice fields in China. A field experiment was conducted to investigate the effects of drainage and tillage during the winter fallow season on CH4 and N2O emissions and to develop mitigation options. The experiment had four treatments: NTND, NTD (drainage but no tillage), TND (tillage but no drainage), and TD (both drainage and tillage). The study was conducted from 2010 to 2014 in a Chinese double-rice field. During winter, total precipitation and mean daily temperature significantly affected CH4 emission. Compared to NTND, drainage and tillage decreased annual CH4 emissions in early- and late-rice seasons by 54 and 33 kg CH4 ha-1 yr-1, respectively. Drainage and tillage increased N2O emissions in the winter fallow season but reduced it in early- and late-rice seasons, resulting in no annual change in N2O emission. Global warming potentials of CH4 and N2O emissions were decreased by 1.49 and 0.92 t CO2 eq. ha-1 yr-1, respectively, and were reduced more by combining drainage with tillage, providing a mitigation potential of 1.96 t CO2 eq. ha-1 yr-1. A low total C content and high C / N ratio in rice residues showed that tillage in the winter fallow season reduced CH4 and N2O emissions in both early- and late-rice seasons. Drainage and tillage significantly decreased the abundance of methanogens in paddy soil, and this may explain the decrease of CH4 emissions. Greenhouse gas intensity was significantly decreased by drainage and tillage separately, and the reduction was greater by combining drainage with tillage, resulting in a reduction of 0.17 t CO2 eq. t-1. The results indicate that drainage combined with tillage during the winter fallow season is an effective strategy for mitigating greenhouse gas releases from double-rice fields.

  5. Grid-Voltage-Feedforward Active Damping for Grid-Connected Inverter with LCL Filter

    DEFF Research Database (Denmark)

    Lu, Minghui; Wang, Xiongfei; Blaabjerg, Frede;

    2016-01-01

    For the grid-connected voltage source inverters, the feedforward scheme of grid voltage is commonly adopted to mitigate the current distortion caused by grid background voltages harmonics. This paper investigates the grid-voltage-feedforward active damping for grid connected inverter with LCL fil...... for Phase Locked Loop (PLL). Simulation and experiment results are provided for verifying the theoretical analyses....... filter. It reveals that proportional feedforward control can not only fulfill the mitigation of grid disturbance, but also offer damping effects on the LCL filter resonance. Digital delays are intrinsic to digital controlled inverters; with these delays, the feedforward control can be equivalent...

  6. Long hole waterjet drilling for gas drainage

    Energy Technology Data Exchange (ETDEWEB)

    Matt Stockwell; M. Gledhill; S. Hildebrand; S. Adam; Tim Meyer [CMTE (Australia)

    2003-04-01

    In-seam drilling for gas drainage is now an essential part of operations at many Australian underground coalmines. The objective of this project is to develop and trial a new drilling method for the accurate and efficient installation of long inseam boreholes (>1000 metres). This involves the integration of pure water-jet drilling technology (i.e. not water-jet assisted rotary drilling) developed by CMTE with conventional directional drilling technology. The system was similar to conventional directional drilling methods, but instead of relying on a down-hole-motor (DHM) rotating a mechanical drill bit for cutting, high pressure water-jets were used. The testing of the system did not achieve the full objectives set down in the project plan. A borehole greater than 1000 metres was not achieved. The first trial site had coal that was weathered, oxidized and dry. These conditions significantly affected the ability of the drilling tool to stay 'in-seam'. Due to the poor conditions at the first trial, many experimental objectives were forwarded to the second field trial. In the second trial drilling difficulties were experienced, this was due to the interaction between the confinement of the borehole and the dimensions of the down hole drilling assembly. This ultimately reduced the productivity of the system and the distance that could be drilled within the specified trial periods. Testing in the first field trial did not show any indication that the system would have this difficulty.

  7. DROUGHT ANALYSIS IN OZANA DRAINAGE BASIN

    Directory of Open Access Journals (Sweden)

    Marina IOSUB

    2016-03-01

    Full Text Available Ozana drainage basin is located at the contact between large landscape units (the Carpathian mountains, the Subcarpathian area, and the plateau region. This placement determines the existence of a complex climate in the region. Despite being small in size, and its extension on an W-E direction, differences can be observed, especially of the way extreme phenomena take place. In the case of droughts, it had different intensities in the mountains, compared to the plateau region. In order to emphasize the different distribution on the territory, several climatic indexes have been calculated, regarding dryness (De Martonne Index, Hellman criterion. The analysis of these indexes at the same monitoring stations (Pluton, Leghin and Dumbrava emphasizes the growth of the drought periods in the plateau region and the fact that they shorten in the mountain area. In the mountainous area, where the land is very well forested, the values of the De Martonne index can reach 45.4, and in the plateau regions, where the forest associations are sparse, the values dropped to 30.6. According to the Hellman criterion, several differences can be emphasized, at basin level. In the mountainous region, there is only one month that, at a multi-annual level, has stood up among the rest, as being excessively droughty, while in the median /central region of the basin, three months have been identified, that have such potential, as well as five months, at Dumbrava.

  8. Distributed Low Voltage Ride-Through Operation of Power Converters in Grid-Connected Microgrids under Voltage Sags

    DEFF Research Database (Denmark)

    Zhao, Xin; Meng, Lexuan; Dragicevic, Tomislav;

    2015-01-01

    the voltage in all phases at AC common bus. However, since the line admittances from each converter to point of common coupling (PCC) are not identical, the injected reactive power may not be equally shared. In order to achieve low voltage ride through (LVRT) capability along with a good power sharing...... accuracy, a hierarchical control strategy is proposed in this paper. Droop control and virtual impedance is applied in primary control loop while secondary control loop is based on dynamic consensus algorithm (DCA). Experiments are conducted to verify the effectiveness of the proposed control strategy....

  9. Low voltage EELS—How low?

    Energy Technology Data Exchange (ETDEWEB)

    Stöger-Pollach, M., E-mail: stoeger@ustem.tuwien.ac.at

    2014-10-15

    Using low beam energies in a (scanning) transmission electron microscope (S/TEM) has numerous advantages over higher beam energies. We discuss the performance of commonly available electron microscopes when being operated at reduced beam energies. Further on, we discuss the merits of low beam energies concerning the determination of the optical properties of Si as well as of buried quantum structures. For this purpose we have aligned a conventional S/TEM and the attached energy loss spectrometer for 13 keV and 60 keV, respectively. Finally we identify the key parameters for setting up a low voltage electron energy loss spectrometry (EELS) experiment. - Highlights: • EELS at unconventional low beam energies in a TEM. • Optimization of scattering geometry for improving spatial resolution in VEELS. • Determination of the optical properties of Si free of relativistic artefacts.

  10. Plasma response to transient high voltage pulses

    Indian Academy of Sciences (India)

    S Kar; S Mukherjee

    2013-07-01

    This review reports on plasma response to transient high voltage pulses in a low pressure unmagnetized plasma. Mainly, the experiments are reviewed, when a disc electrode (metallic and dielectric) is biased pulsed negative or positive. The main aim is to review the electron loss in plasmas and particle balance during the negative pulse electrode biasing, when the applied pulse width is less than the ion plasma period. Though the applied pulse width is less than the ion plasma period, ion rarefaction waves are excited. The solitary electron holes are reviewed for positive pulsed bias to the electrode. Also the excitation of waves (solitary electron and ion holes) is reviewed for a metallic electrode covered by a dielectric material. The wave excitation during and after the pulse withdrawal, excitation and propagation characteristics of various electrostatic plasma waves are reviewed here.

  11. RICH High Voltages & PDF Analysis @ LHCb

    CERN Multimedia

    Fanchini, E

    2009-01-01

    In the LHCb experiment an important issue is the identification of the hadrons of the final states of the B mesons decays. Two RICH subdetectors are devoted to this task, and the Hybrid Photon Detectors (HPDs) are the photodetectors used to detect Cherenkov light. In this poster there is a description of how the very high voltage (-18 KV) supply stability used to power the HPDs is monitored. It is also presented the basics of a study which can be done with the first collision data: the analysis of the dimuons from the Drell-Yan process. This process is well known and the acceptance of the LHCb detector in terms of pseudorapidity will be very useful to improve the knowledge of the proton structure functions or, alternatively, try to estimate the luminosity from it.

  12. Correction factor based double model fuzzy logic control strategy of arc voltage in pulsed MIG welding

    Institute of Scientific and Technical Information of China (English)

    Wu Kaiyuan; Huang Shisheng; Meng Yongmin

    2005-01-01

    According to the feature of arc voltage control in welding steel using pulsed MIG welding, a correction factor based double model fuzzy logic controller (FLC) was developed to realize the arc voltage control by means of arc voltage feedback.When the error of peak arc voltage was great, a coarse adjusting fuzzy logic control rules with correction factor was designed,in the controller, the peak arc voltage was controlled by the wire feeding speed by means of arc voltage feedback. When the error of peak arc voltage was small, a fine adjusting fuzzy logic control rules with correction factor was designed, in this controller, the peak arc voltage was controlled by the background time by means of arc voltage feedback. The FLC was realized in a Look-Up Table ( LUT) method. Experiments had been carried out aiming at implementing the control strategy to control the arc length change in welding process. Experimental results show that the controller proposed enables the consistency of arc length and the stabolity of arc voltage and welding process to be achieved in pulsed MIG welding process.

  13. Estimation of the Frequency of Instantaneous Voltage Drops Dependent on Arrangement of Line Surge Arresters

    Science.gov (United States)

    Kawamura, Hironao; Kozuka, Masahiro; Itamoto, Naoki; Shinjo, Kazuo; Ishii, Masaru

    Lightning faults on transmission lines often cause instantaneous voltage drops in power systems. Influences of instantaneous voltage drops become increasingly serious in high technology industries etc. As countermeasures of instantaneous voltage drops, uninterruptible power supplies (UPS) are employed. On the other hand, line surge arresters are installed on transmission lines increasingly as one of the effective countermeasures of double-circuit faults caused by lightning strokes. Additionally, the arresters are effective as one of the reduction methods for the frequency of instantaneous voltage drops. In this paper, the frequency of instantaneous voltage drops reduced by installation of line surge arresters on transmission lines is estimated by employing EMTP analysis. Also, the accuracy of the method in estimating the frequency of instantaneous voltage drops in power systems is evaluated through comparison with experience.

  14. Bibliography for acid-rock drainage and selected acid-mine drainage issues related to acid-rock drainage from transportation activities

    Science.gov (United States)

    Bradley, Michael W.; Worland, Scott C.

    2015-01-01

    Acid-rock drainage occurs through the interaction of rainfall on pyrite-bearing formations. When pyrite (FeS2) is exposed to oxygen and water in mine workings or roadcuts, the mineral decomposes and sulfur may react to form sulfuric acid, which often results in environmental problems and potential damage to the transportation infrastructure. The accelerated oxidation of pyrite and other sulfidic minerals generates low pH water with potentially high concentrations of trace metals. Much attention has been given to contamination arising from acid mine drainage, but studies related to acid-rock drainage from road construction are relatively limited. The U.S. Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to evaluate the occurrence and processes controlling acid-rock drainage and contaminant transport from roadcuts in Tennessee. The basic components of acid-rock drainage resulting from transportation activities are described and a bibliography, organized by relevant categories (remediation, geochemical, microbial, biological impact, and secondary mineralization) is presented.

  15. Erosion characteristic of slope sandstone soaking in acid mine drainage

    Institute of Scientific and Technical Information of China (English)

    JIANG Li-chun; CHEN Jia-sheng; WU Ai-xiang

    2007-01-01

    Acid mine drainage(AMD) is one of the main reasons of slope instability in chemical mines with high sulfide. The pH values of the solution inside the mining pit decrease with the increasing of distance from ore body and vary from 1.2 to 4.6,according to the results of the water environmental investigation and the composition test of the slope sandstone in Xinqiao Pyrite Mine. Comparative experiments between original sandstone and AMD eroded sandstone samples show that after AMD erosion the uniaxial compressive strength and elastic modulus decrease by 30%-50% and 25%-45%, respectively, the cohesion and internal friction angle decrease obviously, and the Poisson ratio fluctuates between 0.20-0.29. The greater joints development, the higher residual stress after peak value, and the longer time to damage. Besides above, the reaction mechanism analysis of AMD eroded sandstone shows that the fillings in joints and fissures of sandstone are frequently decomposed and polyreacted, resulting in changes of interior molecule structure and framework composition, and decreases of cohesion and angle of internal friction between rock structure interfaces.

  16. Voltage Management in Unbalanced Low Voltage Networks Using a Decoupled Phase-Tap-Changer Transformer

    DEFF Research Database (Denmark)

    Coppo, Massimiliano; Turri, Roberto; Marinelli, Mattia

    2014-01-01

    The paper studies a medium voltage-low voltage transformer with a decoupled on load tap changer capability on each phase. The overall objective is the evaluation of the potential benefits on a low voltage network of such possibility. A realistic Danish low voltage network is used for the analysis...

  17. Estimating Voltage Asymmetry Making by One Phase Micro-generator in Low Voltage Network

    Directory of Open Access Journals (Sweden)

    Marian Sobierajski

    2014-12-01

    Full Text Available Connection of one phase micro-generator to the low voltage network increases voltage asymmetry. The voltage asymmetry is defined as the quotient of negative and positive voltage components. The mathematical background of exact and rough computation of the asymmetry quotient is presented in the paper. Considerations are illustrated by simple examples.

  18. 76 FR 70721 - Voltage Coordination on High Voltage Grids; Notice of Staff Workshop

    Science.gov (United States)

    2011-11-15

    ... Energy Regulatory Commission Voltage Coordination on High Voltage Grids; Notice of Staff Workshop Take notice that the Federal Energy Regulatory Commission will hold a Workshop on Voltage Coordination on High Voltage Grids on Thursday, December 1, 2011 from 9 a.m. to 4:30 p.m. This staff-led workshop will be...

  19. Improving transition voltage spectroscopy of molecular junctions

    DEFF Research Database (Denmark)

    Markussen, Troels; Chen, Jingzhe; Thygesen, Kristian Sommer

    2011-01-01

    Transition voltage spectroscopy (TVS) is a promising spectroscopic tool for molecular junctions. The principles in TVS is to find the minimum on a Fowler-Nordheim plot where ln(I/V2) is plotted against 1/V and relate the voltage at the minimum Vmin to the closest molecular level. Importantly, Vmin...... is approximately half the voltage required to see a peak in the dI/dV curve. Information about the molecular level position can thus be obtained at relatively low voltages. In this work we show that the molecular level position can be determined at even lower voltages, Vmin(α), by finding the minimum of ln...

  20. Piezo Voltage Controlled Planar Hall Effect Devices

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K. W.; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  1. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-22

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  2. Capacitor Voltages Measurement and Balancing in Flying Capacitor Multilevel Converters Utilizing a Single Voltage Sensor

    DEFF Research Database (Denmark)

    Farivar, Glen; Ghias, Amer M. Y. M.; Hredzak, Branislav

    2017-01-01

    This paper proposes a new method for measuring capacitor voltages in multilevel flying capacitor (FC) converters that requires only one voltage sensor per phase leg. Multiple dc voltage sensors traditionally used to measure the capacitor voltages are replaced with a single voltage sensor at the ac...... side of the phase leg. The proposed method is subsequently used to balance the capacitor voltages using only the measured ac voltage. The operation of the proposed measurement and balancing method is independent of the number of the converter levels. Experimental results presented for a five-level FC...

  3. Isotopic composition of Lake Agassiz-Ojibway water just prior to final drainage

    Science.gov (United States)

    Hillaire-Marcel, C.; Helie, J.; McKay, J.; Lalonde, A.

