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Sample records for auxiliary feedwater system

  1. System Study: Auxiliary Feedwater 1998-2014

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2015-12-01

    This report presents an unreliability evaluation of the auxiliary feedwater (AFW) system at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the AFW results.

  2. System Study: Auxiliary Feedwater 1998–2013

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2014-12-31

    This report presents an unreliability evaluation of the auxiliary feedwater (AFW) system at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the AFW results.

  3. Operating experiences and degradation detection for auxiliary feedwater systems

    International Nuclear Information System (INIS)

    A study of Pressurized Water Reactor Auxiliary Feedwater (AFW) Systems has been conducted by Oak Ridge National Laboratory (ORNL) under the auspices of the Nuclear Regulatory Commission's Nuclear Plant Aging Research Program. The results of the study are documented in NUREG/CR-5404, Vol. 1, Auxiliary Feedwater System Aging Study. The study reviewed historical failure experience and current monitoring practices for the AFW System. This paper provides an overview of the study approach and results

  4. Seismic qualification of PWR plant auxiliary feedwater systems

    International Nuclear Information System (INIS)

    The NRC Standard Review Plan specifies that the auxiliary feedwater (AFW) system of a pressurized water reactor (PWR) is a safeguard system that functions in the event of a Safe Shutdown Earthquake (SSE) to remove the decay heat via the steam generator. Only recently licensed PWR plants have an AFW system designed to the current Standard Review Plan specifications. The NRC devised the Multiplant Action Plan C-14 in order to make a survey of the seismic capability of the AFW systems of operating PWR plants. The purpose of this survey is to enable the NRC to make decisions regarding the need of requiring the licensees to upgrade the AFW systems to an SSE level of seismic capability. To implement the first phase of the C-14 plan, the NRC issued a Generic Letter (GL) 81-14 to all operating PWR licensees requesting information on the seismic capability of their AFW systems. This report summarizes Lawrence Livermore National Laboratory's efforts to assist the NRC in evaluating the status of seismic qualification of the AFW systems in 40 PWR plants, by reviewing the licensees' responses to GL 81-14

  5. Operation of the main feedwater system turbopump following plant trip with total failure of the auxiliary feedwater system

    International Nuclear Information System (INIS)

    The Auxiliary Feedwater System (AF) is a safeguard system which has been designed to supply feedwater to the steam generators, cool the primary system and remove decay heat from the reactor when the main feedwater pumps fail due to loss of power or any other reason. Thus, when plant trip occurs, the AF system pumps start up automatically, allowing removal of decay heat from the reactor. However, even though this system (2 motor-driven pumps and 1 turbopump) is highly reliable, injection of water to the steam generators must be ensured when it fails completely. To do this, if plant trip has not been caused by loss of off site power or failure of the Main Feedwater System (FW) turbopumps, one of these turbopumps can be used to achieve removal of decay heat. Since a large amount of steam is consumed by these turbopumps, an analysis has been performed to determine whether one of these pumps can be used and what actions are necessary to inject water into the steam generators. Results show that, for the case in question, a FW turbopump can be used to remove decay heat from the reactor. (author)

  6. Resolution of concerns in auxiliary feedwater piping

    International Nuclear Information System (INIS)

    Auxiliary feedwater piping systems at pressurized water reactor (PWR) nuclear power plants have experienced unanticipated operating conditions during plant operation. These unanticipated conditions have included plant events involving backleakage through check valves, temperatures in portions of the auxiliary feedwater piping system that exceed design conditions, and the occurrence of unanticipated severe fluid transients. The impact of these events has had an adverse effect at some nuclear stations on plant operation, installed plant components and hardware, and design basis calculations. Beaver Valley Unit 2, a three loop pressurized water reactor nuclear plant, has observed anomalies with the auxiliary feedwater system since the unit went operational in 1987. The consequences of these anomalies and plant events have been addressed and resolved for Beaver Valley Unit 2 by performing engineering and construction activities. These activities included pipe stress, pipe support and pipe rupture analysis, the monitoring of auxiliary feedwater system temperature and pressure, and the modification to plant piping, supports, valves, structures and operating procedures

  7. Equipment Reliability Improvement for Koeberg Nuclear Power Plant Auxiliary Feedwater System

    International Nuclear Information System (INIS)

    This paper investigated how the performance of the Koeberg Auxiliary Feedwater System could be improved using the 'maintenance rule'. As a conclusion, this paper figured out AFWS pumps and the TDP control circuit need special attention in improving the reliability of the AFWS, this lead to an improved maintenance strategy for the system. The purpose of this study is to apply maintenance rule to enhance the Auxiliary Feedwater System (AFWS) maintenance strategy at Koeberg Nuclear Power Plant (KNPP). Currently, Koeberg AFWS health status is red, needing an improvement. This study seeks to use maintenance rule to identify components that enable AFWS to fulfill its essential functions so as to focus maintenance resources and have the greatest beneficial impact on improving reliability and availability of the system

  8. PSA effect analysis of a design modification of the auxiliary feedwater system for a Westinghouse type plant

    International Nuclear Information System (INIS)

    The auxiliary feedwater system is an important system used to mitigate most accidents considered in probabilistic safety assessment (PSA). The reference plant has produced electric power for about thirty years. Due to age related deterioration and lack of parts, a turbine driven auxiliary feedwater pump (TD AFWP), some valves, and piping of the auxiliary feedwater system should be replaced. This change includes relocation of some valves, installation of valves for maintenance of the steam generator, and a new cross tie line. According to the design change, the Final Safety Analysis Report (FSAR) has been revised. Therefore, this design modification affects the PSA. It is thus necessary to assess the improvement of plant safety. In this paper, the impact of the design change of the auxiliary feedwater system on the PSA is assessed. The results demonstrate that this modification considering the plant safety decreased the total CDF

  9. Maintenance centered on reliability applied to a NPP auxiliary feedwater system

    International Nuclear Information System (INIS)

    The main objective of maintenance in a NPP is to assure that structures, systems and components will perform their design functions with reliability and/or availability in order to allow a safe and economic electric power generation. Reliability-Centered Maintenance (RCM) is a method of systematic review to either develop or optimize Preventive Maintenance Programs. This paper presents the objectives, concepts, organization and methods used in the application of RCM to NPP. Some application examples are include in this paper, considering some components of the Auxiliary Feedwater System of a generic Westinghouse designed two-loop PWR NPP. (author). 4 refs., 3 figs

  10. Probabilistic analysis of reactor safety - The auxiliary feedwater system of Angra I

    International Nuclear Information System (INIS)

    The unavailability of the auxiliary feedwater system (AFWS) of Angra-1, was calculated. The fault tree analysis technique was used, considering two diferent types of contribution to system unavailability: The one due to hard-ware failure and the contribution due to test and maintenance which was separately analysed. The COMBO-and SAMPLE computer codes were used. The results have shown that the AFWS of Angra-1 contains enough redundancy to guarantee a safe operation under the conditions analysed, best values having been obtained for the unavailability of AFWS of Angra 1 with those codes than with the WASH-1400. (E.G.)

  11. Feasibility study of helically coiled tube condensation heat exchanger for a passive auxiliary feedwater system

    International Nuclear Information System (INIS)

    The Passive Auxiliary Feedwater System (PAFS) with nearly-horizontal heat exchangers is one of passive safety features of APR+ (Advanced Power Reactor Plus) which provides the auxiliary feedwater by means of natural circulation with condensation. It is feasible to increase the heat transfer capacity of the PAFS by employing a helically coiled heat exchanger due to additional secondary flow effect by centrifugal force. In addition, a compact and flexible design can be achieved in a fixed volume by using the helically coiled heat exchanger, which is one of the most important merits of implementing this heat exchanger. In this paper, the helically coiled heat exchanger has been employed for the PAFS instead of nearly-horizontal heat exchanger. In order to evaluate the heat transfer performance of the helically coiled heat exchanger, an in-tube condensation heat transfer correlation by Wongwises has been introduced into the system analysis code, MARS-KS. A comparative numerical study was conducted for both heat exchangers. The result shows that helically coiled heat exchanger has 20% higher heat transfer efficiency than existing nearly-horizontal heat exchanger. (author)

  12. Feasibility Study on Passive Auxiliary Feedwater System in Loss of Condenser Vacuum Accident

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Soon Joon; Lee, Byung Chul [FNC Tech., Daejeon (Korea, Republic of); Cheon, Jong; Kim, Han Gon [NETEC, Daejeon (Korea, Republic of)

    2009-05-15

    Nuclear leading countries are developing and constructing technology intensive pressurized water reactors (PWRs) such as AP1000 (United State), EPR (Europe), and US-APWR (Japan), and these advanced reactors adopt several passive safety features in order to enhance the safety and reliability. Domestic advanced reactor APR1400 already completed the earlier development in 2002, and technology gap from the nuclear leading countries become large. In particular, China requires technology transfer in the order of new power plant construction. Thus it is expected difficult to export the power plant to the newly developing countries without our own technology. Therefore, the improvement of competitive power and establishment of infra structure of advanced nuclear industry through innovative technology enhancement are urgent and essential to international competitive marketing. Passive safety features have been always adopted as an improved design concept in the development of innovative reactor design. Domestic nuclear industry has stated the development of APR+ as a Korean specific reactor for the export strategy. In the development of APR+ a passive auxiliary feedwater system (PAFS) has been considered as a noticeable candidate of improved design. Reference 2 reported that the adoption of PAFS, which can replace the auxiliary feedwater system, can prevent core damage in the accident of station black out (SBO), since Class 1E DC power operates the related valves, and 8 hours hot standby operation of plant without operation action is achievable. This PAFS contributes to the safety and economics, in that it decreases the core damage frequency 26% from 2.45E- 06/r-y to 1.80E-06/r-y, and it saves the construction cost 20 million Kr-Won. This paper discusses on the performance of PAFS for the accident of loss of condenser vacuum as a precursor of detailed design specification.

  13. Single-tube condensation experiment in Passive Auxiliary Feedwater System of APR1400+

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chang Wook; No, Hee Cheon; Yun, Bong Yo; Jeon, Byong Guk [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2012-05-15

    Conventional Korean nuclear power plants, Advanced Power Reactors (APR), are characterized by an active cooling system. However, Active cooling system may not prevent significant damage without any AC power source available for its operation as vividly illustrated through the recent Fukushima incident. In the APR1400+ to be designed, an independent passive cooling system was added in order to overcome the aforementioned shortcomings. In the Passive Auxiliary Feedwater System (PAFS), gravity force and density difference between steam and water are used. The system comprises of 240 condensation tubes to efficiently remove decay heat. Before applying the PAFS to APR1400+, the system's safety and heat removal performance must be verified. The present study experimentally evaluates the heat removal performance of a single tube in the PAFS. The objectives of SCOP (Single-tube Condensation experiment facility of PAFS) are the evaluation of the heat removal performance in the tube of the PAFS and database construction under various tube designs and test conditions. Reaching these objectives, we developed advanced measurement techniques for the amount of moisture, heat flux, and water film thickness.

  14. Study on the importance and sensibility of the parameters used in the Angra-1 auxiliary feedwater system reliability analysis

    International Nuclear Information System (INIS)

    In this paper some procedures are presented in order to develop an importance and sensitivity analysis on the parameters considered in the reliability study of the Auxiliary Feedwater System of Angra-1. The importance analysis is performed to determine the events which have contribution on the top event. The results obtained from the sensitivity analysis can show the effects of variations in probability values of the dominant component failures on the probability of the top event. (author). 7 refs., 9 figs., 5 tabs

  15. A study on the mitigating capability of an auxiliary feedwater system during SBO for APR1400

    International Nuclear Information System (INIS)

    The objective of this paper is to establish an auxiliary feedwater (AFW) operational technical bases for the Korean Next Generation Reactor (APR1400) by modeling the plant, and by analyzing station blackout (SBO) using the MELCOR code. For the integrity of the reactor vessel and containment safety against severe accidents, it is essential to understand the severe accident sequences and to assess accident progression accurately using computer codes. Furthermore, it is important to attain the capability to analyze the advanced nuclear reactor design for the severe accident prevention and mitigation. Accident analyses are also undertaken to find out how effective AFW is mitigating in severe accident progresses. A nominal base case for SBO without AFW, time interval between feedwater stop and reactor vessel failure is 12,740 seconds. When AFW operates to mitigate the SBO accident progression 2, 4 and 8 hours after SBO starts, the reactor vessel failure is delayed for 20,415 seconds, 22,633 seconds and 26,508 seconds, respectively thus the operator has more time available for AC recovery and accident mitigation to prevent reactor vessel failure. (author)

  16. Application of reliability-centered maintenance to the auxiliary feedwater system at San Onofre Nuclear Generating Station

    International Nuclear Information System (INIS)

    Reliability-centered maintenance (RCM) is a systematic methodology for defining applicable and effective preventive maintenance (PM) tasks. In 1984, the Electric Power Research Institute (EPRI) studied the air transport industry's RCM program as a candidate for technology transfer to the nuclear power industry. EPRI initiated two RCM pilot projects that directly utilized the RCM methodology developed by the aviation industry. The first RCM application was to the component cooling water systems of Florida Power and Light's Turkey Point Units 3 and 4. The second application was to the main feedwater system at Duke Power's McGuire Station. The results of these studies clearly indicate the benefits of the system-oriented RCM approach, and many areas for cost-effective improvements to PM programs were identified. After the completion of these two pilot studies, Southern California Edison and EPRI initiated an application of RCM to the auxiliary feedwater (AFW) system at the San Onofre Nuclear Generating Station, Unit 2. In contrast to the previous EPRI-sponsored applications to normally operating systems, the AFW system is a standby safety system. The study results demonstrate the usefulness of extending the RCM methodology to standby safety systems. The specific results show promise of reducing the PM costs for the AFW system at San Onofre while maintaining highly reliable system performance. The recommendations from this study are currently being considered for implementation by the plant maintenance staff

