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Sample records for based primary pumping

  1. Primary pump suction pressure limits

    International Nuclear Information System (INIS)

    In conjunction with the operational testing program which was carried out prior to the startup of N Reactor, a study was carried out to establish limits for suction pressure of the primary (reactor coolant) pumps. The purpose of the report is to document the results of the study and interpret them with respect to the current mode of reactor operation

  2. Assertion based verification methodology for HDL designs of primary sodium pump speed and eddy current flow measurement systems of PFBR

    International Nuclear Information System (INIS)

    With the growing complexity and size of digital designs, functional verification has become a huge challenge. The validation and testing process accounts for a significant percentage of the overall development effort and cost for electronic systems. Many studies have shown that up to 70% of the design development time and resources are spent on functional verification. Functional errors manifest themselves very early in the design flow, and unless they are detected upfront, they can result in severe consequences - both financially and from a safety viewpoint. This paper covers the various types of verification methodologies and focuses on Assertion Based Verification Methodology for HDL designs, taking as case studies, the Primary Sodium Pump Speed and Eddy Current Flow Measurement Systems of PFBR. (author)

  3. Impedance calculations for power cables to primary coolant pump motors

    International Nuclear Information System (INIS)

    The LOFT primary system motor generator sets are located in Room B-239 and are connected to the primary coolant pumps by means of a power cable. The calculated average impedance of this cable is 0.005323 ohms per unit resistance and 0.006025 ohms per unit reactance based on 369.6 kVA and 480 volts. The report was written to show the development of power cable parameters that are to be used in the SICLOPS (Simulation of LOFT Reactor Coolant Loop Pumping System) digital computer program as written in LTR 1142-16 and also used in the pump coastdowns for the FSAR Analysis

  4. Vibration analysis of primary air pump JE01 AP003

    International Nuclear Information System (INIS)

    JE01 AP003 primary coolant pump is one of the main components in the safe operation of the reactor so that needs to be done early detection of damage types and levels of its constituent components. The main components of the pump that is often damaged bearing. The purpose of this paper is to know the symptoms of bearing damage and the level of damage based on vibration analysis. One indication of the bearing has been damaged, that is the vibration or temperature rise in the bearing. One way to detect early symptoms of damage to the pump is to use the vibration response peak Based on the analysis of the measurement results cited the obtained results that the primary coolant pump JE01 AP003 has been damage to a free end looseness bearing with moderate levels of damage. Need JE01 AP003 bearing replacement even though the damage is not severe. (author)

  5. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  6. Primary pump vibration under accident conditions

    International Nuclear Information System (INIS)

    This report presents the results of an international survey on the subject of vibration in nuclear primary coolant pumps due to two-phase flow, accident conditions. The literature search also revealed few Canadian references other than those of Ontario Hydro. Ontario Hydro's work has been extensive. Confidence in the mechanical integrity of the pumpsets is good, given the extent of the testing. However, conclusions with respect to piping integrity and thermal-hydraulic performance are difficult to determine due to the inexact geometry of the piping and the difficulties in estimating fluid conditions at the pump. The tests help to understand the phenomena and provide background information for analysis, but should be applied with caution to plant analyses. Much of the discussion in the report relates to pump head instability. This is perceived to be the most important flow regime causing vibration, as attested by the emphasis of the reviewed literature. A method for quantitative assessment of the forcing functions acting on the pump-piping system due to void generation and collapse is recommended. A relatively fundamental analytical approach is proposed, supplemented by reduced scale testing in the latter stages. 151 refs

  7. A reliability-centered maintenance program for primary reactor pumps

    International Nuclear Information System (INIS)

    Reactor coolant and recirculation pumps require significant outage times to repair and, as a consequence, are a major contributor to plant downtime and lost capacity. To improve reliability of these primary reactor pumps, a comprehensive preventative maintenance program has been developed using the principles of reliability-centered maintenance. This method establishes the frequency of past failures, estimates the probability of future occurrences, and assesses the effect of all potential functional failures of the pump. Maintenance tasks are then defined to address those specific failure modes that have the largest probability of occurrence and the greatest impact on plant availability. Benefits include: improved reliability, a maintenance program that satisfies the industry initiative on maintenance, prudence documentation in support of unforeseen outages, and documented justification for rate-base increases for maintenance costs

  8. Development of ANC-type empirical two-phase pump model for full size CANDU primary heat transport pump

    International Nuclear Information System (INIS)

    The development of an ANC-type empirical two-phase pump model for CANDU (Canadian Deuterium) reactor primary heat transport pumps is described in the present paper. The model was developed based on Ontario Hydro Technologies' full scale Darlington pump first quadrant test data. The functional form of the ANC model which is widely used was chosen to facilitate the implementation of the model into existing computer codes. The work is part of a bigger test program with the aims: (1) to produce high quality pump performance data under off-normal operating conditions using both full-size and model scale pumps; (2) to advance our basic understanding of the dominant mechanisms affecting pump performance based on more detailed local measurements; and (3) to develop a 'best-estimate' or improved pump model for use in reactor licensing and safety analyses. (author)

  9. Upgrading primary heat transport pump seals

    International Nuclear Information System (INIS)

    Changes in the operating environment at the Bruce-A Nuclear Generating Station created the need for an upgraded Primary Heat Transport Pump (PHTP) seal. In particular, the requirement for low pressure running during more frequent start-ups exposed a weakness of the CAN2 seal and reduced its reliability. The primary concern at Bruce-A was the rotation of the CAN2 No. 2 stators in their holders. The introduction of low pressure running exacerbated this problem, giving rapid wear of the stator back face, overheating, and thermocracking. In addition, the resulting increase in friction between the stator and its holder increased stationary-side hysteresis and thereby changed the seal characteristic to the point where interseal pressure oscillations became prevalent. The resultant increased hysteresis also led to hard rubbing of the seal faces during temperature transients. An upgraded seal was required for improved reliability to avoid forced outages and to reduce maintenance costs. This paper describes this upgraded 'replacement seal' and its performance history. In spite of the 'teething' problems detailed in this paper, there have been no forced outages due to the replacement seal, and in the words of a seal maintenance worker at Bruce-A, 'it allows me to go home and sleep at night instead of worrying about seal failures.' (author)

  10. Design Of Pump Monitoring Of Primary Cooling System

    International Nuclear Information System (INIS)

    Monitoring of 3 primary cooling pumps done visually by operator on the spot. The operator must be check oil in a sight glass, oil leakage during pump operation and water leakage. If reaktor power increase about more than 3 MW, the radiation exposure also increase in the primary cell and that's way the operator can not check the pumps. To continuing monitor all pump without delay, one system has been added I.e Closed Circuit Television (CCTV). This system using 3 video camera to monitor 3 pumps and connected to one receiver video monitor by coaxial cable located in Main Control Room. The sequence monitoring can be done by sequential switcher

  11. Point Lepreau primary heat transport pump wear ring cracking

    International Nuclear Information System (INIS)

    The number 3 Primary Heat Transport (PHT) pump from Point Lepreau Nuclear Generating Station (Point Lepreau) was disassembled after more than 30 years of service for inspection during station refurbishment. The disassembly and inspection were performed to provide assurance of continued satisfactory operation during life extension. The inspection revealed cracks in the wear ring, at and near the tack welds (Type 309 stainless steel weld metal) at the cap screws that attach the Type 420 stainless steel wear ring to the body of the pump. Investigative work consisted of on-site PT and replication of the microstructure at the surface of the wear ring, subsequent impressions of two crack faces, and hardness determinations. This paper describes the investigative work and conclusions associated with resolution of the following questions: 1. What is the most likely cause of the cracking? 2. Will the cracks propagate within the base metal of the wear ring? 3. If propagation is possible, what is the risk of cracks intersecting, such that a piece of metal could become dislodged? Question number 3 has clear ramifications with respect to foreign material entering and damaging a nuclear fuel-containing pressure tube. There are also questions associated with extent of condition, specifically, whether other PHT pumps may have similar or worse cracking and whether such cracks will grow. Results will be applied to wear rings in other PHT pumps at Point Lepreau and are likely to be applicable to similar components in other CANDU PHT pumps. (author)

  12. Examination and replacement of electromagnetic pumps from FFTF primary circuits

    International Nuclear Information System (INIS)

    On November 16, 1984, a leak was discovered in the Fast Flux Test Facility (FFTF) primary sodium sampling system. The leak occurred in one of two parallel electromagnetic (EM) pumps designed to take suction from the primary system drain tank and pump sodium through the cold trap to maintain coolant purity. The purpose of this paper is to describe the examination of the pump after its removal from the circuit, define the apparent cause of the leak, and give the applications of the examination to future plant operations

  13. Study on the decontamination of primary cooling pump in Hanaro

    International Nuclear Information System (INIS)

    The HANARO, a multi-purpose research reactor of 30 MWth open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. Recently, ten years after the initial operation of the HANARO, one of the two primary cooling pumps was decontaminated for overhaul maintenance in 2004. Before decontamination exposure doserate and surface contamination level of primary cooling pump measured at 4 points. After final decontamination exposure doserate and surface contamination level of primary cooling pump remeasured by same method done before. It is easy to decontaminate the out side exposed surfaces of the pump, but it is difficult to approach the inside surface due to double volute installed in the casing. Therefore, a new decontamination facility has been developed to solve this problem. A concentrated de-contaminant (DX-300) is rotated in the closed pump casing by the impeller actuated by a temporary motor. Nuclide particles are removed by the emulsification effect of the de-contaminant and the surface contaminants are chemically removed from the pump by the corrosion and dissolution effect. The inside surfaces of the primary cooling pump have been decontaminated by using the facility. As results, the contamination level of the inside surfaces was maintained below the surface contamination limit

  14. Effect of hydrogen combustion in the primary pump compartment

    International Nuclear Information System (INIS)

    Hydrogen combustion in a nuclear power plant may threaten the integrity of some important systems and components. In this paper, the effect of hydrogen combustion in the primary pump compartment is analyzed by different initial hydrogen concentration and igniter locations using Computational Fluid Dynamics method. The results show that the combustion is confined to a limited area without pump damage at about 6.6% hydrogen volume fraction. Once igniting the hydrogen, the combustion affects the whole compartment at the 12% hydrogen volume fraction. The stress caused by the great temperature gradient or high temperature may damage the primary pump. Igniters at the lower location accelerate the combustion process and cause a threat to the pump integrity. (authors)

  15. Fast Flux Test Facility replacement of a primary sodium pump

    International Nuclear Information System (INIS)

    The Fast Flux Test Facility is a 400 MW Thermal Sodium Cooled Fast Reactor operated by Westinghouse Hanford Company for the US Department of Energy. During startup testing in 1979, the sodium level in one of the primary sodium pumps was inadvertently raised above the normal height. This resulted in distortion of the pump shaft. Pump replacement was carried out using special maintenance equipment. Nuclear radiation and contamination were not significant problems since replacement operations were carried out shortly after startup of the Fast Flux Test Facility

  16. Selection of an optimized control nuclide to halt primary pumps

    International Nuclear Information System (INIS)

    Primary pumps are indispensable equipment to a nuclear power station. Besides maintaining the safe operation a unit, they play an un-replaceable function to control radiation source term. Selecting an optimized radionuclide to control the halt of primary pumps is an essential guide to deal with the problem between outage duration and reduction of radiation source term to a Pressurized Water Reactor (PWR) unit. From operational experiences of Daya Bay Nuclear Power Station (NPS), the author points out that 110mAg is the key nuclide which contributes largely to the radiation on the reactor unload/reload pool surface. The author also recommends a limit of 110mAg for halt of the primary pumps

  17. Analysis of reactor coolant pump transient performance in primary coolant system during start-up period

    International Nuclear Information System (INIS)

    Highlights: ► Relationships between pump heads and the parameters of a system are established. ► Relationships between pump torques and the parameters of a system are established. ► The variables are non-dimensionlized in order to design a new system and pump. ► All variables are solved analytically. Pump characteristics are not required. ► Mechanism of reactor coolant pump start-up is mathematically solved and clarified. - Abstract: The reactor coolant pump is “the heart” of a nuclear reactor and the only high-speed revolving equipment in a pressurized water reactor primary cooling loop system. The accurate prediction of flow and pump transient performance, during start-up transients, is a very important factor in the reactor coolant pumps design and the nuclear reactor design. Based on the momentum conservation equation of the primary coolant and the moment balance relation of the reactor coolant pump, the transient pump total head, the acceleration head and the overcoming friction head during a pump start up are derived. The relationship between the above heads and the parameters of the system fluid and pump is established too. Furthermore, the transient torques during a pump start-up are also derived. They include the torques required to accelerate the coolant fluid, to accelerate the pump rotating parts and to overcome friction of coolant fluid in the pipes system. The relation between the above three transient torques and the parameters of the coolant fluid and the pump is respectively established. In addition, the above variables are all non-dimensionlized in order to design a new system. The transient flow rate and pump speed are solved analytically. The detailed information of the centrifugal pump characteristics is not required. The analytical non-dimensional flow rate, the pump speed, heads and torques are all affected by an energy ratio β. The effects of β on the three transient heads and the three transient torques are discussed

  18. Primary circulating pump trip transient analysis for 500 MWe PHWR

    International Nuclear Information System (INIS)

    The 500 MWe Indian pressurised heavy water (PHWR) incorporates many new features as compared to the earlier 220 MWe PHWRs. To evaluate the new design features like primary heat transport (PHT) system configuration with two loops, four primary circulating pumps (PCPs) and four passes through core, addition of a pressuriser (surge tank) in the PHT system along with feed/bleed system and their safety related implications, simulation model development and transient analysis studies are necessary. The paper deals with the details of the mathematical model for PHT system and parametric study on one PCP trip transient analysis with set/step back. The studies were carried out after including the proposed new SGPC program similar to 220 MWe PHWR, which gives a 48 kg/cm2 maximum SG pressure setpoint at zero power, without changing the 100% power set pressure

  19. Analysis on vibration characteristics of the primary sodium pump of China experimental fast reactor

    International Nuclear Information System (INIS)

    The article introduces the rotational model analysis and the vibration test of the primary sodium pump of China Experimental Fast Reactor. Through the establishment of the rotation of the shaft system model, the critical speed has been analyzed. Combined with the pump bearings and motor bearings at double amplitude and RMS vibration velocity measurement experiment, the results show that the vibration characteristics of the primary sodium pump meet the requirements of the operational limits. (author)

  20. Design and evaluation of a primary/secondary pumping system for a heat pump assisted solar thermal loop

    Science.gov (United States)

    Krockenberger, Kyle G.

    A heat pump assisted solar thermal system was designed, commissioned, tested and analyzed over a period of two years. The unique system uses solar energy whenever it is available, but switches to heat pump mode at night or whenever there is a lack of solar energy. The solar thermal energy is added by a variety of flat plat solar collectors and an evacuated tube heat pipe solar collector. The working medium in the entire system is a 50% mixture of propylene glycol and water for freeze protection. During the design and evaluation the primary / secondary pumping system was the focus of the evaluation. Testing within this research focused on the operation modes, pump stability, and system efficiency. It was found that the system was in full operation, the pumps were stable and that the efficiency factor of the system was 1.95.

  1. The Failure Effect of Primary Coolant Pump to Thermo-Hydraulic Characteristic of TRIGA 2000 Reactor

    International Nuclear Information System (INIS)

    Has been done analysis of transient, when TRIGA 2000 reactor loss of primary coolant flow because primary pump loss of electric power, so fail in function.The calculation using RELAP5/MOD32 computer code with reactor core is modeled in the form of different seven channels as representation of different seven areas in core with 116 fuels. This reactor model also considers position of tip of primary pipe of input tank which is below of core, form of lower part core geometry influencing direction and coolant flow rate into core, and existence of diffuser system. The result of calculation in condition of steady state is obtained initiation condition of steady state is reached after 2500 seconds from reactor starts operation on 2000 kW power. On steady state, the channel-3 cladding temperature (hottest) is 149.63℃, the coolant temperature outlet from the channel-3 (hottest) is 105.66℃ , reactor inlet temperature is 32.2℃, and reactor outlet temperature is 46.79℃. The primary coolant entering reactor with flow rate 59.64 kg/s, distributed to core 31.44 kg/s and to by-pass of core or by-pass of chimney 28.20 kg/s. The result of calculation transient is obtained, before scram occur the channel-3 cladding temperature (hottest) is 161.03℃ and the coolant temperature outlet from the channel-3 (hottest) is 117.66℃. In the reactor core is a natural circulation as well (from reactor core, to chimney, to by-pass of chimney, to by-pass of core and back to platform) which is cooling reactor core. Scram occur on 250 seconds after failure of the primary pump. Based on result of this study is known that, when transient condition is happened because primary pump failure, reactor is predicted to stays in safety margin. (author)

  2. Analysis of data obtained in two-phase flow tests of primary heat transport pumps

    International Nuclear Information System (INIS)

    This report analyzes data obtained in two-phase flow tests of primary heat transport pumps performed during the period 1980-1983. Phenomena which have been known to cause pump-induced flow oscillations in pressurized piping systems under two-phase conditions are reviewed and the data analyzed to determine whether any of the identified phenomena could have been responsible for the instabilities observed in those tests. Tentative explanations for the most severe instabilities are given based on those analyses. It is shown that suction pipe geometry probably plays an important role in promoting instabilities, so additional experiments to investigate the effect of suction pipe geometry on the stability of flow in a closed pipe loop under two-phase conditions are recommended

  3. Experience on vibration analysis of primary coolant pumps in Cirus

    International Nuclear Information System (INIS)

    Full text: 40 MW (thermal) CIRUS research reactor has been in operation for over four decades. During the major portion of its life almost all the major mechanical equipment operated continuously in a healthy condition. Since 1988 ageing related breakdown has been noticed in some of the critical components, PCW pumps being one of them. Vibration measurement and analysis is carried out on a routine basis as a part of conditioning monitoring programme. Ageing degradation of various components of the pump has been detected by such a performance monitoring programme. Conditioning monitoring has been found to be quite useful for scheduling of maintenance work on pumps

  4. Primary coolant pump measurement for ICC trend analysis

    International Nuclear Information System (INIS)

    Reactor coolant pump motor power and temperature measurements are used by Babcock and Wilcox (BandW) plant owners to calculate void fraction for trending ICC conditions while the pumps are running. This new measurement technology satisfies NUREG 0737, Item II.F.2, ''. . . licensees shall provide . . . additional instrumentation . . . to supplement existing instrumentation in order to provide a unambiguous, easy-to-interpret indication of inadequate core cooling.'' System accuracy, capability, and limitations are compared to measurement requirements using small break test data and full scale plant analytical studies. Small break experimental data shows that ICC void fraction calculations are conservative compared to gamma densitometer void fraction measurements in the pipe just upstream of the pumps and liquid level conductivity probes in the reactor vessel. Analytical studies verify that a measure of void fraction at the pumps is conservative relative to the desired coolant inventory trend conditions in the reactor vessel

  5. Primary coolant pump measurement for ICC trend analysis

    International Nuclear Information System (INIS)

    Reactor coolant pump motor power and temperature measurements are used by Babcock and Wilcock (B and W) plant owners to calculate void fraction for trending ICC conditions while the pumps are running. This new measurement technology satisfies NUREG 0737, Item II.F.2, ''...licensees shall provide...additional instrumentation...to supplement existing instrumentation in order to provide a unambiguous, easy-to-interpret indication of inadequate core cooling. System accuracy, capability, and limitations are compared to measurement requirements using small break test data and full scale plant analytical studies. Small break experimental data shows that ICC void fraction calculations are conservative compared to gamma densitometer void fraction measurements in the pipe just upstream of the pumps and liquid level conductivity probes in the reactor vessel. Analytical studies verify that a measure of void fraction at the pumps is conservative relative to the desired coolant inventory trend conditions in the reactor vessel

  6. Transient performance during stopping the research reactor primary loop pump

    Energy Technology Data Exchange (ETDEWEB)

    Akbarian Shourkaei, Hossein [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of). Plasma Physics Research Group

    2015-03-15

    In this work an attempt is made to achieve characteristics curves for the Tehran Research Reactor (TRR) during stopping. The TRR pump speed during the event is time dependent. This is done for the TRR first quadrant operating characteristics. The obtained results indicate that the time needed for the coolant flow rate to reach zero is greater than the time necessary for the pump to come to complete stoppage.

  7. Comparison of two arthroscopic pump systems based on image quality

    OpenAIRE

    Tuijthof, G. J. M.; van den Boomen, H.; van Heerwaarden, R. J.; Dijk, C. N. Van

    2008-01-01

    The effectiveness of arthroscopic pump systems has been investigated with either subjective measures or measures that were unrelated to the image quality. The goal of this study is to determine the performance of an automated pump in comparison to a gravity pump based on objective assessment of the quality of the arthroscopic view. Ten arthroscopic operations performed with a gravity pump and ten performed with an automated pump (FMS Duo system) were matched on duration of the surgery and sha...

  8. Cavitation characterization by the acoustic method. Application to a pump model and to the primary pump of the Super Phenix fast reactor

    International Nuclear Information System (INIS)

    In order to study the pumps of fast reactors, water tests were first carried out on a model and then on the primary pumps of Super Phenix. The aim of these tests is to define cavitation acoustic criteria. The results obtained show that noise in a pump varies with the drop in characteristics and can therefore represent a state of cavitation

  9. Startup experiment of a PIUS-type reactor from isothermal fluid condition by feedback control of primary pump

    International Nuclear Information System (INIS)

    A feedback control system of primary pump is proposed for a PIUS-type reactor based on the temperature distribution in the lower density lock. This control system maintains the fluid temperature at the axial center of the lower density lock at the average of the fluid temperatures below and above the lower density lock in order to prevent the poison water from penetrating into the core during normal operation. The effectiveness of this control system was examined in a series of startup tests under different conditions. It has been confirmed from the test results that the control system is quite effective to start up the reactor from a very small fluid temperature difference between the primary loop side and the borated water pool side and even from an isothermal condition by using a preheater installed at the exit of the primary pump. (author)

  10. The examination and replacement of electromagnetic pump from FFTF primary circuit

    International Nuclear Information System (INIS)

    On November 16, 1984 a leak was discovered in the Fast Flux Test Facility (FFTF) Primary Sodium Sampling System electromagnetic pump. The leak was discovered in the course of routine cell entry to investigate the shorted trace heat element. The purpose of this paper is to describe the circumstances surrounding the occurrence of the leak, the processes involved in producing the leak and efforts taken to minimize their effects on future operation of electromagnetic pumps at FFTF. In addition, the replacement of the pump and recovery of the plant also are described. The relative ease of recovery from this incident is indicative of the overall feasibility of the LMR concept

  11. Properties of Graphene Based Parametric Pump

    Institute of Scientific and Technical Information of China (English)

    LUO Song-Lin; WEI Ya-Dong

    2009-01-01

    The adiabatic parametric electron pump of the infinite zigzag graphene ribbons and the infinite armchair graphene ribbons is investigated by the tight binding method. The pumping signals are added by two gates around the ribbons. It is shown that the dc current can be pumped out by cyclically varying the two gate voltages and the pumped current strongly depends on the driving frequency, the pumping amplitude and the phase difference of the gate voltages. The pumped current is mediated by the graphene energy levels and its peaks occur around the energies where transmission coefficients and density of states are large. The pump current may give one peak or two opposite peaks corresponding to each transmission peak or transmission pair peaks. The height and width of the current peaks increase with the amplitude of the pumping driving voltages. The pumped current is antisymmetric about the phase difference φ=π and for small pumping amplitude the pumped current is a sinusoidal function of the phase difference. Some graphene ribbons, although with different widths, have very similar contours of the transmission coefficients and give the same pumped current figures.

  12. Vibration analysis of cooling system of upgraded PARR-1 (primary pumps)

    Energy Technology Data Exchange (ETDEWEB)

    Ayazuddin, S.K.; Baig, R.; Pervez, S.

    1992-12-01

    During the conversion and upgradation of PARR-1, major changes were made in the cooling system of the reactor. These changes involved installation of a new primary pump-motor system, addition of new heat exchanger assemblies and cooling tower. It was therefore planned to perform vibration analysis on the cooling system to check proper installation and investigate any abnormality in the operation. As a first step, vibration measurements were made on the primary pumps PW-P1 and PW-P2.

  13. Countermeasure against thermal fatigue crack of primary loop recirculation pump in BWR

    International Nuclear Information System (INIS)

    The reactor water was fed to the purge water of the mechanical seal on the original design of the primary loop recirculation pump. Because the mechanical seal had a short life due to the cruds in the reactor water, the clean purge water was adopted instead of the reactor water. After this modification, the shallow cracks were found on the surface of the pump shaft and casing cover due to the temperature fluctuation between the cold purge water and the hot pump discharge water. The fundamental mechanism and countermeasure were investigated by scale test, mock-up test and so on. The flow barrier with a heater was contrived through these tests. It has been introduced gradually in operating and constructing PLR pumps after its completion in 1995. The PLR pumps are overhauled around every 10 years in Japan. The first overhaul of the PLR pumps showed no cracks around the pump shaft and casing over after 10 years' operation. This paper presents both its development process and inspection results. (author)

  14. MK-III function tests in JOYO. Primary main cooling pump

    International Nuclear Information System (INIS)

    MK-III function test (SKS-1) that was carried out from October 17, 2001 through October 23, 2001 using MK-III transition core configuration and MK-III function tests (SKS-2) was carried out from January 27, 2003 through February 13, 2003 using MK-III core configuration. The major function tests results of primary cooling system were shown as follows; (1) The stability of the primary main pump flow control system was confirmed on both CAS (cascade) mode and Man (manual) mode. Also no divergence of flow and revolution of the pump were observed at step flow change disturbance. (2) The main motor was shifted to run-back flow control operation in about 54 seconds after scram. The flow rate and pump revolution at run-back operation of A and B cooling system were 167 m3/h and 117 rpm, 185m3/h and 118 rpm respectively. The pump revolution was within the design target revolution 122 rpm ± 8 rpm and the flow was over the 10% of the rated flow. (3) The pony motor was engaged in operation in about 39 seconds after the primary main pump trip. The flow rate and pump revolution at the pony motor operation of A and B cooling system were 180 m3/h and 124 rpm, 190 m3/h and 123 rpm respectively. These values were satisfied the design low limit of 93 rpm and 10% of the rated flow. (4) Free flow coast down time constant was longer than 10 seconds that was design shortest time at both the primary pump trip and run-back operation. (5) Pump over flow column sodium levels of both A and B cooling system at rated operating condition were NL-1550 mm and, NL-1468 mm respectively and were lower than NL-1581 mm of the design value. This result shows the new IHX pressure loss estimation was conservative. (6) It was confirmed that the primary main pump could operate with out scram for up to 0.6 seconds of external power supply loss. (author)

  15. Linear peristaltic pump based on electromagnetic actuators

    Directory of Open Access Journals (Sweden)

    Maddoui Lotfi

    2014-01-01

    Full Text Available In this paper a study and design of a linear peristaltic pump are presented. A set of electromagnetic (solenoid actuators is used as the active tools to drag the liquid by crushing an elastic tube. The pump consists of six serially-connected electromagnetic actuators controlled via an electronic board. This may be considered as a simulated peristalsis action of intestines. The dynamic performances of the pump are investigated analytically and experimentally.

  16. Thermal-hydraulic analysis of tajoura research reactor during primary loop pumps failure

    International Nuclear Information System (INIS)

    One of the main requirements of the safety analysis report of tajoura research reactor is the thermal hydraulic analysis and the determination of the maximum fuel surface (clad) temperatures during the cut-off of the electrical power and failure of the primary circuit pumps. This paper is concerned with the thermal hydraulic analysis of the tajoura reactor and the calculation of the fuel and coolant temperatures. The objective of the study is to asses the possibility of cooling the reactor core by the emergency tank during the 1st minute after pumps failure and by natural convection after the automatic opening of the natural convection valves. the results of the present study show that the reactor is cooled properly by the primary circuit flow during normal operation with the maximum power of 10 MW, and that the emergency tank and natural convection provide sufficient cooling of the reactor after pump failure

  17. Primary heat transport pump trip by ground fault (deterioration of insulation in the cable quick disconnect)

    International Nuclear Information System (INIS)

    At 08:29 Sept. 1, 1988, Wolsong unit 1 was operating at 100% full power when a primary heat transport pump was suddenly tripped by breaker trip due to ground fault in the power distribution connector assembly. Soon after the pump trip, the reactor was shut down automatically on low heat transport flow. Operators tried to restart the pump twice but failed. A field operator reported to the shift supervisor that he found an electrical spark and smoke at the vicinity of the pump when the pump started to run. Inspection showed that a power distribution connector assembly for making fast and easy power connections to the PHT pump motor, 3312-PM2, was damaged severely by thermal shock. Particularly, broken parts of the insulating plug flew away across the boiler room and dropped to the floor. Direct causes of the failure were bad contact and deterioration of integrity along the creep paths between the insulating plug and the connector housing. The failed connector assembly had been used for more than 7 years. Its status had been checked infrequently during the in-service period. The standard torque value was not applied to the installation of connectors. Therefore, we concluded that long term inservice in combinations of application of improper torque value induced failure of insulation. This paper describes the scenarios, causes of the event and corrective actions to prevent recurrence of this event. (author)

  18. Seismic analysis of primary sodium pump of prototype fast breeder reactor

    International Nuclear Information System (INIS)

    This paper deals with seismic analysis of primary sodium pump of 500 MWe Prototype Fast Breeder Reactor (PFBR) by time history analysis. The associated fluid mechanics equations for determining stiffness coefficients for hydrostatic bearing (HSB) are formulated and solved by integrating with the governing structural dynamics equations. Thus, the stiffness coefficients of HSB are computed as function of eccentricity, speed and angular orientation of shaft at every solution time step. The maximum stress intensity values in the flywheel-motor support shell, pump shell and shaft are insignificant (<20 MPa). Hence, the structural integrity is assured for pump parts. The seizure of pump is found to be a critical issue under seismic events. The eccentricity of 60 μ experienced by the shaft during normal operation, increases to 250 μ under SSE. Since it is < 400 μ, the radial clearance, there is no problem of pump seizure. However, at speeds lower than 265 rpm, the eccentricity of shaft is higher than radial clearance and hence shaft can impact on the shell. Under OBE, up to 20 % speed (∼120 rpm), there is no impact. The peak impact force experienced by shaft and shell at HSB at 235 rpm under SSE is < 3 t, which may not cause pump seizure. This needs to be confirmed by experiments. (author)

  19. PLC-Based Pressure Control in Multi-Pump Applications

    Directory of Open Access Journals (Sweden)

    Vodovozov Valery

    2015-12-01

    Full Text Available The paper is devoted to the centrifugal pumps represented the most popular type of pumping equipment used in different areas. The pressure control approach for variable speed driven (VSD parallel connected centrifugal pumps is reported. The goal of the study is optimization of some quality indices, such as efficiency, consumed power, productivity, energy carrier temperature, heat irradiation, etc. One of them – efficiency – has been studied in the paper more carefully. The mathematical model of pumping process is discussed and a vector-matrix description of the multi-pump application is given. The program-based pressure control system is developed which productivity is changed by regulating the number of working pumps. The paper introduces new pressure control algorithms based on the working point estimation intended for programmable logical controllers (PLC. Experiments prove correctness of the offered methodology.

  20. The replacement of an electromagnetic primary sodium sampling pump in the Fast Flux Test Facility

    International Nuclear Information System (INIS)

    On November 16, 1984 a leak was discovered in one of the Fast Flux Test Facility (FFTF) Primary Sodium Sampling System electromagnetic pumps. The leak was discovered in the course of routine cell entry to investigate a shorted trace heat element. The purpose of this paper is to describe the circumstances surrounding the occurrence of the leak, the actions taken to replace the damaged pump and the additional steps which were necessary to return the plant to power. In addition, the processes involved in producing the leak are described briefly. The relative ease of recovery from this incident is indicative of the overall feasibility of the Liquid Metal Reactor (LMR) operational concept

  1. Model Based Fault Detection in a Centrifugal Pump Application

    DEFF Research Database (Denmark)

    Kallesøe, Carsten; Cocquempot, Vincent; Izadi-Zamanabadi, Roozbeh

    2006-01-01

    A model based approach for fault detection in a centrifugal pump, driven by an induction motor, is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, observer design and Analytical Redundancy Relation (ARR) design. Structural considerations...... the algorithm is capable of detecting four different faults in the mechanical and hydraulic parts of the pump....

  2. Integral forged pump casing for the primary coolant circuit of a nuclear reactor: Development in design, forging technology, and material

    International Nuclear Information System (INIS)

    Developments in the forging of large casings for primary circuit coolant pumps for light water reactors in Germany are demonstrated beginning with the multiple forging fabricated version and ending with the integral forged type. This version is the result of the joint efforts of the pump manufacturer and the forgemaster after a cost-gain evaluation and represents an optimum solution in view of its functional and economical performance and also considering the high requirements for mechanical-technological properties, including homogeneity of the material. The development from 22 NiMoCr 3 7/A 508 Class 2 to 20 MnMoNi 5 5/A 508 Class 3 and their optimization will be demonstrated. This development is based mainly on minimizing the sulfur content and on vacuum carbon deoxidation (VCD), which results in a reduction of the A-segregations, in improving fracture toughness and isotropy, and in the desired fine-grain structure

  3. Development of an 85,000 gpm (19,303 m3/h) LMFBR primary pump

    International Nuclear Information System (INIS)

    The development of an 85,000 gpm two-stage primary pump for liquid metal fast breeder reactor (LMFBR) applications is described. The design was supported by air and cavitation model testing of the hyraulics, and development and feature testing of the level control system and the adjustable frequency solid state power supply. Important fabrication and water test items are also discussed, along with some unique assembly tooling requirements

  4. Evaluation on the fretting abrasion of heat-transfer tubes of the integrated IHX/primary sodium pump. 1. Workrate analyses model

    International Nuclear Information System (INIS)

    The cost minimization of commercialized FBR plant systems requires the integration of an intermediate-heat-exchanger (IHX) and a primary sodium mechanical pump into one component. The pump is installed in the center of the integrated component and heat transfer tubes surround the pump. Primary sodium flows down inside the heat transfer tubes and secondary sodium flows up outside the tubes in a zigzag. Therefore, the pump rotation and sodium flow induce the vibration of heat transfer tubes and it leads the tubes to fretting wearing against support plates. Then the tube wearing must be evaluated to confirm its integrity during the plant life span (60 years). However, the knowledge of the pump rotation influence on tube wearing is not sufficiently acquired because the integrated component is a new concept in JNC. To evaluate the tube fretting wearing ratio due to the pump rotation, a new calculation model of FINAS was composed. In the first place, the beam vibration analysis model of a pump shaft, shells, tube bundle etc. of the integrated component reveals its properties such as frequency, amplitude and vibration mode. In the second place, based on the above mentioned vibration analysis, the frequency and amplitude of abrasion between the tubes and support plates can be obtained by a contact analysis model of FINAS. Eventually, this calculation shows that the tube wearing will not affect the tube integrity during the plant life time. However further evaluation by more detailed analysis and abrasion tests are needed to obtain more accurate results. (author)

  5. Analysis of a single primary coolant pump trip scenario in a PHWR

    International Nuclear Information System (INIS)

    This paper addresses the analysis of a single primary coolant pump (PCP) trip scenario in a 220 MWe Indian pressurized heavy water reactor (PHWR). The analysis is carried out using a lumped parameter model. The time dependent mass, momentum and energy for conservation equations for the primary system are solved using finite difference scheme. The predictions of the model for the time required to reach the over-pressure trip value was in good agreement with the plant data. Parametric studies are carried out to study the influences of the isolation of the failed branch and a delay in the trip of the diagonally opposite PCP. (author). 2 refs., 13 figs., 1 tab

  6. Key techniques for space-based solar pumped semiconductor lasers

    Science.gov (United States)

    He, Yang; Xiong, Sheng-jun; Liu, Xiao-long; Han, Wei-hua

    2014-12-01

    In space, the absence of atmospheric turbulence, absorption, dispersion and aerosol factors on laser transmission. Therefore, space-based laser has important values in satellite communication, satellite attitude controlling, space debris clearing, and long distance energy transmission, etc. On the other hand, solar energy is a kind of clean and renewable resources, the average intensity of solar irradiation on the earth is 1353W/m2, and it is even higher in space. Therefore, the space-based solar pumped lasers has attracted much research in recent years, most research focuses on solar pumped solid state lasers and solar pumped fiber lasers. The two lasing principle is based on stimulated emission of the rare earth ions such as Nd, Yb, Cr. The rare earth ions absorb light only in narrow bands. This leads to inefficient absorption of the broad-band solar spectrum, and increases the system heating load, which make the system solar to laser power conversion efficiency very low. As a solar pumped semiconductor lasers could absorb all photons with energy greater than the bandgap. Thus, solar pumped semiconductor lasers could have considerably higher efficiencies than other solar pumped lasers. Besides, solar pumped semiconductor lasers has smaller volume chip, simpler structure and better heat dissipation, it can be mounted on a small satellite platform, can compose satellite array, which can greatly improve the output power of the system, and have flexible character. This paper summarizes the research progress of space-based solar pumped semiconductor lasers, analyses of the key technologies based on several application areas, including the processing of semiconductor chip, the design of small and efficient solar condenser, and the cooling system of lasers, etc. We conclude that the solar pumped vertical cavity surface-emitting semiconductor lasers will have a wide application prospects in the space.

  7. Collapse characteristics of primary heat transport (PHT) pump discharge elbow of an Indian PHWR

    International Nuclear Information System (INIS)

    The primary heat transport (PHT) pump and associated piping of an Indian PHWR is a Class 1 component and can be subjected to a high magnitude of loadings during an earthquake. The PHT pump discharge elbow is an important component. Therefore, the determination of maximum load carrying capacity or collapse moment of the elbow is necessary in order to ensure its structural integrity. The effect of internal pressure on collapse moment was investigated. Through-wall longitudinal cracks of different sizes were postulated in the crown of the elbow and the fracture parameters were determined under internal pressure by linear static finite element analysis. The crack mouth opening displacements (CMODs) were obtained for internal pressure and a procedure for calculating elastic J-integral was established. The crack opening areas were found out to estimate the leak rate of the coolant. Collapse load was obtained for cracked elbow. (author). 6 refs., 6 figs

  8. The influence of hospital drug formulary policies on the prescribing patterns of proton pump inhibitors in primary care

    DEFF Research Database (Denmark)

    Larsen, Michael Due; Schou, Mette; Kristiansen, Anja Sparre;

    2014-01-01

    patterns after discharge. METHODS: This register study was conducted at Odense University Hospital, Denmark, and by use of pharmacy dispensing data and a hospital-based pharmacoepidemiological database, the medication regimens of patients were followed across hospitalisation. The influence of hospital drug......AIM: This study had two aims: Firstly, to describe how prescriptions for proton pump inhibitor (PPI) in primary care were influenced by a change of the hospital drug policy, and secondly, to describe if a large discount on an expensive PPI (esomeprazole) to a hospital would influence prescribing...... policy on prescribings in primary care was measured by the likelihood of having a high-cost PPI prescribed before and after change of drug policy. RESULTS: In total, 9,341 hospital stays in 2009 and 2010 were included. The probability of a patient to be prescribed an expensive PPI after discharge...

  9. Leakage of pump bearing oil into the PFR primary sodium, June 1991

    International Nuclear Information System (INIS)

    During the period 25-29 June 1991 a total of 35 l of lubricating oil from the bearing of one of the PFR primary pumps leaked into the primary sodium. The cause was a depressurization of the oil drains tank. Overheating of the affected bearing was observed, and the reactor was tripped manually. The main consequences of the event were contamination of the sodium, partial blockage of the pump outlet filters, and small increases in the outlet temperatures from some of the fuel subassemblies. Contamination of the sodium was removed by operation of the primary cold trap without difficulty. During 1992 the three filter assemblies were removed from the reactor and examined. They were found to be partly blocked with deposits incorporating carbon. The filter panels were replaced, and the assemblies restored to the reactor. Examination of a number of fuel assemblies showed deposits on the inlet filters of those which had exhibited temperature increases prior to shutdown, but none on those which had not. There were also fine deposits on the surfaces of some of the fuel pins. There was no evidence of any damage to the fuel. Experiments were conducted to demonstrate that the coolant flow rate through the remaining subassemblies was acceptable. Tests in a Russian experimental rig clarified certain important aspects of the behaviour of oil in sodium. As a result of this and other work permission was given by the safety authorities, and the reactor was restarted at the end of December 1992. (author)

  10. Novel sucker rod pumping system based on linear motor technology

    Institute of Scientific and Technical Information of China (English)

    李立毅; 李立清; 吴红星; 胡余生; 邹积岩

    2004-01-01

    Obtaining petroleum at the cost of electrical energy is a common problem in almost all oil fields, and it is mainly caused by low duty radio of induction motor used in beam pumping units. Traditional beam-pumping units have many intrinsic disadvantages such as low efficiency, complex transmission devices, poor flexibility,tremendous volume and weight in long stroke, etc. Therefore, a novel direct driven linear electromagnetic pumping unit (EMPU) has been developed by combining oil extraction technology with linear motor technology. The thrust of EMPU matches the changing of suspension center load to improve the system efficiency and cut down the consumption of energy. Based on previous experience, a small-scale prototype was developed and a simulation was conducted with it. Both theoretical analyses and experimental study showed that the problems exiting in beam pumping units can be solved with EMPU system, and this is a new method which can be used to solve high energy waste in oil fields.

  11. Predictive Reliability Assessment of the Automatic Clutch on a Primary Sodium Pump Drive

    International Nuclear Information System (INIS)

    This paper examines the reliability of a group of three clutch couplings each mounted between a pony motor and the main drive for the primary sodium pumps. The sodium pumps specification requires that continuously running AC pony motors be fitted to give a guaranteed 10% drive to the pumps in the event of a main supply failure. The drive to the main shaft is via 3 : 1 reduction gearing such that a six pole pony motor running at 300 rpm would drive the main shaft at 100 rpm i.e., 10% of its rated speed. In order that the pony motor drive could be permanently energised during normal operation a free wheeling clutch is fitted between the motor and the reduction gearing. The type of clutch chosen is. the Synchro-Self Shifting (SSS) clutch, shown in Figure 1. This type of clutch has proved itself under fairly onerous operating conditions, but is normally mounted on a horizontal driving shaft whereas in this case because of space limitations, it is necessary to mount it vertically. The reliability target set is that the chance of losing all three independent back-up pony motor drives on loss of main supplies should fall within the 10-5 - 10-6 band. Since the electrical supplies and other parts of the pony motor drives have been assessed within this target and some doubts expressed about the clutch it was now necessary to look at this in some detail

  12. Rapidly increasing use of proton pump inhibitors prescribed in primary care: a nationwide observational study

    DEFF Research Database (Denmark)

    Haastrup, Peter; Jarbøl, Dorte Ejg; Hansen, Jane Møller

    not been a change in indications for use of PPIs in the same time range. Use of ulcerogenic drugs among the elderly has stagnated. Reimbursement modifications do not seem to have had a substantial influence on the steadily increasing use of PPIs. Conclusions: Use of PPIs has increased substantially...... covering the entire Danish population of currently 5.5 million inhabitants. The register was searched September 2012 for the ADs proton-pump inhibitors (PPIs) and histamine-2-receptor antagonists. The variables turnover, paid reimbursement, volume sold, sector (primary vs. hospital), age, gender and number...... prophylaxis could be an indication for prescribing ADs to that age group. Results: PPIs are the far most commonly prescribed AD and 96.5 % are prescribed in primary care. Use of PPIs has increased by 243 % through the past decade. Both number of users and the average individual use has increased. There has...

  13. Study of activity build-up in primary coolant pump casing vent lines

    International Nuclear Information System (INIS)

    Kaiga Generating Station (KGS) Unit-II is a Standardized Pressurised Heavy Water Reactor with 220 MWe capacity and is located at Kaiga in Karnataka. Radioactive sources produced in nuclear reactor include fission products and activation products. Fission products are produced in the nuclear fuel UO2 during fission and confined to the fuel during normal operation of the plant. These products are likely to come out of the fuel to the primary coolant during the system depressurization due to presence of micro fissures in fuel cladding. Activation products are produced in the reactor core due to activation of impurities by neutrons, present in the primary coolant and in the reactor core components. The fission products and activation products circulate in the primary Heat Transport system and settles in specific out of core locations of the system equipment or components. The deposited radionuclides in system components become a source of radiation exposures in accessible areas. Radiological surveillance of reactor building areas is carried out at regular intervals to identify the hot spots on PHT system equipment to keep personnel exposures ALARA during maintenance activities. Radiological survey of reactor building areas 48 hours after shutdown showed the presence of significant hot spots on primary circulating pump (PCP) casing Vent lines in pump room. The radiation levels on PCP casing vent lines showed increasing trend over the past four months. Maximum radiation field on PCP-2 Casing Vent line was observed to be 770 mSv/h 3 hours after shutdown of the reactor. Major sources for build-up of activity on PCP casing Vent lines were Xenon-133, Iodine-131 and Antimony-122 and 124. (author)

  14. The numerical simulation based on CFD of hydraulic turbine pump

    Science.gov (United States)

    Duan, X. H.; Kong, F. Y.; Liu, Y. Y.; Zhao, R. J.; Hu, Q. L.

    2016-05-01

    As the functions of hydraulic turbine pump including self-adjusting and compensation with each other, it is far-reaching to analyze its internal flow by the numerical simulation based on CFD, mainly including the pressure field and the velocity field in hydraulic turbine and pump.The three-dimensional models of hydraulic turbine pump are made by Pro/Engineer software;the internal flow fields in hydraulic turbine and pump are simulated numerically by CFX ANSYS software. According to the results of the numerical simulation in design condition, the pressure field and the velocity field in hydraulic turbine and pump are analyzed respectively .The findings show that the static pressure decreases systematically and the pressure gradient is obvious in flow area of hydraulic turbine; the static pressure increases gradually in pump. The flow trace is regular in suction chamber and flume without spiral trace. However, there are irregular traces in the turbine runner channels which contrary to that in flow area of impeller. Most of traces in the flow area of draft tube are spiral.

  15. Experimental performance evaluation of heat pump-based steam supply system

    Science.gov (United States)

    Kaida, T.; Sakuraba, I.; Hashimoto, K.; Hasegawa, H.

    2015-08-01

    Heat pumps have become increasingly important as a technology to reduce primary energy consumption and greenhouse effect gas emission. They are presently used mainly on residential air-conditioning and domestic hot water and are expected to spread to industrial heating processes. In 2011, Kobe Steel, Ltd. developed and commercialized two heat pump- based steam supply systems; the high efficiency steam supply system with a steam temperature of 120°C (SGH120) and the system which enables a steam temperature of 165°C (sGh165). For promoting the spread of these industrial heat pumps and enhancing the reliability of them, we investigate experimentally steam generation rate, energy efficiency and controlled performance of the SGH165 under various operating conditions on the assumption of actual different industrial processes, and evaluate technical possibilities for better performance.

  16. Peristaltic pump-based low range pressure sensor calibration system

    Science.gov (United States)

    Vinayakumar, K. B.; Naveen Kumar, G.; Nayak, M. M.; Dinesh, N. S.; Rajanna, K.

    2015-11-01

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

  17. Peristaltic pump-based low range pressure sensor calibration system

    International Nuclear Information System (INIS)

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory

  18. Peristaltic pump-based low range pressure sensor calibration system.

    Science.gov (United States)

    Vinayakumar, K B; Naveen Kumar, G; Nayak, M M; Dinesh, N S; Rajanna, K

    2015-11-01

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory. PMID:26628178

  19. Peristaltic pump-based low range pressure sensor calibration system

    Energy Technology Data Exchange (ETDEWEB)

    Vinayakumar, K. B. [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 5600012 (India); Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore 5600012 (India); Naveen Kumar, G.; Rajanna, K., E-mail: kraj@isu.iisc.ernet.in, E-mail: krajanna2011@gmail.com [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 5600012 (India); Nayak, M. M. [Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore 5600012 (India); Dinesh, N. S. [Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore 5600012 (India)

    2015-11-15

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

  20. Pumping characteristics of Ti-based non-evaporable getter

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Yan; WEI; Xiu-ying; XIONG; Yu-hua; QIN; Guang-rong

    2005-01-01

    The application of non-evaporable getters is increasing, they have been widely used in sealed-off vacuum or controlled atmosphere devices. A new type of Ti-based sintered non-evaporable getter has been studied. The room temperature pumping speeds under three activation processes for H2 were measured as a function of sorbed gas quantities in this paper. At the same time, the optimal activation processes were discussed. The results indicate that the getter combines high porosity and large specific surface area which confirm good performances at room temperature. The threshold of activation temperature is about 500 ℃ and optimal pumping speed and pumping capacity can be achieved with activation temperature around 600℃ for 30 min. Besides, different configurations can be available in accordance with requirements.

  1. An Alternating Current Electroosmotic Pump Based on Conical Nanopore Membranes.

    Science.gov (United States)

    Wu, Xiaojian; Ramiah Rajasekaran, Pradeep; Martin, Charles R

    2016-04-26

    Electroosmotic flow (EOF) is used to pump solutions through microfluidic devices and capillary electrophoresis columns. We describe here an EOF pump based on membrane EOF rectification, an electrokinetic phenomenon we recently described. EOF rectification requires membranes with asymmetrically shaped pores, and conical pores in a polymeric membrane were used here. We show here that solution flow through the membrane can be achieved by applying a symmetrical sinusoidal voltage waveform across the membrane. This is possible because the alternating current (AC) carried by ions through the pore is rectified, and we previously showed that rectified currents yield EOF rectification. We have investigated the effect of both the magnitude and frequency of the voltage waveform on flow rate through the membrane, and we have measured the maximum operating pressure. Finally, we show that operating in AC mode offers potential advantages relative to conventional DC-mode EOF pumps. PMID:27046145

  2. Optimization of centrifugal pump cavitation performance based on CFD

    Science.gov (United States)

    Xie, S. F.; Wang, Y.; Liu, Z. C.; Zhu, Z. T.; Ning, C.; Zhao, L. F.

    2015-01-01

    In order to further improve the cavitation performance of a centrifugal pump, slots on impeller blade near inlet were studied and six groups of hydraulic model were designed. Base on cavitating flow feature inside a centrifugal pump, bubble growth and implosion are calculated from the Rayleigh-Plesset equation which describes the dynamic behavior of spherical bubble and RNG κ-epsilon model was employed to simulate and analyze the internal two-phase flow of the model pump under the same conditions. The simulation results show that slots on blade near inlet could improve the cavitation performance and cavitation performance improvement of the second group was more obvious. Under the same conditions, the pressure on the back of blade near inlet was higher than the pressure on the back of unmodified blade near inlet, and energy distribution in the flow channel between the two blades was more uniform with a small change of head.

  3. Rapidly increasing prescribing of proton pump inhibitors in primary care despite interventions

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja Skov; Zwisler, Jon Eik;

    2014-01-01

    and 2011 and association with age and gender of users along with the impact of interventions on the prescribing of drug subgroups are analysed. Results: 96.8% of all antisecretory drugs sold are proton pump inhibitors (PPIs) and 94.4% of the PPIs are prescribed in primary care. Prescribing of PPIs has...... increased substantially during the past decade. Both number of users and the average individual use have increased. The prescribing of ulcerogenic drugs to the elderly has stagnated in the same time range. Reimbursement modifications and scientific guidelines do not seem to have had a substantial influence...... on the steadily increasing prescribing of PPIs. Conclusion: Use of PPIs has increased substantially during the past decade, without a change in indications for use of PPIs in the same time range. Interventions to enhance adherence to guidelines and promote rational use of PPIs do not seem to have had...

  4. Study of an electromagnetic pump applied to a primary main pump of a large scale sodium cooled reactor

    International Nuclear Information System (INIS)

    This paper describes a future innovative design options with a parallel electromagnetic pump (EMP) system as the main circulating pump of the JSFR design. A conceptual design of EMPs integrated with an intermediate heat exchanger (IHX) is carried out. The major design parameters are consistent with the current JSFR design, where the main flow rate is 630 m3/min and the flow halving time is the same of the mechanical pump with the similar reliability. As a result of several design studies, a five parallel EMPs with IHX system has been selected from the geometry suitability for JSFR design. The EMP advantages comparing with mechanical pumps are investigated from the views of in-service inspection, maintenance and reliability. Numerical analysis with two dimensional MHD codes is conducted on a former experiment of a 160 m3/min flow rate EMP. The overall trend of the experimental data and the numerical results agrees with that in small-scale EMPs. However, the difference between the experimental data and the numerical results seems larger compared with the small-scale EMPs, which comes from large magnetic Reynolds number and interaction parameter of 160 m3/min EMP. (author)

  5. A Physically Based Model for Air-Lift Pumping

    Science.gov (United States)

    FrançOis, Odile; Gilmore, Tyler; Pinto, Michael J.; Gorelick, Steven M.

    1996-08-01

    A predictive, physically based model for pumping water from a well using air injection (air-lift pumping) was developed for the range of flow rates that we explored in a series of laboratory experiments. The goal was to determine the air flow rate required to pump a specific flow rate of water in a given well, designed for in-well air stripping of volatile organic compounds from an aquifer. The model was validated against original laboratory data as well as data from the literature. A laboratory air-lift system was constructed that consisted of a 70-foot-long (21-m-long) pipe, 5.5 inches (14 cm) inside diameter, in which an air line of 1.3 inches (3.3 cm) outside diameter was placed with its bottom at different elevations above the base of the long pipe. Experiments were conducted for different levels of submergence, with water-pumping rates ranging from 5 to 70 gallons/min (0.32-4.4 L/s), and air flow ranging from 7 to 38 standard cubic feet/min (0.2-1.1 m3 STP/min). The theoretical approach adopted in the model was based on an analysis of the system as a one-dimensional two-phase flow problem. The expression for the pressure gradient includes inertial energy terms, friction, and gas expansion versus elevation. Data analysis revealed that application of the usual drift-flux model to estimate the air void fraction is not adequate for the observed flow patterns: either slug or churn flow. We propose a modified drift-flux model that accurately predicts air-lift pumping requirements for a range of conditions representative of in-well air-stripping operations.

  6. Centrifugal Force Based Magnetic Micro-Pump Driven by Rotating Magnetic Fields

    International Nuclear Information System (INIS)

    This paper presents a centrifugal force based magnetic micro-pump for the pumping of blood. Most blood pumps are driven by an electrical motor with wired control. To develop a wireless and battery-free blood pump, the proposed pump is controlled by external rotating magnetic fields with a synchronized impeller. Synchronization occurs because the rotor is divided into multi-stage impeller parts and NdFeB permanent magnet. Finally, liquid is discharged by the centrifugal force of multi-stage impeller. The proposed pump length is 30 mm long and 19 mm in diameter which much smaller than currently pumps; however, its pumping ability satisfies the requirement for a blood pump. The maximum pressure is 120 mmHg and the maximum flow rate is 5000ml/min at 100 Hz. The advantage of the proposed pump is that the general mechanical problems of a normal blood pump are eliminated by the proposed driving mechanism.

  7. A MEMS-based valveless impedance pump utilizing electromagnetic actuation

    International Nuclear Information System (INIS)

    This study presents a planar valveless impedance-based micro pump for biomedical applications. The micro pump comprises four major components, namely a lower glass substrate containing a copper micro coil, a microchannel, an upper glass cover plate and a PDMS diaphragm with a magnet mounted on its upper surface. When a current is passed through the micro coil, an electromagnetic force is established between the coil and the magnet. The resulting deflection of the PDMS diaphragm creates an acoustic impedance mismatch within the microchannel, which results in a net flow. The performance of the micro pump is characterized both experimentally and numerically using Ansoft/Maxwell3D FEA software. The results show that the mechanical integrity of the micro pump is assured provided that the diaphragm deflection does not exceed 110 µm. This deflection is obtained by supplying the micro coil with an input current of 0.6 A, and results in a flow rate of 7.2 ml min−1 when the PDMS membrane is driven by an actuating frequency of 200 Hz

  8. A MEMS-based valveless impedance pump utilizing electromagnetic actuation

    Science.gov (United States)

    Lee, Chia-Yen; Chang, Hsien-Tsung; Wen, Chih-Yung

    2008-03-01

    This study presents a planar valveless impedance-based micro pump for biomedical applications. The micro pump comprises four major components, namely a lower glass substrate containing a copper micro coil, a microchannel, an upper glass cover plate and a PDMS diaphragm with a magnet mounted on its upper surface. When a current is passed through the micro coil, an electromagnetic force is established between the coil and the magnet. The resulting deflection of the PDMS diaphragm creates an acoustic impedance mismatch within the microchannel, which results in a net flow. The performance of the micro pump is characterized both experimentally and numerically using Ansoft/Maxwell3D FEA software. The results show that the mechanical integrity of the micro pump is assured provided that the diaphragm deflection does not exceed 110 µm. This deflection is obtained by supplying the micro coil with an input current of 0.6 A, and results in a flow rate of 7.2 ml min-1 when the PDMS membrane is driven by an actuating frequency of 200 Hz.