    2006-12-01

    Controversies persist with respect to the impact of the final drainage of Lake Agassiz-Ojibway on the thermohaline circulation of the North Atlantic, some 8.4 ka ago. The lack of response of planktic foraminifer isotope records, off Hudson Strait (i.e., at the outlet of the drainage channel) constitutes one of the most puzzling elements in this debate. However, data on the isotopic composition of drainage waters are needed to estimate the response of the 18-O-salinity relationship in NW Atlantic surface waters. In the literature, a large array of isotopic compositions have been suggested, notably for modeling experiment purposes. Scattered information about the isotopic composition of Lake Agassiz water does exist. It includes isotopic measurements of pore waters of lacustrine sediments [1], analyses of oxygen isotopes in cellulose from algal or plant remains [2], and stable isotope compositions of concretions from varves [3]. Whereas, relatively low oxygen isotope values (apx. -25 per mil vs. VSMOW) are inferred for Lake Agassiz waters during cold pulses of the deglaciation, most data suggest much higher values during the final stages of Lake Agassiz-Ojiway, just prior to its drainage. Calcareous concretions from Lake Ojibway varves (not necessarily contemporaneous to the lacustrine stage) yielded oxygen isotope compositions of about -10 per mil (vs. VPDB), suggesting values as high as -14 per mil (vs. VSMOW) for pore waters (assuming a 0-4 degrees C temperature range). Similar high values (as high as -8 per mil vs. VSMOW [1]) were also estimated from pore water analyses of contemporaneous Lake Agassiz sediments. Here, we used a core raised from Eastern Hudson Bay, off Great Whale River, to further document isotopic compositions of the lake waters prior to their drainage into the North Atlantic. The 7.40 m long core has an apx. 1.3 m-thick lacustrine layer at its base, including the drainage sub- layer. It is overlain by Tyrrell Sea clays. Scarce valves of Candona

  4. Fire history of southeastern Glacier National Park: Missouri River Drainage

    Science.gov (United States)

    Barrett, Stephen W.

    1993-01-01

    In 1982, Glacier National Park (GNP) initiated long-term studies to document the fire history of all forested lands in the 410,000 ha. park. To date, studies have been conducted for GNP west of the Continental Divide (Barrett et al. 1991), roughly half of the total park area. These and other fire history studies in the Northern Rockies (Arno 1976, Sneck 1977, Arno 1980, Romme 1982, Romme and Despain 1989, Barrett and Arno 1991, Barrett 1993a, Barrett 1993b) have shown that fire history data can be an integral element of fire management planning, particularly wen natiral fire plans are being developed for parks and wilderness. The value of site specific fire history data is apparent when considering study results for lodgepole pin (Pinus contorta var. latifolia) forests. Lodgepole pine is a major subalpine type in the Northern Rockies and such stands experiences a wide range of presettlement fire patterns. On relatively warm-dry sites at lower elevations, such as in GNP's North Fork drainage (Barrett et al. 1991), short to moderately long interval (25-150 yr) fires occurred in a mixed severity pattern ranging from non-lethal underburns to total stand replacement (Arno 1976, Sneck 1977, Barrett and Arno 1991). Markedly different fire history occurred at high elevation lodgepole pine stands on highly unproductive sites, such as on Yellowstone National Park's (YNP) subalpine plateau. Romme (1982) found that, on some sites, stand replacing fires recurred after very long intervals (300-400 yr), and that non-lethal surface fires were rare. For somewhat more productive sites in the Absaroka Mountains in YNP, Barrett (1993a) estimated a 200 year mean replacement interval, in a pattern similar to that found in steep mountain terrain elsewhere, such as in the Middle Fork Flathead River drainage (Barrett et al. 1991, Sneck 1977). Aside from post-1900 written records (ayres 1900; fire atlas data on file, GNP Archives Div. and GNP Resources Mgt. Div.), little fire history

  5. 1986 moose census, lower Nowitna River drainage: Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A moose survey of the lower Nowitna drainage on the Nowitna National Wildlife Refuge was conducted from 17-21 November 1986. The 1986 population estimate for the...

  6. Adaptive Drainage Slots for Acoustic Noise Attenuation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG) demonstrated feasibility in the reduction of noise attributed to drainage slots in jet engine acoustic liners. This was...

  7. Drainage report for Delair Division of Great River NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Obstacles such as ground seepage, inefficient water control structures, and backwater in the Sny Ditch are all contributing to drainage problems at the Delair...

  8. Monitoring and remediation technologies of organochlorine pesticides in drainage water

    Directory of Open Access Journals (Sweden)

    Ismail Ahmed

    2015-03-01

    Full Text Available This study was carried out to monitor the presence of organochlorine in drainage water in Kafr-El-Sheikh Governorate, Egypt. Furthermore, to evaluate the efficiencies of different remediation techniques (advanced oxidation processes [AOPs] and bioremediation for removing the most frequently detected compound (lindane in drainage water. The results showed the presence of several organochlorine pesticides in all sampling sites. Lindane was detected with high frequency relative to other detected organochlorine in drainage water. Nano photo-Fenton like reagent was the most effective treatment for lindane removal in drainage water. Bioremediation of lindane by effective microorganisms (EMs removed 100% of the lindane initial concentration. There is no remaining toxicity in lindane contaminated-water after remediation on treated rats relative to control with respect to histopathological changes in liver and kidney. Advanced oxidation processes especially with nanomaterials and bioremediation using effective microorganisms can be regarded as safe and effective remediation technologies of lindane in water.

  9. Recycling Facilities - Mine Drainage Treatment/Land Recycling Project Locations

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Mine Drainage Treatment/Land Reclamation Locations are clean-up projects that are working to eliminate some form of abandoned mine. The following sub-facility types...

  10. Gravity Drainage of Activated Sludge on Reed Beds

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Dominiak, Dominik Marek; Keiding, Kristian;

    Activated sludge is a by-product from waste water treatment plants, and the water content in the sludge is high (> 90%). Among several methods to remove the water, sludge drying reed beds are often used to dewater the sludge by drainage. There is, however, no well-defined criterion for design...... has therefore been developed to measure relevant quality parameters: specific cake resistance, settling velocity and cake compressibility. It has been found that activated sludge form highly compressible cake even at the low compressive pressures obtained during drainage. Numerical simulation shows...... that the compressibility has a high influence on the drainage process especially during the start-up phases where the volumetric load on the sludge bed is critical. The load has to be low in order to ensure that the drainage properties of the bed are not destroyed. The data also shows that transport of activated sludge...

  11. Fall 1979 moose surveys, Sheenjek, Old Woman, Coleen drainages

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Summary of fall moose population statistics for the upper Sheenjek River drainage (including all tributaries upstream of Lobo Lake) and of Old Woman Creek. William...

  12. Vegetation damage and recovery after Chiginagak Volcano Crater drainage event

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — From August 20 — 23, 2006, I revisited Chiginigak volcano to document vegetation recovery after the crater drainage event that severely damaged vegetation in May of...

  13. Adaptive Drainage Slots for Acoustic Noise Attenuation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG), proposes to demonstrate feasibility in the reduction of noise attributed to drainage slots in jet engine acoustic liners....

  14. Shallow Melting and Underground Drainage in Utopia Planitia, Mars

    Science.gov (United States)

    Costard, F.; Sejourne, A.; Kargel, J.; Soare, R.

    2012-03-01

    Based on the identification of sinuous and elongated pits in Utopia Planitia, we suggest that shallow melting and underground drainage are possible. We test that hypothesis using a thermal model that comprises a thick insulating dusty layer.

  15. 13 Morphometric Analysis of Ogunpa and Ogbere Drainage Basins ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    Morphometric Analysis of Ogunpa and Ogbere Drainage Basins, Ibadan, Nigeria. *Ajibade ... complex rock in Southwestern Nigeria. .... This work was based on map analysis ..... Bs = VI/HE where Bs = Basin slope, VI = Vertical Interval and.

  16. Voltage-Sensitive Load Controllers for Voltage Regulation and Increased Load Factor in Distribution Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Garcia-Valle, Rodrigo; Østergaard, Jacob

    2014-01-01

    consumption which can be mapped to temperature setpoint offsets of thermostat controlled loads. In networks where a lower voltage level corresponds to high system load (and vice versa), this controller acts to regulate voltage and increase the load factor. Simulations are conducted on low- and medium-voltage......This paper presents a novel controller design for controlling appliances based on local measurements of voltage. The controller finds the normalized voltage deviation accounting for the sensitivity of voltage measurements to appliance state. The controller produces a signal indicating desired power...... distribution systems with residential loads including voltage-sensitive water heaters. In low-voltage systems, the results of the simulations show the controller to be effective at reducing the extremes of voltage and increasing the load factor while respecting end-use temperature constraints. In medium-voltage...

  17. Voltage-controlled photonic oscillator.

    Science.gov (United States)

    Savchenkov, A A; Ilchenko, V S; Liang, W; Eliyahu, D; Matsko, A B; Seidel, D; Maleki, L

    2010-05-15

    We report the development and demonstration of an X-band voltage-controlled photonic oscillator based on a whispering gallery mode resonator made of an electro-optic crystalline material. The oscillator has good spectral purity and wide, agile, linear tunability. We have modified the existing theoretical model of the opto-electronic oscillator to describe the performance of our tunable oscillator and have found a good agreement between the theoretical predictions and the measurement results. We show that the device is promising for higher-frequency applications where high-performance tunable oscillators with wide tunability do not exist.

  18. Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils

    Directory of Open Access Journals (Sweden)

    Antônio Ocimar Manzi

    2011-04-01

    Full Text Available Central Amazonian rainforest landscape supports a mosaic of tall terra firme rainforest and ecotone campinarana, riparian and campina forests, reflecting topography-induced variations in soil, nutrient and drainage conditions. Spatial and temporal variations in litter decomposition, soil and groundwater chemistry and soil CO2 respiration were studied in forests on sandy soils, whereas drought sensitivity of poorly-drained valley soils was investigated in an artificial drainage experiment. Slightly changes in litter decomposition or water chemistry were observed as a consequence of artificial drainage. Riparian plots did experience higher litter decomposition rates than campina forest. In response to a permanent lowering of the groundwater level from 0.1 m to 0.3 m depth in the drainage plot, topsoil carbon and nitrogen contents decreased substantially. Soil CO2 respiration decreased from 3.7±0.6 µmol m-2 s-1 before drainage to 2.5±0.2 and 0.8±0.1 µmol m-2 s-1 eight and 11 months after drainage, respectively. Soil respiration in the control plot remained constant at 3.7±0.6 µmol m-2 s-1. The above suggests that more frequent droughts may affect topsoil carbon and nitrogen content and soil respiration rates in the riparian ecosystem, and may induce a transition to less diverse campinarana or short-statured campina forest that covers areas with strongly-leached sandy soil.

  19. Mercury mine drainage and processes that control its environmental impact

    Science.gov (United States)

    Rytuba, J.J.

    2000-01-01

    Mine drainage from mercury mines in the California Coast Range mercury mineral belt is an environmental concern because of its acidity and high sulfate, mercury, and methylmercury concentrations. Two types of mercury deposits are present in the mineral belt, silica-carbonate and hot-spring type. Mine drainage is associated with both deposit types but more commonly with the silica-carbonate type because of the extensive underground workings present at these mines. Mercury ores consisting primarily of cinnabar were processed in rotary furnaces and retorts and elemental mercury recovered from condensing systems. During the roasting process mercury phases more soluble than cinnabar are formed and concentrated in the mine tailings, commonly termed calcines. Differences in mineralogy and trace metal geochemistry between the two deposit types are reflected in mine drainage composition. Silica-carbonate type deposits have higher iron sulfide content than hot- spring type deposits and mine drainage from these deposits may have extreme acidity and very high concentrations of iron and sulfate. Mercury and methylmercury concentrations in mine drainage are relatively low at the point of discharge from mine workings. The concentration of both mercury species increases significantly in mine drainage that flows through and reacts with calcines. The soluble mercury phases in the calcines are dissolved and sulfate is added such that methylation of mercury by sulfate reducing bacteria is enhanced in calcines that are saturated with mine drainage. Where mercury mine drainage enters and first mixes with stream water, the addition of high concentrations of mercury and sulfate generates a favorable environment for methylation of mercury. Mixing of oxygenated stream water with mine drainage causes oxidation of dissolved iron(II) and precipitation of iron oxyhydroxide that accumulates in the streambed. Both mercury and methylmercury are strongly adsorbed onto iron oxyhydroxide over the p

  20. Low Voltage Ride-Through Capability of a Single-Stage Single-Phase Photovoltaic System Connected to the Low-Voltage Grid

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede

    2013-01-01

    The progressively growing of single-phase photovoltaic (PV) systems makes the Distribution System Operators (DSO) to update or revise the existing grid codes in order to guarantee the availability, quality and reliability of the electrical system. It is expected that the future PV systems connected...... to the low-voltage grid will be more active with functionalities of low voltage ride-through (LVRT) and the grid support capability, which is not the case today. In this paper, the operation principle is demonstrated for a single-phase grid-connected PV system in low voltage ride through operation in order...... to map future challenges. The system is verified by simulations and experiments. Test results show that the proposed power control method is effective and the single-phase PV inverters connected to low-voltage networks are ready to provide grid support and ride-through voltage fault capability...

  1. Airway physiology, autogenic drainage, and active cycle of breathing.

    Science.gov (United States)

    Lapin, Craig D

    2002-07-01

    Airway clearance techniques are used to aid in mucus clearance in a variety of disease states. Autogenic drainage and active-cycle-of-breathing technique are 2 such modalities that rely heavily on basic airway physiology to enhance clearance. In this review I discuss the equal pressure point, huffing, and asynchronous and collateral ventilation, and review the literature and theory regarding autogenic drainage and active cycle of breathing. Selection of airway clearance techniques is discussed in the light of evidence-based medicine.

  2. Abdominal drainage following cholecystectomy: high, low, or no suction?

    OpenAIRE

    McCormack, T T; Abel, P D; Collins, C. D.

    1983-01-01

    A prospective trial to assess the effect of suction in an abdominal drain following cholecystectomy was carried out. Three types of closed drainage system were compared: a simple tube drain, a low negative pressure drain, and a high negative pressure drain: 120 consecutive patients undergoing cholecystectomy were randomly allocated to one of the three drainage groups. There was no significant difference in postoperative pyrexia, wound infection, chest infection, or hospital stay. This study f...

  3. Voltage Management in Unbalanced Low Voltage Networks Using a Decoupled Phase-Tap-Changer Transformer

    OpenAIRE

    Coppo, Massimiliano; Turri, Roberto; Marinelli, Mattia; Han, Xue

    2014-01-01

    The paper studies a medium voltage-low voltage transformer with a decoupled on load tap changer capability on each phase. The overall objective is the evaluation of the potential benefits on a low voltage network of such possibility. A realistic Danish low voltage network is used for the analysis. The load profiles are characterized by using single phase measurement data on voltages, currents and active powers with a 10 minutes resolution. Different scenarios are considered: no tap action, th...

  4. Voltage Dependence of Conformational Dynamics and Subconducting States of VDAC-1.

    Science.gov (United States)

    Briones, Rodolfo; Weichbrodt, Conrad; Paltrinieri, Licia; Mey, Ingo; Villinger, Saskia; Giller, Karin; Lange, Adam; Zweckstetter, Markus; Griesinger, Christian; Becker, Stefan; Steinem, Claudia; de Groot, Bert L

    2016-09-20

    The voltage-dependent anion channel 1 (VDAC-1) is an important protein of the outer mitochondrial membrane that transports energy metabolites and is involved in apoptosis. The available structures of VDAC proteins show a wide β-stranded barrel pore, with its N-terminal α-helix (N-α) bound to its interior. Electrophysiology experiments revealed that voltage, its polarity, and membrane composition modulate VDAC currents. Experiments with VDAC-1 mutants identified amino acids that regulate the gating process. However, the mechanisms for how these factors regulate VDAC-1, and which changes they trigger in the channel, are still unknown. In this study, molecular dynamics simulations and single-channel experiments of VDAC-1 show agreement for the current-voltage relationships of an "open" channel and they also show several subconducting transient states that are more cation selective in the simulations. We observed voltage-dependent asymmetric distortions of the VDAC-1 barrel and the displacement of particular charged amino acids. We constructed conformational models of the protein voltage response and the pore changes that consistently explain the protein conformations observed at opposite voltage polarities, either in phosphatidylethanolamine or phosphatidylcholine membranes. The submicrosecond VDAC-1 voltage response shows intrinsic structural changes that explain the role of key gating amino acids and support some of the current gating hypotheses. These voltage-dependent protein changes include asymmetric barrel distortion, its interaction with the membrane, and significant displacement of N-α amino acids.