  17. Evaluation of Effect of N{sub 2} Gas on the Cooling Capability of Passive Auxiliary Feedwater System (PAFS) in APR+

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yun Je; Kang, Kyong Ho; Yun, Byong Jo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In Korea, Advanced Power Reactor Plus (APR+) has being developed by adding passive safety features to Advanced Power Reactor 1400MWe (APR1400). Passive Auxiliary Feedwater System (PAFS) is one of passive system adopted in the APR+ to replace the conventional active auxiliary feedwater system. Because PAFS removes decay heat from the reactor core, it is required to verify the performance of PAFS in postulated accidents cases. In addition, an effect of noncondensable gas on the heat removal capability of PAFS should be evaluated since the non-condensable gas may deteriorate a condensation heat transfer through the condensation heat exchanger in PAFS. In this study, the effect of N{sub 2} gas was evaluated using MARS

  18. The analysis of the functional role of man and machine in the control of a notional auxiliary feedwater system

    International Nuclear Information System (INIS)

    We will describe here the simulation of a moderately complex plant, i.e. the Auxiliary Feedwater System (AFWS) of a nuclear power plant, which has been developed for interacting with a cognitive model of operator in a simulation framework of man-machine system studies as well as with an external operator for verifying and validating the hypotheses of the theoretical model by experimental studies. In order to develop such simulation, which must be very flexible for satisfying the needs of interaction with an operator as well as with a cognitive model, a number of special conditions have been respected: the model of functional behaviour of the system has been extended to include the logic of control mechanisms, i.e. components, indicators and actuators; the control tasks for a number of sequences has been developed; the robustness of physical model has been tested in whole possible configuration of the plant; and finally, the interface of the simulation with the model for dynamic failures of components has also been granted. In this paper, these aspects of the deterministic model of the AFWS will be firstly presented in detail. Then, the interface of the plant simulation with an external user or with the cognitive model of the operator will be described focusing on the analysis of the control task. Finally, we will attempt to integrate our approach in an overall framework of taxonomy for studying human actions in complex work context

  19. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant; Um modelo de manutencao centrada em confiabilidade aplicada ao sistema de agua de alimentacaco auxiliar de uma usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jefferson Borges

    1998-01-15

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  20. Auxiliary systems

    International Nuclear Information System (INIS)

    For a undisturbed reactor operation, the various Auxiliary and Ancillary Systems must function perfectly with the Reactor Coolant System together. While the Auxiliary Systems are directly connected to the Reactor Coolant System and therefore have contact with the Reactor Coolant, the Ancillary Systems perform tasks which do not directly influence reactor operation and in part are necessary exclusively for environment protection. The design criteria of the individual systems are a result of these tasks, especially in relation to availability, operational readiness and probability of failure. (orig.)

  1. Aging and service wear of auxiliary feedwater pumps for PWR nuclear power plants

    International Nuclear Information System (INIS)

    This paper describes investigations on auxiliary feedwater pumps being done under the Nuclear Plant Aging Research (NPAR) Program. Objectives of these studies are: to identify and evaluate practical, cost-effective methods for detecting, monitoring, and assessing the severity of time-dependent degradation (aging and service wear); recommend inspection and maintenance practices; establish acceptance criteria; and help facilitate use of the results. Emphasis is given to identifying and assessing methods for detecting failure in the incipient stage and to developing degradation trends to allow timely maintenance, repair or replacement actions. 3 refs

  2. Auxiliary systems

    International Nuclear Information System (INIS)

    Systems included under the heading ''Reactor Auxillary Systems'' are those immediately involved with the reactor operation. These include the systems for dosing and letdown of reactor coolant, as well as for the chemical dosing, purification and treatment of the reactor coolant and the cooling system in the controlled area. The ancillary systems are mainly responsible for liquid and gaseous treatment and the waste treatment for final storage. (orig.)

  3. CAREM-25. Auxiliary systems

    International Nuclear Information System (INIS)

    CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100 M Wt, about 25 M We). CAREM design is based on light water integrated reactor with slightly enriched uranium. In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented. Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor. (author)

  4. CAREM-25. Auxiliary systems

    International Nuclear Information System (INIS)

    CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100MWt, about 25MWe).CAREM design is based on light water integrated reactor with slightly enriched uranium.In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented.Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor

  5. Operation auxiliary system (SAO)

    International Nuclear Information System (INIS)

    This work presents an auxiliary system for nuclear power plants operation (SAO). The development purpose consisted in a computing supervision system to be installed at different sites of a reactor, mainly in the control room. The inclusion of this system to a nuclear power plant minimizes the possibility of human error for the facility operation. (Author)

  6. 核电厂辅助给水系统控制方案设计研究%Study on Control System of Auxiliary Feedwater System of Nuclear Power Plant

    Institute of Scientific and Technical Information of China (English)

    鲁超

    2015-01-01

    Auxiliary water supply system is an important system in the design of safety facilities of nuclear power station. The common cause fault of software and the power plant station blackout are two key factors for control system of ASG. So in the design of the control system, in order to deal with the two failure factors, the control strategy of diversity and emergency power supply are respectively adopted. Through analysis diversity control strategy is an effect method to prevent the failure of the safety functions resulting from software common cause failure which meets single failure criterion. In the case of station blackout, it is necessary to provide emergency power supply for control system of the starting ASG, and ensure the system safety functions workable.%辅助给水系统(ASG)是核电厂专设安全设施中重要的系统。对于实现对ASG功能控制的安全级系统,软件共因故障和全厂失电是导致控制失效的两个关键因素。因此,在进行控制系统设计时,为应对这两大失效因素,分别采用了多样性和增加应急电源的控制策略。通过分析,采用多样性控制策略可以有效地防止软件共因故障导致安全功能丧失的风险,保证系统满足单一故障的要求。同时在全厂断电的情况下,增加应急供电电源,对启动ASG功能的控制系统进行紧急供电,保证系统安全功能可执行。

  7. Microprocessor system for low power feedwater control

    International Nuclear Information System (INIS)

    The results of an ongoing Combustion Engineering development program to improve steam generator level control during low power operation are presented. A discussion is presented on the analytical tools, the verification process and the simulation capabilities that are currently available for the design and evaluation of advanced steam generator control systems. A review is then presented on the dynamic processes internal to the steam generator that must be controlled, the conceptual approach used in arriving at a design, followed by the verification of the design using a detailed digital simulation of the process and the control system. Finally, a discussion is presented on the reasons for the selection of a microprocessor based systems over a conventional analog system and the potential improvements in reliability and flexibility

  8. Loss of main and auxiliary feedwater event at the Davis-Besse Plant on June 9, 1985

    International Nuclear Information System (INIS)

    On June 9, 1985, Toledo Edison Company's Davis-Besse Nuclear Power Plant, located in Ottawa County, Ohio, experienced a partial loss of feedwater while the plant was operating at 90% power. Following a reactor trip, a loss of all feedwater occurred. The event involved a number of equipment malfunctions and extensive operator actions, including operator actions outside the control room. Several operator errors also occurred during the event. This report documents the findings of an NRC Team sent to Davis-Besse by the NRC Executive Director for Operations in conformance with the staff-proposed Incident Investigation Program

  9. Reliability improvement of a three-element feedwater control system for a pressurized water reactor

    International Nuclear Information System (INIS)

    A study of the three-element feedwater flow control system design from the perspective of qualitative Failure Modes and Effects Analysis and quantitative Fault Tree Analyses has been made. The study quantified the impact of reliability on valve control instrumentation system components and logic including electrical/electronic and pneumatic control components and valve operators. The study resulted in recommendations for modifications in the feedwater control system, which should improve its reliability and, therefore, increase unit availability through a reduction in hardware related control system malfunctions. These recommendations were ranked by their cost and their cost-benefit in order to facilitate utility management selection of those recommendations to be implemented

  10. Influence of feedwater and blowdown systems on the mineral distribution in WWER steam generators

    International Nuclear Information System (INIS)

    After modification of Dukovany NPP steam generator (SG) feedwater system, the increased concentration of minerals was measured in the cold leg of modified SG. Some modifications were performed on operating WWER 1000 steam generators with aim to optimize the water chemistry in the collectors area. Since the distribution of minerals can substantially affect on corrosion processes in steam generators, VITKOVICE, as a producer of WWER steam generators has focused the attention to the optimizing of these systems. To predict the mineral distribution on the secondary side of steam generators for considered feedwater/blowdown systems, the simple model of the flow distribution in the secondary side of SG was developed

  11. Influence of feedwater and blowdown systems on the mineral distribution in WWER steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Papp, L. [Inst. of Material Engineering, Ostrava (Switzerland)

    1995-12-31

    After modification of Dukovany NPP steam generator (SG) feedwater system, the increased concentration of minerals was measured in the cold leg of modified SG. Some modifications were performed on operating WWER 1000 steam generators with aim to optimize the water chemistry in the collectors area. Since the distribution of minerals can substantially affect on corrosion processes in steam generators, VITKOVICE, as a producer of WWER steam generators has focused the attention to the optimizing of these systems. To predict the mineral distribution on the secondary side of steam generators for considered feedwater/blowdown systems, the simple model of the flow distribution in the secondary side of SG was developed.

  12. The feedwater control system at a PWR. Examples from Ringhals 3

    International Nuclear Information System (INIS)

    GSE Power Systems AB sponsored by SKI has performed a comprehensive investigation of the feedwater control system at Ringhals 3. The assignment is based on signal analysis of measurement data recorded in the plant during operation. Well-known problems in connection to automatic control of feedwater flow in a PWR are also presented in the report outside the area of signal analysis. Some simple feedback systems are analysed and evaluated with the aid of simulation in the introduction of the report. These simulated systems are a good background to understand the actual automatic control systems at Ringhals 3. Typical problems with feedwater control in foreign plants are: Non minimum phase for the water level dynamics in the steam exchanger, windup of the controller with integrating function, hysteresis, backlash or other types of non-linearities in the feedwater valve that can result in limit cycle oscillations and the method with feed forward to reduce the influence of disturbances via the steam flow. These types of problems are demonstrated with simulation and possible ways to reduce the influence are discussed in the report. The automatic control of feedwater flow is performed with three different control systems with different aims at Ringhals 3. The first system controls the feedwater valve with the aim to maintain agreement between the water reference value and water level in each steam generator. This system is called the water level controller. The second system controls the speed of the feedwater pumps with the aim to maintain 8 bar differential pressure over the feedwater valve for the valve out of three with lowest pressure drop. This is called the DP-control system. The third system compensates the speed of the feedwater pumps with the aim to eliminate difference in condenser levels between the two turbines. This is called condenser control system. The results prove that the DP-control acts fastest with a time constant equal 13 seconds. The step tests

  13. Impact of Feedwater Salinity on Energy Requirements of a Small-Scale Membrane Filtration System

    OpenAIRE

    Richards, Bryce S.; Masson, L; Schaefer, Andrea

    2009-01-01

    Many remote communities in both developed and developing countries lack electricity and clean drinking water. One solution, for such communities that rely on brackish groundwater, is a photovoltaic (PV) powered hybrid ultrafiltration (UF) / nanofiltration (NF) or reverse osmosis (RO) membrane filtration system. The system prototype described here can produce between 150 – 280 litres of clean water for each peak sunshine hour, depending on the salinity of the feedwater (1 – 5 g/...

  14. Modeling a high output marine steam generator feedwater control system which uses parallel turbine-driven feed pumps

    Institute of Scientific and Technical Information of China (English)

    QIU Zhi-qiang; ZOU Hai; SUN Jian-hua

    2008-01-01

    Parallel turbine-driven feedwater pumps are needed when ships travel at high speed. In order to study marine steam generator feedwater control systems which use parallel turbine-driven feed pumps,a mathematical model of marine steam generator feedwater control system was developed which includes mathematical models of two steam generators and parallel turbine-driven feed pumps as well as mathematical models of feedwater pipes and feed regulating valves. The operating condition points of the parallel turbine-driven feed pumps were calculated by the Chebyshev curve fit method. A water level controller for the steam generator and a rotary speed controller for the turbine-driven feed pumps were also included in the model. The accuracy of the mathematical models and their controllers was verified by comparing their results with those from a simulator.

  15. Development of superconducting high gradient magnetic separation system for scale removal from feed-water in thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Shibatani, Saori; Nakanishi, Motohiro; Mizuno, Nobumi [Osaka University, Osaka (Japan); and others

    2016-03-15

    A Superconducting High Gradient Magnetic Separation (HGMS) system is proposed for treatment of feed-water in thermal power plant. This is a method to remove the iron scale from feed-water utilizing magnetic force. One of the issues for practical use of HGMS system is to extend continuous operation period. In this study, we designed the magnetic filters by particle trajectory simulation and HGMS experiments in order to solve this problem. As a result, the quantity of magnetite captured by each filter was equalized and filter blockage was prevented. A design method of the magnetic filter was proposed which is suitable for the long-term continuous scale removal in the feed-water system of the thermal power plant.