  9. Evaluation on the fretting abrasion of heat-transfer tubes of the integrated IHX/primary sodium pump. 2. Fretting wearing analyses

    International Nuclear Information System (INIS)

    A primary sodium pump is installed in the center of an integrated component and heat transfer tubes surround the pump. Then, the pump rotation induces the vibration of heat transfer tubes and it leads the tubes to fretting wearing against support plates. Therefore, the tube wearing must be evaluated to confirm its integrity during the plant life span (60 years). This report describes the results of the tube wearing analysis by using vibration and wearing calculation models. In the first place, the vibration analysis of a pump shaft, shells, tube bundle etc. of the integrated component reveals its properties such as frequency, amplitude and vibration mode. In the second place, based on the above mentioned vibration analysis, the wearing analysis model shows the frequency and amplitude of the fretting wearing between tubes and support plates and the wearing depth of tubes. The amplitude of the pump vibration, vibration transmission paths and the contact condition between tubes and support plates especially affect the tube wearing, then the wearing evaluation needs that conservative calculation conditions must be found out by surveying these parameters. This calculation result indicates that the tube abrasion does not affect the tube integrity during the plant life time. However further evaluation by more detailed analysis and vibration and wearing tests are needed to acquire more accurate results. (author)

  10. Performance analysis of photovoltaic based submersible water pump

    Directory of Open Access Journals (Sweden)

    Shiv Lal

    2013-04-01

    Full Text Available The performance of a photovoltaic (PV array based water pumping system situated at Kota Rajasthan (25.18 N and 75.83 E, India has been studied. A 2hp DC motor with 2200W (10 panels of each 225W have been used for discharge 30 m water head. The maximum discharge logged 163litre/minute between 11AM to 2PM at PV power output between 75 to 85W/m2and the system is operating approximately 8 hours in the of November of the winter season. The full day discharge has found 70995litre and it is more than the average discharge given by the manufacturer at 50m depth. It is revealed that PV array based water pumping system is suitable and feasible option for off-grid and drip irrigation system like the interior area of Kota, where clear sky days are more than 250 in a year.

  11. Refurbishment of primary coolant pump stuffing boxes for RAPS-1,2

    International Nuclear Information System (INIS)

    Primary coolant pumps (PCPs) are the most critical equipment in PHWR and stuffing box is one of the critical parts of the PCP. The stuffing box houses the mechanical seals, radial bearings, throttle bushings and stationary part of wearing ring. During overhauling of PCPs it was observed that the cracks are developing on the inside face of the stuffing box and at the bolt holes where the lower bearing housing is fixed. Since consequence of failure of stuffing box will be a break in primary system boundary a detailed investigation was carried out to find out cause of failure. An immediate procurement of these from OEM (Original Equipment Manufacturer) was not feasible and indigenous procurement of such a large and precision-machined PCP component would have called for extensive development work. Under the circumstances, the only immediate option left was to repair and re-use these failed stuffing boxes. However, repair of these stuffing boxes was considered to be very difficult job as weld repair could cause distortion and any other option was not found suitable. Since the industry was not geared up to produce such components, a decision to carry out a heavy weld build up after removing the cracks up to root, was taken after considering various other options. Major weld repair and subsequent machining was carried out successfully on four stuffing boxes and subsequently these have been put in to service. The paper covers the investigations done, various options considered, how the weld repairs were carried out and the salient features of the indigenous development taken up. (author)

  12. Analysis of primary coolant pump seal water distribution influence to chemical and volume system design

    International Nuclear Information System (INIS)

    The possible influences to Chemical and Volume Control System design caused by coolant pump seal water distribution are discussed. The essential reason is picked out in this paper. The temperature drop of charging flow at the regenerative heat exchanger outlet is calculated, and the feasible retrofits of the Chemical and Volume Control System are illustrated. The thermal hydraulic software Flowmaster 7.5 is employed to numerically investigate the possible capability of charging pump with different coolant pump seal requirements. (authors)

  13. Pipe flow of pumping wet shotcrete based on lubrication layer.

    Science.gov (United States)

    Chen, Lianjun; Liu, Guoming; Cheng, Weimin; Pan, Gang

    2016-01-01

    Wet shotcrete can reduce dust and improve supporting strength, however, safe and efficient pipage is a key technical part of wet shotcrete process. The paper studied the pipe flow law of wet shotcrete based on lubrication layer by build the experimental pumping circuit of wet shotcrete that can carry out a number of full-scale pumping tests. The experimental results show there was a linear relationship between pressure loss and flow rate. Combined with the Buckingham rheological equation, the computing equations of the yield shear stress and plastic viscosity were deduced through linear regression. A simple analytical method allowing for a rough estimation of the pumping pressure was proposed and used when considering the lubrication layer of wet shotcrete in pipes. In addition, two kinds of particulate distributive models were established along the time axial to analyze the formation of lubrication layer which is related with particles migration. By computational fluid dynamics simulation, the lubrication layer thickness of different mix proportions was estimated. A new method for measuring the thickness of lubrication layer was proposed to verify it by binarization processing. Finally, according to the comparative analysis of experiments, simulation and computed value, it can be seen that the lubrication layer plays a key role in the process of wet shotcrete flow and with the increase of lubrication layer thickness pipe pressure declines gradually. PMID:27386389

  14. The Association between Bile Salt Export Pump Single-Nucleotide Polymorphisms and Primary Biliary Cirrhosis Susceptibility and Ursodeoxycholic Acid Response

    OpenAIRE

    Rui-rui Chen; Yuan-jun Li; Xin-min Zhou; Lu Wang; Juan Xing; Shuang Han; Li-na Cui; Lin-hua Zheng; Kai-chun Wu; Yong-quan Shi; Zhe-yi Han; Ying Han; Dai-ming Fan

    2014-01-01

    Background. Primary biliary cirrhosis (PBC) is a chronic and progressive cholestasis liver disease. Bile salt export pump (BSEP) is the predominant bile salt efflux system of hepatocytes. BSEP gene has been attached great importance in the susceptibility of PBC and the response rate of ursodeoxycholic acid (UDCA) treatment of PBC patients. Methods. In this study, TaqMan assay was used to genotype four variants of BSEP, and the Barcelona criteria were used for evaluating the response rate of U...

  15. Phase Sensitive Amplifier Based on Ultrashort Pump Pulses

    CERN Document Server

    Gershikov, Alexander

    2016-01-01

    We demonstrate a narrow band phase sensitive amplifier in the pump degenerate configuration which employs ps pump pulses. Control of the amplifier bandwidth is achieved via changes of the pump spectral width. A phase sensitive gain between -6 and 6 decibels, with an overall system gain of 28dB was demonstrated.

  16. 10 CFR 830 Major Modification Determination for Replacement of ATR Primary Coolant Pumps and Motors

    Energy Technology Data Exchange (ETDEWEB)

    Noel Duckwitz

    2011-05-01

    The continued safe and reliable operation of the ATR is critical to the Department of Energy (DOE) Office of Nuclear Energy (NE) mission. While ATR is safely fulfilling current mission requirements, a variety of aging and obsolescence issues challenge ATR engineering and maintenance personnel’s capability to sustain ATR over the long term. First documented in a series of independent assessments, beginning with an OA Environmental Safety and Health Assessment conducted in 2003, the issues were validated in a detailed Material Condition Assessment (MCA) conducted as a part of the ATR Life Extension Program in 2007.Accordingly, near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE’s long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent subprojects. The first project will replace the existent diesel-electrical bus (E-3), switchgear, and the 50-year-old obsolescent marine diesels with commercial power that is backed with safety related emergency diesel generators, switchgear, and uninterruptible power supply (UPS). The second project, the subject of this major modification determination, will replace the four, obsolete, original primary coolant pumps (PCPs) and motors. Completion of this and the two other age-related projects (replacement of the ATR diesel bus [E-3] and switchgear and replacement of the existent emergency firewater injection system) will resolve major age-related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the project pre-conceptual design identified several issues that lead to the conclusion that the project is a major modification: 1. Evaluation Criteria #3 (Change of existing process). The proposed strategy for equipping the replacement PCPs with VFDs

  17. The results of an ultrasonic examination of a flywheel attached to a primary cooling pump in HANARO

    International Nuclear Information System (INIS)

    In HANARO, a multi-purpose research reactor of 30 MWth, the primary cooling system (PCS as below) is composed of two heat exchangers, two pumps, piping including valves and instruments for cooling the nuclear fission heat during a normal operation. At a loss of electric power, a flywheel attached to each pump motor shaft provides an inertia force to ensure a slow decrease in the coolant flow in order to prevent a fuel melting. During an operation at a normal speed, a flywheel has a sufficient kinetic energy to produce high-energy missiles, and excessive vibrations of the reactor coolant pump assembly. An excess speed of the pump rotor assembly during a transient increases both the potential energy for a failure and the kinetic energy of a flywheel. The safety consequences could be significant because of possible damage to the PCS, the containment, other equipments or systems important to its safety. This year we conducted an ultrasonic examination of a flywheel to verify its structural integrity during its second 10 years periodic in-service inspection period. This paper describes the results of the ultrasonic examination. It was confirmed that the structural integrity of each flywheel is maintained through the test results in that a marked defect was not found. (author)

  18. FPGA based pump speed measurement system for prototype fast breeder reactor

    International Nuclear Information System (INIS)

    In Prototype Fast Breeder Reactor (PFBR), the heat generated in the reactor core by nuclear fission is extracted by circulating liquid sodium through it using two Primary Sodium Pumps (PSP). The FPGA-based PSP Speed measurement system is a safety critical system provided to protect the reactor in the event of a PSP seizure. The function of the system is to measure the PSP speed and initiate safety action if there is a reduction in speed below a specified set point. Variable Reluctance Sensor (VRS) is used for measuring the PSP speed. This sensor outputs a voltage signal, whose amplitude and frequency are proportional to the pump speed. The frequency of the sensor signal is measured, translated to the pump speed, and compared with user-specified set points for generating the required alarm and trip (safety action) signals. This paper explains the system requirements, system architecture, implementation and qualification tests carried out on the system. Since the timing requirements on the system are stringent, a pipelined architecture is used for improving the system response time, which is detailed in this paper. Since the system is safety critical, various safety and failsafe features are incorporated in the system which are also explained. (author)

  19. Research on scheme of pumping energy-saving based on computer control technology

    Directory of Open Access Journals (Sweden)

    Chuan-Lin Li

    2016-01-01

    Full Text Available Energy conservation of pump station has attracted more and more attention. The scheme of pumping energy-saving based on computer control technology was explored in this study by taking the example of Da Zhang Zhuang pump station in Tianjin. The results showed that when efficient was improved by 1%, the 170,000 kWh power would be saved annually. This method was applicable for the other pump stations with same style. What’s more, for the pump stations which have already been controlled by computer program, it would be much more convenience that might be easy conducted in the near future.

  20. Research on scheme of pumping energy-saving based on computer control technology

    OpenAIRE

    Chuan-Lin Li; Shi-lei Ma; Hua Liu; Hai-yun Wu; Ping Gao; Fan Yang

    2016-01-01

    Energy conservation of pump station has attracted more and more attention. The scheme of pumping energy-saving based on computer control technology was explored in this study by taking the example of Da Zhang Zhuang pump station in Tianjin. The results showed that when efficient was improved by 1%, the 170,000 kWh power would be saved annually. This method was applicable for the other pump stations with same style. What’s more, for the pump stations which have already been controlled by compu...

  1. A fused side-pumping optical fiber coupler based on twisting

    Science.gov (United States)

    Yi, Bokai; Chang, Xinzu; Zhou, Xuanfeng; Chen, Zilun; Zhao, Guomin

    2014-12-01

    Pumping coupler technology is one of the critical technologies for high power laser and amplifier. Side-pumping technology can couple pumping beam into inner cladding of the double-clad fiber through the side of the fiber. Compared to the end-pumping technology by tapered fused bundle (TFB), it has many superiorities. That the signal fiber was not disconnected guarantees high transmission efficiency, providing the possibility of transmitting a high power signal. Additionally, the pump light is coupled into the double-cladding fiber all along the coupler's body (~5-10 cm long), which reduces the thermal effects caused by leakage of pumping light, resulting in high pump power handling capabilities. For the realization of reliable, rugged and efficient high power fiber amplifiers and fiber laser systems, a novel kind of fused side-pumping coupler based on twisting is developed. The complete simulations were carried out for the process of side-pumping. From detailed information about simulations, we found that the pump efficiencies, one of the vital parameters of pumping coupler, have a significant influence with coupling length, the numerical aperture (NA) and taper ratio of pump fiber. However, the diversification of the parameters drops the high transmission efficiency barely. Optimized the parameters in the simulations, the pump and signal coupling efficiencies are 97.3% and 99.4%, respectively. Based on theoretical analysis, the side-pumping coupler was demonstrated at the pump and signal coupling efficiencies are 91.2% and 98.4%, respectively. This fiber coupler can be implemented in almost any fiber laser or amplifier architecture.

  2. GaAs-based high temperature electrically pumped polariton laser

    International Nuclear Information System (INIS)

    Strong coupling effects and polariton lasing are observed at 155 K with an edge-emitting GaAs-based microcavity diode with a single Al0.31Ga0.69As/Al0.41Ga0.59As quantum well as the emitter. The threshold for polariton lasing is observed at 90 A/cm2, accompanied by a reduction of the emission linewidth to 0.85 meV and a blueshift of the emission wavelength by 0.89 meV. Polariton lasing is confirmed by the observation of a polariton population redistribution in momentum space and spatial coherence. Conventional photon lasing is recorded in the same device at higher pump powers

  3. Pump-stopping water hammer simulation based on RELAP5

    International Nuclear Information System (INIS)

    RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case

  4. Pump-stopping water hammer simulation based on RELAP5

    Science.gov (United States)

    Yi, W. S.; Jiang, J.; Li, D. D.; Lan, G.; Zhao, Z.

    2013-12-01

    RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case.

  5. Impeller-shaft connection, especially for a PWR primary coolant pump

    International Nuclear Information System (INIS)

    The pump has: - a rotation shaft - an impeller mounted on the shaft - a thermal barrier placed above the impeller. An hydrostatic bearing is mounted on the extension belt of the impeller the impeller-shaft connection is made by a fixation device, a centering device and a coupling transmission device

  6. The Impact of Critical Flow on the Primary Electron Beam Passage through Differentially Pumped Chamber

    Czech Academy of Sciences Publication Activity Database

    Maxa, J.; Neděla, Vilém

    2011-01-01

    Roč. 6, č. 1 (2011), s. 39-46. ISSN 1802-2308 R&D Projects: GA ČR GAP102/10/1410 Institutional research plan: CEZ:AV0Z20650511 Keywords : EREM * CAE * SolidWorks * Cosmos * FEI * differentially pumped chamber Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  7. Experimental and analytical investigations of primary coolant pump coastdown phenomena for the Jordan Research and Training Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Alatrash, Yazan [Advanced Nuclear Engineering System Department, Korea University of Science and Technology (UST), 217 Gajeong-ro Yuseong-gu, Daejeon 305-350 (Korea, Republic of); Kang, Han-ok; Yoon, Hyun-gi; Seo, Kyoungwoo; Chi, Dae-Young [Korea Atomic Energy Institute (KAERI), 989-111 Daeduk-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Yoon, Juhyeon, E-mail: yoonj@kaeri.re.kr [Korea Atomic Energy Institute (KAERI), 989-111 Daeduk-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Korea University of Science and Technology (UST), Daejeon (Korea, Republic of)

    2015-05-15

    Highlights: • Core flow coastdown phenomena of a research reactor are investigated experimentally. • The experimental dataset is well predicted by a simulation software package, MMS. • The validity and consistency of the experimental dataset are confirmed. • The designed coastdown half time is confirmed to be well above the design requirement. - Abstract: Many low-power research reactors including the Jordan Research and Training Reactor (JRTR) are designed to have a downward core flow during a normal operation mode for many convenient operating features. This design feature requires maintaining the downward core flow for a short period of time right after a loss of off-site power (LOOP) accident to guarantee nuclear fuel integrity. In the JRTR, a big flywheel is installed on a primary cooling system (PCS) pump shaft to passively provide the inertial downward core flow at an initial stage of the LOOP accident. The inertial pumping capability during the coastdown period is experimentally investigated to confirm whether the coastdown half time requirement given by safety analyses is being satisfied. The validity and consistency of the experimental dataset are evaluated using a simulation software package, modular modeling system (MMS). In the MMS simulation model, all of the design data that affect the pump coastdown behavior are reflected. The experimental dataset is well predicted by the MMS model, and is confirmed to be valid and consistent. The designed coastdown half time is confirmed to be well above the value required by safety analysis results. (wwwyoon@gmail.com)

  8. Experimental and analytical investigations of primary coolant pump coastdown phenomena for the Jordan Research and Training Reactor

    International Nuclear Information System (INIS)

    Highlights: • Core flow coastdown phenomena of a research reactor are investigated experimentally. • The experimental dataset is well predicted by a simulation software package, MMS. • The validity and consistency of the experimental dataset are confirmed. • The designed coastdown half time is confirmed to be well above the design requirement. - Abstract: Many low-power research reactors including the Jordan Research and Training Reactor (JRTR) are designed to have a downward core flow during a normal operation mode for many convenient operating features. This design feature requires maintaining the downward core flow for a short period of time right after a loss of off-site power (LOOP) accident to guarantee nuclear fuel integrity. In the JRTR, a big flywheel is installed on a primary cooling system (PCS) pump shaft to passively provide the inertial downward core flow at an initial stage of the LOOP accident. The inertial pumping capability during the coastdown period is experimentally investigated to confirm whether the coastdown half time requirement given by safety analyses is being satisfied. The validity and consistency of the experimental dataset are evaluated using a simulation software package, modular modeling system (MMS). In the MMS simulation model, all of the design data that affect the pump coastdown behavior are reflected. The experimental dataset is well predicted by the MMS model, and is confirmed to be valid and consistent. The designed coastdown half time is confirmed to be well above the value required by safety analysis results. (wwwyoon@gmail.com)

  9. Receptor kinase-mediated control of primary active proton pumping at the plasma membrane

    DEFF Research Database (Denmark)

    Fuglsang, AT; Kristensen, A; Cuin, TA;

    2014-01-01

    and in planta with PSY1R, a receptor kinase of the plasma membrane that serves as a receptor for the peptide growth hormone PSY1. The intracellular protein kinase domain of PSY1R phosphorylates AHA2/AHA1 at Thr-881, situated in the autoinhibitory Region I of the C-terminal domain. When expressed in a yeast......Acidification of the cell wall space outside the plasma membrane is required for plant growth and is the result of proton extrusion by the plasma membrane-localized H+ -ATPases. Here we show that the major plasma membrane proton pumps in Arabidopsis, AHA1 and AHA2, interact directly in vitro...... heterologous expression system, the introduction of a negative charge at this position caused pump activation. Application of PSY1 to plant seedlings induced rapid in planta phosphorylation at Thr-881, concomitant with an instantaneous increase in proton efflux from roots. The direct interaction between AHA2...

  10. Model Based Diagnosis of an Air Source Heat Pump

    OpenAIRE

    Alfredsson, Sandra

    2011-01-01

    The purpose of a heat pump is to control the temperature of an enclosed space. This is done by using heat exchange with a heat source, for example water, air, or ground. In the air source heat pump that has been studied during this master thesis, a refrigerant exchanges heat with the outdoor air and with a water distribution system. The heat pump is controlled through the circuit containing the refrigerant and it is therefore crucial that this circuit is functional. To ensure this, a diagnosi...

  11. Sol-Gel Based Polybenzimidazole Membranes for Hydrogen Pumping Devices

    Energy Technology Data Exchange (ETDEWEB)

    Benicewicz, Brian

    2014-02-26

    Electrochemical hydrogen pumping using a high temperature (>100°C) PBI membrane was demonstrated under non-humidified and humidified conditions at ambient pressures. Relatively low voltages were required to operate the pump over a wide range of hydrogen flow rates. The advantages of the high temperature capability were shown by operating the pump on reformate feed gas mixtures containing various amounts of CO and CO{sub 2}. Gas purity measurements on the cathode gas product were conducted and significant reductions in gas impurities were detected. The applicability of the PBI membrane for electrochemical hydrogen pumping and its durability under typical operating conditions was established with tests that lasted for nearly 4000 hours.

  12. Proton pump inhibitors in cirrhosis: Tradition or evidence based practice?

    Institute of Scientific and Technical Information of China (English)

    Francesca Lodato; Francesco Azzaroli; Maria Di Girolamo; Valentina Feletti; Paolo Cecinato; Andrea Lisotti; Davide Festi; Enrico Roda; Giuseppe Mazzella

    2008-01-01

    Proton Pump Inhibitors (PPI) are very effective in inhibiting acid secretion and are extensively used in many acid related diseases. They are also often used in patients with cirrhosis sometimes in the absence of a specific acid related disease, with the aim of preventing peptic complications in patients with variceal or hypertensive gastropathic bleeding receiving multidrug treatment. Contradicting reports support their use in cirrhosis and evidence of their efficacy in this condition is poor. Moreover there are convincing papers suggesting that acid secretion is reduced in patients with liver cirrhosis. With regard to H pylori infection, its prevalence in patients with cirrhosis is largely variable among different studies, and it seems that H pylori eradication does not prevent gastro-duodenal ulcer formation and bleeding. With regard to the prevention and treatment of oesophageal complications after banding or sclerotherapy of oesophageal varices, there is little evidence for a protective role of PPI. Moreover, due to liver metabolism of PPI, the dose of most available PPIs should be reduced in cirrhotics. In conclusion, the use of this class of drugs seems more habit related than evidence-based eventually leading to an increase in health costs.

  13. Residential gas heat pump assessment: A market-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, P.J.

    1995-09-01

    There has been considerable activity in recent years to develop technologies that could reduce or levelize residential and light-commercial building space cooling electrical use and heating/cooling energy use. For example, variable or multi-speed electric heat pumps, electric ground-source heat pumps, dual-fuel heat pumps, multi-function heat pumps, and electric cool storage concepts have been developed; and several types of gas heat pumps are emerging. A residential gas heat pump (GHP) benefits assessment is performed to assist gas utility and equipment manufacturer decision making on level of commitment to this technology. The methodology and generic types of results that can be generated are described. National market share is estimated using a market segmentation approach. The assessment design requires dividing the 334 Metropolitan Statistical Areas (MSAS) of the US into 42 market segments of relatively homogeneous weather and gas/electric rates (14 climate groupings by 3 rate groupings). Gas and electric rates for each MSA are evaluated to arrive at population-weighted rates for the market segments. GHPs are competed against 14 conventional equipment options in each homogeneous segment.

  14. A Novel All-optical Wavelength Converter Based on Self-pump Four-wave Mixing

    Institute of Scientific and Technical Information of China (English)

    CHEN Jianxiao; CHEN Zhangyuan; TAO Zhenning; WU Deming; XU Anshi; WANG Ziyu

    2002-01-01

    A novel scheme of all-optical wavelength converter(AOWC) based on dual pump four-wave mixing(DP-FWM) was demonstrated. To suppress the ASE noise of the semiconductor optical amplifier (SOA), one of the two pumps was generated interiorly from a loop laser constructed mainly by tunable optical filter and SOA. The theoretical model and some experimental results were presented.

  15. Transient stress-based and strain-based hemolysis estimation in a simplified blood pump.

    Science.gov (United States)

    Pauli, Lutz; Nam, Jaewook; Pasquali, Matteo; Behr, Marek

    2013-10-01

    We compare two approaches to numerical estimation of mechanical hemolysis in a simplified blood pump model. The stress-based model relies on the instantaneous shear stress in the blood flow, whereas the strain-based model uses an additional tensor equation to relate distortion of red blood cells to a shear stress measure. We use the newly proposed least-squares finite element method (LSFEM) to prevent negative concentration fields and show a stable and volume preserving LSFEM for the tensor equation. Application of both models to a simplified centrifugal blood pump at three different operating conditions shows that the stress-based model overestimates the rate of hemolysis. The strain-based model is found to deliver lower hemolysis rates because it incorporates a more detailed description of biophysical phenomena into the simulation process. PMID:23922311

  16. Electromagnetic liquid pistons for capillarity-based pumping.

    Science.gov (United States)

    Malouin, Bernard A; Vogel, Michael J; Olles, Joseph D; Cheng, Lili; Hirsa, Amir H

    2011-02-01

    The small scales associated with lab-on-a-chip technologies lend themselves well to capillarity-dominated phenomena. We demonstrate a new capillarity-dominated system where two adjoining ferrofluid droplets can behave as an electronically-controlled oscillator or switch by an appropriate balance of magnetic, capillary, and inertial forces. Their oscillatory motion can be exploited to displace a surrounding liquid (akin to an axial piston pump), forming electromagnetic "liquid pistons." Such ferrofluid pistons can pump a precise volume of liquid via finely tunable amplitudes (cf. pump stroke) or resonant frequencies (cf. pump speed) with no solid moving parts for long-term operation without wear in a small device. Furthermore, the rapid propagation of electromagnetic fields and the favorable scaling of capillary forces with size permit micron sized devices with very fast operating speeds (∼kHz). The pumping dynamics and performance of these liquid pistons is explored, with experimental measurements showing good agreement with a spherical cap model. While these liquid pistons may find numerous applications in micro- and mesoscale fluidic devices (e.g., remotely activated drug delivery), here we demonstrate the use of these liquid pistons in capillarity-dominated systems for chip-level, fast-acting adaptive liquid lenses with nearly perfect spherical interfaces. PMID:21127823

  17. Computational Fluid Dynamics-Based Design Optimization Method for Archimedes Screw Blood Pumps.

    Science.gov (United States)

    Yu, Hai; Janiga, Gábor; Thévenin, Dominique

    2016-04-01

    An optimization method suitable for improving the performance of Archimedes screw axial rotary blood pumps is described in the present article. In order to achieve a more robust design and to save computational resources, this method combines the advantages of the established pump design theory with modern computer-aided, computational fluid dynamics (CFD)-based design optimization (CFD-O) relying on evolutionary algorithms and computational fluid dynamics. The main purposes of this project are to: (i) integrate pump design theory within the already existing CFD-based optimization; (ii) demonstrate that the resulting procedure is suitable for optimizing an Archimedes screw blood pump in terms of efficiency. Results obtained in this study demonstrate that the developed tool is able to meet both objectives. Finally, the resulting level of hemolysis can be numerically assessed for the optimal design, as hemolysis is an issue of overwhelming importance for blood pumps. PMID:26526039

  18. Tritium gas transfer pump development

    International Nuclear Information System (INIS)

    Non-lubricated, hermetically sealed pumps for tritium service have been selected to replace Sprengel pumps in the existing Tritium Facility. These pumps will be the primary gas-transfer pumps in the planned Replacement Tritium Facility. The selected pumps are Metal Bellows Corporation's bellows pumps and Normetex scroll pumps. Pumping range for a Normetex/Metal Bellows system is from 0.01 torr suction to 2300 torr discharge. Performance characteristics of both pumps are presented. 10 figs

  19. Data from Sustainability Base Characterizing Hot Water Pump Differential Pressure Spikes for ACCEPT

    Data.gov (United States)

    National Aeronautics and Space Administration — During the heating season in Sustainability Base, a critical alarm associated with a hot water pump circulating heating water for the radiative system which...

  20. High-efficiency resonantly pumped 1550-nm fiber-based laser transmitter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — nLight proposes the development of high efficiency, high average power 1550-nm laser transmitter system that is based on Er-doped fiber amplifier resonantly pumped...

  1. Model-based Optimizing Control of a Water-to-Water Heat Pump Unit

    OpenAIRE

    Morten C. Svensson

    1996-01-01

    This paper outlines the basic principles of on-line model-based steady-state optimizing control of continuous processes, and illustrates how this control approach can be used to optimize the operating conditions of heat pumps.

  2. MEMS based pumped liquid cooling systems for micro/nano spacecraft thermal control

    Science.gov (United States)

    Birur, G. C.; Shakkottai, P.; Sur, T. W

    2001-01-01

    The objective is to develop MEMS based pumped liquid cooling system for removing over 20 W/cm squared from high power density microelectronics and science payloads considered for future micro/nano sciencecraft.

  3. Design development and testing of a solar PV pump based drip system for orchards

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.C.; Singh, A.K.; Ansari, S.; Vyas, S.K.; Dave, B.K. [Central Arid Zone Research Inst., Jodhpur (India)

    2003-03-01

    A Solar Photovoltaic (PV) pump operated drip irrigation system has been designed and developed for growing orchards in arid region considering different design parameters like pumps size, water requirements, the diurnal variation in the pressure of the pump due to change in irradiance and pressure compensation in the drippers. The system comprising a PV pump with 900 W{sub p} PV array and 800 W dc motor-pump mono-block, microfilter, main and sub-mains and three open-able low-pressure compensating drippers on each plant was field tested. The emission uniformity was observed to be 92-94% with discharge of 3.8 l/h in the pressure range of 70-100 kPa provided by the pump and thus the system could irrigate some 1 ha area within 2 h. Based on the performance of the PV pump and the drip system, it was inferred that about 5 ha area of orchard could be covered. The projected benefit-cost ratio for growing pomegranate orchards with such a system was evaluated to be above 2 even with the costly PV pump and therefore the system was considered to be an appropriate technology for the development of arid region. (Author)

  4. Microfluidic Pumping based on Traveling-Wave Dielectrophoresis

    OpenAIRE

    Liu, D.; Garimella, S V

    2009-01-01

    This article presents a microfluidic pumping approach using traveling-wave dielectrophoresis (twDEP) of microparticles. With this approach, the flow is generated directly in the microfluidic devices by inducing strong electromechanical effects in the fluid using integrated microelectrodes. The fluidic driving mechanisms due to the particle-fluid and particle-particle interactions under twDEP are analyzed, and the induced flow field is obtained from numerical simulations. Experimental measurem...

  5. Dynamic characterization of silicon nanowires using a terahertz optical asymmetric demultiplexer-based pump-probe scheme

    DEFF Research Database (Denmark)

    Ji, Hua; Cleary, C. S.; Dailey, J. M.;

    2012-01-01

    Dynamic phase and amplitude all-optical responses of silicon nanowires are characterized using a terahertz optical asymmetric demultiplexer (TOAD) based pump-probe scheme. Ultra-fast recovery is observed for moderate pump powers.......Dynamic phase and amplitude all-optical responses of silicon nanowires are characterized using a terahertz optical asymmetric demultiplexer (TOAD) based pump-probe scheme. Ultra-fast recovery is observed for moderate pump powers....

  6. Research on the Energy Consumption Evaluation and Energy Saving Technical Reconstruction of Centrifugal Pump System Based on Actual Demand

    OpenAIRE

    Luo Yin; Shouqi Yuan; Tang Yue; Yuan Jianping

    2013-01-01

    A new method for calculating the operational efficiency of a pumping station has been developed based on the integral principle and operation rules of the pump flow rate. To determine the energy saving space of a pumping system and to reflect the relationship between supply and demand, a new method for evaluating the energy consumption rate of a pump system has been developed based on the principle of an inverter-controlled water supply with varying pressures. These methods have been applied ...

  7. Presentation of accessibility equipment for primary pipings, IHX, pumps and appertaining manipulator tests

    International Nuclear Information System (INIS)

    Accessibility and inservice procedure of SNR-300 components are described. Due to the high radiation level in the primary system it was necessary to develop special equipment to permit access to the testing components. The pertinent examination methods for surveying welding seams are acoustic (ultrasonic) and optical procedures (TV cameras, surface crack tests). This can be done by remote-controlled manipulators and special devices, which can transport the inspection system by rails to the testing position. Presently, relatively limited experience exists for such remote-controlled handling in nuclear power plants. Thus model experiments were carried out on a model pipe section at INTERATOM. The performed test shows that the concept planned to perform inservice by using remote-controlled manipulators can be realized successfully. (author)

  8. Finite element method-based investigation of deformation of pump diaphragm and its influence on pump perfomance

    OpenAIRE

    Fernandez Mallart, Joana

    2009-01-01

    Diaphragm (membrane) pumps are reciprocating positive displacement pumps. Transport of liquid is achieved through reciprocating motion of the diaphragm. In the case of hydraulically actuated diaphragm pumps, diaphragm displacement is realized through the action of hydraulic fluid. Advantage of this approach is more uniform stress distribution across the diaphragm. The further development of this type of pumps is limited by largely unknown mechanical behavior of diaphragm structure, uninvestig...

  9. Sodium test of the Super-Phenix full size primary pump shaft on the CPV-1 test rig at ENEA-Brasimone

    International Nuclear Information System (INIS)

    Tests aimed to verify Super Phenix primary pump rotating assembly behaviour in normal and accidental operating conditions. The tests were conducted on a CPV-1 loop reproducing the operating conditions (sodium-temperature and level, shaft inclination, etc...): thermal tests, hydrostatic bearing and bending velocity measures, endurance tests on the rotating assembly, rig dynamic behaviour, seismic tests

  10. Cryogenic Subsystem to Provide for Nominal Operation and Fast Regeneration of the ITER Primary Cryo-sorption Vacuum Pumps

    International Nuclear Information System (INIS)

    The ITER cryogenic system includes provision for cooling the eight cryo-sorption pumps that maintain vacuum conditions within the tokamak plasma vacuum vessel. The eight pumps are operated such that at any given instant four pumps pump the plasma vessel and four pumps are undergoing four sequential stages of regeneration, each having a duration of 150 s. The regeneration includes a cold helium exhaust stage, warm-up from 4.5 K to 80-100 K, desorption and pump-out of released gases and cool-down from 80-100 K to 4.5 K. Thus after every 150 s of operation one of the four pumps is taken off-line for regeneration and another just-regenerated pump is restored to the set of four pumps that provide the nominal pumping.This paper presents the current design status of the cryogenic subsystems for cooling and heating the cryopumps during pumping and fast regeneration and details of the fluid-dynamic numerical analysis of the cryopumps (Vincenta code) used to study the transient behaviour of helium flow in the cryo-sorption panels during regeneration

  11. Atomistic study of a nanometer-scale pump based on the thermal ratchet concept

    DEFF Research Database (Denmark)

    Oyarzua, Elton; Walther, J. H.; Zambrano, Harvey

    In this study, a novel concept of nanoscale pump fabricated using Carbon Nanotubes (CNTs) is presented. The development of nanofluidic systems provides unprecedented possibilities for the control of biology and chemistry at the molecular level with potential applications in low energy cost devices...... dynamics simulations, we explore the possibility to design thermophoretic pumping devices fabricated of CNTs for water transport in nanoconduits. The design of the nanopumps is based on the concept of the Feynman-Smoluchowski ratchet....

  12. Thermodynamic and Kinetic Investigation of a Chemical Reaction-Based Miniature Heat Pump

    OpenAIRE

    Flueckiger, Scott M.; Volle, Fabien; Garimella, S V; Mongia, Rajiv K.

    2012-01-01

    Representative reversible endothermic chemical reactions (paraldehyde depolymerization and 2-proponal dehydrogenation) are theoretically assessed for their use in a chemical heat pump design for compact thermal management applications. Equilibrium and dynamic simulations are undertaken to explore the operation of the heat pump which upgrades waste heat from near room temperature by approximately 20 in a minimized system volume. A model is developed based on system mass and energy balances cou...

  13. Model based fault diagnosis in a centrifugal pump application using structural analysis

    DEFF Research Database (Denmark)

    Kallesøe, C. S.; Izadi-Zamanabadi, Roozbeh; Rasmussen, Henrik;

    2004-01-01

    A model based approach for fault detection and isolation in a centrifugal pump is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, Analytical Redundant Relations (ARR) and observer designs. Structural considerations on the system are used...... to an industrial benchmark. The benchmark tests have shown that the algorithm is capable of detection and isolation of five different faults in the mechanical and hydraulic parts of the pump....

  14. Model Based Fault Diagnosis in a Centrifugal Pump Application using Structural Analysis

    DEFF Research Database (Denmark)

    Kallesøe, C. S.; Izadi-Zamanabadi, Roozbeh; Rasmussen, Henrik;

    2004-01-01

    A model based approach for fault detection and isolation in a centrifugal pump is proposed in this paper. The fault detection algorithm is derived using a combination of structural analysis, Analytical Redundant Relations (ARR) and observer designs. Structural considerations on the system are used...... to an industrial benchmark. The benchmark tests have shown that the algorithm is capable of detection and isolation of five different faults in the mechanical and hydraulic parts of the pump....

  15. Characterization of the ATP synthase of Propionigenium modestum as a primary sodium pump

    International Nuclear Information System (INIS)

    The ATP synthase (F1F0) of Propionigenium modestum has been purified to a specific ATPase activity of 5.5 units/mg of protein, which is about 6 times higher than that of the bacterial membranes. Analysis by SDS gel electrophoresis indicated that in addition to the five subunits of the F1 ATPase, subunits of Mr 26,000 (a), 23,000 (b), and 7,500 (c) have been purified. The ATPase activity of F1F0 was specifically activated about 10-fold by Na+ ions. The enzyme was strongly inhibited by dicyclohexylcarbodiimide, venturicidin, tributyltin chloride, and azide. After incubation with [14C]dicyclohexylcarbodiimide, about 3-4 mol of the inhibitor was bound per 500,000 g of the enzyme. The radioactive label was specifically bound to subunit c. These subunits form stable aggregates which resist dissociation by SDS at 100 degree C. The monomer is formed upon heating with SDS to 121 degree C or by extraction of the membranes with chloroform/methanol. The ATP synthase was incorporated into liposomes by a freeze-thaw-sonication procedure. The reconstituted proteoliposomes catalyzed the transport of Na+ ions upon ATP hydrolysis. The transport was completely abolished by dicyclohexylcarbodiimide. Whereas monensin prevented the accumulation of Na+ ions, the uptake rate was stimulated 4-5-fold in the presence of valinomycin or carbonyl cyanide m-chlorophenylhydrazone. These results indicate an electrogenic Na+ transport and also that it is a primary event and not accomplished by a H+-translocating ATP synthase in combination with a Na+/H+ antiporter

  16. Modeling and computational simulation of adsorption based chemical heat pumps

    International Nuclear Information System (INIS)

    In this study a methodology is developed for the design of a packed bed reactor to be used in a Chemical Heat Pump (CHP). Adsorption and desorption of ethanol on active carbon packing in the reactor are investigated. Depending on the cycle, i.e. adsorption or desorption, cooling or heating of the reactor material is modeled through transient energy equation. The parameters associated with the vapor-carbon adsorption kinetics are experimentally determined. Then spatial distribution of temperature and adsorbed vapor amount are obtained with respect to time in adsorption–desorption cycles. These profiles are used to predict heating or cooling powers and COP for different adsorbent bed geometries and adsorption/desorption cycle times. Strong effect of heat transfer resistance of the packing, hence reactor size, on the system performance is observed. - Highlights: ► Performance of a chemical pump reactor is investigated theoretically. ► Ethanol adsorption/desorption on active carbon packing is modeled and simulated. ► Adsorption/desorption kinetics and equilibrium relations are found experimentally.

  17. Remaining useful life prediction based on the Wiener process for an aviation axial piston pump

    Institute of Scientific and Technical Information of China (English)

    Wang Xingjian; Lin Siru; Wang Shaoping; He Zhaomin; Zhang Chao

    2016-01-01

    An aviation hydraulic axial piston pump’s degradation from comprehensive wear is a typical gradual failure model. Accurate wear prediction is difficult as random and uncertain char-acteristics must be factored into the estimation. The internal wear status of the axial piston pump is characterized by the return oil flow based on fault mechanism analysis of the main frictional pairs in the pump. The performance degradation model is described by the Wiener process to predict the remaining useful life (RUL) of the pump. Maximum likelihood estimation (MLE) is performed by utilizing the expectation maximization (EM) algorithm to estimate the initial parameters of the Wiener process while recursive estimation is conducted utilizing the Kalman filter method to estimate the drift coefficient of the Wiener process. The RUL of the pump is then calculated accord-ing to the performance degradation model based on the Wiener process. Experimental results indi-cate that the return oil flow is a suitable characteristic for reflecting the internal wear status of the axial piston pump, and thus the Wiener process-based method may effectively predicate the RUL of the pump.

  18. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Ramos, Jose [Departamento de Electronica, Universidad de Malaga, Complejo Tecnologico de Teatinos (2.2.39), 29071 Malaga (Spain); Narvarte-Fernandez, Luis; Poza-Saura, Fernando [Instituto de Energia Solar, Universidad Politecnica de Madrid (IES-UPM), Avenida Complutense s/n (204), 28040 Madrid (Spain)

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  19. The Association between Bile Salt Export Pump Single-Nucleotide Polymorphisms and Primary Biliary Cirrhosis Susceptibility and Ursodeoxycholic Acid Response

    Directory of Open Access Journals (Sweden)

    Rui-rui Chen

    2014-01-01

    Full Text Available Background. Primary biliary cirrhosis (PBC is a chronic and progressive cholestasis liver disease. Bile salt export pump (BSEP is the predominant bile salt efflux system of hepatocytes. BSEP gene has been attached great importance in the susceptibility of PBC and the response rate of ursodeoxycholic acid (UDCA treatment of PBC patients. Methods. In this study, TaqMan assay was used to genotype four variants of BSEP, and the Barcelona criteria were used for evaluating the response rate of UDCA treatment. Results. Variant A allele of BSEP rs473351 (dominant model, OR = 2.063; 95% CI, 1.254–3.393; P=0.004 was highly associated with PBC susceptibility. On the contrary, variant A allele of BSEP rs2287618 (dominant model, OR = 0.617; 95% CI, 0.411–0.928; P=0.020 provided a protective role and Barcelona evaluation criterion indicated that the frequency of variant allele at BSEP rs2287618 was significantly decreased in UDCA-responsive PBC patients (P=0.021. Conclusion. These results suggested that BSEP rs473351 was closely associated with the susceptibility of PBC and if people with BSEP rs2287618 were diagnosed as PBC, the UDCA treatment was not satisfactory. Larger studies with mixed ethnicity subjects and stratified by clinical and subclinical characteristics are needed to validate our findings.

  20. Language-Based Reasoning in Primary Science

    Science.gov (United States)

    Hackling, Mark; Sherriff, Barbara

    2015-01-01

    Language is critical in the mediation of scientific reasoning, higher-order thinking and the development of scientific literacy. This study investigated how an exemplary primary science teacher scaffolds and supports students' reasoning during a Year 4 materials unit. Lessons captured on video, teacher and student interviews and micro-ethnographic…

  1. Pump impeller

    International Nuclear Information System (INIS)

    A mixed-flow pump impeller, which may be used, for example, as a primary pump for circulating sodium as the primary coolant in a fast nuclear reactor, is described which comprises an impeller with evenly-spaced blades. Some of the blades, which are symmetrically disposed around the axis of rotation of the impeller, extend beyond the ends of the other blades towards the suction side of the pump to form an inducer. The channels defined between the extensions of the extended blades follow helical paths parallel to the axis of rotation. The leading edges of the unextended blades are interposed between the extended blades in the region of divergence of flow from the axis of rotation. The provision of the inducer reduces the risk of cavitation in the pump, which could cause rapid wear of the impeller. A shroud may be provided for the unextended blades. (author)

  2. A membrane-based serpentine-shape pneumatic micropump with pumping performance modulated by fluidic resistance

    International Nuclear Information System (INIS)

    This paper reports a new membrane-based pneumatic micropump with new serpentine-shape (S-shape) pneumatic channels intended for achieving high-throughput pumping in a microfluidic system at a relatively low pumping rate and a board flow rate range. The key feature of this design is the ability to modulate the pumping rates by fine-tuning the fluidic resistance of injected compressed air in the designed pneumatic microchannels and the chambers of the micropump. In the study, several S-shape pneumatic micropumps with various layouts were designed and fabricated based on thick-film photoresist lithography and polydimethylsiloxane (PDMS) replication processes. To investigate designs with a suitable pumping performance, S-shape pneumatic micropumps with varied lengths (1000, 5000 and 10 000 µm), varied widths (20, 40 and 200 µm) of the pneumatic microchannel bridging two rectangular pneumatic chambers, and different numbers of pneumatic channel bends (two and four U-shape bends) were designed and evaluated experimentally by using high-speed CCD-coupled microscopic observation of the movement of PDMS membrane pulsation and pumping rate measurements. The results revealed that under the experimental conditions studied, the layout of the S-shape pneumatic micropump with three rectangular pneumatic chambers, 5000 µm long and 40 µm wide pneumatic microchannel and four U-shape bends in the pneumatic microchannel was found to be capable of providing a broader pumping rate range from 0 to 539 µl h−1 compared to the other designs. As a whole, the experimental results demonstrate the use of fluidic resistance of injected air in a pneumatic micropump with S-shape layout to control its pumping performance, which largely expands the flexibility of its pumping application in a microfluidic system

  3. Fault Detection And Diagnosis For Air Conditioners And Heat Pumps Based On Virtual Sensors

    OpenAIRE

    Kim, Woohyun

    2013-01-01

    The primary goal of this research is to develop and demonstrate an integrated, on-line performance monitoring and diagnostic system with low cost sensors for air conditioning and heat pump equipment. Automated fault detection and diagnostics (FDD) has the potential for improving energy efficiency along with reducing service costs and comfort complaints. To achieve this goal, virtual sensors with low cost measurements and simple models were developed to estimate quantities that would be expens...

  4. Numerical Investigation and Optimization of SBS-Based Slow-Light Using Filtered Incoherent Pump

    International Nuclear Information System (INIS)

    The performance of stimulated Brillouin scattering (SBS)-based slow light using a novel spectrally-sliced broadband incoherent pump source is numerically studied. The profile of the pump-power spectrum is determined by the transmission spectra of the optical filter followed by the polarized broadband incoherent pump source. We also investigate the performance of Gaussian-type and super-Gaussian-type filtering under different spectrally-sliced bandwidths and pump power levels for 2.5 Gbit/s return-to-zero pulse (50% duty-cycle). The pulse broadening is characterized by the full width of half maximum (FWHM) and the rms pulse width, respectively. However, the results obtained by the two kinds of measurement methods deviate from each other with increasing pump power. Compared with the regular Gaussian-type filtering, the pulse broadening can be significantly reduced using super-Gaussian-type filtering at the cost of a small reduction in delay time. Furthermore, the maximum improvement in pulse broadening of ΔBFWHM = 28.4% and λBRMS = 10.4% is achieved by using a five-order super-Gaussian-type filter and a pump power of 500 mW

  5. NOISE IDENTIFICATION FOR HYDRAULIC AXIAL PISTON PUMP BASED ON ARTIFICIAL NEURAL NETWORKS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The noise identification model of the neural networks is established for the 63SCY14-1B hydraulic axial piston pump. Taking four kinds of different port plates as instances, the noise identification is successfully carried out for hydraulic axial piston pump based on experiments with the MATLAB and the toolbox of neural networks. The operating pressure, the flow rate of hydraulic axial piston pump, the temperature of hydraulic oil, and bulk modulus of hydraulic oil are the main parameters having influences on the noise of hydraulic axial piston pump. These four parameters are used as inputs of neural networks, and experimental data of the noise are used as outputs of neural networks. Error of noise identification is less than 1% after the neural networks have been trained. The results show that the noise identification of hydraulic axial piston pump is feasible and reliable by using artificial neural networks. The method of noise identification with neural networks is also creative one of noise theoretical research for hydraulic axial piston pump.

  6. Numerical Investigation and Optimization of SBS-Based Slow-Light Using Filtered Incoherent Pump

    Institute of Scientific and Technical Information of China (English)

    ZHENG Di; PAN Wei; YAN Lian-Shan; LUO Bin; ZOU Xi-Hua; WEN Kun-Hua; JIANG Ning

    2009-01-01

    The performance of stimulated Brillouin scattering(SBS)-based slow light using a novel spectrally-sliced broad band incoherent pump source is numerically studied.The profile of the pump-power spectrum is determined by the transmission spectra of the optical filter followed by the polarized broadband incoherent pump source.We also investigate the performance of Gaussian-type and super-Gaussian-type filtering under different spectrally-sliced bandwidths and pump power levels for 2.5 Gbit/s return-to-zero pulse(50% duty-cycle).The pulse broadening is characterized by the full width of half maximum(FWHM)and the rms pulse width,respectively.However,the results obtained by the two kinds of measurement methods deviate from each other with increasing pump power.Compared with the regular Gaussian-type filtering,the pulse broadening can be significantly reduced using super-Gaussian-type filtering at the cost of a small reduction in delay time.Furthermore,the maximum improvement in pulse broadening of △B_(FWHM) = 28.4% and △B_(RMS)= 10.4% is achieved by using a five-order super-Gaussian-type filter and a pump power of 500mw.

  7. A Subfemtotesla Atomic Magnetometer Based on Hybrid Optical Pumping of Potassium and Rubidium

    Science.gov (United States)

    Li, Yang; Cai, Hongwei; Ding, Ming; Quan, Wei; Fang, Jiancheng

    2016-05-01

    Atomic magnetometers, based on detection of Larmor spin precession of optically pumped atoms, have been researched and applied extensively. Higher sensitivity and spatial resolution combined with no cryogenic cooling of atomic magnetometers would enable many applications with low cost, including the magnetoencephalography (MEG). Ultrahigh sensitivity atomic magnetometer is considered to be the main development direction for the future. Hybrid optical pumping has been proposed to improve the efficiency of nuclear polarization. But it can also be used for magnetic field measurement. This method can control absorption of optical pumping light, which is benefit for improving the uniformity of alkali metal atoms polarization and the sensitivity of atomic magnetometer. In addition, it allows optical pumping in the absence of quenching gas. We conduct experiments with a hybrid optically pumped atomic magnetometer using a cell containing potassium and rubidium. By adjusting the density ratio of alkali metal and the pumping laser conditions, we measured the magnetic field sensitivity better than 0.7 fT/sqrt(Hz).

  8. EXERGY-BASED ECOLOGICAL ANALYSIS OF GENERALIZED IRREVERSIBLE HEAT PUMP SYSTEM

    Directory of Open Access Journals (Sweden)

    GOVIND MAHESHWARI

    2011-10-01

    Full Text Available A reverse Carnot cycle forms the basis of all heat-pump cycles in providing heating and cooling loads. The optimal exergy-based Ecological analysis of an irreversible Heat-pump system with the losses of heat resistance, heat leak and internal irreversibility has been carried out by taking into account Exergy based ecological function (E as an objective in the viewpoint of Finite-Time-Thermodynamics (FTT or Entropy Generation Minimization (EGM. Exergy is defined here as the power required minus the lost power. The effects of irreversibilities along with internal heat leakage on coefficient on the performance of the system are investigated. The exergy based Ecological function decreases steadily with irreversibilites and heat leakages in the system. COP in such a system increases with the cycle temperature ratio. If a heat pump cycle is optimized with above mentioned criterion, there is a trade-off between its coefficient of Performance and the heating load it provides.

  9. Heat pump-based geothermal energy. Technical and economic study. The costs of heat-pump-based geothermal energy

    International Nuclear Information System (INIS)

    This study aims at identifying the financial basis on which actors of a geothermal project for heating, cooling and hot water production can rely. It also aims at describing the three main technical solutions for very-low-energy geothermal: horizontal sensors, vertical probes, and geothermal doublets on aquifer. After a presentation of the adopted methodology and of the different economic, thermal and technical hypotheses, the respective costs of these technical solutions are assessed and a comparison between these systems and conventional energies is reported. The economic study is performed for different markets: individual housing, collective housing, and office building. Different aspects of each operation are studied: underground works (drilling) and surface equipment (heat pump and support). Investment, maintenance and operational costs are analysed

  10. Improvement of four-wave mixing-based wavelength conversion efficiency in dispersion shifted fiber by 40-GHz clock pumping

    Institute of Scientific and Technical Information of China (English)

    Aiying Yang; Yunan Sun

    2008-01-01

    @@ 40-GHz clock modulated signal as a pump to improve the efficiency of four-wave mixing (FWM)-based wavelength conversion in a 26.5-km dispersion shifted fiber (DSF) is investigated. The experimental results demonstrate that the conjugated FWM component has higher intensity with the clock pumping than that with the continuous-wave (CW) light pumping. The improvement of FWM-based wavelength conversion efficiency is negligible when the pump power is less than Brillouin threshold. But when the pump power is greater than Brillouin threshold, the improvement becomes significant and increases with the increment of pump power. The improvement can increase up to 9 dB if pump power reaches 17 dBm.

  11. Methodology to monitor and diagnostic vibrations of the motor-pumps used in the primary cooling system of IEAR-1 nuclear research reactor

    International Nuclear Information System (INIS)

    The objectives of this study are to establish a strategy to monitor and diagnose vibrations of the motor pumps used in the primary reactor cooling system of the IEA-R1 nuclear research reactor, to verify the possibility of using the existing installed monitoring vibration system and to implement such strategy in a continuous way. Four types of mechanical problems were considered: unbalancing, misalignment, gaps and faults in bearings. An adequate set of analysis tools, well established by the industry, was selected. These are: global measurements of vibration, velocity spectrum and acceleration envelope spectrum. Three sources of data and information were used; the data measured from the primary pumps, experimental results obtained with a Spectra Quest machine used to simulate mechanical defects and data from the literature. The results show that, for the specific case of the motor-pumps of IEA-R1 nuclear research reactor, although the technique using the envelope of acceleration, which is not available in the current system used to monitor the vibration of the motor pumps, is the one with best performance, the other techniques available in the system are sufficient to monitor the four types of mechanical problems mentioned. The proposed strategy is shown and detailed in this work. (author)

  12. A new heating system based on coupled air source absorption heat pump for cold regions: Energy saving analysis

    International Nuclear Information System (INIS)

    Highlights: • A double-stage coupled air source absorption heat pump (ASAHP) is proposed. • The coupled ASAHP exhibits stable and high performance in very cold regions. • Energy-saving rate of the coupled ASAHP in all the typical cities is above 20%. - Abstract: Energy consumption for heating and domestic hot water is very high. The heating system based on an air source absorption heat pump (ASAHP) had been assessed to have great energy saving potential. However, the single-stage ASAHP exhibits poor performance when the outdoor air temperature is very low. A double-stage coupled ASAHP is proposed to improve the energy-saving potential of single-stage ASAHP in cold regions. The heating capacity and primary energy efficiency (PEE) of the proposed system operated in both coupled mode and single-stage mode are simulated under various working conditions. The building load and primary energy consumption of different heating systems applied in cold regions are analyzed comparatively to investigate the energy-saving potential of the coupled ASAHP. Results show that the coupled ASAHP exhibits stable PEE and provides high heating capacity in very cold conditions. The energy-saving rate of the coupled ASAHP in all the typical cities is above 20%. In addition, the energy-saving potential of the single-stage ASAHP in severely cold areas can be improved obviously by coupled ASAHP, with an improvement of 7.73% in Harbin

  13. New inverse method of centrifugal pump blade based on free form deformation

    International Nuclear Information System (INIS)

    In this research, a new inverse method for centrifugal pump blade based on free form deformation is proposed, the free form deformation is used to parametric the pump blade. The blade is implanted to a trivariate control volume which is equally subdivided by control lattice. The control volume can be deformed by moving the control lattice, thereupon the object is deformed. The flow in pump is solved by using a three dimensional turbulent model. The lattice deformation function is constructed according to the gradient distribution of fluid energy along the blade and its objective distribution. Deform the blade shape continually according to the flow solve, and we can get the objective blade shape. The calculation case shows that the proposed inverse method based on FFD method is rational

  14. Cavitation performance prediction of mixed-flow pump based on CFD

    International Nuclear Information System (INIS)

    The computational fluid dynamics (CFD) method is used to investigate the three-dimensional cavitation flow fields in a mixed-flow pump with high specific speed. In the numerical modeling, the homogeneous mixture model and Navier-Stokes equation with RNG k−ε turbulence model are employed. At the best efficiency condition, the cavitation location on the impeller blades and the distribution situation of vapor volume fraction were analyzed, as well as the performance curve between the pump's NPSHA and efficiency were predicted. The results show that, the cavitation directly affects the pressure distribution on impeller blade surfaces, and also results in change of the pump external characteristic. Under the primary cavitation condition, Water vapors first accumulate on the suction surface of blade's leading edge, which is close to the tip. With the decrease of inlet total pressure, the cavitation region extended towards the trailing edge and water vapor fraction volume become larger gradually. When cavitation is serious, water vapors mainly accumulate on the suction surface of blade's trailing edge. The prediction curve has the same trend as the practical curve, which can reveal the mixed-flow pump cavitation within the static characteristics.