  5. Percutaneous transhepatic biliary drainage: analysis of 175 cases

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Kyung Jin; Lee, Sang Kwon; Kim, Tae Hun; Kim, Yong Joo; Kang, Duk Sik [College of Medicine, Kyungpook National Univ., Daegu (Korea, Republic of)

    1990-10-15

    Percutaneous transhepatic biliary drainage is a safe, effective and palliative means of treatment in biliary obstruction, especially in cases with malignant obstruction which are inoperable. 175 cases of transhepatic biliary drainage were performed on 119 patients with biliary obstruction from January 1985 to June 1989 at Kyung-pook National University Hospital. The causes of obstructive jaundice were 110 malignant diseases and 9 benign diseases. The most common indication for drainage was palliative intervention of obstruction secondary to malignant tumor in 89 cases. 86 cases of external drainage were performed including 3 cases of left duct approach, 29 cases of external-internal drainage and 60 cases of endoprosthesis. In external and external-internal drainages, immediate major complications (11.9%) occurred, including not restricted to, but sepsis, bile peritonitis and hemobilia. Delayed major complications (42.9%) were mainly catheter related. The delayed major complication of endoprosthesis resulted from obstruction of the internal stent. The mean time period to reobstruction of the internal stent was about 12 weeks. To improve management status, regular follow-up is required, as is education of both patients and their families as to when immediate clinical attention is mandated. Close communication amongst the varying medical specialities involved will be necessary to provide optional treatment for each patient.

  6. Percutaneous catheter drainage of intraabdominal abscesses and fluid

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tae; Kwon, Tae Hee; Yoo, Hyung Sik; Suh, Jung Ho [Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Young Ho [Cheil General Hospital, Seoul (Korea, Republic of)

    1986-10-15

    Percutaneous catheter drainage has been reported to be an effective method in the management of selected patients with abscess and fluid collection. Its high success rate and relatively low complications make the procedure an alternative to surgery in the individual cases. During past two years percutaneous catheter drainage in 25 patients with intraabdominal abscesses and fluid collection was performed at the Department of Radiology, Yonsei University College of medicine. Here the technique and author's results were summarized. 1. The total 25 patients who had percutaneous catheter drainage are 10 liver abscesses, 3 subphrenic, one subhepatic, 4 renal and perirenal, 2 pelvic, one psoas, one anterior pararenal fluid from acute pancreatitis, one pancreas pseudocyst and 2 malignant tumor necrosis. 2. The modified Seldinger technique used for all cases of abscess and fluid drainage under guidance of ultrasound scan. The used catheters were 10F. Pigtail and 14F. Malecot (Cook c/o) catheters. 3. The abscesses and fluid of 17 patients among 25 were cured by the percutaneous catheter drainage and 4 patients were clinically improved. The catheter drainage was failed in 2 patients and 3 complication were developed. 4. The success rate of this procedure was 91.3%, failure rate was 8.7% and complication rate was 12%.

  7. Effects of drainage salinity evolution on irrigation management

    Science.gov (United States)

    Kan, Iddo

    2003-12-01

    A soil physics theory of solute movement through a drained saturated zone underlying agricultural land is introduced into a long-term economic analysis of farm-level irrigation management; this is an alternative to the immediate, homogeneous blending assumption employed in previous studies as a base for calculating changes in drainage salinity over time. Using data from California, the effect of drainage salinity evolution is analyzed through a year-by-year profit optimization under the requirement of on-farm drainage disposal. Paths of optimal land allocation among crop production with fresh surface water, saline drainage reuse and evaporation ponds appear to depend on the relative profitability of the first two; that of reuse is affected by the trend of drainage salinity. Tile spacing and environmental regulations associated with evaporation ponds affect the timing of evaporation pond construction. The system converges into a solution involving both drainage-disposal activities; this solution includes an outlet for salts and is therefore sustainable. Following this strategy, the system is asymptotically approaching a steady state that possesses both hydrological and salt balances. Economic implications associated with land retirement programs in California are discussed.

  8. A cost comparison of traditional drainage and SUDS in Scotland.

    Science.gov (United States)

    Duffy, A; Jefferies, C; Waddell, G; Shanks, G; Blackwood, D; Watkins, A

    2008-01-01

    The Dunfermline Eastern Expansion (DEX) is a 350 ha mixed development which commenced in 1996. Downstream water quality and flooding issues necessitated a holistic approach to drainage planning and the site has become a European showcase for the application of Sustainable Urban Drainage Systems (SUDS). However, there is minimal data available regarding the real costs of operating and maintaining SUDS to ensure they continue to perform as per their design function. This remains one of the primary barriers to the uptake and adoption of SUDS. This paper reports on what is understood to be the only study in the UK where actual costs of constructing and maintaining SUDS have been compared to an equivalent traditional drainage solution. To compare SUDS costs with traditional drainage, capital and maintenance costs of underground storage chambers of analogous storage volumes were estimated. A whole life costing methodology was then applied to data gathered. The main objective was to produce a reliable and robust cost comparison between SUDS and traditional drainage. The cost analysis is supportive of SUDS and indicates that well designed and maintained SUDS are more cost effective to construct, and cost less to maintain than traditional drainage solutions which are unable to meet the environmental requirements of current legislation. (c) IWA Publishing 2008.

  9. Spatial and temporal distribution of drainage and solute leaching in heterogeneous urban vegetation environments

    Science.gov (United States)

    Nouri, H.; Beecham, S.; Hassanli, A. M.; Ingleton, G.

    2013-05-01

    Deep percolation enhancement from recycled wastewater irrigation may contribute to salt accumulation and water table elevation that can ultimately cause soil and ground water degradation. The spatial and temporal variation of drainage rate and solute leaching were investigated in an urban park containing heterogeneous landscape plants that were irrigated with recycled wastewater. Field monitoring was undertaken at Veale Gardens in the Adelaide Parklands, Australia. Based on the landscape variation in Veale Gardens, two landscape zones were defined: one being largely covered with turf grasses with few trees and shrubs (MG) with the second zone being mostly trees and shrubs with intermittent turf grasses (MT). Experiments were performed using two zero-tension lysimeters placed horizontally 100 cm below ground to monitor the spatio-temporal behaviour of drained water and nutrient loadings for four seasons. The outcomes showed a large spatial and temporal variation of drainage quantity and quality in the MT and MG zones. The low vegetation cover in the MG zone resulted in more drained water than in the high vegetation cover (MT zone). In both zones, more drainage water was collected in winter than in other seasons. This is in spite of the input water showing a maximum rate in summer. The seasonal salinities measured in the two lysimeters showed very similar trends with the lowest salinity rate in autumn with the levels increasing through winter and spring. Chemical analyses of the leachate solute indicated no detrimental impact from using recycled wastewater during the study period.

  10. Variability of drainage and solute leaching in heterogeneous urban vegetation environs

    Science.gov (United States)

    Nouri, H.; Beecham, S.; Hassanli, A. M.; Ingleton, G.

    2013-11-01

    Deep percolation enhancement from recycled wastewater irrigation may contribute to salt accumulation and water table elevation that can ultimately cause soil and ground water degradation. Variation of drainage rate and solute leaching were investigated in an urban park containing heterogeneous landscape plants that were irrigated with recycled wastewater. Field monitoring was undertaken at Veale Gardens in the Adelaide Parklands, Australia. Based on landscape variation in Veale Gardens, two landscape zones were defined: one being largely covered with turf grasses with few trees and shrubs (MG) with the second zone being mostly trees and shrubs with intermittent turf grasses (MT). Experiments were performed on two zero-tension lysimeters placed horizontally 100 cm below ground to monitor the variation of volume and quality indicators of drained water for four seasons. The outcomes showed a significant variation of drainage quantity and quality in the MT and MG zones. The low vegetation cover in the MG zone resulted in more drained water than in the high vegetation cover (MT zone). In both zones, more drainage water was collected in winter than in other seasons. This is in spite of the input water showing a maximum rate in summer. The seasonal salinities measured in the two lysimeters showed very similar trends with the lowest salinity rate in autumn with the levels increasing through winter and spring. Chemical analyses of leachate solute and salt loading indicated no impact from using recycled wastewater.

  11. Acid mine drainage treatment using by-products from quicklime manufacturing as neutralization chemicals.

    Science.gov (United States)

    Tolonen, Emma-Tuulia; Sarpola, Arja; Hu, Tao; Rämö, Jaakko; Lassi, Ulla

    2014-12-01

    The aim of this research was to investigate whether by-products from quicklime manufacturing could be used instead of commercial quicklime (CaO) or hydrated lime (Ca(OH)2), which are traditionally used as neutralization chemicals in acid mine drainage treatment. Four by-products were studied and the results were compared with quicklime and hydrated lime. The studied by-products were partly burnt lime stored outdoors, partly burnt lime stored in a silo, kiln dust and a mixture of partly burnt lime stored outdoors and dolomite. Present application options for these by-products are limited and they are largely considered waste. Chemical precipitation experiments were performed with the jar test. All the studied by-products removed over 99% of Al, As, Cd, Co, Cu, Fe, Mn, Ni, Zn and approximately 60% of sulphate from acid mine drainage. However, the neutralization capacity of the by-products and thus the amount of by-product needed as well as the amount of sludge produced varied. The results indicated that two out of the four studied by-products could be used as an alternative to quicklime or hydrated lime for acid mine drainage treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Drainage, rupture, and lifetime of deionized water films: effect of dissolved gases?

    Science.gov (United States)

    Nguyen, Phong T; Nguyen, Anh V

    2010-03-02

    Gas bubbles coalesce in deionized (DI) water because the water (foam) films between the bubbles are not stable. The so-called hydrophobic attraction has been suggested as the cause of the film instability and the bubble coalescence. In this work, microinterferometry experiments show that foam films of ultrapure DI water can last up to 10 s and the contact time between the two gas bubble surfaces at close proximity (approximately 1 microm separation distance) significantly influences the film drainage, rupture, and lifetime. Specifically, when the two bubbles were first brought into contact, the films instantly ruptured at 0.5 microm thickness. However, the film drainage rate and rupture thickness sharply decreased and the film lifetime steeply increased with increasing contact time up to 10 min, but then they leveled off. The constant thickness of film rupture was around 35 nm. Possible contamination was vigorously investigated and ruled out. It is argued that migration of gases inherently dissolved in water might cause the transient behavior of the water films at the short contact time. The film drainage rate and instability at the long contact time were analyzed employing Eriksson et al.'s phenomenological theory of long-range hydrophobic attraction (Eriksson, J. C.; Ljunggren, S.; Claesson, P. M., J. Chem. Soc., Faraday Trans. 2 1989, 85, 163-176) and the hypothesis of water molecular structure modified by dissolved gases, and the extended Stefan-Reynolds theory by incorporating the mobility of the air-DI-water interfaces.

  13. DRAINAGE AND RETENTION ENHANCEMENT OF A WHEAT STRAW PULP CONTAINING FURNISH USING MICROPARTICLE RETENTION AIDS

    Directory of Open Access Journals (Sweden)

    Tom Hultholm

    2011-02-01

    Full Text Available The usage of non-wood pulps in furnishes for the production of various paper grades is a real alternative for the substitution of wood pulp in papermaking. In terms of the papermaking process, the main limiting factor for non-wood pulp utilization is poor dewatering. This problem can be partially solved by means of retention aids, and the modern microparticle-based retention aids are very promising for this application. In this study the main aim was to characterize how the microparticle retention systems affect the retention, dewatering, and formation of a non-wood pulp furnish and how these effects and mechanisms differ when compared to normal wood pulp. The performance of several commercially available retention aids was studied by making dynamic sheet forming tests for reference and an organosolv wheat straw furnish. The emphasis in the experiments was on drainage enhancement. The maximum drainage gain obtained with the bentonite-CPAM retention aid system was about 5%. Despite the improved drainage, dewatering of the reference furnish was better than for the non-wood containing furnish.

  14. 21 CFR 878.4200 - Introduction/drainage catheter and accessories.

    Science.gov (United States)

    2010-04-01

    ... catheters (including dialysis), and other general surgical catheters. An introduction/drainage catheter... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Introduction/drainage catheter and accessories... Introduction/drainage catheter and accessories. (a) Identification. An introduction/drainage catheter is a...

  15. Low-Driving-Voltage Optical Modulation Utilizing FWM for High-Speed Transmission Systems

    Institute of Scientific and Technical Information of China (English)

    Akihiko; Matsuura; Toshiya; Matsuda; Tomoyoshi; Kataoka

    2003-01-01

    We propose an optical transmitter with reduced modulator driving voltage. This reduction is achieved through an on-off ratio improvement technique based on FWM. We confirmed the feasibility of the method in a 43-Gbit/s experiment.

  16. Surgical vs ultrasound-guided drainage of deep neck space abscesses: a randomized controlled trial: surgical vs ultrasound drainage

    OpenAIRE

    2013-01-01

    Introduction Deep neck space abscesses (DNAs) are relatively common otolaryngology-head and neck surgery emergencies and can result in significant morbidity with potential mortality. Traditionally, surgical incision and drainage (I&D) with antibiotics has been the mainstay of treatment. Some reports have suggested that ultrasound-guided drainage (USD) is a less invasive and effective alternative in select cases. Objectives To compare I&D vs USD of well-defined DNAs, using a randomized control...

  17. 49 CFR 236.551 - Power supply voltage; requirement.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Power supply voltage; requirement. 236.551 Section... supply voltage; requirement. The voltage of power supply shall be maintained within 10 percent of rated voltage....

  18. Use of endoscopic naso-pancreatic drainage in the treatment of severe acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Zhu-Fu Quan; Zhi-Ming Wang; Wei-Qin Li; Jie-Shou Li

    2003-01-01

    AIM: To review the experience on the use of endoscopic nasopancreatic drainage (ENPD) in the treatment of severe acute pancreatitis (SAP).METHODS: Since March 1998, under the regular management of SAP with non-operative method, ENPD has been randomly used in 14 patients. The average age of the patients was 41.3±15.9 (years), with 8 males and 6 females.The time from onset to admission was 32.9±22.8 (hours). 8cases were found to have gallbladder stone. The daily output of pancreatic fluid was measured. The body temperature,heart rate, WBC count, blood glucose, blood calcium, PaO2,blood and urine levels of amylase were detected on the fifth day and compared with their respective data on the first day.Therapeutic results and hospitalization times were recorded.RESULTS: The time of drainage was 7.3±4.0 days. The daily drainage outputs of the first five days were 236.4±176.6,287.1±164.7, 284.6±216.4, 435.0±357.8 and 377.8±223.8 ml,respectively. The decreases in body temperature, heart rate,WBC counts, blood and urine levels of amylase and the increase in PaO2 were significant on the fifth day when compared with those on the first day. Infection of pancreatic necrosis was found in one patient and controlled by antiinfectives. 6 out of 8 patients with gallbladder stone were operated during hospital stay. All patients were cured and diischarged and the average hospital stay was 28.1±11.6 days.CONCLUSION: ENPD is an effective method for the drainage of pancreatic fluid and might have an important role in the treatment of SAP. Further observation, comparison and summary by this method are worthy to be considered.

  19. Sensitivity of drainage efficiency of cranberry fields to edaphic conditions

    Science.gov (United States)

    Periard, Yann; José Gumiere, Silvio; Rousseau, Alain N.; Caron, Jean; Hallema, Dennis W.

    2014-05-01

    Water management on a cranberry farm requires intelligent irrigation and drainage strategies to sustain strong productivity and minimize environmental impact. For example, to avoid propagation of disease and meet evapotranspiration demand, it is imperative to maintain optimal moisture conditions in the root zone, which depends on an efficient drainage system. However, several drainage problems have been identified in cranberry fields. Most of these drainage problems are due to the presence of a restrictive layer in the soil profile (Gumiere et al., 2014). The objective of this work is to evaluate the effects of a restrictive layer on the drainage efficiency by the bias of a multi-local sensitivity analysis. We have tested the sensitivity of the drainage efficiency to different input parameters set of soil hydraulic properties, geometrical parameters and climatic conditions. Soil water flux dynamic for every input parameters set was simulated with finite element model Hydrus 1D (Simanek et al., 2008). Multi-local sensitivity was calculated with the Gâteaux directional derivatives with the procedure described by Cheviron et al. (2010). Results indicate that drainage efficiency is more sensitive to soil hydraulic properties than geometrical parameters and climatic conditions. Then, the geometrical parameters of the depth are more sensitive than the thickness. The drainage efficiency was very insensitive to the climatic conditions. Understanding the sensitivity of drainage efficiency according to soil hydraulic properties, geometrical and climatic conditions are essential for diagnosis drainage problems. However, it becomes important to identify the mechanisms involved in the genesis of anthropogenic soils cranberry to identify conditions that may lead to the formation of a restrictive layer. References: Cheviron, B., S.J. Gumiere, Y. Le Bissonnais, R. Moussa and D. Raclot. 2010. Sensitivity analysis of distributed erosion models: Framework. Water Resources Research

  20. Voltage Unbalance Compensation with Smart Three-phase Loads

    DEFF Research Database (Denmark)

    Douglass, Philip; Trintis, Ionut; Munk-Nielsen, Stig

    2016-01-01

    voltage, but it does not reduce the negative sequence voltage. The controller that uses phase-phase voltage as input eliminates negative sequence voltage, and reduces voltage deviations from the average to approximately half their initial value. Current unbalance is reduced when the voltage unbalance...... is caused by asymmetrical loads. These results suggest that the optimal algorithm to reduce system unbalance depends on which system parameter is most important: phase-neutral voltage unbalance, phase-phase voltage unbalance, or current unbalance....