  16. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system

    International Nuclear Information System (INIS)

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  17. Vibration monitoring in Angra I nuclear power plant steam generator feedwater system

    International Nuclear Information System (INIS)

    The safety and reliability are the primary criteria in the design and operation of a nuclear power plant. However, due to the aging of the plant and its components, it is difficult to assure that what was originally built and qualified under strict standards is still guaranteed. In order to assure safety, reliability, availability and capacity, aging management through predictive maintenance techniques are being introduced in most plants around the world. In this present work, the monitoring of the vibrations signatures at the Angra I nuclear power plant steam generators feedwater systems main components such as the main feedwater pumps, pressure breaker blocks and the by pass valves, is presented. The vibration data was acquired, afterwards some major repairs were performed and during the startup commissioning procedures. Some of the major repairs performed are: changing of one pump shaft with balancing and alignment, replacement of the original bypass control valves by new disk stack type pneumatic control valves. The results show that no major vibrations anomaly is present after the maintenance indicating adequacy of the repairs made. The monitoring of the vibration in nuclear power plant components is being increasingly used as a tool for predictive maintenance. (author)

  18. The German and English Auxiliary Systems and Complex Predicates

    Science.gov (United States)

    McCormick, Terrence C.

    1976-01-01

    This paper explores the auxiliary systems of English and German and the use of the auxiliary verbs in various complex predicate structures in the two languages. It aims at alleviating two types of problems in learning German involving governing patterns and ordering problems in clauses. (CHK)

  19. Auxiliary DCP data acquisition system. [airborne system

    Science.gov (United States)

    Snyder, R. V.

    1975-01-01

    An airborne DCP Data Aquisition System has been designed to augment the ERTS satellite data recovery system. The DCP's are data collection platforms located at pertinent sites. With the appropriate sensors they are able to collect, digitally encode and transmit environmental parameters to the ERTS satellite. The satellite in turn relays these transmissions to a ground station for processing. The satellite is available for such relay duty a minimum of two times in a 24-hour period. The equipment is to obtain continuous DCP data during periods of unusual environmental activity--storms, floods, etc. Two circumstances contributed to the decision to design such a system; (1) Wallops Station utilizes surveillance aircraft in support of rocket launches and also in support of earth resources activities; (2) the area in which Wallops is located, the Delaware and Chesapeake Bay areas, are fertile areas for DCP usage. Therefore, by developing an airborne DCP receiving station and installing it on aircraft more continuous DCP data can be provided from sites in the surrounding areas at relatively low cost.

  20. Modeling and simulation of the feedwater system, associated controller and interface with the user for the SUN-RAH nucleo electric plants university student simulator

    International Nuclear Information System (INIS)

    The simulation process of the component systems of the feedwater of a nucleo electric plant is presented, using several models of reduced order that represent the diverse elements that compose the systems like: the heaters of feedwater, the condenser, the feedwater pump, etc. The integration of the same ones in one simulative structure, and the development of a platform that to give the appearance of to be executed in continuous time, it is the objective of the feedwater simulator, as well as of the SUN-RAH simulator, of which is part. The simulator uses models of reduced order that respond to the observed behavior of a nuclear plant of BWR type. Likewise, it is presented a model of a flow controller of feedwater that will be the one in charge of regulating the demand of the system according to the characteristics and criticize restrictions of safety and controllability, assigned according to those wanted parameters of performance of this system inside the nucleo electric plant. The integration of these models, the adaptation of the variables and parameters, are presented in a way that the integration with the other ones models of the remaining systems of the plant (reactor, steam lines, turbine, etc.), be direct and coherent with the principles of thermodynamic cycles relative to this type of generation plants. The design of those graphic interfaces and the environment where the simulator works its are part of those developments of this work. The reaches and objectives of the simulator complement the description of the simulator. (Author)

  1. Radio frequency auxiliary heating systems design in ITER

    International Nuclear Information System (INIS)

    A combination of radio frequency (RF) auxiliary heating systems will provide at least one half of the required 100 MW of auxiliary power in ITER. Five of the 20 equatorial ports are assigned to RF heating systems. Recent work has focused on developing an integrated equatorial port-plug design concept for all of the RF auxiliary heating systems as well as other equatorial port systems such as diagnostics. Common features of the design approach include the use of identical interfaces to services such as cooling water, vacuum, mechanical connection to the vessel, and maintenance. Based on the integrated port concept, a high level of design integration has been achieved for the RF heating systems. Implementation of the integrated design concept has been accomplished without significantly affecting the individual system performance and with limited impact on the torus layout. (author)

  2. Application of the RCM (Reliability Centered Maintenance) approach to the optimization of emergency feedwater pump system maintenance

    International Nuclear Information System (INIS)

    The major steps of the RCM analysis for the emergency feedwater pump system at the Dukovany NPP were as follows: Familiarization with the Dukovany maintenance process and strategy; Collection of information regarding data and information availability; system selection for the RCM study; implementation and use of suitable software; consulting the staff; FFA (Functional Failure Analysis) and FMEA (Failure Mode and Effect Analysis); Assessment of current periodical maintenance; and recommendations from the RCM analysis. The following Annexes are appended: A - Technological layouts; B - List of components; C - Information on functions; D - Critical components; E - FMEA; F - Consulting the staff (notes); G - Failure data (from RCM Workstation); H - Current periodical maintenance tasks; I - Selection of periodical maintenance tasks. (P.A.)

  3. Performance of a small solar-powered hybrid membrane system for remote communities under varying feedwater salinities

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A.I.; Remy, C. [University of Wollongong, NSW (Australia). Environmental Engineering; Richards, B.S. [University of New South Wales, Sydney (Australia). Centre of Excellence for Advanced Silicon Photovoltaics and Photonics

    2005-07-01

    An estimated 1 billion people are living both without access to clean drinking water or electricity. The small photovoltaic (PV)-powered hybrid membrane system described here is designed to address the plight of some of these people. PV and membrane technologies are chosen due to suitability for operation in remote and often harsh conditions. An ultrafiltration (UF) pre-treatment is included to remove bacteria and most pathogens, while a reverse osmosis (RO) or nanofiltration (NF) membrane desalinates the brackish feedwater. Several parameters were examined in order to optimise the system performance, including (i) feed salt concentration, (ii) operating pressure, (iii) system recovery, (iv) specific energy consumption (SEC, kWh/m{sup 3}), and (v) salt retention. In addition, experiments were performed over a whole day to determine system performance under varying levels of solar radiation. The minimum SEC (relatively high due to the current single-pass mode of operation) varies from 5.5 kWh/m{sup 3} at a feed concentration of 1 g/L salt to 26 kWh/m{sup 3} at a feed concentration of 7.5 g/L salt, which is the upper limit of the system in terms of salt concentration. (author)

  4. Feedwater heater workshop proceedings

    International Nuclear Information System (INIS)

    The March 13-14, 1979 EPRI sponsored workshop on design, operation and maintenance problems with nuclear feedwater heaters identified a large number of significant technical areas of concern. The reported problems relate to nearly all facets of feedwater heater technology. In particular, hydrometallurgical problems such as stress corrosion of stainless tubing, erosion/corrosion wear of tube-tubesheet joints, and flashing related tube erosion at the entrance to the drain cooler region were reviewed in depth. Shortcomings in current design standards and design specifications were also discussed. Solutions to specific technical problems such as mechanics of flow induced vibration failures, improved synthesis of feedwater heater orientation with plant layout, and drain outlet piping design were presented. A list of important technical problems requiring additional research and development for improved design guidelines was developed. The proceedings contain all edited material of archival quality developed in this workshop

  5. Assembly auxiliary system for narrow cabins of spacecraft

    Science.gov (United States)

    Liu, Yi; Li, Shiqi; Wang, Junfeng

    2015-09-01

    Due to the narrow space and complex structure of spacecraft cabin, the existing asssembly systems can not well suit for the assembly process of cabin products. This paper aims to introduce an assembly auxiliary system for cabin products. A hierarchical-classification method is proposed to re-adjust the initial assembly relationship of cabin into a new hierarchical structure for efficient assembly planning. An improved ant colony algorithm based on three assembly principles is established for searching a optimizational assembly sequence of cabin parts. A mixed reality assembly environment is constructed with enhanced information to promote interaction efficiency of assembly training and guidance. Based on the machine vision technology, the inspection of left redundant objects and measurement of parts distance in inner cabin are efficiently performed. The proposed system has been applied to the assembly work of a spacecraft cabin with 107 parts, which includes cabin assembly planning, assembly training and assembly quality inspection. The application result indicates that the proposed system can be an effective assistant tool to cabin assembly works and provide an intuitive and real assembly experience for workers. This paper presents an assembly auxiliary system for spacecraft cabin products, which can provide technical support to the spacecraft cabin assembly industry.

  6. Interaction region design and auxiliary detector systems for an EIC

    Directory of Open Access Journals (Sweden)

    Petti R.

    2016-01-01

    Full Text Available There are a number of exciting physics opportunities at a future electron-ion collider facility. One possible design for such a facility is eRHIC, where the current RHIC facility located at Brookhaven National Lab would be transformed into an electron-ion collider. It is imperative for a seamless integration of auxiliary detector systems into the interaction region design to have a machine that meets the needs for the planned physics analyses, as well as take into account the space constraints due to the tunnel geometry and the necessary beam line elements. In this talk, we describe the current ideas for integrating a luminosity detector, electron polarimeter, roman pots, and a low Q2-tagger into the interaction region for eRHIC.

  7. Auxiliary signal processing system for a multiparameter radar

    Science.gov (United States)

    Chandrasekar, V.; Gray, G. R.; Caylor, I. J.

    1993-01-01

    The design of an auxiliary signal processor for a multiparameter radar is described with emphasis on low cost, quick development, and minimum disruption of radar operations. The processor is based around a low-cost digital signal processor card and personal computer controller. With the use of such a concept, an auxiliary processor was implemented for the NCAR CP-2 radar during a 1991 summer field campaign and allowed measurement of additional polarimetric parameters, namely, the differential phase and the copolar cross correlation. Sample data are presented from both the auxiliary and existing radar signal processors.

  8. Process Modeling and Simulation of Feedwater Heaters Drains and Vents System of PFBR

    Directory of Open Access Journals (Sweden)

    T.Lakshmi Priyanka

    2013-10-01

    Full Text Available Nuclear Power Plants are a complex system and need to be controlled very meticulously to avoid any catastrophe from occurring. The safety and availability of the power plant relies on the human operators both through their ability and reliability to ensure smooth and trouble-free plant operations. Training the operators on normal plant operation, maintenance, fault diagnosis and unforeseen emergencies in the plant helps reduce the latency period of the plant and thus increase the efficiency. Operator Training Simulator has become an indispensable entity in imparting hands on training to these operators. Development of process simulators calls for the process to be designed, modeled and implemented to replicate the real plant in steady state and transient conditions.

  9. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system; Modernizacion del control de nivel de los calentadores de agua de alimentacion de C.N. Almaraz I mediante el sistema OVATION

    Energy Technology Data Exchange (ETDEWEB)

    Madronal Rodriguez, E.; Cabrero Munoz, J. E.

    2010-07-01

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  10. Indigenous manufacturing realization of twin source and its auxiliary system

    International Nuclear Information System (INIS)

    operation) as well as Vacuum mode (DNB type vacuum immersed operation). The Twin Source shall be manufactured as per ASME guidelines for pressure vessel. Experiments on the Twin Source are foreseen in the near future, as all the auxiliary systems like 180 kW, RF generator system, vacuum vessel with Pumping station, Cooling water system, Data acquisition and control system (DACS) and other power supply systems are already installed in the lab premises. The paper discusses the FEA based engineering design, simplified manufacturing design, manufacturing experience with highlighting quality control and the system integration activities undertaken for the TWIN source test facility. (author)

  11. Low-cost auxiliary system for broadband NMR on strongly magnetic systems

    DEFF Research Database (Denmark)

    Nevald, Rolf; Hansen, Poul Erik

    1978-01-01

    A low cost auxiliary system consisting of He cryostat, superconducting magnet, and sample holder assembly with field probe has been constructed. The system meets the requirements of NMR on strongly paramagnetic or ordered magnetic materials, which are accurate temperature settings over a wide range...

  12. Feedwater control device for a reactor

    International Nuclear Information System (INIS)

    Purpose: To eliminate the water level deviation due to the recycling flowrate, as well as enable a stable control to a reference value even upon changes in the recycling flowrate caused by the variation in the opening degree of a minimum flow valve. Constitution: Reactor recycling system comprises a feedwater pump, a flowrate control valve, a reactor water level detector, and a minimum flow line and a minimum flow valve for preventing the overheating of the feedwater pump at a low flowrate. A flowrate compensator is further disposed, in which a recycling flowrate signal is subtracted from a pump flow rate signal and the result is fedback as a compensated pump flowrate signal. This enables the control system to operate at a rapid response for suppressing the effect of the recycling flowrate as external disturbance, whereby the water level in the reactor can be controlled stably to the reference level and the possibility deviating from an allowable range is decreased significantly. (Kamimura, M.)