  15. Optimization design of recuperator in a chemical heat pump system based on entransy dissipation theory

    International Nuclear Information System (INIS)

    Based on the entransy dissipation theory, the multi-parameter optimization design of recuperator is conducted in an Isopropanol–Acetone–Hydrogen (IAH) chemical heat pump system. The performance of the heat pump system can be improved significantly through the multi-parameter optimization, when the main operation parameters of chemical heat pump remain unchanged. When the main operation parameters of chemical heat pump and the heat transfer area of recuperator remain unchanged, the heat transfer rate of recuperator, the high-temperature heat released from the exothermic reactor, and the coefficient of performance (COP) and exergy efficiency of IAH heat pump system greatly increase while the compressor power decreases remarkably as entransy dissipation number decreases. This is done only by optimizing the combination of design parameters of recuperator taking entransy dissipation number as the objective function under certain constraint conditions, and the cost is no more than the low-temperature waste heat having no practical value. -- Highlights: ► Optimization of heat exchanger based on entransy dissipation is conducted at system level. ► The optimization approach is very effective at both component and system levels. ► The performance of the system is improved significantly after the optimization design. ► The obtained high-temperature heat is improved greatly at the expense of low-temperature heat.

  16. Combined loss of primary and secondary coolant AC pump power design-basis event for the K-reactor safety analysis report

    International Nuclear Information System (INIS)

    The combined loss of alternating-current (ac) power to the primary coolant and secondary coolant system pumps has been included as a design-basis event in Chap. 15 of the safety analysis report for the K reactor at the U.S. Department of Energy's Savannah River site (SRS) nuclear materials production complex near Aiken, South Carolina. This event can arise from a disruption of the entire 115-kV SRS power grid or a lesser disturbance affecting the K-reactor area, combined with a failure of the standby emergency power sources. The first scenario is referred to as a open-quotes station blackout,close quotes and the second scenario is designated as a open-quotes mini-blackout.close quotes This is a condition-11 event (incident of moderate frequency) per the criterion (frequency of occurrence ≥ 1 x 10-6 per year) for credible eventualities in the design-basis envelope. The event causes the primary coolant flow to drop and stabilize at ∼27% of its full level (5.83 + 05 ell/min). Likewise, the secondary coolant flow drops and settles also at ∼27% of its full level (6.36 x 105 ell/min). The final primary coolant flow is maintained by the reduced pumping provided by diesel powered direct-current motors. The final secondary coolant flow is driven by gravity from the height differential between the supply and discharge basins. Both flows coast down gradually due to the action of flywheels in all of the six primary coolant pumps and in two of the ten secondary coolant pumps

  17. Heat pumps and the economy. Part 1. Primary energy consumption in houses; Warmtepompen en economie. Deel 1. Primair energiegebruik in woningen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-09-01

    In a positioning paper of the NL Agency the economic perspective of heat pumps is outlined. In three parts the chapters of the paper are summarized. This first part focuses on primary energy consumption in Dutch houses [Dutch] In een positioning paper van het Agentschap NL wordt het economisch perspectief van warmtepompen belicht. In 3 delen wordt steeds 1 hoofdstuk uit deze paper samengevat. Dit eerste deel gaat in op primair energiegebruik in Nederlandse woningen.

  18. A comparison of diesel, biodiesel and solar PV-based water pumping systems in the context of rural Nepal

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Pokharel, Govind Raj; Østergaard, Poul Alberg

    2014-01-01

    using petro-diesel, jatropha-based biodiesel and solar photovoltaic pumps. The technical system design consists of system sizing of prime mover (engine, solar panel and pumps) and estimation of reservoir capacity, which are based on the annual aggregate water demand modelling. With these investigations...... area, the levelised cost of pumping 1 L of water is higher than that of a solar pump and even higher when compared with diesel, if the seed yield per plant is less than 2 kg and without subsidy on the investment cost of cultivation and processing. With the productivity of 2.5 kg/plant, a biodiesel...... rural end-uses. In this context, this article is prepared to investigate energy alternatives to pump drinking water in one of the remote rural village of Nepal, which has no means of running water source. Analyses in this article are based on the formulation of three technical scenarios of water pumping...

  19. Wireless implantable chip with integrated nitinol-based pump for radio-controlled local drug delivery.

    Science.gov (United States)

    Fong, Jeffrey; Xiao, Zhiming; Takahata, Kenichi

    2015-02-21

    We demonstrate an active, implantable drug delivery device embedded with a microfluidic pump that is driven by a radio-controlled actuator for temporal drug delivery. The polyimide-packaged 10 × 10 × 2 mm(3) chip contains a micromachined pump chamber and check valves of Parylene C to force the release of the drug from a 76 μL reservoir by wirelessly activating the actuator using external radio-frequency (RF) electromagnetic fields. The rectangular-shaped spiral-coil actuator based on nitinol, a biocompatible shape-memory alloy, is developed to perform cantilever-like actuation for pumping operation. The nitinol-coil actuator itself forms a passive 185 MHz resonant circuit that serves as a self-heat source activated via RF power transfer to enable frequency-selective actuation and pumping. Experimental wireless operation of fabricated prototypes shows successful release of test agents from the devices placed in liquid and excited by radiating tuned RF fields with an output power of 1.1 W. These tests reveal a single release volume of 219 nL, suggesting a device's capacity of ~350 individual ejections of drug from its reservoir. The thermal behavior of the activated device is also reported in detail. This proof-of-concept prototype validates the effectiveness of wireless RF pumping for fully controlled, long-lasting drug delivery, a key step towards enabling patient-tailored, targeted local drug delivery through highly miniaturized implants. PMID:25473933

  20. Controlling a Conventional LS-pump based on Electrically Measured LS-pressure

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    for being able to generate a hydraulic pilot pressure. In this paper controlling a hydraulic variable pump is considered. The LS-pressure is measured electrically and the hydraulic pilot pressure is generated using a small spool valve. From a control point of view there are two approaches for controlling...... this system, by either generating a copy of the LS-pressure, the LS-pressure being the output, or letting the output be the pump pressure. The focus of the current paper is on the controller design based on the first approach. Specifically a controlled leakage flow is used to avoid the need for a switching...

  1. A real option-based simulation model to evaluate investments in pump storage plants

    International Nuclear Information System (INIS)

    Investments in pump storage plants are expected to grow especially due to their ability to store an excess of supply from wind power plants. In order to evaluate these investments correctly the peculiarities of pump storage plants and the characteristics of liberalized power markets have to be considered. The main characteristics of power markets are the strong power price volatility and the occurrence of prices spikes. In this article a valuation model is developed capturing these aspects using power price simulation, optimization of unit commitment and capital market theory. This valuation model is able to value a future price-based unit commitment planning that corresponds to future scope of actions also called real options. The resulting real option value for the pump storage plant is compared with the traditional net present value approach. Because this approach is not able to evaluate scope of actions correctly it results in strongly smaller investment values and forces wrong investment decisions. (author)

  2. Impellers of low specific speed centrifugal pump based on the draughting technology

    International Nuclear Information System (INIS)

    The authors analyzed the reasons of low efficiency under different operation condition based on the performance test and CFD numerical simulation approach. And the analysis focuses on the relationship between pump efficiency and inner flow characteristics. In order to improve the internal flow and increase efficiency of the pump, some draughting methods of improving the internal flow structure have been proposed, and some new impellers were developed by these methods. The main geometric parameters of the impellers, such as diameter, width and installation of the size, were consistent with the original impeller. The experimental results show that the efficiency of new impellers was improved significantly. The authors' work has opened up a new direction for further improving the efficiency of the low specific speed centrifugal pump.

  3. A case-based reasoning approach for estimating the costs of pump station projects

    Directory of Open Access Journals (Sweden)

    Mohamed M. Marzouk

    2011-10-01

    Full Text Available The effective estimation of costs is crucial to the success of construction projects. Cost estimates are used to evaluate, approve and/or fund projects. Organizations use some form of classification system to identify the various types of estimates that may be prepared during the lifecycle of a project. This research presents a parametric-cost model for pump station projects. Fourteen factors have been identified as important to the influence of the cost of pump station projects. A data set that consists of forty-four pump station projects (fifteen water and twenty-nine waste water are collected to build a Case-Based Reasoning (CBR library and to test its performance. The results obtained from the CBR tool are processed and adopted to improve the accuracy of the results. A numerical example is presented to demonstrate the development of the effectiveness of the tool.

  4. A real option-based simulation model to evaluate investments in pump storage plants

    International Nuclear Information System (INIS)

    Investments in pump storage plants are expected to grow especially due to their ability to store an excess of supply from wind power plants. In order to evaluate these investments correctly the peculiarities of pump storage plants and the characteristics of liberalized power markets have to be considered. The main characteristics of power markets are the strong power price volatility and the occurrence of prices spikes. In this article a valuation model is developed capturing these aspects using power price simulation, optimization of unit commitment and capital market theory. This valuation model is able to value a future price-based unit commitment planning that corresponds to future scope of actions also called real options. The resulting real option value for the pump storage plant is compared with the traditional net present value approach. Because this approach is not able to evaluate scope of actions correctly it results in strongly smaller investment values and forces wrong investment decisions.

  5. Direct electro-optical pumping for hybrid CdSe nanocrystal/III-nitride based nano-light-emitting diodes

    Science.gov (United States)

    Mikulics, M.; Arango, Y. C.; Winden, A.; Adam, R.; Hardtdegen, A.; Grützmacher, D.; Plinski, E.; Gregušová, D.; Novák, J.; Kordoš, P.; Moonshiram, A.; Marso, M.; Sofer, Z.; Lüth, H.; Hardtdegen, H.

    2016-02-01

    We propose a device concept for a hybrid nanocrystal/III-nitride based nano-LED. Our approach is based on the direct electro-optical pumping of nanocrystals (secondary excitation) by electrically driven InGaN/GaN nano-LEDs as the primary excitation source. To this end, a universal hybrid optoelectronic platform was developed for a large range of optically active nano- and mesoscopic structures. The advantage of the approach is that the emission of the nanocrystals can be electrically induced without the need of contacting them. The proof of principal was demonstrated for the electro-optical pumping of CdSe nanocrystals. The nano-LEDs with a diameter of 100 nm exhibit a very low current of ˜8 nA at 5 V bias which is several orders of magnitude smaller than for those conventionally used. The leakage currents in the device layout were typically in the range of 8 pA to 20 pA/cm2 at 5 V bias. The photon-photon down conversion efficiency was determined to be 27%. Microphotoluminescence and microelectroluminescence characterization demonstrate the potential for future optoelectronics and highly secure "green" information technology applications.

  6. Combinatorial Optimization Method for Operation of Pumping Station with Adjustable Blade and Variable Speed Based on Experimental Optimization of Subsystem

    OpenAIRE

    Yi Gong; Jilin Cheng

    2014-01-01

    A decomposition-dynamic programming aggregation method based on experimental optimization for subsystem was proposed to solve mathematical model of optimal operation for single pumping station with adjustable blade and variable speed. Taking minimal daily electric cost as objective function and water quantity pumped by units as coordinated variable, this model was decomposed into several submodels of daily optimal operation with adjustable blade and variable speed for single pump unit which w...

  7. Development of optical sensing system for detection of Fe ions using conductive polymer actuator based microfluidic pump

    OpenAIRE

    Kim, Jung Ho; Lau, King-Tong; Fay, Cormac; Diamond, Dermot

    2008-01-01

    In this paper, we present a novel microfluidic optical sensing system by combining a low-power conductive polymer -based microfluidic pump and a microfluidic chip integrated with an optical sensor. A self priming microfluidic pump is developed using a polypyrrole. A microfluidic chip- optical detector module that contained an optical cuvette with LED and photo-diode optical sensing module was fabricated. Integration of the micro pump and the microfluidic chips complete...

  8. Directly diode-pumped femtosecond laser based on an Yb:KYW crystal

    Science.gov (United States)

    Kim, G. H.; Yang, J.; Lee, D. S.; Kulik, A. V.; Sall', E. G.; Chizhov, S. A.; Yashin, V. E.; Kang, U.

    2012-01-01

    Ultrashort pulse laser systems are widely used in many areas such as microprocessing of various materials, the generation of terahertz radiation, nonlinear optics, medical tomography, chemistry, and biology due to the high peak power and large spectral width. For a practical usage of the femtosecond lasers, they must be fairly compact and stable. These conditions are most fully met when laser media are used that allow direct pumping with the radiation from semiconductor injection lasers, which are more compact, reliable, and inexpensive than pumping with solid-state lasers. Since Ytterbium-doped crystals have a broad luminescence band for generating femtosecond pulses less than 500 fs wide, they are attractive as materials for lasers with direct diode pumping. Moreover, the position of the central luminescence wavelength of Yb:KGW and Yb:KYW crystals makes them promising priming sources of femtosecond pulses for amplifiers that operate at wavelengths close to 1 μm (Yb:KGW, Yb-glass, Nd-glass, Yb:YAG, etc.) We developed a femtosecond generator based on the Yb:KYW crystal with direct pumping by the radiation of a laser diode with fiber output of the pump radiation. The use of such pumping, as well as of chirped mirrors to compensate intracavity dispersion, made it possible to generate a continuous sequence of optical pulses 90 fs wide at a frequency of 87.8 MHz with a mean radiation power of more than 1 W. The product of the pulse width by the spectral width is close to the theoretical limit, and this indicates that there is no frequency modulation.

  9. RESEARCH OF INNER FLOW IN A DOUBLE BLADES PUMP BASED ON OPENFOAM

    Institute of Scientific and Technical Information of China (English)

    LIU Hou-lin; REN Yun; WANG Kai; WU Deng-hao; RU Wei-min; TAN Ming-gao

    2012-01-01

    The inner flow analysis of centrifugal pumps has gradually become an important issue for the hydraulic design and performance improvement.Nowadays,CFD simulation toolbox of pump inner flow mainly contains commercial tools and open source tools.There are some detects for commercial CFD software for the numerical simulation of 3-D turbulent internal flow in pump,especially in capturing the flow characteristics under the off-design operating conditions.Additionally,it is difficult for researchers to do further investigation because of the undeclared source.Therefore,an open source software like Open Field Operation and Manipulation (OpenFOAM) is increasingly popular with researchers from all over the world.In this paper,a new computational study was implemented based on the original solver and was used to directly simulate the steady-state inner flow in a double blades pump,with the specific speed is 111.In order to disclose the characteristics deeply,three research schemes were conducted.The ratios (Q/Qd) of the flow rate are 0.8,1.0 and 1.2,respectively.The simulation results were verified with the Particle Imaging Velocimetry (PIV) experimental results,and the numerical calculation results agree well with the experimental data.Meanwhile,the phenomena of flow separation under the off-design operating conditions are well captured by OpenFOAM.The results indicate that OpenFOAM possesses obvious strong predominance in computing the internal flow field of pump.The analysis results can also be used as the basis for the further research and the improvement of centrifugal pump.

  10. Characterization of zeolite-based coatings for adsorption heat pumps

    CERN Document Server

    Freni, Angelo; Bonaccorsi, Lucio; Chmielewski, Stefanie; Frazzica, Andrea; Calabrese, Luigi; Restuccia, Giovanni

    2015-01-01

    This book proposes a radically new approach for characterizing thermophysical and mechanical properties of zeolite-based adsorbent coatings for Adsorptive Heat Transformers (AHT). It presents a developed standard protocol for the complete characterization of advanced coated adsorbers. Providing an in-depth analysis of the different procedures necessary for evaluating the performance of adsorbers, it also presents an analysis of their stability under the hydrothermal and mechanical stresses during their entire life cycle. Adsorptive Heat Transformers (AHT), especially adsorption chillers and

  11. Micro pumping methods based on AC electrokinetics and Electrorheologically actuated PDMS valves

    Science.gov (United States)

    Soni, Gaurav; Squires, Todd; Meinhart, Carl

    2006-11-01

    We have developed 2 different micropumping methods for transporting ionic fluids through microchannels. The first method is based on Induced Charge Electroosmosis (ICEO) and AC flow field-effect. We used an AC electric field to produce a symmetric ICEO flow on a planar electrode, called `gate'. In order to break the symmetry of ICEO, we applied an additional AC voltage to the gate electrode. Such modulation of the gate potential is called field effect and produces a unidirectional pumping over the gate surface. We used micro PIV to measure pumping velocities for a range of ionic concentration, AC frequency and gate voltage. We have also conducted numerical simulations to understand the deteriorating effect of lateral conduction of surface charge on the pumping velocities. The second method is based on vibration of a flexible PDMS diaphragm actuated by an electrorheological (ER) fluid. ER fluid is a colloidal suspension exhibiting a reversible liquid-to-solid transition under an electric field. This liquid-to-solid transition can yield very high shear stress and can be used to open and close a PDMS valve. Three such valves were fabricated and actuated in a peristaltic fashion in order to achieve positive displacement pumping of fluids.

  12. Estimation of the Pumping Pressure from Concrete Composition Based on the Identified Tribological Parameters

    Directory of Open Access Journals (Sweden)

    Chanh-Trung Mai

    2014-01-01

    Full Text Available A new method is proposed to estimate pumping pressure based on concrete composition without experimental measurements. Previous studies show that the pumping pressure depends on the interface friction between concrete and the wall of the pumping pipes. This friction is determined by the thickness and the rheology of the boundary layer formed at the interface. The latter is mainly formed by water, cement, and fine sand particles which come from concrete. Hence, interface parameters, which are the viscous constant and the interface yield stress, are directly related to concrete composition. In this work, at the first time the interface yield stress model is suggested and validated thanks to an experimental database also carried out in this study with a precision of around 13%. Then, the pressure estimation method is proposed using the two models to calculate the interface parameters. The validation of the method is carried out basing on the comparison with real measurements on the building site. This method enables the calculation of the pumping pressure with a precision of around 15%.

  13. Hydration induced material transfer in membranes of osmotic pump tablets measured by synchrotron radiation based FTIR.

    Science.gov (United States)

    Wu, Li; Yin, Xianzhen; Guo, Zhen; Tong, Yajun; Feng, Jing; York, Peter; Xiao, Tiqiao; Chen, Min; Gu, Jingkai; Zhang, Jiwen

    2016-03-10

    Osmotic pump tablets are reliable oral controlled drug delivery systems based on their semipermeable membrane coating. This research used synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy and imaging to investigate the hydration induced material transfer in the membranes of osmotic pump tablets. SR-FTIR was applied to record and map the chemical information of a micro-region of the membranes, composed of cellulose acetate (CA, as the water insoluble matrix) and polyethylene glycol (PEG, as the soluble pore forming agent and plasticizing agent). The microstructure and chemical change of membranes hydrated for 0, 5, 10 and 30min were measured using SR-FTIR, combined with scanning electronic microscopy and atom force microscopy. The SR-FTIR microspectroscopy results indicated that there was a major change at the absorption range of 2700-3100cm(-1) in the membranes after different periods of hydration time. The absorption bands at 2870-2880cm(-1) and 2950-2960cm(-1) were assigned to represent CA and PEG, respectively. The chemical group signal distribution illustrated by the ratio of PEG to CA demonstrated that the trigger of drug release in the preliminary stage was due to the rapid transfer of PEG into liquid medium with a sharp decrease of PEG in the membranes. The SR-FTIR mapping results have demonstrated the hydration induced material transfer in the membranes of osmotic pump tablets and enabled reassessment of the drug release mechanism of membrane controlled osmotic pump systems. PMID:26802550

  14. Transient Stress- and Strain-Based Hemolysis Estimation in a Simplified Blood Pump

    OpenAIRE

    Pauli, L.; Nam, J.; Pasquali, M.; BEHR, M

    2013-01-01

    We compare two approaches to numerical estimation of mechanical hemolysis in a simplified blood pump model. The stress-based model relies on the instantaneous shear stress in the blood flow, whereas the strain-based model uses an additional tensor equation to relate distortion of red blood cells to a shear stress measure. We use the newly proposed least-squares finite element method (LSFEM) to prevent negative concentration fields and show a stable and volume preserving LSFEM for the tensor e...

  15. Computation of stress distribution in a mixed flow pump based on fluid-structure interaction analysis

    International Nuclear Information System (INIS)

    The internal flow evolution of the pump was induced with impeller movement. In various conditions, the peak load on centrifugal blade under the change of rotational speed or flow rate was also changed. It would cause an error when inertia load with a safety coefficient (that was difficult to ascertain) was applied in structure design. In order to accurately analyze the impeller stress under various conditions and improve the reliability of pump, based on a mixed flow pump model, the stress distribution characteristic was analyzed under different flow rates and rotational speeds. Based on a three-dimensional calculation model including impeller, guide blade, inlet and outlet, the three-dimension incompressible turbulence flow in the centrifugal pump was simulated by using the standard k-epsilon turbulence model. Based on the sequentially coupled simulation approach, a three-dimensional finite element model of impeller was established, and the fluid-structure interaction method of the blade load transfer was discussed. The blades pressure from flow simulation, together with inertia force acting on the blade, was used as the blade loading on solid surface. The Finite Element Method (FEM) was used to calculate the stress distribution of the blade respectively under inertia load, or fluid load, or combined load. The results showed that the blade stress changed with flow rate and rotational speed. In all cases, the maximum stress on the blade appeared on the pressure side near the hub, and the maximum static stress increased with the decreasing of the flow rate and the increasing of rotational speed. There was a big difference on the static stress when inertia load, fluid load and combined loads was applied respectively. In order to more accurately calculate the stress distribution, the structure analysis should be conducted due to combined loads. The results could provide basis for the stress analysis and structure optimization of pump

  16. Computation of stress distribution in a mixed flow pump based on fluid-structure interaction analysis

    Science.gov (United States)

    Hu, F. F.; Chen, T.; Wu, D. Z.; Wang, L. Q.

    2013-12-01

    The internal flow evolution of the pump was induced with impeller movement. In various conditions, the peak load on centrifugal blade under the change of rotational speed or flow rate was also changed. It would cause an error when inertia load with a safety coefficient (that was difficult to ascertain) was applied in structure design. In order to accurately analyze the impeller stress under various conditions and improve the reliability of pump, based on a mixed flow pump model, the stress distribution characteristic was analyzed under different flow rates and rotational speeds. Based on a three-dimensional calculation model including impeller, guide blade, inlet and outlet, the three-dimension incompressible turbulence flow in the centrifugal pump was simulated by using the standard k-epsilon turbulence model. Based on the sequentially coupled simulation approach, a three-dimensional finite element model of impeller was established, and the fluid-structure interaction method of the blade load transfer was discussed. The blades pressure from flow simulation, together with inertia force acting on the blade, was used as the blade loading on solid surface. The Finite Element Method (FEM) was used to calculate the stress distribution of the blade respectively under inertia load, or fluid load, or combined load. The results showed that the blade stress changed with flow rate and rotational speed. In all cases, the maximum stress on the blade appeared on the pressure side near the hub, and the maximum static stress increased with the decreasing of the flow rate and the increasing of rotational speed. There was a big difference on the static stress when inertia load, fluid load and combined loads was applied respectively. In order to more accurately calculate the stress distribution, the structure analysis should be conducted due to combined loads. The results could provide basis for the stress analysis and structure optimization of pump.

  17. Seismic tests in sodium of the SPX-1 primary pump shaft carried out in the CPV-1 test rig at ENEA-Brasimone

    International Nuclear Information System (INIS)

    Dynamic tests were carried out by ISMES, on behalf of ENEA and CEA and in co-operation with FIAT/TTG, on a SPX-1 primary pump shaft. These tests were conducted, mainly in sodium, in the CPV-1 test rig at the ENEA Brasimone Center. The excitation was applied to the flange supporting the hydrostatic bearing. After some preliminary analysis performed in absence of liquid sodium and at ambient temperature, the following tests were performed on the rig filled with sodium at operating temperature: (A) sine sweeps between 1 and 15 Hz, (B) ambient vibration investigation, and (C) seismic tests with a SSE acceleration time-history (20 s duration) calculated by CEA at hydrostatic bearing level. Two sets of seismic tests were carried out, each time increasing amplitudes up to 70% of SSE. This value was not exceeded for safety reasons and actuator power limit. The first set of tests began in nominal operating conditions; when 70% of SSE was reached, pressure feed to hydrostatic bearing was reduced lowering its effective support. This simulated a larger earthquake. The second set of tests was representative of SPX-1 pump actual operating conditions, because both hydrostatic bearing pressure and shaft rotating speed were simultaneously reduced following the primary pump characteristic curve. The tests allowed the SPX-1 pump rotating set to be widely qualified. Among the main results, it is worth noting that the stiffness of the hydrostatic bearing system was generally compatible with seismic requirements. Finally, it is worth pointing out that, in order to allow the above-mentioned tests to be carried out, a full seismic qualification of the CPV-1 test rig was necessary: thus, this rig might be used in the future for further seismic tests on LMFBR components and systems in sodium. (author). Figs and tabs

  18. Modeling and Simulation on Axial Piston Pump Based on Virtual Prototype Technology

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bin; XU Bing; XIA Chunlin; YANG Huayong

    2009-01-01

    A particular emphasis is placed on the virtual prototype technology (VPT) of axial piston pump. With this technology it is convenient and flexible to build a complicated 3D virtual based on real physical model. The actual kinematics pairs of the parts were added on the model. The fluid characters were calculated by hydraulic software. The shape of the parts, the flexible body of parts, etc were improved in this prototype. So the virtual prototype of piston pump can work in computer like a real piston pump, and the flow ripple, pressure pulsation, motion principle, stress of parts, etc can be investigated. The development of the VPT is introduced at the beginning, and the modeling process of the virtual prototype is explained. Then a special emphasis is laid on the relationship between the dynamics model and the hydraulic model, and the simulations on the flow ripple, pressure pulsation, motion principle, the stress and strain distribution of the middle shaft and piston are operated. Finally, the advantages and disadvantages of the VPT are discussed. The improved virtual prototype of piston pump more tally with the real situation and the VPT has a great potential in simulation on hydraulic components.

  19. Performance evaluation of organic and titanium based working fluids for high-temperature heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Zamfirescu, C., E-mail: Calin.Zamfirescu@uoit.ca [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (UOIT), 2000 Simcoe Street North, Oshawa, ON, Canada L1H 74K (Canada); Dincer, I., E-mail: Ibrahim.Dincer@uoit.ca [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (UOIT), 2000 Simcoe Street North, Oshawa, ON, Canada L1H 74K (Canada); Naterer, G., E-mail: Greg.Naterer@uoit.ca [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology (UOIT), 2000 Simcoe Street North, Oshawa, ON, Canada L1H 74K (Canada)

    2009-12-10

    In this paper, selected organic and titanium based fluids (biphenyl, biphenylmethane, naphthalene, isoquinoline, titanium tetrabromide and titanium tetraiodide) are assessed thermodynamically as potential working fluids for high temperature mechanical heat pumps. Various applications, such as thermo-chemical cycles for hydrogen production, chemical processes comprising endothermic reactions, steam generators and metallurgical processes, can benefit from such heat pumps as 'green' sources of high temperature heat. The environmental benefit occurs from avoiding fossil fuel heating and therefore reducing carbon dioxide and other pollutant emissions. Through heat pumps, a low-grade heat source from nuclear reactors, industrial waste, geothermal, etc. can be upgraded to high temperatures through a work-to-heat conversion. The work itself can originate from any source of renewable energy (wind, hydro, biomass, solar, etc.). In this paper, available thermo-physical parameters of the selected fluids are presented and appropriate equations of state are constructed to allow a heat pump thermodynamic analysis. Among these working fluids, only biphenyl, naphthalene, titanium tetrabromide and titanium tetraiodide have promising potential. For these fluids, a further parametric study is conducted to investigate the COP for a range of relevant operating conditions, in terms of temperature and pressure. The range of COP values is large, ranging from 1.9 to 7.3, depending on the fluid and temperature levels; the highest COP is obtained with TiI{sub 4}.

  20. Teaching the Fundamentals of Biological Research with Primary Literature: Learning from the Discovery of the Gastric Proton Pump

    Science.gov (United States)

    Zhu, Lixin

    2011-01-01

    For the purpose of teaching collegians the fundamentals of biological research, literature explaining the discovery of the gastric proton pump was presented in a 50-min lecture. The presentation included detailed information pertaining to the discovery process. This study was chosen because it demonstrates the importance of having a broad range of…

  1. Emergence of extreme events in fiber-based parametric processes driven by a partially incoherent pump wave.

    Science.gov (United States)

    Hammani, Kamal; Finot, Christophe; Millot, Guy

    2009-04-15

    We present experimental and theoretical results showing efficient emergence of rogue wavelike extreme intensity spikes during the fiber-based induced-modulational instability process driven by a partially incoherent pump. In particular, we show that the rogue event probability can be easily controlled by adjusting the pump-signal detuning. PMID:19370096

  2. Primary investigations on the potential of a novel diode pumped Er:YAG laser system for middle ear surgery

    Science.gov (United States)

    Stock, Karl; Wurm, Holger; Hausladen, Florian

    2016-02-01

    Flashlamp pumped Er:YAG lasers are successfully used clinically for both precise soft and hard tissue ablation. Since several years a novel diode pumped Er:YAG laser system (Pantec Engineering AG) is available, with mean laser power up to 40 W and pulse repetition rate up to 1 kHz. The aim of the study was to investigate the suitability of the laser system specifically for stapedotomy. Firstly an experimental setup was realized with a beam focusing unit and a computer controlled translation stage to move the samples (slices of porcine bone) with a defined velocity while irradiation with various laser parameters. A microphone was positioned in a defined distance to the ablation point and the resulting acoustic signal of the ablation process was recorded. For comparison, measurements were also performed with a flash lamp pumped Er:YAG laser system. After irradiation the resulting ablation quality and efficacy were determined using light microscopy. Using a high speed camera and "Töpler-Schlierentechnik" the cavitation bubble in water after perforation of a bone slice was investigated. The results show efficient bone ablation using the diode pumped Er:YAG laser system. Also a decrease of the sound level and of the cavitation bubble volume was observed with decreasing pulse duration. Higher repetition rates lead to a slightly increase of thermal side effects but have no influence on the ablation efficiency. In conclusion, these first experiments demonstrate the high potential of the diode pumped Er:YAG laser system for use in middle ear surgery.

  3. Prognostic for hydraulic pump based upon DCT-composite spectrum and the modified echo state network.

    Science.gov (United States)

    Sun, Jian; Li, Hongru; Xu, Baohua

    2016-01-01

    Prognostic is a key step of the condition-based maintenance (CBM). In order to improve the predicting performance, a novel method for prognostic for the hydraulic pump is proposed in this paper. Based on the improvement of the traditional composite spectrum, the DCT-composite spectrum (DCS) fusion algorithm is initially presented to make fusion of multi-channel vibration signals. The DCS composite spectrum entropy is extracted as the feature. Furthermore, the modified echo state networks (ESN) model is established for prognostic using the extracted feature. The reservoir is updated and the elements of the neighboring matrix are redefined for improving predicting accuracy. Analysis of the application in the hydraulic pump degradation experiment demonstrates that the proposed algorithm is feasible and is meaningful for CBM. PMID:27547667

  4. Temperature in the Primary Heat Transport Pump Bearing of the Nuclear Power Plant 'Embalse Rio Tercero' in view of the Cutting of the Service Water

    International Nuclear Information System (INIS)

    This study contains the analysis of the Primary Heat Transport Pump Bearing of the Nuclear Power Plant 'Embalse Rio Tercero', Cordoba, Argentine, in view of the cutting of the Service Water refrigeration which cools the Gland Seal System.This takes two ways: One is the study of the temperature rise of the water that cools the carbon bearing and the time involved.This is supported upon manuals and drawings.The other, on the temperature distribution in different operating conditions.This has been done by the simulation of the normal and transient conditions in the software COSMOS/M

  5. Dynamic stress analysis of sewage centrifugal pump impeller based on two-way coupling method

    Science.gov (United States)

    Pei, Ji; Yuan, Shouqi; Yuan, Jianping

    2014-03-01

    Current research on the operational reliability of centrifugal pumps has mainly focused on hydrodynamic instability. However, the interaction between the fluid and structure has not been sufficiently considered; this interaction can cause vibration and dynamic stress, which can affect the reliability. In this study, the dynamic stresses in a single-blade centrifugal pump impeller are analysed under different operating conditions; the two-way coupling method is used to calculate the fluid-structure interaction. Three-dimensional unsteady Reynolds-averaged Navier-Stokes equations are solved with the SST k-ω turbulence model for the fluid in the whole flow passage, while transient structure dynamic analysis is used with the finite element method for the structure side. The dynamic stresses in the rotor system are computed according to the fourth strength theory. The stress results show that the highest stress is near the loose bearing and that the equivalent stress increases with the flow rate because the dynamic stresses are closely related to the pressure load. The stress distributions on the blade pressure side, suction side, leading edge, and trailing edge are each analysed for different flow rates; the highest stress distribution is found on the pressure side. On the blade pressure side, a relatively large stress is found near the trailing edge and hub side. Based on these results, a stress distribution prediction method is proposed for centrifugal pumps, which considers the interaction between the fluid and structure. The method can be used to check the dynamic stress at different flow rates when optimising the pump design to increase the pump reliability.

  6. Study and Design of Diaphragm Pump Vibration Detection Fault Diagnosis System Based on FFT

    OpenAIRE

    Jia Yin; Jiande Wu; Xuyi Yuan; Xiaodong Wang; Yugang Fan

    2013-01-01

    This study has proposed a fault diagnosis system based on vibration detection. The system mainly includes four modules: signal acquisition module, signal processing module, state identification module, fault diagnosis and alarm module. The system uses CMSS 2200 acceleration sensor to collect vibration signals, processing spectrum with FFT (Fast Fourier Transform) which is used effectively in current industry and finally achieve fault diagnosis and prediction for diaphragm pump. Through collec...

  7. A PV/T and Heat Pump based trigeneration system model for residential applications

    OpenAIRE

    Joyce, António; Coelho, Luis; Martins, João F.; Tavares, Nelson; R Pereira; Magalhães, Pedro

    2011-01-01

    A solar trigeneration system, based on photovoltaic-thermal (PV/T) collectors, photovoltaic (PV) modules and a heat pump unit for heating and cooling, is modelled to forecast the thermal and electric yields of the system. The aim of the trigeneration system is to provide enough electricity, domestic hot water (DHW), heating and cooling power to meet the typical demand of an urban single family dwelling with limited roof area and allow the household to achieve a positive net energy status. The...

  8. A pressure control method for emulsion pump station based on Elman neural network.

    Science.gov (United States)

    Tan, Chao; Qi, Nan; Zhou, Xin; Liu, Xinhua; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others. PMID:25861253

  9. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    OpenAIRE

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was...

  10. A practical approach for implementing risk-based inservice testing of pumps at nuclear power plants

    International Nuclear Information System (INIS)

    The American Society of Mechanical Engineers (ASME) Center for Research and Technology Development's (CRTD) Research Task Force on Risk-Based Inservice Testing has developed guidelines for risk-based inservice testing (IST) of pumps and valves. These guidelines are intended to help the ASME Operation and Maintenance (OM) Committee to enhance plant safety while focussing appropriate testing resources on critical components. This paper describes a practical approach for implementing those guidelines for pumps at nuclear power plants. The approach, as described in this paper, relies on input, direction, and assistance from several entities such as the ASME Code Committees, United States Nuclear Regulatory Commission (NRC), and the National Laboratories, as well as industry groups and personnel with applicable expertise. Key parts of the risk-based IST process that are addressed here include: identification of important failure modes, identification of significant failure causes, assessing the effectiveness of testing and maintenance activities, development of alternative testing and maintenance strategies, and assessing the effectiveness of alternative testing strategies with present ASME Code requirements. Finally, the paper suggests a method of implementing this process into the ASME OM Code for pump testing

  11. A practical approach for implementing risk-based inservice testing of pumps at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, R.S. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Maret, D.; Seniuk, P.; Smith, L.

    1996-12-01

    The American Society of Mechanical Engineers (ASME) Center for Research and Technology Development`s (CRTD) Research Task Force on Risk-Based Inservice Testing has developed guidelines for risk-based inservice testing (IST) of pumps and valves. These guidelines are intended to help the ASME Operation and Maintenance (OM) Committee to enhance plant safety while focussing appropriate testing resources on critical components. This paper describes a practical approach for implementing those guidelines for pumps at nuclear power plants. The approach, as described in this paper, relies on input, direction, and assistance from several entities such as the ASME Code Committees, United States Nuclear Regulatory Commission (NRC), and the National Laboratories, as well as industry groups and personnel with applicable expertise. Key parts of the risk-based IST process that are addressed here include: identification of important failure modes, identification of significant failure causes, assessing the effectiveness of testing and maintenance activities, development of alternative testing and maintenance strategies, and assessing the effectiveness of alternative testing strategies with present ASME Code requirements. Finally, the paper suggests a method of implementing this process into the ASME OM Code for pump testing.

  12. Electro-osmotic pumping and ion-concentration polarization based on conical nanopores

    Science.gov (United States)

    Yeh, Hung-Chun; Chang, Chih-Chang; Yang, Ruey-Jen

    2015-06-01

    A numerical investigation is performed into the characteristics of an electro-osmotic pump consisting of a negatively charged conical nanopore. It is shown that the dependence of the flow rectification effect on the bias direction is the reverse of that of the ion current rectification effect. Moreover, the nozzle mode (i.e., the bias is applied from the base side of the nanopore to the tip side) has a higher flow rate compared to the diffuser mode (i.e., the bias is applied from the tip side of the nanopore to the base side). The results showed that the ion-concentration polarization effect occurred inside the conical nanopore, resulting in surface conduction dominating in the ionic current. The ions inside the nanopore are depleted and enriched under the nozzle mode and the diffuser mode, respectively. As a result, the electro-osmotic pump yields a greater pumping pressure, flow rate, and energy conversion efficiency when operating in the nozzle mode. In addition, we also investigated the flow rate rectification behavior for the conical nanopore. The best flow rate rectification factor in this work is 2.06 for an electrolyte concentration of 10-3M .

  13. Study and Design of Diaphragm Pump Vibration Detection Fault Diagnosis System Based on FFT

    Directory of Open Access Journals (Sweden)

    Jia Yin

    2013-02-01

    Full Text Available This study has proposed a fault diagnosis system based on vibration detection. The system mainly includes four modules: signal acquisition module, signal processing module, state identification module, fault diagnosis and alarm module. The system uses CMSS 2200 acceleration sensor to collect vibration signals, processing spectrum with FFT (Fast Fourier Transform which is used effectively in current industry and finally achieve fault diagnosis and prediction for diaphragm pump. Through collection and analysis of the history signal data, set threshold value in the fault diagnosis system. According to the characteristics of different types, set the corresponding effective threshold value. The simulation results show that, the spectrum after FFT transformation processing, can really and effectively reflect equipment operating condition of the diaphragm. This system is not only simple and stable, but also can predict pump failure effectively, so that it reduces equipment downtime, plan maintenance time and unplanned maintenance time.

  14. Thermodynamics of information processing based on enzyme kinetics: An exactly solvable model of an information pump

    Science.gov (United States)

    Cao, Yuansheng; Gong, Zongping; Quan, H. T.

    2015-06-01

    Motivated by the recent proposed models of the information engine [Proc. Natl. Acad. Sci. USA 109, 11641 (2012), 10.1073/pnas.1204263109] and the information refrigerator [Phys. Rev. Lett. 111, 030602 (2013), 10.1103/PhysRevLett.111.030602], we propose a minimal model of the information pump and the information eraser based on enzyme kinetics. This device can either pump molecules against the chemical potential gradient by consuming the information to be encoded in the bit stream or (partially) erase the information initially encoded in the bit stream by consuming the Gibbs free energy. The dynamics of this model is solved exactly, and the "phase diagram" of the operation regimes is determined. The efficiency and the power of the information machine is analyzed. The validity of the second law of thermodynamics within our model is clarified. Our model offers a simple paradigm for the investigating of the thermodynamics of information processing involving the chemical potential in small systems.

  15. SEQUENTIAL DIAGNOSIS FOR A CENTRIFUGAL PUMP BASED ON FUZZY NEURAL NETWORK

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiong; WANG Huaqing; CHEN Peng; TANG Yike

    2008-01-01

    A sequential diagnosis method is proposed based on a fuzzy neural network realized by "the partially-linearized neural network (PNN)", by which the fault types of rotating machinery can be precisely and effectively distinguished at an early stage on the basis of the possibilities of symptom parameters. The non-dimensional symptom parameters in time domain are defined for reflecting the features of time signals measured for the fault diagnosis of rotating machinery. The synthetic detection index is also proposed to evaluate the sensitivity of non-dimensional symptom parameters for detecting faults. The practical example of condition diagnosis for detecting and distinguishing fault states of a centrifugal pump system, such as cavitation, impeller eccentricity which often occur in a centrifugal pump system, are shown to verify the efficiency of the method proposed in this paper.

  16. THEORETICAL AND EXPERIMENTAL STUDY ON THE PRESSURE AND VACUUM CONTINUOUS CONTROL SYSTEM BASED ON HYBRID PUMP

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption of a fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.

  17. Thermodynamics of information processing based on enzyme kinetics: An exactly solvable model of an information pump.

    Science.gov (United States)

    Cao, Yuansheng; Gong, Zongping; Quan, H T

    2015-06-01

    Motivated by the recent proposed models of the information engine [Proc. Natl. Acad. Sci. USA 109, 11641 (2012)] and the information refrigerator [Phys. Rev. Lett. 111, 030602 (2013)], we propose a minimal model of the information pump and the information eraser based on enzyme kinetics. This device can either pump molecules against the chemical potential gradient by consuming the information to be encoded in the bit stream or (partially) erase the information initially encoded in the bit stream by consuming the Gibbs free energy. The dynamics of this model is solved exactly, and the "phase diagram" of the operation regimes is determined. The efficiency and the power of the information machine is analyzed. The validity of the second law of thermodynamics within our model is clarified. Our model offers a simple paradigm for the investigating of the thermodynamics of information processing involving the chemical potential in small systems. PMID:26172671

  18. Electrically pumped random lasing based on an Au-ZnO nanowire Schottky junction.

    Science.gov (United States)

    Gao, Fan; Morshed, Muhammad M; Bashar, Sunayna B; Zheng, Youdou; Shi, Yi; Liu, Jianlin

    2015-06-01

    Electrically pumped random lasing based on an Au-ZnO nanowire Schottky junction diode is demonstrated. The device exhibits typical Schottky diode current-voltage characteristics with a turn-on voltage of 0.7 V. Electroluminescence characterization shows good random lasing behavior and the output power is about 67 nW at a drive current of 100 mA. Excitonic recombination is responsible for lasing generation. Zn plasma is only observed under high applied bias, which can be distinguished from the random lasing spectral features near 380 nm. The laser diode based on the Schottky junction provides an alternative approach towards semiconductor random lasers. PMID:25946977

  19. Finite Volume Based Computer Program for Ground Source Heat Pump System

    Energy Technology Data Exchange (ETDEWEB)

    Menart, James A. [Wright State University

    2013-02-22

    This report is a compilation of the work that has been done on the grant DE-EE0002805 entitled ?Finite Volume Based Computer Program for Ground Source Heat Pump Systems.? The goal of this project was to develop a detailed computer simulation tool for GSHP (ground source heat pump) heating and cooling systems. Two such tools were developed as part of this DOE (Department of Energy) grant; the first is a two-dimensional computer program called GEO2D and the second is a three-dimensional computer program called GEO3D. Both of these simulation tools provide an extensive array of results to the user. A unique aspect of both these simulation tools is the complete temperature profile information calculated and presented. Complete temperature profiles throughout the ground, casing, tube wall, and fluid are provided as a function of time. The fluid temperatures from and to the heat pump, as a function of time, are also provided. In addition to temperature information, detailed heat rate information at several locations as a function of time is determined. Heat rates between the heat pump and the building indoor environment, between the working fluid and the heat pump, and between the working fluid and the ground are computed. The heat rates between the ground and the working fluid are calculated as a function time and position along the ground loop. The heating and cooling loads of the building being fitted with a GSHP are determined with the computer program developed by DOE called ENERGYPLUS. Lastly COP (coefficient of performance) results as a function of time are provided. Both the two-dimensional and three-dimensional computer programs developed as part of this work are based upon a detailed finite volume solution of the energy equation for the ground and ground loop. Real heat pump characteristics are entered into the program and used to model the heat pump performance. Thus these computer tools simulate the coupled performance of the ground loop and the heat pump

  20. Recovery Act: Finite Volume Based Computer Program for Ground Source Heat Pump Systems

    Energy Technology Data Exchange (ETDEWEB)

    James A Menart, Professor

    2013-02-22

    This report is a compilation of the work that has been done on the grant DE-EE0002805 entitled Finite Volume Based Computer Program for Ground Source Heat Pump Systems. The goal of this project was to develop a detailed computer simulation tool for GSHP (ground source heat pump) heating and cooling systems. Two such tools were developed as part of this DOE (Department of Energy) grant; the first is a two-dimensional computer program called GEO2D and the second is a three-dimensional computer program called GEO3D. Both of these simulation tools provide an extensive array of results to the user. A unique aspect of both these simulation tools is the complete temperature profile information calculated and presented. Complete temperature profiles throughout the ground, casing, tube wall, and fluid are provided as a function of time. The fluid temperatures from and to the heat pump, as a function of time, are also provided. In addition to temperature information, detailed heat rate information at several locations as a function of time is determined. Heat rates between the heat pump and the building indoor environment, between the working fluid and the heat pump, and between the working fluid and the ground are computed. The heat rates between the ground and the working fluid are calculated as a function time and position along the ground loop. The heating and cooling loads of the building being fitted with a GSHP are determined with the computer program developed by DOE called ENERGYPLUS. Lastly COP (coefficient of performance) results as a function of time are provided. Both the two-dimensional and three-dimensional computer programs developed as part of this work are based upon a detailed finite volume solution of the energy equation for the ground and ground loop. Real heat pump characteristics are entered into the program and used to model the heat pump performance. Thus these computer tools simulate the coupled performance of the ground loop and the heat pump. The

  1. A dynamic model of mobile concrete pump boom based on discrete time transfer matrix method

    Science.gov (United States)

    Ren, Wu; Wu, Yunxin; Zhang, Zhaowei

    2013-12-01

    Mobile concrete pump boom is typical multibody large-scale motion manipulator. Due to posture constantly change in working process, kinematic rule and dynamic characteristic are difficult to solve. A dynamics model of a mobile concrete pump boom is established based on discrete time transfer matrix method (DTTMM). The boom system is divided into sub-structure A and substructure B. Sub-structure A is composed by the 1st boom and hydraulic actuator as well as the support. And substructure B is consists of the other three booms and corresponding hydraulic actuators. In the model, the booms and links are regarded as rigid elements and the hydraulic cylinders are equivalent to spring-damper. The booms are driven by the controllable hydraulic actuators. The overall dynamic equation and transfer matrix of the model can be assembled by sub-structures A and B. To get a precise result, step size and integration parameters are studied then. Next the tip displacement is calculated and compared with the result of ADAMS software. The displacement and rotation angle curves of the proposed method fit well with the ADAMS model. Besides it is convenient in modeling and saves time. So it is suitable for mobile concrete pump boom real-time monitoring and dynamic analysis. All of these provide reference to boom optimize and engineering application of such mechanisms.

  2. Optimum IMFs Selection Based Envelope Analysis of Bearing Fault Diagnosis in Plunger Pump

    Directory of Open Access Journals (Sweden)

    Wenliao Du

    2016-01-01

    Full Text Available As the plunger pump always works in a complicated environment and the hydraulic cycle has an intrinsic fluid-structure interaction character, the fault information is submerged in the noise and the disturbance impact signals. For the fault diagnosis of the bearings in plunger pump, an optimum intrinsic mode functions (IMFs selection based envelope analysis was proposed. Firstly, the Wigner-Ville distribution was calculated for the acquired vibration signals, and the resonance frequency brought on by fault was obtained. Secondly, the empirical mode decomposition (EMD was employed for the vibration signal, and the optimum IMFs and the filter bandwidth were selected according to the Wigner-Ville distribution. Finally, the envelope analysis was utilized for the selected IMFs filtered by the band pass filter, and the fault type was recognized by compared with the bearing character frequencies. For the two modes, inner race fault and compound fault in the inner race and roller of rolling element bearing in plunger pump, the experiments show that a promising result is achieved.

  3. Analysis on the blade inlet pressure fluctuation of the centrifugal pump based on LES

    International Nuclear Information System (INIS)

    In order to study the characteristics of the blade inlet pressure fluctuation under unsteady flow in centrifugal pump, a three-dimensional model of a pump ns=50 was built. Based on large eddy simulation (LES), the inner flow field of the pump was simulated by the flow field simulation software Fluent in design condition and off-design conditions. The pressure fluctuation of the monitored points was obtained at the blade suction surface and pressure surface at impeller inlet, which was analyzed by time and frequency domain with Fast Fourier Transformation (FFT). The results show that the pressure fluctuation of inlet and outlet in large flow rate is more obvious than low flow rate. It is easily found that the static pressure of outlet in 1.2Qd condition has five peaks and five valleys, but this phenomenon does not exist in 0.6 Qd condition. In the time domain spectrums, the static pressure curve has five peaks and five valleys that the maximum pressure is positive number and the minimum pressure is negative number. In the frequency domains spectrums, the frequency of FFT factors peak is lower than the blade passing frequency 241.65Hz

  4. Global design optimization for an axial-flow tandem pump based on surrogate method

    Science.gov (United States)

    Li, D. H.; Zhao, Y.; Y Wang, G.

    2013-12-01

    Tandem pump, compared with multistage pump, goes without guide vanes between impellers. Better cavitation performance and significant reduction of the axial geometry scale is important for high-speed propulsion. This study presents a global design optimization method based on surrogated method for an axial-flow tandem pump to enhance trade-off performances: energy and cavitation performances. At the same time, interactions between impellers and impacts on the performances are analyzed. Fixed angle of blades in impellers and phase angle are performed as design variables. Efficiency and minimum average pressure coefficient (MAPC) on axial sectional surface in front impeller are the objective function, which can represent energy and cavitation performances well. Different surrogate models are constructed, and Global Sensitivity Analysis and Pareto Front method are used. The results show that, 1) Influence from phase angle on performances can be neglected compared with other two design variables, 2) Impact ratio of fixed angle of blades in two impellers on efficiency are the same as their designed loading distributions, which is 4:6, 3) The optimization results can enhance the trade-off performances well: efficiency is improved by 0.6%, and the MAPC is improved by 4.5%.

  5. Analysis on the blade inlet pressure fluctuation of the centrifugal pump based on LES

    Science.gov (United States)

    Wang, W. J.; Cui, Y. R.; Wang, Y.; Li, G. D.; Liang, Q. H.; Yin, G.

    2013-12-01

    In order to study the characteristics of the blade inlet pressure fluctuation under unsteady flow in centrifugal pump, a three-dimensional model of a pump ns=50 was built. Based on large eddy simulation (LES), the inner flow field of the pump was simulated by the flow field simulation software Fluent in design condition and off-design conditions. The pressure fluctuation of the monitored points was obtained at the blade suction surface and pressure surface at impeller inlet, which was analyzed by time and frequency domain with Fast Fourier Transformation (FFT). The results show that the pressure fluctuation of inlet and outlet in large flow rate is more obvious than low flow rate. It is easily found that the static pressure of outlet in 1.2Qd condition has five peaks and five valleys, but this phenomenon does not exist in 0.6 Qd condition. In the time domain spectrums, the static pressure curve has five peaks and five valleys that the maximum pressure is positive number and the minimum pressure is negative number. In the frequency domains spectrums, the frequency of FFT factors peak is lower than the blade passing frequency 241.65Hz.

  6. Global design optimization for an axial-flow tandem pump based on surrogate method

    International Nuclear Information System (INIS)

    Tandem pump, compared with multistage pump, goes without guide vanes between impellers. Better cavitation performance and significant reduction of the axial geometry scale is important for high-speed propulsion. This study presents a global design optimization method based on surrogated method for an axial-flow tandem pump to enhance trade-off performances: energy and cavitation performances. At the same time, interactions between impellers and impacts on the performances are analyzed. Fixed angle of blades in impellers and phase angle are performed as design variables. Efficiency and minimum average pressure coefficient (MAPC) on axial sectional surface in front impeller are the objective function, which can represent energy and cavitation performances well. Different surrogate models are constructed, and Global Sensitivity Analysis and Pareto Front method are used. The results show that, 1) Influence from phase angle on performances can be neglected compared with other two design variables, 2) Impact ratio of fixed angle of blades in two impellers on efficiency are the same as their designed loading distributions, which is 4:6, 3) The optimization results can enhance the trade-off performances well: efficiency is improved by 0.6%, and the MAPC is improved by 4.5%

  7. A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

    Institute of Scientific and Technical Information of China (English)

    Linhui ZHAO; Xin FANG

    2009-01-01

    Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150℃ and 28MPa to overcome problems of traditional high-temperature plun-ger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90℃ phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mono-neuron self-adaptive PID control algorithm is also improved by modifying parameters K and η. Two improved controllers are used to control the two cylinders,respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

  8. Automated Web-based Monitoring of a Pump and Treat System at the Hanford Site

    Science.gov (United States)

    Webber, W.; Versteeg, R.; Richardson, A.; Ankeny, M.; Gilmore, T.; Morse, J.; Thompson, M.

    2006-05-01

    Automated and autonomous monitoring of environmental conditions can be used to improve operational efficiency, verify remedial action decisions, and promote confidence in the monitoring process by making data and associated derived information readily accessible to regulators and stakeholders. Ultimately autonomous monitoring systems can reduce overall costs associated with regulatory compliance of performance and long- term monitoring. As part of a joint decision between DOE and the WA Department of Ecology to put on "cold standby" a pump and treat system that has been operating on the Department of Energy's Hanford site in Washington State since 1995, a web site was developed to display the automated water level network around the pump and treat system. The automated water level network consists of nineteen wells with water level transducers and temperature and conductivity probes for selected wells. Data from this network will be used to evaluate the impacts of the pump-and-treat system and the response of the aquifer to shutdown of the system. The website will provide access to data from the automated network along with additional information pertaining to the shutdown of the pump and treat system to the various stakeholders in a convenient and timely fashion. This will allow the various stakeholders to observe the impacts of the shutdown as the aquifer responds. There are future plans to expand this web-based data reporting platform to other environmental data that pertains to the various remedial actions planned at the Hanford site. The benefits of the web site application for monitoring and stewardship are: consistency of data processing and analyses with automated and on demand data and information delivery. The system and data access is password controlled and access to various data or fields can be restricted to specified users. An important feature is that the stakeholders have access to the data in near-real time providing a checks-and-balance system

  9. Model predictive control of servo motor driven constant pump hydraulic system in injection molding process based on neurodynamic optimization

    Institute of Scientific and Technical Information of China (English)

    Yong-gang PENG; Jun WANG; Wei WEI

    2014-01-01

    In view of the high energy consumption and low response speed of the traditional hydraulic system for an injection molding machine, a servo motor driven constant pump hydraulic system is designed for a precision injection molding process, which uses a servo motor, a constant pump, and a pressure sensor, instead of a common motor, a constant pump, a pressure pro-portion valve, and a flow proportion valve. A model predictive control strategy based on neurodynamic optimization is proposed to control this new hydraulic system in the injection molding process. Simulation results showed that this control method has good control precision and quick response.