  1. Study of the plasma interference with high voltage electrode array for space power application

    OpenAIRE

    Iwasa, Minoru; TANAKA, KOJI; Sasaki, Susumu; ODAWARA, OSAMU; 岩佐 稔; 田中 孝治; 佐々木 進; 小田原 修

    2005-01-01

    We are studying the problems associated with high voltage power systems in space. Especially we are interested in the potential distribution of the solar array that is resistant to the electrical discharge. We have carried out experiments on the interaction between the high voltage solar array and the ambient plasma. In the experiment, an array of electrodes distributed on the insulation panel was used to simulate the inter-connectors of the solar array. An electrode array without the insulat...

  2. Power conditioning using dynamic voltage restorers under different voltage sag types

    Directory of Open Access Journals (Sweden)

    Ahmed M. Saeed

    2016-01-01

    Full Text Available Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs. By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented. The performance of the device under different voltage sag types is described, where the voltage sag types are introduced using the different types of short-circuit faults included in the environment of the MatLab/Simulink package. The robustness of the proposed device is evaluated using the common voltage sag indices, while taking into account voltage and current unbalance percentages, where maintaining the total harmonic distortion percentage of the load voltage within a specified range is desired. Finally, several simulation results are shown in order to highlight that the DVR is capable of effective correction of the voltage sag while minimizing the grid voltage unbalance and distortion, regardless of the fault type.

  3. Power conditioning using dynamic voltage restorers under different voltage sag types.

    Science.gov (United States)

    Saeed, Ahmed M; Abdel Aleem, Shady H E; Ibrahim, Ahmed M; Balci, Murat E; El-Zahab, Essam E A

    2016-01-01

    Voltage sags can be symmetrical or unsymmetrical depending on the causes of the sag. At the present time, one of the most common procedures for mitigating voltage sags is by the use of dynamic voltage restorers (DVRs). By definition, a DVR is a controlled voltage source inserted between the network and a sensitive load through a booster transformer injecting voltage into the network in order to correct any disturbance affecting a sensitive load voltage. In this paper, modelling of DVR for voltage correction using MatLab software is presented. The performance of the device under different voltage sag types is described, where the voltage sag types are introduced using the different types of short-circuit faults included in the environment of the MatLab/Simulink package. The robustness of the proposed device is evaluated using the common voltage sag indices, while taking into account voltage and current unbalance percentages, where maintaining the total harmonic distortion percentage of the load voltage within a specified range is desired. Finally, several simulation results are shown in order to highlight that the DVR is capable of effective correction of the voltage sag while minimizing the grid voltage unbalance and distortion, regardless of the fault type.

  4. Drainage filters and constructed wetlands to mitigate site-specific nutrient losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Hoffmann, Carl Christian; Iversen, Bo Vangsø

    options targeting subsurface drainage are lacking. An end-of-pipe drainage filter solution offers the benefits of a targeted measure typically applied to point sources. This calls for a shift of paradigm towards the development of new, cost-efficient technologies to mitigate site-specific nutrient losses...... drainage. The project studies different approaches of implementing the filter technologies including drainage well or drainage pipe filters as well as surface-flow and sub-surface flow constructed wetlands....

  5. Nitrogen budget in the Changjiang River drainage area

    Institute of Scientific and Technical Information of China (English)

    JIANG Tao; YU Zhiming; SONG Xiuxian; CAO Xihua

    2012-01-01

    We established a budget model of nitrogen (N) inputs and outputs between watersheds and waterbodies to determine the sources of riverine N in the Changjiang (Yangtze) River drainage area.Nitrogen inputs in the budget included N from synthetic fertilizer,biological fixation by leguminous and other crops,wet/dry atmospheric deposition,excreta from humans and animals,and crop residues.The total N input was estimated to be 17.6 Tg,of which 20% or 3.5 Tg N was transported into waterbodies.Of the total N transported into waterbodies,the largest proportion was N from animal waste (26%),followed by N from atmospheric wet/dry deposition (25%),synthetic fertilizer N (17%),N in sewage wastes (17%),N in human waste from rural areas (6%) and industrial wastewater N (9%).We studied the spatial patterns of N inputs and outputs by dividing the Changjiang River drainage area into four sub-basins,from upstream to downstream:the Tongtian River drainage area (TTD,the headwater drainage area,138 000 km2,less disturbed by human activities); the Jinsha River drainage area (JSD,347 000 km2,less disturbed by human activities,approx.3 500 km upstream of the Changjiang estuary); the Pingshan-Yichang drainage area (PYD,520 500 km2,large-scale human disturbance,about 2 000 km upstream of the Changjiang estuary);and the Yichang-Datong drainage area (YDD,699 900 km2,large-scale human disturbance,approx.620 km upstream of the Changjiang estuary).The average N input into waterbodies was 2.3,7.3,24.1,and 28.2 kg N/ha in the TTD,JSD,PYD,and YDD sub-basins,respectively,suggesting an increase of N-components of more than 10 times from upstream to downstream areas.

  6. High voltage load resistor array

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, Monty Ray [Smithfield, VA

    2005-01-18

    A high voltage resistor comprising an array of a plurality of parallel electrically connected resistor elements each containing a resistive solution, attached at each end thereof to an end plate, and about the circumference of each of the end plates, a corona reduction ring. Each of the resistor elements comprises an insulating tube having an electrode inserted into each end thereof and held in position by one or more hose clamps about the outer periphery of the insulating tube. According to a preferred embodiment, the electrode is fabricated from stainless steel and has a mushroom shape at one end, that inserted into the tube, and a flat end for engagement with the end plates that provides connection of the resistor array and with a load.

  7. Geochemical characterisation of seepage and drainage water quality from two sulphide mine tailings impoundments: Acid mine drainage versus neutral mine drainage

    Science.gov (United States)

    Heikkinen, P.M.; Raisanen, M.L.; Johnson, R.H.

    2009-01-01

    Seepage water and drainage water geochemistry (pH, EC, O2, redox, alkalinity, dissolved cations and trace metals, major anions, total element concentrations) were studied at two active sulphide mine tailings impoundments in Finland (the Hitura Ni mine and Luikonlahti Cu mine/talc processing plant). The data were used to assess the factors influencing tailings seepage quality and to identify constraints for water treatment. Changes in seepage water quality after equilibration with atmospheric conditions were evaluated based on geochemical modelling. At Luikonlahti, annual and seasonal changes were also studied. Seepage quality was largely influenced by the tailings mineralogy, and the serpentine-rich, low sulphide Hitura tailings produced neutral mine drainage with high Ni. In contrast, drainage from the high sulphide, multi-metal tailings of Luikonlahti represented typical acid mine drainage with elevated contents of Zn, Ni, Cu, and Co. Other factors affecting the seepage quality included weathering of the tailings along the seepage flow path, process water input, local hydrological settings, and structural changes in the tailings impoundment. Geochemical modelling showed that pH increased and some heavy metals were adsorbed to Fe precipitates after net alkaline waters equilibrated with the atmosphere. In the net acidic waters, pH decreased and no adsorption occurred. A combination of aerobic and anaerobic treatments is proposed for Hitura seepages to decrease the sulphate and metal loading. For Luikonlahti, prolonged monitoring of the seepage quality is suggested instead of treatment, since the water quality is still adjusting to recent modifications to the tailings impoundment.

  8. Voltage-Controlled Floating Resistor Using DDCC

    Directory of Open Access Journals (Sweden)

    M. Kumngern

    2011-04-01

    Full Text Available This paper presents a new simple configuration to realize the voltage-controlled floating resistor, which is suitable for integrated circuit implementation. The proposed resistor is composed of three main components: MOS transistor operating in the non-saturation region, DDCC, and MOS voltage divider. The MOS transistor operating in the non-saturation region is used to configure a floating linear resistor. The DDCC and the MOS transistor voltage divider are used for canceling the nonlinear component term of MOS transistor in the non-saturation region to obtain a linear current/voltage relationship. The DDCC is employed to provide a simple summer of the circuit. This circuit offers an ease for realizing the voltage divider circuit and the temperature effect that includes in term of threshold voltage can be compensated. The proposed configuration employs only 16 MOS transistors. The performances of the proposed circuit are simulated with PSPICE to confirm the presented theory.

  9. Characterize the hydraulic behaviour of grate inlet in urban drainage to prevent the urban's flooding

    Science.gov (United States)

    Tellez Alvarez, Jackson David; Gomez, Manuel; Russo, Beniamino; Redondo, Jose M.

    2016-04-01

    image velocimetry to measure surface flow velocities has been developed and validated with the experiments assays with the grate inlets [3 - 4]. Indeed, the Methodology carried out can become a useful tools to understand the hydraulics behavior of the flow approaching the inlet where the traditional measuring equipment have serious problems and limitations [5 - 6]. References [1] Gómez, M., Macchione, F. and Russo, B. (2006). Inlet systems and risk criteria associated to street runoff application to urban drainage catchments. 27 Corso di aggiornamiento in techniche per la difesa dall'inquinamento. [2] Russo, B., Gómez, M., & Tellez, J. (2013). Methodology to Estimate the Hydraulic Efficiency of Nontested Continuous Transverse Grates. Journal of Irrigation and Drainage Engineering, 139(10), 864-871. doi:10.1061/(ASCE)IR.1943-4774.0000625 [3] DigiFlow. User Guide. (2012), (June). [4] Vila, T., Tellez, J., Sanchez, J.M., Sotillos, L., Diez, M., and Redondo, J.M. (2014). Diffusion in fractal wakes and convective thermoelectric flows. Geophysical Research Abstracts - EGU General Assembly 2014. [5] Tellez, J., Gómez, M., Russo, B. and Redondo, J.M. (2014). A simple technique to measuring surface flow velocity to analyze the behavior of fields velocities in hydraulics engineer applications. Geophysical Research Abstracts - EGU General Assembly 2015. [6] Tellez, J., Gómez, M. and Russo, B. (2015). Técnica para la obtención del campo de velocidad del flujo superficial en proximidad de rejas de alcantarillado. IV Jornadas de Ingeniería del Agua. La precipitación y los procesos erosivos.

  10. Programable Driver for Voltage-Controlled Oscillators

    Science.gov (United States)

    Fowler, L. E.; Mcneil, J. A.

    1985-01-01

    Electronically programable read-only memory (EPROM) and digital-to-analog converter provide customized time-varying voltage for frequency modulation. Voltage used to modulate IMPATT oscillator that serves as microwave pump for solid-state maser in low-noise amplifier. EPROM simple to tailor voltage waveform to suit characteristics of given maser. Digital information for waveform programed into EPROM chip; digital-to-analog converter reads information and produces corresponding analog wave. Principle readily adapted to other applications.

  11. Generator of ultrashort megavolt voltage pulses

    CERN Document Server

    Zheltov, K A; Shalimanov, V F

    2002-01-01

    Paper describes approx 3 ns duration and > 1 MW amplitude voltage pulse generator under high-ohmic (approx 450 Ohm) load. Generator comprises pulse transformer with magnetized core, as well as, resonance tuned circuit of high-voltage solenoid and accumulating spaces of a shaping line containing, moreover, spark gap to switch charge in transmitting line. Paper contains the results of voltage measuring in generator basic units

  12. Investigation of pulsed voltage limiters characteristics

    Directory of Open Access Journals (Sweden)

    Karimov A. V.

    2012-06-01

    Full Text Available A new method for measuring the voltage limit is offered. It has been designed to measure high-power pulsed current of voltage limiters. The error of this method is half as much as the error of the known method of direct measurement. The investigation of dependence of power capability of single-crystal and double-crystal voltage limiters and of the pulsed operation time on pulse duration.

  13. Nitrate removal from agricultural drainage ditch sediments with amendments of organic carbon: Potential for an innovative best management practice

    Science.gov (United States)

    Faust, Derek R.; Kröger, Robert; Miranda, Leandro E.; Rush, Scott A.

    2016-01-01

    Agricultural fertilizer applications have resulted in loading of nutrients to agricultural drainage ditches in the Lower Mississippi Alluvial Valley. The purpose of this study was to determine effects of dissolved organic carbon (DOC) and particulate organic carbon (POC) amendments on nitrate-nitrogen (NO3−-N) removal from overlying water, pore water, and sediment of an agricultural drainage ditch. Two experiments were conducted. In experiment 1, control (i.e., no amendment), DOC, and POC treatments were applied in laboratory microcosms for time intervals of 3, 7, 14, and 28 days. In experiment 2, control, DOC, and POC treatments were applied in microcosms at C/N ratios of 5:1, 10:1, 15:1, and 20:1. There were statistically significant effects of organic carbon amendments in experiment 1 (F2,71 = 27.1, P removal varied from 60 to 100 % in overlying water among all treatments. The lowest NO3−-N removals in experiment 1 were observed in the control at 14 and 28 days, which were significantly less than in DOC and POC 14- and 28-day treatments. In experiment 2, significantly less NO3−-N was removed in overlying water of the control compared to DOC and POC treatments at all C/N ratios. Amendments of DOC and POC made to drainage ditch sediment: (1) increased NO3−-N removal, especially over longer time intervals (14 to 28 days); (2) increased NO3−-N removal, regardless of C/N ratio; and (3) NO3−-N removal was best at a 5:1 C/N ratio. This study provides support for continued investigation on the use of organic carbon amendments as a best management practice for NO3−-N removal in agricultural drainage ditches.

  14. Low-Voltage Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Bidari, E.; Keskin, M.; Maloberti, F.

    1999-01-01

    Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications.......Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications....

  15. Characterisation of the VELO High Voltage System

    CERN Document Server

    Rakotomiaramanana, B; Eklund, L

    2008-01-01

    The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; vercation of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence th...

  16. Characterisation of the VELO High Voltage System

    CERN Document Server

    Rakotomiaramanana, B; Parkes, C; Eklund, L

    2008-01-01

    The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence...

  17. Microprocessor-controlled, programmable ramp voltage generator

    Energy Technology Data Exchange (ETDEWEB)

    Hopwood, J.

    1978-11-01

    A special-purpose voltage generator has been developed for driving the quadrupole mass filter of a residual gas analyzer. The generator is microprocessor-controlled with desired ramping parameters programmed by setting front-panel digital thumb switches. The start voltage, stop voltage, and time of each excursion are selectable. A maximum of five start-stop levels may be pre-selected for each program. The ramp voltage is 0 to 10 volts with sweep times from 0.1 to 999.99 seconds.

  18. Magnetoelectric voltage coefficients of magnetoelectric composites

    Institute of Scientific and Technical Information of China (English)

    WAN Yong-ping; ZHONG Zheng; QIU Jin-hao

    2006-01-01

    The magnetoelectric(ME) effect of the particulate magnetostrictive/piezoelectric composite was theoretically studied. The dependence of the ME voltage coefficients on the material properties of the magnetostrictive phase was discussed. The permittivity,permeability and the elastic modulus of the magnetostrictive phase generally have obvious influences on the ME voltage coefficients. The magnetostrictive phase with a large permittivity,large permeability or stiffer modulus will respectively contribute to the higher ME voltage coefficients. For a certain kind of piezoelectric matrix,the ME voltage coefficients can be improved to some extent by choosing those magnetostrictive materials with large permittivity,permeability or high elastic modulus.