  13. The dynamic responses of the soil-auxiliary buildings structure interaction system

    International Nuclear Information System (INIS)

    The dynamic responses of the soil-auxiliary buildings structure interaction system in the nuclear power plant are concerned. The main distinguished feature of this study is that the extreme un-symmetry of the auxiliary buildings and reactor containment are considered. A Synthetical mechanical model for study is established. Finally, the analysis of the dynamic response of the Qinshan Nuclear Power Plant structure is taken as a simple example of applying this method and the numerical results are given

  14. Containment vessel, its auxiliary system and plant air conditioning system of advanced thermal reactor Fugen

    International Nuclear Information System (INIS)

    The functional requirement for, the design and the construction of, and the functional test on the containment vessel, its auxiliary system, the plant air conditioning and ventilation system of the advanced thermal reactor, Fugen, are described in detail. The main specifications of the containment vessel are as follows: The type enclosed cylinder, the maximum operating pressure 1.35 kg/cm2g, the maximum operating temperature 100 deg C, the leak rate 0.4%/day, the inner diameter 36 m. The height 64 m, the volume 40,900 m3, and the material JIS G3118, SGV-49. The containment vessel is provided with an hatch of 5 m diameter for carrying equipments in two air locks, many high and low voltage cable penetrations, pipe penetrations, a transfer shoot and isolation values. The functions and the specifications of the containment vessel and its auxiliary equipments are explained. The relating auxiliary systems are composed of the containment vessel spray system, the pool facility for steam blow-down, the recirculation system for the air in the vessel, the annulus evacuation system and its pressure control devices, the pressure measuring instruments and pressure relief valves and the temperature measuring devices for the containment vessel, and the object, function, layout and installation of these systems are explained. Concerning the air conditioning system, each main building has the special subsystem, and they are introduced. The progress stage of construction works and the procedure and results of the functional test at the site are described. (Nakai, Y.)

  15. Aiming of Kirkpatrick-Baez microscope based on auxiliary optical system

    International Nuclear Information System (INIS)

    An auxiliary optical system has been designed, which can provide precise positioning for aiming Kirkpatrick-Baez (KB) microscope object location. An 8 keV X-ray imaging system by KB microscope with periodic multilayer films has been designed. The field of view and depth of field in the resolution of 5 μm are got, and then the corresponding point and depth of field in diagnostic experiments are calculated. Based on the object-image relations and precision of the KB microscope, an auxiliary visible light imaging system is designed and X-ray imaging experiments are performed, which can achieve equivalent aiming between the visible imaging system and the KB microscope. The results show that ±20 μm vertical axis plane and ±300 μm axial accuracy are achieved through the auxiliary optical path, which can meet the object point positioning requirements of the KB microscope. (authors)

  16. Dynamic modelling and response characteristics of a magnetic bearing rotor system including auxiliary bearings

    Science.gov (United States)

    Free, April M.; Flowers, George T.; Trent, Victor S.

    1993-01-01

    Auxiliary bearings are a critical feature of any magnetic bearing system. They protect the soft iron core of the magnetic bearing during an overload or failure. An auxiliary bearing typically consists of a rolling element bearing or bushing with a clearance gap between the rotor and the inner race of the support. The dynamics of such systems can be quite complex. It is desired to develop a rotor-dynamic model and assess the dynamic behavior of a magnetic bearing rotor system which includes the effects of auxiliary bearings. Of particular interest is the effects of introducing sideloading into such a system during failure of the magnetic bearing. A model is developed from an experimental test facility and a number of simulation studies are performed. These results are presented and discussed.

  17. [Analysis on prescription rules of treating senile dementia based on traditional Chinese medicine inheritance auxiliary systems].

    Science.gov (United States)

    Zong, Xin; Ji, Xu-Ming; Wei, Feng-Qin; Shi, Zuo-Rong

    2014-02-01

    This is designed to analyze and summarize medication rules for treating senile dementia with Chinese medicine in CNKI according to the traditional Chinese medicine (TCM) inheritance auxiliary system. Collect documents in CNKI that account treating senile dementia with Chinese formula; filter and establish a formula database, and then to search for medication rules on the TCM inheritance auxiliary system. It is filtered that 104 formulas are used for treating senile dementia screening treat senile dementia, involving 147 kinds of Chinese medicine. Tonic medicine are most frequently used, followed by the medicine of activating blood circulation and resuscitating; medicine pair most used is Ligusticum chuanxiong Hort-Acorus tatarinowii, accounting for 27.9% of all formula. And then 8 core pairs and 4 new formulas are evolved. Analysis on formulas for treating senile dementia filtered form CNKI by TCM inheritance auxiliary system shows prescription is mainly tonifying, activating blood circulation and resuscitating, that reveals prescription rules, to provide a reference for clinical treatment.

  18. Dynamic modelling and response characteristics of a magnetic bearing rotor system with auxiliary bearings

    Science.gov (United States)

    Free, April M.; Flowers, George T.; Trent, Victor S.

    1995-01-01

    Auxiliary bearings are a critical feature of any magnetic bearing system. They protect the soft iron core of the magnetic bearing during an overload or failure. An auxiliary bearing typically consists of a rolling element bearing or bushing with a clearance gap between the rotor and the inner race of the support. The dynamics of such systems can be quite complex. It is desired to develop a rotordynamic model which describes the dynamic behavior of a flexible rotor system with magnetic bearings including auxiliary bearings. The model is based upon an experimental test facility. Some simulation studies are presented to illustrate the behavior of the model. In particular, the effects of introducing sideloading from the magnetic bearing when one coil fails is studied.

  19. Computer determination of event maps with application to auxiliary supply systems

    International Nuclear Information System (INIS)

    A method of evaluating the reliability of sequential operations in systems containing standby and alternate supply facilities is presented. The method is based upon the use of a digital computer for automatic development of event maps. The technique is illustrated by application to a nuclear power plant auxiliary supply system. (author)

  20. Performance of turbine auxiliaries and service systems at Rajasthan Atomic Power Station

    International Nuclear Information System (INIS)

    Performance of the turbine auxiliaries and service systems at the Rajasthan Atomic Power Station, India are described. Some of the specific problems encountered in connection with the feed water, turbine governing and common services like compressed air, chilled water, water treatment and chlorination systems are outlined. (K.B.)

  1. Pressurized water-reactor feedwater piping response to water hammer

    International Nuclear Information System (INIS)

    The nuclear power industry is interested in steam-generator water hammer because it has damaged the piping and components at pressurized water reactors (PWRs). Water hammer arises when rapid steam condensation in the steam-generator feedwater inlet of a PWR causes depressurization, water-slug acceleration, and slug impact at the nearest pipe elbow. The resulting pressure pulse causes the pipe system to shake, sometimes violently. The objective of this study is to evaluate the potential structural effects of steam-generator water hammer on feedwater piping. This was accomplished by finite-element computation of the response of two sections of a typical feedwater pipe system to four representative water-hammer pulses. All four pulses produced high shear and bending stresses in both sections of pipe. Maximum calculated pipe stresses varied because the sections had different characteristics and were sensitive to boundary-condition modeling

  2. Evaluation of thermal striping for the plugging system in the secondary auxiliary cooling system in JOYO

    Energy Technology Data Exchange (ETDEWEB)

    Isozaki, Kazunori; Ogawa, Tooru; Kubo, Atsuhiko; Aoki, Hiroshi; Ozawa, Kenji [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center; Sugaya, Kazushi

    1998-05-01

    Scrutiny based on the convenient evaluation to verify whether we have the place where thermal striping in the pipe confluence part was thought to be a primary factor for the heavy accident or not has been done in JOYO. As the result, the big temperature difference ({Delta}Tin) existed at the inner pipe confluence part of the plugging system in the secondary main and auxiliary cooling system. Therefore, detailed evaluation of thermal striping was needed. With the thermocouples of high response installed, the temperature fluctuation in outer surface of the pipe was measured on the secondary auxiliary plugging system for the reason why the temperature difference ({Delta}Tin) was the biggest. And, the temperature fluctuation in inner surface of the pipe and stress occurring in the pipe plate thickness direction was evaluated by means of non-linear structure analysis system FINAS`. The above-mentioned evaluation results were as follows. (1) The maximum temperature fluctuation occurring in the pipe was always located from the center of inner pipe confluence to 10 mm position of the down-stream side. (2) The maximum temperature fluctuation range was about 33degC in outer surface of the pipe. And, controlling frequency of the temperature fluctuation was 0.04 Hz and 0.09 Hz. (3) Time delay was almost never contained in the temperature fluctuation elements between inner and outer surface of the pipe. And, the big temperature distribution did not occur in the pipe plate thickness direction was confirmed that the big temperature distribution did not occur in the pipe plate thickness direction. The temperature fluctuation range in the pipe inner surface was almost the same as that of the pipe outer surface. It was confirmed that the stress occurring there was enough lowered than the design fatigue limit of SUS304 which was the materials in the confluence part of the plugging system inner part in the secondary main and auxiliary cooling system. (J.P.N.)

  3. Replacement of the feedwater pipe system in reactor building outside containment at the nuclear power plant Philippsburg; Austausch der Speisewasserleitung im Reaktorgebaeude ausserhalb SHB im Kernkraftwerk Philippsburg I

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, A. [Energie-Versorgung Schwaben AG, Stuttgart (Germany); Labes, M. [Siemens AG Unternehmensbereich KWU, Offenbach am Main (Germany); Schwenk, B. [Kernkraftwerk Philippsburg GmbH (Germany)

    1998-11-01

    After full replacement of the feedwater pipe system during the inspection period in 1997, combined with a modern materials, manufacturing and analysis concept, the entire pipe system of the water/steam cycle in the reactor building of KKP 1 now consists of high-toughness materials. The safety level of the entire plant has been increased by leaving aside postulation of F2 breaks in the reactor building and providing for protection against 0.1 leaks. Based on fluid-dynamic calculations for the cases of pump failure and pipe break, as well as pipe system calculations in 5 extensive calculation cycles, about 130 documents were filed for inspection and approval (excluding preliminary test documents on restraints). Points of main interest for safety analysis in this context were the optimised closing performance of the 3rd check valves and the integrity of the nozzle region at the RPV. (oirg./CB) [Deutsch] Durch den Restaustausch der Speisewasserleitungen in der Revision 1997, verbunden mit einem modernen Werkstoff-, Fertigungs- und Nachweiskonzept, sind im Reaktorgebaeude von KKP 1 in den Hauptleitungen des Wasser-Dampf-Kreislaufes nur noch hochzaehe Werkstoffe eingesetzt. Durch den Verzicht auf das Postulat von 2F-Bruechen im Reaktorgebaeude und durch die Auslegung gegen 0,1F-Lecks wird das Sicherheitsniveau der Anlage insgesamt gesteigert. Ausgehend von fluiddynamischen Berechnungen fuer Pumpenausfall und Rohrbruch sowie Rohrsystem-Berechnungen in 5 umfangreichen Berechnungskreisen wurden fuer die Genehmigung und Begutachtung ca. 130 Unterlagen (ohne Halterungs-Vorpruefunterlagen) eingereicht und vom Gutachter geprueft. Schwerpunkte der Nachweisfuehrung waren die Optimierung des Schliessverhaltens der 3. Rueckschlagarmaturen sowie der Integritaetsnachweis des RDB-Anschlusses. (orig./MM)

  4. Application of Sm0/Auxiliary and Sm0/MCln System in Organic Synthesis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong-Min; LIU Yun-Kuia

    2001-01-01

    @@Though samarium metal itself has strong reducingpower, in most cases, certain additives are still needed when it is used as a reductant because the surface of samarium metal is inactive.Thus Sm0/auxiliary systems are proposed.The explored systems include: Sm0/I2,Sm0/TMSCl, Sm0/THF-NH4Cl (aq.), Sm0/Cp2TiCl2,Sm(Hg), Sm0/cat.KI etc.

  5. Modelling a feed-water control system of a steam generator in the framework of the dynamic reliability

    OpenAIRE

    Babykina, Génia; Brinzei, Nicolae; Aubry, Jean-François; Deleuze, Gilles

    2013-01-01

    The paper deals with the exploration of an industrial complex system behaviour and its probabilistic safety assessment (PSA). The main purposes are to build a model which realistically represents the system structure, to carry out the Monte Carlo study of the system behaviour and to perform the analysis of system reliability. The complexity of the system consists in its structure, size, dynamic operational behaviour, complex interactions between the system and its environment, etc. The theore...

  6. [Participation of dental auxiliary personnel in local health systems].

    Science.gov (United States)

    Frazão, P; Castellanos, R A

    1999-02-01

    Though numerous local health systems (sistemas locales de salud, or SILOS) in Brazil employ dental assistants, there is little information on the contributions these workers make to oral health programs. The purpose of this study was to examine the role of such workers in 10 SILOS in five municipalities in the state of São Paulo. Of the 325 dental assistants and dental hygienists employed in those systems, 245 (75.4%) answered a questionnaire that had been prepared. The results showed variations in the degree to which dental assistants participated in oral health promotion activities in the SILOS studied. In some SILOS, these workers devoted more time to dental health promotion activities than to helping perform dental tasks with individual patients. The most frequent oral health promotion activities were fluoride rinses, plaque detection followed by supervised brushing, and educational activities at basic health units and schools. In all cases, dental assistants working in the SILOS played a significant role in helping transform the practice of dentistry within the sphere of public health.