  10. Vane Pump Casing Machining of Dumpling Machine Based on CAD/CAM

    Science.gov (United States)

    Huang, Yusen; Li, Shilong; Li, Chengcheng; Yang, Zhen

    Automatic dumpling forming machine is also called dumpling machine, which makes dumplings through mechanical motions. This paper adopts the stuffing delivery mechanism featuring the improved and specially-designed vane pump casing, which can contribute to the formation of dumplings. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on UG and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.

  11. Disulphide cross linked pullulan based cationic polymer for improved gene delivery and efflux pump inhibition.

    Science.gov (United States)

    S, Priya S; R, Rekha M

    2016-10-01

    Multidrug resistance is a hurdle to successful cancer chemotherapy. Over expression of P-glycoprotein (P-gp) is a prime contributing factor for drug resistance. In this study, a disulphide cross-linked pullulan-based cationic polymer (PPSS) was synthesized to act simultaneously as gene delivery vehicle and efflux pump inhibitor. The PPSS nanoplexes were of size p53/PPSS/DOX nanoplexes was attributed to the synergistic effect of P-gp inhibition and p53 transfection efficiency. Therefore, this multifunctional polymeric system may have significant promise for therapeutic application against cancer drug resistance. PMID:27459414

  12. Low-noise delays from dynamic Brillouin gratings based on perfect Golomb coding of pump waves.

    Science.gov (United States)

    Antman, Yair; Levanon, Nadav; Zadok, Avi

    2012-12-15

    A method for long variable all-optical delay is proposed and simulated, based on reflections from localized and stationary dynamic Brillouin gratings (DBGs). Inspired by radar methods, the DBGs are inscribed by two pumps that are comodulated by perfect Golomb codes, which reduce the off-peak reflectivity. Compared with random bit sequence coding, Golomb codes improve the optical signal-to-noise ratio (OSNR) of delayed waveforms by an order of magnitude. Simulations suggest a delay of 5  Gb/s data by 9 ns, or 45 bit durations, with an OSNR of 13 dB. PMID:23258071

  13. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    Directory of Open Access Journals (Sweden)

    Chao Tan

    2015-01-01

    Full Text Available In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  14. The Development of Gear Pump CAD/CAPP Based on Solid Works

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nowadays, many kinds of software, which have succes sf ully created the integration of CAD, CAPP and CAM, find their disadvantages in p ractical manufacturing. As a result, it is welcomed to develop small CAD/CAPP sy stems on a proper CAD platform, which aim at requirements of factories. Based on the one of the most popular three-dimensional design software SolidWorks, we successfully developed a set of gear pump CAD /CAPP software for Huaiyin Gene ral Factory of Mechanics. 1 The architecture and func...

  15. Small-signal modelling and control of photovoltaic based water pumping system.

    Science.gov (United States)

    Ghosh, Arun; Ganesh Malla, Siva; Narayan Bhende, Chandrasekhar

    2015-07-01

    This paper studies small-signal modelling and control design for a photovoltaic (PV) based water pumping system without energy storage. First, the small-signal model is obtained and then, using this model, two proportional-integral (PI) controllers, where one controller is used to control the dc-link voltage and the other one to control the speed of induction motor, are designed to meet control goals such as settling time and peak overshoot of the closed loop responses. The loop robustness of the design is also studied. For a given set of system parameters, simulations are carried out to validate the modelling and the control design. PMID:25707717

  16. Alternative ethanol based cooling carriers with corrosion inhibitors in geothermal heat pump systems

    OpenAIRE

    Gustafsson, Isac

    2015-01-01

    Ground source heat pumps are very popular in the Nordic countries. The method of exchanging heat with the ground is based on the principle that a secondary fluid is circulating through a U-pipe borehole heat exchanger inserted into energy wells. Water is a very good secondary fluid, but aqueous solutions of ethanol are recommended in Sweden as a secondary fluid for such application. One reason is the fact that addition of ethanol decreases the freezing point of the fluid, which is preferred s...

  17. Helmholtz resonance in a piezoelectric–hydraulic pump-based hybrid actuator

    International Nuclear Information System (INIS)

    This paper demonstrates that a hydraulically acting Helmholtz resonator can exist in a piezoelectric–hydraulic pump (PHP) based hybrid actuator, which in turn affects the volumetric efficiency of the PHP. The simulation and experimental results illustrate the effect of Helmholtz resonance on the flow rate performance of the PHP. The study also shows how to shift the Helmholtz resonant frequency to a higher value through changing parameters such as the cylinder diameter and the effective bulk modulus of the working fluid, which will improve the volumetric efficiency and broaden the operating frequency range of the PHP actuator

  18. Generating an indicator for pump impeller damage using half and full spectra, fuzzy preference-based rough sets and PCA

    International Nuclear Information System (INIS)

    Parameters that vary monotonically with damage propagation are useful in condition monitoring. However, it is not easy to find such parameters especially for complex systems like pumps. A method using half and full spectra, fuzzy preference-based rough sets and principal component analysis (PCA) is proposed to generate such an indicator for tracking impeller damage in a centrifugal slurry pump. Half and full spectra are used for extracting features related to pump health status. A fuzzy preference-based rough set model is employed in the process of selecting features reflecting the damage propagation monotonically. PCA is used to condense the features and generate an indicator which represents the damage propagation. The effectiveness of the proposed method is tested using laboratory experimental data. Results show that the indicator generated by the proposed method can clearly and monotonically distinguish the health status of the pump impeller. (paper)

  19. Investigation of pump-wavelength dependence of terahertz-wave parametric oscillator based on LiNbO3

    International Nuclear Information System (INIS)

    This paper investigates the performances of terahertz-wave parametric oscillators (TPOs) based on the LiNbO3 crystal at different pump wavelengths. The calculated results show that TPO characteristics, including the frequency tuning range, the THz-wave gain and the stability of THz-wave output direction based on the Si-prism coupler, can be significantly improved by using a short-wavelength pump. It also demonstrates that a long-wavelength-pump allows the employment of a short TPO cavity due to an enlarged phase-matching angle, that is, an increased angular separation between the pump and oscillated Stokes beams under the THz-wave generation at a specific frequency. The study provides an useful guide and a theoretical basis for the further improvement of TPO systems. (classical areas of phenomenology)

  20. Predicting performance of axial pump inducer of LOX booster turbo-pump of staged combustion cycle based rocket engine using CFD

    Science.gov (United States)

    Mishra, Arpit; Ghosh, Parthasarathi

    2015-12-01

    For low cost, high thrust, space missions with high specific impulse and high reliability, inert weight needs to be minimized and thereby increasing the delivered payload. Turbopump feed system for a liquid propellant rocket engine (LPRE) has the highest power to weight ratio. Turbopumps are primarily equipped with an axial flow inducer to achieve the high angular velocity and low suction pressure in combination with increased system reliability. Performance of the turbopump strongly depends on the performance of the inducer. Thus, for designing a LPRE turbopump, demands optimization of the inducer geometry based on the performance of different off-design operating regimes. In this paper, steady-state CFD analysis of the inducer of a liquid oxygen (LOX) axial pump used as a booster pump for an oxygen rich staged combustion cycle rocket engine has been presented using ANSYS® CFX. Attempts have been made to obtain the performance characteristic curves for the LOX pump inducer. The formalism has been used to predict the performance of the inducer for the throttling range varying from 80% to 113% of nominal thrust and for the different rotational velocities from 4500 to 7500 rpm. The results have been analysed to determine the region of cavitation inception for different inlet pressure.

  1. Large electromagnetic pumps. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Kilman, G.B.

    1976-01-01

    The development of large electromagnetic pumps for the liquid metal heat transfer systems of fission reactors has progressed for a number of years. Such pumps are now planned for fusion reactors and solar plants as well. The Einstein-Szilard (annular) pump has been selected as the preferred configuration. Some of the reasons that electromagnetic pumps may be preferred over mechanical pumps and why the annular configuration was selected are discussed. A detailed electromagnetic analysis of the annular pump, based on slug flow, is presented. The analysis is then used to explore the implications of large size and power on considerations of electromagnetic skin effect, geometric skin effect and the cylindrical geometry.

  2. MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM

    Institute of Scientific and Technical Information of China (English)

    YU Shitao; YANG Shiwei; YANG Lin; GONG Yuanming; ZHUO Bin

    2007-01-01

    A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased.

  3. Comparison of tunable lasers based on diode pumped Tm-doped crystals

    Science.gov (United States)

    Šulc, Jan; Jelínková, Helena; Koranda, Petr; Černý, Pavel; Jabczyński, Jan K.; Żendzian, Waldemar; Kwiatkowski, Jacek; Urata, Yoshiharu; Higuchi, Mikio

    2008-12-01

    We report on continuously tunable operation of a diode pumped lasers based on Tm-doped materials, emitting in the 1.8 - 2.μ1 m spectral band. In our study we compare results obtained with three various single crystals doped by Tm3+ ions: Yttrium Aluminum perovskite YAP (YAlO3), Gadolinium orthovanadate GdVO4, and Yttrium Lithium Fluoride YLF (YLiF4). Following samples were available: the 3mm long a-cut crystal rod of Tm:YAP with 4% at. Tm/Y (diameter 3 mm); the 8mm long b-cut crystal rod of Tm:YLF with 3.5% at. Tm/Y (diameter 3 mm); the 2.7mm long a-cut crystal block of Tm:GdVO4 with 2% at. Tm/Gd (crystal face 5×3 mm). For active medium pumping, the laser diode radiation was used. Because the tested samples differs significantly in absorption spectra, two fibre-coupled (core diameter 400 µm) temperature-tuned laser diodes were used: first operating at wavelength 793nm was used for Tm:YAP and Tm:YLF; the second operating at wavelength 802nm was used for Tm:GdVO4. In both cases, the continuous power up to 20W was available for pumping. The diode radiation was focused into the active crystal by two achromatic doublet lenses with the focal length f = 75 mm. The measured radius of pumping beam focus inside the crystal was 260 µm. The longitudinally diode pumped crystals were tested in linear, 80mm long, hemispherical laser cavity. The curved (radius 150mm) output coupler reflectivity was ~ 97 % in range from 1.8 up to 2.1 μm. The pumping flat mirror had maximal reflectivity in this range and it had high transmission around 0.8 μm. A 1.5mm thick birefringent plate made from quartz (Lyot filter) inserted under a Brewster's angle was used as a tuning element. This plate was placed inside the resonator between the crystal and the output coupler. Using Tm:YAP crystal, the maximal output power of 2.8W in this set-up was obtained. The laser could be tuned from 1865nm up to 2036nm with a maximum at 1985 nm. Laser based on Tm:YLF crystal was tunable from 1835nm up to

  4. Small Scroll Pump for Cryogenic Liquids Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a compact, reliable, light weight, electrically driven pump capable of pumping cryogenic liquids, based on scroll pump technology. This pump will...

  5. Research of factors influencing centrifugal pump external characteristics based on orthogonal test

    International Nuclear Information System (INIS)

    In order to investigate the impact on external characteristics of single-stage and single-suction centrifugal pump, four parameters: cutwater gap(δ), blade number(z), impeller outlet width(b) and blade outlet angle(β) were taken into account. Orthogonal test method is a method which can make a comprehensive comparison among factors we are interested in. Thereby, it can't be more appropriate to adopt this approach to study the influence of the four factors referred above. Based on the prototype pump's geometric parameters, each of these factors took four levels. According to the principle of selecting orthogonal array, the L16(45) array was selected and 16 models were designed. After that, commercial CFD software CFX was used to calculate the head and efficiency under different conditions to determine the optimal operating condition Qr. The 16 models' rated flow rates were basically smaller than the prototype's. Considering this difference, in order to analyze the influence on the head under similar condition, the flow rate was made dimensionless and 3 conditions are chosen(Qr/Q=1, 1.25 and 1.375). Through the analysis of averaged respond head and efficiency, the laws of head and efficiency changing with the variation of the factors were obtained. Commonly, if a dependent's change cause by a independent variable is smaller than 5%, we can neglect the independent variable's effect. Thus the paper presents a research showing the factors' changing limitations considering the head changing by a percentage smaller than 5%. The conclusion of this article has important reference value for design of centrifugal pumps

  6. Generation of synchronized signal and pump pulses for an optical parametric chirped pulse amplification based multi-terawatt Nd:glass laser system

    Indian Academy of Sciences (India)

    M Raghuramaiah; R K Patidar; R A Joshi; P A Naik; P D Gupta

    2010-11-01

    Synchronized signal (650 ps) and pump (1.3 ns) pulses were generated using 4-pass geometry in a grating pair based pulse stretcher unit. The pump pulse has been further amplified in a high gain regenerative amplifier. This amplified pulse was used as the pump in an optical parametric chirped pulse amplification based Nd:glass laser system. As the chirped signal pulse and the pump pulse originated from the same oscillator, the time jitter between the pump pulse and the signal pulse can be <50 ps.

  7. Excited state Faraday anomalous dispersion optical filters based on indirect laser pumping.

    Science.gov (United States)

    Yin, Longfei; Luo, Bin; Chen, Zhongjie; Zhong, Lei; Guo, Hong

    2014-02-15

    The direct pump method now used in excited state Faraday anomalous dispersion optical filters (ES-FADOFs) requires that the transition between the target and the ground state is an electric dipole allowed transition and that a laser that operates at the exact pump wavelength is available. This is not always satisfied in practice. An indirect laser pump method for ES-FADOF is proposed and experimentally realized. Compared with the commonly used direct pump method, this indirect pump method can reach the same performance using lasers at very different wavelengths. This method can greatly extend the wavelength range of FADOF and provide a novel scheme for ES-FADOF design. PMID:24562221

  8. A C-terminal tyrosine-based motif in the bile salt export pump directs clathrin-dependent endocytosis

    OpenAIRE

    Lam, Ping; Xu, Shuhua; Soroka, Carol J.; Boyer, James L.

    2012-01-01

    The liver specific bile salt export pump (BSEP) is crucial for bile-acid dependent bile flow at the apical membrane. BSEP, a member of the family of structurally related ATP-Binding Cassette (ABC) proteins, is composed of 12 transmembrane segments (TMS) and 2 large cytoplasmic nucleotide binding domains (NBD). The regulation of trafficking of BSEP to and from the cell surface is not well understood, but is believed to play an important role in cholestatic liver diseases such as primary famili...

  9. Jet pumps for thermoacoustic applications: design guidelines based on a numerical parameter study

    CERN Document Server

    Oosterhuis, Joris P; Wilcox, Douglas; van der Meer, Theo H

    2015-01-01

    The oscillatory flow through tapered cylindrical tube sections (jet pumps) is characterized by a numerical parameter study. The shape of a jet pump results in asymmetric hydrodynamic end effects which cause a time-averaged pressure drop to occur under oscillatory flow conditions. Hence, jet pumps are used as streaming suppressors in closed-loop thermoacoustic devices. A two-dimensional axisymmetric computational fluid dynamics model is used to calculate the performance of a large number of conical jet pump geometries in terms of time-averaged pressure drop and acoustic power dissipation. The investigated geometrical parameters include the jet pump length, taper angle, waist diameter and waist curvature. In correspondence with previous work, four flow regimes are observed which characterize the jet pump performance and dimensionless parameters are introduced to scale the performance of the various jet pump geometries. The simulation results are compared to an existing quasi-steady theory and it is shown that t...

  10. A high carrier injection terahertz quantum cascade laser based on indirectly pumped scheme

    International Nuclear Information System (INIS)

    A Terahertz quantum cascade laser with a rather high injection coupling strength based on an indirectly pumped scheme is designed and experimentally implemented. To effectively suppress leakage current, the chosen quantum cascade module of the device is based on a five-well GaAs/Al0.25Ga0.75As structure. The device lases up to 151 K with a lasing frequency of 2.67 THz. This study shows that the effect of higher energy states in carrier transport and the long-range tunnel coupling between states that belong to non-neighbouring modules have to be considered in quantum design of structures with a narrow injector barrier. Moreover, the effect of interface roughness scattering between the lasing states on threshold current is crucial

  11. A high carrier injection terahertz quantum cascade laser based on indirectly pumped scheme

    Energy Technology Data Exchange (ETDEWEB)

    Razavipour, S. G., E-mail: sgrazavi@uwaterloo.ca; Xu, C.; Wasilewski, Z. R.; Ban, D. [Department of Electrical and Computer Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Ave. W., Waterloo, Ontario N2L3G1 (Canada); Dupont, E.; Laframboise, S. R. [National Research Council, Blg. M-50, 1200 Montreal Rd., Ottawa, Ontario K1A0R6 (Canada); Chan, C. W. I.; Hu, Q. [Department of Electrical Engineering and Computer Science, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2014-01-27

    A Terahertz quantum cascade laser with a rather high injection coupling strength based on an indirectly pumped scheme is designed and experimentally implemented. To effectively suppress leakage current, the chosen quantum cascade module of the device is based on a five-well GaAs/Al{sub 0.25}Ga{sub 0.75}As structure. The device lases up to 151 K with a lasing frequency of 2.67 THz. This study shows that the effect of higher energy states in carrier transport and the long-range tunnel coupling between states that belong to non-neighbouring modules have to be considered in quantum design of structures with a narrow injector barrier. Moreover, the effect of interface roughness scattering between the lasing states on threshold current is crucial.

  12. Transition to an elastomeric infusion pump in home care: an evidence-based approach.

    Science.gov (United States)

    Broadhurst, Daphne

    2012-01-01

    A fatal overdose of a chemotherapeutic agent delivered to a patient via an electronic infusion device served as a stark reminder of the risks that infusion therapy poses to patients and health care providers and as the impetus for a strategy to optimize safe and efficient delivery of home infusion therapy. The Academic Center for Evidence-Based Practice Star Model of Knowledge Transformation was used as the evidence-based framework for the implementation of a portable infusion pump that supports home infusion of high-risk medications, leading to increased patient and caregiver satisfaction. Evaluation of this implementation supports the use of an elastomeric infusion device for a high-risk therapy. PMID:22498484

  13. Analysis on pressure characteristics of pump turbine guide bearing rotating sump based on VOF model

    International Nuclear Information System (INIS)

    With the technology of Computational Fluid Dynamics (CFD), this paper conducts a 3D numerical simulation for the oil and gas flow field in the Pump turbine guide bearing rotating sump. VOF model is adopted in this simulation. This study calculates distribution of the oil-air phase and characteristics of the pressure. The influence of sump rotating speed, oil level and oil viscosity on the pressure at the inlet of oil-immersion plate are discussed. The results demonstrate that the static pressure at the inlet is roughly proportional to oil level. Too low level may result in the separation between lubrication oil and supply hole on the oil-immersion plate, which then disables the oil supply. The static pressure at the inlet increases parabola as the sump rotating speed increases. To ensure the supply pressure, the unit is not suitable for long time operation under low rotating speed. The temperature-viscosity effect of the lubricant oil has little influence on the oil pressure at the supply hole. This paper provides a theoretical base for the safe design and operation of the pump turbine rotating sump, and offers the inlet boundary condition for the analysis of the oil film dynamic characteristics of the turbine guide bearing

  14. MBE growth of active regions for electrically pumped, cw-operating GaSb-based VCSELs

    Science.gov (United States)

    Kashani-Shirazi, K.; Bachmann, A.; Boehm, G.; Ziegler, S.; Amann, M.-C.

    2009-03-01

    Electrically pumped, cw-operating, single-mode GaSb-based VCSELs are attractive light sources for trace-gas sensing systems using tunable diode laser absorption spectroscopy (TDLAS) [A. Vicet, D.A. Yarekha, A. Pérona, Y. Rouillard, S. Gaillard, Spectrochimica Acta Part A 58 (2002) 2405-2412]. Only recently, the first electrically pumped (EP) devices emitting at 2.325 μm in cw-mode at room temperature have been reported [A. Bachmann, T. Lim, K. Kashani-Shirazi, O. Dier, C. Lauer, M.-C. Amann, Electronics Letters 44(3) (2008) 202-203]. The fabrication of these devices employs the molecular beam epitaxy (MBE) growth of GaSb/AlAsSb-distributed Bragg mirrors, a multi-quantum-well active region made of AlGaAsSb/InGaAsSb and an InAsSb/GaSb-buried-tunnel junction. As VCSELs are usually driven under high injection rates, an optimum electrical design of active regions is essential for high-performance devices. In this paper we present an enhanced simulation of current flow in the active region under operation conditions. The calculation includes carrier transport by drift, diffusion and tunneling. We discuss different design criteria and material compositions for active regions. Active regions with various barrier materials were incorporated into edge emitter samples to evaluate their performance. Aluminum-containing barriers show better internal efficiency compared to active regions with GaSb as the barrier material.

  15. Expression and functioning of retinal-based proton pumps in a saltern crystallizer brine.

    Science.gov (United States)

    Oren, Aharon; Abu-Ghosh, Said; Argov, Tal; Kara-Ivanov, Eliahu; Shitrit, Dror; Volpert, Adi; Horwitz, Rael

    2016-01-01

    We examined the presence of bacteriorhodopsin and other retinal protein pigments in the microbial community of the saltern crystallizer ponds in Eilat, Israel, and assessed the effect of the retinal-based proton pumps on the metabolic activity. The biota of the hypersaline (~309 g salts l(-1)) brine consisted of ~2200 β-carotene-rich Dunaliella cells and ~3.5 × 10(7) prokaryotes ml(-1), most of which were flat, square or rectangular Haloquadratum-like archaea. No indications were obtained for massive presence of Salinibacter. We estimated a concentration of bacteriorhodopsin and bacteriorhodopsin-like pigments of 3.6 nmol l(-1). When illuminated, the community respiration activity of the brine samples in which oxygenic photosynthesis was inhibited by 3-(3-4-dichlorophenyl)-1,1-dimethylurea, decreased by 40-43 %. This effect was interpreted to be the result of competition between two energy yielding systems: the bacteriorhodopsin proton pump and the respiratory chain. The results presented have important implications for the interpretation of many published data on photosynthetic and respiratory activities in hypersaline environments. PMID:26507954

  16. Characterization of a ferrofluid-based thermomagnetic pump for microfluidic applications

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Souvik; Datta, Amitava [Department of Power Engineering, Jadavpur University, Kolkata 700098 (India); Sen, Swarnendu; Mukhopdhyay, Achintya [Department of Mechanical Engineering, Jadavpur University, Kolkata 700032 (India); Bandopadhyay, Kallol [Machine Dynamics Division, BARC, Trombay, Mumbai 400085 (India); Ganguly, Ranjan, E-mail: ranjan@pe.jusl.ac.in [Department of Power Engineering, Jadavpur University, Kolkata 700098 (India)

    2011-11-15

    We experimentally characterize the performance of a miniature thermomagnetic pump, where suitably imposed temperature and magnetic field gradients are used to drive ferrofluid in a 2 mm diameter glass capillary tube, without application of any external pressure gradient. Such a pump can operate in a hermetically sealed micro electromechanical system configuration without any moving part, and is thus capable of handling microfluidic samples with little risk of contamination. In the experiment, the ferrofluid in the capillary is exposed to a magnetic field using a solenoid; a small resistive heater wrapped on the tube wall is used to create temperature gradient in such a way that the Kelvin body force in the medium produces a net unbalanced axial component. This causes a thermomagnetic pumping action, transporting the ferrofluid in the capillary tube from the colder end to the warmer end. Performance of the thermomagnetic pump is investigated experimentally to characterize the pump pressure head and discharge under different working conditions, namely, the magnetic field strength, heating power, and ferrofluid properties. A comparison with two other field actuation pumps at comparable length scales is also presented. The pump produces higher output at lower power supplies and magnetic field compared to the other two pumps. - Highlights: > Operation of a miniature thermomagnetic pump is demonstrated and its performance is characterized. > Performance of the thermomagnetic pump is investigated experimentally to characterize the pump pressure head. > The discharge occurs under different working conditions, namely, the magnetic field strength, heating power, and ferrofluid properties. > A comparison with two other field actuation pumps at comparable length scales is also presented. > Our pump produces higher output at lower power supplies and magnetic field compared to the other two pumps.

  17. Characterization of a ferrofluid-based thermomagnetic pump for microfluidic applications

    International Nuclear Information System (INIS)

    We experimentally characterize the performance of a miniature thermomagnetic pump, where suitably imposed temperature and magnetic field gradients are used to drive ferrofluid in a 2 mm diameter glass capillary tube, without application of any external pressure gradient. Such a pump can operate in a hermetically sealed micro electromechanical system configuration without any moving part, and is thus capable of handling microfluidic samples with little risk of contamination. In the experiment, the ferrofluid in the capillary is exposed to a magnetic field using a solenoid; a small resistive heater wrapped on the tube wall is used to create temperature gradient in such a way that the Kelvin body force in the medium produces a net unbalanced axial component. This causes a thermomagnetic pumping action, transporting the ferrofluid in the capillary tube from the colder end to the warmer end. Performance of the thermomagnetic pump is investigated experimentally to characterize the pump pressure head and discharge under different working conditions, namely, the magnetic field strength, heating power, and ferrofluid properties. A comparison with two other field actuation pumps at comparable length scales is also presented. The pump produces higher output at lower power supplies and magnetic field compared to the other two pumps. - Highlights: → Operation of a miniature thermomagnetic pump is demonstrated and its performance is characterized. → Performance of the thermomagnetic pump is investigated experimentally to characterize the pump pressure head. → The discharge occurs under different working conditions, namely, the magnetic field strength, heating power, and ferrofluid properties. → A comparison with two other field actuation pumps at comparable length scales is also presented. → Our pump produces higher output at lower power supplies and magnetic field compared to the other two pumps.

  18. Progress and challenges in electrically pumped GaN-based VCSELs

    Science.gov (United States)

    Haglund, A.; Hashemi, E.; Bengtsson, J.; Gustavsson, J.; Stattin, M.; Calciati, M.; Goano, M.

    2016-04-01

    ABSTRACT The Vertical-Cavity Surface-Emitting Laser (VCSEL) is an established optical source in short-distance optical communication links, computer mice and tailored infrared power heating systems. Its low power consumption, easy integration into two-dimensional arrays, and low-cost manufacturing also make this type of semiconductor laser suitable for application in areas such as high-resolution printing, medical applications, and general lighting. However, these applications require emission wavelengths in the blue-UV instead of the established infrared regime, which can be achieved by using GaN-based instead of GaAs-based materials. The development of GaN-based VCSELs is challenging, but during recent years several groups have managed to demonstrate electrically pumped GaN-based VCSELs with close to 1 mW of optical output power and threshold current densities between 3-16 kA/cm2. The performance is limited by challenges such as achieving high-reflectivity mirrors, vertical and lateral carrier confinement, efficient lateral current spreading, accurate cavity length control and lateral optical mode confinement. This paper summarizes different strategies to solve these issues in electrically pumped GaN-VCSELs together with state-of-the-art results. We will highlight our work on combined transverse current and optical mode confinement, where we show that many structures used for current confinement result in unintentionally optically anti-guided resonators. Such resonators can have a very high optical loss, which easily doubles the threshold gain for lasing. We will also present an alternative to the use of distributed Bragg reflectors as high-reflectivity mirrors, namely TiO2/air high contrast gratings (HCGs). Fabricated HCGs of this type show a high reflectivity (>95%) over a 25 nm wavelength span.

  19. REMOTE CONTROLLING OF AN AGRICULTURAL PUMP SYSTEM BASED ON THE DUAL TONE MULTI-FREQUENCY (DTMF TECHNIQUE

    Directory of Open Access Journals (Sweden)

    BEZA N. GETU

    2015-10-01

    Full Text Available In modern days, as a result of advances in technology, human beings are interested to remotely control different systems and applications. In this work, telephone signalling technique using Dual Tone Multi-Frequency (DTMF signalling, is used to control switching of electrical loads such as agricultural pumps located in remote areas. A DTMF tone command sent from a transmitting fixed or mobile phone terminal will be used to SWITCH ON/OFF the motors used to pump water for agricultural fields. A processing electronic system at the receiving side is designed to interpret the tone commands and sends an appropriate signal to the motor driving circuit to complete the pump switching states. In the design methodology, it is possible to control several water pumps distributed in a certain agricultural site, however, in this work we considered four pumps and the paper presents the complete electronic design and simulation results at the different stages of the design. The electronic design is based on discrete passive and active electronic components and the system is tested and simulated using Multism program. The results of the simulation show that the design is capable of controlling the switching state of the motors. For a certain DTMF command, it is possible to switch ON/OFF a specific motor pump or all of the four motors.

  20. Insulin pumps.

    Science.gov (United States)

    Pickup, J

    2011-02-01

    The last year has seen a continued uptake of insulin pump therapy in most countries. The USA is still a leader in pump use, with probably some 40% of type 1 diabetic patients on continuous subcutaneous insulin infusion (CSII), but the large variation in usage within Europe remains, with relatively high use (> 15%) in, for example, Norway, Austria, Germany and Sweden and low use (companies or funding from national health services, the availability of sufficient diabetes nurse educators and dietitians trained in pump procedures, and clear referral pathways for the pump candidate from general practitioner or general hospital to specialist pump centre. There are now several comprehensive national guidelines on CSII use (see ATTD Yearbook 2009) but more work needs to be done in unifying uptake and ensuring all those who can benefit do so. Technology developments recently include increasing use of pumps with continuous glucose monitoring (CGM) connectivity (see elsewhere in this volume) and the emergence of numerous manufacturers developing so-called 'patch pumps', often for the type 2 diabetes market. Interestingly, the evidence base for CSII in this group is not well established, and for this reason the selected papers on CSII in this section include several in this area. The use of CSII in diabetic pregnancy is a long-established practice, in spite of the lack of evidence that it is superior to multiple daily injections (MDI), and few randomised controlled trials have been done in recent years. Several papers in this field this year continue the debate about the usefulness of CSII in diabetic pregnancy and are reviewed here. It is pleasing to see more research on the psychosocial aspects of CSII during the year, both from the point of view of how psychological beliefs influence outcomes on CSII (is there a type of patient who does particularly well or poorly on CSII?) and how CSII affects psychological factors like mood, behaviour and quality of life. Quality of

  1. 超高层建筑空调二次泵水系统运行分析%Study on the Design of Chilled Water System With Primary-secondary Pumps in Super High-rise

    Institute of Scientific and Technical Information of China (English)

    方伟

    2014-01-01

    本文主要阐述了超高层建筑空调二次泵水系统的原理、盈亏管的设置及系统的运行控制策略,并给出了实际工程中超高层建筑空调二次泵水系统遇到的常见问题及解决方式,旨在为空调二次泵水系统设计提供参考。%This paper provides main points of the primary-secondary pumps system in super high-rise, the design of the profit and loss tube, and the ways of the primary-secondary pumps system control. This paper also provides several solu-tions of the primary-secondary pumps problems in the project commissioning , in order to provide a reference design of air condition Primary-secondary Pumps system.

  2. Research on Three-Dimensional Unsteady Turbulent Flow in Multistage Centrifugal Pump and Performance Prediction Based on CFD

    OpenAIRE

    Zhi-jian Wang; Jian-she Zheng; Lu-lu Li; Shuai Luo

    2013-01-01

    The three-dimensional flow physical model of any stage of the 20BZ4 multistage centrifugal pump is built which includes inlet region, impeller flow region, guide-vane flow region and exit region. The three-dimensional unsteady turbulent flow numerical model is created based on Navier-Stoke solver and standard k-ε turbulent equations. The method of multireference frame (MRF) and SIMPLE algorithm are used to simulate the flow in multistage centrifugal pump based on FLUENT software. The distribu...

  3. Virtual Training System for Hydraulic Pump Cart Based on Virtual Reality

    Directory of Open Access Journals (Sweden)

    Wusha Huang

    2013-08-01

    Full Text Available This paper dissertates the application of Virtual Reality Technology in the training process. Virtual training system has more advantages than traditional training system. The design of virtual training system based on PTC DIVISION Mockup software, position tracker and 3-D mouse is proposed. The system is divided into two parts: directing part and operating part. Collision detection is discussed to improve the sense of reality in the virtual environment .This system is applied to the training process of hydraulic pump cart’s assembly and disassembly. More immersive training effect is obtained in this system. The goal of reducing training costs and improving the efficiency of training can be achieved in the virtual training system.  

  4. Vibration Signal Analysis of Main Coolant Pump Flywheel Based on Hilbert-Huang Transform

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Meiru; Xia, Hong; Yang, Yang [Harbin Engineering University, Harbin (China)

    2014-08-15

    In this paper, a 3D model for the dynamic analysis of flywheel based on finite element method is presented. The static structure analysis for the model provides stress and strain distribution cloud charts. The modal analysis provides the basis of dynamic analysis due to its ability to obtain the natural frequencies and the vibration-made vectors of the first 10 orders. The results show the main faults are attrition and crack that also indicated the locations and patterns of faults. Fault dynamic simulation has been performed to gain the vibration signals of flywheel under different faults' condition. In this paper, we attempt to present an algorithm for the application of Hilbert-Huang transform (HHT) for the analysis of flywheel vibration. This simulation indicated that the proposed flywheel vibration signal analysis method performs well, so that the method can be used for the detection of attrition and crack fault diagnosis in reactor main coolant pump.

  5. Validation of a PC based program for single stage absorption heat pump. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Zaltash, A.; Ally, M.R.

    1991-09-01

    An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

  6. Validation of a PC based program for single stage absorption heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Zaltash, A.; Ally, M.R.

    1991-09-01

    An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

  7. Workplace-based assessment in a primary-care setting.

    Science.gov (United States)

    Hecker, Kent G; Norris, Jill; Coe, Jason B

    2012-01-01

    Workplace-based assessment (WBA) is the process of directly observing students' work within a clinical setting, assessing their performance, and providing specific, goal oriented feedback. Assessment methods used for workplace-based assessment include tools developed for clinical interaction (e.g., the mini clinical evaluation exercise [mini-CEX]), for procedural or technical skills (e.g., the direct observation of procedural skills [DOPS]), and multi-source feedback tools to assess interpersonal and technical skills. While several of these assessment methods are being adopted by veterinary schools to evaluate students' progress through their clinical rotations, there is little reported at this time about their utility and effectiveness within the veterinary context. This article provides an introduction to the use of these tools and offers guidance in selecting appropriate methods for assessment in the primary health care setting. PMID:22951458

  8. Simulation Based Assessment of Heat Pumping Potential in Non-Residential Buildings – Part 1: Modeling

    OpenAIRE

    Bertagnolio, Stéphane; Stabat, Pascal; Soccal, Benjamin; Gendebien, Samuel; Andre, Philippe

    2010-01-01

    1 Introduction A solution to reduce the energy consumption in office and health care buildings consist in better exploiting the potential of the heat pump technology. This can be done by recovering heat at the condenser when the chiller is used to produce cold (simultaneous heating and cooling demands) or by using the chiller in heat pump mode (non-simultaneous heating and cooling demands). Both strategies appear particularly feasible when cooling and heating needs and the heat pump techno...

  9. Advanced high-power optical parametric oscillators synchronously pumped by ultrafast fibre-based sources

    OpenAIRE

    Kienle, Florian

    2012-01-01

    This thesis is concerned with investigating the generation of ultra short, tunable pulses at high average power and / or high pulse energy using synchronously pumped optical parametric oscillators (OPO) and appropriate power-scalable fibre-amplifier pump sources. Two types of pump sources with average powers up to ? 100W are considered: (1) a picosecond, all-fiberised, high-power, variable-repetition-rate, Yb:fibre-amplified, gain-switched laser diode system and (2) a femtosecond, high-power,...

  10. Dynamic analysis of the pump system based on MOC–CFD coupled method

    International Nuclear Information System (INIS)

    Highlights: • MOC–CFD coupled method was proposed to get the pump internal and external characteristics. • The coupled strategy and procedure were explained. • Some typical simulation cases were made for different factors. • The pump head deviation grows with the severity of the transient. • Valve closure law in linear and longer pipeline will cause higher pump head deviation. - Abstract: The dynamic characteristics of pump response to transient events were investigated by combining the Method of Characteristic (MOC) and Computational Fluid Dynamics (CFD) together. In a typical pump–pipeline–valve system, similar to the reactor system, the pump is treated as three-dimensional CFD model using Fluent code, whereas the rest is represented by one-dimensional components using MOC. A description of the coupling theory and procedure ensuring proper communication within the two codes is given. Several transient flow operations have been carried out. In the initial steady-state simulation, the coupled method could accurately find the operating condition of the pump when the valve is fully open. When the valve is closed rapidly, preliminary comparative calculations demonstrate that the coupled method is efficient in simulating the dynamic behavior of the pump and capable of getting detailed fluid field evolutions inside the pump. Deviation between the dynamic pump head and the value given by the steady-state curve at the same instantaneous flow-rate was established, and the cause of the deviation was further explained by the comparison of pump internal and external characteristics. Furthermore, it was found that the deviation grows with the severity of the transient. In addition, the effects of valve closure laws and pipe length on the pump dynamic performances were evaluated. All the results showed that MOC–CFD is an efficient and promising way for simulating the interaction between pump model and piping system

  11. Magnetocaloric heat-pump cycles based on the AF-F transition in Fe-Rh alloys

    Energy Technology Data Exchange (ETDEWEB)

    Annaorazov, M.P. E-mail: annaoraz@bahcesehir.edu.trannaoraz@hotmail.com; Uenal, M.; Nikitin, S.A.; Tyurin, A.L.; Asatryan, K.A

    2002-10-01

    The proposal involves a heat-pumping scheme based upon the first-order antiferromagnetism-ferromagnetism transition in FeRh alloy. Using the model S-T diagram for this alloy, the heat-pump cycles, are drawn up based on the transition latent heat absorption and emission when the transition is induced by applying magnetic field. The calculated values of heat coefficient {phi} for the cycles are {approx}39 at {delta}T=5 K and {approx}30 at {delta}T=10 K, where {delta}T is the difference between the temperature surrounding and that of the heat receiver. These values are achieved using the comparatively low magnetic fields of {approx}2x10{sup 6} A m{sup -1}. The high values of {phi}, together with high value of cooling capacity, make it possible to consider Fe-Rh alloys as an effective magnetic heat-pump working body near the room temperature.

  12. The pipeline oil pumping engineering based on the Plant Wide Control technology

    OpenAIRE

    Starikov, Dmitry Pavlovich; Rybakov, Evgeniy Aleksandrovich; Gromakov, Evgeny Ivanovich

    2015-01-01

    This article provides recommendations for the use technology Plant Wide Control to control the pumping of oil through the pipeline. The proposed engineering using pipeline management in general (Pipe Wide Control) will reduce the loss of electric power at the expense of the balance of pumping stations located along the pipeline route.

  13. Development of RCNP polarized He-3 ion source based on electron pumping

    NARCIS (Netherlands)

    Yamagata, T; Tanaka, M; Yonehara, K; Arimoto, Y; Takeuchi, T; Fujiwara, M; Plis, YA; Anderson, LW; Morgenstern, R

    1998-01-01

    We constructed a new polarized He-3 ion source in order to establish a method of principle of "electron pumping" and experimentally prove its validity. Electron pumping utilizes multiple electron capture and stripping collisions of He-3(+) with rubidium atoms whose vapor thickness is much thicker th

  14. STUDY ON POWER SPARE COEFFICIENT OF ELECTRICAL MOTOR IN LARGE PUMP STATION BASED ON RELIABILITY

    Institute of Scientific and Technical Information of China (English)

    Qiu Baoyun; Huang Jiyan; Yuan Shouqi

    2004-01-01

    Characters of head of low head pump station and the pump shaft power are analyzed. Influence of each single factor on pump shaft power is expressed as change of specific shaft power (non-dimensional) and the probability density function is determined. Influences of multiple factors on pump shaft power are analyzed. Method of calculating none over-loaded probability of motor by integration by successive reductions is put forward and then relation between power spare coefficient and none over-loaded reliability of electric motor is established. Influences of all factors on pump shaft power being considered completely; power spare coefficients of motor are calculated in three kinds of heads (changing and unchanging), two kinds of dirty-out conditions. Electrical motor power spare coefficients should be chosen as 1.20~1.44, 1.11~1.19, 1.09~1.14 respectively when pump heads are 4, 7, 9.5 m. The results mean much to reasonable choose of electrical motors in large pump stations, increasing reliability of pump units and saving equipment investment.

  15. Efficacy of Intra-aortic Balloon Pump before versus after Primary Percutaneous Coronary Intervention in Patients with Cardiogenic Shock from ST-elevation Myocardial Infarction

    Science.gov (United States)

    Yuan, Lin; Nie, Shao-Ping

    2016-01-01

    Background: Previous studies showed that patients with cardiogenic shock (CS) from ST-elevation acute myocardial infarction (STEMI) supported by intra-aortic balloon pump (IABP) before primary percutaneous coronary intervention (PCI) decreased the risk of in-hospital mortality than patients who received IABP after PCI. However, little evidence is available on the optimal order of IABP insertion and primary PCI. The aim of this study was to investigate the impact of the sequence of IABP support and PCI and its association with major adverse cardiac and cerebrovascular events (MACCEs). Methods: Data were obtained from 218 consecutive patients with CS due to STEMI in Beijing Anzhen Hospital between 2008 and 2014, who were treated with IABP and PCI. The patients were divided into two groups: Group A in whom IABP received before PCI (n = 106) and Group B in whom IABP received after PCI (n = 112). We evaluated the myocardial perfusion using myocardial blush grade and resolution of ST-segment elevation. The primary endpoint was 12-month risk of MACCE. Results: Most baseline characteristics were similar in patients between the two groups. However, patients received IABP before PCI were associated with a delay of door-to-balloon time (DBT) and higher troponin I level (P 0.05). In addition, risk of all-cause mortality, bleeding, and acute kidney injury (AKI) was similar between two groups (P > 0.05). Multivariate analysis showed that DBT (odds ratio [OR] 2.5, 95% confidence interval [CI] 1.1–4.8, P = 0.04), IABP support after PCI (OR 5.7, 95% CI 2.7–8.4, P = 0.01), and AKI (OR 7.4, 95% CI 4.9–10.8, P = 0.01) were the independent predictors of mortality at 12-month follow-up. Conclusions: Early IABP insertion before primary PCI is associated with improved myocardial perfusion although DBT increases. IABP support before PCI does not confer a 12-month clinical benefit when used for STEMI with CS. PMID:27270533

  16. Efficacy of Intra-aortic Balloon Pump before versus after Primary Percutaneous Coronary Intervention in Patients with Cardiogenic Shock from ST-elevation Myocardial Infarction

    Institute of Scientific and Technical Information of China (English)

    Lin Yuan; Shao-Ping Nie

    2016-01-01

    Background:Previous studies showed that patients with cardiogenic shock (CS) from ST-elevation acute myocardial infarction (STEMI) supported by intra-aortic balloon pump (IABP) before primary percutaneous coronary intervention (PCI) decreased the risk of in-hospital mortality than patients who received IABP after PCI.However,little evidence is available on the optimal order of IABP insertion and primary PCI.The aim of this study was to investigate the impact of the sequence of IABP support and PCI and its association with major adverse cardiac and cerebrovascular events (MACCEs).Methods:Data were obtained from 218 consecutive patients with CS due to STEMI in Beijing Anzhen Hospital between 2008 and 2014,who were treated with IABP and PCI.The patients were divided into two groups:Group A in whom IABP received before PCI (n =106)and Group B in whom IABP received after PCI (n =112).We evaluated the myocardial perfusion using myocardial blush grade and resolution of ST-segment elevation.The primary endpoint was 12-month risk of MACCE.Results:Most baseline characteristics were similar in patients between the two groups.However,patients received IABP before PCI were associated with a delay of door-to-balloon time (DBT) and higher troponin Ⅰ level (P < 0.05).However,myocardial perfusion was significantly improved in patients treated with IABP before PCI (P < 0.05).Overall,IABP support before PCI was not associated with significantly lower risk of MACCE (P > 0.05).In addition,risk of all-cause mortality,bleeding,and acute kidney injury (AKI)was similar between two groups (P > 0.05).Multivariate analysis showed that DBT (odds ratio [OR] 2.5,95% confidence interval [CI]1.1-4.8,P=0.04),IABP support after PCI (OR 5.7,95% CI 2.7-8.4,P=0.01),and AKI (OR 7.4,95% CI 4.9-10.8,P=0.01) were the independent predictors of mortality at 12-month follow-up.Conclusions:Early IABP insertion before primary PCI is associated with improved myocardial perfusion although DBT

  17. Wavelength stabilizer based on dual fiber Bragg gratings for 980nm Mini-uncooled pump laser

    Science.gov (United States)

    Hu, Shuangshuang; Li, Yi; Jiang, Qunjie; Wu, Bin; Yu, Xiaojing; Wang, Haifang

    2008-12-01

    High power 980nm pump lasers are the key components in optical fiber amplifier. Wavelength stability for 980nm Miniuncooled pump laser is required to maintain the amplifier's efficiency throughout its lifetime. In this paper, a new type of wavelength stabilizer for uncooled pump laser which utilizes two fiber Bragg gratings (FBGs) matched in wavelength, bandwidth, and reflectivity is presented. The characteristics of transmissivity and reflectivity for the dual FBGs stabilized 980nm pump laser are theoretically modeled and experimentally studied. The results show that the output spectral characteristics of the uncooled pump laser with the dual FBGs have been greatly improved. The laser module can work steadily over a wide temperature range from 0°C to 70°C, with 0.2nm wavelength shift, along with more than 45dB side mode suppression ratio, and less than 1.57nm spectral bandwidth.

  18. Towards loss compensated and lasing terahertz metamaterials based on optically pumped graphene

    CERN Document Server

    Weis, Peter; Rahm, Marco

    2013-01-01

    It is evidenced by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. In a first step, the complex conductivity of graphene under optical pumping is calculated and the proper conditions for terahertz amplification in single layer graphene are determined. It is shown that amplification in graphene occurs for temperatures up to room temperature and for moderate pump intensities when pumped at a telecommunication wavelength $\\lambda=1.5~\\mathrm{\\mu m}$. Furthermore, the amplification properties of graphene are evaluated and discussed at a temperature as low as $T=77~\\mathrm{K}$ and a pump intensity $I=300~\\mathrm{mW/mm^2}$ to investigate the coupling between graphene and a plasmonic split ring resonator (SRR) metamaterial. The contributions of ohmic and dielectric loss mechanisms are studied by full wave simulations. As a result, it is found that the loss of a split-ring resonator metamaterial can be compensated by optically stimulat...

  19. A new ejector heat exchanger based on an ejector heat pump and a water-to-water heat exchanger

    International Nuclear Information System (INIS)

    Highlights: • EHE is based on the reverse Carnot cycle and current heat transfer mechanisms. • EHE can decrease the return water temperature in the PHN to 35 °C. • EHE can increase the heating capacity of the existed PHN by approximately 43%. • The return water temperature in the PHN is much lower than that in the SHN. • EHE has a simpler structure, lower manufacture cost, and better regulation characteristics. - Abstract: As urban construction has been developing rapidly in China, urban heating load has been increasing continually. Heating capacity of the existed primary heating network (PHN) cannot meet district heating requirements of most metropolises in northern China. A new type of ejector heat exchanger (EHE) based on an ejector heat pump and a water-to-water heat exchanger (WWHE) was presented to increase the heating capacity of the existed PHN, and the EHE was also analyzed in terms of laws of thermodynamics. A new parameter, the exergy distribution ratio (EDR), is introduced, which is adopted to analyze regulation characteristics of the EHE. We find that the EHE shows better performance when EDR ranges from 44% to 63%. EHE can decrease the temperature of return water in the PHN to 35 °C, therefore, this can increase the heating capacity of existed PHN by about 43%. The return water with lower temperature in the PHN could recover more low-grade waste heat in industrial systems. Because of its smaller volume and lower investment, EHEs could be applied more appropriately in district heating systems for long-distance heating and waste heat district heating systems

  20. Passive harmonically mode-locked fiber laser with low pumping power based on a graphene saturable absorber

    International Nuclear Information System (INIS)

    A passive harmonically mode-locked fiber laser based on a graphene saturable absorber has been experimentally demonstrated. Under different pump powers and different polarization states of the cavity, lower and higher order harmonic mode-locking has been obtained. The 46th scalable harmonic was achieved which corresponded to a repetition rate of 0.49 GHz and could be observed at a relative lower pump power of 162.4 mW. We deduce that the existence, position and stability of the relatively strong continuous wave components in the spectrum of solitons play an important role in the formation of higher order harmonic mode-locking

  1. The KALPUREX-process – A new vacuum pumping process for exhaust gases in fusion power plants

    International Nuclear Information System (INIS)

    Highlights: • A new vacuum pumping process for fusion power plants has been developed and is presented in this paper. • This process works continuously and non-cryogenic what leads to a strong reduction of the tritium inventory in the fuel cycle. • This pumping process is based on the use of a liquid metal (mercury) as working fluid and is called KALPUREX process. • The KALPUREX process is the technical realization of the DIR concept using a set of three vacuum pumps (metal foil pump/diffusion pump/liquid ring pump). • This paper discusses the arrangement of the pumps and also the required infrastructure for operation. - Abstract: The Karlsruhe Institute of Technology (KIT) is developing a continuously working and non-cryogenic pumping solution for torus exhaust pumping of a demonstration power plant (DEMO) including Direct Internal Recycling (DIR). This full pumping system consists of three pumps, namely a metal foil pump for gas separation, a linear diffusion pump as primary pump and a liquid ring pump as backing pump. The latter two pumps apply mercury as working fluid due to its perfect tritium compatibility. This asks for a baffle system on both sides of the pumping train to control working fluid vapour and to avoid any mercury propagation in the machine. In this paper, the arrangement of all torus pumps required for a power plant reactor as well as the corresponding infrastructure and its effect on the DEMO machine design is presented and discussed. The full pumping process is called ‘Karlsruhe liquid metal based pumping process for fusion reactor exhaust gases’ (KALPUREX process, patent pending)

  2. Development of a Compact, Efficient Cooling Pump for Space Suit Life Support Systems

    Science.gov (United States)

    van Boeyen, Roger; Reeh, Jonathan; Trevino, Luis

    2009-01-01

    A compact, low-power electrochemically-driven fluid cooling pump is currently being developed by Lynntech, Inc. With no electric motor and minimal lightweight components, the pump is significantly lighter than conventional rotodynamic and displacement pumps. Reliability and robustness is achieved with the absence of rotating or moving components (apart from the bellows). By employing sulfonated polystyrene-based proton exchange membranes, rather than conventional Nafion membranes, a significant reduction in the actuator power consumption was demonstrated. Lynntech also demonstrated that these membranes possess the necessary mechanical strength, durability, and temperature range for long life space operation. The preliminary design for a Phase II prototype pump compares very favorably to the fluid cooling pumps currently used in space suit primary life support systems (PLSSs). Characteristics of the electrochemically-driven pump are described and the benefits of the technology as a replacement for electric motor pumps in mechanically pumped single-phase fluid loops is discussed.

  3. Accuracy of a New Patch Pump Based on a Microelectromechanical System (MEMS) Compared to Other Commercially Available Insulin Pumps: Results of the First In Vitro and In Vivo Studies

    OpenAIRE

    Borot, Sophie; Franc, Sylvia; Cristante, Justine; Penfornis, Alfred; Benhamou, Pierre-Yves; Guerci, Bruno; Hanaire, Hélène; Renard, Eric; Reznik, Yves; Simon, Chantal; Charpentier, Guillaume

    2014-01-01

    The JewelPUMP™ (JP) is a new patch pump based on a microelectromechanical system that operates without any plunger. The study aimed to evaluate the infusion accuracy of the JP in vitro and in vivo. For the in vitro studies, commercially available pumps meeting the ISO standard were compared to the JP: the MiniMed® Paradigm® 712 (MP), Accu-Chek® Combo (AC), OmniPod® (OP), Animas® Vibe™ (AN). Pump accuracy was measured over 24 hours using a continuous microweighing method, at 0.1 and 1 IU/h bas...

  4. Threshold values of autoresonant pumping

    OpenAIRE

    Kiselev, O. M.

    2013-01-01

    There exists stable growing solution of primary resonant equation for a autoresonant pumping with decreasing amplitude. The primary term of asymptotics is $O(\\sqrt{t})$ and does not depend on order of the force from some interval. We point to the interval for the amplitude of the pumping for which the growing stable solution exists.

  5. Silicon-Based Chemical Motors: An Efficient Pump for Triggering and Guiding Fluid Motion Using Visible Light.

    Science.gov (United States)

    Esplandiu, Maria J; Farniya, Ali Afshar; Bachtold, Adrian

    2015-11-24

    We report a simple yet highly efficient chemical motor that can be controlled with visible light. The motor made from a noble metal and doped silicon acts as a pump, which is driven through a light-activated catalytic reaction process. We show that the actuation is based on electro-osmosis with the electric field generated by chemical reactions at the metal and silicon surfaces, whereas the contribution of diffusio-osmosis to the actuation is negligible. Surprisingly, the pump can be operated using water as fuel. This is possible because of the large ζ-potential of silicon, which makes the electro-osmotic fluid motion sizable even though the electric field generated by the reaction is weak. The electro-hydrodynamic process is greatly amplified with the addition of reactive species, such as hydrogen peroxide, which generates higher electric fields. Another remarkable finding is the tunability of silicon-based pumps. That is, it is possible to control the speed of the fluid with light. We take advantage of this property to manipulate the spatial distribution of colloidal microparticles in the liquid and to pattern colloidal microparticle structures at specific locations on a wafer surface. Silicon-based pumps hold great promise for controlled mass transport in fluids. PMID:26349036

  6. Development of Stepper motor based Two DOF Robotic Arm Transferring Liquid using Peristaltic Pump

    Directory of Open Access Journals (Sweden)

    Padma Thiagarajan

    2013-02-01

    Full Text Available The aim of this work is to transfer liquid contents from one micro cell to another using two stepper motors and a peristaltic pump. There are two objectives here. One is to develop a low cost roboticarm using stepper motors. The second objective is the control and calibration of the peristaltic pump. All parts are controlled and operated by their respective microcontrollers. Fulfillment of both the objectives leads to an integrated system to transfer liquids from one cell to another. The end effecter of the robotic arm is connected to the peristaltic pump. The pump has two pipes connected to it. Through one pipe it takes in the liquid and through the other pipe it delivers the liquid into the second cell. After transferring one sample of liquid, the arm moves to a cleaning module where the end effecter is cleaned to avoid cross contamination. The robotic arm is built using stepper motors and controlled using Atmega32 microcontroller whereas the peristaltic pump is controlled and calibrated using 8051 microcontroller. The pumping is done with the help of DC motors. As a result, the working of the robotic arm and theperistaltic pump is verified experimentally.

  7. Development of a pump-turbine runner based on multiobjective optimization

    International Nuclear Information System (INIS)

    As a key component of reversible pump-turbine unit, pump-turbine runner rotates at pump or turbine direction according to the demand of power grid, so higher efficiencies under both operating modes have great importance for energy saving. In the present paper, a multiobjective optimization design strategy, which includes 3D inverse design method, CFD calculations, response surface method (RSM) and multiobjective genetic algorithm (MOGA), is introduced to develop a model pump-turbine runner for middle-high head pumped storage plant. Parameters that controlling blade shape, such as blade loading and blade lean angle at high pressure side are chosen as input parameters, while runner efficiencies under both pump and turbine modes are selected as objective functions. In order to validate the availability of the optimization design system, one runner configuration from Pareto front is manufactured for experimental research. Test results show that the highest unit efficiency is 91.0% under turbine mode and 90.8% under pump mode for the designed runner, of which prototype efficiencies are 93.88% and 93.27% respectively. Viscous CFD calculations for full passage model are also conducted, which aim at finding out the hydraulic improvement from internal flow analyses

  8. [Numerical assessment of impeller features of centrifugal blood pump based on fast hemolysis approximation model].