  19. Inductive voltage divider modeling in Matlab

    Science.gov (United States)

    Andreev, S. A.; Kim, V. L.

    2017-01-01

    Inductive voltage dividers have the most appropriate metrological characteristics on alternative current and are widely used for converting physical signals. The model of a double-decade inductive voltage divider was designed with the help of Matlab/Simulink. The first decade is an inductive voltage divider with balanced winding, the second decade is a single-stage inductive voltage divider. In the paper, a new transfer function algorithm was given. The study shows errors and differences that appeared between the third degree reduced model and a twenty degree unreduced model. The obtained results of amplitude error differ no more than by 7 % between the reduced and unreduced model.

  20. Development of a voltage scanner of chopper

    CERN Document Server

    Shen Guan Ren; LiShengLi; WangQuanXing; Wu Long Cheng

    2001-01-01

    Development of voltage sweeper of chopper with CPNG are introduced. Voltage sweeper is one of important key parts of chopper. Two years working prove that it is stable and reliable. Its main technology performance save: sine wave frequency: 750 kHz +- 20 Hz; total distortion: 65 Db; output voltage (V-V): 0->=4000 V; the error7 W; voltage supply: 220V AC +-10%, 50 +- 1 Hz; total power supply: <100W; Work temperature range: 0 - 40 degree; Stability in long time <=1%

  1. Efficiency of lachrymal sac drainage in newborns with dacryocystocele

    Directory of Open Access Journals (Sweden)

    Sakovich V.N.

    2016-12-01

    Full Text Available The article represents results of treatment of 14 newborns with unilateral dacryocystocele. Patients age was 7.2±0.5 days. In 9 newborns (64.3% dacryocystocele was complicated with lachrymal sac phlegmon; in 5 children (35.7% any complications were absent. Drainage of lachrymal sac through the lower lachrymal canaliculus, instillation of antibiotics, systemic antibiotic therapy in case of phlegmon were performed in all the children. Lachrymal sac washing was performed with a solution of the antibiotic ofloxacin till clear fluid evacuation. If necessary the drainage was repeated in 10 days. The drainage of lachrymal sac was successful in all the patients. 2-3 weeks after the drainage probing of nasolachrymal duct was perfomed in 4 children (28.6% including those 3 with lacrymal sac phlegmon. In 71.4% regression of dacryocystocele occurred itself. Any complications and side effects were not observed. Positive effect of the drainage, according to the authors, can be explained so that dilatation of lachrymal canaliculus before the procedure allows to eliminate Rosenmьller valve stenosis and evacuation of fluid, mucus and pus, being breeding ground for microorganisms from lachrymal sac, promotes inflammation subsiding. Authors also recommend to pay attention on prenatal diagnosis of dacryocystocele, using ultrasound investigation in the 3rd trimester of pregnancy.

  2. Bubble motion measurements during foam drainage and coarsening.

    Science.gov (United States)

    Maurdev, G; Saint-Jalmes, A; Langevin, D

    2006-08-15

    We have studied bubble motion within a column of foam allowed to undergo free drainage. We have measured bubble motion upward with time and as a function of their initial positions. Depending on the gas used, which sets the coarsening and drainage rates, different bubble upward motion types have been identified (constant speed, acceleration or deceleration) and explained in relation with liquid downward flows. The proofs of the consistency between bubble upward motion and liquid downward flow are obtained both by comparing the bubble motion curves to the liquid drainage ones, and by comparing the time variations of the liquid fraction extracted from bubble motion to direct liquid fraction measurements by electrical conductimetry. The agreement between bubble position tracking and electrical conductivity shows in particular that it is possible to determine the drainage regime from such simple bubble motion measurements. This work also allowed us to demonstrate a special case of foam coarsening and expansion, occurring when the foam gas is less soluble than the outside one, caused by diffusion of this external gas into the foam. All these results allow us to build a picture of drainage and coarsening seen from the bubble point of view.

  3. Management of chest drainage tubes after lung surgery.

    Science.gov (United States)

    Satoh, Yukitoshi

    2016-06-01

    Since chest tubes have been routinely used to drain the pleural space, particularly after lung surgery, the management of chest tubes is considered to be essential for the thoracic surgeon. The pleural drainage system requires effective drainage, suction, and water-sealing. Another key point of chest tube management is that a water seal is considered to be superior to suction for most air leaks. Nowadays, the most common pleural drainage device attached to the chest tube is the three-bottle system. An electronic chest drainage system has been developed that is effective in standardizing the postoperative management of chest tubes. More liberal use of digital drainage devices in the postoperative management of the pleural space is warranted. The removal of chest tubes is a common procedure occurring almost daily in hospitals throughout the world. Extraction of the tube is usually done at the end of full inspiration or at the end of full expiration. The tube removal technique is not as important as how it is done and the preparation for the procedure. The management of chest tubes must be based on careful observation, the patient's characteristics, and the operative procedures that had been performed.

  4. Right Gastric Venous Drainage: Angiographic Analysis in 100 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Nak Jong [Seoul National University Bundang Hospital, Sungnam (Korea, Republic of); Chung, Jin Wook; Kim, Hyo Cheol; Park, Jae Hyung; Jae, Hwan Jun [Seoul National University Hospital, Seoul (Korea, Republic of); An, Sang Bu [National Cancer Center, Ilsan (Korea, Republic of); Cho, Baik Hwan [Chonbuk National University Hospital, Chonju (Korea, Republic of)

    2012-01-15

    To evaluate the pattern of right gastric venous drainage by use of digital subtraction angiography. A series of 100 consecutive patients who underwent right gastric arteriography during transcatheter arterial chemoembolization for hepatocellular carcinoma were included in this study. Angiographic findings were retrospectively analyzed with respect to the presence or absence of the right and aberrant gastric veins, multiplicity of draining veins, aberrant right gastric venous drainage sites, and the termination pattern of aberrant right gastric veins (ARGVs). We also compared the relative size of the right and left gastric veins. A total of 49 patients collectively had 66 ARGVs. The common drainage sites for the ARGVs included the hepatic segment IV (n = 35) and segment I (n = 15). The termination pattern of ARGV could be classified into 4 different types. The most common type was termination as a superficial parenchymal blush formation in small areas without demonstrable portal branches. A statistically significant difference was found for the dominance of the right gastric vein in gastric venous drainage between the two groups with or without ARGV (p < 0.05, Fisher's exact test). In the group of patients without ARGV (n = 51), the right gastric vein was equal to (n = 9) or larger than (n = 17) the left gastric vein in 26 patients (26 of 51, 51%). The incidence of ARGV is higher than expected with four distinct types in its termination pattern. The right gastric vein may play a dominant role in gastric venous drainage.

  5. Current status of preoperative drainage for distal biliary obstruction

    Institute of Scientific and Technical Information of China (English)

    Harutoshi; Sugiyama; Toshio; Tsuyuguchi; Yuji; Sakai; Rintaro; Mikata; Shin; Yasui; Yuto; Watanabe; Dai; Sakamoto; Masato; Nakamura; Reina; Sasaki; Jun-ichi; Senoo; Yuko; Kusakabe; Masahiro; Hayashi; Osamu; Yokosuka

    2015-01-01

    Preoperative biliary drainage(PBD) was developed to improve obstructive jaundice, which affects a number of organs and physiological mechanisms in patients waiting for surgery. However, its role in patients who will undergo pancreaticoduodenectomy for biliary obstruction remains controversial. This article aims to review the current status of the use of preoperative drainage for distal biliary obstruction. Relevant articles published from 1980 to 2015 were identified by searching MEDLINE and Pub Med using the keywords "PBD", "pancreaticoduodenectomy", and "obstructive jaundice". Additional papers were identified by a manual search of the references from key articles. Current studies have demonstrated that PBD should not be routinely performed because of the postoperative complications. PBD should only be considered in carefully selected patients, particularly in cases where surgery had to be delayed. PBD may be needed in patients with severe jaundice, concomitant cholangitis, or severe malnutrition. The optimal method of biliary drainage has yet to be confirmed. PBD should be performed by endoscopic routes rather than by percutaneous routes to avoid metastatic tumor seeding. Endoscopic stenting or nasobiliary drainage can be selected. Although more expensive, the use of metallic stents remains a viable option to achieve effective drainage without cholangitis and reintervention.

  6. Connected subglacial lake drainage beneath Thwaites Glacier, West Antarctica

    Science.gov (United States)

    Smith, Benjamin E.; Gourmelen, Noel; Huth, Alexander; Joughin, Ian

    2017-02-01

    We present conventional and swath altimetry data from CryoSat-2, revealing a system of subglacial lakes that drained between June 2013 and January 2014 under the central part of Thwaites Glacier, West Antarctica (TWG). Much of the drainage happened in less than 6 months, with an apparent connection between three lakes spanning more than 130 km. Hydro-potential analysis of the glacier bed shows a large number of small closed basins that should trap water produced by subglacial melt, although the observed large-scale motion of water suggests that water can sometimes locally move against the apparent potential gradient, at least during lake-drainage events. This shows that there are important limitations in the ability of hydro-potential maps to predict subglacial water flow. An interpretation based on a map of the melt rate suggests that lake drainages of this type should take place every 20-80 years, depending on the connectivity of the water flow at the bed. Although we observed an acceleration in the downstream part of TWG immediately before the start of the lake drainage, there is no clear connection between the drainage and any speed change of the glacier.

  7. Excitation of voltage oscillations in an induction voltage adder

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2009-07-01

    Full Text Available The induction voltage adder is an accelerator architecture used in recent designs of pulsed-power driven x-ray radiographic systems such as Sandia National Laboratories’ Radiographic Integrated Test Stand (RITS, the Atomic Weapons Establishment’s planned Hydrus Facility, and the Naval Research Laboratory’s Mercury. Each of these designs relies on magnetic insulation to prevent electron loss across the anode-cathode gap in the vicinity of the adder as well as in the coaxial transmission line. Particle-in-cell simulations of the RITS adder and transmission line show that, as magnetic insulation is being established during a pulse, some electron loss occurs across the gap. Sufficient delay in the cavity pulse timings provides an opportunity for high-momentum electrons to deeply penetrate the cavities of the adder cells where they can excite radio-frequency resonances. These oscillations may be amplified in subsequent gaps, resulting in oscillations in the output power. The specific modes supported by the RITS-6 accelerator and details of the mechanism by which they are excited are presented in this paper.

  8. Disinfecting greenhouse drainage with solar energy; Desinfeccion de drenaje de invernaderos con energia solar

    Energy Technology Data Exchange (ETDEWEB)

    Camara Zapata, J. M.; Puerto Molina, H. M.

    2004-07-01

    This work shows the results of three experiments made with a thermal solar collector for disinfecting greenhouse drainage water in Orihuela (SE of Spain). The aim was to evaluate the influence of water volume to be treated on the thermal efficiency of the collector. The results show a reduction of both, the collector's optic efficiency and the losses coefficient, with increasing volumes of the treated water. Both parameters have opposite effects on the thermal efficiency of the collector. In our experimental conditions, the optimum thermal efficiency was obtained for a water-to-air temperature difference of 16 degree Centigree independently of the treated water volume. (Author)

  9. Deformation of an experimental drainage network in oblique collision

    Science.gov (United States)

    Guerit, L.; Dominguez, S.; Malavieille, J.; Castelltort, S.

    2016-12-01

    In oblique collision settings, parallel and perpendicular components of the relative plate motion can be partitioned into different structures of deformation and may be localized close to the plate boundary, or distributed on a wider region. In the Southern Alps of New Zealand, it has been proposed that one-third of the regional convergence is distributed in a broad area along the Southern Alps orogenic wedge. To better document and understand the regional dynamics of such systems, reliable markers of the horizontal tectonic motion over geological time scales are needed. River networks are able to record a large amount of distributed strain and they can thus be used to reconstruct the mode and rate of distribution away from major active structures. To explore the controls on river resilience to deformation, we develop an experimental model to investigate river pattern evolution over a doubly-vergent orogenic wedge growing in a context of oblique convergence. We use a rainfall system to activate erosion, sediment transport and river development on the model surface. At the end of the experiment, the drainage network is statistically rotated clockwise, confirming that rivers can record the distribution of motion along the wedge. Image analysis of channel time-space evolution shows how the fault-parallel and fault-perpendicular components of motion decrease toward the fault and impose rotation to the main trunk valleys. However, rivers do not record the whole imposed rotation rate, which suggest that the natural lateral channel dynamics can alter the capacity of rivers to act as passive markers of deformation.

  10. Teaching Incision and Drainage: Perceived Educational Value of Abscess Models.

    Science.gov (United States)

    Adams, Cynthia M; Nigrovic, Lise E; Hayes, Gavin; Weinstock, Peter H; Nagler, Joshua

    2017-07-17

    Incision and drainage (I&D) of skin abscesses is an important procedural skill for pediatric emergency medicine providers. Practical skills training using simulation provides an opportunity to learn and gain confidence with this invasive procedure. Our objective was to assess the perceived educational value of 2 versions of an abscess model as part of an educational workshop for teaching I&D. A combined didactic and practical skills workshop was developed for use at 2 national conferences. The didactic content was created through an iterative process. To facilitate hands-on training, 2 versions of an abscess model were created: 1 constructed from a negative mold and the other using a 3-dimensional printer. Participants were surveyed regarding prior experience with I&D, procedural confidence, and perceptions of the educational utility of the models. Seventy physicians and 75 nurse practitioners participated in the study. Procedural confidence improved after training using each version of the model, with the greatest improvements noted among novice learners. Ninety-four percent of physicians, and 99% of nurse practitioners rated the respective models as either "educational" or "very educational," and 97% and 100%, respectively, would recommend the abscess models to others. A combined didactic and practical skills educational workshop using novel abscess models was effective at improving learners' confidence. Our novel models provide an effective strategy for teaching procedural skills such as I&D and demonstrate a novel use of 3-dimensional printers in medical education. Further study is needed to determine if these educational gains translate into improvement in clinical performance or patient outcomes.

  11. Electron bunch structure in energy recovery linac with high-voltage dc photoelectron gun

    Science.gov (United States)

    Saveliev, Y. M.; Jackson, F.; Jones, J. K.; McKenzie, J. W.

    2016-09-01

    The internal structure of electron bunches generated in an injector line with a dc photoelectron gun is investigated. Experiments were conducted on the ALICE (accelerators and lasers in combined experiments) energy recovery linac at Daresbury Laboratory. At a relatively low dc gun voltage of 230 kV, the bunch normally consisted of two beamlets with different electron energies, as well as transverse and longitudinal characteristics. The beamlets are formed at the head and the tail of the bunch. At a higher gun voltage of 325 kV, the beam substructure is much less pronounced and could be observed only at nonoptimal injector settings. Experiments and computer simulations demonstrated that the bunch structure develops during the initial beam acceleration in the superconducting rf booster cavity and can be alleviated either by increasing the gun voltage to the highest possible level or by controlling the beam acceleration from the gun voltage in the first accelerating structure.

  12. Next generation KATRIN high precision voltage divider for voltages up to 65kV

    CERN Document Server

    Bauer, S; Hochschulz, F; Ortjohann, H -W; Rosendahl, S; Thümmler, T; Schmidt, M; Weinheimer, C

    2013-01-01

    The KATRIN (KArlsruhe TRItium Neutrino) experiment aims to determine the mass of the electron antineutrino with a sensitivity of 200meV by precisely measuring the electron spectrum of the tritium beta decay. This will be done by the use of a retarding spectrometer of the MAC-E-Filter type. To achieve the desired sensitivity the stability of the retarding potential of -18.6kV has to be monitored with a precision of 3ppm over at least two months. Since this is not feasible with commercial devices, two ppm-class high voltage dividers were developed, following the concept of the standard divider for DC voltages of up to 100kV of the Physikalisch-Technische Bundesanstalt (PTB). In order to reach such high accuracies different effects have to be considered. The two most important ones are the temperature dependence of resistance and leakage currents, caused by insulators or corona discharges. For the second divider improvements were made concerning the high-precision resistors and the thermal design of the divider....