  7. Modeling and simulation of the feedwater system, associated controller and interface with the user for the SUN-RAH nucleo electric plants university student simulator; Modelado y simulacion del sistema de agua de alimentacion, controlador asociado e interfaz con el usuario para el simulador universitario de nucleoelectricas SUN-RAH

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez B, A. [Laboratorio de Analisis de Ingenieria de Reactores Nucleares, DEPFI Campus Morelos, en IMTA Jiutepec, Morelos (Mexico)]. e-mail: alitet@eresmas.com

    2003-07-01

    The simulation process of the component systems of the feedwater of a nucleo electric plant is presented, using several models of reduced order that represent the diverse elements that compose the systems like: the heaters of feedwater, the condenser, the feedwater pump, etc. The integration of the same ones in one simulative structure, and the development of a platform that to give the appearance of to be executed in continuous time, it is the objective of the feedwater simulator, as well as of the SUN-RAH simulator, of which is part. The simulator uses models of reduced order that respond to the observed behavior of a nuclear plant of BWR type. Likewise, it is presented a model of a flow controller of feedwater that will be the one in charge of regulating the demand of the system according to the characteristics and criticize restrictions of safety and controllability, assigned according to those wanted parameters of performance of this system inside the nucleo electric plant. The integration of these models, the adaptation of the variables and parameters, are presented in a way that the integration with the other ones models of the remaining systems of the plant (reactor, steam lines, turbine, etc.), be direct and coherent with the principles of thermodynamic cycles relative to this type of generation plants. The design of those graphic interfaces and the environment where the simulator works its are part of those developments of this work. The reaches and objectives of the simulator complement the description of the simulator. (Author)

  8. Comparative LCA of methanol-fuelled SOFCs as auxiliary power systems on-board ships

    Energy Technology Data Exchange (ETDEWEB)

    Strazza, C.; Del Borghi, A.; Costamagna, P. [Department of Chemical and Process Engineering ' ' G.B. Bonino' ' (DICheP), University of Genoa, Via all' Opera Pia 15, 16145 Genova (Italy); Traverso, A.; Santin, M. [Department of Machines, Energetic Systems and Transport (DIMSET), University of Genoa, Via all' Opera Pia 15, 16145 Genova (Italy)

    2010-05-15

    Fuel cells own the potential for significant environmental improvements both in terms of air quality and climate protection. Through the use of renewable primary energies, local pollutant and greenhouse gas emissions can be significantly minimized over the full life cycle of the electricity generation process, so that marine industry accounts renewable energy as its future energy source. The aim of this paper is to evaluate the use of methanol in Solid Oxide Fuel Cells (SOFC), as auxiliary power systems for commercial vessels, through Life Cycle Assessment (LCA). The LCA methodology allows the assessment of the potential environmental impact along the whole life cycle of the process. The unit considered is a 20 kWel fuel cell system. In a first part of the study different fuel options have been compared (methanol, bio-methanol, natural gas, hydrogen from cracking, electrolysis and reforming), then the operation of the cell fed with methanol has been compared with the traditional auxiliary power system, i.e. a diesel engine. The environmental benefits of the use of fuel cells have been assessed considering different impact categories. The results of the analysis show that fuel production phase has a strong influence on the life cycle impacts and highlight that feeding with bio-methanol represents a highly attractive solution from a life cycle point of view. The comparison with the conventional auxiliary power system shows extremely lower impacts for SOFCs. (author)

  9. Energy simulation of solar assisted absorption system and examination of clearness index effects on auxiliary heating

    International Nuclear Information System (INIS)

    The smog and pollutants in the atmospheric air of heavily populated urban areas are anticipated to have substantial adverse effects on the collection of solar energy and the performance of solar energy systems. The objectives of this study are (a) to develop a simulation model for analyzing the performance of a water-LiBr solar assisted absorption system with an auxiliary heating source and (b) to examine the effects of clearness index on the auxiliary heating requirements. To achieve the objectives, a numerical model for a water-LiBr solar assisted absorption system is developed, and the influence of a reduction in the clearness index, based on actual recorded data, is investigated for constant and time varying cooling loads. Under the condition of peak solar gain on July 21, when a 1000 m2 solar collector is designed to provide 70% of the heating energy required for a constant cooling load of 1265 MJ/h (=100 refrigeration tons), as the system coefficient of performance decreases due to higher ambient temperatures, it is found that a reduction in the clearness index from 0.63 to 0.52 results in a 67% increase in auxiliary heating required of the boiler. It is concluded that accounting for clearness index data is necessary for accurate prediction of solar energy collection

  10. Simulation Research on Passive Auxiliary Feedwater System for NPP%核电站非能动辅助给水系统仿真研究

    Institute of Scientific and Technical Information of China (English)

    师二兵; 方成跃; 王畅; 赵观辉

    2016-01-01

    以先进核电站AP1000为研究对象,在其蒸汽发生器二次侧设计了1套耗汽驱动汽动辅助给水泵的非能动辅助给水系统.使用RELAP5程序计算分析全厂断电事故下设计系统的运行特性,研究其应对事故工况的能力.计算结果表明:全厂断电事故下,设计的非能动辅助给水系统可有效地排出堆芯余热,保证反应堆的安全;由于冷却剂体积收缩,170 min时稳压器排空;该系统可连续运行200 min,排出事故后的大部分堆芯余热.非能动辅助给水系统可作为全厂断电事故后的应急缓解方案.

  11. Development of a New Condensation Heat Transfer Model for the Nearly Horizontal Tube of the APR+ PAFS (Passive Auxiliary Feed-water System)

    International Nuclear Information System (INIS)

    Korea Atomic Energy Research Institute (KAERI) has recently conducted PASCAL experiment to confirm the performance of PAFS. From the work, it is founded that the condensation heat transfer coefficient predicted by best estimated safety analysis code MARS (Multi-dimensional Analysis of Reactor Safety) was underestimated compared to the experimental data. Shah correlation embedded in MARS code is the typical model using the empirical two-phase multiplier to determine condensation heat transfer coefficient for annular flow in the condensing tube. On the other hand, the PASCAL experiment indicated that a stratified-wavy flow generally tends to occur in the downward inclined tube of the condensation heat exchanger. Therefore, in order to improve the prediction capability of safety analysis codes for PAFS, the present study has proposed a new condensation heat transfer model package for the nearly horizontal tube, which determines mechanistically the local heat transfer coefficient based on the flow regimes. To enhance prediction capability of one-dimensional best estimated code MARS for the PAFS of the Korean 3.5 generation nuclear power plant APR+, a new condensation heat transfer model package has been developed. The model package consists of the one-dimensional separated model for the void fraction, a flow regime model based on wetted angle, and the condensation heat transfer correlations. The model package considers the inclination angle of the condensing tube and various flow regimes that are expected in the tube during condensation process

  12. Computer-generated direct perception displays for supporting PWR feedwater system start-up and fault management: a proof-of-principle in design

    International Nuclear Information System (INIS)

    difficult problems which have not yet been investigated in extending the proposed approach to fault management. In the present research Rasmussen et al's framework was used for designing computer-generated graphical displays that support pressurized water reactor (PWR) start-up. Specifically, a suite of displays was developed to support a PWR's feedwater (FW) system start-up as a proof-of-principle. The suite of displays demonstrate the theoretical design approach and are not meant to represent a fully implementable interface for FW system control. (author)

  13. Use of Reliability-Centered Maintenance for the McGuire nuclear station feedwater system. Final report

    International Nuclear Information System (INIS)

    An earlier prototype application of Reliability-Centered Maintenance (RCM) to the Component Cooling Water System at Florida Power and Light's Turkey Point Plant demonstrated that the RCM methodology is applicable for developing or revising Preventive Maintenance (PM) programs in operating nuclear power plants. This report discusses an additional RCM application made to the Main Feed Water System at Duke Power Company's McGuire Nuclear Station. The study was conducted in order to demonstrate more fully all aspects of the RCM approach. The report reviews the RCM methodology and details its application to the Main Feed Water System. The resulting RCM-based PM program is briefly compared to the current PM program for the system. The RCM process suggested four current PM tasks as candidates for Condition Directed (CD) consideration or revision and two current CD tasks as candidates for expanded scope. The RCM-based program also added nine new CD tasks as candidates to improve the effectiveness of the PM program and two new Failure Finding tasks as candidates to avoid startup delays. The report also discusses the lessons learned through the two studies. The study shows the RCM methodology to be an effective tool both for defining a PM program and for providing traceable documentation to enhance the credibility of the PM program

  14. Performance of a small solar-powered hybrid membrane system for remote communities under varying feedwater salinites

    OpenAIRE

    Schaefer, Andrea; Remy, C.; Richards, B.S.

    2004-01-01

    An estimated 1 billion people are living both without access to clean drinking water or electricity. The small photovoltaic (PV)-powered hybrid membrane system described here is designed to address the plight of some of these people. PV and membrane technologies are chosen due to suitability for operation in remote and often harsh conditions. An ultrafiltration (UF) pre-treatment is included to remove bacteria and most pathogens, while a reverse osmosis (RO) or nanofiltration (NF)...

  15. Attachment of iron corrosion products on steam generator tube and feed-water pump in PWRs secondary system

    International Nuclear Information System (INIS)

    Operating experience of the secondary systems in PWRs indicates that scale attachment distinctly have an effect on the performance of water-steam cycle. Attached scale on outer surface of steam generator (SG) tube could induce many problems such as decrease heat efficiency of plant, corrosion of tube by intergranular attack (IGA), and choke of flow channel. Scale attached on rotor blade of feed water pump increases the driving steam consumption to keep the constant flow rate, and results in the thermal efficiency decrease of the plant. In this study, two types of test about scale deposition on equipment were executed in the conditions simulating the secondary system of PWR. One is SG model test, which simulated the circulating boiler composed of single SG tube and blow down line. The deposition rate under AVT condition was equivalent to plants revealed with extended period. High-AVT test provided useful reference, because the deposition rate of power plant is too small to measure in a short period after the beginning of High-AVT operation in Japan. The other is feed water pump model test. The mock-up pump is composed of a rotating stainless steel disk. As a result, it is confirmed that the deposition rate depends mostly on iron concentration in water and the exfoliation rate depends mainly on pH. Applying this information, the scale deposition-growth behavior on the equipment is quantitatively expressed by the model combined of scale deposition behavior and exfoliation behavior couples with the former. These results bring effective estimation for suppressing deposition-growth by the selection of water chemistry management and/or equipment improvement in the PWR secondary system. (author)

  16. Attachment of iron corrosion products on steam generator tube and feed-water pump in PWRs secondary system

    Energy Technology Data Exchange (ETDEWEB)

    Shoda, Y. [Mitsubishi Heavy Industries, Ltd., Kobe City, Hyogo (Japan); Ishihara, N.; Miyata, H. [Mitsubishi Heavy Industries, Ltd., Takasago City, Hyogo (Japan); Ohira, T. [The Japan Atomic Power Company, Tokyo (Japan); Watanabe, Y. [Hokkaido Electric Power Co., Inc., Sapporo City, Hokkaido (Japan); Nonaka, Y. [Kyushu Electric Power Co., Inc., Fukuoka City, Fukuoka (Japan)

    2010-07-01

    Operating experience of the secondary systems in PWRs indicates that scale attachment distinctly have an effect on the performance of water-steam cycle. Attached scale on outer surface of steam generator (SG) tube could induce many problems such as decrease heat efficiency of plant, corrosion of tube by intergranular attack (IGA), and choke of flow channel. Scale attached on rotor blade of feed water pump increases the driving steam consumption to keep the constant flow rate, and results in the thermal efficiency decrease of the plant. In this study, two types of test about scale deposition on equipment were executed in the conditions simulating the secondary system of PWR. One is SG model test, which simulated the circulating boiler composed of single SG tube and blow down line. The deposition rate under AVT condition was equivalent to plants revealed with extended period. High-AVT test provided useful reference, because the deposition rate of power plant is too small to measure in a short period after the beginning of High-AVT operation in Japan. The other is feed water pump model test. The mock-up pump is composed of a rotating stainless steel disk. As a result, it is confirmed that the deposition rate depends mostly on iron concentration in water and the exfoliation rate depends mainly on pH. Applying this information, the scale deposition-growth behavior on the equipment is quantitatively expressed by the model combined of scale deposition behavior and exfoliation behavior couples with the former. These results bring effective estimation for suppressing deposition-growth by the selection of water chemistry management and/or equipment improvement in the PWR secondary system. (author)

  17. Feasibility of AN Ecrh System for Jet:. Plant Layout, Auxiliaries and Services

    Science.gov (United States)

    Lennholm, M.; Bouquey, F.; Braune, H.; Farthing, J.; Garavaglia, S.; Giruzzi, G.; Granucci, G.; Jennison, M.; Parkin, A.

    2011-02-01

    A study conducted over the last year to asses the desirability and feasibility of installing an ECRH system on the JET tokamak has concluded that such a system is indeed both desirable and feasible. Details of physics studies, launcher and transmission line design, and power supplies are presented elsewhere in these proceedings. This paper concentrates on the logistical implications of installing this system at JET. The paper addresses issues such as port allocation and plant location. The study has concluded that a new building will be needed to house the ECRH plant. Building layout proposals are presented together with considerations regarding the required auxiliary equipment.

  18. Analysis of problems in application and start up of control system of steam turbine for feedwater pump%给水泵汽轮机控制系统应用及启动中的问题分析

    Institute of Scientific and Technical Information of China (English)

    毕华南; 李红艳

    2009-01-01

    论述了西门子锅炉给水泵汽轮机控制系统在发电厂的使用情况,介绍了该系统的控制原理,集中描述了转速脉冲信号(转速测量值)、转速设定值的形成,最终实现锅炉给水泵汽轮机转速控制指令的全过程.结合该系统在发电厂给水泵汽轮机中的具体应用情况,对运行过程中存在的问题及处理方法进行了简要说明.%The service condition of control system of the steam turbine for boiler feedwater pump produced by Siemens was discoursed. The control principle of the system was introduced. The all process, in which includes the measurement of speed impulse signal, the formation of speed settings, and the creation of control instruction for the steam turbine speed, were described in detail. Combining with the concrete service condition of the system in steam turbine for feedwater pump, some problems occurred in op-eration and handling methods were explained tersely.