    Science.gov (United States)

    Shou, Chen; Guo, Yongjun; Su, Lei; Li, Yongqian

    2014-12-01

    The impeller profile, which is one of the most important factors, determines the creation of shear stress which leads to blood hemolysis in the internal flow of centrifugal blood pump. The investigation of the internal flow field in centrifugal blood pump and the estimation of the hemolysis within different impeller profiles will provide information to improve the performance of centrifugal blood pump. The SST kappa-omega with low Reynolds correction was used in our laboratory to study the internal flow fields for four kinds of impellers of centrifugal blood pump. The flow fields included distributions of pressure field, velocity field and shear stress field. In addition, a fast numerical hemolysis approximation was adopted to calculate the normalized index of hemolysis (NIH). The results indicated that the pressure field distribution in all kinds of blood pump were reasonable, but for the log spiral impeller pump, the vortex and backflow were much lower than those of the other pumps, and the high shear stress zone was just about 0.004%, and the NIH was 0.0089. PMID:25868241

  9. Light: an experiments based learning approach with primary school children

    Science.gov (United States)

    Abreu, Cátia; Noversa, Silvana; Varela, Paulo; Costa, Manuel F.

    2014-07-01

    A pedagogical intervention project was carried out at a primary school in the municipality of Vila Verde, Braga in Portugal. In a class of the 3rd grade, composed of 16 students, a practice of inquiry-based science teaching was implemented, addressing the curricular topic "Light Experiments". Various experimental activities were planned within this topic, including: What is light? How does light travel? Does light travel through every material? How is light reflected by a mirror? This project adopted an action research methodology and had as its main objectives: a) to promote a practical and experimental approach to the science component of the Environmental Studies curricular area; b) to describe the scientific meaning construction process inherent to the topics addressed in the classroom with the children, c) to assess the learning steps and children' achievements. Class diaries were prepared, based on field notes and audio recordings taken in the classroom. Through the analysis of the class diary concerning the topic "materials that let light travel through them" we intend to illustrate the process of construction of scientific meanings promoted in the classroom with our approach.

  10. Theoretical study of thermally driven heat pumps based on double organic rankine cycle

    OpenAIRE

    Demierre, Jonathan; Favrat, Daniel

    2013-01-01

    Part of: Thermally driven heat pumps for heating and cooling. – Ed.: Annett Kühn – Berlin: Universitätsverlag der TU Berlin, 2013 ISBN 978-3-7983-2686-6 (print) ISBN 978-3-7983-2596-8 (online) urn:nbn:de:kobv:83-opus4-39458 [http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-39458] This study deals with a type of thermally driven heat pumps that consists of a reverse Rankine heat pump cycle, the compressor of which is driven by the turbine of a supercritical Organi...

  11. The Impeller Improvement of the Centrifugal Pump Based on BVF Diagnostic Method

    OpenAIRE

    Xin Zhou; Yongxue Zhang; Zhongli Ji; Long Chen

    2014-01-01

    Selecting one IS 150-125-250 centrifugal pump as reference model, impeller with 3D blades has been designed using two-dimensional theory. Numerical simulations using Reynolds averaged N-S equations with a RNG k-ε two-equation turbulence model and log-law wall function are used to estimate the hydraulic performance of pump and obtain BVF distributions on impeller blade pressure surfaces and suction surfaces. The results show that, compared with IS150-125-250 pump, the designed one shows better...

  12. Observer based Model Identification of Heat Pumps in a Smart Grid

    DEFF Research Database (Denmark)

    Andersen, Palle; Pedersen, Tom S.; Nielsen, Kirsten M.

    2012-01-01

    . A part of a solution can be to take advantage of floor heat capacity in single-family houses using heat pumps.This large heat capacity makes it possible to move consumption without compromising the comfort of house residents. In a Danish research project a virtual power plant using centralized control...... of a large number of houses with heat pumps is established. In order to make the control algorithm a vital part is a dynamic model of each house. The model predicts the house indoor temperature when heat pump power and outdoor temperature is known. The model must be able to describe a large variety of heat...

  13. 33 CFR 183.524 - Fuel pumps.

    Science.gov (United States)

    2010-07-01

    ... diaphragm pump must not leak fuel from the pump if the primary diaphragm fails. (b) Each electrically operated fuel pump must not operate except when the engine is operating or when the engine is started. (c) If tested under § 183.590, each fuel pump, as installed in the boat, must not leak more than...

  14. Centrifugal pumps

    CERN Document Server

    Anderson, HH

    1981-01-01

    Centrifugal Pumps describes the whole range of the centrifugal pump (mixed flow and axial flow pumps are dealt with more briefly), with emphasis on the development of the boiler feed pump. Organized into 46 chapters, this book discusses the general hydrodynamic principles, performance, dimensions, type number, flow, and efficiency of centrifugal pumps. This text also explains the pumps performance; entry conditions and cavitation; speed and dimensions for a given duty; and losses. Some chapters further describe centrifugal pump mechanical design, installation, monitoring, and maintenance. The

  15. A heat pump driven and hollow fiber membrane-based liquid desiccant air dehumidification system: Modeling and experimental validation

    International Nuclear Information System (INIS)

    A compression heat pump driven and membrane-based liquid desiccant air dehumidification system is presented. The dehumidifier and the regenerator are made of two hollow fiber membrane bundles packed in two shells. Water vapor can permeate through these membranes effectively, while the liquid desiccant droplets are prevented from cross-over. Simultaneous heating and cooling of the salt solution are realized with a heat pump system to improve energy efficiency. In this research, the system is built up and a complete modeling is performed for the system. Heat and mass transfer processes in the membrane modules, as well as in the evaporator, the condenser, and other key components are modeled in detail. The whole model is validated by experiment. The performances of SDP (specific dehumidification power), dehumidification efficiency, EER (energy efficiency ratio) of heat pump, and the COP (coefficient of performance) of the system are investigated numerically and experimentally. The results show that the model can predict the system accurately. The dehumidification capabilities and the energy efficiencies of the system are high. Further, it performs well even under the harsh hot and humid South China weather conditions. - Highlights: • A membrane-based and heat pump driven air dehumidification system is proposed. • A real experimental set up is built and used to validate the model for the whole system. • Performance under design and varying operation conditions is investigated. • The system performs well even under harsh hot and humid conditions

  16. Cyanobacterial light-driven proton pump, gloeobacter rhodopsin: complementarity between rhodopsin-based energy production and photosynthesis.

    Directory of Open Access Journals (Sweden)

    Ah Reum Choi

    Full Text Available A homologue of type I rhodopsin was found in the unicellular Gloeobacter violaceus PCC7421, which is believed to be primitive because of the lack of thylakoids and peculiar morphology of phycobilisomes. The Gloeobacter rhodopsin (GR gene encodes a polypeptide of 298 amino acids. This gene is localized alone in the genome unlike cyanobacterium Anabaena opsin, which is clustered together with 14 kDa transducer gene. Amino acid sequence comparison of GR with other type I rhodopsin shows several conserved residues important for retinal binding and H+ pumping. In this study, the gene was expressed in Escherichia coli and bound all-trans retinal to form a pigment (λmax  = 544 nm at pH 7. The pKa of proton acceptor (Asp121 for the Schiff base, is approximately 5.9, so GR can translocate H+ under physiological conditions (pH 7.4. In order to prove the functional activity in the cell, pumping activity was measured in the sphaeroplast membranes of E. coli and one of Gloeobacter whole cell. The efficient proton pumping and rapid photocycle of GR strongly suggests that Gloeobacter rhodopsin functions as a proton pumping in its natural environment, probably compensating the shortage of energy generated by chlorophyll-based photosynthesis without thylakoids.

  17. Design of ion-pump power supply control software system based on TCP/IP protocol

    International Nuclear Information System (INIS)

    This paper discuss a Ion-pump Power Supply control system making use of RS232 series bus and Intranet. The system's hardware VAC800 is composed of MSP430F149 mixed-signal processors produced by TI and UA7000A network model. MSP430F149 has advantages of ultra-low-power and high-integration. The Ion-pump Power Supply control system has the characteristics of strong function, simple structure, high reliability, strong resistance of noise, no peripheral chip, etc. Visual studio 2005 is used to design the system's software. The Ion-pump Power supplier control system can remotely monitor and control Ion-pump Power Suppliers. (authors)

  18. End-pumped coupling system based on large-aperture laser diode array

    International Nuclear Information System (INIS)

    In order to meet the pump power density requirements of room-temperature Yb: YAG laser amplifier, a coupling system of high contraction coefficient has been designed. Laser diode (LD) arrays of 80 kW output power are arranged to be spherical. Orthogonal cylindrical lenses and a hollow duct are used for pump-coupling according to luminescence properties of LD. The contraction coefficient is up to 86:1. Simulations show that the coupling efficiency of the coupling system depends weakly on the reflectivity of the reflectors of the hollow duct. The pump light can transport over a distance of at least 8.5 mm with its shape maintained. The coupling system can meet the requirements of the end-pumped room-temperature Yb: YAG slab amplifier. (authors)

  19. Development of Stepper motor based Two DOF Robotic Arm Transferring Liquid using Peristaltic Pump

    OpenAIRE

    Padma Thiagarajan; Sudha Ramasamy; Karthikesh.R; Manikandan.P

    2013-01-01

    The aim of this work is to transfer liquid contents from one micro cell to another using two stepper motors and a peristaltic pump. There are two objectives here. One is to develop a low cost roboticarm using stepper motors. The second objective is the control and calibration of the peristaltic pump. All parts are controlled and operated by their respective microcontrollers. Fulfillment of both the objectives leads to an integrated system to transfer liquids from one cell to another. The end ...

  20. Crystallization Analysis and Control of Ammonia-Based Air Source Absorption Heat Pump in Cold Regions

    OpenAIRE

    Wu, Wei; Wang, Baolong; Shi, Wenxing; Li, Xianting

    2013-01-01

    Energy consumption of heating and domestic hot water is very high and will keep increasing. Air source absorption heat pump (ASAHP) was proposed to overcome the problems of low energy efficiency and high air pollution existing in boiler systems, as well as the problem of bad performance under low ambient temperatures for electrical heat pumps. In order to investigate the crystallization possibility of ammonia-salt ASAHP, crystallization margin (evaluated by solution mass concentration) at gen...

  1. A case-based reasoning approach for estimating the costs of pump station projects

    OpenAIRE

    Marzouk, Mohamed M.; Rasha M. Ahmed

    2011-01-01

    The effective estimation of costs is crucial to the success of construction projects. Cost estimates are used to evaluate, approve and/or fund projects. Organizations use some form of classification system to identify the various types of estimates that may be prepared during the lifecycle of a project. This research presents a parametric-cost model for pump station projects. Fourteen factors have been identified as important to the influence of the cost of pump station projects. A data set t...

  2. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis

    OpenAIRE

    Wang, Guorong; Zhong, Lin; He, Xia; Lei, Zhongqing; Hu, Gang; Li, Rong; Wang, Yunhai

    2015-01-01

    The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening...

  3. Analysis on Energy Conversion of Screw Centrifugal Pump in Impeller Domain Based on Profile Lines

    OpenAIRE

    Hui Quan; Rennian Li; Qingmiao Su; Wei Han; Pengcheng Wang

    2013-01-01

    In order to study the power capability of impeller and energy conversion mechanism of screw centrifugal pump, the methods of theoretical analysis and numerical simulation by computational fluid dynamics theory (CFD) were adopted, specifically discussing the conditions of internal flow such as velocity, pressure, and concentration. When the medium is sand-water two-phase flow and dividing the rim of the lines and wheel lines of screw centrifugal pump to segments to analyze energy conversion ca...

  4. A research on an energy-saving software for pumping units based on FNN intelligent control

    Institute of Scientific and Technical Information of China (English)

    丁宝; 齐维贵; 王凤平

    2004-01-01

    An energy-saving scheme for pumping units via intermission start-stop performance is proposed. Because of the complexity of the oil extraction process, Fuzzy Neural Network (FNN) intelligent control is adopted. The structure of the Takagi-Sugeno (T-S) fuzzy neural network model is introduced and modified. FNNs are trained with sample information from oil fields and expert knowledge. Finally, pumping unit energy-saving FNN software, which cuts down power costs substantially, is presented.

  5. Electrically pumped near-ultraviolet lasing from ZnO Nanowire Based Heterojunctions

    Science.gov (United States)

    Mu, Richard; Xu, Haiyang; Liu, Yichun

    2014-03-01

    ZnO with a band gap (3.37 eV) and an exciton binding energy (60 meV) is a promising material for ultraviolet (UV) light-emitting diodes (LEDs) and low-threshold lasing diodes. Much progress has been made recently to enhance band edge emission of ZnO nanowire (NW) structure through surface passivation and local surface plasmon enahncement with metal nanparticles. Efforts have been made to fabricate electrically pumped near-ultraviolet lasing devices with metal/insulator/semiconductor laser diode based on ZnO/MgO core/shell nanowires with and without metal nanoparticle presences. The nanowire diode shows higher emission intensity at relatively low operating current density compared with the planar device. The improved efficiency is attributed to enhanced exciton oscillator strength and superior carrier transport properties of single-crystalline ZnO nanowires, and effective surface passivation by MgO coating. Random laser action was confirmed by the calculation of quality factor and the real-time changes of lasing spectra. The results reveal that the MgO coating serves as electron blocking, hole supplying and surface passivation layer for the nanowire heterostructure. Other approaches will also be presented and discussed in the presentation. DMR-0423914, NSF-CREST HRD-0420516, and DOD W911NF-11-1-0156 and -13-1-0153.

  6. Continuous wave terahertz wave spectrometer based on diode laser pumping: potential applications in high resolution spectroscopy.

    Science.gov (United States)

    Tanabe, Tadao; Ragam, Srinivasa; Oyama, Yutaka

    2009-11-01

    We constructed a high resolution terahertz (THz) spectroscopic system with an automatic scanning control using a continuous wave (cw) THz wave generator based on difference frequency generation method by excitation of phonon-polariton mode in GaP. The pump and signals lasers were compact, tunable external cavity laser, and distributed feedback (DFB) lasers, respectively. The generated THz waves were tuned automatically by changing the temperature of the DFB laser using a system control. We present the water vapor transmission characteristics of the THz wave and also absorption spectrum of a white polyethylene in the frequency range of 1.97-2.45 THz. The spectroscopic measurements performed at an output power level of 2 nW, which was obtained with a 15-mm-long GaP crystal at 2 THz. The advantage of this cw THz spectrometer is wide frequency tuning range (0.7-4.42 THz) with an estimated linewidth of full width at quarter maximum <8 MHz and this system has a potential application in high resolution spectroscopy. PMID:19947715

  7. Energy-efficient miniature-scale heat pumping based on shape memory alloys

    Science.gov (United States)

    Ossmer, Hinnerk; Wendler, Frank; Gueltig, Marcel; Lambrecht, Franziska; Miyazaki, Shuichi; Kohl, Manfred

    2016-08-01

    Cooling and thermal management comprise a major part of global energy consumption. The by far most widespread cooling technology today is vapor compression, reaching rather high efficiencies, but promoting global warming due to the use of environmentally harmful refrigerants. For widespread emerging applications using microelectronics and micro-electro-mechanical systems, thermoelectrics is the most advanced technology, which however hardly reaches coefficients of performance (COP) above 2.0. Here, we introduce a new approach for energy-efficient heat pumping using the elastocaloric effect in shape memory alloys. This development is mainly targeted at applications on miniature scales, while larger scales are envisioned by massive parallelization. Base materials are cold-rolled textured Ti49.1Ni50.5Fe0.4 foils of 30 μm thickness showing an adiabatic temperature change of +20/‑16 K upon superelastic loading/unloading. Different demonstrator layouts consisting of mechanically coupled bridge structures with large surface-to-volume ratios are developed allowing for control by a single actuator as well as work recovery. Heat transfer times are in the order of 1 s, being orders of magnitude faster than for bulk geometries. Thus, first demonstrators achieve values of specific heating and cooling power of 4.5 and 2.9 W g‑1, respectively. A maximum temperature difference of 9.4 K between heat source and sink is reached within 2 min. Corresponding COP on the device level are 4.9 (heating) and 3.1 (cooling).

  8. Study on water lubricated bearings of high speed pump based on numerical simulation

    Science.gov (United States)

    Bai, Y. X.; Kong, F. Y.; Sun, J. R.; Yuan, X.

    2016-05-01

    A method is presented for calculating and analyzing the performance of water lubricated bearing of high speed pump under different structure. In present work, six kinds of bearings in different radial clearance(C), which are 0.02, 0.04, 0.06, 0.08, 0.10and0.12 respectively, under the same minimum water film thickness, have been designed. The models are built by CREO and numerical simulated by ansys. The main content of the present work is to analyze the relationship between the pressure and the load carrying capacity with different radial clearance(C) by ansys workbench based on Fluid-Solid coupling through ansys workbench.The stress deformations of bearings are also acquired through thermal-structure coupling. From the comparing result among the numerical analysis under the six different model of water lubricated bearing, the relationship between radial clearance(C) and load carrying capacity, as well as the deformation of bearing under different radial clearance(C), are obtained. Further, results indicates that, a proper selection of radial clearance(C) is essential to enhance the bearing performance.

  9. A Neural Network Based MPPT Technique Controller for Photovoltaic Pumping System

    Directory of Open Access Journals (Sweden)

    Mohammed Yaichi

    2014-03-01

    Full Text Available The article proposes a novel method using the artificial neural network (ANN for the improvement of the performances of a photovoltaic system composed of a photovoltaic (PV array, an inverter, a motor asynchronous and a centrifugal pump. For this type of system, different optimization strategies have been proposed to improve the over of the PV system efficiency, i.e. the PV generator is forced to operate at its maximum power point “MPPT”, generally, by the insertion of DC/DC boost converter between the photovoltaic array and the inverter. In this work we propose an approach, where optimization is realized without need adding a DC/DC converter to the chain, using field-oriented control through the monitoring of the voltage-fed inverter frequency. The motor is also ensured in all insolation conditions. A multilayer feed forward perception type NN is proposed for MPPT control, and the back-propagation algorithm is used for training. The performances of the drive with ANN-based MPPT are excellent. The maximum power point (MPP can be easily obtained to frequency-controlled drive.

  10. Numerical analysis of the internal flow field in screw centrifugal blood pump based on CFD

    Science.gov (United States)

    Han, W.; Han, B. X.; Y Wang, H.; Shen, Z. J.

    2013-12-01

    As to the impeller blood pump, the high speed of the impeller, the local high shear force of the flow field and the flow dead region are the main reasons for blood damage. The screw centrifugal pump can effectively alleviate the problems of the high speed and the high shear stress for the impeller. The softness and non-destructiveness during the transfer process can effectively reduce the extent of the damage. By using CFD software, the characteristics of internal flow are analyzed in the screw centrifugal pump by exploring the distribution rules of the velocity, pressure and shear deformation rate of the blood when it flows through the impeller and the destructive effects of spiral blades on blood. The results show that: the design of magnetic levitation solves the sealing problems; the design of regurgitation holes solves the problem of the flow dead zone; the magnetic levitated microcirculation screw centrifugal pump can effectively avoid the vortex, turbulence and high shear forces generated while the blood is flowing through the pump. Since the distribution rules in the velocity field, pressure field and shear deformation rate of the blood in the blood pump are comparatively uniform and the gradient change is comparatively small, the blood damage is effectively reduced.

  11. Erosion predictions of stock pump impellers based on liquid-solid two-phase fluid simulations

    International Nuclear Information System (INIS)

    Stock pumps cost 25 percent of total power consumption in a modern paper mill. Owing to the severe erosion of pump casing and impeller during operation, stock pump often results in efficiency drop and rising power consumption. A favourable prediction of the impeller wearing character can effective guide optimization design of stock pump impeller. Thereby it can reduce impeller wear and extend stock pump performance life. We simulated the three-dimensional unsteady solid-liquid two-phase flow characteristic in the hydraulic channel of a low specific speed stock pump with open and three blades impeller. The standard k- ε turbulent model and the pseudo-fluid model were adopted in simulation. Clearance between covers and impeller is taken into consideration in modelling, and pulp is simplified into mixtures of solid particles and water. The Finnie prediction model is applied to predict impeller erosion character. The simulation results of different solid particle size are compared with practical impeller erosion character, and the effects of solid particle size on impeller erosion character are obtained. Thus, numerical method to simulate impeller erosion characteristics of fibered pulp is investigated

  12. Erosion predictions of stock pump impellers based on liquid-solid two-phase fluid simulations

    Science.gov (United States)

    Xiao, Y. X.; Fang, B.; Zeng, C. J.; Yang, L. B.; Wang, F.; Wang, Z. W.

    2013-12-01

    Stock pumps cost 25 percent of total power consumption in a modern paper mill. Owing to the severe erosion of pump casing and impeller during operation, stock pump often results in efficiency drop and rising power consumption. A favourable prediction of the impeller wearing character can effective guide optimization design of stock pump impeller. Thereby it can reduce impeller wear and extend stock pump performance life. We simulated the three-dimensional unsteady solid-liquid two-phase flow characteristic in the hydraulic channel of a low specific speed stock pump with open and three blades impeller. The standard k- ε turbulent model and the pseudo-fluid model were adopted in simulation. Clearance between covers and impeller is taken into consideration in modelling, and pulp is simplified into mixtures of solid particles and water. The Finnie prediction model is applied to predict impeller erosion character. The simulation results of different solid particle size are compared with practical impeller erosion character, and the effects of solid particle size on impeller erosion character are obtained. Thus, numerical method to simulate impeller erosion characteristics of fibered pulp is investigated.

  13. Liquid Metal Pump Technologies for Nuclear Surface Power

    Science.gov (United States)

    Polzin, Kurt A.

    2007-01-01

    Multiple liquid metal pump options are reviewed for the purpose of determining the technologies that are best suited for inclusion in a nuclear reactor thermal simulator intended to rest prototypical space nuclear surface power system components. Conduction, induction and thermoelectric electromagnetic pumps are evaluated based on their performance characteristics and the technical issues associated with incorporation into a reactor system. A thermoelectric electromagnetic pump is selected as the best option for use in NASA-MSFC's Fission Surface Power-Primary Test Circuit reactor simulator based on its relative simplicity, low power supply mass penalty, flight heritage, and the promise of increased pump efficiency over those earlier pump designs through the use of skutterudite thermoelectric elements.

  14. Ferromagnetic Resonance Spin Pumping and Electrical Spin Injection in Silicon-Based Metal-Oxide-Semiconductor Heterostructures

    Science.gov (United States)

    Pu, Y.; Odenthal, P. M.; Adur, R.; Beardsley, J.; Swartz, A. G.; Pelekhov, D. V.; Flatté, M. E.; Kawakami, R. K.; Pelz, J.; Hammel, P. C.; Johnston-Halperin, E.

    2015-12-01

    We present the measurement of ferromagnetic resonance (FMR-)driven spin pumping and three-terminal electrical spin injection within the same silicon-based device. Both effects manifest in a dc spin accumulation voltage Vs that is suppressed as an applied field is rotated to the out-of-plane direction, i.e., the oblique Hanle geometry. Comparison of Vs between these two spin injection mechanisms reveals an anomalously strong suppression of FMR-driven spin pumping with increasing out-of-plane field Happz . We propose that the presence of the large ac component to the spin current generated by the spin pumping approach, expected to exceed the dc value by 2 orders of magnitude, is the origin of this discrepancy through its influence on the spin dynamics at the oxide-silicon interface. This convolution, wherein the dynamics of both the injector and the interface play a significant role in the spin accumulation, represents a new regime for spin injection that is not well described by existing models of either FMR-driven spin pumping or electrical spin injection.

  15. High repetition rate collisional soft x-ray lasers based on grazing incidence pumping

    Energy Technology Data Exchange (ETDEWEB)

    Luther, B M; Wang, Y; Larotonda, M A; Alessi, D; Berrill, M; Rocca, J J; Dunn, J; Keenan, R; Shlyaptsev, V N

    2005-11-18

    We discuss the demonstration of gain-saturated high repetition rate table-top soft x-ray lasers producing microwatt average powers at wavelengths ranging from 13.9 to 33 nm. The results were obtained heating a pre-created plasma with a picosecond optical laser pulse impinging at grazing incidence onto a pre-created plasma. This pumping geometry increases the energy deposition efficiency of the pump beam into the gain region, making it possible to saturate soft x-ray lasers in this wavelength range with a short pulse pump energy of only 1 J at 800 nm wavelength. Results corresponding to 5 Hz repetition rate operation of gain-saturated 14.7 nm Ni-like Pd and 32.6 nm line Ne-like Ti lasers pumped by a table-top Ti:sapphire laser are reported. We also discuss results obtained using a 1 {omega} 1054 nm pre-pulse and 2{omega} 527 nm short pulse from a Nd:glass pump laser. This work demonstrates the feasibility of producing compact high average power soft x-ray lasers for applications.

  16. Optimization of divergence angle of jet pump based on numerical simulation of interior flow field

    International Nuclear Information System (INIS)

    The divergence angle of a diffuser is one of the important structure parameters of the jet pumps, which has effect on the performance, interior flow field distribution and manufacture cost of the jet pump. In this paper, SIMPLE arithmetic and Realizable k-ε turbulence model is adopted to simulate the flow field and performance of jet pump of various divergence angles. The analysis on the centerline velocity, wall pressure distributions as well as the momentum correction coefficient and dynamic energy correction coefficient in the inlet and outlet of diffuser indicate that the divergence angle has less effect on the flow upstream the diffuser. It influences greatly the flow in the diffuser and downstream pipe. The effect of divergence angle on the performance and efficiency of jet pump is imposed by the resistance loss in the diffuser. Both the manufacture cost and pump efficiency should be considered together in the optimization of the divergence angle. Under a guideline of relatively changing 2.5% from the maximum efficiency point, the optimal divergence angle is proposed as 80-110 considering the overall dimension and manufacture cost. (authors)

  17. Electron-beam pumping of visible and ultraviolet gas lasers

    International Nuclear Information System (INIS)

    Several techniques for using direct electron-pumping of gas lasers are reviewed. The primary objective is to categorize pump geometries and to give guidelines for gun selection and pulser design. Examples and application of pump technology are given

  18. Tunable optical parametric generator based on the pump spatial walk-off

    CERN Document Server

    Cavanna, Andrea; Sharapova, Polina R; Taheri, Michael; Leuchs, Gerd; Chekhova, Maria V

    2015-01-01

    We suggest a novel optical parametric generator (OPG) in which one of the down-converted beams is spontaneously generated along the Poynting vector of the pump beam. In this configuration, the generation takes advantage of the walk-off of the extraordinary pump rather than being degraded by it. As a result the generated beams, signal and idler, are bright, due to a high conversion efficiency, spatially nearly single-mode, due to the preferred direction of the Poynting vector, tuneable over a wide range of wavelengths, and broadband. The two beams are also correlated in frequency and in the photon number per pulse. Furthermore due to their thermal statistics these beams can be used as a pump to efficiently generate other nonlinear processes.

  19. Numerical prediction of pressure fluctuations in a prototype pump turbine base on PANS methods

    Science.gov (United States)

    Liu, J. T.; Li, Y.; Gao, Y.; Hu, Q.; Wu, Y. L.

    2016-05-01

    Unsteady flow and pressure fluctuations within a prototypel pump turbine are numerically studied using a nonlinear Partial Averaged Navier Stokes (PANS) model. Pump turbine operating at different conditions with guide vanes opening angle 6° is simulated. Results revealed that the predictions of performance and relative peak-to-peak amplitude by PANS approach agree well with the experimental data. The amplitude of the pressure fluctuation in the vaneless space at turbine mode on a “S” curve increases with the decrease of the flow rate, and it has maximum value when it runs close to runaway line at turbine braking mode. The amplitude of the pressure fluctuation in the vaneless space at turbine braking mode on a “S” curve decreases with the reduce of the flow rate. The above high pressure fluctuations should be avoided during the design of pump turbines especially those operating at high-head condition.

  20. Development of Monitoring System of the RSG GAS Cooling Pump Based on Vibration Analysis

    International Nuclear Information System (INIS)

    The development of rotating machine system monitoring with vibration analysis, has been done. Research was done considering important of predictive maintenance cooling system pump using vibration analysis. Device of monitoring systems that used before require to be improved because it's only provided overall parameters and an old analogous meter systems. Research was done by arranging hardware, making software, testing and implementing this system at secondary pump of RSG GAS. In this research, hardware using NI-4551 digital signal analyze, accelerometer, and software using Labview Professional Edition 6.1 licensed. Examination and characterization indicate that the systems functioning well as vibration signal analyzer. Input frequency Response is 0.446 and dynamic range more than 90 db. Besides that, measurement application to secondary pump has also given FFT spectrum result that able to explain vibration phenomenon of a machine. For more accurate measurement applications, systems require to be developed because frequency resolution which still lower. (author)

  1. Design of Pumps for Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard

    1999-01-01

    This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid.......KEYWORDS: water, pump, design, vane, gear....

  2. ZnO film based surface acoustic wave micro-pump

    International Nuclear Information System (INIS)

    In this study, a micro-pump unit based on surface acoustic wave (SAW) on piezoelectric ZnO film is designed and fabricated as a micro-fluidic device. It employs a mechanical wave, which is generated electrically using an aluminum interdigital transducer (IDT), and propagates on the surface of the ZnO film. The ZnO film was used in this study because it has a high electromechanical coefficient and an excellent bonding with various substrate materials, in particular silicon. The sputtering parameters for ZnO film deposition have been optimized, and the ZnO films with different thickness from 1 micron to 5.5 microns were prepared. The film properties have been characterized using different methods, such as scanning electron microscopy, X-ray diffraction and atomic force microscopy. Aluminum IDT with a finger width and spacing of 8 microns was patterned on the ZnO film using a lift-off process. The frequency generated was measured using a network analyzer, and it varies from 130 MHz to 180 MHz as a function of film thickness. A signal generator was used to generate the frequency with a power amplifier to amplify the signal, which was then applied to aluminum IDT to generate the surface acoustic wave. If a liquid droplet exists on the surface carrying the acoustic wave, the energy and the momentum of the SAW will be coupled into the fluid, causing the liquid to vibrate and move on film surface. The strength of this movement is determined by the applied voltage and frequency. The volume of the liquid drop loaded on the SAW device in this study is of several hundreds of nanoliters. The movement of the liquid inside the droplet and also on the ZnO film surface can be demonstrated. The performance of ZnO SAW device was characterized as a function of film thickness

  3. Potential Coastal Pumped Hydroelectric Energy Storage Locations Identified using GIS-based Topographic Analysis

    Science.gov (United States)

    Parsons, R.; Barnhart, C. J.; Benson, S. M.

    2013-12-01

    Large-scale electrical energy storage could accommodate variable, weather dependent energy resources such as wind and solar. Pumped hydroelectric energy storage (PHS) and compressed energy storage area (CAES) have life cycle energy and financial costs that are an order of magnitude lower than conventional electrochemical storage technologies. However PHS and CAES storage technologies require specific geologic conditions. Conventional PHS requires an upper and lower reservoir separated by at least 100 m of head, but no more than 10 km in horizontal distance. Conventional PHS also impacts fresh water supplies, riparian ecosystems, and hydrologic environments. A PHS facility that uses the ocean as the lower reservoir benefits from a smaller footprint, minimal freshwater impact, and the potential to be located near off shore wind resources and population centers. Although technologically nascent, today one coastal PHS facility exists. The storage potential for coastal PHS is unknown. Can coastal PHS play a significant role in augmenting future power grids with a high faction of renewable energy supply? In this study we employ GIS-based topographic analysis to quantify the coastal PHS potential of several geographic locations, including California, Chile and Peru. We developed automated techniques that seek local topographic minima in 90 m spatial resolution shuttle radar topography mission (SRTM) digital elevation models (DEM) that satisfy the following criteria conducive to PHS: within 10 km from the sea; minimum elevation 150 m; maximum elevation 1000 m. Preliminary results suggest the global potential for coastal PHS could be very significant. For example, in northern Chile we have identified over 60 locations that satisfy the above criteria. Two of these locations could store over 10 million cubic meters of water or several GWh of energy. We plan to report a global database of candidate coastal PHS locations and to estimate their energy storage capacity.

  4. Optimizing wind pumps system for crop irrigation based on wind data processing

    Science.gov (United States)

    Ruiz, Fernando; Tarquis, Ana M.; Sanchez, Raúl; Garcia, Jose Luis

    2015-04-01

    Crop irrigation is a major consumer of energy that can be resolved with renewable ones, such as wind, which has experienced recent developments in the area of power generation. Therefore, wind power can play an interesting role in irrigation projects in different areas [1]. A simple methodology has been developed in previous papers for technical evaluation of windmills for irrigation water pumping [2]. This methodology can determine the feasibility of the technology and the levels of daily irrigation demand satisfied by windmills. The present work compared the possibilities of this methodology adjusting the three-hourly wind velocity to the Weibull II distribution function, without considering the time sequence [2], or processing wind data using time series analysis. The study was applied to practical cases of wind pumps for irrigation of crops, both in the outside (corn) and inside greenhouses (tomato). The analysis showed that the use of three hourly time series analysis supplied a more realistic modelling of the situation with a better optimization of the water storage tank of the wind pump facility taking into account the risk of calm periods in which the pumping is null. A factor to consider in this study is available precision of the wind sampling rate. References [1] Díaz-Méndez, R., Adnan Rasheed, M. Peillón, A. Perdigones, R. Sánchez, A.M. Tarquis, José L. García-Fernández. Wind pumps for irrigating greenhouse crops: comparison in different socio-economical frameworks. Biosystems Engineering, 128, 21-28, 2014. [2] Peillón, M., Sánchez, R., Tarquis, A.M., García, J.L. The use of wind pumps for greenhouse microirrigation: A case study for tomato in Cuba. Agricultural Water Management, 120, 107-114, 2013.

  5. Evaporation based micro pump integrated into a scanning force microscope probe

    OpenAIRE

    Heuck, F.; Hug, T.; Akiyama, Terunobu; Frederix, P. L. T. M.; Engel, A.; Meister, André; Heinzelmann, Harry; de Rooij, Nicolaas F.; Staufer, Urs

    2010-01-01

    A micro pump was integrated into a scanning force microscope probe for circulating liquid through its hollow cantilever and tip. The interior cross section of the cantilever was 2.25 μm × 3.75 μm. All fluidic parts were made of SiO2, while the tip apex was made of Si3N4. The key fabrication techniques were silicon wafer bonding and wet-oxidation. The pumping mechanism was relying on the enhanced evaporation at an enlarged water/air interface at the exit of the microchannel. Capillary forces c...

  6. Optimization of compound gear pump

    Institute of Scientific and Technical Information of China (English)

    栾振辉

    2002-01-01

    This paper introduces the performances of compound gear pump. Based on the target of having the smallest mass per unit volume, the paper established a mathematical model of optimization, and obtained the results of optimization of the pump.

  7. Orbital Liquid Oxygen Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed work will develop a pump, which is based on two novel and unique design features. The first feature is a lobed pumping mechanism which operates with...

  8. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  9. Experimental validation of autonomous PV-based water pumping system optimum sizing

    International Nuclear Information System (INIS)

    The progress met in the world market of photovoltaics underlines the maturity of investments realized, guarantees the reliability of the technology utilized and designates the variety of applications in covering the energy demands of both stand-alone and grid connected consumers. Concerning stand-alone systems, the incorporation of photovoltaic systems in water pumping applications is thought to be one of the most popular and ideal uses of solar energy exploitation, especially under the common allegation of coincidence between insolation and water demand. In this study, an attempt to investigate the opportunities of a PV powered water pumping system able to meet additional - apart from the water pump - electricity loads, results in the development of an optimum sizing methodology which is accordingly validated by experimental measurements. From the results obtained, it becomes clear that a properly designed PV-pumping configuration of 610 Wp is capable of covering both the electricity (max 2 kWh/day) and the water (max 400 L/h) management demands of a large variety of remote consumers. (author)

  10. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis

    Science.gov (United States)

    Wang, Guorong; Zhong, Lin; He, Xia; Lei, Zhongqing; Hu, Gang; Li, Rong; Wang, Yunhai

    2015-01-01

    The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality. An optimal spring stiffness parameter of 14.6 N/mm was obtained, and the volumetric efficiency of the pumping valve increased by 4‰ in comparison to results obtained with the original spring stiffness of 10.09N/mm. The experimental results indicated that the mathematical model and FSI method could provide an effective approach for the subsequent improvement of valve reliability, volumetric efficiency and lifespan. PMID:26488290

  11. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis.

    Directory of Open Access Journals (Sweden)

    Guorong Wang

    Full Text Available The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality. An optimal spring stiffness parameter of 14.6 N/mm was obtained, and the volumetric efficiency of the pumping valve increased by 4‰ in comparison to results obtained with the original spring stiffness of 10.09N/mm. The experimental results indicated that the mathematical model and FSI method could provide an effective approach for the subsequent improvement of valve reliability, volumetric efficiency and lifespan.

  12. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis.

    Science.gov (United States)

    Wang, Guorong; Zhong, Lin; He, Xia; Lei, Zhongqing; Hu, Gang; Li, Rong; Wang, Yunhai

    2015-01-01

    The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality. An optimal spring stiffness parameter of 14.6 N/mm was obtained, and the volumetric efficiency of the pumping valve increased by 4‰ in comparison to results obtained with the original spring stiffness of 10.09N/mm. The experimental results indicated that the mathematical model and FSI method could provide an effective approach for the subsequent improvement of valve reliability, volumetric efficiency and lifespan. PMID:26488290

  13. Research on Three-Dimensional Unsteady Turbulent Flow in Multistage Centrifugal Pump and Performance Prediction Based on CFD

    Directory of Open Access Journals (Sweden)

    Zhi-jian Wang

    2013-01-01

    Full Text Available The three-dimensional flow physical model of any stage of the 20BZ4 multistage centrifugal pump is built which includes inlet region, impeller flow region, guide-vane flow region and exit region. The three-dimensional unsteady turbulent flow numerical model is created based on Navier-Stoke solver and standard k-ε turbulent equations. The method of multireference frame (MRF and SIMPLE algorithm are used to simulate the flow in multistage centrifugal pump based on FLUENT software. The distributions of relative velocity, absolute velocity, static pressure, and total pressure in guide vanes and impellers under design condition are analyzed. The simulation results show that the flow in impeller is mostly uniform, without eddy, backflow, and separation flow, and jet-wake phenomenon appears only along individual blades. There is secondary flow at blade end and exit of guide vane. Due to the different blade numbers of guide vane and impeller, the total pressure distribution is asymmetric. This paper also simulates the flow under different working conditions to predict the hydraulic performances of centrifugal pump and external characteristics including flow-lift, flow-shaft power, and flow-efficiency are attained. The simulation results are compared with the experimental results, and because of the mechanical losses and volume loss ignored, there is a little difference between them.

  14. Numerical Simulation of Self-Pumped Phase Conjugate Plane-Curve Loop Mirror Based on Photorefractive Nonlinearity

    Institute of Scientific and Technical Information of China (English)

    Mehran Vahdani Moghaddam; Zeynab Chenari; Hamid Latifi; Vladimir Vladimirovich Shuvalov; Konestantin Valentinovich Rudenko

    2008-01-01

    @@ We deal with computer simulation of a transient process in a self-pumped phase conjugate plane-curve loop mirror based on BaTiO3. In optimal circumstances the nonlinear reflectivity and fidelity of such a mirror respectively achieve 0.80-0.90 and 0.95-0.98. The generation of conjugate wave-front occurs due to scattering from the dynamic hologram which is produced in the region of self-intersection of forward and backward beams. In such a model the scenario of passing to unstable generation regimes is similar to the self-pumped phase conjugate plane-plane loop mirror and substantially differs from a single-crystal double phase conjugate mirror.

  15. A power management system for energy harvesting and wireless sensor networks application based on a novel charge pump circuit

    Science.gov (United States)

    Aloulou, R.; De Peslouan, P.-O. Lucas; Mnif, H.; Alicalapa, F.; Luk, J. D. Lan Sun; Loulou, M.

    2016-05-01

    Energy Harvesting circuits are developed as an alternative solution to supply energy to autonomous sensor nodes in Wireless Sensor Networks. In this context, this paper presents a micro-power management system for multi energy sources based on a novel design of charge pump circuit to allow the total autonomy of self-powered sensors. This work proposes a low-voltage and high performance charge pump (CP) suitable for implementation in standard complementary metal oxide semiconductor (CMOS) technologies. The CP design was implemented using Cadence Virtuoso with AMS 0.35μm CMOS technology parameters. Its active area is 0.112 mm2. Consistent results were obtained between the measured findings of the chip testing and the simulation results. The circuit can operate with an 800 mV supply and generate a boosted output voltage of 2.835 V with 1 MHz as frequency.

  16. Research on an Intelligent Decision Support System for a Conceptual Innovation Design of Pumping Units Based on TRIZ

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Attention is concentrated on how to perform the innovative design during the process of pumping unit conceptual design, and how to enhance design efficiency and inspire creativity. Aiming at the shortages of conceptual design, introducing the theory of inventive problem solving (TRIZ) into the mechanical product design for producing innovative ideas, and using the advanced computer-aided technique, the intelligent decision support system (IDSS) based on TRIZ (TRIZ-IDSS) has been constructed. The construction method, system structure, conceptual production, decision-making and evaluation of the problem solving subsystem are discussed. The innovative conceptual design of pumping units indicates that the system can help the engineers open up a new space of thinking, overcome the thinking inertia, and put forward innovative design concepts. This system also can offer the scientific instructions for the innovative design of mechanical products.

  17. Yb fiber laser pumped mid-IR source based on difference frequency generation and its application to ammonia detection

    Science.gov (United States)

    Matsuoka, N.; Yamaguchi, S.; Nanri, K.; Fujioka, T.; Richter, D.; Tittel, F. K.

    2001-01-01

    A Yb fiber laser pumped cw narrow-linewidth tunable mid-IR source based on a difference frequency generation (DFG) in a periodically poled LiNbO3 (PPLN) crystal for trace gas detection was demonstrated. A high power Yb fiber laser and a distributed feedback (DFB) laser diode were used as DFG pump sources. This source generated mid-IR at 3 microns with a powers of 2.5 microW and a spectral linewidth of less than 30 MHz. A frequency tuning range of 300 GHz (10 cm-1) was obtained by varying the current and temperature of the DFB laser diode. A high-resolution NH3 absorption Doppler-broadened spectrum at 3295.4 cm-1 (3.0345 microns) was obtained at a cell pressure of 27 Pa from which a detection sensitivity of 24 ppm m was estimated.

  18. Microfluidic pumping, routing and metering by contactless metal-based electro-osmosis.

    Science.gov (United States)

    Fu, Xiaotong; Mavrogiannis, Nicholas; Doria, Steven; Gagnon, Zachary

    2015-09-01

    Over the past decade, many microfluidic platforms for fluid processing have been developed in order to perform on-chip fluidic manipulations. Many of these methods, however, require expensive and bulky external supporting equipment, which are not typically applicable for microsystems requiring portability. We have developed a new type of portable contactless metal electro-osmotic micropump capable of on-chip fluid pumping, routing and metering. The pump operates using two pairs of gallium metal electrodes, which are activated using an external voltage source, and separated from a main flow channel by a thin micron-scale PDMS membrane. The thin contactless membrane allows for field penetration and electro-osmotic (EO) flow within the microchannel, but eliminates electrode damage and sample contamination commonly associated with traditional DC electro-osmotic pumps that utilize electrodes in direct contact with the working fluid. The maximum flow rates and pressures generated by the pump using DI water as a working buffer are 10 nL min(-1) and 30 Pa, respectively. With our current design, the maximum operational conductivity where fluid flow is observed is 0.1 mS cm(-1). Due to the small size and simple fabrication procedure, multiple micropump units can be integrated into a single microfluidic device for automated on-chip routing and sample metering applications. We experimentally demonstrated the ability to quantify micropump electro-osmotic flowrate and pressure as a function of applied voltage, and developed a mathematical model capable of predicting the performance of a contactless micropump for a given external load and internal hydrodynamic microchannel resistance. Finally, we showed that by activating specific pumps within a microchannel network, our micropumps are capable of routing microchannel fluid flow and generating plugs of solute. PMID:26053965

  19. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  20. Efficiency of pumping gasoline in service station

    International Nuclear Information System (INIS)

    This paper studies a gasoline pumping system and evaluates the efficiency of pumping gasoline in service station. The primary motivation of the study is to determine how to improve the efficiency of pumping gasoline in service station. An experimental test rig is setup. After evaluating the efficiency of the pump under different conditions, it was found that the performance is quite different when pumping different medium, which is not match with the pump manufacturer's catalog. And it provides us a guidance to choose the operational parameters of pumps. A phenomenon has been observed which result of the appearance of the BEP (best efficiency point) and the proof needs more works.

  1. Effects of Pumping Sizes on THz Radiation Based on Ultrashort Light Pulse Optical Rectification for High Spatial Resolution T-Ray Imaging

    International Nuclear Information System (INIS)

    We present our experimental studies on the effects of the pumping sizes on THz radiation based on ultrashort light pulse optical rectification for high spatial resolution T-Ray imaging. Our experiments show that high spatial resolution T-ray imaging requires both thin THz emitter and sample, and rigorous tolerance of the gap between the sample and the emitter, as well as small pumping size which usually much smaller compared with THz wavelength. Such a small pumping size results in dramatic decrease of the THz wave power, which originates from strong diffraction of THz wave, the depolarization of the focused tightly pumping beam, the spatial filtering of the emitter exit-surface, and the strong phase-mismatching between the pumping and the high spatial Fourier components of the THz signal, rather than two-photon absorption

  2. Effects of Pumping Sizes on THz Radiation Based on Ultrashort Light Pulse Optical Rectification for High Spatial Resolution T-Ray Imaging

    Institute of Scientific and Technical Information of China (English)

    XU Shi-Xiang; DAI Xiao-Ming; YANG Xiao-Hua; LI Jing-Zhen

    2008-01-01

    @@ We present our experimental studies on the effects of the pumping sizes on THz radiation based on ultrashort light pulse optical rectification for high spatial resolution T-Ray imaging.Our experiments show that high spatial resolution T-ray imaging requires both thin THz emitter and sample, and rigorous tolerance of the gap between the sample and the emitter, as well as small pumping size which usually much smaller compared with THz wavelength.Such a small pumping size results in dramatic decrease of the THz wave power, which originates from strong diffraction of THz wave, the depolarization of the focused tightly pumping beam, the spatial filtering of the emitter exit-surface, and the strong phase-mismatching between the pumping and the high spatial Fourier components of the THz signal, rather than two-photon absorption.

  3. Magnetic buoyancy instabilities in the presence of magnetic flux pumping at the base of the solar convection zone

    Science.gov (United States)

    Barker, Adrian J.; Silvers, Lara J.; Proctor, Michael R. E.; Weiss, Nigel O.

    2012-07-01

    We perform idealized numerical simulations of magnetic buoyancy instabilities in three dimensions, solving the equations of compressible magnetohydrodynamics in a model of the solar tachocline. In particular, we study the effects of including a highly simplified model of magnetic flux pumping in an upper layer ('the convection zone') on magnetic buoyancy instabilities in a lower layer ('the upper parts of the radiative interior - including the tachocline'), to study these competing flux transport mechanisms at the base of the convection zone. The results of the inclusion of this effect in numerical simulations of the buoyancy instability of both a preconceived magnetic slab and a shear-generated magnetic layer are presented. In the former, we find that if we are in the regime that the downward pumping velocity is comparable with the Alfvén speed of the magnetic layer, magnetic flux pumping is able to hold back the bulk of the magnetic field, with only small pockets of strong field able to rise into the upper layer. In simulations in which the magnetic layer is generated by shear, we find that the shear velocity is not necessarily required to exceed that of the pumping (therefore the kinetic energy of the shear is not required to exceed that of the overlying convection) for strong localized pockets of magnetic field to be produced which can rise into the upper layer. This is because magnetic flux pumping acts to store the field below the interface, allowing it to be amplified both by the shear and by vortical fluid motions, until pockets of field can achieve sufficient strength to rise into the upper layer. In addition, we find that the interface between the two layers is a natural location for the production of strong vertical gradients in the magnetic field. If these gradients are sufficiently strong to allow the development of magnetic buoyancy instabilities, strong shear is not necessarily required to drive them (cf. previous work by Vasil & Brummell). We find

  4. Qualification Testing of Laser Diode Pump Arrays for a Space-Based 2-micron Coherent Doppler Lidar

    Science.gov (United States)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, Nathaniel R.; Barnes, Bruce W.; Singh, Upendra N.; Kavaya, Michael J.

    2007-01-01

    The 2-micron thulium and holmium-based lasers being considered as the transmitter source for space-based coherent Doppler lidar require high power laser diode pump arrays operating in a long pulse regime of about 1 msec. Operating laser diode arrays over such long pulses drastically impact their useful lifetime due to the excessive localized heating and substantial pulse-to-pulse thermal cycling of their active regions. This paper describes the long pulse performance of laser diode arrays and their critical thermal characteristics. A viable approach is then offered that allows for determining the optimum operational parameters leading to the maximum attainable lifetime.

  5. Kilohertz high power extracavity KGW yellow raman lasers based on pulse LD side-pumped ceramic Nd: YAG

    Science.gov (United States)

    Bai, Y.; Chen, X. M.; Guo, J. X.; Zhang, H. L.; Bai, J. T.; Ren, Z. Y.

    2012-03-01

    We report an efficient operation of a kilohertz nanosecond extracavity KGd(WO4)2 (KGW) crystal Raman yellow laser, which is pumped by a 532 nm lasers based on pulse laser diode (LD) side-pumped ceramic Nd: YAG, BBO electro-optical Q-switched and LBO crystal extracavity frequency doubling. With the 5 W, 10 ns and 1 kHz output power pumped at 532 nm, we obtained 2.58 W, 7.4 ns, 1 kHz second Stokes Raman laser output at 579.54 nm for 768 cm-1 Raman shift of KGW crystal, corresponding to a conversion efficiency of 51.4%. By changing the KGW crystal orientation, we further obtained 3.18 W, 7.8 ns, 1 kHz Raman pulses at 588.33 nm for 901 cm-1 Raman shift, corresponding to a conversion efficiency of 63.3%. The beam quality factors M2 of 579.54 and 588.33 nm were ( M {/x-579.54 2} = 5.829, M {/y-579.54 2} = 6.336) and ( M {/x-588.33 2} = 6.405, M {/y-588.33 2} = 6.895), respectively.

  6. A compact diode-pumped pulsed Nd:YAG slab laser based on a master oscillator power amplifier configuration

    Science.gov (United States)

    Maleki, A.; Kavosh Tehrani, M.; Saghafifar, H.; Moghtader Dindarlu, M. H.; Ebadian, H.

    2016-02-01

    In this paper, the design and construction of a pulsed Nd:YAG laser is described. The structure of this laser is based on a master oscillator power amplifier system. A master oscillator is an electro-optical Q-switched Nd:YAG rod laser. Face-pumping is used for the excitation of the slab structure, and a double-pass method is designed for the amplification stages. Two Nd:YAG zigzag slabs are utilized as power amplification stages in this laser. The laser diodes are stacked in a compact configuration and are used for rod and slabs pumping. The total pump energy in the amplifier stages is 3200 mJ at 808 nm. The output pulse energy achieved at 1064 nm is about 850 mJ of 10 ns pulse duration corresponding to 26.5% optical-to-optical conversion efficiency. Moreover, this laser can generate pulse energies around 430 mJ at 532 nm. The dependence of the output energy of MOPA and second harmonic generation operations on different pulse repetition rates (PRRs) from 1 to 100 Hz has been investigated. Experimental results show that the maximum fluctuations of the output energies are about 2.5 and 4% for 1064 and 532 nm, respectively.

  7. Laser pumping Cs atom magnetometer of theory research based on gradient tensor measuring

    International Nuclear Information System (INIS)

    At present, due to space exploration, military technology, geological exploration, magnetic navigation, medical diagnosis and biological magnetic fields study of the needs of research and development, the magnetometer is given strong driving force. In this paper, it will discuss the theoretical analysis and system design of laser pumping cesium magnetometer, cesium atomic energy level formed hyperfine structure with the I-J coupling, the hyperfine structure has been further split into Zeeman sublevels for the effects of magnetic field. To use laser pump and RF magnetic field make electrons transition in the hyperfine structure to produce the results of magneto-optical double resonance, and ultimately through the resonant frequency will be able to achieve accurate value of the external magnetic field. On this basis, we further have a discussion about magnetic gradient tensor measuring method. To a large extent, it increases the magnetic field measurement of information.

  8. Use of a yeast-based membrane protein expression technology to overexpress drug resistance efflux pumps.

    Science.gov (United States)

    Lamping, Erwin; Cannon, Richard D

    2010-01-01

    Azole antifungal drugs are used widely to treat people with oral fungal infections. Unfortunately, fungi can develop resistance to these drugs. This resistance can be due to the overexpression or mutation of cytochrome P450 14alpha-lanosterol demethylase, also known as ERG11 or CYP51, and/or the overexpression of membrane-located multidrug efflux pumps. We have developed a heterologous membrane protein expression system that can be used to study the structure and function of these proteins in the non-pathogenic, genetically stable, and versatile eukaryotic model organism, Saccharomyces cerevisiae. In this chapter we describe the techniques used to express the Candida albicans efflux pump Cdr1p in S. cerevisiae. PMID:20717788

  9. Process-based approach of heat pump projects; Procesmatig werken bij warmtepompprojecten

    Energy Technology Data Exchange (ETDEWEB)

    Ten Bolscher, G.H. [DWA Installatie- en Energieadvies, Bodegraven (Netherlands)

    2012-04-15

    A process-oriented approach in heat pump projects can prevent various kinds of problems, for example complaints of users on too high energy costs, mediocre temperature control or being bound by a contract for exploitation and maintenance. [Dutch] Met een procesmatige aanpak in warmtepompprojecten kunnen diverse problemen worden voorkomen. Bijvoorbeeld klachten van gebruikers over te hoge energiekosten, matige temperatuurregeling of de gebondenheid aan een exploitatie- en onderhoudscontract.

  10. Multi-tap photonic microwave filter based on two-pump fiber optical parametric amplifier

    OpenAIRE

    Li, J.; Cheung, KKY; Xu, X; Wong, KKY

    2009-01-01

    We propose and demonstrate a novel approach to implement a multi-tap photonic microwave filter. By using a two-pump fiber optical parametric amplifier (OPA), the number of signal laser sources needed is only half of the number of filter taps because new frequency components idlers are generated. Moreover, the free spectral range (FSR) of the proposed filter can be changed by simply changing the wavelength spacing between the signals. In our experiment, an 8-tap photonic microwave filter has b...