  13. Multimeric nature of voltage-gated proton channels.

    Science.gov (United States)

    Koch, Hans P; Kurokawa, Tatsuki; Okochi, Yoshifumi; Sasaki, Mari; Okamura, Yasushi; Larsson, H Peter

    2008-07-01

    Voltage-gated potassium channels are comprised of four subunits, and each subunit has a pore domain and a voltage-sensing domain (VSD). The four pore domains assemble to form one single central pore, and the four individual VSDs control the gate of the pore. Recently, a family of voltage-gated proton channels, such as H(V) or voltage sensor only protein (VSOP), was discovered that contain a single VSD but no pore domain. It has been assumed that VSOP channels are monomeric and contain a single VSD that functions as both the VSD and the pore domain. It remains unclear, however, how a protein that contains only a VSD and no pore domain can conduct ions. Using fluorescence measurements and immunoprecipitation techniques, we show here that VSOP channels are expressed as multimeric channels. Further, FRET experiments on constructs with covalently linked subunits show that VSOP channels are dimers. Truncation of the cytoplasmic regions of VSOP reduced the dimerization, suggesting that the dimerization is caused mainly by cytoplasmic protein-protein interactions. However, these N terminus- and C terminus-deleted channels displayed large proton currents. Therefore, we conclude that even though VSOP channels are expressed mainly as dimers in the cell membrane, single VSOP subunits could function independently as proton channels.

  14. Voltage-Independent Calcium Release in Heart Muscle

    Science.gov (United States)

    Niggli, Ernst; Lederer, W. Jonathan

    1990-10-01

    The Ca2+ that activates contraction in heart muscle is regulated as in skeletal muscle by processes that depend on voltage and intracellular Ca2+ and involve a positive feedback system. How the initial electrical signal is amplified in heart muscle has remained controversial, however. Analogous protein structures from skeletal muscle and heart muscle have been identified physiologically and sequenced; these include the Ca2+ channel of the sarcolemma and the Ca2+ release channel of the sarcoplasmic reticulum. Although the parallels found in cardiac and skeletal muscles have provoked valuable experiments in both tissues, separation of the effects of voltage and intracellular Ca2+ on sarcoplasmic reticulum Ca2+ release in heart muscle has been imperfect. With the use of caged Ca2+ and flash photolysis in voltage-clamped heart myocytes, effects of membrane potential in heart muscle cells on Ca2+ release from intracellular stores have been studied. Unlike the response in skeletal muscle, voltage across the sarcolemma of heart muscle does not affect the release of Ca2+ from the sarcoplasmic reticulum, suggesting that other regulatory processes are needed to control Ca2+-induced Ca2+ release.

  15. A Synchrophasor Based Optimal Voltage Control Scheme with Successive Voltage Stability Margin Improvement

    Directory of Open Access Journals (Sweden)

    Heng-Yi Su

    2016-01-01

    Full Text Available This paper proposes an optimal control scheme based on a synchronized phasor (synchrophasor for power system secondary voltage control. The framework covers voltage stability monitoring and control. Specifically, a voltage stability margin estimation algorithm is developed and built in the newly designed adaptive secondary voltage control (ASVC method to achieve more reliable and efficient voltage regulation in power systems. This new approach is applied to improve voltage profile across the entire power grid by an optimized plan for VAR (reactive power sources allocation; therefore, voltage stability margin of a power system can be increased to reduce the risk of voltage collapse. An extensive simulation study on the IEEE 30-bus test system is carried out to demonstrate the feasibility and effectiveness of the proposed scheme.

  16. Industrial Flow Designing of Dried Mud Drainage for Flush Fluid in Pingguo Aluminum

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Because there are plenty of clay particles in the flush fluid of Pingguo Aluminum Mine, the consolidation technology in geotechnical engineering was adopted to carry out the disassociation of water and soil disassociation. In this method, vacuum method, electro-osmosis and chemical flocculation were used comprehensively to separate soil from flush fluid. The experiments of the method of "vacuum + electro-osmosis" for drainage was made. After pretreating the flush fluid, suction pressure was offered by the sand well in the bottom and electro-osmosis was used to drain off water. The results of the experiment show that the good effect can be obtained in drainage when the electric gradient is greater than 8.3 V/cm and the quantity of sand well is more than 6. In industrial production, it is necessary to increase the quantity of sand well, to arrange the electrodes rationally and to set up an intermittent electric circuit. On the basis of the experiments , the industrial feasible flow was put forward. It may be a helpful attempt to apply consolidation technology to the fields of the environmental protection and so on.

  17. Evaluation of the Voltage Support Strategies for the Low Voltage Grid Connected PV

    DEFF Research Database (Denmark)

    Demirok, Erhan; Sera, Dezso; Teodorescu, Remus

    2010-01-01

    PVs. In order to increase PV penetration level further, new voltage support control functions for individual inverters are required. This paper investigates distributed reactive power regulation and active power curtailment strategies regarding the development of PV connection capacity by evaluation......Admissible range of grid voltage is one of the strictest constraints for the penetration of distributed photovoltaic (PV) generators especially connection to low voltage (LV) public networks. Voltage limits are usually fulfilled either by network reinforcements or limiting of power injections from...

  18. Evaluation of the sustainability of road drainage systems

    Science.gov (United States)

    García-Diez, Iván; Palencia, Covadonga; Fernández Raga, María

    2017-04-01

    Water is the most erosive agent that exists on the linear structures, because they are constantly subjected to outdoor condition like irregular infiltration, frosts and different rain intensities. Another variables that highly influence in the entire lifetime of a natural drainage system are the spatial and temporal variability of the rainfall, the soil, the vegetation cover and the design. All this factors are affecting the vulnerability of the clearings and embankments, by wearing away the weakest materials which surround the roads or train rails, producing erosion and very bumpy surfaces. The result is that the original pattern, developped to disminished the lost of soil, is not properly working and it cannot eliminate water, with the consequence destruction of the linear structure after several rainfall periods, and the accumulation of material down slope. The propose of this research focuses on analysing the drainage systems used in spanish roads and railways lines. For this purpose, a revision of the literature has been done, and the main drainage solutions have been recovered, carrying out an evaluation of them from an environmental point of view. This procedure has been requested by several authors in the past (Nwa, E.U. & Twocock, J.G., 1969; Goulter, I.C., 1992), together with the need of designing a more sustainable drainage system. The final objective of this complete revision is to compare objetively the designs to valuate them in order to develop a new drainage patter which minimize the erosion, increasing the durability and effectiveness of the drainage system. For this purpose, it is neccesary to assure that all the systems will be compare under similar parameters of flow rate, vegetation, substrate, lenght, slope and total section. Only the channels pattern and water distribution will change. The analysis has been done following Liu, H. & Zhu, X.B., (2012), who pointed out that the main parameters to take into account to select a road drainage

  19. Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages

    Science.gov (United States)

    de Carvalho Filho, Élio Barreto; Marson, Fernando Augusto de Lima; da Costa, Loredana Nilkenes Gomes; Antunes, Nilson

    2014-01-01

    Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas. PMID:25140478

  20. Urban Drainage System Improvement for Climate Change Adaptation

    Directory of Open Access Journals (Sweden)

    Narae Kang

    2016-06-01

    Full Text Available Recently, urban areas have experienced frequent, large-scale flooding, a situation that has been aggravated by climate change. This study aims to improve the urban drainage system to facilitate climate change adaptation. A methodology and a series of mitigation strategies are presented to efficiently improve the urban drainage system in light of climate change. In addition, we assess the impact of climate change and predict the scale of potential future flood damage by applying the methodology and mitigation strategies to urban areas. Based on the methodology presented, urban flood prevention measures for Gyeyang-gu (Province, Incheon, Korea, was established. The validity of the proposed alternatives is verified by assessing the economic feasibility of the projects to reduce flood damage. We expect that the methodology presented will aid the decision-making process and assist in the development of reasonable strategies to improve the urban drainage system for adaptation to climate change.

  1. Electronic versus traditional chest tube drainage following lobectomy

    DEFF Research Database (Denmark)

    Lijkendijk, Marike; Licht, Peter B; Neckelmann, Kirsten

    2015-01-01

    OBJECTIVES: Electronic drainage systems have shown superiority compared with traditional (water seal) drainage systems following lung resections, but the number of studies is limited. As part of a medico-technical evaluation, before change of practice to electronic drainage systems for routine...... thoracic surgery, we conducted a randomized controlled trial (RCT) investigating chest tube duration and length of hospitalization. METHODS: Patients undergoing lobectomy were included in a prospective open label RCT. A strict algorithm was designed for early chest tube removal, and this decision...... time for chest tube removal, as well as length of hospitalization. RESULTS: A total of 105 patients were randomized. We found no significant difference between the electronic group and traditional group in optimal chest tube duration (HR = 0.83; 95% CI: 0.55-1.25; P = 0.367), actual chest tube duration...

  2. A new thermogeomechanical theory for gravity drainage in SAGD

    Energy Technology Data Exchange (ETDEWEB)

    Cokar, M.; Kallos, M.S.; Gates, I.D. [Dept. of Chemical and Petroleum Engineering, University of Calgary (Canada)

    2011-07-01

    In the heavy oil and bitumen industry, the steam assisted gravity drainage (SAGD) process is often used to enhance oil recovery. In such deposits, oil usually has no mobility due to its high viscosity and the injection of steam leads to an increase in the mobility of bitumen. Since the thermogeomechanical evolution of the oil sand at the chamber edge is important to the SAGD's performance, this paper aimed at taking these effects into account in a new SAGD drainage formula. The SAGD theory was modified to incorporate the effects of geomechanics and the results were then compared with Butler's model and the Sharma and Gates model. Results showed that thermal expansion has an important impact on oil rates and that geomechanical effects need to be considered when analysing the flow at the edge of steam chambers. This study developed a SAGD drainage formula and demonstrated the importance of geomechanics in the SAGD's performance.

  3. Gas drainage management systems for modern coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Creedy, D.; Lunarzewski, L. [Wardell Armstrong, Newcastle-under-Lyme (United Kingdom)

    2001-07-01

    Gas emission and outburst problems remain one of the major difficulties facing the world coal mining industry. Methane emission in coal mines adversely affects the efficiency of coal production and mine safety conditions. Risk can be reduced by gas drainage. The methane thus recovered is a potentially valuable energy source which if used can produce both financial and environmental benefits. The generic gas control methods of gas drainage and ventilation are common to most coal mining countries but the detailed technologies applied differ according to the geological, mining and economic conditions, and also with the magnitudes of coal production. However, the critical element of all gas drainage management systems is the management organisation which ensures allocation of responsibility and provides a systematic framework for effective application of the most appropriate technology. 8 refs., 6 figs., 1 tab.

  4. Voltage threshold behaviors of ZnO nanorod doped liquid crystal cell

    Institute of Scientific and Technical Information of China (English)

    Guo Yubing; Chen Yonghai; Xiang Ying; and Qu Shengchun

    2011-01-01

    With ZnO nanorods doped in only one poly (vinyl alcohol) (PVA) layer,we observed different threshold voltages with reverse DC voltages for a liquid crystal cell.The length and diameter of the ZnO nanorod used in our experiment were about 180 nm and 20 nm,respectively.When the PVA layer on the anodic side was doped,the threshold voltage was larger than that of the pure cell; conversely,when the PVA layer on the cathodic side was doped,the threshold voltage was smaller than that of the pure cell.These results can be explained by the internal electric field model.We also observed a resonance phenomenon with a low frequency AC voltage.

  5. Analysis of trigger behavior of high voltage LDMOS under TLP and VFTLP stress

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Jing; Qian Qinsong; Sun Weifeng; Liu Siyang, E-mail: zhj_seu@126.co [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)

    2010-01-15

    The physical mechanisms triggering electrostatic discharge (ESD) in high voltage LDMOS power transistors (> 160 V) under transmission line pulsing (TLP) and very fast transmission line pulsing (VFTLP) stress are investigated by TCAD simulations using a set of macroscopic physical models related to previous studies implemented in Sentaurus Device. Under VFTLP stress, it is observed that the triggering voltage of the high voltage LDMOS obviously increases, which is a unique phenomenon compared with the low voltage ESD protection devices like NMOS and SCR. The relationship between the triggering voltage increase and the parasitic capacitances is also analyzed in detail. A compact equivalent circuit schematic is presented according to the investigated phenomena. An improved structure to alleviate this effect is also proposed and confirmed by the experiments. (semiconductor devices)

  6. Exocrine drainage in vascularized pancreas transplantation in the new millennium

    Science.gov (United States)

    El-Hennawy, Hany; Stratta, Robert J; Smith, Fowler

    2016-01-01

    The history of vascularized pancreas transplantation largely parallels developments in immunosuppression and technical refinements in transplant surgery. From the late-1980s to 1995, most pancreas transplants were whole organ pancreatic grafts with insulin delivery to the iliac vein and diversion of the pancreatic ductal secretions to the urinary bladder (systemic-bladder technique). The advent of bladder drainage revolutionized the safety and improved the success of pancreas transplantation. However, starting in 1995, a seismic change occurred from bladder to bowel exocrine drainage coincident with improvements in immunosuppression, preservation techniques, diagnostic monitoring, general medical care, and the success and frequency of enteric conversion. In the new millennium, pancreas transplants are performed predominantly as pancreatico-duodenal grafts with enteric diversion of the pancreatic ductal secretions coupled with iliac vein provision of insulin (systemic-enteric technique) although the systemic-bladder technique endures as a preferred alternative in selected cases. In the early 1990s, a novel technique of venous drainage into the superior mesenteric vein combined with bowel exocrine diversion (portal-enteric technique) was designed and subsequently refined over the next ≥ 20 years to re-create the natural physiology of the pancreas with first-pass hepatic processing of insulin. Enteric drainage usually refers to jejunal or ileal diversion of the exocrine secretions either with a primary enteric anastomosis or with an additional Roux limb. The portal-enteric technique has spawned a number of newer and revisited techniques of enteric exocrine drainage including duodenal or gastric diversion. Reports in the literature suggest no differences in pancreas transplant outcomes irrespective of type of either venous or exocrine diversion. The purpose of this review is to examine the literature on exocrine drainage in the new millennium (the purported

  7. Implementation of a drainage information, analysis and management system

    Directory of Open Access Journals (Sweden)

    J.N. Meegoda

    2017-04-01

    Full Text Available An integrated drainage information, analysis and management system (DIAMS was developed and implemented for the New Jersey Department of Transportation (NJDOT. The purpose of the DIAMS is to provide a useful tool for managers to evaluate drainage infrastructure, to facilitate the determination of the present costs of preserving those infrastructures, and to make decisions regarding the optimal use of their infrastructure budgets. The impetus for DIAMS is the culvert information management system (CIMS, which is developed to manage the data for culvert pipes. DIAMS maintains and summarizes accumulated inspection data for all types of drainage infrastructure assets, including pipes, inlet/outlet structures, outfalls and manufactured treatment devices. DIAMS capabilities include identifying drainage infrastructure, maintaining inspection history, mapping locations, predicting service life based on the current condition states, and assessing present asset value. It also includes unit cost values of 72 standard items to estimate the current cost for new assets with the ability to adjust for future inflation. In addition, DIAMS contains several different repair, rehabilitation and replacement options to remedy the drainage infrastructure. DIAMS can analyze asset information and determine decisions to inspect, rehabilitate, replace or do nothing at the project and network levels by comparing costs with risks and failures. Costs may be optimized to meet annual maintenance budget allocations by prioritizing drainage infrastructure needing inspection, cleaning and repair. DIAMS functional modules include vendor data uploading, asset identification, system administration and financial analysis. Among the significant performance feature of DIAMS is its proactive nature, which affords decision makers the means of conducting a comprehensive financial analysis to determine the optimal proactive schedule for the proper maintenance actions and to prioritize them

  8. Influence of current limitation on voltage stability with voltage sourced converter HVDC

    DEFF Research Database (Denmark)

    Zeni, Lorenzo; Jóhannsson, Hjörtur; Hansen, Anca Daniela;

    2013-01-01

    A first study of voltage stability with relevant amount of Voltage Sourced Converter based High Voltage Direct Current (VSC-HVDC) transmission is presented, with particular focus on the converters’ behaviour when reaching their rated current. The detrimental effect of entering the current...