  19. High voltage bus and auxiliary heater control system for an electric or hybrid vehicle

    Science.gov (United States)

    Murty, Balarama Vempaty

    2000-01-01

    A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

  20. Feedwater heaters functional analysis at Embalse NGS

    International Nuclear Information System (INIS)

    This study is concerned with the analysis or feedwater heaters, to detect actual failure or a bad trend beyond acceptable operating limits. When these situations are identified, preventive or corrective maintenance must be done. 2 tabs., 14 figs

  1. Header feedwater supply and power distribution stability in channel boiling water cooled reactors

    International Nuclear Information System (INIS)

    Boundaries of radial-azimuthal instability of the reactor neutron field during the supply of all feedwater and a part of it (25%) to downtake pipes of the separating drum (75% of feedwater come to distributive group headers) are found out for NPP with a RBMK type reactor. Results of computer calculation of the transient process at NPP caused by 2% step increase of nominal pressure in a head collector of a feedwater electric pump are also presented for comparison of the above methods of feed-water supply. Calculation is carried out according to the OKA program with provision for the control system of the reactor total power. It is shown that the boundary of ''mean period'' instability does not change but the reserve in respect to the ''fast'' space instability slightly increases when header feedwater supply at NPP from RBMK is used. It is noted that requirements to the pressure regulator system quick action in a separating drum are increased when the header feedwater supply is used. This fact is explained by the fact that considerable pressure drop in a separating drum occurs during some accidents (for example, at false operation of the emergensy protective system)

  2. Design, Fabrication, and Testing of an Auxiliary Cooling System for Jet Engines

    Science.gov (United States)

    Leamy, Kevin; Griffiths, Jim; Andersen, Paul; Joco, Fidel; Laski, Mark; Balser, Jeffrey (Technical Monitor)

    2001-01-01

    This report summarizes the technical effort of the Active Cooling for Enhanced Performance (ACEP) program sponsored by NASA. It covers the design, fabrication, and integrated systems testing of a jet engine auxiliary cooling system, or turbocooler, that significantly extends the use of conventional jet fuel as a heat sink. The turbocooler is designed to provide subcooled cooling air to the engine exhaust nozzle system or engine hot section. The turbocooler consists of three primary components: (1) a high-temperature air cycle machine driven by engine compressor discharge air, (2) a fuel/ air heat exchanger that transfers energy from the hot air to the fuel and uses a coating to mitigate fuel deposits, and (3) a high-temperature fuel injection system. The details of the turbocooler component designs and results of the integrated systems testing are documented. Industry Version-Data and information deemed subject to Limited Rights restrictions are omitted from this document.

  3. Steady-state dynamic behavior of an auxiliary bearing supported rotor system

    Science.gov (United States)

    Xie, Huajun; Flowers, George T.; Lawrence, Charles

    1995-01-01

    This paper investigates the steady-state responses of a rotor system supported by auxiliary bearings in which there is a clearance between the rotor and the inner race of the bearing. A simulation model based upon the rotor of a production jet engine is developed and its steady-state behavior is explored over a wide range of operating conditions for various parametric configurations. Specifically, the influence of rotor imbalance, support stiffness, and damping is studied. It is found that imbalance may change the rotor responses dramatically in terms of frequency contents at certain operating speeds. Subharmonic responses of 2nd order through 10th order are all observed except the 9th order. Chaotic phenomenon is also observed. Jump phenomena (or double-valued responses) of both hard-spring type and soft-spring type are shown to occur at low operating speeds for systems with low auxiliary bearing damping or large clearance even with relatively small imbalance. The effect of friction between the shaft and the inner race of the bearing is also discussed.

  4. Secondary coolant purification system with demineralizer bypass

    International Nuclear Information System (INIS)

    Apparatus and method are provided for a nuclear stream supply system for adequately controlling the chemistry of the secondary coolant. The invention includes means for the addition of volatile chemicals, a full flow condensate demineralizer, continuous blowdown capability, radiation detection means, a condensate demineralizer bypass line, and an auxiliary demineralizer bypass line, and an auxiliary demineralizer sized to handle full blowdown flow. The auxiliary demineralizer is cut into the system and the steam generator feedwater flow is bypassed around the full flow condensate demineralizer whenever radioactivity is detected in the secondary coolant

  5. Linear CCD attitude measurement system based on the identification of the auxiliary array CCD

    Science.gov (United States)

    Hu, Yinghui; Yuan, Feng; Li, Kai; Wang, Yan

    2015-10-01

    Object to the high precision flying target attitude measurement issues of a large space and large field of view, comparing existing measurement methods, the idea is proposed of using two array CCD to assist in identifying the three linear CCD with multi-cooperative target attitude measurement system, and to address the existing nonlinear system errors and calibration parameters and more problems with nine linear CCD spectroscopic test system of too complicated constraints among camera position caused by excessive. The mathematical model of binocular vision and three linear CCD test system are established, co-spot composition triangle utilize three red LED position light, three points' coordinates are given in advance by Cooperate Measuring Machine, the red LED in the composition of the three sides of a triangle adds three blue LED light points as an auxiliary, so that array CCD is easier to identify three red LED light points, and linear CCD camera is installed of a red filter to filter out the blue LED light points while reducing stray light. Using array CCD to measure the spot, identifying and calculating the spatial coordinates solutions of red LED light points, while utilizing linear CCD to measure three red LED spot for solving linear CCD test system, which can be drawn from 27 solution. Measured with array CCD coordinates auxiliary linear CCD has achieved spot identification, and has solved the difficult problems of multi-objective linear CCD identification. Unique combination of linear CCD imaging features, linear CCD special cylindrical lens system is developed using telecentric optical design, the energy center of the spot position in the depth range of convergence in the direction is perpendicular to the optical axis of the small changes ensuring highprecision image quality, and the entire test system improves spatial object attitude measurement speed and precision.

  6. Designs for remote inspection of the ALMR Reactor Vessel Auxiliary Cooling System (RVACS)

    International Nuclear Information System (INIS)

    One of the most important safety systems in General Electric's (GI) Advanced Liquid Metal Reactor (ALMR) is the Reactor Vessel Auxiliary Cooling System (RVACS). Because of high temperature, radiation, and restricted space conditions, GI desired methods to remotely inspect the RVACS, emissive coatings, and reactor vessel welds during normal refueling operations. The DOE/NE Robotics for Advanced Reactors program formed a team to evaluate the ALMR design for remote inspection of the RVACS. Conceptual designs for robots to perform the required inspection tasks were developed by the team. Design criteria for these remote systems included robot deployment, power supply, navigation, environmental hardening of components, tether management, communication with an operator, sensing, and failure recovery. The operation of the remote inspection concepts were tested using 3-D simulation models of the ALMR. In addition, the team performed an extensive technology review of robot components that could survive the environmental conditions in the RVACS

  7. Fuel handling machine and auxiliary systems for a fuel handling cell

    International Nuclear Information System (INIS)

    This working report is an update for as well as a supplement to an earlier fuel handling machine design (Kukkola and Roennqvist 2006). A focus in the earlier design proposal was primarily on the selection of a mechanical structure and operating principle for the fuel handling machine. This report introduces not only a fuel handling machine design but also auxiliary fuel handling cell equipment and its operation. An objective of the design work was to verify the operating principles of and space allocations for fuel handling cell equipment. The fuel handling machine is a remote controlled apparatus capable of handling intensely radiating fuel assemblies in the fuel handling cell of an encapsulation plant. The fuel handling cell is air tight space radiation-shielded with massive concrete walls. The fuel handling machine is based on a bridge crane capable of traveling in the handling cell along wall tracks. The bridge crane has its carriage provided with a carousel type turntable having mounted thereon both fixed and telescopic masts. The fixed mast has a gripper movable on linear guides for the transfer of fuel assemblies. The telescopic mast has a manipulator arm capable of maneuvering equipment present in the fuel handling cell, as well as conducting necessary maintenance and cleaning operations or rectifying possible fault conditions. The auxiliary fuel handling cell systems consist of several subsystems. The subsystems include a service manipulator, a tool carrier for manipulators, a material hatch, assisting winches, a vacuum cleaner, as well as a hose reel. With the exception of the vacuum cleaner, the devices included in the fuel handling cell's auxiliary system are only used when the actual encapsulation process is not ongoing. The malfunctions of mechanisms or actuators responsible for the motion actions of a fuel handling machine preclude in a worst case scenario the bringing of the fuel handling cell and related systems to a condition appropriate for

  8. Fuel handling machine and auxiliary systems for a fuel handling cell

    Energy Technology Data Exchange (ETDEWEB)

    Suikki, M. [Optimik Oy, Turku (Finland)

    2013-10-15

    This working report is an update for as well as a supplement to an earlier fuel handling machine design (Kukkola and Roennqvist 2006). A focus in the earlier design proposal was primarily on the selection of a mechanical structure and operating principle for the fuel handling machine. This report introduces not only a fuel handling machine design but also auxiliary fuel handling cell equipment and its operation. An objective of the design work was to verify the operating principles of and space allocations for fuel handling cell equipment. The fuel handling machine is a remote controlled apparatus capable of handling intensely radiating fuel assemblies in the fuel handling cell of an encapsulation plant. The fuel handling cell is air tight space radiation-shielded with massive concrete walls. The fuel handling machine is based on a bridge crane capable of traveling in the handling cell along wall tracks. The bridge crane has its carriage provided with a carousel type turntable having mounted thereon both fixed and telescopic masts. The fixed mast has a gripper movable on linear guides for the transfer of fuel assemblies. The telescopic mast has a manipulator arm capable of maneuvering equipment present in the fuel handling cell, as well as conducting necessary maintenance and cleaning operations or rectifying possible fault conditions. The auxiliary fuel handling cell systems consist of several subsystems. The subsystems include a service manipulator, a tool carrier for manipulators, a material hatch, assisting winches, a vacuum cleaner, as well as a hose reel. With the exception of the vacuum cleaner, the devices included in the fuel handling cell's auxiliary system are only used when the actual encapsulation process is not ongoing. The malfunctions of mechanisms or actuators responsible for the motion actions of a fuel handling machine preclude in a worst case scenario the bringing of the fuel handling cell and related systems to a condition appropriate for

  9. Summary of ACSL Simulations of the MSRE Auxiliary Charcoal Bed Vacuum System

    Energy Technology Data Exchange (ETDEWEB)

    Damiano, B

    2000-10-26

    The simulation of the Auxiliary Charcoal Bed (ACB) Vacuum System was performed to evaluate the original vacuum system design, detect and identify design deficiencies, investigate the effects of proposed corrections on system performance, and generally aid in refining the system design before construction and mockup testing. The simulation was performed by using the Advanced Continuous Simulation Language (ACSL). The vacuum system design goals are to provide approximately 20 SCFM of both booster gas and purge gas through the system and maintain a flow of approximately 40 SCFM with a velocity of 50 to 75 f/sec at the entrance to the cyclone separator. The model results showed that the original system design was incapable of meeting the system performance goals. Further simulations showed that the following modifications to the original vacuum system design were required to make the system performance acceptable; (1) Remove valve PCV4. (2) Modify the flow controllers FTC3 and FTC4 from the original flow range of 0-17.6 SCFM (0-500 SLM) to 0-35.3 SCFM (0-1000 SLM). (3) Replace the bellows sealed valves SV-1, SV-3A, SV-3B, SV-4A, and SV-4B with less restrictive ball valves. The simulation results saved considerable time and effort by identifying flaws in the original system design. Early identification of these flaws and the use of the simulation model to investigate possible solutions allowed corrective modifications to be made before construction of the mock up test facility.

  10. Design, Testing and Modeling of the Direct Reactor Auxiliary Cooling System for AHTRs

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Quiping [The Ohio State Univ., Columbus, OH (United States); Sun, Xiaodong [The Ohio State Univ., Columbus, OH (United States); Chtistensen, Richard [The Ohio State Univ., Columbus, OH (United States); Blue, Thomas [The Ohio State Univ., Columbus, OH (United States); Yoder, Graydon [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wilson, Dane [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-08

    The principal objective of this research is to test and model the heat transfer performance and reliability of the Direct Reactor Auxiliary Cooling System (DRACS) for AHTRs. In addition, component testing of fluidic diodes is to be performed to examine the performance and viability of several existing fluidic diode designs. An extensive database related to the thermal performance of the heat exchangers involved will be obtained, which will be used to benchmark a computer code for the DRACS design and to evaluate and improve, if needed, existing heat transfer models of interest. The database will also be valuable for assessing the viability of the DRACS concept and benchmarking any related computer codes in the future. The experience of making a liquid fluoride salt test facility available, with lessons learned, will greatly benefit the development of the Fluoride Salt-cooled High-temperature Reactor (FHR) and eventually the AHTR programs.

  11. Design, Testing and Modeling of the Direct Reactor Auxiliary Cooling System for AHTRs

    International Nuclear Information System (INIS)

    The principal objective of this research is to test and model the heat transfer performance and reliability of the Direct Reactor Auxiliary Cooling System (DRACS) for AHTRs. In addition, component testing of fluidic diodes is to be performed to examine the performance and viability of several existing fluidic diode designs. An extensive database related to the thermal performance of the heat exchangers involved will be obtained, which will be used to benchmark a computer code for the DRACS design and to evaluate and improve, if needed, existing heat transfer models of interest. The database will also be valuable for assessing the viability of the DRACS concept and benchmarking any related computer codes in the future. The experience of making a liquid fluoride salt test facility available, with lessons learned, will greatly benefit the development of the Fluoride Salt-cooled High-temperature Reactor (FHR) and eventually the AHTR programs.