  11. Artificial neural network based modeling of performance characteristics of deep well pumps with splitter blade

    International Nuclear Information System (INIS)

    Experimental studies were made to investigate the effects of splitter blade length (25%, 35%, 50%, 60% and 80% of the main blade length) on the pump characteristics of deep well pumps for different blade numbers (z=3, 4, 5, 6 and 7). In this study, an artificial neural network (ANN) was used for modeling the performance of deep well pumps with splitter blades. Two hundred and ten experimental results were used to train and test. Forty-two patterns have been randomly selected and used as the test data. The main parameters for the experiments are the blade number (z), non-dimensional splitter blade length (L-bar ), flow rate (Q, l/s), head (Hm, m), efficiency (η, %) and power (Pe, kW). z, L-bar and Q have been used as the input layer, and Hm and η have also been used as the output layer. The best training algorithm and number of neurons were obtained. Training of the network was performed using the Levenberg-Marquardt (LM) algorithm. To determine the effect of the transfer function, different ANN models are trained, and the results of these ANN models are compared. Some statistical methods; fraction of variance (R2) and root mean squared error (RMSE) values, have been used for comparison

  12. Inquiry-Based Learning in Teacher Education: A Primary Humanities Example

    Science.gov (United States)

    Preston, Lou; Harvie, Kate; Wallace, Heather

    2015-01-01

    Inquiry-based learning features strongly in the new Australian Humanities and Social Sciences curriculum and increasingly in primary school practice. Yet, there is little research into, and few exemplars of, inquiry approaches in the primary humanities context. In this article, we outline and explain the implementation of a place-based simulation…

  13. High brightness fiber laser pump sources based on single emitters and multiple single emitters

    Science.gov (United States)

    Scheller, Torsten; Wagner, Lars; Wolf, Jürgen; Bonati, Guido; Dörfel, Falk; Gabler, Thomas

    2008-02-01

    Driven by the potential of the fiber laser market, the development of high brightness pump sources has been pushed during the last years. The main approaches to reach the targets of this market had been the direct coupling of single emitters (SE) on the one hand and the beam shaping of bars and stacks on the other hand, which often causes higher cost per watt. Meanwhile the power of single emitters with 100μm emitter size for direct coupling increased dramatically, which also pushed a new generation of wide stripe emitters or multi emitters (ME) of up to 1000μm emitter size respectively "minibars" with apertures of 3 to 5mm. The advantage of this emitter type compared to traditional bars is it's scalability to power levels of 40W to 60W combined with a small aperture which gives advantages when coupling into a fiber. We show concepts using this multiple single emitters for fiber coupled systems of 25W up to 40W out of a 100μm fiber NA 0.22 with a reasonable optical efficiency. Taking into account a further efficiency optimization and an increase in power of these devices in the near future, the EUR/W ratio pushed by the fiber laser manufacturer will further decrease. Results will be shown as well for higher power pump sources. Additional state of the art tapered fiber bundles for photonic crystal fibers are used to combine 7 (19) pump sources to output powers of 100W (370W) out of a 130μm (250μm) fiber NA 0.6 with nominal 20W per port. Improving those TFB's in the near future and utilizing 40W per pump leg, an output power of even 750W out of 250μm fiber NA 0.6 will be possible. Combined Counter- and Co-Propagated pumping of the fiber will then lead to the first 1kW fiber laser oscillator.

  14. A novel static frequency converter based on multilevel cascaded H-bridge used for the startup of synchronous motor in pumped-storage power station

    International Nuclear Information System (INIS)

    Research highlights: → A novel Static Frequency Converter (SFC) based on multilevel cascaded H-bridge (CHB) topology is proposed and used for the reversible pump-generating units in pumped-storage power station. → The novel SFC based on CHB has compact configuration, low current harmonic distortion and fast speed response. → Rotor position and Grid connection are realized successfully by the novel SFC. -- Abstract: A novel static frequency converter (SFC) is proposed and is used firstly to start the reversible pump-generating units in pumped-storage power station. Multilevel cascaded H-bridge (CHB) topology and Insulated Gate Bipolar Transistor (IGBT) are applied in the novel SFC. In comparison with the conventional SFC adopting load-commutated inverter (LCI) which is composed of silicon-controlled rectifier (SCR), the novel one has plenty of advantages such as compact configuration, low current harmonic distortion and fast speed response, and these advantages have been verified during 2-year operation at Xiang Hong Dian Pumped-storage power station in China. This application shows that the novel SFC greatly enhances the reliability and success rate of connecting to grid for starting up the pump-generating units. The principle, characteristic and performance of the novel SFC are described in this paper, and some key issues related to the startup of the units of the pumped-storage power station are also presented.

  15. Normetex Pump Alternatives Study

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Elliot A.

    2013-04-25

    A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

  16. Pumping life

    DEFF Research Database (Denmark)

    Sitsel, Oleg; Dach, Ingrid; Hoffmann, Robert Daniel

    2012-01-01

    The name PUMPKIN may suggest a research centre focused on American Halloween traditions or the investigation of the growth of vegetables – however this would be misleading. Researchers at PUMPKIN, short for Centre for Membrane Pumps in Cells and Disease, are in fact interested in a large family of...... membrane proteins: P-type ATPase pumps. This article takes the reader on a tour from Aarhus to Copenhagen, from bacteria to plants and humans, and from ions over protein structures to diseases caused by malfunctioning pump proteins. The magazine Nature once titled work published from PUMPKIN ‘Pumping ions......’. Here we illustrate that the pumping of ions means nothing less than the pumping of life....

  17. Centrifugal pumps

    CERN Document Server

    Gülich, Johann Friedrich

    2014-01-01

    This book gives an unparalleled, up-to-date, in-depth treatment of all kinds of flow phenomena encountered in centrifugal pumps including the complex interactions of fluid flow with vibrations and wear of materials. The scope includes all aspects of hydraulic design, 3D-flow phenomena and partload operation, cavitation, numerical flow calculations, hydraulic forces, pressure pulsations, noise, pump vibrations (notably bearing housing vibration diagnostics and remedies), pipe vibrations, pump characteristics and pump operation, design of intake structures, the effects of highly viscous flows, pumping of gas-liquid mixtures, hydraulic transport of solids, fatigue damage to impellers or diffusers, material selection under the aspects of fatigue, corrosion, erosion-corrosion or hydro-abrasive wear, pump selection, and hydraulic quality criteria. As a novelty, the 3rd ed. brings a fully analytical design method for radial impellers, which eliminates the arbitrary choices inherent to former design procedures. The d...

  18. Space rocket engine on the base of the reactor-pumped laser for the interplanetary flights and earth orbital applications

    International Nuclear Information System (INIS)

    In this report the concept of vehicle-based reactor-laser engine for long time interplanetary and interorbital (LEO to GEO) flights is proposed. Reactor-pumped lasers offer the perspective way to create on the base of modern nuclear and lasers technologies the low mass and high energy density, repetitively pulsed vehicle-based laser of average power 100 kW. Nowadays the efficiency of nuclear-to-optical energy conversion reached the value of 2-3%. The demo model of reactor-pumped laser facility is under construction in Institute for Physics and Power Engineering (Obninsk, Russia). It enable us to hope that using high power laser on board of the vehicle could make the effective space laser engine possible. Such engine may provide the high specific impulse ∼1000-2000 s with the thrust up to 10-100 n. Some calculation results of the characteristics of vehicle-based reactor-laser thermal engine concept are also presented

  19. LD Side-Pumped Passive Mode-Locked TEM00 Nd:YAG Laser Based on SESAM

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ling; GUO Lin; XIONG Bo; YU Hai-Juan; SUN Lu; HOU Wei; LIN Xue-Chun; LI Jin-Min

    2010-01-01

    @@ We report an LD side-pumped continuous-wave passive mode-locked Nd:YA G laser with a Z-type folded cavity based on a semiconductor saturable absorber mirror (SESAM).The average output power 2.95 W of mode-locked laser with electro-optical conversion efficiency of 1.3% and high beam quality (M2x=1.25 and M2y=1.22) is achieved.The repetition rate of mode-locked pulse of 88 MHz with pulse energy of 34 nJ is obtained.

  20. Use of expert judgment in the development and evaluation of risk-based inservice testing strategies for pumps and valves

    Energy Technology Data Exchange (ETDEWEB)

    McAllister, W.J.; Perdue, R.K.; Balkey, K.R.; Closky, N.B. [and others

    1996-12-01

    This paper describes a rigorous approach for quantitatively evaluating inservice testing effectiveness that evolved from two pilot plant studies. These studies prototyped methodologies for designing and selecting inservice testing (IST) strategies in a manner structured to insure that the targeted components will perform their required safety functions while minimizing life cycle inservice testing costs. The paper concentrates on the use of expert judgment in developing test effectiveness measures that move risk-based methods beyond ranking to optimization of plant IST programs. Selected results for check valves and pumps are shown to illustrate the practical significance of the approach.

  1. Means-End based Functional Modeling for Intelligent Control: Modeling and Experiments with an Industrial Heat Pump System

    DEFF Research Database (Denmark)

    Saleem, Arshad

    2007-01-01

    The purpose of this paper is to present a Multilevel Flow Model (MFM) of an industrial heat pump system and its use for diagnostic reasoning. MFM is functional modeling language supporting an explicit means-ends intelligent control strategy for large industrial process plants. The model is used in...... several diagnostic experiments analyzing different fault scenarios. The model and results of the experiments are explained and it is shown how MFM based intelligent modeling and automated reasoning can improve the fault diagnosis process significantly....

  2. Use of expert judgment in the development and evaluation of risk-based inservice testing strategies for pumps and valves

    International Nuclear Information System (INIS)

    This paper describes a rigorous approach for quantitatively evaluating inservice testing effectiveness that evolved from two pilot plant studies. These studies prototyped methodologies for designing and selecting inservice testing (IST) strategies in a manner structured to insure that the targeted components will perform their required safety functions while minimizing life cycle inservice testing costs. The paper concentrates on the use of expert judgment in developing test effectiveness measures that move risk-based methods beyond ranking to optimization of plant IST programs. Selected results for check valves and pumps are shown to illustrate the practical significance of the approach

  3. CLASSICAL AREAS OF PHENOMENOLOGY: Investigation of pump-wavelength dependence of terahertz-wave parametric oscillator based on LiNbO3

    Science.gov (United States)

    Sun, Bo; Liu, Jin-Song; Li, En-Bang; Yao, Jian-Quan

    2009-07-01

    This paper investigates the performances of terahertz-wave parametric oscillators (TPOs) based on the LiNbO3 crystal at different pump wavelengths. The calculated results show that TPO characteristics, including the frequency tuning range, the THz-wave gain and the stability of THz-wave output direction based on the Si-prism coupler, can be significantly improved by using a short-wavelength pump. It also demonstrates that a long-wavelength-pump allows the employment of a short TPO cavity due to an enlarged phase-matching angle, that is, an increased angular separation between the pump and oscillated Stokes beams under the THz-wave generation at a specific frequency. The study provides an useful guide and a theoretical basis for the further improvement of TPO systems.

  4. Stochastic pumping of ions based on colored noise in bacterial channels under acidic stress.

    Science.gov (United States)

    López, M Lidón; Queralt-Martín, María; Alcaraz, Antonio

    2016-07-21

    Fluctuation-driven ion transport can be obtained in bacterial channels with the aid of different types of colored noise including the biologically relevant Lorentzian one. Using the electrochemical rectification of the channel current as a ratchet mechanism we observe transport of ions up to their concentration gradient under conditions similar to that met in vivo, namely moderate pH gradients and asymmetrically charged lipid membranes. We find that depending on the direction of the concentration gradient the channel can pump either cations or anions from the diluted side to the concentrated one. We discuss the possible relevance of this phenomenon for the pH homeostasis of bacterial cells. PMID:27349445

  5. Observer based Model Identification of Heat Pumps in a Smart Grid

    OpenAIRE

    Andersen, Palle; Pedersen, Tom S.; Nielsen, Kirsten M.

    2012-01-01

    The extensive growth of installed wind energy plants in Denmark leads to increasing balancing problems in the power grid due to the nature of wind fields and variations in consumption. One way to overcome these problems is to move consumption to times where wind power otherwise cause overproduction. A part of a solution can be to take advantage of floor heat capacity in single-family houses using heat pumps.This large heat capacity makes it possible to move consumption without compromising the ...

  6. Improving the Hydraulic Efficiency of Centrifugal Pumps through Computational Fluid Dynamics Based Design optimization

    Directory of Open Access Journals (Sweden)

    Abdellah Ait moussa

    2014-08-01

    Full Text Available The design and optimization of turbo machine impellers such as those in pumps and turbines is a highly complicated task due to the complex three-dimensional shape of the impeller blades and surrounding devices. Small differences in geometry can lead to significant changes in the performance of these machines. We report here an efficient numerical technique that automatically optimizes the geometry of these blades for maximum performance. The technique combines, mathematical modeling of the impeller blades using non-uniform rational B-spline (NURBS, Computational fluid dynamics (CFD with Geometry Parameterizations in turbulent flow simulation and the Globalized and bounded Nelder-Mead (GBNM algorithm in geometry optimization.

  7. A Neural Network Based MPPT Technique Controller for Photovoltaic Pumping System

    OpenAIRE

    Mohammed Yaichi; Mohammed-Karim Fellah; Abdelkrim Mammeri

    2014-01-01

    The article proposes a novel method using the artificial neural network (ANN) for the improvement of the performances of a photovoltaic system composed of a photovoltaic (PV) array, an inverter, a motor asynchronous and a centrifugal pump. For this type of system, different optimization strategies have been proposed to improve the over of the PV system efficiency, i.e. the PV generator is forced to operate at its maximum power point “MPPT”, generally, by the insertion of DC/DC boost converter...

  8. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    International Nuclear Information System (INIS)

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1→2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements

  9. Prediction of rotating stall within an impeller of a centrifugal pump based on spectral analysis of pressure and velocity data

    International Nuclear Information System (INIS)

    Experimental data, which was acquired in two centrifugal pumps and provided by Grundfos A/S, were analysed to determine if rotating stall could be detected from the velocity and pressure time series. The pressure data, which were uniformly acquired in time at high sample rates(10 kHz), were measured simultaneously in four adjacent di.user channels just downstream of the impeller outlet. The velocity data, which were non-uniformly sampled in time at fairly low rates(100 Hz to 3.5 kHz), were acquired either in or downstream of the impeller. Two di.erent methodologies were employed for detection of stall. The first method, which involved direct analysis of raw data, yielded qualitatively useful flow reversal information from the time series for the radial velocity. The second approach, which was based on power spectrum analysis of velocity and pressure data, could detect the onset and identify the frequency of rotating stall to a satisfactory extent in one of the two pumps. Nearly identical stall frequencies were observed in both velocity and pressure power spectra and this rotating stall phenomenon, which occurred at a very low frequency relative to the impeller speed, did not reveal any noticeable degree of sensitivity to the flow rate. In the other pump, where the available data was limited to velocity time series, the power spectrum analysis was successful in detecting stationary stall for a 6 bladed impeller but did not provide conclusive results for the existence of stall in the case of the 7 bladed impeller. Recommendations on the type of experimental data required for accurate detection of stall are provided based upon the present study

  10. Primary vertex reconstruction based on the Kalman filter technique at BESIII

    International Nuclear Information System (INIS)

    Primary vertex reconstruction is crucial to estimate the beam profile in collision experiments. We study the principle of an iterative process, called the Kalman filter method, and apply it to primary vertex reconstruction at BESIII. A Newton procedure to find the zero point of the distance function's gradient is used for primary vertex finding in 3-dimensional space. Results are obtained based on raw data at BESIII. (authors)

  11. Modelica-based modeling and simulation of a twin screw compressor for heat pump applications

    International Nuclear Information System (INIS)

    A new twin screw compressor has been developed by SRM (Svenska Rotor Maskiner) for use in a new high temperature heat pump using water as refrigerant. This article presents a mathematical model of the thermodynamic process of compression in twin screw compressors. Using a special discretization method, a transient twin screw compressor model has been developed using Modelica in order to study the dry compression cycle of this machine at high temperature levels. The pressure and enthalpy evolution in the control volumes of the model are calculated as a function of the rotational angle of the male rotor using energy and continuity equations. In addition, associated processes encountered in real machines such as variable fluid leakages, water injection and heat losses are modeled and implemented in the main compressor model. A comparison is performed using the model developed, demonstrating the behavior of the compressor and the evolution of its different parameters in different configurations with and without water injection. This comparison shows the need for water injection to avoid compressor failure and improve its efficiency. -- Highlights: • Difficulties related to the compressor limit the development of a high temperature heat pump using water as refrigerant. • A new water vapor double screw compressor has been developed to overcome compression problems. • A dynamic model of this compressor has been developed and simulated using Modelica. • The behavior of the compressor has been identified all along the compression cycle and efficiencies have been calculated

  12. Analysis of a 10 megawatt space-based solar-pumped neodymium laser system

    Science.gov (United States)

    Kurweg, U. H.

    1984-01-01

    A ten megawatt solar-pumped continuous liquid laser system for space applications is examined. It is found that a single inflatable mirror of 434 m diameter used in conjunction with a conical secondary concentrator is sufficient to side pump a liquid neodymium lasant in an annular tube of 6 m length and 1 m outer and 0.8 m inner diameter. About one fourth of intercepted radiation converging on the laser tube is absorbed and one fifth of this radiation is effective in populating the upper levels. The liquid lasant is flowed through the annular laser cavity at 1.9 m/s and is cooled via a heat exchanger and a large radiator surface comparable in size to the concentrating mirror. The power density of incident light within the lasant of approximately 68 watt/cu cm required for cw operation is exceeded in the present annular configuration. Total system weight corresponds to 20,500 kg and is thus capable of being transported to near Earth orbit by a single shuttle flight.

  13. Numerical simulation on pressure fluctuation of reactor coolant pump with complex impeller based on CFD technique

    International Nuclear Information System (INIS)

    In order to decrease pressure fluctuation of the reactor coolant pump under different conditions, three different inlet diameters of short blade of the reactor coolant pump were compared using numerical simulation, and the results show that the change of flow or inlet diameter of short blade does not change the dominant frequency of impeller. The high frequency of the suction side of blade gradually decreases and the high frequency of the pressure face gradually increases with the increase of inlet diameter of short blade. The pressure fluctuation amplitude of different inlet diameters of short blade with small flow is large. The wave energy of each monitoring point in the low frequency region and the high frequency region on the suction side of blade is significantly larger than that of the pressure face in the design condition. The band width of the low frequency region and wave energy of the high frequency region of monitoring points near the suction side of blade significantly increase at large flow fluctuation. The fluctuation amplitude of monitoring points near the pressure face of the blade has a large increase. The pulsation amplitude of each monitoring point near the suction side of the short blade is significantly higher than that of the long blade. The comprehensive analysis shows that when the inlet diameter of the short blade is 0.72D2, the pressure fluctuation in a variety of conditions reaches minimum. (authors)

  14. A graphene-based passively Q-switched Ho:YAG laser in-band pumped by a diode-pumped Tm:YLF solid-state laser

    International Nuclear Information System (INIS)

    We report the first demonstration of a Ho:YAG (yttrium aluminum garnet) solid-state laser passively Q-switched via a graphene saturable absorber. The Ho:YAG laser was in-band pumped by a continuous wave diode-pumped Tm:YLF (yttrium lithium fluoride) laser. Double-layer graphene grown by chemical vapor deposition and transferred onto a thin quartz plate was fabricated as the saturable absorber. We observed basically stable Q-switched laser pulses at the center wavelength of 2096.5 nm with the shortest pulse width of 632 ns, a repetition rate of 43 kHz, and the single-pulse energy of 13.3 μJ. Our results illustrate that graphene can be used well as a saturable absorber in a Ho-doped solid-state laser at 2 μm wavelength. (paper)

  15. High-power picosecond regenerative amplifier based on CW diode side-pumped Nd:YAG with high beam quality

    Institute of Scientific and Technical Information of China (English)

    Hua Lin; Jinfeng Li; Jinping He; Xiaoyan Liang

    2011-01-01

    @@ A compact high-power picosecond regenerative amplifier based on continuous wave(CW) diode sidepumped Nd:YAG is demonstrated.Average power of 8.8 W is achieved at,a repetition rate of 5 kHz at a wavelength of 1064 nm with a pulse duration of 28 ps,corresponding to a pulse energy of 1.76 mJ and a peak power of 62.9 MW.%A compact high-power picosecond regenerative amplifier based on continuous wave (CW) diode side-pumped Nd:YAG is demonstrated. Average power of 8.8 W is achieved at.a repetition rate of 5 kHz at a wavelength of 1064 nm with a pulse duration of 28 ps, corresponding to a pulse energy of 1.76 mJ and a peak power of 62.9 MW. The beam quality is close to the diffraction limit with M2x - 1.24, M2y = 1.03. To the best of our knowledge, this is the highest pulse energy obtained from a CW diode pumped Nd:YAG picosecond regenerative amplifier.

  16. Fiber-laser-based, green-pumped, picosecond optical parametric oscillator using fan-out grating PPKTP.

    Science.gov (United States)

    Chaitanya Kumar, S; Parsa, S; Ebrahim-Zadeh, M

    2016-01-01

    We report a stable, Yb-fiber-laser-based, green-pumped, picosecond optical parametric oscillator (OPO) for the near-infrared based on periodically poled potassium titanyl phosphate (PPKTP) nonlinear crystal, using fan-out grating design and operating near room temperature. The OPO is continuously tunable across 726-955 nm in the signal and 1201-1998 nm in the idler, resulting in a total signal plus idler wavelength coverage of 1026 nm by grating tuning at a fixed temperature. The device generates up to 580 mW of average power in the signal at 765 nm and 300 mW in the idler at 1338 nm, with an overall extraction efficiency of up to 52% and a pump depletion >76%. The extracted signal at 765 nm and idler at 1746 nm exhibit excellent passive power stability better than 0.5% and 0.8% rms, respectively, over 1 h with good beam quality in TEM00 mode profile. The output signal pulses have a Gaussian temporal duration of 13.2 ps, with a FWHM spectral bandwidth of 3.4 nm at 79.5 MHz repetition rate. Power scaling limitations of the OPO due to the material properties of PPKTP are studied. PMID:26696156

  17. Children Literature Based Program for Developing EFL Primary Pupils' Life Skills and Language Learning Strategies

    Science.gov (United States)

    Abdelhalim, Safaa M.

    2015-01-01

    This study examines the effectiveness of a proposed English language program based on integrating two forms of children literature, mainly short stories and songs, in developing the needed life skills and language learning strategies of primary school students. Besides, it emphasized the importance of providing EFL fifth year primary students with…

  18. Effectiveness of School-Based Bullying Intervention Programs in Primary School

    Science.gov (United States)

    Dogini, Eric U.

    2012-01-01

    Bullying behavior has reached pandemic proportions and is a growing concern in primary school. Most intervention programs in primary school are focused on bullying prevention or principally on the behavior of the bully. The purpose of this study was to explore whether a school-based bullying intervention program is an effective method for reducing…

  19. SHINE Vacuum Pump Test Verification

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Gregg A; Peters, Brent

    2013-09-30

    Normetex pumps used world-wide for tritium service are no longer available. DOE and other researchers worldwide have spent significant funds characterizing this pump. Identification of alternate pumps is required for performance and compatibility with tritium gas. Many of the pumps that could be used to meet the functional performance requirements (e.g. pressure and flow conditions) of the Normetex pump have features that include the use of polymers or oils and greases that are not directly compatible with tritium service. This study assembles a test system to determine the flow characteristics for candidate alternate pumps. These tests are critical to the movement of tritium through the SHINE Tritium Purification System (TPS). The purpose of the pump testing is two-fold: (1) obtain baseline vacuum pump characteristics for an alternate (i.e. ''Normetex replacement'') pump intended for use in tritium service; and (2) verify that low pressure hydrogen gas can be transported over distances up to 300 feet by the candidate pumps. Flow rates and nominal system pressures have been identified for the SHINE Mo-99 production process Tritium Purification System (TPS). To minimize the line sizes for the transfer of low pressure tritium from the Neutron Driver Accelerator System (NDAS) to the primary processing systems in the TPS, a ''booster'' pump has been located near the accelerator in the design. A series of pump tests were performed at various configurations using hydrogen gas (no tritium) to ensure that this concept is practical and maintains adequate flow rates and required pressures. This report summarizes the results of the tests that have been performed using various pump configurations. The current design of the Tritium Purification System requires the ''booster'' pump to discharge to or to be backed by another vacuum pump. Since Normetex pumps are no longer manufactured, a commercially available Edwards

  20. SHINE Vacuum Pump Test Verification

    International Nuclear Information System (INIS)

    Normetex pumps used world-wide for tritium service are no longer available. DOE and other researchers worldwide have spent significant funds characterizing this pump. Identification of alternate pumps is required for performance and compatibility with tritium gas. Many of the pumps that could be used to meet the functional performance requirements (e.g. pressure and flow conditions) of the Normetex pump have features that include the use of polymers or oils and greases that are not directly compatible with tritium service. This study assembles a test system to determine the flow characteristics for candidate alternate pumps. These tests are critical to the movement of tritium through the SHINE Tritium Purification System (TPS). The purpose of the pump testing is two-fold: (1) obtain baseline vacuum pump characteristics for an alternate (i.e. ''Normetex replacement'') pump intended for use in tritium service; and (2) verify that low pressure hydrogen gas can be transported over distances up to 300 feet by the candidate pumps. Flow rates and nominal system pressures have been identified for the SHINE Mo-99 production process Tritium Purification System (TPS). To minimize the line sizes for the transfer of low pressure tritium from the Neutron Driver Accelerator System (NDAS) to the primary processing systems in the TPS, a ''booster'' pump has been located near the accelerator in the design. A series of pump tests were performed at various configurations using hydrogen gas (no tritium) to ensure that this concept is practical and maintains adequate flow rates and required pressures. This report summarizes the results of the tests that have been performed using various pump configurations. The current design of the Tritium Purification System requires the ''booster'' pump to discharge to or to be backed by another vacuum pump. Since Normetex pumps are no longer manufactured, a commercially available Edwards scroll pump will be used to back the booster pump. In this

  1. Mindfulness-Based Stress Reduction (MBSR) for Primary School Teachers

    Science.gov (United States)

    Gold, Eluned; Smith, Alistair; Hopper, Ieuan; Herne, David; Tansey, Glenis; Hulland, Christine

    2010-01-01

    Stress within the teaching profession has a negative impact on the health and well-being of individual teachers and on retention and recruitment for the profession as a whole. There is increasing literature to suggest that Mindfulness is a useful intervention to address a variety of psychological problems, and that Mindfulness-Based Stress…

  2. A new waste heat district heating system with combined heat and power (CHP) based on ejector heat exchangers and absorption heat pumps

    International Nuclear Information System (INIS)

    A new waste heat district heating system with CHP based on ejector heat exchangers and absorption heat pumps (DH-EHE) is presented to decrease heating energy consumption of existing CHP systems by recovering waste heat of exhausted steam from a steam turbine, which could also increase heat transmission capacity of the primary heating network (PHN) by decreasing temperature of the return water of existing PHN. A new ejector heat exchanger based on ejector refrigeration cycle is invented to decrease temperature of the return water of PHN to 30 °C under the designed case. DH-EHE is analyzed in terms of laws of thermodynamics and economics. Compared to conventional district heating systems with CHP (CDH), DH-EHE can decrease consumption of steam extracted from a steam turbine by 41.4% and increase heat transmission capacity of the existing PHN by 66.7% without changing the flow rate of circulating water. The heating cost of DH-EHE is 8.62 ¥/GJ less than that of CDH. Compared to CDH, the recovery period of additional investment of DH-EHE is about two years. DH-EHE shows better economic and environmental benefits, which is promising for both district heating systems for long-distance heat transmission and waste heat district heating systems. - Highlights: • Heating capacity of this new heating system increases by 41% by waste heat recovery. • Temperature of return water of the primary heating network can be reduced to 30 °C. • Heating cost of new heating system is 8.62¥/GJ less than that of conventional one. • The recovery period of additional investment of new heating system is about 2 years. • This new heating system shows better economic and environmental benefits

  3. Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hudon, K.; Sparn, B.; Christensen, D.; Maguire, J.

    2012-02-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. Laboratory results demonstrate the efficiency of this technology under most of the conditions tested and show that differences in control schemes and design features impact the performance of the individual units. These results were used to understand current model limitations, and then to bracket the energy savings potential for HPWH technology in various US climate regions. Simulation results show that HPWHs are expected to provide significant energy savings in many climate zones when compared to other types of water heaters (up to 64%, including impact on HVAC systems).

  4. Computer-based pump inservice test program at San Onofre Nuclear Generating Station

    International Nuclear Information System (INIS)

    Pump inservice test (IST) data is intended to provide documentation of pressure boundary integrity and to assess operational readiness during its service life. In most cases, the official paper records of the final, single value test results are the only documents retained. This 'snapshot' approach focuses on the immediate results and all but ignores evaluation of equipment condition trends. This system satisfies regulatory requirements and is of limited usefulness for engineering analysis and equipment condition monitoring. The use of computers, in conjunction with specialized software and digital data collectors, to perform ISTs and archive data greatly enhances the information collected from these tests. In addition to improving both the quantity and quality of engineering data obtained, it drastically reduces the potential for human error

  5. Pump-limited, 203 W, single-frequency monolithic fiber amplifier based on laser gain competition.

    Science.gov (United States)

    Zeringue, Clint; Vergien, Christopher; Dajani, Iyad

    2011-03-01

    We present high power results of a Yb-doped fiber amplifier seeded with a combination of broad and single-frequency laser signals. This two-tone concept was used in conjunction with externally applied or intrinsically formed thermal gradients to demonstrate combined stimulated Brillouin scattering suppression in a copumped monolithic, polarization-maintaining (PM) fiber. Depending on the input parameters and the thermal gradient, the output power of the single-frequency signal ranged from 80 to 203 W with slope efficiencies from 70% to 80%. The 203 W amplifier was pump limited and is, to the best of our knowledge, the highest reported in the literature for monolithic, PM single-frequency fiber amplifiers. PMID:21368926

  6. Secondary access based on sensing and primary ARQ feedback in spectrum sharing systems

    KAUST Repository

    Hamza, Doha R.

    2012-04-01

    In the context of primary/secondary spectrum sharing, we propose a randomized secondary access strategy with access probabilities that are a function of both the primary automatic repeat request (ARQ) feedback and the spectrum sensing outcome. The primary terminal operates in a time slotted fashion and is active only when it has a packet to send. The primary receiver can send a positive acknowledgment (ACK) when the received packet is decoded correctly. Lack of ARQ feedback is interpreted as erroneous reception or inactivity. We call this the explicit ACK scheme. The primary receiver may also send a negative acknowledgment (NACK) when the packet is received in error. Lack of ARQ feedback is interpreted as an ACK or no-transmission. This is called the explicit NACK scheme. Under both schemes, when the primary feedback is interpreted as a NACK, the secondary user assumes that there will be retransmission in the next slot and accesses the channel with a certain probability. When the primary feedback is interpreted as an ACK, the secondary user accesses the channel with either one of two probabilities based on the sensing outcome. Under these settings, we find the three optimal access probabilities via maximizing the secondary throughput given a constraint on the primary throughput. We compare the performance of the explicit ACK and explicit NACK schemes and contrast them with schemes based on either sensing or primary ARQ feedback only. © 2012 IEEE.

  7. Hydraulic performance improvement of the bidirectional pit pump installation based on CFD

    Science.gov (United States)

    Chen, H. X.; Zhou, D. Q.

    2013-12-01

    At present, the efficiency of bidirectional pit pump installation with lift under 2m is still low because of lack of research on it in the past. In the paper, the CFD numerical method and experimental test were applied to study flow characteristic of bidirectional pit pump installation under positive and reverse condition. Through changing airfoil type and position of blade and stay vane, the comprehensive performance of improved model were obtained by calculating many different models. The results showed that when improved model is obtained with type A runner with 4 blades that is 0.7D away from pit exit and unsymmetrical guide vane 0.25dh which away from the impeller outlet, and the flow pattern of the improved solution is steady with high efficiency. Compared with the original scheme, the efficiency of positive and reverse design condition reach to 67.23% and 58.32% respectively, which is increased 6% more than original model on the design condition and 5% on the optimum operating condition, and it achieved the purpose of improvement. According to the runner blade angle of the optimization solution, model synthetic characteristic curve was drawn and internal flow field characteristics was analyzed under optimal positive and reverse conditions. The numerical calculation shows that owing to the lack of stay vane to recycle the energy in outlet runner chamber, the water flow regime is not steady enough in the outlet passage, and that is the main reason for lower efficiency at reverse condition than that at positive condition.

  8. Ultrafast pump-probe dynamics of iron oxide based earth pigments for applications to ancient pottery manufacture

    Science.gov (United States)

    Villafana, Tana E.; Brown, William; Warren, Warren S.; Fischer, Martin

    2015-06-01

    We demonstrate that ultrafast pump-probe microscopy provides unique dynamics for natural iron oxide and iron hydroxide earth pigments, despite their chemical similarity. First, we conducted a pump-probe spectroscopy study on heat-treated hematite (the pure red iron oxide mineral) and found the pump-probe dynamics to be temperature dependent. Second, we investigated pottery fired under known conditions and observed firing dependent pump-probe dynamics. Finally, we imaged a New World potshard from the North Carolina Museum of Art. Our results indicate that pump-probe microscopy could be a useful tool in elucidating pottery manufacture.

  9. Design of Pumps for Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard

    1999-01-01

    This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid...

  10. Jet Pump

    OpenAIRE

    Wærp, Nils Petter

    2010-01-01

    The aim of this project is to investigate how an artificial lift method in the oil industry works,and to compare its performance with other pump systems. Jet pumps are initially used in the oil industry for artificial lift and thus in order to do so one needs a good understanding of themechanics to predict the jet pumps’ performance. The project will begin with a review of how the jet pump operates, aiming to give the reader an insight and overview into the field of an artificial lift method....

  11. Course and outcome of eating disorders in a primary care-based cohort.

    OpenAIRE

    Son, G.E. van; Hoeken, D. van; Furth, E.F. van; Donker, G A; Hoek, H.W.

    2010-01-01

    OBJECTIVE: To study the course and outcome of patients with eating disorder detected in primary care. METHOD: General practitioners (GP's) provided information on the course and outcome of eating disorders in patients (n = 147) diagnosed with anorexia nervosa (AN) or bulimia nervosa (BN) identified during a Dutch nationwide primary care-based incidence study. The research team determined the outcome based on the data provided by the GP's. The mean duration of the follow-up was 4.8 years. RESU...

  12. Primary Syphilis

    Science.gov (United States)

    ... and rashes clinical tools newsletter | contact Share | Primary Syphilis Information for adults A A A This image ... ulcer with a red base, typical of primary syphilis. Overview Primary syphilis is a disease caused by ...

  13. Fiber optical parametric oscillator based on photonic crystal fiber pumped with all-normal-dispersion mode-locked Yb:fiber laser

    International Nuclear Information System (INIS)

    We demonstrate a cost effective, linearly tunable fiber optical parametric oscillator based on a home-made photonic crystal fiber pumped with a mode-locked ytterbium-doped fiber laser, providing linely tuning ranges from 1018 nm to 1038 nm for the idler wavelength and from 1097 nm to 1117 nm for the signal wavelength by tuning the pump wavelength and the cavity length. In order to obtain the desired fiber with a zero dispersion wavelength around 1060 nm, eight samples of photonic crystal fibers with gradually changed structural parameters are fabricated for the reason that it is difficult to accurately customize the structural dimensions during fabrication. We verify the usability of the fabricated fiber experimentally via optical parametric generation and conclude a successful procedure of design, fabirication, and verification. A seed source of home-made all-normal-dispersion mode-locked ytterbium-doped fiber laser with 38.57 ps pulsewidth around the 1064 nm wavelength is used to pump the fiber optical parametric oscillator. The wide picosecond pulse pump laser enables a larger walk-off tolerance between the pump light and the oscillating light as well as a longer photonic crystal fiber of 20 m superior to the femtosecond pulse lasers, resulting in a larger parametric amplification and a lower threshold pump power of 15.8 dBm of the fiber optical parametric oscillator. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  14. Electromagnetic pump

    International Nuclear Information System (INIS)

    The present invention provides an electromagnetic pump suitable to a recycling pump for liquid sodium as coolants of an FBR type reactor. Namely, a stator module of the electromagnetic pump of the present invention comprises a plurality of outer laminate iron core units and outer stator modules stacked alternately in the axial direction. With such a constitution, even a long electromagnetic pump having a large number of outer stator coils can be manufactured without damaging electric insulation of the outer stator coils. In addition, the inner circumferential surface of the outer laminate iron cores is urged and brought into contact with the outer circumferential surface of the outer duct by an elastic material. With such a constitution, Joule loss heat generated in the outer stator coils and internal heat generated in the outer laminate iron cores can be released to an electroconductive fluid flowing the inner circumference of the outer duct by way of the outer duct. (I.S.)

  15. Electrokinetic pump

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Kamlesh D. (Dublin, CA)

    2007-11-20

    A method for altering the surface properties of a particle bed. In application, the method pertains particularly to an electrokinetic pump configuration where nanoparticles are bonded to the surface of the stationary phase to alter the surface properties of the stationary phase including the surface area and/or the zeta potential and thus improve the efficiency and operating range of these pumps. By functionalizing the nanoparticles to change the zeta potential the electrokinetic pump is rendered capable of operating with working fluids having pH values that can range from 2-10 generally and acidic working fluids in particular. For applications in which the pump is intended to handle highly acidic solutions latex nanoparticles that are quaternary amine functionalized can be used.

  16. Phosphate-Buffered Saline-Based Nucleofection of Primary Endothelial Cells

    Science.gov (United States)

    Kang, Jinjoo; Ramu, Swapnika; Lee, Sunju; Aguilar, Berenice; Ganesan, Sathish Kumar; Yoo, Jaehyuk; Kalra, Vijay K.; Koh, Chester J.; Hong, Young-Kwon

    2009-01-01

    Although various non-viral transfection methods are available, cell-toxicity, low transfection efficiency and high-cost remain hurdles for in vitro gene delivery in cultured primary endothelial cells. Recently, unprecedented transfection efficiency for primary endothelial cells has been achieved due to the newly developed nucleofection technology that utilizes a combination of novel electroporation conditions and specific buffer components that stabilize the cells in the electrical field. Despite its superior transfection efficiency and cell viability, high cost of the technology has discouraged the cardiovascular researchers to liberally adopt this new technology. Here, we report that a phosphate-buffered saline (PBS)-based nucleofection method can be used for efficient gene delivery into primary endothelial cells and other types of cells. Comparative analyses of transfection efficiency and cell viability for primary arterial, venous, microvascular and lymphatic endothelial cells were performed by using PBS. Compared to the commercial buffers, PBS can support equally remarkable nucleofection efficiency to both primary and non-primary cells. Moreover, PBS-mediated nucleofection of siRNA showed more than 90% knockdown of the expression of target genes in primary endothelial cells. Together, we demonstrate that PBS can be an unprecedented economical alternative for the high-cost buffers for nucleofection of various primary and non-primary cells. PMID:19150324

  17. Adiabatic pumping through quantum dots

    International Nuclear Information System (INIS)

    A finite charge can be pumped through a mesoscopic system in the absence of an applied bias voltage by changing periodically in time some parameters of the system. If these parameters change slowly with respect to all internal time scales of the system, pumping is adiabatic. The scope of this work is to investigate adiabatic pumping through a quantum dot, in particular the influence of Coulomb interaction between electrons in the dot on the pumped charge. On one hand we develop a formalism based on Green's functions, in order to calculate the pumped charge from the weak-tunnel-coupling regime down to the Kondo regime. We extend our calculations to a system with a superconducting contact. On the other hand we use a systematic perturbation expansion for the calculation of the pumped charge, giving us the possibility to analyze processes which contribute to charge pumping and to highlight the important role of interaction-induced level renormalization. (orig.)

  18. Decentralized pump system Geniax with mini-pumps. From supply-based heating to a demand-based heating system; Dezentrales Pumpensystem Geniax mit Miniaturpumpen. Von der Angebotsheizung zur Bedarfsheizung

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2009-03-15

    The 'decentral pump system' by Wilo provides heating on demand instead of conventional heating with a central pump and throttle control. Each heating panel is provided with the necessary volume of heating water by a miniature pump. For the fitter, this means that time-consuming manual hydraulic control is no longer necessary. The contribution explains details of the innovative technology, its saving potential, and aspects that must be considered during projecting and assembly. (orig./GL)

  19. Studies of diode-pumped solid-state lasers based on Nd:KGW and Nd:YAG

    International Nuclear Information System (INIS)

    The experimental part of the thesis was dedicated to the studies of diode-pumped solid- state lasers. it includes experiments with end-pumped continuous wave (CW) Nd-doped crystals. In particular, we have concentrated to Nd:KGW, a relatively new and not studied in the literature about the laser materials. We have performed some basics measurements of this material. A fibre bundle coupled laser diode array was used as a pump source. We have investigated two main optical arrangements for the pump, allowing operation in two regimes: 1- Low pump power operation using selected output power from a single of the fibre bundle. 2- high pump power operation using the total output power from the bundle. The main parameters of the cavities we use (e.g. the cavity mode and the pumping spot size), were determined using the matrix approach and the equations for the propagation of the Gaussian beams. The highest output power obtained in this work for Nd:KGW with a transverse electromagnetic (TEM00) single-mode, continuous (CW) operation, was 400 mW for 1700 mW pumping power from the diode laser. We present also data about the performance of a diode pumped Nd:YAG crystal. Our experiment shows that Nd:KGW is a promising material of low and medium pumping power levels. (Author)

  20. Nuclear-pumped lasers

    CERN Document Server

    Prelas, Mark

    2016-01-01

    This book focuses on Nuclear-Pumped Laser (NPL) technology and provides the reader with a fundamental understanding of NPLs, a review of research in the field, and exploration of large scale NPL system design and applications. Early chapters look at the fundamental properties of lasers, nuclear-pumping and nuclear reactions that may be used as drivers for nuclear-pumped lasers. The book goes on to explore the efficient transport of energy from the ionizing radiation to the laser medium and then the operational characteristics of existing nuclear-pumped lasers. Models based on Mathematica, explanations and a tutorial all assist the reader’s understanding of this technology. Later chapters consider the integration of the various systems involved in NPLs and the ways in which they can be used, including beyond the military agenda. As readers will discover, there are significant humanitarian applications for high energy/power lasers, such as deflecting asteroids, space propulsion, power transmission and mining....

  1. 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.

  2. Monitoring of Building Heating and Cooling Systems Based on Geothermal Heat Pump in Galicia (Spain

    Directory of Open Access Journals (Sweden)

    Franco D.

    2012-10-01

    Full Text Available In November 2009 was signed an agreement between Galicia’s Government and EnergyLab to develop a project related with the geothermal heatpumps (hereafter, GSHP technology. That project consisted in replacing the existing thermal equipment generators (diesel boilers and air-water heat pumps by GSHP systems in representative public buildings: two nursery schools, a university library, a health centre and a residential building. This new systems will reach the demands of existing heating, cooling and domestic hot water (hereafter, DHW. These buildings can serve as examples of energy and economic savings that can offer this technology. We will show detailed analysis of the GSHP facilities monitored, since the starting-up of them. Which includes: COP’s, EER’s, energy consumption, operating costs, operation hours of the system, economic and emissions comparative, geothermal exchange evolution graphs, environmental conditions evolution graphs (temperature and demands, etc. The results presented show an example of the important benefits of the GSHP technology and the significant savings that can offer its implementation for heating, cooling and DHW production.

  3. The effectiveness of groundwater pumping as a restoration technology

    International Nuclear Information System (INIS)

    An in-depth analysis of the effectiveness of pumping groundwater for aquifer restoration was conducted based on: (1) performance records for 16 sites where pumping with the objective of aquifer restoration has been implemented for periods of 2 to 12 years, and (2) recent theoretical and modeling studies. The reduction of aquifer concentrations is the primary indicator of effectiveness of groundwater extraction. However, other indicators of effectiveness such as plume containment, mass reduction, and achievement of specific cleanup goals were also components of the evaluation. Based on our review of performance records and recent theoretical studies, the following can be concluded regarding the use of groundwater pumping for aquifer restoration: (1) Pumping is effective for contaminant mass reduction, plume containment and extraction of groundwater for point-of-use treatment. Its use for attaining these objectives should be encouraged. (2) Groundwater pumping is ineffective for restoring aquifers to health-based levels. This reality needs to be explicitly recognized by regulators. (3) The primary contributors to the ineffectiveness of pumping in meeting cleanup goals are the time-dependent decrease in the rate of desorption of contaminants from contaminated soils and the existence of immobile contaminants either in the non-aqueous phase or trapped in zones of low permeability. (4) Remedial time frames of 2 years to 30 years were predicted at the sites reviewed. Regulators currently maintain that 20 to 40 years may be needed to reach health-based cleanup goals. However, recent modeling studies estimate pump and treat time frames of 100 to 1000 years. 22 refs., 5 figs., 4 tabs

  4. The role of mental health in primary prevention of sexual and gender-based violence

    Directory of Open Access Journals (Sweden)

    Aník Gevers

    2014-09-01

    Full Text Available In this short communication, we assert that mental health has a crucial role in the primary prevention of sexual and gender-based violence (SGBV. However, we found that most research and practice to date has focused on the role of mental health post-violence, and SGBV primary prevention is relying on public health models that do not explicitly include mental health. Yet, key concepts, processes, and competencies in the mental health field appear essential to successful SGBV primary prevention. For example, empathy, self-esteem, compassion, emotional regulation and resilience, stress management, relationship building, and challenging problematic social norms are crucial. Furthermore, competencies such as rapport building, group processing, emotional nurturing, modelling, and the prevention of vicarious trauma among staff are important for the successful implementation of SGBV primary prevention programmes. SGBV primary prevention work would benefit from increased collaboration with mental health professionals and integration of key mental health concepts, processes, and skills in SGBV research.

  5. The role of mental health in primary prevention of sexual and gender-based violence.

    Science.gov (United States)

    Gevers, Aník; Dartnall, Elizabeth

    2014-01-01

    In this short communication, we assert that mental health has a crucial role in the primary prevention of sexual and gender-based violence (SGBV). However, we found that most research and practice to date has focused on the role of mental health post-violence, and SGBV primary prevention is relying on public health models that do not explicitly include mental health. Yet, key concepts, processes, and competencies in the mental health field appear essential to successful SGBV primary prevention. For example, empathy, self-esteem, compassion, emotional regulation and resilience, stress management, relationship building, and challenging problematic social norms are crucial. Furthermore, competencies such as rapport building, group processing, emotional nurturing, modelling, and the prevention of vicarious trauma among staff are important for the successful implementation of SGBV primary prevention programmes. SGBV primary prevention work would benefit from increased collaboration with mental health professionals and integration of key mental health concepts, processes, and skills in SGBV research. PMID:25226417

  6. A primary care-based health needs assessment in inner city Dublin.

    LENUS (Irish Health Repository)

    O'Kelly, C M

    2012-02-01

    BACKGROUND: In 2001, a primary care-based health needs assessment (HNA) in South Inner City of Dublin identified high levels of morbidity and widespread and frequent use of primary care and specialist hospital services as particular concerns. AIMS: This study aims to determine the primary care health needs of a local community, from the perspective of service users and service providers. METHODS: A similar methodology to our 2001 HNA was adopted, involving semi-structured interviews with a convenience sample of patients attending two general practices and key informants regarding local health issues and health service utilisation. RESULTS: High levels of morbidity and chronic illness were found. A correlation between the local environment and ill-health was identified, as well as high utilisation of primary care services in the area. CONCLUSION: The establishment of a Primary Care Team would begin to address the health needs of the community.

  7. Preliminary training of a self-pumped loop phase-conjugate mirror based on a photorefractive crystal

    International Nuclear Information System (INIS)

    It is shown by the example of a loop self-pumped phase-conjugate (SPPC) mirror based on a photorefractive crystal (PRC) BaTiO3 that formation of a phase-conjugate (PC) wave in a SPPC mirror can be considerably accelerated by using a preliminary training of the mirror. For this purpose, it is necessary to direct preliminary an auxiliary (training) optical field on the SPPC mirror, which contains some information on the properties of the input signal whose wave front will be conjugated later. This procedure provides the writing of static refractive-index gratings in the PRC already at the training stage. The presence of these gratings ensures a much more rapid (by 6-20 times) production of volume refractive-index gratings required for the efficient conjugation of the signal radiation. Several variants of static and dynamic SPPC mirror training procedures are simulated and their efficiencies are compared. (nonlinear optical phenomena)

  8. Quasi-three-level thin-disk laser at 1024 nm based on diode-pumped Yb:YAG crystal

    International Nuclear Information System (INIS)

    We present for the first time, to the best of our knowledge, a Yb:YAG laser operating in a continuous wave (CW) on the quasi-three-level laser at 1024 nm, based on the 2F5/2 – 2F7/2 transition, generally used for a 1030 nm emission. The use of a pump module with 16 passes through the crystal allowed the realization of a Yb:YAG thin-disk laser with 370 mW of CW output power at 1024 nm. Moreover, intracavity second-harmonic generation (SHG) has also been achieved with a power of 45 mW at 512 nm by using a LiB3O5 (LBO) nonlinear crystal

  9. Spin exchange optical pumping based polarized 3He filling station for the Hybrid Spectrometer at the Spallation Neutron Source

    International Nuclear Information System (INIS)

    The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60° horizontal and 15° vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized 3He filling station based on the spin exchange optical pumping method. It is designed to supply polarized 3He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the 3He pressure with respect to the scattered neutron energies. The depolarized 3He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

  10. Experimental Realization of a Quantum Spin Pump

    DEFF Research Database (Denmark)

    Watson, Susan; Potok, R.; M. Marcus, C.;

    2003-01-01

    We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin-dependent by the...... application of an in-plane Zeeman field. Spin currents are measured by placing the pump in a focusing geometry with a spin-selective collector....

  11. Computer based I and C for primary sodium systems of PFBR

    International Nuclear Information System (INIS)

    Prototype Fast Breeder Reactor is in the advanced stage of construction at Kalpakkam, India. Primary sodium circuit is used to transfer the heat generated from the core to secondary sodium circuit which in turn transfers the heat to steam water circuit. Primary sodium circuit consists of three different circuit namely primary sodium main, fill and drain and purification circuit. Instrumentation and Control signals of primary sodium circuits are classified as Safety Class 2 (SC2). Versa Module Europa bus based Real Time Computers (RTC) are used to process SC2 signals. Hot standby architecture consisting of dual redundant RTC system with switch over logic system is the configuration adopted to achieve fault tolerance. Well defined software development methodology was followed with independent verification and validation (V and V) of deliverables at each stage. Static analysis and black box based system integration testing was carried out. Demonstration of system performance to independent V and V committee was accomplished. (author)

  12. Erectile dysfunction among diabetic patients in Saudi Arabia: A hospital-based primary care study

    Directory of Open Access Journals (Sweden)

    Yousef A Al-Turki

    2007-01-01

    Conclusions: Complete (severe and partial erectile dysfunction was quite common among adult diabetic patients in a hospital-based primary care setting in Saudi Arabia. It is important for primary care physicians to diagnose erectile dysfunction in diabetic patients, and to counsel them early, as most patients are hesitant to discuss their concern during a consultation. Further studies are recommended to evaluate the effect of other risk factors on erectile dysfunction in diabetic patients.

  13. What Do Primary Students Say about School-Based Social Work Programmes?

    Science.gov (United States)

    Testa, Doris

    2014-01-01

    This article focuses on primary school children's experiences of school-based social work programmes. These students, aged between 6 and 11, and drawn from a student population comprising 28 different cultural backgrounds and from low socio-economic backgrounds, participated in a case study that researched a school-based social work…

  14. School-Based Primary School Sexuality Education for Migrant Children in Beijing, China

    Science.gov (United States)

    Liu, Wenli; Su, Yufen

    2014-01-01

    In May 2007, Beijing Normal University launched a programme of school-based sexuality education for migrant children in Xingzhi Primary School in Beijing. Over the past seven years, the project team has developed a school-based sexuality education curriculum using the "International Technical Guidance on Sexuality Education" published by…

  15. Ultra-broadband Superradiant Pulses from Femtosecond Laser Pumped InP based Quantum Well Laser Diode

    Science.gov (United States)

    Liu, Jingjing

    Laser techniques, such as gain / Q switching, mode-locking, have successfully overcome the energy restriction of gain clamping in the stead-state operated lasers, and allowed the generation of giant pulses with short pulse durations. However, gain saturation further limits the amount of stored energy in a gain medium, and therefore limits the possible maximum pulse energy obtained by laser techniques. Here we circumvent both gain clamping and the capacity limitation of energy storage by operating the double-quantum-well laser diode chips on ultrafast gain-switching model using femtosecond (fs) laser pulses as the optical pump. The advantage of our pumping approach is that the fs pulse can instantly produce a very large number of carriers, and therefore enable the formation of non-equilibrium coherent e-h BCS-like condensate state in a large energy region from the lowest QW subband edges to the highest subband and then obtain the ultra-broadband superradiant pulses. Superradiance (SR) or the coherent spontaneous emission is not a new quantum optics phenomenon, which has been proposed in 1954 by R. Dicke, even earlier than the invention of laser. It is famous as by its ultrashort duration, high peak power, high coherence and high timing jitter. Recently, femtosecond SR pulses have been generated from semiconductors. This investigation has revived both theoretical and experimental studies of SR emission. In this thesis, we have demonstrated the generation of intense, delayed SR pulses from the InP based double quantum well laser diode at room temperature. The 1040 nm femtosecond laser was applied as the optical pumping source, and when the pump power is high enough, the cooperative recombination of e-h pairs from higher order quantum energy levels can occur to generate SR bursts earlier than the cooperative emission from the lower quantum energy levels. Then, ultra-broadband TM polarized SR pulses have been firstly generated at room temperature. Our experiments also

  16. Investigation of practical data on primary energy consumption and climate-relevant gaseous emissions of modern heat pump systems; Untersuchung von Praxisdaten zum Primaerenergiebedarf und den Treibhausgasemissionen von modernen Waermepumpen

    Energy Technology Data Exchange (ETDEWEB)

    Heidelck, R.; Laue, H.J.

    1999-04-01

    Primary energy consumption and CO{sub 2} emissions of heat pump systems were investigated on the basis of measurements and simulations. A gas heating system with high-efficiency boiler was used as reference system as it is the most advanced fossil-fuel heating technology in terms of fuel consumption and CO{sub 2} emissions. [German] Ziel der Studie ist es, moderne Heizungssysteme im Hinblick auf den Primaerenergiebedarf und die Treibhausgasemissionen zu untersuchen. Im Mittelpunkt der Untersuchungen stehen dabei Waermepumpen-Heizungsanlagen. Es wurden dazu Messdaten der energetischen Eigenschaften von Waermepumpenanlagen gesammelt und ausgewertet. Zusaetzlich werden Ergebnisse von Simulationsrechnungen aus der Literatur hinzugezogen. Als Vergleichssystem zu Waermepumpenheizungsanlagen eignet sich am besten eine Gasbrennwert-Heizungsanlage, da sie aus Sicht niedriger CO{sub 2}-Emissionen und Brennstoffverbrauch den hoechsten Stand der Entwicklung der konventionellen, auf fossilen Energietraegern basierender Heiztechnik darstellt. (orig.)

  17. Fault Diagnosis of Plunger Pump in Truck Crane Based on Relevance Vector Machine with Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Wenliao Du

    2013-01-01

    Full Text Available Promptly and accurately dealing with the equipment breakdown is very important in terms of enhancing reliability and decreasing downtime. A novel fault diagnosis method PSO-RVM based on relevance vector machines (RVM with particle swarm optimization (PSO algorithm for plunger pump in truck crane is proposed. The particle swarm optimization algorithm is utilized to determine the kernel width parameter of the kernel function in RVM, and the five two-class RVMs with binary tree architecture are trained to recognize the condition of mechanism. The proposed method is employed in the diagnosis of plunger pump in truck crane. The six states, including normal state, bearing inner race fault, bearing roller fault, plunger wear fault, thrust plate wear fault, and swash plate wear fault, are used to test the classification performance of the proposed PSO-RVM model, which compared with the classical models, such as back-propagation artificial neural network (BP-ANN, ant colony optimization artificial neural network (ANT-ANN, RVM, and support vectors, machines with particle swarm optimization (PSO-SVM, respectively. The experimental results show that the PSO-RVM is superior to the first three classical models, and has a comparative performance to the PSO-SVM, the corresponding diagnostic accuracy achieving as high as 99.17% and 99.58%, respectively. But the number of relevance vectors is far fewer than that of support vector, and the former is about 1/12–1/3 of the latter, which indicates that the proposed PSO-RVM model is more suitable for applications that require low complexity and real-time monitoring.

  18. Smart Grid enabled heat pumps

    DEFF Research Database (Denmark)

    Carmo, Carolina; Detlefsen, Nina; Nielsen, Mads Pagh

    2014-01-01

    an empirical study in order to achieve a number of recommendations with respect to technology concepts and control strategies that would allow residential vapor-compression heat pumps to support large-scale integration of intermittent renewables. The analysis is based on data gathered over a period...... of up to 3 years for 283 residential heat pumps installed and operating in Denmark. The results are used to assess the flexibility of domestic heat pumps and their ability to follow production....