  9. Voltage stability in low voltage microgrids in aspects of active and reactive power demand

    Directory of Open Access Journals (Sweden)

    Parol Mirosław

    2016-03-01

    Full Text Available Low voltage microgrids are autonomous subsystems, in which generation, storage and power and electrical energy consumption appear. In the paper the main attention has been paid to the voltage stability issue in low voltage microgrid for different variants of its operation. In the introduction a notion of microgrid has been presented, and also the issue of influence of active and reactive power balance on node voltage level has been described. Then description of voltage stability issue has been presented. The conditions of voltage stability and indicators used to determine voltage stability margin in the microgrid have been described. Description of the low voltage test microgrid, as well as research methodology along with definition of considered variants of its operation have been presented further. The results of exemplary calculations carried out for the daily changes in node load of the active and reactive power, i.e. the voltage and the voltage stability margin indexes in nodes have been presented. Furthermore, the changes of voltage stability margin indexes depending on the variant of the microgrid operation have been presented. Summary and formulation of conclusions related to the issue of voltage stability in microgrids have been included at the end of the paper.

  10. Reduced Voltage Scaling in Clock Distribution Networks

    Directory of Open Access Journals (Sweden)

    Khader Mohammad

    2009-01-01

    Full Text Available We propose a novel circuit technique to generate a reduced voltage swing (RVS signals for active power reduction on main buses and clocks. This is achieved without performance degradation, without extra power supply requirement, and with minimum area overhead. The technique stops the discharge path on the net that is swinging low at a certain voltage value. It reduces active power on the target net by as much as 33% compared to traditional full swing signaling. The logic 0 voltage value is programmable through control bits. If desired, the reduced-swing mode can also be disabled. The approach assumes that the logic 0 voltage value is always less than the threshold voltage of the nMOS receivers, which eliminate the need of the low to high voltage translation. The reduced noise margin and the increased leakage on the receiver transistors using this approach have been addressed through the selective usage of multithreshold voltage (MTV devices and the programmability of the low voltage value.

  11. Low-Voltage Continuous Electrospinning Patterning.

    Science.gov (United States)

    Li, Xia; Li, Zhaoying; Wang, Liyun; Ma, Guokun; Meng, Fanlong; Pritchard, Robyn H; Gill, Elisabeth L; Liu, Ye; Huang, Yan Yan Shery

    2016-11-30

    Electrospinning is a versatile technique for the construction of microfibrous and nanofibrous structures with considerable potential in applications ranging from textile manufacturing to tissue engineering scaffolds. In the simplest form, electrospinning uses a high voltage of tens of thousands volts to draw out ultrafine polymer fibers over a large distance. However, the high voltage limits the flexible combination of material selection, deposition substrate, and control of patterns. Prior studies show that by performing electrospinning with a well-defined "near-field" condition, the operation voltage can be decreased to the kilovolt range, and further enable more precise patterning of fibril structures on a planar surface. In this work, by using solution dependent "initiators", we demonstrate a further lowering of voltage with an ultralow voltage continuous electrospinning patterning (LEP) technique, which reduces the applied voltage threshold to as low as 50 V, simultaneously permitting direct fiber patterning. The versatility of LEP is shown using a wide range of combination of polymer and solvent systems for thermoplastics and biopolymers. Novel functionalities are also incorporated when a low voltage mode is used in place of a high voltage mode, such as direct printing of living bacteria; the construction of suspended single fibers and membrane networks. The LEP technique reported here should open up new avenues in the patterning of bioelements and free-form nano- to microscale fibrous structures.

  12. Modeling and Simulation of Low Voltage Arcs

    NARCIS (Netherlands)

    Ghezzi, L.; Balestrero, A.

    2010-01-01

    Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical

  13. High-voltage engineering and testing

    CERN Document Server

    Ryan, Hugh M

    2013-01-01

    This 3rd edition of High Voltage Engineering Testing describes strategic developments in the field and reflects on how they can best be managed. All the key components of high voltage and distribution systems are covered including electric power networks, UHV and HV. Distribution systems including HVDC and power electronic systems are also considered.

  14. Modeling and Simulation of Low Voltage Arcs

    NARCIS (Netherlands)

    Ghezzi, L.; Balestrero, A.

    2010-01-01

    Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical m

  15. Voltage-gated lipid ion channels

    DEFF Research Database (Denmark)

    Blicher, Andreas; Heimburg, Thomas Rainer

    2013-01-01

    Synthetic lipid membranes can display channel-like ion conduction events even in the absence of proteins. We show here that these events are voltage-gated with a quadratic voltage dependence as expected from electrostatic theory of capacitors. To this end, we recorded channel traces and current...

  16. Routine abdominal drainage versus no abdominal drainage for uncomplicated laparoscopic cholecystectomy.

    Science.gov (United States)

    Gurusamy, Kurinchi Selvan; Koti, Rahul; Davidson, Brian R

    2013-09-03

    Laparoscopic cholecystectomy is the main method of treatment of symptomatic gallstones. Drains are used after laparoscopic cholecystectomy to prevent abdominal collections. However, drain use may increase infective complications and delay discharge. The aim is to assess the benefits and harms of routine abdominal drainage in uncomplicated laparoscopic cholecystectomy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until February 2013. We included all randomised clinical trials comparing drainage versus no drainage after uncomplicated laparoscopic cholecystectomy irrespective of language and publication status. We used standard methodological procedures defined by The Cochrane Collaboration. A total of 1831 participants were randomised to drain (915 participants) versus 'no drain' (916 participants) in 12 trials included in this review. Only two trials including 199 participants were of low risk of bias. Nine trials included patients undergoing elective laparoscopic cholecystectomy exclusively. One trial included patients undergoing laparoscopic cholecystectomy for acute cholecystitis exclusively. One trial included patients undergoing elective and emergency laparoscopic cholecystectomy, and one trial did not provide this information. The average age of participants in the trials ranged between 48 years and 63 years in the 10 trials that provided this information. The proportion of females ranged between 55.0% and 79.0% in the 11 trials that provided this information. There was no significant difference between the drain group (1/840) (adjusted proportion: 0.1%) and the 'no drain' group (2/841) (0.2%) (RR 0.41; 95% CI 0.04 to 4.37) in short-term mortality in the ten trials with 1681 participants reporting on this outcome. There was no significant difference between the drain group (7/567) (adjusted proportion: 1.1%) and the 'no drain' group (3/576) (0.5%) in the

  17. THE APPLICATION OF CATIONIC POLYACRYLAMIDE AS DRAINAGE AND RETENTION AIDS

    Institute of Scientific and Technical Information of China (English)

    JinWang; KefuChen; FushanChent; ChuanshanZhao; RendangYang

    2004-01-01

    Cationic polyacrylamide (CPAM) which was prepared through complex initiation system in laboratory and cationic polyacrylamide (Ciba) were used asretention and drainage aids for bleached wheat strawpulp. The influences of (polydiallyldimethlammonium chloride) PDADMAC and PDADMAC/CPAMon Zeta potential and drainability of pulp was investigated. The dual drainage and retention systems suchas CPAM/modified bentonite, CPAM/colloidal SiO2,as well as their comparison between the two systemswere discussed, and the optimal dosages of additiveswere determined. The results showed that: the complex systems can further enhance filler retention,drainability of pulp and strength properties of paper.

  18. Quaternary Reorganization of North American Mid-continent Drainage Systems

    Science.gov (United States)

    Carson, E. C.; Rawling, J. E., III; Attig, J. W.; Bates, B. R.

    2013-12-01

    Identification of ancestral drainage systems in the North American mid-continent has been a topic of research and debate among geologists since the middle of the 19th Century. Over time our understanding of the significance of Quaternary glaciations in reshaping drainage patterns has grown. The ancestral Teays River, which drained large areas of the central Appalachians and flowed westward across Indiana and western Illinois, was dammed multiple times by Quaternary glaciers before finally being rerouted to the course of the modern central Ohio River. Similarly, the northward-flowing ancestral Pittsburgh River was dammed by pre-Illinoian glaciers; subsequent stream piracy converted this river system into the modern Allegheny, Monongahela and uppermost Ohio Rivers. Deposits and geomorphic features along the westward-flowing lower Wisconsin River indicate that the modern upper Mississippi River and Wisconsin River may have experienced a similar history of ice blockage, stream piracy, and radical rerouting. Coring into the Bridgeport strath terrace along the lower Wisconsin River reveals that the bedrock surface dips to the east, indicating the valley was cut by an eastward-flowing river. We believe the most likely scenario following this interpretation is that an ancestral river flowing along the modern upper Mississippi River valley made a sharp bend at Prairie du Chien, WI, and flowed eastward along the valley occupied by the modern lower Wisconsin River. This river, referred to here as the Wyalusing River, likely flowed northeastward into the Great Lakes (St. Lawrence) drainage until that path was blocked by ice advancing from the northwest. Subsequent stream piracy immediately south of the modern confluence of the Mississippi and Wisconsin Rivers rerouted these streams, converting them to the headwaters of the greater Mississippi drainage. The combined rerouting of these river systems into entirely different drainage basins necessitates significant fundamental

  19. Spontaneous drainage in syringomyelia: magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, E.I.; Mendelevich, E.G. [Kazan State Medical Univ. (Russian Federation). Dept. of Neurology and Rehabilitation; Ibatullin, M.M. [Republic Medical Diagnostic Centre of Tatarstan, Kazan (Russian Federation). Department of Radiology

    2000-09-01

    We present five cases of syringomyelia associated with Chiari I or other causes of partial obstructions at the cervicomedullary junction, with spontaneous disruption of the wall of a cervical syrinx and formation of a communication between the cavity and the subarachnoid space, shown on axial MRI. MRI can be used to investigate the hydrodynamics, showing the liquid inside the disrupted syrinx wall and the pathway of drainage. The finding of spontaneous drainage may be important for understanding the pathogenesis of syringomyelia and may be helpful for choosing a surgical approach. (orig.)

  20. Practical considerations in voltage stability assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kundur, P.; Gao, B. [Powertech Labs. Inc., Surrey, BC (Canada)

    1994-12-31

    This paper deals with some of the most important practical issues related to voltage stability assessment of large practical systems. A brief discussion of the practical aspects of voltage stability problem and prevention of voltage instability is given first, followed by descriptions of different analytical techniques and tools for voltage stability analysis. Presentations of analytical tools is focused on the VSTAB program which incorporates the modal analysis, continuation power flow, and shortest distance to instability techniques, Finally, an example case study of a practical large system is presented. The case study illustrates how modal analysis is used to determine the most effective load shedding scheme for preventing voltage instability. (author) 15 refs., 2 figs., 2 tabs.

  1. Radiatively heated high voltage pyroelectric crystal pulser

    Energy Technology Data Exchange (ETDEWEB)

    Antolak, A.J., E-mail: antolak@sandia.gov [Sandia National Laboratories, Livermore, CA 94550 (United States); Chen, A.X. [Sandia National Laboratories, Livermore, CA 94550 (United States); Leung, K.-N. [Sandia National Laboratories, Livermore, CA 94550 (United States); Nuclear Engineering Department, University of California, Berkeley (United States); Morse, D.H.; Raber, T.N. [Sandia National Laboratories, Livermore, CA 94550 (United States)

    2014-01-21

    Thin lithium tantalate pyroelectric crystals in a multi-stage pulser were heated by quartz lamps during their charging phase to generate high voltage pulses. The charging voltage was determined empirically based on the measured breakdown voltage in air and verified by the induced breakdown voltage of an external high voltage power supply. A four-stage pyroelectric crystal device generated pulse discharges of up to 86 kV using both quartz lamps (radiative) and thermoelectric (conductive) heating. Approximately 50 mJ of electrical energy was harvested from the crystals when radiatively heated in air, and up to 720 mJ was produced when the crystals were submerged in a dielectric fluid. It is anticipated that joule-level pulse discharges could be obtained by employing additional stages and optimizing the heating configuration.

  2. Non-contact current and voltage sensor

    Science.gov (United States)

    Carpenter, Gary D; El-Essawy, Wael; Ferreira, Alexandre Peixoto; Keller, Thomas Walter; Rubio, Juan C; Schappert, Michael A

    2014-03-25

    A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.

  3. Coordinated Voltage Control of Active Distribution Network

    Directory of Open Access Journals (Sweden)

    Xie Jiang

    2016-01-01

    Full Text Available This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG. The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB.

  4. Nuclear microprobe investigation of the effects of ionization and displacement damage in vertical, high voltage GaN diodes

    Science.gov (United States)

    Vizkelethy, G.; King, M. P.; Aktas, O.; Kizilyalli, I. C.; Kaplar, R. J.

    2017-08-01

    Radiation responses of high-voltage, vertical gallium-nitride (GaN) diodes were investigated using Sandia National Laboratories' nuclear microprobe. Effects of the ionization and the displacement damage were studied using various ion beams. We found that the devices show avalanche effect for heavy ions operated under bias well below the breakdown voltage. The displacement damage experiments showed a surprising effect for moderate damage: the charge collection efficiency demonstrated an increase instead of a decrease for higher bias voltages.

  5. Axisymmetric Drainage in Hydrophobic Porous Media Micromodels Drainage en géométrie axisymétrique dans des milieux poreux hydrophobes à deux dimensions

    Directory of Open Access Journals (Sweden)

    Cuenca A.

    2013-01-01

    Full Text Available We present studies of axisymmetric drainage in two-dimensional micromodels of porous media using up to date microfabrication and image analysis methods. Drainage of model oil by aqueous solutions is studied at low capillary numbers (Ca typically encountered during oil recovery operations. We use two types of oil-wet micromodels: one is based on a deposition method for creating a random monolayer of micronic glass beads, while the other is made using computer generated random networks etched in glass using wet-lithography. Both models have a central injection scheme and a radial geometry, resulting in a continuous variation of the capillary number during the course of drainage. We first carry out an analysis of experiments at global micromodel scale using computer based image analysis coupled with flow rates and pressure drop measurements. Basic relevant parameters such as permeability, porosity of the micromodel and residual oil in place after waterflooding are extracted. We then take advantage of the ease of observation in transparent micromodels to investigate the drainage phenomenon at local scale. Local saturation and front width are measured as a function of the local capillary number. Interestingly, because of the radial flow geometry, our experiments allow a continuous plotting of the micromodels capillary desaturation curve on several decades. As expected but never precisely observed, all points of various experiments collapse on a single capillary desaturation curve for a given micromodel. However, we observe dissimilar behaviors between the two types of micromodels. We discuss this phenomenon in light of the pore scale geometrical differences between the two models. Nous présentons une étude de phénomènes de drainage dans des micromodèles bidimensionnels de milieu poreux s’appuyant sur des méthodes modernes de microfabrication et d’analyse. Le drainage d’huile par des solutions aqueuses est étudié à de faibles nombres

  6. Hysteresis in voltage-gated channels.

    Science.gov (United States)

    Villalba-Galea, Carlos A

    2016-09-30

    Ion channels constitute a superfamily of membrane proteins found in all living creatures. Their activity allows fast translocation of ions across the plasma membrane down the ion's transmembrane electrochemical gradient, resulting in a difference in electrical potential across the plasma membrane, known as the membrane potential. A group within this superfamily, namely voltage-gated channels, displays activity that is sensitive to the membrane potential. The activity of voltage-gated channels is controlled by the membrane potential, while the membrane potential is changed by these channels' activity. This interplay produces variations in the membrane potential that have evolved into electrical signals in many organisms. These signals are essential for numerous biological processes, including neuronal activity, insulin release, muscle contraction, fertilization and many others. In recent years, the activity of the voltage-gated channels has been observed not to follow a simple relationship with the membrane potential. Instead, it has been shown that the activity of voltage-gated channel displays hysteresis. In fact, a growing number of evidence have demonstrated that the voltage dependence of channel activity is dynamically modulated by activity itself. In spite of the great impact that this property can have on electrical signaling, hysteresis in voltage-gated channels is often overlooked. Addressing this issue, this review provides examples of voltage-gated ion channels displaying hysteretic behavior. Further, this review will discuss how Dynamic Voltage Dependence in voltage-gated channels can have a physiological role in electrical signaling. Furthermore, this review will elaborate on the current thoughts on the mechanism underlying hysteresis in voltage-gated channels.