  12. RELAP5 Analysis of OECD/NEA ROSA Project Experiment Simulating a PWR Loss-of-Feedwater Transient with High-Power Natural Circulation

    Directory of Open Access Journals (Sweden)

    Takeshi Takeda

    2012-01-01

    Full Text Available A ROSA/LSTF experiment was conducted for OECD/NEA ROSA Project simulating a PWR loss-of-feedwater (LOFW transient with specific assumptions of failure of scram that may cause natural circulation with high core power and total failure of high pressure injection system. Auxiliary feedwater (AFW was provided to well observe the long-term high-power natural circulation. The core power curve was obtained from a RELAP5 code analysis of PWR LOFW transient without scram. The primary and steam generator (SG secondary-side pressures were maintained, respectively, at around 16 and 8 MPa by cycle opening of pressurizer (PZR power-operated relief valve and SG relief valves for a long time. Large-amplitude level oscillation occurred in SG U-tubes for a long time in a form of slow fill and dump while the two-phase natural circulation flow rate gradually decreased with some oscillation. RELAP5 post-test analyses were performed to well understand the observed phenomena by employing a fine-mesh multiple parallel flow channel representation of SG U-tubes with a Wallis counter-current flow limiting correlation at the inlet of U-tubes. The code, however, has remaining problems in proper predictions of the oscillative primary loop flow rate and SG U-tube liquid level as well as PZR liquid level.

  13. Space shuttle auxiliary propulsion system design study. Phase C and E report: Storable propellants, RCS/OMS/APU integration study

    Science.gov (United States)

    Anglim, D. D.; Bruns, A. E.; Perryman, D. C.; Wieland, D. L.

    1972-01-01

    Auxiliary propulsion concepts for application to the space shuttle are compared. Both monopropellant and bipropellant earth storable reaction control systems were evaluated. The fundamental concepts evaluated were: (1) monopropellant and bipropellant systems installed integrally within the vehicle, (2) fuel systems installed modularly in nose and wing tip pods, and (3) fuel systems installed modularly in nose and fuselage pods. Numerous design variations within these three concepts were evaluated. The system design analysis and methods for implementing each of the concepts are reported.

  14. Thermal-hydraulic analysis for changing feedwater check valve leakage rate testing methodology

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, R.; Harrell, J.

    1996-12-01

    The current design and testing requirements for the feedwater check valves (FWCVs) at the Grand Gulf Nuclear Station are established from original licensing requirements that necessitate extremely restrictive air testing with tight allowable leakage limits. As a direct result of these requirements, the original high endurance hard seats in the FWCVs were modified with elastomeric seals to provide a sealing surface capable of meeting the stringent air leakage limits. However, due to the relatively short functional life of the elastomeric seals compared to the hard seats, the overall reliability of the sealing function actually decreased. This degraded performance was exhibited by frequent seal failures and subsequent valve repairs. The original requirements were based on limited analysis and the belief that all of the high energy feedwater vaporized during the LOCA blowdown. These phenomena would have resulted in completely voided feedwater lines and thus a steam environment within the feedwater leak pathway. To challenge these criteria, a comprehensive design basis accident analysis was developed using the RELAP5/MOD3.1 thermal-hydraulic code. Realistic assumptions were used to more accurately model the post-accident fluid conditions within the feedwater system. The results of this analysis demonstrated that no leak path exists through the feedwater lines during the reactor blowdown phase and that sufficient subcooled water remains in various portions of the feedwater piping to form liquid water loop seals that effectively isolate this leak path. These results provided the bases for changing the leak testing requirements of the FWCVs from air to water. The analysis results also established more accurate allowable leakage limits, determined the real effective margins associated with the FWCV safety functions, and led to design changes that improved the overall functional performance of the valves.

  15. Application of Homotopy Perturbation Method with an Auxiliary Term for Nonlinear Dropping Equations Arisen in Polymer Packaging System

    Directory of Open Access Journals (Sweden)

    Xiang Hong

    2013-01-01

    Full Text Available The homotopy perturbation method (HPM with an auxiliary term was applied to obtain approximate analytical solutions of polymer cushioning packaging system. The second-order solution of the equation of motion was obtained and compared with the numerical simulation solution solved by the Runge-Kutta algorithm. The results showed the high accuracy of this modified HPM with convenient calculation.

  16. Enhancing VHTR passive safety and economy with thermal radiation based direct reactor auxiliary cooling system

    International Nuclear Information System (INIS)

    One of the most important requirements for Gen. IV Very High Temperature Reactor (VHTR) is passive safety. Currently all the gas cooled version of VHTR designs use Reactor Vessel Auxiliary Cooling System (RVACS) for passive decay heat removal. The RVACS can be characterized as a surface-based decay heat removal system. It is especially suitable for smaller power reactors since small systems have relatively larger surface area to volume ratio. However, RVACS limits the maximum achievable power level for modular VHTRs due to the mismatch between the reactor power (proportional to the core volume) and decay heat removal capability (proportional to the vessel surface area). Besides the safety considerations, VHTRs also need to be economical in order to compete with other reactor concepts and other types of energy sources. The limit of decay heat removal capability set by using RVACS has affected the economy of VHTRs. A potential alternative solution is to use a volume-based passive decay heat removal system, called Direct Reactor Auxiliary Cooling Systems (DRACS), to remove or mitigate the limitation on decay heat removal capability. DRACS composes of natural circulation loops with two sets of heat exchangers, one on the reactor side and another on the environmental side. For the reactor side, cooling pipes will be inserted into holes made in the outer or inner graphite reflector blocks. There will be gaps or annular regions formed between these cooling pipes and their corresponding surrounding graphite surfaces. Graphite has an excellent heat conduction property. By taking advantage of this feature, we can have a volume-based method to remove decay heat. The scalability can be achieved, if needed, by employing more rows of cooling pipes to accommodate higher decay heat rates. Since heat can easily conduct through the graphite regions among the holes made for the cooling pipes, those cooling pipes located further away from the active core region can still be very

  17. Controlling the feedwater flow in a BWR. Examples from Forsmark 2

    International Nuclear Information System (INIS)

    An investigation of the feedwater controller at Forsmark 2 has been performed. The investigation is based on signal analysis of measurement signals recorded during operation of the plant during different tests. The feedwater controller consists of the water level controller, the flow controller and the condenser balance controller. The overall goal of the feedwater control is to maintain constant water level (level controller) in the reactor and at the same time balance the water levels in the two condensers (condenser balance controller) to avoid that one condenser is full of water while the other one is operated with too low level. There is also a feed forward of the difference between steam flow and feedwater flow (flow controller) for each turbine system with the aim to reduce the fluctuation in reactor water level. The relation in strength between the three controllers is such that the level controller is the strongest followed by the condenser balance controller and finally the flow controller. Tests with trip of the feedwater pump and automatic start of the spare pump in each turbine system indicates a fast reduction in reactor water level that is restored after the transient in the control system. The transient in water level is stable without oscillations. However, it takes about 100 s before the reactor water level is restored. The function of the flow controller has been questioned by the authors. It does not take the action that is expected when a disturbance takes place in the difference between steam and feedwater flow. In addition to this principal weakness there is an offset in the feedwater controller output for feedwater flow 22 that reduces the contribution in flow control that is expected during the introduction of a disturbance. This offset should be adjusted during instrument maintenance of the feedwater controller. The PIP parameters for the level controller are gain factors and time constants. These have been evaluated with the aid of

  18. Active mass damper system for high-rise buildings using neural oscillator and position controller considering stroke limitation of the auxiliary mass

    Science.gov (United States)

    Hongu, J.; Iba, D.; Nakamura, M.; Moriwaki, I.

    2016-04-01

    This paper proposes a problem-solving method for the stroke limitation problem, which is related to auxiliary masses of active mass damper systems for high-rise buildings. The proposed method is used in a new simple control system for the active mass dampers mimicking the motion of bipedal mammals, which has a neural oscillator synchronizing with the acceleration response of structures and a position controller. In the system, the travel distance and direction of the auxiliary mass of the active mass damper is determined by reference to the output of the neural oscillator, and then, the auxiliary mass is transferred to the decided location by using a PID controller. The one of the purpose of the previouslyproposed system is stroke restriction problem avoidance of the auxiliary mass during large earthquakes by the determination of the desired value within the stroke limitation of the auxiliary mass. However, only applying the limited desired value could not rigorously restrict the auxiliary mass within the limitation, because the excessive inertia force except for the control force produced by the position controller affected on the motion of the auxiliary mass. In order to eliminate the effect on the auxiliary mass by the structural absolute acceleration, a cancellation method is introduced by adding a term to the control force of the position controller. We first develop the previously-proposed system for the active mass damper and the additional term for cancellation, and verity through numerical experiments that the new system is able to operate the auxiliary mass within the restriction during large earthquakes. Based on the comparison of the proposed system with the LQ system, a conclusion was drawn regarding which the proposed neuronal system with the additional term appears to be able to limit the stroke of the auxiliary mass of the AMD.

  19. Mining a coal seam below a heating goaf with a force auxiliary ventilation system at Longhua underground coal mine, China

    Institute of Scientific and Technical Information of China (English)

    Wang Gang; Xie Jun; Xue Sheng; Wang Haiyang

    2015-01-01

    Extraction of a coal seam which lies not far below a heating goaf can be a major safety challenge. A force auxiliary ventilation system was adopted as a control method in successful extraction and recovery of the panel 30110 of the #3?1 coal seam, which is about 30–40 m below the heating goaf of the #2?2 seam at Longhua underground coal mine, Shanxi Province, China. Booster fans and ventilation control devices such as doors and regulators were used in the system. The results show that, provided that a force auxiliary ventilation system is properly designed to achieve a pressure balance between a panel and its overlying goaf, the system can be used to extract a coal seam overlain by a heating goaf. This paper describes the design, installation and performance of the ventilation system during the extraction and recovery phases of the panel 30110.

  20. Pilot application of risk informed safety margin characterization to a total loss of feedwater event

    International Nuclear Information System (INIS)

    In this paper we present the results of application of a risk-informed safety margin characterization (RISMC) approach to the analysis of a loss of feedwater (LOFW) event at a pressurized water reactor (PWR). This application considered a LOFW event with the failure of auxiliary feedwater (AFW) for which feed and bleed cooling would be required to prevent core damage. For this analysis the main parameters which impact core damage for the scenario were identified and probability distributions were constructed to represent the uncertainties associated with the parameter values. These distributions were sampled using a Latin Hypercube Sampling (LHS) technique to generate sets of sample cases to simulate using the MAAP4 code. Simulation results were evaluated to determine the safety margins relative to those obtained using typical probabilistic risk assessment (PRA) modeling (success criteria) assumptions. -- Highlights: • We apply a risk-informed approach to characterize safety margins. • This approach was applied to of a loss of feedwater event at a pressurized water reactor. • Probability distributions for the important parameter values were constructed. • These distributions were sampled to generate MAAP4 code simulation cases. • Simulation results were evaluated to determine the safety margins

  1. Enhancing VHTR Passive Safety and Economy with Thermal Radiation Based Direct Reactor Auxiliary Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Haihua Zhao; Hongbin Zhang; Ling Zou; Xiaodong Sun

    2012-06-01

    One of the most important requirements for Gen. IV Very High Temperature Reactor (VHTR) is passive safety. Currently all the gas cooled version of VHTR designs use Reactor Vessel Auxiliary Cooling System (RVACS) for passive decay heat removal. The decay heat first is transferred to the core barrel by conduction and radiation, and then to the reactor vessel by thermal radiation and convection; finally the decay heat is transferred to natural circulated air or water systems. RVACS can be characterized as a surface based decay heat removal system. The RVACS is especially suitable for smaller power reactors since small systems have relatively larger surface area to volume ratio. However, RVACS limits the maximum achievable power level for modular VHTRs due to the mismatch between the reactor power (proportional to volume) and decay heat removal capability (proportional to surface area). When the relative decay heat removal capability decreases, the peak fuel temperature increases, even close to the design limit. Annular core designs with inner graphite reflector can mitigate this effect; therefore can further increase the reactor power. Another way to increase the reactor power is to increase power density. However, the reactor power is also limited by the decay heat removal capability. Besides the safety considerations, VHTRs also need to be economical in order to compete with other reactor concepts and other types of energy sources. The limit of decay heat removal capability set by using RVACS has affected the economy of VHTRs. A potential alternative solution is to use a volume-based passive decay heat removal system, called Direct Reactor Auxiliary Cooling Systems (DRACS), to remove or mitigate the limitation on decay heat removal capability. DRACS composes of natural circulation loops with two sets of heat exchangers, one on the reactor side and another on the environment side. For the reactor side, cooling pipes will be inserted into holes made in the outer or

  2. Holistic Modeling, Design & Analysis of Integrated Stirling and Auxiliary Clean Energy Systems for Combined Heat and Power Applications

    Science.gov (United States)

    Nayak, Amrit Om

    The research revolves around the development of a model to design and analyze Stirling systems. Lack of a standard approach to study Stirling systems and difficulty in generalizing existing approaches pose stiff challenges. A stable mathematical model (integrated second order adiabatic and dynamic model) is devised and validated for general use. The research attempts to design compact combined heat and power (CHP) system to run on multiple biomass fuels and solar energy. Analysis is also carried out regarding the design of suitable auxiliary systems like thermal energy storage system, biomass moisture removal system and Fresnel solar collector for the CHP Stirling system.