  19. Spin pumping through quantum dots

    OpenAIRE

    Rojek, Stephan; Governale, Michele; König, Jürgen

    2013-01-01

    We propose schemes for generating spin currents into a semiconductor by adiabatic or non-adiabatic pumping of electrons through interacting quantum dots. The appeal of such schemes lies in the possibility to tune the pumping characteristics via gate voltages that control the properties of the quantum dot. The calculations are based on a systematic perturbation expansion in the tunnel-coupling strength and the pumping frequency, expressed within a diagrammatic real-time technique. Special focu...

  20. Research on synchronous gear pump

    Institute of Scientific and Technical Information of China (English)

    LUAN Zhen-hui

    2010-01-01

    Based on a comprehensive analysis of the structure and existing problems of the gear pump, provided a structure principle of a synchronous gear pump. The discussions focused on the working principle, construction features and finite element analysis of the hydraulic gear. The research indicates that the new pump has such advantages as lower noise, better distributed flow and a high work pressure, and it can be widely used in hydraulic systems.

  1. Selection of Cluster Well Pumping Unit Wire Rope Based on Fuzzy Multi-Objective Decision-Making

    Science.gov (United States)

    Qu, Wentao; Wang, Yajuan; Kang, Xianzhi; Xi, Xiaopeng; Zou, Wei

    Influencing factors in cluster well pumping unit wire rope was analyzed corresponding index system. According to its characteristics, combined with fuzzy set theory, a multi-objective decision-making model of luster well pumping unit wire rope was set up, and the example of application was given to verify its feasibility.

  2. DIFFUSION PUMP

    Science.gov (United States)

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  3. Direct comparison of shot-to-shot noise performance of all normal dispersion and anomalous dispersion supercontinuum pumped with sub-picosecond pulse fiber-based laser

    Science.gov (United States)

    Klimczak, Mariusz; Soboń, Grzegorz; Kasztelanic, Rafał; Abramski, Krzysztof M.; Buczyński, Ryszard

    2016-01-01

    Coherence of supercontinuum sources is critical for applications involving characterization of ultrafast or rarely occurring phenomena. With the demonstrated spectral coverage of supercontinuum extending from near-infrared to over 10 μm in a single nonlinear fiber, there has been a clear push for the bandwidth rather than for attempting to optimize the dynamic properties of the generated spectrum. In this work we provide an experimental assessment of the shot-to-shot noise performance of supercontinuum generation in two types of soft glass photonic crystal fibers. Phase coherence and intensity fluctuations are compared for the cases of an anomalous dispersion-pumped fiber and an all-normal dispersion fiber. With the use of the dispersive Fourier transformation method, we demonstrate that a factor of 100 improvement in signal-to-noise ratio is achieved in the normal-dispersion over anomalous dispersion-pumped fiber for 390 fs long pump pulses. A double-clad design of the photonic lattice of the fiber is further postulated to enable a pump-related seeding mechanism of normal-dispersion supercontinuum broadening under sub-picosecond pumping, which is otherwise known for similar noise characteristics as modulation instability driven, soliton-based spectra.

  4. Direct comparison of shot-to-shot noise performance of all normal dispersion and anomalous dispersion supercontinuum pumped with sub-picosecond pulse fiber-based laser.

    Science.gov (United States)

    Klimczak, Mariusz; Soboń, Grzegorz; Kasztelanic, Rafał; Abramski, Krzysztof M; Buczyński, Ryszard

    2016-01-01

    Coherence of supercontinuum sources is critical for applications involving characterization of ultrafast or rarely occurring phenomena. With the demonstrated spectral coverage of supercontinuum extending from near-infrared to over 10 μm in a single nonlinear fiber, there has been a clear push for the bandwidth rather than for attempting to optimize the dynamic properties of the generated spectrum. In this work we provide an experimental assessment of the shot-to-shot noise performance of supercontinuum generation in two types of soft glass photonic crystal fibers. Phase coherence and intensity fluctuations are compared for the cases of an anomalous dispersion-pumped fiber and an all-normal dispersion fiber. With the use of the dispersive Fourier transformation method, we demonstrate that a factor of 100 improvement in signal-to-noise ratio is achieved in the normal-dispersion over anomalous dispersion-pumped fiber for 390 fs long pump pulses. A double-clad design of the photonic lattice of the fiber is further postulated to enable a pump-related seeding mechanism of normal-dispersion supercontinuum broadening under sub-picosecond pumping, which is otherwise known for similar noise characteristics as modulation instability driven, soliton-based spectra. PMID:26759188

  5. [Improved Response to 5-FU Using Dose Adjustment and Elastomeric Pump Selection Based on Monitoring of the 5-FU Level--A Case Report].

    Science.gov (United States)

    Muneoka, Katsuki; Shirai, Yoshio; Kanda, Junkichi; Sasaki, Masataka; Wakai, Toshifumi; Wakabayashi, Hiroyuki

    2015-10-01

    A 6 1-year-old man with unresectable multiple hepatic metastases after resection of sigmoid colon carcinoma was treated with irinotecan and infused 5-fluorouracil (5-FU) plus Leucovorin (FOLFIRI). Since the levels of tumor markers increased, the 5-FU dose was increased from 2,700 to 3,000 mg/m2 using a Jackson-type pump and an extended infusion time of 53 hours. The blood level of 5-FU was 507 ng/mL 16 hours after starting the infusion. The pump was then changed to a bottle-type pump with the same dose of 3,000 mg/m2. At 16 hours, the 5-FU level was 964.5 ng/mL. The areas under the concentration vs. time curve (AUC mg・h/L)were 21 and 44 mg・h/L for the Jackson- and bottle-type pumps, respectively. Owing to the development of Grade 3 stomatitis and hand-foot syndrome, 5-FU was reduced to 2,700 mg/m2 with a bottle-type pump. The AUC decreased to 27 mg・h/L, but the liver metastases were reduced and the adverse effects subsided to Grade 1. This case shows that individual dose adjustment of 5-FU to the appropriate AUC based on pharmacokinetic monitoring of the blood 5-FU level can improve the response, reduce adverse effects, and have a clinical benefit. PMID:26489552

  6. Predicting performance of a ground-source heat pump system using fuzzy weighted pre-processing-based ANFIS

    Energy Technology Data Exchange (ETDEWEB)

    Esen, Hikmet; Esen, Mehmet [Department of Mechanical Education, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey); Inalli, Mustafa [Department of Mechanical Engineering, Faculty of Engineering, Firat University, 23279 Elazig (Turkey); Sengur, Abdulkadir [Department of Electronic and Computer Science, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey)

    2008-12-15

    The goal of this work is to predict the daily performance (COP) of a ground-source heat pump (GSHP) system with the minimum data set based on an adaptive neuro-fuzzy inference system (ANFIS) with a fuzzy weighted pre-processing (FWP) method. To evaluate the effectiveness of our proposal (FWP-ANFIS), a computer simulation is developed on MATLAB environment. The comparison of the proposed hybridized system's results with the standard ANFIS results is carried out and the results are given in the tables. The efficiency of the proposed method was demonstrated by using the 3-fold cross-validation test. The statistical methods, such as the root-mean squared (RMS), the coefficient of multiple determinations (R{sup 2}) and the coefficient of variation (cov), are given to compare the predicted and actual values for model validation. The average R{sup 2} values is 0.9998, the average RMS value is 0.0272 and the average cov value is 0.7733, which can be considered as very promising. The data set for the COP of GSHP system available included 38 data patterns. The simulation results show that the FWP-based ANFIS can be used in an alternative way in these systems. The prediction results of the proposed structure were much better than the standard ANFIS results. Therefore, instead of limited experimental data found in the literature, faster and simpler solutions are obtained using hybridized structures such as FWP-based ANFIS. (author)

  7. Gallic acid-based indanone derivative interacts synergistically with tetracycline by inhibiting efflux pump in multidrug resistant E. coli.

    Science.gov (United States)

    Dwivedi, Gaurav Raj; Tiwari, Nimisha; Singh, Aastha; Kumar, Akhil; Roy, Sudeep; Negi, Arvind Singh; Pal, Anirban; Chanda, Debabrata; Sharma, Ashok; Darokar, Mahendra P

    2016-03-01

    The purpose of the present study was to study the synergy potential of gallic acid-based derivatives in combination with conventional antibiotics using multidrug resistant cultures of Escherichia coli. Gallic acid-based derivatives significantly reduced the MIC of tetracycline against multidrug resistant clinical isolate of E. coli. The best representative, 3-(3',4,'5'-trimethoxyphenyl)-4,5,6-trimethoxyindanone-1, an indanone derivative of gallic acid, was observed to inhibit ethidium bromide efflux and ATPase which was also supported by in silico docking. This derivative extended the post-antibiotic effect and decreased the mutation prevention concentration of tetracycline. This derivative in combination with TET was able to reduce the concentration of TNFα up to 18-fold in Swiss albino mice. This derivative was nontoxic and well tolerated up to 300 mg/kg dose in subacute oral toxicity study in mice. This is the first report of gallic acid-based indanone derivative as drug resistance reversal agent acting through ATP-dependent efflux pump inhibition. PMID:26658982

  8. One-to-six WDM multicasting of DPSK signals based on dual-pump four-wave mixing in a silicon waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua;

    2011-01-01

    We present WDM multicasting based on dual-pump four-wave mixing in a 3-mm long dispersion engineered silicon waveguide. One-to-six phase-preserving WDM multicasting of 10-Gb/s differential phase-shiftkeying (DPSK) data is experimentally demonstrated with bit-error rate measurements. All the six...

  9. A Case of Multiple Primary Tumors of the Anterior Skull Base

    OpenAIRE

    Lenarz, Minoo; Durisin, Martin; Becker, Hartmut; Brandis, Almuth; Lenarz, Thomas

    2007-01-01

    We report a case of synchronous olfactory bulb meningioma and undifferentiated carcinoma of the nose and paranasal sinuses that involved and destroyed the anterior skull base and mimicked intracranial invasion by a carcinoma. The heterogeneity of tissue types in the skull base gives rise to a diverse variety of benign and malignant neoplasms which have totally different prognoses. Synchronous development of benign and malignant primary tumors both originating from and involving the skull base...

  10. The Design of a Low Power Floating Gate Based Phase Frequency Detector and Charge Pump Implementation

    OpenAIRE

    Md. Monirul Islam; Ankit Shivhare

    2013-01-01

    A simple new architecture of phase frequency detector with low power and low phase noise is presented in this paper. The proposed phase frequency detector is based on floating gate, consist of 4 transistors including one floating gate pMOS and one floating gate nMOS constructed with two GDI (gate diffusion input) cells and maintain main characteristics of conventional phase frequency detector in 180 nm technology. Floating gate based methodology reduced the power of phase frequenc...

  11. Nurse led, primary care based antiretroviral treatment versus hospital care: a controlled prospective study in Swaziland

    Directory of Open Access Journals (Sweden)

    Bailey Kerry A

    2010-08-01

    Full Text Available Abstract Background Antiretroviral treatment services delivered in hospital settings in Africa increasingly lack capacity to meet demand and are difficult to access by patients. We evaluate the effectiveness of nurse led primary care based antiretroviral treatment by comparison with usual hospital care in a typical rural sub Saharan African setting. Methods We undertook a prospective, controlled evaluation of planned service change in Lubombo, Swaziland. Clinically stable adults with a CD4 count > 100 and on antiretroviral treatment for at least four weeks at the district hospital were assigned to either nurse led primary care based antiretroviral treatment care or usual hospital care. Assignment depended on the location of the nearest primary care clinic. The main outcome measures were clinic attendance and patient experience. Results Those receiving primary care based treatment were less likely to miss an appointment compared with those continuing to receive hospital care (RR 0·37, p p = 0·001. Those receiving primary care based, nurse led care were more likely to be satisfied in the ability of staff to manage their condition (RR 1·23, p = 0·003. There was no significant difference in loss to follow-up or other health related outcomes in modified intention to treat analysis. Multilevel, multivariable regression identified little inter-cluster variation. Conclusions Clinic attendance and patient experience are better with nurse led primary care based antiretroviral treatment care than with hospital care; health related outcomes appear equally good. This evidence supports efforts of the WHO to scale-up universal access to antiretroviral treatment in sub Saharan Africa.

  12. Effect of baseline gastrointestinal risk and use of proton pump inhibitors on frequency of discontinuation of aspirin for secondary cardiovascular prevention in United kingdom primary care.

    Science.gov (United States)

    Martín Merino, Elisa; Johansson, Saga; Nagy, Péter; García Rodríguez, Luis A

    2013-10-15

    For patients at high cardiovascular and high gastrointestinal (GI) risk, coprescription of a proton pump inhibitor (PPI) with low-dose aspirin is recommended. We aimed to quantify the extent to which low-dose aspirin discontinuation in patients at high cardiovascular risk is affected by PPI use and baseline GI risk. Patients aged 50 to 84 years who had evidence of ischemic heart disease or cardiovascular disease and who were new users of low-dose aspirin in 2000 to 2007 were identified using The Health Improvement Network (n = 35,604). Aspirin discontinuation was defined as a period of at least 90 days after completion of the last prescribed course during which no repeat prescription was issued. The incidence of low-dose aspirin discontinuation was 26.8 per 100 person-years (95% confidence interval [CI] 26.2 to 27.4). The age-, gender-, and indication-adjusted risk of aspirin discontinuation was 15% less among continuous PPI users than among PPI nonusers (hazard ratio [HR] 0.85, 95% CI 0.78 to 0.92); after further adjusting for number of coprescribed medications, the HR was 0.95 (95% CI 0.87 to 1.03). Continuous PPI use was associated with a reduced risk of aspirin discontinuation among patients at high GI risk (HR 0.83; 95% CI 0.74 to 0.93) but not among those at low GI risk (HR 1.08; 95% CI 0.96 to 1.21). In conclusion, among patients at high GI risk, concomitant users of aspirin and PPI showed a greater aspirin adherence than aspirin users not on PPI. Further studies need to confirm factors with the potential to increase adherence to long-term aspirin. PMID:23831164

  13. Research on wear properties of centrifugal dredge pump based on liquid-solid two-phase fluid simulations

    Science.gov (United States)

    Peng, G. J.; Luo, Y. Y.; Wang, Z. W.

    2015-01-01

    The impeller and casing of dredge pump are worn by sediment in the flow. However, there are few studies about abrasion of the impeller and casing for normal pump operating conditions. This paper investigated the relationship between the wear rates on the surfaces of the impeller as well as casing and the sediment concentration, with the distribution of the wear rates for normal pump operating condition analyzed. An Eulerian-Lagrangian Computational Fluid Dynamics (CFD) procedure was used to simulate steady liquid-solid two-phase flow for various operating conditions. The Finnie model was then used to predict the abrasion. The results show that, the wear rate relative value of impeller and casing surface increase as the sediment concentration increases. The wear rate relative value of impeller and casing surface is larger when the pump is in low flow rate condition, and the value of casing surface is larger than that of the impeller. The wear rate relative value of pump is low when pump is in high efficiency condition. This paper shows the abrasion characteristics on the impeller and casing with sediment flow and provides reference data for predicting the abrasion conditions in the flow passage components for a dredge pump.

  14. Scavenged body heat powered infusion pump

    International Nuclear Information System (INIS)

    An infusion pump powered by body heat is investigated in this paper, with the goal of addressing the needs of dermal wound healing. The infusion pump incorporates a Knudsen gas pump, a type of thermally driven pump, to pneumatic push the pharmaceutical agent from a reservoir. Two designs are considered: an integrated pump and reservoir, and a design with cascaded pump and reservoir. Thermal models are developed for both pumps, and the simulations agree well with the experimental results. The integrated pump and reservoir design uses hydrophobic materials to prevent a flow from occurring unless the infusion pump is placed on a human body. Flow rates in the µL min−1 range for the integrated pump and reservoir, and approximately 70 µL min−1 for the cascaded pump were obtained. The dynamic behavior of the cascaded pump is described based on the thermal models. Multiple copies of the cascaded pump are easily made in series or parallel, to increase either the pressure or the flow rate. The flow rate of multiple pumps in series does not change, and the pressure of multiple pumps in parallel does not change. (paper)

  15. Design and testing of micro fluidic chemical analysis chip integrated with micro valveless pump

    Institute of Scientific and Technical Information of China (English)

    FU; Xin; XIE; Haibo; YANG; Huayong; JIA; Zhijian; FANG; Qun

    2005-01-01

    A new structure and working principle of the chip integrated with micro valveless pump for capillary electrophoresis was proposed in this paper. The micro valveless pump with plane structure has advantages of simple structure, and the process technology is compatible with existing micro chips for capillary electrophoresis. Based upon the mathematical model, simulation study of micro pump was carried out to investigate the influence of structural parameters on flow characteristics, and the performance of the integrated micro pump was also tested with different control parameters. The simulation results agree with the experimental results. Three samples, which are amino acid, fluorescein and buffer solution, have been examined with this chip. The results of the primary experiments showed that the micro valveless pump was promising in the integration and automatization of miniature integrated fluidic systems.

  16. A review of instruments to measure interprofessional team-based primary care.

    Science.gov (United States)

    Shoemaker, Sarah J; Parchman, Michael L; Fuda, Kathleen Kerwin; Schaefer, Judith; Levin, Jessica; Hunt, Meaghan; Ricciardi, Richard

    2016-07-01

    Interprofessional team-based care is increasingly regarded as an important feature of delivery systems redesigned to provide more efficient and higher quality care, including primary care. Measurement of the functioning of such teams might enable improvement of team effectiveness and could facilitate research on team-based primary care. Our aims were to develop a conceptual framework of high-functioning primary care teams to identify and review instruments that measure the constructs identified in the framework, and to create a searchable, web-based atlas of such instruments (available at: http://primarycaremeasures.ahrq.gov/team-based-care/ ). Our conceptual framework was developed from existing frameworks, the teamwork literature, and expert input. The framework is based on an Input-Mediator-Output model and includes 12 constructs to which we mapped both instruments as a whole, and individual instrument items. Instruments were also reviewed for relevance to measuring team-based care, and characterized. Instruments were identified from peer-reviewed and grey literature, measure databases, and expert input. From nearly 200 instruments initially identified, we found 48 to be relevant to measuring team-based primary care. The majority of instruments were surveys (n = 44), and the remainder (n = 4) were observational checklists. Most instruments had been developed/tested in healthcare settings (n = 30) and addressed multiple constructs, most commonly communication (n = 42), heedful interrelating (n = 42), respectful interactions (n = 40), and shared explicit goals (n = 37). The majority of instruments had some reliability testing (n = 39) and over half included validity testing (n = 29). Currently available instruments offer promise to researchers and practitioners to assess teams' performance, but additional work is needed to adapt these instruments for primary care settings. PMID:27212003

  17. Whole blood pumping with a microthrottle pump

    OpenAIRE

    Davies, M J; Johnston, I. D.; Tan, C. K. L.; Tracey, M. C.

    2010-01-01

    We have previously reported that microthrottle pumps (MTPs) display the capacity to pump solid phase suspensions such as polystyrene beads which prove challenging to most microfluidic pumps. In this paper we report employing a linear microthrottle pump (LMTP) to pump whole, undiluted, anticoagulated, human venous blood at 200 μl min−1 with minimal erythrocyte lysis and no observed pump blockage. LMTPs are particularly well suited to particle suspension transport by virtue of their relatively ...

  18. Medical Assistant-based care management for high risk patients in small primary care practices

    DEFF Research Database (Denmark)

    Freund, Tobias; Peters-Klimm, Frank; Boyd, Cynthia M.;

    2016-01-01

    Background: Patients with multiple chronic conditions are at high risk of potentially avoidable hospital admissions, which may be reduced by care coordination and self-management support. Medical assistants are an increasingly available resource for patient care in primary care practices. Objective......: To determine whether protocol-based care management delivered by medical assistants improves patient care in patients at high risk of future hospitalization in primary care. Design: Two-year cluster randomized clinical trial. Setting: 115 primary care practices in Germany. Patients: 2,076 patients...... with type 2 diabetes, chronic obstructive pulmonary disease, or chronic heart failure and a likelihood of hospitalization in the upper quartile of the population, as predicted by insurance data analysis. Intervention: We compared protocol-based care management including structured assessment, action...

  19. Flow Analysis of the Cleveland Clinic Centrifugal Pump

    Science.gov (United States)

    Veres, Joseph P.; Golding, Leonard A. R.; Smith, William A.; Horvath, David; Medvedev, Alexander

    1997-01-01

    An implantable ventricular assist rotordynamic blood pump is being developed by the Cleveland Clinic Foundation in cooperation with the NASA Lewis Research Center. At the nominal design condition, the pump provides blood flow at the rate of 5 liters per minute at a pressure rise of 100 mm of mercury and a rotative speed of 3000 RPM. Bench testing of the centrifugal pump in a water/glycerin mixture has provided flow and pressure data at several rotative speeds. A one-dimensional empirical based pump flow analysis computer code developed at NASA Lewis Research Center has been used in the design process to simulate the flow in the primary centrifugal pump stage. The computer model was used to size key impeller and volute geometric parameters that influence pressure rise and flow. Input requirements to the computer model include a simple representation of the pump geometry. The model estimates the flow conditions at the design and at off-design operating conditions at the impeller leading and trailing edges and the volute inlet and exit. The output from the computer model is compared to flow and pressure data obtained from bench testing.

  20. Evaluation of satellite based indices for primary production estimates in a sparse savanna in the Sudan

    Directory of Open Access Journals (Sweden)

    M. Sjöström

    2008-07-01

    Full Text Available One of the more frequently applied methods for integrating controls on primary production through satellite data is the Light Use Efficiency (LUE approach. Satellite indices such as the Enhanced Vegetation Index (EVI and the Shortwave Infrared Water Stress Index (SIWSI have previously shown promise as predictors of primary production in several different environments. In this study, we evaluate EVI and SIWSI derived from the Moderate Resolution Imaging Spectroradiometer (MODIS satellite sensor against in-situ measurements from central Sudan in order to asses their applicability in LUE-based primary production modelling within a water limited environment. Results show a strong correlation between EVI against gross primary production (GPP, demonstrating the significance of EVI for deriving information on primary production with relatively high accuracy at similar areas. Evaluation of SIWSI however, reveal that the fraction of vegetation apparently is to low for the index to provide accurate information on canopy water content, indicating that the use of SIWSI as a predictor of water stress in satellite data-driven primary production modelling in similar semi-arid ecosystems is limited.

  1. Using a Breast Pump

    Science.gov (United States)

    ... you can relax and not be disturbed while pumping. If you have an electric pump, find an ... otherwise irritating your nipple or breast tissue. Begin Pumping If your pump is electric or battery-powered, ...

  2. 基于溶血性能的离心式旋转血泵设计%Design of Centrifugal Blood Pump Based on Hemolysis Estimation

    Institute of Scientific and Technical Information of China (English)

    阮晓东; 陈松松; 钱伟; 邹俊; 付新

    2011-01-01

    Hemolytic performance is an important index of blood pump. Based on average shear stress model,we optimized the parameters of the impeller to reduce the time of red blood cells flowing through the impeller and the average shear stress they suffered in the process. Computational fluid dynamic simulations of the flow in the centrifugal blood pump were used in the present study. The traces and flow parameters of red cells in the blood pump were acquired. With the help of empirical formulas of hemolysis, hemolytic performances of pump in different flow rates were acquired. The predicted blood damage index was between 0. 006 and 0. 015, which showed that hemolysis performance of the blood pump is satisfactory. In conclusion the design method for blood pump is applicable.%溶血性能是衡量血泵性能的一个重要指标.基于平均剪切应力模型,通过减少红细胞流经叶轮的时间和降低它在此过程中所受平均剪切应力的方法,对离心血泵进行设计,进而改善溶血性能.采用商用流体仿真软件Fluent,对血泵内的三维不可压湍流流场进行数值模拟,得到红细胞在血泵内的流动迹线和流动参数;应用溶血估算公式,分析不同流量下血泵的溶血性能,计算得到溶血估算值在0.006-0.015之间,有较好的溶血性能,满足血泵对溶血性能的要求.

  3. Inquiry-Based Science Education: Towards a Pedagogical Framework for Primary School Teachers

    Science.gov (United States)

    van Uum, Martina S. J.; Verhoeff, Roald P.; Peeters, Marieke

    2016-01-01

    Inquiry-based science education (IBSE) has been promoted as an inspiring way of learning science by engaging pupils in designing and conducting their own scientific investigations. For primary school teachers, the open nature of IBSE poses challenges as they often lack experience in supporting their pupils during the different phases of an open…

  4. Antibiotic prescribing patterns in out-of-hours primary care: A population-based descriptive study

    NARCIS (Netherlands)

    Huibers, L.; Moth, G.; Christensen, M.B.; Vedsted, P.

    2014-01-01

    Abstract Objective. To describe the frequency and characteristics of antibiotic prescribing for different types of contacts with the Danish out-of-hours (OOH) primary care service. Design. Population-based observational registry study using routine registry data from the OOH registration system on p

  5. Evaluation of the structure and provision of primary care in Slovakia: a survey-based project.

    NARCIS (Netherlands)

    Boerma, W.G.W.; Wiegers, T.A.; Baltag, V.

    2012-01-01

    Health reforms are part of the profound and comprehensive changes in essential societal functions and values occurring in many eastern European countries in economic and political transition. Primary care reform is not always evidence based and may be driven by political arguments or the interests o

  6. Hypersensitivity following Retreatment with Carboplatin a Decade after Completion of Primary Platinum-Based Chemotherapy

    OpenAIRE

    Williams, Laura; Markman, Maurie

    2009-01-01

    The relatively rapid development of a platinum-associated hypersensitivity reaction in an ovarian cancer patient receiving second-line chemotherapy more than a decade following her last course of primary platinum-based chemotherapy demonstrates that the prolonged persistence of immune cells recognizing platinum after sensitization has been established.

  7. Inquiry-based science education : towards a pedagogical framework for primary school teachers

    NARCIS (Netherlands)

    van Uum, Martina S J; Verhoeff, Roald P.; Peeters, Marieke

    2016-01-01

    Inquiry-based science education (IBSE) has been promoted as an inspiring way of learning science by engaging pupils in designing and conducting their own scientific investigations. For primary school teachers, the open nature of IBSE poses challenges as they often lack experience in supporting their

  8. Treating Opioid Addiction With Buprenorphine-Naloxone in Community-Based Primary Care Settings

    OpenAIRE

    Mintzer, Ira L.; Eisenberg, Mark; Terra, Maria; MacVane, Casey; Himmelstein, David U.; Woolhandler, Steffie

    2007-01-01

    PURPOSE Office-based treatment of opioid addiction with a combination of buprenorphine and naloxone was approved in 2002. Efficacy of this treatment in nonresearch clinical settings has not been studied. We examined the efficacy and practicality of buprenorphine-naloxone treatment in primary care settings.

  9. Evaluation of structure and provision of primary care in Romania: a survey-based project.

    NARCIS (Netherlands)

    Boerma, W.G.W.; Wiegers, T.A.; Baltag, V.; Teunissen, E.; Farcasanu, D.

    2012-01-01

    In many countries in transition, health reforms are part of profound and comprehensive changes in essential societal functions and values. Reforms of (primary) care are not always based on evidence, and progress may be driven by political arguments or the interests of specific professional groups, r

  10. Method for Lumped Parameter simulation of Digital Displacement pumps/motors based on CFD

    DEFF Research Database (Denmark)

    Rømer, Daniel; Johansen, Per; Pedersen, Henrik C.;

    2013-01-01

    design and control of digital displacement machines, there is a need for simulation models, preferably models with low computational cost. Therefore, a low computational cost generic lumped parameter model of digital displacement machine is presented, including a method for determining the needed model...... parameters based on steady CFD results, in order to take detailed geometry information into account. The response of the lumped parameter model is compared to a computational expensive transient CFD model for an example geometry....

  11. Reactor coolant pump flywheel

    Science.gov (United States)

    Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

    2013-11-26

    A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

  12. Conception, Design and Materialisation of a pumping-based extrusion system for food 3D-printing

    OpenAIRE

    Belohlav, Vojtech

    2015-01-01

    The aim of this master thesis is to provide the design of the system for the food printing that would eliminate the disadvantages of previous end effectors variants. Within the conceptual design and study of alternatives, an overview of existing methods of pumping has been elaborated. The main objective of this section is to provide an overview of the techniques and equipment used for pumping materials in the food industry, where it is important to observe health and safety regulations and su...

  13. Peristaltic pumps work in nano scales

    OpenAIRE

    Farahpour, Farnoush; Ejtehadi, Mohammad Reza

    2013-01-01

    A design for a pump is suggested which is based on well-known peristaltic pumps. In order to simply describe the operation of the proposed pump, an innovative interpretation of low Reynolds number swimmers is presented and thereafter a similar theoretical model would be suggested to quantify the behavior of the pumps. A coarse-grained molecular dynamic simulation is used to examine the theoretical predictions and measure the efficiency of the pump in nano scales. It is shown that this pump wi...

  14. Absorption heat pumps

    Science.gov (United States)

    Huhtinen, M.; Heikkilae, M.; Andersson, R.

    1987-03-01

    The aim of the study was to analyze the technical and economic feasibility of absorption heat pumps in Finland. The work was done as a case study: the technical and economic analyses have been carried out for six different cases, where in each the suitable size and type of the heat pump plant and the auxiliary components and connections were specified. The study also detailed the costs concerning the procurement, installation and test runs of the machinery, as well as the savings in energy costs incurred by the introduction of the plant. Conclusions were drawn of the economic viability of the applications studied. The following cases were analyzed: heat recovery from flue gases and productin of district heat in plants using peat, natural gas, and municipal wastes as a fuel. Heat recovery in the pulp and paper industry for the upgrading of pressure of secondary steam and for the heating of white liquor and combustion and drying the air. Heat recovery in a peat-fulled heat and power plant from flue gases that have been used for the drying of peat. According to the study, the absorption heat pump suits best to the production of district heat, when the heat source is the primary energy is steam produced by the boiler. Included in the flue as condensing is the purification of flue gases. Accordingly, benefit is gained on two levels in thick applications. In heat and power plants the use of absorption heat pumps is less economical, due to the fact that the steam used by the pump reduces the production of electricity, which is rated clearly higher than heat.

  15. Thermoelectric electromagnetic pump design for SP-100

    International Nuclear Information System (INIS)

    This paper describes the design of the Thermoelectric Electromagnetic (TEM) pump used in the SP-100 space power system. The TEM pump is designed to pump liquid (molten) lithium (Li) coolant in the Primary Heat Transport Subsystem (PHTS) and Heat Rejection Subsystem (HRSS). The pump utilizes advanced Thermoelectric (TE) cells to generate electric current that induces magnetic flux in a Z-shaped magnetic structure. The electric current and magnetic flux pass through the liquid Li perpendicular to each other to create the pumping force. The TE cells are semiconductors located between rectangular ducts connected to the reactor hot PHTS piping and the cooler HRSS piping. The temperature difference (ΔT) across the TE cells generates the voltage to power the pump. The design provides a minimum mass, self-regulated pump, with no moving parts and self-powered by an internal temperature gradient

  16. Spin exchange optical pumping based polarized {sup 3}He filling station for the Hybrid Spectrometer at the Spallation Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, C. Y.; Tong, X.; Brown, D. R.; Culbertson, H.; Kadron, B.; Robertson, J. L. [Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Graves-Brook, M. K. [Research Accelerator Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Hagen, M. E. [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Lee, W. T. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234 (Australia); Winn, B. [Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2013-06-15

    The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60 Degree-Sign horizontal and 15 Degree-Sign vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized {sup 3}He filling station based on the spin exchange optical pumping method. It is designed to supply polarized {sup 3}He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the {sup 3}He pressure with respect to the scattered neutron energies. The depolarized {sup 3}He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

  17. Photoacoustic imaging of a near-infrared fluorescent marker based on dual wavelength pump-probe excitation

    Science.gov (United States)

    Märk, Julia; Theiss, Christoph; Schmitt, Franz-Josef; Laufer, Jan

    2014-03-01

    Photoacoustic imaging has been used to determine the spatial distribution of fluorophores, such as exogenous dyes and genetically expressed proteins, from images acquired in phantoms and in vivo. Most methods involve the acquisition of multiwavelength images and rely on differences in the absorption spectra of the tissue chromophores to estimate the spatial distribution and abundance of the latter using spectral decomposition techniques, such as model based inversion schemes. However, the inversion of 3-D images can be computationally expensive. Experimental approaches to localising contrast agents may therefore be useful, especially if quantification is not essential. This work aims to develop a method for determining the spatial distribution of a near-infrared fluorescent cell marker from images acquired using dual wavelength excitation. The excitation wavelengths coincided with the absorption and emission spectrum of the fluorophore. The contrast mechanism relies on reducing the excited state lifetime of the fluorophore by inducing stimulated emission. This changes the amount of energy thermalized by the fluorophore, and hence the photoacoustic signal amplitude. Since this is not observed in endogenous chromophores, the background may be removed by subtracting two images acquired with and without pulse delay between the pump and probe pulses. To characterise the fluorophore, the signal amplitude is measured in a cuvette as a function of pulse delay, concentration, and fluence. The spatial distribution of the fluorophore is determined from images acquired in realistic tissue phantoms. This method may be suitable for in vivo applications, such as imaging of exogenous or genetically expressed fluorescent cell markers.

  18. Primary Health Care Software-A Computer Based Data Management System

    Directory of Open Access Journals (Sweden)

    Tuli K

    1990-01-01

    Full Text Available Realising the duplication and time consumption in the usual manual system of data collection necessitated experimentation with computer based management system for primary health care in the primary health centers. The details of the population as available in the existing manual system were used for computerizing the data. Software was designed for data entry and analysis. It was written in Dbase III plus language. It was so designed that a person with no knowledge about computer could use it, A cost analysis was done and the computer system was found more cost effective than the usual manual system.

  19. Diode-pumped two-frequency lasers based on c-cut vanadate crystals

    International Nuclear Information System (INIS)

    The luminescent and lasing properties of the neo-dymium ion at the 4F3/2-4I11/2 transition in c-cut vanadate crystals (Nd:YVO4, Nd:GdVO4, and Nd:Gd1-xYxVO4) are studied. Tuning of the laser radiation wavelength (Δλ = 5.4 nm) is demonstrated. Two-frequency laser schemes with the use of a Lyot filter, a Fabry-Perot etalon, and a Brewster prism as spectral selection elements are proposed and experimentally realised. Stable two-frequency lasing of a laser based on the c-cut Nd:GdVO4 crystal was obtained in the cw, Q-switched (nanosecond pulses), and active acousto-optic mode-locked (picosecond pulses) regimes. (lasers)

  20. Developing the Botswana Primary Care Guideline: an integrated, symptom-based primary care guideline for the adult patient in a resource-limited setting

    OpenAIRE

    Tsima,; Setlhare, Vincent; Nkomazana, Oathokwa

    2016-01-01

    Billy M Tsima,1 Vincent Setlhare,1 Oathokwa Nkomazana2 1Department of Family Medicine and Public Health, 2Department of Surgery, Faculty of Medicine, University of Botswana, Gaborone, Botswana Background: Botswana’s health care system is based on a primary care model. Various national guidelines exist for specific diseases. However, most of the guidelines address management at a tertiary level and often appear nonapplicable for the limited resources in primary care facilities. An in...

  1. Development of a Compact Efficient Cooling Pump for Space Suit Life Support Systems

    Science.gov (United States)

    vanBoeyen, Roger W.; Reeh, Jonathan A.; Trevino, Luis

    2008-01-01

    With the increasing demands placed on extravehicular activity (EVA) for the International Space Station (ISS) assembly and maintenance, along with planned lunar and Martian missions, the need for increased human productivity and capability becomes ever more critical. This is most readily achieved by reduction in space suit weight and volume, and increased hardware reliability, durability, and operating lifetime. Considerable progress has been made with each successive generation of space suit design; from the Apollo A7L suit, to the current Shuttle Extravehicular Mobile Unit (EMU) suit, and the next generation Constellation Space Suit Element (CSSE). However, one area of space suit design which has continued to lag is the fluid pump used to drive the water cooling loop of the Primary Life Support System (PLSS). The two main types of fluid pumps typically used in space applications are rotodynamic pumps (pumping is achieved through a rotary vaned impeller) and displacement pumps (which includes rotary and diaphragm pumps). The rotating and moving parts found in the pumps and electric motor add significantly to the susceptibility to wear and friction, thermal mismatch, and complexity of the pumps. Electric motor-driven pumps capable of achieving high operational reliability are necessarily large, heavy, and energy inefficient. This report describes a development effort conducted for NASA by Lynntech, Inc., who recently demonstrated the feasibility of an electrochemically-driven fluid cooling pump. With no electric motor and minimal lightweight components, an electrochemically-driven pump is expected to be significantly smaller, lighter and achieve a longer life time than conventional rotodynamic and displacement pumps. By employing sulfonated polystyrene-based proton exchange membranes, rather than conventional Nafion membranes, a significant reduction in the actuator power consumption was demonstrated. It was also demonstrated that these membranes possess the

  2. Pump cavitation and inducer design

    International Nuclear Information System (INIS)

    Details of past work on sodium pump development and cavitation studies executed mainly for SNR 300 were reported earlier. Among the requirements for large sodium pumps are long life (200000 hours up to 300000 hours) and small size of impeller and pump, fully meeting the process and design criteria. These criteria are the required 'Q, H, r characteristics' in combination with a low NPSH value and the avoidance of cavitation damage to the pump. The pump designer has to develop a sound hydraulic combination consisting of suction arrangement, impeller design and diffuser. On the other hand the designer is free to choose an optimal pump speed. The pump speed in its turn influences the rotor dynamic pump design and the pump drive. The introduction of the inducer as an integral part of the pump design is based on following advantages: no tip cavitation; (possible) cavitation bubbles move to the open centre due to centrifugal forces on the fluid; the head of the inducer improves the inlet conditions of the impeller. The aim of an inducer is the increase in the suction specific speed (SA value) of a pump whereby the inducer functions as a pressure source improving the impeller inlet conditions. With inducer-impeller combinations values up to SA=15000 are realistic. With the use of an inducer the overall pump sizes can be reduced with Ca. 30%. Pumps commonly available have SA values up to a maximum of ca. 10000. A development programme was executed for SNR 300 in order to reach an increase of the suction specific speed of the impeller from SA 8200 to SA 11000. Further studies to optimize pumps design for the follow up line introduced the 'inducer acting as a pre-impeller' development. This programme was executed in the period 1979-1981. At the FDO premises a scale 1 2.8 inducer impeller combination with a suction specific speed SA=15000 was developed, constructed and tested at the water test rig. This water test rig is equipped with a perspex pipe allowing also visualisation

  3. Developing the Botswana Primary Care Guideline: an integrated, symptom-based primary care guideline for the adult patient in a resource-limited setting

    Directory of Open Access Journals (Sweden)

    Tsima BM

    2016-08-01

    Full Text Available Billy M Tsima,1 Vincent Setlhare,1 Oathokwa Nkomazana2 1Department of Family Medicine and Public Health, 2Department of Surgery, Faculty of Medicine, University of Botswana, Gaborone, Botswana Background: Botswana’s health care system is based on a primary care model. Various national guidelines exist for specific diseases. However, most of the guidelines address management at a tertiary level and often appear nonapplicable for the limited resources in primary care facilities. An integrated symptom-based guideline was developed so as to translate the Botswana national guidelines to those applicable in primary care. The Botswana Primary Care Guideline (BPCG integrates the care of communicable diseases, including HIV/AIDS and noncommunicable diseases, by frontline primary health care workers.Methods: The Department of Family Medicine, Faculty of Medicine, University of Botswana, together with guideline developers from the Knowledge Translation Unit (University of Cape Town collaborated with the Ministry of Health to develop the guideline. Stakeholder groups were set up to review specific content of the guideline to ensure compliance with Botswana government policy and the essential drug list.Results: Participants included clinicians, academics, patient advocacy groups, and policymakers from different disciplines, both private and public. Drug-related issues were identified as necessary for implementing recommendations of the guideline. There was consensus by working groups for updating the essential drug list for primary care and expansion of prescribing rights of trained nurse prescribers in primary care within their scope of practice. An integrated guideline incorporating common symptoms of diseases seen in the Botswana primary care setting was developed.Conclusion: The development of the BPCG took a broad consultative approach with buy in from relevant stakeholders. It is anticipated that implementation of the BPCG will translate into better

  4. Double-shell tank emergency pumping guide

    International Nuclear Information System (INIS)

    This Double-Shell Tank Emergency Pumping Guide provides the preplanning necessary to expeditiously remove any waste that may leak from the primary tank to the secondary tank for Hanfords 28 DSTs. The strategy is described, applicable emergency procedures are referenced, and transfer routes and pumping equipment for each tank are identified

  5. 基于复合热源的热泵型空调器%Heat pump air conditioner based on multiple heat sources

    Institute of Scientific and Technical Information of China (English)

    吴国珊; 凌勋

    2012-01-01

    It is proposed that the air-water multiple heat sources could be the heat source of heat pump air conditioner. Based on the current study condition, the heat pump air conditioner which has a air/family waste water multiple heat source is preliminary designed. The working cycle and characteristics of the air conditioner are analyzed by using the thermodynamic principle. The results show that the refrigeration performance of the heat pump air conditioner is better than that of air source heat pump air conditioner, the heating performance and the situation which the outdoor heat exchanger frosts are improved.%提出将空气-水作为热泵型空调器的复合热源.根据当前的研究状况,初步设计空气-水复合热源热泵型空调器,利用热力学原理分析该空调器的工作循环和特点,结果表明该空调器的制冷性能高于空气源热泵空调器,制热和室外换热器结霜状况得到一定改善.

  6. Scaleable multi-format QCW pump stacks based on 200W laser diode bars and mini bars at 808nm and 940nm

    Science.gov (United States)

    Berk, Yuri; Karni, Yoram; Klumel, Genady; Openhaim, Yaakov; Cohen, Shalom; Yanson, Dan

    2011-03-01

    Advanced solid state laser architectures place increasingly demanding requirements on high-brightness, low-cost QCW laser diode pump sources, with custom apertures both for side and end rod pumping configurations. To meet this need, a new series of scaleable pump sources at 808nm and 940nm was developed. The stacks, available in multiple output formats, allow for custom aperture filling by varying both the length and quantity of stacked laser bars. For these products, we developed next-generation laser bars based on improved epitaxial wafer designs delivering power densities of 20W/mm of emission aperture. With >200W of peak QCW power available from a full-length 1cm bar, we have demonstrated power scaling to over 2kW in 10-bar stacks with 55% wall plug efficiency. We also present the design and performance of several stack configurations using full-length and reduced-length (mini) bars that demonstrate the versatility of both the bar and packaging designs. We illustrate how the ROBUST HEAD packaging technology developed at SCD is capable of accommodating variable bar length, pitch and quantity for custom rod pumping geometries. The excellent all-around performance of the stacks is supported by reliability data in line with the previously reported 20 Gshot space-grade qualification of SCD's stacks.

  7. Hydraulic performance numerical simulation of high specific speed mixed-flow pump based on quasi three-dimensional hydraulic design method

    Science.gov (United States)

    Zhang, Y. X.; Su, M.; Hou, H. C.; Song, P. F.

    2013-12-01

    This research adopts the quasi three-dimensional hydraulic design method for the impeller of high specific speed mixed-flow pump to achieve the purpose of verifying the hydraulic design method and improving hydraulic performance. Based on the two families of stream surface theory, the direct problem is completed when the meridional flow field of impeller is obtained by employing iterative calculation to settle the continuity and momentum equation of fluid. The inverse problem is completed by using the meridional flow field calculated in the direct problem. After several iterations of the direct and inverse problem, the shape of impeller and flow field information can be obtained finally when the result of iteration satisfies the convergent criteria. Subsequently the internal flow field of the designed pump are simulated by using RANS equations with RNG k-ε two-equation turbulence model. The static pressure and streamline distributions at the symmetrical cross-section, the vector velocity distribution around blades and the reflux phenomenon are analyzed. The numerical results show that the quasi three-dimensional hydraulic design method for high specific speed mixed-flow pump improves the hydraulic performance and reveal main characteristics of the internal flow of mixed-flow pump as well as provide basis for judging the rationality of the hydraulic design, improvement and optimization of hydraulic model.

  8. On the development of an innovative gas-fired heating appliance based on a zeolite-water adsorption heat pump; system description and seasonal gas utilization efficiency

    International Nuclear Information System (INIS)

    The main objective of this work is to introduce an innovative hybrid heating appliance incorporating a gas condensing boiler and a zeolite-water adsorption heat pump. The condensing boiler is applied to drive the zeolite-water heat pump for the heating base-load and to assist the heat pump in the so called “mixed operation” mode, in which both the heat pump and the condensing boiler are working in series to cover medium heating demands. Peak heating demands are covered by the condensing boiler in the so called “direct heating” mode. The three operation modes of the hybrid heating appliance have been technically described. In addition, the laboratory test conditions for estimating the seasonal heating performance according to the German Guideline VDI 4650-2 have been introduced. For both heating systems 35/28 °C and 55/45 °C, which represent the typical operating conditions of floor and high temperature radiating heating systems in Europe, seasonal heating gas utilization efficiencies of 1.34 and 1.26 have been measured, respectively with a ground heat source. In two field test installations in one-family houses in Germany, the introduced heating appliance showed 27% more seasonal gas utilization efficiency for heating and domestic hot water production, which is equivalent to a CO2-emission reduction of 20% compared to the gas condensing boiler technology

  9. Hydraulic performance numerical simulation of high specific speed mixed-flow pump based on quasi three-dimensional hydraulic design method

    International Nuclear Information System (INIS)

    This research adopts the quasi three-dimensional hydraulic design method for the impeller of high specific speed mixed-flow pump to achieve the purpose of verifying the hydraulic design method and improving hydraulic performance. Based on the two families of stream surface theory, the direct problem is completed when the meridional flow field of impeller is obtained by employing iterative calculation to settle the continuity and momentum equation of fluid. The inverse problem is completed by using the meridional flow field calculated in the direct problem. After several iterations of the direct and inverse problem, the shape of impeller and flow field information can be obtained finally when the result of iteration satisfies the convergent criteria. Subsequently the internal flow field of the designed pump are simulated by using RANS equations with RNG k-ε two-equation turbulence model. The static pressure and streamline distributions at the symmetrical cross-section, the vector velocity distribution around blades and the reflux phenomenon are analyzed. The numerical results show that the quasi three-dimensional hydraulic design method for high specific speed mixed-flow pump improves the hydraulic performance and reveal main characteristics of the internal flow of mixed-flow pump as well as provide basis for judging the rationality of the hydraulic design, improvement and optimization of hydraulic model

  10. Condition-based maintenance. With application on a heat exchanger and a pump; Tillstaandsbaserat underhaall. Med applikation paa en vaermevaexlare och en pump

    Energy Technology Data Exchange (ETDEWEB)

    Raaberg, Martin; Slaetteke, Ola

    2012-02-15

    Regular maintenance is required to extend the life of a plant's components and maintain optimum operation. Unnecessary outages from maintenance may inflict large monetary losses. Therefore, a cost-effective maintenance system should be condition-based rather than time-based. The optimal maintenance scheme requires a process model and a forecast of the operation conditions of this model. At least one of the model parameters should be affected by the maintenance. To determine the actual status of the plant, the model parameters should be estimated. This requires an analysis of available data to detect degradation of the critical components performance. Base load plants usually operate at maximum production or as close to maximum as possible at stabile conditions during long periods. Since the operating time is long and usually at high load in base load plants, advanced control systems and maintenance planning is most profitable in such plants. Advanced control and process optimization requires dynamic process models. Due to the long operating time of a base load plant, it is natural that its process characteristics change, such as wear and fouling. This means that models must be adapted continuously in order to generate a good approximation and thus a good basis for control and optimization. The problem is that the stable operation condition of a base load plant prevents a good estimate of model parameters through the lack of excitation of the process

  11. A radiation dose study based on analysis of primary color chrominance

    Institute of Scientific and Technical Information of China (English)

    HUANG Jianyue; LI Jianghong; LI Jianwei; JIN Jian

    2015-01-01

    PURPOSE: The purpose of this study was to assess the possibility of measuring radiation dose based on primary color chrominance in chemical solutions. METHODS: We used an aqueous solution with different concentrations of Alphaurine A and Tracid Brilliant Red B. This was irradiated by 1.5-13.5kGy 60Co γ radiation. Data were collected by an instrument that can detect information on the three primary colors. Data were analyzed and manipulated for each experiment. RESULTS AND CONCLUSIONS: The result shows that three primary colors chrominance in the aqueous solutions change with different doses of 60Co γ-rays and different concentrations of Alphaurine A and Tracid Brilliant Red B. For Alphaurine A, the red chrominance is gradually reduced as a function of radiation dose. The blue chrominance gradually increases concurrently. The red and green chrominance changes obviously and inversely, but the green chrominance changes little. In Tracid Brilliant Red B solution, the red chrominance and green chrominance gradually decreases as the radiation dose increases. And the changes are obvious and inverted. The blue chrominance changed little. Our experiments demonstrate that radiation dose can be studied based on three primary colors chrominance. This may be a new tool to measure radiation dose.

  12. Plant proton pumps as markers of biostimulant action

    OpenAIRE

    Daniel Basílio Zandonadi; Mirella Pupo Santos; Lisanne Santos Caixeta; Eduardo Barros Marinho; Lázaro Eustáquio Pereira Peres; Arnoldo Rocha Façanha

    2016-01-01

    ABSTRACT A standard protocol to evaluate the effects of biostimulants on plant physiology is still lacking. The proton pumps present in the vacuolar and plasma membranes are the primary agents responsible for the regulation of the electrochemical gradient that energizes the nutrient uptake system and acid growth mechanism of plant cells. In this study, two of these enzymes were characterized as biochemical markers of biostimulant activity. A simple and fast protocol based on the degree of roo...

  13. Non-adiabatic topological spin pumping

    OpenAIRE

    Deng, W. Y.; Luo, W.; Geng, H; Chen, M. N.; Sheng, L.; Xing, D. Y.

    2016-01-01

    Based on the Floquet scattering theory, we analytically investigate the topological spin pumping for an exactly solvable model. Floquet spin Chern numbers are introduced to characterize the periodically time-dependent system. The topological spin pumping remains robust both in the presence and in the absence of the time-reversal symmetry, as long as the pumping frequency is smaller than the band gap, where the electron transport involves only the Floquet evanescent modes in the pump. For the ...

  14. Rotor-dynamic design aspects for a variable frequency drive based high speed cryogenic centrifugal pump in fusion devices

    International Nuclear Information System (INIS)

    Superconducting magnets of large size are inevitable for fusion devices due to high magnetic field requirements. Forced flow cooling of the superconducting magnets with high mass flowrate of the order ∼3 kg/s is required to keep superconducting magnets within its safe operational boundaries during various plasma scenarios. This important requirement can be efficiently fulfilled by employing high capacity and high efficiency cryogenic centrifugal pumps. The efficiency > 70% will ensure overall lower heat load to the cryoplant. Thermo-hydraulic design of cryogenic centrifugal pump revealed that to achieve the operational regime with high efficiency, the speed should be ∼ 10,000 revolutions per minute. In this regard, the rotor-dynamic design aspect is quite critical from the operational stability point of view. The rotor shaft design of the cryogenic pump is primarily an outcome of optimization between thermal heat-in leak at cryogenic temperature level from ambient, cryogenic fluid impedance and designed rotation speed of the impeller wheel. The paper describes the basic design related to critical speed of the rotor shaft, rotor whirl and system instability prediction to explore the ideal operational range of the pump from the system stability point of view. In the rotor-dynamic analysis, the paper also describes the Campbell plots to ensure that the pump is not disturbed by any of the critical speeds, especially while operating near the nominal and enhanced operating modes. (author)

  15. Multi-objective shape optimization of helico-axial multiphase pump impeller based on NSGA-II and ANN

    International Nuclear Information System (INIS)

    In order to improve the prototype's performance of the helico-axial multiphase pump, a multi-objective optimal method for the pump impeller was developed by combining the artificial neural network (ANN) with non-dominated sorting genetic algorithm-II (NSGA-II). The main geometric parameters influencing the impeller's performance were chosen as the optimization variables, and the sample spaces were structured according to the orthogonal experimental design method. Then the pressure rise and efficiency in specific working conditions were obtained about all the elements in the sample space by numerical simulation. With the simulated results as the input specimen, a multiphase pump performance prediction model was designed through BP neural network. With the obtained prediction model as the fitness value evaluation method, the pump impeller was optimized using the NSGA-II multi-objective genetic algorithm, which finally offered an improved impeller structure with enhanced pressure rise and efficiency. Furthermore, five stages of optimized compression cells were manufactured and applied in experiment test. The result shows compared to the original design, the pressure rise of the optimized pump has increased by ∼10% and the efficiency has increased by ∼3%, which is in keeping with our optimal result and confirms our method is feasible.

  16. [Research on magnetic coupling centrifugal blood pump control based on a self-tuning fuzzy PI algorithm].

    Science.gov (United States)

    Yang, Lei; Yang, Ming; Xu, Zihao; Zhuang, Xiaoqi; Wang, Wei; Zhang, Haibo; Han, Lu; Xu, Liang

    2014-10-01

    The purpose of this paper is to report the research and design of control system of magnetic coupling centrifugal blood pump in our laboratory, and to briefly describe the structure of the magnetic coupling centrifugal blood pump and principles of the body circulation model. The performance of blood pump is not only related to materials and structure, but also depends on the control algorithm. We studied the algorithm about motor current double-loop control for brushless DC motor. In order to make the algorithm adjust parameter change in different situations, we used the self-tuning fuzzy PI control algorithm and gave the details about how to design fuzzy rules. We mainly used Matlab Simulink to simulate the motor control system to test the performance of algorithm, and briefly introduced how to implement these algorithms in hardware system. Finally, by building the platform and conducting experiments, we proved that self-tuning fuzzy PI control algorithm could greatly improve both dynamic and static performance of blood pump and make the motor speed and the blood pump flow stable and adjustable. PMID:25764720

  17. Experimental study of an electromagnetic flow meter for liquid metals based on torque measurement during pumping process

    Science.gov (United States)

    Dubovikova, N.; Kolesnikov, Y.; Karcher, Ch

    2015-11-01

    This paper presents a detailed experimental study on an electromagnetic flow measurement technique to measure the flow rate of liquid metals. The experimental setup consists of a contactless electromagnetic pump with a torque sensor mounted on the pump shaft. The electromagnetic pump is composed of two rotating steel discs having embedded permanent magnets with alternating poles. The rotation of the discs creates a travelling sinusoidal magnetic field and eddy currents within the liquid metal. The metal is contained inside the duct located between the discs of the pump. The interaction of the magnetic field and the induced eddy currents generates an electromagnetic Lorentz force providing the pumping effect. The flow rate is proportional to this force. The torque sensor measures the moment of the discs due to the Lorentz force, which is converted to a flow rate value. We name the method Lorentz torque velocimetry (LTV). The full calibration procedure and experimental investigation of the LTV are described. The method can be used as a non-contact flow rate control technique for liquid metals.