  7. Measurement and analysis of postsynaptic potentials using a novel voltage-deconvolution method.

    Science.gov (United States)

    Richardson, Magnus J E; Silberberg, Gilad

    2008-02-01

    Accurate measurement of postsynaptic potential amplitudes is a central requirement for the quantification of synaptic strength, dynamics of short-term and long-term plasticity, and vesicle-release statistics. However, the intracellular voltage is a filtered version of the underlying synaptic signal and so a method of accounting for the distortion caused by overlapping postsynaptic potentials must be used. Here a voltage-deconvolution technique is demonstrated that defilters the entire voltage trace to reveal an underlying signal of well-separated synaptic events. These isolated events can be cropped out and reconvolved to yield a set of isolated postsynaptic potentials from which voltage amplitudes may be measured directly-greatly simplifying this common task. The method also has the significant advantage of providing a higher temporal resolution of the dynamics of the underlying synaptic signal. The versatility of the method is demonstrated by a variety of experimental examples, including excitatory and inhibitory connections to neurons with passive membranes and those with activated voltage-gated currents. The deconvolved current-clamp voltage has many features in common with voltage-clamp current measurements. These similarities are analyzed using cable theory and a multicompartment cell reconstruction, as well as direct comparison to voltage-clamp experiments.

  8. Origin of the transition voltage in gold–vacuum–gold atomic junctions

    KAUST Repository

    Wu, Kunlin

    2012-12-13

    The origin and the distance dependence of the transition voltage of gold-vacuum-gold junctions are investigated by employing first-principles quantum transport simulations. Our calculations show that atomic protrusions always exist on the electrode surface of gold-vacuum-gold junctions fabricated using the mechanically controllable break junction (MCBJ) method. The transition voltage of these gold-vacuum-gold junctions with atomically sharp electrodes is determined by the local density of states (LDOS) of the apex gold atom on the electrode surface rather than by the vacuum barrier shape. More specifically, the absolute value of the transition voltage roughly equals the rising edge of the LDOS peak contributed by the 6p atomic orbitals of the gold atoms protruding from the electrode surface, whose local Fermi level is shifted downwards when a bias voltage is applied. Since the LDOS of the apex gold atom depends strongly on the exact shape of the electrode, the transition voltage is sensitive to the variation of the atomic configuration of the junction. For asymmetric junctions, the transition voltage may also change significantly depending on the bias polarity. Considering that the occurrence of the transition voltage requires the electrode distance to be larger than a critical value, the interaction between the two electrodes is actually rather weak. Consequently, the LDOS of the apex gold atom is mainly determined by its local atomic configuration and the transition voltage only depends weakly on the electrode distance as observed in the MCBJ experiments. © 2013 IOP Publishing Ltd.

  9. Simulation Test System of Non-Contact D-dot Voltage Transformer

    Science.gov (United States)

    Yang, Jie; Wang, Jingang; Luo, Ruixi; Gao, Can; Songnong, Li; Kongjun, Zhou

    2016-04-01

    The development trend of future voltage transformer in smart grid is non-contact measurement, miniaturization and intellectualization. This paper proposes one simulation test system of non-contact D-dot transformer for voltage measurement. This simulation test system consists of D-dot transformer, signal processing circuit and ground PC port. D-dot transformer realizes the indirect voltage measurement by measuring the change rate of electric displacement vector, a non-contact means (He et al. 2004, Principles and experiments of voltage transformer based on self-integrating D-dot probe. Proc CSEE 2014;15:2445-51). Specific to the characteristics of D-dot transformer signals, signal processing circuits with strong resistance to interference and distortion-free amplified sensor output signal are designed. WIFI wireless network is used to transmit the voltage detection to LabVIEW-based ground collection port and LabVIEW technology is adopted for signal reception, data processing and analysis and other functions. Finally, a test platform is established to simulate the performance of the whole test system of single-phase voltage transformer. Test results indicate that this voltage transformer has sound real-time performance, high accuracy and fast response speed and the simulation test system is stable and reliable and can be a new prototype of voltage transformers.

  10. Origin of the transition voltage in gold-vacuum-gold atomic junctions.

    Science.gov (United States)

    Wu, Kunlin; Bai, Meilin; Sanvito, Stefano; Hou, Shimin

    2013-01-18

    The origin and the distance dependence of the transition voltage of gold-vacuum-gold junctions are investigated by employing first-principles quantum transport simulations. Our calculations show that atomic protrusions always exist on the electrode surface of gold-vacuum-gold junctions fabricated using the mechanically controllable break junction (MCBJ) method. The transition voltage of these gold-vacuum-gold junctions with atomically sharp electrodes is determined by the local density of states (LDOS) of the apex gold atom on the electrode surface rather than by the vacuum barrier shape. More specifically, the absolute value of the transition voltage roughly equals the rising edge of the LDOS peak contributed by the 6p atomic orbitals of the gold atoms protruding from the electrode surface, whose local Fermi level is shifted downwards when a bias voltage is applied. Since the LDOS of the apex gold atom depends strongly on the exact shape of the electrode, the transition voltage is sensitive to the variation of the atomic configuration of the junction. For asymmetric junctions, the transition voltage may also change significantly depending on the bias polarity. Considering that the occurrence of the transition voltage requires the electrode distance to be larger than a critical value, the interaction between the two electrodes is actually rather weak. Consequently, the LDOS of the apex gold atom is mainly determined by its local atomic configuration and the transition voltage only depends weakly on the electrode distance as observed in the MCBJ experiments.

  11. An ANN Based Capicitor Voltage Balancing Method For Neutral Point Clamped Multi-Level Inverter

    Directory of Open Access Journals (Sweden)

    P.J.S. Praveen,

    2015-11-01

    Full Text Available Multi-level inverters are became popular for usage in medium voltage, low voltage power applications due to flexibility in control and better performance characteristics in terms of harmonic regulation. Neutral point clamped are popular as they require less number of sources as their input when compared with their counter parts i.e. cascaded multi-level inverters and found to be reliable when compared with flying capacitor based multi-level inverters. But when neutral clamped technologies are used for generation of three-phase voltages, the capacitors that are connected at input side experiences imbalance in their voltages, this makes neutral point clamped multi-level inverters less reliable. In the proposed work an attempt is made to study circuits that balances the capacitor voltages and a scheme is investigated for balancing the capacitor voltages. Method proposed in [1] uses PID controller for balancing the capacitor voltages. In this project PI based control scheme and artificial neural network (ANN based control scheme for the front end circuit shown in [1] are designed for achieving balance among the capacitor voltages. The proposed control scheme is simulated with the help of Simpowersystems block set and neural network toolbox of MATLAB software for different load conditions. Results obtained from ANN based controller and PI controller are presented.

  12. Open Drainage and Detention Basin Combined System Optimization

    Directory of Open Access Journals (Sweden)

    M. E. Banihabib

    2017-01-01

    Full Text Available Introduction: Since flooding causes death and economic damages, then it is important and is one of the most complex and destructive natural disaster that endangers human lives and properties compared to any other natural disasters. This natural disaster almost hit most of countries and each country depending on its policy deals with it differently. Uneven intensity and temporal distribution of rainfall in various parts of Iran (which has arid and semiarid climate causes flash floods and leads to too much economic damages. Detention basins can be used as one of the measures of flood control and it detains, delays and postpones the flood flow. It controls floods and affects the flood directly and rapidly by temporarily storing of water. If the land topography allows the possibility of making detention basin with an appropriate volume and quarries are near to the projects for construction of detention dam, it can be used, because of its faster effect comparing to the other watershed management measures. The open drains can be used alone or in combination with detention basin instead of detention basin solitarily. Since in the combined system of open and detention basin the dam height is increasing in contrast with increasing the open drainage capacity, optimization of the system is essential. Hence, the investigation of the sensitivity of optimized combined system (open drainage and detention basin to the effective factors is also useful in appropriately design of the combined system. Materials and Methods: This research aims to develop optimization model for a combined system of open drainage and detention basins in a mountainous area and analyze the sensitivity of optimized dimensions to the hydrological factors. To select the dam sites for detention basins, watershed map with scale of 1: 25000 is used. In AutoCAD environment, the location of the dam sites are assessed to find the proper site which contains enough storage volume of the detention

  13. THE STUDY OF IMPROVING OF STABILITY AND RELIABILITY FOR 250kV HIGH VOLTAGE POWER%改进250kV高压电源稳定性与可靠性的研究

    Institute of Scientific and Technical Information of China (English)

    廖小东; 郑思孝; 刘仲阳; 孙官清; 王培录

    2001-01-01

    The hitches for a ppearing in the high voltage power at 250kV and improvement of the controlling circuit techniques are described. The static high voltage output was exercised by raising the high voltage gradually. The affects between the current load-variety and the vaviety of the input voltoge at + 1096 against the high voltage stability have been obtained. The experiments prove that the high voltage stability have been raised greatly via improving the controlling circuit.

  14. EFFECTIVENESS OF AUTOGENIC DRAINAGE VERSUS POSTURAL DRAINAGE ON OXYGEN SATURATION IN PATIENTS WITH CHRONIC BRONCHITIS WITH 15 MINUTES POST THERAPY

    Directory of Open Access Journals (Sweden)

    V. Kiran

    2014-12-01

    Full Text Available Background: Patients with COPD will have more amount of secretions. To clear the secretions by using of different bronchial hygiene techniques like postural drainage and autogenic drainage technique, manual hyperventilation technique ,active cycle breathing technique .Hence in this study to compare the short-term effects of postural drainage with clapping (PD and autogenic drainage (AD on level of oxygen saturation in blood, and amount of sputum recovery. Methodology: The study was done on 60 patients with COPD. Dividing Patients into two group and patients were treated with PD or AD in separate Groups. The effectiveness of the treatment was measured up to 6 days. Pulse oximetry was monitored and sputum was collected immediately after treatment and 15 minutes following each treatment. Results: The results of the study shown that there was significant difference in the amount of sputum recovered with AD (14.0±3.5 g vs PD (24.4±3.0 g and significant differences in Oxygen saturation; during PD fell from 93.3±0.7% to 91.2±0.8% (p<0.01 and required 15 min following treatment to return to baseline. Oxygen saturation did not fall during AD and increased to gradually following complete treatment days (baseline, 93.3±0.8%; p<0.01. Conclusion: Hence this study concludes that Autogenic drainage is more effective in improving spo2 in COPD & does not cause a sudden fall in spo2 as occurs in Postural drainage immediately after therapy. And it can be better tolerated by patients with COPD while producing fewer benefits in sputum clearance. In concern to mean amount of secretion removal Postural is found to be more effective

  15. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Marzocchi, Badder

    2017-01-01

    The CMS Electromagnetic Calorimeter is made of scintillating lead tungstate crystals, using avalanche photodiodes (APD) as photo-detectors in the barrel part. The high voltage system, consisting of 1224 channels, biases groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  16. Voltage-controlled accommodating IOL system using an ion polymer metal composite actuator.

    Science.gov (United States)

    Horiuchi, Tetsuya; Mihashi, Toshifumi; Fujikado, Takashi; Oshika, Tetsuro; Asaka, Kinji

    2016-10-03

    Surgeons treat cataracts by replacing the clouded lens with an intraocular lens (IOL), but patients are required to wear reading glasses for tasks requiring near vision. We suggest a new voltage-controlled accommodating IOL made of an ionic polymer metal composite (IPMC) actuator to change focus. An in vitro experiment was conducted where an actuator was placed inside the eye and moved with applied voltage. The lens attached to the actuator was deformed by its movement to change the patient's focus. The results showed that this system can accommodate a change of approximately 0.8 diopters under an applied voltage of ± 1.3 V.

  17. Antiferromagentic resonance detected by direct current voltages in MnF{sub 2}/Pt bilayers

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Philipp, E-mail: philipp.ross.13@ucl.ac.uk [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Schreier, Michael, E-mail: michael.schreier@wmi.badw.de; Lotze, Johannes [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, Technische Universität München, Garching (Germany); Huebl, Hans; Goennenwein, Sebastian T. B. [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Nanosystems Initiative Munich, Munich (Germany); Gross, Rudolf [Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, Technische Universität München, Garching (Germany); Nanosystems Initiative Munich, Munich (Germany)

    2015-12-21

    We performed coplanar waveguide-based broadband ferromagnetic resonance experiments on the antiferromagnetic insulator MnF{sub 2}, while simultaneously recording the DC voltage arising in a thin platinum film deposited onto the MnF{sub 2}. The antiferromagnetic resonance is clearly reflected in both the transmission through the waveguide as well as the DC voltage in the Pt strip. The DC voltage remains largely unaffected by field reversal and thus presumably stems from microwave rectification and/or heating effects. However, we identify a small magnetic field orientation dependent contribution, compatible with antiferromagnetic spin pumping theory.

  18. High Voltage Bidirectional Flyback Converter Driving DEAP Actuator for Automotive Applications

    DEFF Research Database (Denmark)

    Huang, Lina; Zhang, Zhe; Andersen, Michael A. E.;

    2013-01-01

    DEAP (Dielectric Electro Active Polymer) is a new type of smart material. The actuator based on DEAP material tends to be applied in a variety of occasions. It will have prosperous future when employed in automotive field. This paper is focused on the design and implementation of a low input volt...... voltage and high output voltage bidirectional converter for driving the DEAP actuator. The detailed design and implemented parameters have been summarized, especially for the high voltage transformer. The experiments have been performed to validate the design and implementation....

  19. Investigating the impact of Lake Agassiz drainage routes on the 8.2 ka cold event with climate modeling

    Directory of Open Access Journals (Sweden)

    Y.-X. Li

    2009-03-01

    Full Text Available The 8.2 ka event is the most prominent abrupt climate change in the Holocene and is widely believed to result from catastrophic drainage of proglacial lakes Agassiz and Ojibway (LAO that routed through the Hudson Bay and the Labrador Sea into the North Atlantic Ocean, and perturbed Atlantic meridional overturning circulation (MOC. One key assumption of this triggering mechanism is that the LAO freshwater drainage was spread over the Labrador Sea. Recent data, however, show no evidence of lowered δ18O values from the open Labrador Sea around 8.2 ka. Instead, negative δ18O anomalies are found close to the east coast of North America, extending as far south as Cape Hatteras, North Carolina, suggesting that the freshwater drainage was probably confined to a long stretch of continental shelf before fully mixing with North Atlantic Ocean water. Here we conduct a sensitivity study that examines the effects of this southerly drainage route on the 8.2 ka event with the ECBilt-CLIO-VECODE model. Hosing experiments of four different routing scenarios, where freshwater was introduced to the Labrador Sea in the northerly route (R1 and to three different locations (Grand Banks – R2, George Bank – R3, and Cape Hatteras – R4 on the southerly route, were performed with 0.45 m sea-level equivalent (SLE, 0.90 m SLE, and 1.35 m SLE of freshwater introduced over 5 years to investigate the routing effects on model responses. The modelling results show that a southerly drainage route is plausible but generally yields reduced climatic consequences in comparison to those of a northerly route. This finding implies that more freshwater would be required for a southerly route than for a northerly route to produce the same climate anomaly.

  20. New Control Technique Applied in Dynamic Voltage Restorer for Voltage Sag Mitigation

    Directory of Open Access Journals (Sweden)

    Rosli Omar

    2010-01-01

    Full Text Available The Dynamic Voltage Restorer (DVR was a power electronics device that was able to compensate voltage sags on critical loads dynamically. The DVR consists of VSC, injection transformers, passive filters and energy storage (lead acid battery. By injecting an appropriate voltage, the DVR restores a voltage waveform and ensures constant load voltage. There were so many types of the control techniques being used in DVR for mitigating voltage sags. The efficiency of the DVR depends on the efficiency of the control technique involved in switching the inverter. Problem statement: Simulation and experimental investigation toward new algorithms development based on SVPWM. Understanding the nature of DVR and performance comparisons between the various controller technologies available. The proposed controller using space vector modulation techniques obtain higher amplitude modulation indexes if compared with conventional SPWM techniques. Moreover, space vector modulation techniques can be easily implemented using digital processors. Space vector PWM can produce about 15% higher output voltage than standard Sinusoidal PWM. Approach: The purpose of this research was to study the implementation of SVPWM in DVR. The proposed control algorithm was investigated through computer simulation by using PSCAD/EMTDC software. Results: From simulation and experimental results showed the effectiveness and efficiency of the proposed controller based on SVPWM in mitigating voltage sags in low voltage distribution systems. It was concluded that its controller also works well both in balance and unbalance conditions of voltages. Conclusion/Recommendations: The simulation and experimental results of a DVR using PSCAD/EMTDC software based on SVPWM technique showed clearly the performance of the DVR in mitigating voltage sags. The DVR operates without any difficulties to inject the appropriate voltage component to correct rapidly any anomaly in the supply voltage to keep the