  18. Prevention and primary care research for children. The need for evidence to precede "evidence-based".

    Science.gov (United States)

    Kleinman, L C

    1998-05-01

    Medical care in the United States continues to face tremendous financial pressures. Public and private health policy claim to encourage primary care and preventive services, but also discourage services that have not been demonstrated to be effective and/or cost-effective. This article suggests a model to illustrate the conceptual relationship between traditional American medical care and "evidenced-based" medicine. It further examines how the lack of an adequate research base makes a move to purely evidence-based care premature for primary care and prevention services. The paper defines a new conceptual statistic, the uncertainty index, as the proportion of non-refuted current practice that is also not corroborated by research evidence. The greater the uncertainty index, the less appropriate is a clinical model restricted to evidence-based care. Specific theoretical barriers to outcomes research in prevention are discussed and simple criteria to determine the desirable components of care are suggested. The need for theoretical and empirical research into primary care and prevention, especially for children, is emphasized. Care that is of low risk, not of extremely high cost, and that is generally believed useful by the community of practitioners is particularly desirable in the absence of data refuting its value. PMID:9635081

  19. Reversible heat pump model for seasonal performance optimization

    Energy Technology Data Exchange (ETDEWEB)

    Kinab, Elias; Marchio, Dominique; Riviere, Philippe; Zoughaib, Assaad [MINES ParisTech - Center for Energy and Processes, 60 boulevard Saint Michel, 75006 Paris (France)

    2010-12-15

    Building is one of the economical sectors where solutions are available to significantly reduce energy consumption and greenhouse gases emissions. Electric heat pumps are one of the solutions favored in Europe. Europe recently adopted a conventional primary energy to electricity ratio which enables to compare electric heat pumps and fossil fuel boilers. This leads to an increased consideration for the evaluation of the seasonal performances of heat pumps. Nowadays, the design and sizing of heat pumps are still based on full load performance in order to fulfill thermal comfort under extreme conditions. However, the HVAC industry is switching to designs based on improved seasonal performance. The objective of this work is to model an air to water reversible heat pump that can re-design its components for seasonal performance improvement. In this context, we will present a system model including detailed sub-models of each component of the system: heat exchangers, compressor, and expansion valve. The model converges with the system thermodynamic equilibrium after simulating each component separately. Results obtained are validated through experimental data per component and for the whole cycle. Modeling requirements for the purpose of simulating seasonal performance improvements are discussed. (author)

  20. Output speed and flow of double-acting double-stator multi-pumps and multi-motors

    Institute of Scientific and Technical Information of China (English)

    De-sheng WEN; Zhi-li WANG; Jun GAO; Yong ZHANG; Shi-jun LV; Tetsuhiro TSUKIJI

    2011-01-01

    The primary focus of this study was to investigate a series of novel motors and pumps, based on a new type of structure called double-stator. The double-stator structure can be used as pump or motor just based on the application requirements. A certain amount of pumps or motors can be formed in one shell, and these sub-pumps or sub-motors can work alone or be combined without influence on each other. So this kind of double-stator pump (motor) is called a multi-pump (multi-motor). Through the analysis of multifarious connection modes of the double-acting double-stator multi-pumps and multi-motors, the mathematical expressions of the output flow rate and the rotational speed are acquired. The results indicate that a quantity of different flow rates can be provided by one fixed-displacement multi-pump under the condition of unalterable driven speed by electromotor. Likewise,when supplied by settled input flow, without complex variable mechanism, the functions of double-speed, multiple-speed, and even differential connection can be obtained by employing the use of a double-stator multi-motor. The novel hydraulic transmission is made of such a double-stator multi-pump and multi-motor, and has broad application prospects.

  1. High Performance Space Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — PDT is proposing a High Performance Space Pump based upon an innovative design using several technologies. The design will use a two-stage impeller, high...

  2. Mammalian models of chemically induced primary malignancies exploitable for imaging-based preclinical theragnostic research

    OpenAIRE

    Liu, Yewei; YIN Ting; Feng, Yuanbo; Cona, Marlein Miranda; Huang, Gang; Liu, Jianjun; Song, Shaoli; Jiang, Yansheng; Xia, Qian; Swinnen, Johannes V; Bormans, Guy; Himmelreich, Uwe; Oyen, Raymond; Ni, Yicheng

    2015-01-01

    Compared with transplanted tumor models or genetically engineered cancer models, chemically induced primary malignancies in experimental animals can mimic the clinical cancer progress from the early stage on. Cancer caused by chemical carcinogens generally develops through three phases namely initiation, promotion and progression. Based on different mechanisms, chemical carcinogens can be divided into genotoxic and non-genotoxic ones, or complete and incomplete ones, usually with an organ-spe...

  3. Effects of Laser Peripheral Iridotomy in Subgroups of Primary Angle Closure Based on Iris Insertion

    OpenAIRE

    Sung-Cheol Yun; Ji Wook Hong; Kyung Rim Sung; Jin Young Lee

    2015-01-01

    Purpose. To investigate the effect of laser peripheral iridotomy (LPI) in subgroups of primary angle closure based on iris insertion configuration. Methods. Anterior segment optical coherence tomography (AS-OCT) images were obtained before and two weeks after LPI. Qualitative classification of angle closure eyes according to iris insertion (basal insertion group (BG) and nonbasal insertion group (NBG)) was performed. Anterior chamber depth (ACD), lens vault (LV), iris curvature, iris area, ir...

  4. A new physically-based quantification of marine isoprene and primary organic aerosol emissions

    OpenAIRE

    B. Gantt; N. Meskhidze; D. Kamykowski

    2009-01-01

    The global marine sources of organic carbon (OC) are estimated here using a physically-based parameterization for the emission of marine isoprene and primary organic matter. The marine isoprene emission model incorporates new physical parameters such as light sensitivity of phytoplankton isoprene production and dynamic euphotic depth to simulate hourly marine isoprene emissions totaling 0.92 Tg C yr−1. Sensitivity studies using different schemes for the euphot...

  5. Multimedia Scenario Based Learning Programme for Enhancing the English Language Efficiency among Primary School Students

    OpenAIRE

    Navnath Tupe

    2015-01-01

    This research was undertaken with a view to assess the deficiencies in English language among Primary School Children and to develop Multimedia Scenario Based Learning Programme (MSBLP) for mastery of English language which required special attention and effective treatment. The experimental study with pretest, post-test control group design was employed to carry out the experiment of MSBLP in a sample school and to determine its efficacy for enhancing English Language skill...

  6. The Degradation Interface of Magnesium Based Alloys in Direct Contact with Human Primary Osteoblast Cells

    OpenAIRE

    Ahmad Agha, Nezha; Willumeit-Römer, Regine; Laipple, Daniel; Luthringer, Bérengère; Feyerabend, Frank

    2016-01-01

    Magnesium alloys have been identified as a new generation material of orthopaedic implants. In vitro setups mimicking physiological conditions are promising for material / degradation analysis prior to in vivo studies however the direct influence of cell on the degradation mechanism has never been investigated. For the first time, the direct, active, influence of human primary osteoblasts on magnesium-based materials (pure magnesium, Mg-2Ag and Mg-10Gd alloys) is studied for up to 14 days. Se...

  7. The effects of psychological treatment in primary care in Sweden—A practice-based study

    OpenAIRE

    Holmqvist, Rolf; Ström, Thomas; Foldemo, Anniqa

    2014-01-01

    Background: Practice-based studies have found substantial effects of psychological treatment in routine care, often equivalent between treatment methods. Factors that moderate treatment outcome may be important to assess. Aim: The purpose of this study was to evaluate treatment outcome in psychological treatment in primary care, and to compare outcome between the most frequently used methods. An additional aim was to study factors that might moderate outcome differences. Method: The Clinical ...

  8. Primary four students’ development of reading ability through inquiry-based learning projects

    OpenAIRE

    Fung, HF; Chow, K; Ng, HWR; Loh, EKY; Chu, SKW; Tse, SK

    2008-01-01

    This paper is part of a bigger study that investigates a collaborative instructional approach involving three kinds of teachers (Information Technology, General Studies, and Chinese) and the school librarian in guiding primary 4 (P4) students through two phases of inquiry-based learning (IBL) projects, each lasting for 2-3 months in 2006-2007. This collaborative approach in guiding students through the IBL projects has proven to be effective. Not only did the participating students signifi...

  9. Game-based programming towards developing algorithmic thinking skills in primary education

    OpenAIRE

    Hariklia Tsalapatas; Olivier Heidmann; Rene Alimisi; Elias Houstis

    2012-01-01

    This paper presents cMinds, a learning intervention that deploys game-based visual programming towards building analytical, computational, and critical thinking skills in primary education. The proposed learning method exploits the structured nature of programming, which is inherently logical and transcends cultural barriers, towards inclusive learning that exposes learners to algorithmic thinking. A visual programming environment, entitled ‘cMinds Learning Suite’, has been developed aimed fo...

  10. How primary school teachers posed problems for inquiry based mathematics education

    Czech Academy of Sciences Publication Activity Database

    Hošpesová, A.; Samková, L.; Tichá, Marie; Roubíček, Filip

    Prague: Charles University, Faculty of Education, 2015 - (Novotná, J.; Moraová, H.), s. 156-165 ISBN 978-80-7290-833-2. [SEMT'15 - International Symposium, Elementary Maths Teaching. Praha (CZ), 16.08.2015-21.08.2015] R&D Projects: GA ČR(CZ) GA14-01417S Institutional support: RVO:67985840 Keywords : inquiry based mathematics education * posing problems * primary school teacher training * pre-service and in-service teachers Subject RIV: AM - Education

  11. THE RELATIONSHIP BETWEEN ETHICAL LEADERSHIP AND ORGANIZATIONAL CYNICISM BASED ON PRIMARY TEACHERS` PERCEPTIONS

    OpenAIRE

    Akan, Durdağı; BEKTAŞ, Fatih; YILDIRIM, İsa

    2014-01-01

    This study aims to determine the relationship between the concepts of ethical leadership and organizational cynicism based on primary teachers` perceptions.In line with this objective, developed by Yilmaz (2005) the Ethical Leadership Scale and developed by Sagır and Oguz (2012) the Organizational Cynicism scale were applied on 221 teachers who were working in working his in the school. Pearson`s Moment Correlation Analysis and Multilinear Regression Analysis techniques were utilized in anal...

  12. Translating an Evidence-based Lifestyle Intervention Program into Primary Care: Lessons Learned

    OpenAIRE

    Blonstein, Andrea C.; Yank, Veronica; Stafford, Randall S.; Wilson, Sandra R.; Rosas, Lisa Goldman; Ma, Jun

    2013-01-01

    Obesity is one of the top health priorities in the United States. Primary care physicians are the designated “gatekeepers” for obesity prevention, detection, and treatment. However, they and the current U.S. health care structure and reimbursement systems are often ill-equipped to implement evidence-based obesity care. The Group Lifestyle Balance™ (GLB) program is a group-delivery adaptation of the predominantly one-on-one lifestyle intervention proven efficacious in the Diabetes Prevention P...

  13. Consultations with general practitioners on patient safety measures based on routinely collected data in primary care

    OpenAIRE

    Tsang, C; Majeed, A; Aylin, P

    2012-01-01

    OBJECTIVES To gauge the opinions of doctors working, or interested, in general practice on monitoring patient safety using administrative data. The findings will inform the development of routinely collected data-based patient safety indicators in general practice and elsewhere in primary care. DESIGN Non-systematic participant recruitment, using personal contacts and colleagues' recommendations. SETTING Face-to-face consultations at participants' places of work, between June 2010 a...

  14. Use of Activity Based Joyful Learning Approach in Teaching Environmental Science Subject At Primary Level

    OpenAIRE

    Jadal M.M.

    2012-01-01

    Achievement of interdisciplinary competencies through the teaching of one discipline isa recurring challenge of present-day teaching –learning process. At the primary stage ofour school Education, the subject environmental studies seems to be a suitablecurricular medium, through the teaching of which the competencies of many other areascan be developed. The main focus of present study is to examine the effectiveness ofactivity-based joyful learning approach(ABJL) over traditional method of te...

  15. Efficient, reliable, long-lifetime, diode-pumped Nd:YAG laser for space-based vegetation topographical altimetry.

    Science.gov (United States)

    Coyle, Donald B; Kay, Richard B; Stysley, Paul R; Poulios, Demetrios

    2004-09-20

    A highly efficient, diode-pumped, Nd:YAG laser is described. The oscillator utilizes an unstable resonator design with a Gaussian reflectivity output coupler and a side-pumped zigzag slab gain medium. The laser produces 18-mJ, 10-ns pulses at a repetition rate of 242 Hz in a near-TEM00 mode with an optical efficiency of up to 14%. An extended performance test was recently concluded in which the transmitter operated at reduced output for more than 4.8 x 10(9) shots with no optical damage. Design criteria, beam quality, and lifetime data are presented. PMID:15473245

  16. Mid-infrared supercontinuum generation based on cascaded Raman scattering in a few-mode As2S3 fiber pumped by a thulium-doped fiber laser.

    Science.gov (United States)

    Yao, Jinmei; Zhang, Bin; Yin, Ke; Yang, Linyong; Hou, Jing; Lu, Qisheng

    2016-06-27

    By pumping a 1.7-m-long As2S3 fiber at 2050 nm directly, a fiber-based mid-infrared supercontinuum (SC) source with an output power of 366 mW is demonstrated. This is the first experimental demonstration to obtain such a mid-infrared SC in a piece of chalcogenide fiber pumped at 2 μm directly. The cut-off wavelength of the As2S3 fiber is 3.5 μm, indicating that it could support several modes at around 2 μm. It is found that nonlinear spectral broadening mechanisms in the few-mode chalcogenide fiber could be affected through adjusting the butt-coupling position. That is because different positions will excite different modes that correspondingly possess different nonlinearity and dispersion characteristics. When stimulated Raman scattering (SRS) corresponding to the excitation of the fundamental mode becomes dominant in this few-mode fiber, an efficient cascaded SRS-based SC is obtained with five Stokes peaks ranging from 2 μm to 3.4 μm. Results from numerical simulation are in accord with the experimental results, showing that it is feasible to obtain an SRS based mid-infrared SC in a step-index As2S3 fiber by using a 2 μm high peak power picosecond laser to pump directly. PMID:27410625

  17. Experimental evaluation of radiator control based on primary supply temperature for district heating substations

    International Nuclear Information System (INIS)

    . To maintain a stable indoor temperature at times when the primary supply and outdoor temperatures deviates from their assumed relation, the radiator system flow must be controlled by an additional control-loop. The results confirms that it is possible to control the radiator system based on the primary supply temperature while maintaining comfort; however, conclusions regarding improvements in ΔT were hard to distinguish.

  18. Human Aorta Is a Passive Pump

    Science.gov (United States)

    Pahlevan, Niema; Gharib, Morteza

    2012-11-01

    Impedance pump is a simple valveless pumping mechanism that operates based on the principles of wave propagation and reflection. It has been shown in a zebrafish that a similar mechanism is responsible for the pumping action in the embryonic heart during early stages before valve formation. Recent studies suggest that the cardiovascular system is designed to take advantage of wave propagation and reflection phenomena in the arterial network. Our aim in this study was to examine if the human aorta is a passive pump working like an impedance pump. A hydraulic model with different compliant models of artificial aorta was used for series of in-vitro experiments. The hydraulic model includes a piston pump that generates the waves. Our result indicates that wave propagation and reflection can create pumping mechanism in a compliant aorta. Similar to an impedance pump, the net flow and the flow direction depends on the frequency of the waves, compliance of the aorta, and the piston stroke.

  19. Botulinum Toxin Clinic-Based Epidemiologic Survey of Adults with Primary Dystonia in East China

    Directory of Open Access Journals (Sweden)

    Li Wang

    2012-05-01

    Full Text Available Background and Purpose: Primary focal or segmental dystonia is a rare clinical condition. The clinical features of dystonia have not been evaluated in China. We performed a study to investigate the epidemiology of primary dystonia and its clinical variants in an adult population. Methods: A Botulinum Toxin Clinic-based study was conducted in the period 18 May through 8 October 2010 in East China. We identified 523 dystonia patients from the Movement disorders and Botulinum Toxin clinic Cases. Results: The most common focal dystonia were blepharospasm (59%, cervical dystonia (35%, limb dystonia (3%, oromandibular dystonia (2% and laryngeal dystonia (1%. Males with primary dystonia were noted to have earlier age of onset. A female predominance was noted for most of the primary dystonias with a male to female ratio (M : F ranging from 1 : 1.48 to 1 : 3. Conclusions: The epidemiological features of dystonia in East China we collected were similar to the report in Japan which contrasts partly with that reported in Europe.

  20. Pump characteristics and applications

    CERN Document Server

    Volk, Michael

    2013-01-01

    Providing a wealth of information on pumps and pump systems, Pump Characteristics and Applications, Third Edition details how pump equipment is selected, sized, operated, maintained, and repaired. The book identifies the key components of pumps and pump accessories, introduces the basics of pump and system hydraulics as well as more advanced hydraulic topics, and details various pump types, as well as special materials on seals, motors, variable frequency drives, and other pump-related subjects. It uses example problems throughout the text, reinforcing the practical application of the formulae

  1. Robust primary modulation-based scatter estimation for cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Ritschl, Ludwig, E-mail: ludwig.ritschl@ziehm-eu.com [Ziehm Imaging, Nürnberg 90451 (Germany); Fahrig, Rebecca [Radiological Science Laboratory, Stanford University, 1201 Welch Road Palo Alto, Stanford, California 94304 (United States); Knaup, Michael; Maier, Joscha; Kachelrieß, Marc [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120 (Germany)

    2015-01-15

    Purpose: Scattered radiation is one of the major problems facing image quality in flat detector cone-beam computed tomography (CBCT). Previously, a new scatter estimation and correction method using primary beam modulation has been proposed. The original image processing technique used a frequency-domain-based analysis, which proved to be sensitive to the accuracy of the modulator pattern both spatially and in amplitude as well as to the frequency of the modulation pattern. In addition, it cannot account for penumbra effects that occur, for example, due to the finite focal spot size and the scatter estimate can be degraded by high-frequency components of the primary image. Methods: In this paper, the authors present a new way to estimate the scatter using primary modulation. It is less sensitive to modulator nonidealities and most importantly can handle arbitrary modulator shapes and changes in modulator attenuation. The main idea is that the scatter estimation can be expressed as an optimization problem, which yields a separation of the scatter and the primary image. The method is evaluated using simulated and experimental CBCT data. The scattering properties of the modulator itself are analyzed using a Monte Carlo simulation. Results: All reconstructions show strong improvements of image quality. To quantify the results, all images are compared to reference images (ideal simulations and collimated scans). Conclusions: The proposed modulator-based scatter reduction algorithm may open the field of flat detector-based imaging to become a quantitative modality. This may have significant impact on C-arm imaging and on image-guided radiation therapy.

  2. Development of web-based integrity evaluation system for primary components in a nuclear power plant

    International Nuclear Information System (INIS)

    A nuclear power plant is composed of a number of primary components. Maintaining the integrity of these components is one of the most critical issues in nuclear industry. In order to maintain the integrity of these primary components, a complicated procedure is required including periodical in-service inspection, failure assessment, fracture mechanics analysis, etc. Also, experts in different fields have to co-operate to resolve the integrity issues on the basis of inspection results. This integrity evaluation process usually takes long, and thus, is detrimental for the plant productivity. Therefore, an effective safety evaluation system is essential to manage integrity issues on a nuclear power plant. In this paper, a web-based integrity evaluation system for primary components in a nuclear power plant is proposed. The proposed system, which is named as WEBIES (web-based integrity evaluation system), has been developed in the form of 3-tier system architecture. The system consists of three servers; application program server, user interface program server and data warehouse server. The application program server includes the defect acceptance analysis module and the fracture mechanics analysis module which are programmed on the basis of ASME sec. XI, appendix A. The data warehouse server provides data for the integrity evaluation including material properties, geometry information, inspection data and stress data. The user interface program server provides information to all co- workers in the field of integrity evaluation. The developed system provides engineering knowledge-based information and concurrent and collaborative working environment through internet, and thus, is expected to raise the efficiency of integrity evaluation procedures on primary components of a nuclear power plant. (orig.)

  3. Magnetic buoyancy instabilities in the presence of magnetic flux pumping at the base of the solar convection zone

    CERN Document Server

    Barker, Adrian J; Proctor, Michael R E; Weiss, Nigel O

    2012-01-01

    We perform idealised numerical simulations of magnetic buoyancy instabilities in a model of the solar tachocline. We introduce a simplified model of magnetic flux pumping in an upper layer (the convection zone), and study the effects of its inclusion on the evolution of buoyancy instabilities in a lower layer (the radiative interior). We study its effects on the instability of both a preconceived magnetic slab and of a shear-generated magnetic layer. In the former, we find that in the regime in which the downward pumping velocity is comparable with the Alfven speed of the magnetic layer, flux pumping is able to hold back the bulk of the magnetic field, with only small pockets of strong field able to rise into the upper layer. In simulations in which the magnetic layer is generated by shear, we find that the shear velocity is not necessarily required to exceed that of the pumping (therefore the kinetic energy of the shear is not required to exceed that of the overlying convection), for strong localised pockets...

  4. Use of proton pump inhibitors and risk of hip/femur fracture: a population-based case-control study

    NARCIS (Netherlands)

    S. Pouwels (Sander); A. Lalmohamed (Arief); P. Souverein (Patrick); C. Cooper (Charles); B.J. Veldt (Bart); H.G.M. Leufkens (Hubert); A. de Boer (Anthonius); T.P. van Staa (Tjeerd); F. de Vries (Frank)

    2010-01-01

    textabstractSummary: Previous studies evaluated the association between proton pump inhibitor (PPI) use and subsequent fracture risk, but they showed ambiguous results. Therefore, the objective was to evaluate this association in a different study population. Our findings show that there is probably

  5. Heat pump control method based on direct measurement of evaporation pressure to improve energy efficiency and indoor air temperature stability at a low cooling load condition

    International Nuclear Information System (INIS)

    Highlights: • New heat pump control method was developed. • Experimental investigation on performance of heat pump with various control method. • New control method appeared to improve the stability of indoor air temperature. • New control method appeared to have a potential to reduce power consumption. - Abstract: The control systems of conventional heat pumps have an input of refrigerant temperature at the evaporator outlet to maintain superheat at proper level. In order to develop a control method that can be used to achieve better indoor thermal comfort and energy efficiency at a low cooling load condition than the current control method, a new method of the evaporation pressure control based on the evaporator outlet pressure reading (EPCP) was developed. The changes in the stability of indoor air temperature and power consumption were measured while changing the compressor frequency in accordance with the new control method. Compared with the evaporation pressure control based on the evaporator outlet temperature reading, the EPCP control method appeared to improve the stability of room air temperature or occupant thermal comfort significantly

  6. Inquiry-based science education: towards a pedagogical framework for primary school teachers

    Science.gov (United States)

    van Uum, Martina S. J.; Verhoeff, Roald P.; Peeters, Marieke

    2016-02-01

    Inquiry-based science education (IBSE) has been promoted as an inspiring way of learning science by engaging pupils in designing and conducting their own scientific investigations. For primary school teachers, the open nature of IBSE poses challenges as they often lack experience in supporting their pupils during the different phases of an open IBSE project, such as formulating a research question and designing and conducting an investigation. The current study aims to meet these challenges by presenting a pedagogical framework in which four domains of scientific knowledge are addressed in seven phases of inquiry. The framework is based on video analyses of pedagogical interventions by primary school teachers participating in open IBSE projects. Our results show that teachers can guide their pupils successfully through the process of open inquiry by explicitly addressing the conceptual, epistemic, social and/or procedural domain of scientific knowledge in the subsequent phases of inquiry. The paper concludes by suggesting further research to validate our framework and to develop a pedagogy for primary school teachers to guide their pupils through the different phases of open inquiry.

  7. Primary Teachers' Reflections on Inquiry- and Context-Based Science Education

    Science.gov (United States)

    Walan, Susanne; Mc Ewen, Birgitta

    2016-03-01

    Inquiry- and context-based teaching strategies have been proven to stimulate and motivate students' interests in learning science. In this study, 12 teachers reflected on these strategies after using them in primary schools. The teachers participated in a continuous professional development (CPD) programme. During the programme, they were also introduced to a teaching model from a European project, where inquiry- and context-based education (IC-BaSE) strategies were fused. The research question related to teachers' reflections on these teaching strategies, and whether they found the model to be useful in primary schools after testing it with their students. Data collection was performed during the CPD programme and consisted of audio-recorded group discussions, individual portfolios and field notes collected by researchers. Results showed that compared with using only one instructional strategy, teachers found the new teaching model to be a useful complement. However, their discussions also showed that they did not reflect on choices of strategies or purposes and aims relating to students' understanding, or the content to be taught. Before the CPD programme, teachers discussed the use of inquiry mainly from the aspect that students enjoy practical work. After the programme, they identified additional reasons for using inquiry and discussed the importance of knowing why inquiry is performed. However, to develop teachers' knowledge of instructional strategies as well as purposes for using certain strategies, there is need for further investigations among primary school teachers.

  8. Optimal design and experiment of long axis centrifugal pump based on differ head%基于不等扬程的离心式长轴泵的优化设计与试验

    Institute of Scientific and Technical Information of China (English)

    朱荣生; 贺博; 付强; 王秀礼; 张亮亮

    2015-01-01

    wrap angle, blade outlet angle,impeller outlet width, impeller outlet with a mean diameter and impeller outlet tilt angle were done by using the orthogonal design method. With the result of an orthogonal test method studied by range analysis, we obtained the primary and secondary order of the impeller geometric parameters which affect the head and efficiency of a long axis centrifugal pump. The primary and secondary order of the factors affecting the efficiency of the design point is blade number > blade outlet angle>impeller outlet width> impeller outlet tilt angle> blade wrap angle>impeller outlet with a mean diameter>impeller inlet diameter, The primary and secondary order of the factors affecting the head of the design point is > blade outlet angle > impeller outlet tilt angle > impeller outlet with a mean diameter > blade wrap angle > impeller outlet width > impeller inlet diameter,According to the orthogonal results, what is needed to get the final optimal combination are as follows: impeller inlet diameter is 345mm, blade number is 6, blade wrap angle is105°,blade outlet angle is 25°,impeller outlet width is 75mm, impeller outlet with a mean diameter is 550mm, impeller outlet tilt angle is 25°. Based on results of the orthogonal design, considering the affections of primary and secondary order of the factors on the efficiency and head, using the control variable method, greater impact parameters on pump performance must be chosen to optimize. Ignoring the effect of the blade number, 6 blades were selected. Then, we changed the unlimited blade number theoretical head of impeller shroud and unlimited blade number theoretical head of impeller hub on the basis of a head difference theory, controlled the secondary parameters unchanged, and then changed blade outlet angle to make all streamlines have the same limited blade number theoretical head. Five different impellers were designed according to the above method, 3D models of different impellers were made by

  9. High-Beam-Quality All-Solid-State 355 nm Ultraviolet Pulsed Laser Based on a Master-Oscillator Power-Amplifier System Pumped at 888 nm

    Science.gov (United States)

    Hong, Hailong; Liu, Qiang; Huang, Lei; Gong, Mali

    2012-09-01

    An efficient all-solid-state 355 nm ultraviolet laser based on an 888 nm pumped master-oscillator power-amplifier (MOPA) system is presented. Due to the high beam quality of the fundamental wave being superior to 1.15 (M2) under all pump powers and pulse repetition frequencies (PRFs), the UV laser has the advantage of being able to operate continuously from zero to maximum power. The maximum green and UV output powers were 45.9 W at 50 kHz and 24.3 W at 65 kHz with the corresponding conversion efficiencies from IR-to-green and IR-to-UV of 66.0% and 34.1%, respectively.

  10. 基于QFD和TRIZ的抽油机概念设计方法%The Conceptual Design Method for a Pumping Unit Based on QFD and TRIZ

    Institute of Scientific and Technical Information of China (English)

    张鹏; 盖峰; 管虹翔; 李萍

    2005-01-01

    Quality function deployment (QFD) is a quality system,that can help to design novel products that meet customers' needs. Theory of inventive problem solving (TRIZ) is a very powerful tool in helping to solve difficult technical problems encountered in the design process. Introducing QFD and TRIZ into the conceptual design of the pumping unit combines advantages of these two theories, therefore meeting different demands of different users. It can tell us "What should we do it" with QFD and "How should we do it" with TRIZ. The conceptual design method, which is based on QFD and TRIZ, is introduced and used to analyze and evaluate the conceptual design project of a pumping unit.

  11. Entropy, pricing and macroeconomics of pumped-storage systems

    Science.gov (United States)

    Karakatsanis, Georgios; Mamassis, Nikos; Koutsoyiannis, Demetris; Efstratiadis, Andreas

    2014-05-01

    We propose a pricing scheme for the enhancement of macroeconomic performance of pumped-storage systems, based on the statistical properties of both geophysical and economic variables. The main argument consists in the need of a context of economic values concerning the hub energy resource; defined as the resource that comprises the reference energy currency for all involved renewable energy sources (RES) and discounts all related uncertainty. In the case of pumped-storage systems the hub resource is the reservoir's water, as a benchmark for all connected intermittent RES. The uncertainty of all involved natural and economic processes is statistically quantifiable by entropy. It is the relation between the entropies of all involved RES that shapes the macroeconomic state of the integrated pumped-storage system. Consequently, there must be consideration on the entropy of wind, solar and precipitation patterns, as well as on the entropy of economic processes -such as demand preferences on either current energy use or storage for future availability. For pumped-storage macroeconomics, a price on the reservoir's capacity scarcity should also be imposed in order to shape a pricing field with upper and lower limits for the long-term stability of the pricing range and positive net energy benefits, which is the primary issue of the generalized deployment of pumped-storage technology. Keywords: Entropy, uncertainty, pricing, hub energy resource, RES, energy storage, capacity scarcity, macroeconomics

  12. 基于Visual Basic编程对离心泵性能曲线的拟合%Fitting Centrifugal Pump Performance Curve Based on Visual Basic

    Institute of Scientific and Technical Information of China (English)

    刘红明; 孙铁; 刘嵩; 王亮; 魏佳广

    2014-01-01

    在分析拟合离心泵性能曲线必要性的基础上,以拟合离心泵流量和扬程性能曲线为例,介绍了利用最小二乘法使用visual Basic语言进行直接编程拟合曲线的方法;经实际使用本程序具有简单、易用、求解效率高、适用范围广等特点,有效解决了石化行业中离心泵选型、试验中曲线拟合的数据处理问题,可以在离心泵及容积泵性能曲线拟合中推广应用。%Centrifugal pump performance curve is the basis of measuring the performance, type selection calculation and optimal operation of the centrifugal pump. After the test,in order to get more accurate data based on the sampling point, curve of experimental data needs to be fitted. In this paper, taking fitting flow and head curve of centrifugal pump as an example, the method to fit the curve by programming based visual basic with the least square method was introduced. The practical application has proved that the method has many advantages, and can effectively solve data processing problems in centrifugal pump type selection and curve fitting in petrochemical industry.

  13. Evidence-based medicine in primary care: qualitative study of family physicians

    Directory of Open Access Journals (Sweden)

    Dantas Guilherme

    2003-05-01

    Full Text Available Abstract Background The objectives of this study were: a to examine physician attitudes to and experience of the practice of evidence-based medicine (EBM in primary care; b to investigate the influence of patient preferences on clinical decision-making; and c to explore the role of intuition in family practice. Method Qualitative analysis of semi-structured interviews of 15 family physicians purposively selected from respondents to a national survey on EBM mailed to a random sample of Canadian family physicians. Results Participants mainly welcomed the promotion of EBM in the primary care setting. A significant number of barriers and limitations to the implementation of EBM were identified. EBM is perceived by some physicians as a devaluation of the 'art of medicine' and a threat to their professional/clinical autonomy. Issues regarding the trustworthiness and credibility of evidence were of great concern, especially with respect to the influence of the pharmaceutical industry. Attempts to become more evidence-based often result in the experience of conflicts. Patient factors exert a powerful influence on clinical decision-making and can serve as trumps to research evidence. A widespread belief that intuition plays a vital role in primary care reinforced views that research evidence must be considered alongside other factors such as patient preferences and the clinical judgement and experience of the physician. Discussion Primary care physicians are increasingly keen to consider research evidence in clinical decision-making, but there are significant concerns about the current model of EBM. Our findings support the proposed revisions to EBM wherein greater emphasis is placed on clinical expertise and patient preferences, both of which remain powerful influences on physician behaviour.

  14. PUMP: analog-hybrid reactor coolant hydraulic transient model

    International Nuclear Information System (INIS)

    The PUMP hybrid computer code simulates flow and pressure distribution; it is used to determine real time response to starting and tripping all combinations of PWR reactor coolant pumps in a closed, pressurized, four-pump, two-loop primary system. The simulation includes the description of flow, pressure, speed, and torque relationships derived through pump affinity laws and from vendor-supplied pump zone maps to describe pump dynamic characteristics. The program affords great flexibility in the type of transients that can be simulated

  15. Solar pumped solid state lasers

    International Nuclear Information System (INIS)

    Results are presented for direct solar pumping of a Nd:YAG rod laser. Stable CW output of more than 60 watts was obtained with slope efficiencies exceeding 2%. Results are consistent with predictions based on a simple solar laser model the authors have developed. Using this model, performance projections and design concepts for higher power and higher efficiency solar-pumped solid state lasers are presented. It is shown that existing laser materials with broadband absorption characteristics (e.g., alexandrite and Nd:Cr:GSGG) can have better than 10% overall conversion efficiencies when solar pumped. The utility of solar lasers for various laser applications in space is briefly discussed

  16. Chemically driven electron tunnelling pumps

    CERN Document Server

    Goychuk, I

    2006-01-01

    The simplest mechanism for molecular electron pumps is discussed which is based on nonadiabatic electron tunnelling and nonequilibrium conformational fluctuations. Such fluctuations can be induced, e.g. by random binding of negatively charged ATP molecules to the electron-transferring molecular complex, their subsequent hydrolysis and the products dissociation. The pumping rate can be controlled by the ATP concentration in solution. Depending on the model parameters there may exist a critical ATP concentration for the pump to function. Alternatively, nonequilibrium fluctuations can be induced by externally applied stochastic electric fields. For realistically chosen parameters, the mechanism is shown to be robust and highly efficient.

  17. Surface micromachined electrostatically actuated micro peristaltic pump

    OpenAIRE

    Xie, Jun; Shih, Jason; Lin, Qiao; Yang, Bozhi; Tai, Yu-Chong

    2004-01-01

    An electrostatically actuated micro peristaltic pump is reported. The micro pump is entirely surface micromachined using a multilayer parylene technology. Taking advantage of the multilayer technology, the micro pump design enables the pumped fluid to be isolated from the electric field. Electrostatic actuation of the parylene membrane using both DC and AC voltages was demonstrated and applied to fluid pumping based on a 3-phase peristaltic sequence. A maximum flow rate of 1.7 nL min^–1 and a...

  18. Cavitation Effects in Centrifugal Pumps- A Review

    Directory of Open Access Journals (Sweden)

    Maxime Binama

    2016-05-01

    Full Text Available Cavitation is one of the most challenging fluid flow abnormalities leading to detrimental effects on both the centrifugal pump flow behaviors and physical characteristics. Centrifugal pumps’ most low pressure zones are the first cavitation victims, where cavitation manifests itself in form of pitting on the pump internal solid walls, accompanied by noise and vibration, all leading to the pump hydraulic performance degradation. In the present article, a general description of centrifugal pump performance and related parameters is presented. Based on the literature survey, some light were shed on fundamental cavitation features; where different aspects relating to cavitation in centrifugal pumps were briefly discussed

  19. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  20. Prediction of performance of centrifugal pumps during starts under pressure

    Science.gov (United States)

    Rostafinski, W.

    1969-01-01

    Method which calculates start-up characteristics of centrifugal pumps reveals a capacity to predict pressure drop characteristics of pumps with vaned diffusers. Calculations are based on pump geometry, design-point flow, speed, and pressure rise, and the pump characteristic within range of approximately ten percent of the design-point flow.

  1. Methodology to monitor and diagnostic vibrations of the motor-pumps used in the primary cooling system of IEAR-1 nuclear research reactor; Metodologia para monitoracao e diagnostico de vibracao das bombas moto-operadas do circuito primario de refrigeracao do Reator IEA-R1

    Energy Technology Data Exchange (ETDEWEB)

    Benevenuti, Erion de Lima

    2004-07-01

    The objectives of this study are to establish a strategy to monitor and diagnose vibrations of the motor pumps used in the primary reactor cooling system of the IEA-R1 nuclear research reactor, to verify the possibility of using the existing installed monitoring vibration system and to implement such strategy in a continuous way. Four types of mechanical problems were considered: unbalancing, misalignment, gaps and faults in bearings. An adequate set of analysis tools, well established by the industry, was selected. These are: global measurements of vibration, velocity spectrum and acceleration envelope spectrum. Three sources of data and information were used; the data measured from the primary pumps, experimental results obtained with a Spectra Quest machine used to simulate mechanical defects and data from the literature. The results show that, for the specific case of the motor-pumps of IEA-R1 nuclear research reactor, although the technique using the envelope of acceleration, which is not available in the current system used to monitor the vibration of the motor pumps, is the one with best performance, the other techniques available in the system are sufficient to monitor the four types of mechanical problems mentioned. The proposed strategy is shown and detailed in this work. (author)

  2. 基于AMESim的尾气处理泵的仿真与优化设计%AMESim Based Simulation and Optimized Design of Exhaust Handing Pump

    Institute of Scientific and Technical Information of China (English)

    麦云飞; 王锐

    2015-01-01

    AMESim软件为机械、流体、电磁等工程系统提供了一个高性能的仿真平台。在对汽车尾气处理泵的工作原理与数学模型进行分析的基础上,通过AM ESim建立该泵的仿真模型,并在不同参数下进行动态仿真分析。仿真结果表明:采用膜片单向阀替换普通球阀以及适当增大弹簧的刚度可以提高泵的输出特性。%AMESim software provides a high performance simulation platform for the mechanical , fluid and electromagnetic engineering system .Based on the analysis on the working principle and mathematical model of an exhaust handing pump for automobile ,the dynamic simulation model of the pump is set up by AMESim ,and the dynamic simulation is conducted .The results show that using a diaphragm valve to replace the ordinary ball valve and properly increasing the spring stiffness can improve the output characteristics of the pump .

  3. Lab on a chip-based hepatic sinusoidal system simulator for optimal primary hepatocyte culture.

    Science.gov (United States)

    Choi, Yoon Young; Kim, Jaehyung; Lee, Sang-Hoon; Kim, Dong-Sik

    2016-08-01

    Primary hepatocyte cultures have been used in studies on liver disease, physiology, and pharmacology. While they are an important tool for in vitro liver studies, maintaining liver-specific characteristics of hepatocytes in vitro is difficult, as these cells rapidly lose their unique characteristics and functions. Portal flow is an important condition to preserve primary hepatocyte functions and liver regeneration in vivo. We have developed a microfluidic chip that does not require bulky peripheral devices or an external power source to investigate the relationship between hepatocyte functional maintenance and flow rates. In our culture system, two types of microfluidic devices were used as scaffolds: a monolayer- and a concave chamber-based device. Under flow conditions, our chips improved albumin and urea secretion rates after 13 days compared to that of the static chips. Reverse transcription polymerase chain reaction demonstrated that hepatocyte-specific gene expression was significantly higher at 13 days under flow conditions than when using static chips. For both two-dimensional and three-dimensional culture on the chips, flow resulted in the best performance of the hepatocyte culture in vitro. We demonstrated that flow improves the viability and efficiency of long-term culture of primary hepatocytes and plays a key role in hepatocyte function. These results suggest that this flow system has the potential for long-term hepatocyte cultures as well as a technique for three-dimensional culture. PMID:27334878

  4. An innovative sludge management system based on separation of primary and secondary sludge treatment.

    Science.gov (United States)

    Mininni, G; Braguglia, C M; Ramadori, R; Tomei, M C

    2004-01-01

    An innovative sludge management system based on separation of treatment and disposal of primary and secondary sludge is discussed with reference to a sewage treatment plant of 500,000 equivalent person capacity. Secondary sludge, if treated separately from primary sludge, can be recovered in agriculture considering its relatively high content of nitrogen and phosphorus and negligible presence of pathogens and micropollutants. One typical outlet for primary sludge is still incineration which can be optimised by rendering the process auto thermal and significantly reducing the size of the incineration plant units (dryer, fluidised bed furnace, boiler and units for exhaust gas treatment) in comparison with those required for mixed sludge incineration. Biogas produced in anaerobic digestion is totally available for energy conversion when sludge treatment separation is performed, while in the other case a large proportion may be used as fuel in incineration, thus reducing the net electric energy conversion from 0.85-0.9 to 0.35-0.4 MW for the plant considered. PMID:15581006

  5. Performance Analysis of Mean Value-Based Power Allocation with Primary User Interference in Spectrum Sharing Systems

    OpenAIRE

    Duan, Ruifeng; Jäntti, Riku; Elmusrati, Mohammed S.

    2014-01-01

    In this paper, we provide an exact expression for the ergodic capacity of the secondary user, and a unified closed-form expression for its bounds with taking the consideration of the primary interference at the secondary receiver. In addition, a simple but accurate approximation of the the ergodic capacity of the primary user is presented. Moreover, a primary user capacity loss based power allocation scheme for the secondary user is also proposed. Finally, we compare the performance of the tw...

  6. A green laser at 517 nm based on intracavity frequency doubling of the diode-pumped Yb:LO laser

    Science.gov (United States)

    Li, Yong-liang; Li, Xiu-fei; Hu, Hong-wei; Hai, Xiao-quan; Liu, Yang; Wang, Jin-nan

    2014-09-01

    We report for the first time, to our knowledge, the diode-pumped continuous-wave (CW) thin-disk Yb3+-doped Lu2O3 (Yb:LO) laser at 1 034 nm and the second-harmonic generation at 517 nm. With a 6.3% output coupler, the maximum output power is 1.17 W under a pump power of 18.5 W. Moreover, the intracavity second-harmonic generation (SHG) is also achieved with power of 193 mW at 517 nm by using an LiB3O5 (LBO) nonlinear crystal. The beam quality factor M 2 is about 1.28. The fluctuation of the output power is about 3% in 1 h.

  7. A methodology to predict the uniformity of double-shell waste slurries based on mixer pump operation

    International Nuclear Information System (INIS)

    Dimensional analysis is used to determine the similarity parameters that describe the uniformity of radioactive slurry wastes to be suspended by mixer pumps. The results of this analysis are applied to the design of scaled experiments that will determine the operating parameters that will ensure an adequately uniform feed stream during waste retrieval from Hanford double-shell tanks. Ten dimensionless parameters describing the slurry mixing process were identified. Of these, three describe purely geometric features, three describe slurry properties only, one is a dimensionless time scale, and three describe important dynamic factors. The three parameters describing the dynamic features are the Reynolds number, which describes the degree of turbulence in the tank; the Froude number, which describes the effects of stratification on the circulation patterns; and the gravitational settling number, which describes the balance between the work done by gravity to cause settling and the work done by the pump to resuspend particles

  8. Magnetic buoyancy instabilities in the presence of magnetic flux pumping at the base of the solar convection zone

    OpenAIRE

    Barker, A.J.; Silvers, L. J.; Proctor, M. R. E.; Weiss, N.O.

    2012-01-01

    We perform idealized numerical simulations of magnetic buoyancy instabilities in three dimensions, solving the equations of compressible magnetohydrodynamics in a model of the solar tachocline. In particular, we study the effects of including a highly simplified model of magnetic flux pumping in an upper layer (‘the convection zone’) on magnetic buoyancy instabilities in a lower layer (‘the upper parts of the radiative interior – including the tachocline’), to study these competing flux trans...

  9. Outcome of eating disorders in a primary care-based study.

    OpenAIRE

    Son, G. van; Hoeken, D. van; Furth, E. van; Donker, G.; Hoek, H.

    2009-01-01

    Purpose: Most outcome studies of eating disorders are based on samples of patients that had entered specialized mental health care. This might be a group that does not represent all patients with an eating disorder and possibly shows a different course and outcome. Little is known about the outcome of newly diagnosed patients with an eating disorder in primary care. Method: We studied the course and outcome of eating disorders in a nationwide 3–7 year follow-up study of patients detected in p...

  10. Case Report: Liquid-based cytology aids in primary fallopian tube cancer diagnosis

    Institute of Scientific and Technical Information of China (English)

    Zhuo REN; Yun-ping ZHANG; Hui-xia YANG; Li-rong ZHU

    2009-01-01

    Primary fallopian tube carcinoma (PFTC) is a rare malignant carcinoma among all genital tract malignancies. It occurs most commonly in postmenopausal women and is similar to ovarian malignancy historically and clinically. Because of its insidious onset and silent course, the diagnosis is made usually postoperatively. Liquid-based cytology (LBC) is a type of method for cervical cancer screening, but sometimes it may aid in making PFTC diagnosis. We report a 47-year-old woman with PFTC, whose diagnosis was made with the aid of LBC.

  11. Coordinated Power Control Strategy based on Primary-Frequency-Signaling for Islanded Microgrids

    DEFF Research Database (Denmark)

    Wu, Dan; Guerrero, Josep M.; Vasquez, Juan Carlos;

    2013-01-01

    In a flexible microgrid, the power regulation of each electronic-converter-based unit should be not only determined by the load demand, but also controlled according to the power and energy available in each unit. This paper proposes a coordinated control strategy in which each unit can operate in...... different operation modes taking into account the resource limitation. Firstly, a Primary-Frequency-Signaling (PFS) is introduced to realize coordinated control between units in a distributed way. Then the whole control structure of system is descripted in detail, which includes innerloop control with...

  12. Switch Based Opportunistic Spectrum Access for General Primary User Traffic Model

    KAUST Repository

    Gaaloul, Fakhreddine

    2012-06-18

    This letter studies cognitive radio transceiver that can opportunistically use the available channels of primary user (PU). Specifically, we investigate and compare two different opportunistic channel access schemes. The first scheme applies when the secondary user (SU) has access to only one channel. The second scheme, based on channel switching mechanism, applies when the SU has access to multiple channels but can at a given time monitor and access only one channel. For these access schemes, we derive the exact analytical results for the novel performance metrics of average access time and average waiting time under general PU traffic models.

  13. Clinical analysis of multiple primary malignancies in the digestive system: A hospital-based study

    Institute of Scientific and Technical Information of China (English)

    Hui-Yun Cheng; Cheng-Hsin Chu; Wen-Hsiung Chang; Tzu-Chi Hsu; Shee-Chan Lin; Chuan-Chuan Liu; An-Ming Yang; Shou-Chuan Shih

    2005-01-01

    AIM: To analyze the characteristics of multiple primary malignancies (MPMs) of digestive system; including incidence, types of tumor combinations, time intervals between development of multiple tumors, clinical course,and prognostic factors affecting survival and mortality.METHODS: Data from a total of 129 patients treated from January 1991 to December 2000 for pathologically proved MPMs, including at least one originating from the digestive system, were reviewed retrospectively.RESULTS: Among 129 patients, 120 (93.02%) had two primary cancers and 9 (6.98%) had three primary cancers. The major sites of MPMs of the digestive system were large intestine, stomach, and liver. Associated nondigestive cancers included 40 cases of gynecological cancers, of which 31 were carcinoma of cervix and 10cases of genitourinary cancers, of which 5 were bladder cancers. Other cancers originated from the lung, breast,nasopharynx, larynx, thyroid, brain, muscle, and skin.Reproductive tract cancers, especially cervical, ovarian,bladder, and prostate cancers were the most commonly associated non-GI cancers, followed by cancer of the lung and breasts. Forty-three cases were synchronous, while the rest (86 cases) were metachronous cancers. Staging of MPMs and treatment regimes correlated with the prognosis between survival and non-survival groups.CONCLUSION: As advances in cancer therapy bring about a progressively larger percentage of long-term survivors, the proportion of patients with subsequent primary lesions will increase. Early diagnosis of these lesions, based on an awareness of the possibility of second and third cancers, and multidiscipiinary treatment strategies will substantially increase the survival of these patients.

  14. Disseminated primary diffuse leptomeningeal gliomatosis: a case report with liquid based and conventional smear cytology

    Directory of Open Access Journals (Sweden)

    Bilic Masha

    2005-09-01

    Full Text Available Abstract Background Primary diffuse leptomeningeal gliomatosis is a rare neoplasm confined to the meninges without evidence of primary tumor in the brain or spinal cord parenchyma. Cerebrospinal fluid diversion via ventriculoperitoneal shunt may be used as a therapeutic modality. Herein, we describe the first report of cytologic findings of a case of this neoplasm with shunt-related peritoneal metastasis. Case presentation A 19-year-old male presented with a 6-month history of severe headaches. He had bilateral papilledema on physical exam. Cerebrospinal fluid examination was negative. Four months later a ventriculoperitoneal shunt was placed. Shortly thereafter, he was diagnosed with primary diffuse leptomeningeal gliomatosis based on the biopsy of an intradural extramedullary lesion adjacent to the lumbar spinal cord at a referral cancer center. The histology featured an infiltrating growth pattern of pleomorphic astrocytes with diffuse positivity for glial fibrillary acidic protein. A couple of months later he presented at our institution with ascites and an anterior peritoneal mass. Repeat cerebrospinal fluid cytology and fine needle aspiration of the mass confirmed disseminated gliomatosis. Cytologic characteristics included clusters of anaplastic cells of variable size, high nuclear to cytoplasm ratio and scant to moderate cytoplasm. Occasional single bizarre multinucleated cells were seen with eccentric "partial wreath-like" nuclei, clumped chromatin and prominent nucleoli. Patient expired 13 months after initial presentation. Conclusion Disseminated primary diffuse leptomeningeal gliomatosis should be considered in the differential diagnosis of chronic aseptic meningitis and in the presence of a peritoneal tumor in patients with ventriculoperitoneal shunts. Immunocytochemistry may be of diagnostic value.

  15. Stirling Engine Heat Pump

    Science.gov (United States)

    Kagawa, Noboru

    Recent advances in the feasibility studies related to the Stirling engines and Stirling engine heat pumps which have been considered attractive due to their promising role in helping to solve the global environmental and energy problems,are reviewed. This article begins to describe the brief history of the Stirling engines and theoretical thermodynamic analysis of the Stirling cycle in order to understand several advantages on the Stirling engine. Furthermore,they could throw light on our question why the dream engines had not been promoted to practical applications during two hundred years. The present review shows that the Stirling engines with several unique advantages including 30 to 40% thermal efficiency and preferable exhaust characteristics,had been designed and constructed by recent tackling for the development of the advanced automobile and other applications using them. Based on the current state of art,it is being provided to push the Stirling engines combined with heat pumps based on the reversed Rankine cycle to the market. At present,however, many problems, especially for the durability, cost, and delicate engine parts must be enforced to solve. In addition,there are some possibilities which can increase the attractiveness of the Stirling engines and heat pumps. The review closes with suggestions for further research.

  16. Adapting evidence-based, cognitive-behavioral interventions for anxiety for use with adults in integrated primary care settings.

    Science.gov (United States)

    Shepardson, Robyn L; Funderburk, Jennifer S; Weisberg, Risa B

    2016-06-01

    Evidence-based treatments for adult patients with anxiety are greatly needed within primary care settings. Psychotherapy protocols, including those for cognitive-behavioral therapy (CBT), are often disorder-specific and were developed for specialty mental health settings, rendering them infeasible in primary care. Behavioral health consultants (BHCs) integrated into primary care settings are uniquely positioned to provide anxiety treatment. However, due to the dearth of empirically supported brief treatments for anxiety, BHCs are tasked with adapting existing treatments for use in primary care, which is quite challenging due to the abbreviated format and population-based approach to care. CBT protocols are highly effective in the treatment of anxiety and fit well with the self-management emphasis of integrated primary care. We review the rationale and procedure for 6 evidence-based CBT intervention techniques (psycho-education, mindfulness and acceptance-based behavioral techniques, relaxation training, exposure, cognitive restructuring, and behavioral activation) that can be adapted for use in the brief format typical of integrated primary care. We offer tips based on our clinical experience, highlight resources (e.g., handouts, websites, apps), and discuss 2 case examples to aid BHCs in their everyday practice. Our goal is to provide BHCs with practical knowledge that will facilitate the use of evidence-based interventions to improve the treatment of anxiety in primary care settings. (PsycINFO Database Record PMID:27064434

  17. Model-based analysis of patterned motion processing in mouse primary visual cortex

    Directory of Open Access Journals (Sweden)

    Dylan Richard Muir

    2015-08-01

    Full Text Available Neurons in sensory areas of neocortex show responses tuned to specific features of the environment. In visual cortex, information about features such as edges or textures with particular orientations must be integrated to recognize a visual scene or object. Connectivity studies in rodent cortex have revealed that neurons make specific connections within sub-networks sharing common input tuning. In principle, this sub-network architecture enables local cortical circuits to integrate sensory information. However, whether feature integration indeed occurs locally in rodent primary sensory areas has not been examined directly. We studied local integration of sensory features in primary visual cortex (V1 of the mouse by presenting drifting grating and plaid stimuli, while recording the activity of neuronal populations with two-photon calcium imaging. Using a Bayesian model-based analysis framework, we classified single-cell responses as being selective for either individual grating components or for moving plaid patterns. Rather than relying on trial-averaged responses, our model-based framework takes into account single-trial responses and can easily be extended to consider any number of arbitrary predictive models. Our analysis method was able to successfully classify significantly more responses than traditional partial correlation analysis, and provides a rigorous statistical framework to rank any number of models and reject poorly performing models. We also found large a proportion of cells that respond strongly to only one stimulus class. In addition, a quarter of selectively responding neurons had more complex responses that could not be explained by any simple integration model. Our results show that a broad range of pattern integration processes takes place already at the level of primary visual cortex. This diversity of integration is consistent with processing of visual inputs by local sub-networks within V1 that are tuned to combinations

  18. Stress corrosion cracking of nickel base alloys in PWR primary water

    International Nuclear Information System (INIS)

    Stress corrosion cracking (SCC) of nickel base alloys and associated weld metals in primary water is one of the major concerns for pressurized water reactors (PWR). Since the 90's, highly cold-worked stainless steels (non-sensitized) were also found to be susceptible to SCC in PWR primary water ([1], [2], [3]). In the context of the life extension of pressurized water reactors, laboratory studies are performed in order to evaluate the SCC behaviour of components made of nickel base alloys and of stainless steels. Some examples of these laboratory studies performed at CEA will be given in the talk. This presentation deals with both initiation and propagation of stress corrosion cracks. The aims of these studies is, on one hand, to obtain more data regarding initiation time or crack growth rate and, one the other hand, to improve our knowledge of the SCC mechanisms. The aim of these approaches is to model SCC and to predict components life duration. Crack growth rate (CGR) tests on Alloy 82 with and without post weld heat treatment are performed in PWR primary water (Figure 1). The heat treatment seems to be highly beneficial by decreasing the CGR. This result could be explained by the effect of thermal treatment on the grain boundary nano-scopic precipitation in Alloy 82 [4]. The susceptibility to SCC of cold worked austenitic stainless steels is also studied. It is shown that for a given cold-working procedure, SCC susceptibility increases with increasing cold-work ([2], [5]). Despite the fact that the SCC behaviour of Alloy 600 has been widely studied for many years, recent laboratory experiments and analysis ([6], [7], [8]) showed that oxygen diffusion is not a rate-limiting step in the SCC mechanism and that chromium diffusion in the bulk close the crack tip could be a key parameter. (authors)

  19. Water Pump Development for the EVA PLSS

    Science.gov (United States)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design, fabricate, and test a preflight prototype pump for use in the Extravehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump will accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting noncondensable gas without becoming "air locked." The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the preflight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES will simulate the vacuum environment in which the flight pump will operate. Testing will verify that the pump meets design requirements for range of flow rates, pressure rise, power consumption, working fluid temperature, operating time, and restart capability. Pump testing is currently

  20. Influence of problem-based teaching and learning of grammar on pupils’ attainment in primary school

    Directory of Open Access Journals (Sweden)

    Jocić Zorica

    2010-01-01

    Full Text Available With the purpose of getting an insight into the effects of problem-based teaching and learning, an experiment was carried out by using the method of parallel groups on the sample of 204 pupils in the third and sixth grade of primary school. The results of final knowledge assessment showed that problem-based teaching and learning of grammar had positive influence on pupils' attainment comparing to the usual way of learning grammar. A significant improvement has been achieved in the field of reproductive and productive grammar knowledge on the whole sample of pupils as well as on the subsamples of pupils in the third and sixth grade. Because of the limited time left for this experimental programme, the reproductive knowledge of pupils was bigger than the productive knowledge. It has been noticed that regarding the successfulness of solving the grammatical problems, there was no difference between the pupils of younger and older primary school age, in the situation when these problems were decided on according to their age and intellectual abilities. All pupils had made an improvement, but they remained within the range of their marks in Serbian language. In addition to this, better progress was made by the pupils with better marks in Serbian language. Girls were more successful than boys, but the difference between boys and girls was smaller regarding the reproductive knowledge than the productive knowledge.