  3. CPR1000非能动应急给水系统瞬态特性分析%Transient Analysis of Passive Emergency Feedwater System of CPR1O00

    Institute of Scientific and Technical Information of China (English)

    张亚培; 田文喜; 秋穗正; 苏光辉

    2011-01-01

    The transient thermal hydraulic characteristics of CPR1000 were analyzed by using RELAP5/MOD3. 4 code to verify the capability of the passive emergency feedwa-ter system (PEFWS) for accident mitigation under the condition of station blackout accident (SBO). The calculation results show that the PEFWS of CPR1000 can supply the water to steam generator immediately and remove the core residual heat after the SBO successfully, and it also shows that the design of the PEFWS of CPR1000 is successful.%利用RELAP5/MOD3.4程序对CPR1000压水堆在全厂断电事故下一回路主要参数的瞬态热工水力特性进行分析,验证CPR1000非能动应急给水系统(PEFWS)对事故的缓解能力.计算结果表明,CPR1000在发生全厂断电事故后,PEFWS完全可及时向蒸汽发生器补水,同时导出堆芯余热,保证反应堆处于安全状态,从而验证CPR1000 PEFWS的设计成功.

  4. PS auxiliary magnet

    CERN Multimedia

    1974-01-01

    Units of the PS auxiliary magnet system. The picture shows how the new dipoles, used for vertical and horizontal high-energy beam manipulation, are split for installation and removal so that it is not necessary to break the accelerator vacuum. On the right, adjacent to the sector valve and the windings of the main magnet, is an octupole of the set.

  5. Synchronous dynamics of a coupled shaft/bearing/housing system with auxiliary support from a clearance bearing: Analysis and experiment

    Science.gov (United States)

    Lawen, James L., Jr.; Flowers, George T.

    1995-01-01

    This study examines the response of a flexible rotor supported by load sharing between linear bearings and an auxiliary clearance bearing. The objective is to develop a better understanding of the dynamical behavior of a magnetic bearing supported rotor system interacting with auxiliary bearings during a critical operating condition. Of particular interest is the effect of coupling between the bearing/housing and shaft vibration on the rotordynamical responses. A simulation model is developed and a number of studies are performed for various parametric configurations. An experimental investigation is also conducted to compare and verify the rotordynamic behavior predicted by the simulation studies. A strategy for reducing synchronous shaft vibration through appropriate design of coupled shaft/bearing/housing vibration modes is identified.

  6. 面向进水电磁阀性能测试的恒压恒流供水系统设计%Design of Constant Pressure & Flow Water Supply System for Feedwater Electromagnetic Valve Performance Testing

    Institute of Scientific and Technical Information of China (English)

    郑敦衍; 詹培德; 洪晓斌

    2013-01-01

    Facing to multistage hydraulic control problem of dishwasher and its feedwater electromagnetic valve performance testing, the process of electromagnetic valve performance testing was introduced and constant pressure&flow water supply system was designed based on the requirements of electromagnetic valve performance test. The constant pressure control circuit, constant flow control circuit, signal detection circuit of hall flow sensor and control software were designed through the analysis of constant pressure&flow water supply system principle. Finally, experiments were conducted in the constant pressure&flow water supply system. The experiment results showed that constant pressure&flow regulation was rapid, and the error between prevalue after the regulation and actual value was very small. Therefore, the constant pressure & flow water supply system can meet the testing requirements of various kinds of hydraulic pressures and water flow.%针对洗衣机及洗碗机进水电磁阀性能检测中的多级水压控制问题,首先介绍电磁阀性能测试流程,根据电磁阀性能测试要求进行恒压恒流供水系统设计。通过分析恒压恒流供水系统原理,设计出恒压控制电路、恒流控制电路、霍耳型流量传感器信号检测电路及控制流程,最后对恒压恒流供水系统进行应用实验。实验结果表明:恒压恒流调节控制快速,且调节后预置值与实际值误差较小,可以满足各种水压、水流量测试要求。

  7. Mechanical (turbines and auxiliary equipment)

    CERN Document Server

    Sherry, A; Cruddace, AE

    2013-01-01

    Modern Power Station Practice, Volume 3: Mechanical (Turbines and Auxiliary Equipment) focuses on the development of turbines and auxiliary equipment used in power stations in Great Britain. Topics covered include thermodynamics and steam turbine theory; turbine auxiliary systems such as lubrication systems, feed water heating systems, and the condenser and cooling water plants. Miscellaneous station services, and pipework in power plants are also described. This book is comprised of five chapters and begins with an overview of thermodynamics and steam turbine theory, paying particular attenti

  8. Dispersant application: (1) during steam generator wet layup for removal of existing deposits, and (2) during the long-path recirculation cleanup process of the condensate/feedwater system to reduce startup corrosion product transport to the steam generators

    International Nuclear Information System (INIS)

    management operations (e.g., sludge lancing, chemical cleaning, etc.). In 2009 EPRI worked with Exelon Corporation to develop and implement a plan for a trial dispersant application during the SG wet layup at Three Mile Island Unit 1 (TMI-1). Because the SGs were scheduled for replacement during the Fall 2009 outage, this trial represented a unique opportunity to evaluate the efficacy of a dispersant wet layup application with minimal risk to the SGs. This paper discusses the technical bases supporting the addition of dispersant during wet layup at TMI-1 and the results of the Fall 2009 trial application. Additional applications, under EPRI sponsorship, have either just taken place (Doel 3 in Summer 2010) or are planned (Braidwood 1 in Fall 2010). It is anticipated that addition of a dispersant during the long-path recirculation cleanup process will more readily clean up transportable corrosion products from the system and increase their retention time in solution, thereby increasing the amount of iron removed from the condensate and feedwater systems prior to initiation of flow to the SGs. Evaluations preparing for applications of this type include: Reviews of the procedure and general characteristics of the long-path recirculation cleanup process at three plants: Byron Unit 1, Millstone Unit 2 and Three Mile Island (TMI) Unit 1; A laboratory test program to assess dispersant efficacy under the conditions present during the long-path recirculation cleanup process. A number of different dispersant chemicals, including the polyacrylic acid (PAA) used in online applications, were investigated; Generic and plant-specific evaluations (for the above three units) of the compatibility of PAA with the secondary system components anticipated to be wetted during the long-path recirculation cleanup process. Based on the results of this study, inputs concerning the recommended dispersant chemical, concentration, application schedule, and cleanup criteria were generated to aid interested

  9. Checking earthquake resistance of feedwater pump

    International Nuclear Information System (INIS)

    The dynamic behavior of rotors of feedwater pumps for WWER-1000 nuclear power plants was analyzed with respect to seismic excitation. Mathematical determination of the transient state and of the maximum amplitude of the forced rotor vibration is described in detail. The results of the analysis give evidence that the pump rotor is earthquake-resistant. Its first critical revolutions of bending-circulation oscillations have a value of 75 Hz, which is well above the seismic excitation band. The forced vibration amplitude does not exceed the value of 0.02 mm, which is lower than the clearance of the runner packing rings. (Z.M.). 4 figs., 5 refs

  10. Improved plant economics through accurate feedwater flow measurement with the crossflow ultrasonic flowmeter

    International Nuclear Information System (INIS)

    The crossflow ultrasonic flowmeter (UFM) improves nuclear power plant performance through more accurate and reliable feedwater flow measurement. Reactor power levels are typically monitored via secondary-side calorimetric calculations that depend on the accurate measurement of feedwater flow . The feedwater flow is measured with calibrated venturis in most plants. These are subject to chemical fouling and other mechanical problems. If the loss in accuracy of the feedwater flow measurement overstates the actual flow rate, the result is a direct loss in megawatts generated by the plant. This paper describes a new, innovative ultrasonic technique to improve the accuracy, stability and repeatability of ultrasonic flow measurements. By employing this advanced technology to provide a continuous correction to the venturi-measured feed water flow rate, plants have reported the recovery of between 5 and 25 MWe. This technology has been implemented in a new flowmeter called CROSSFLOW. The CROSSFLOW meter utilizes a mathematical process called cross-correlation to process the ultrasonic signal, which is modulated by the flow eddys to determine the velocity of the feedwater. It replaces the older, less accurate transit-time methodology. Comparisons with weigh tank test, calibrated plant instrumentation, and chemical tracer tests have demonstrated a repeatable accuracy of 0.21% or better with this advanced cross-correlation technology. The paper discusses the history of the cross-correlation technique and its theoretical basis, illustrates how this technique addresses the measurement sensitivities for various parameters, demonstrates the calculation of the accuracy of the meter, and discusses the recently completed NRC review of the CROSSFLOW System and methodology. The paper also discusses recent precision flow measurement applications being performed with CROSSFLOW at nuclear plants worldwide. Among these applications are the measurement of Reactor Coolant System flow and the

  11. Determination of the thermal loadings affecting the auxiliary lines of the reactor coolant system in French PWR plants

    International Nuclear Information System (INIS)

    The various incidents, imputed to thermal fatigue, which occurred throughout the world on the auxiliary lines of Reactor Coolant System (SIS, RHR, CVC), led EDF to urge a research program in order to determine the origins and the consequences of these problems for the French nuclear power plants. In 1992, following the crossing crack discovered at Dampierre 2 on the un-isolable part of a Safety Injection System pipe, a program of instrumentation was defined and is described in this paper. Among the objectives, two of the principal goals were to determine the thermal loadings really supported by the various lines and to highlight the thermal hydraulic phenomena affecting them. Indeed, in order to explain the discovered damages, it was essential to know the real thermal loadings to compare them with those of design and to carry out mechanical calculations of resistance to thermal fatigue. The instrumentations installed on the 900 MW units enabled to check the resistance with the fatigue of all the auxiliary lines in spite of significant differences between the real loadings and those envisaged at the design. They contributed to the knowledge improvement on the local thermal hydraulic phenomena but the incidents at Dampierre 1 showed that this knowledge is still imperfect. The results of these instrumentations are also used for the design of the future units by the use of the feedback of several cycles of acquisition on the 900 MW units, but also 1300 MW and 1450 MW since similar instrumentations were installed on the auxiliary lines in Golfech 2 and Chooz B1

  12. Integrated experimental test program on waterhammer pressure pulses and associated structural responses within a feedwater sparger

    Energy Technology Data Exchange (ETDEWEB)

    Nurkkala, P.; Hoikkanen, J. [Imatran Voima Oy, Vantaa (Finland)

    1997-12-31

    This paper describes the methods and systems as utilized in an integrated experimental thermohydraulic/mechanics analysis test program on waterhammer pressure pulses within a revised feedwater sparger of a Loviisa generation VVER-440-type reactor. This program was carried out in two stages: (1) measurements with a strictly limited set of operating parameters at Loviisa NPP, and (2) measurements with the full set of operating parameters on a test article simulating the revised feedwater sparger. The experiments at Loviisa NPS served as an invaluable source of information on the nature of waterhammer pressure pulses and structural responses. These tests thus helped to set the objectives and formulate the concept for series of tests on a test article to study the water hammer phenomena. The heavily instrumented full size test article of a steam generator feedwater sparger was placed within a pressure vessel simulating the steam generator. The feedwater sparger was subjected to the full range of operating parameters which were to result in waterhammer pressure pulse trains of various magnitudes and duration. Two different designs of revised feedwater sparger were investigated (i.e. `grounded` and `with goose neck`). The following objects were to be met within this program: (1) establish the thermohydraulic parameters that facilitate the occurrence of water hammer pressure pulses, (2) provide a database for further analysis of the pressure pulse phenomena, (3) establish location and severity of these water hammer pressure pulses, (4) establish the structural response due to these pressure pulses, (5) provide input data for structural integrity analysis. (orig.). 3 refs.

  13. 46 CFR 58.01-35 - Main propulsion auxiliary machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Main propulsion auxiliary machinery. 58.01-35 Section 58... AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-35 Main propulsion auxiliary machinery. Auxiliary machinery vital to the main propulsion system must be provided in duplicate unless the...

  14. Teleporting an unknown quantum state with unit fidelity and unit probability via a non-maximally entangled channel and an auxiliary system

    Science.gov (United States)

    Rashvand, Taghi

    2016-08-01

    We present a new scheme for quantum teleportation that one can teleport an unknown state via a non-maximally entangled channel with certainly, using an auxiliary system. In this scheme depending on the state of the auxiliary system, one can find a class of orthogonal vectors set as a basis which by performing von Neumann measurement in each element of this class Alice can teleport an unknown state with unit fidelity and unit probability. A comparison of our scheme with some previous schemes is given and we will see that our scheme has advantages that the others do not.

  15. Study on application of T-S fuzzy neural method in once through steam generator feedwater control

    International Nuclear Information System (INIS)

    Considering the problems of small water inventory and inferior heat accumulation capacity of the secondary side of the once through steam generator (OTSG) , and the need of rapid match of feedwater flowrate and the reactor power to ensure the steam quality, the T-S fuzzy neural method is incorporated into the OTSG feedwater control system to design a T-S fuzzy neural controller based on input and output data acquired by numerical simulation. The control results are verified by simulation method. The simulation results show that the control results under this control manner are better than those under the PID control manner and meet the control requirements satisfactorily. (authors)

  16. 46 CFR 61.20-3 - Main and auxiliary machinery and associated equipment, including fluid control systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Main and auxiliary machinery and associated equipment... SECURITY (CONTINUED) MARINE ENGINEERING PERIODIC TESTS AND INSPECTIONS Periodic Tests of Machinery and Equipment § 61.20-3 Main and auxiliary machinery and associated equipment, including fluid control...

  17. Optimal control strategy in the design of a PWR feedwater controller

    International Nuclear Information System (INIS)

    A design approach and available preliminary results are presented of work currently in progress to develop a modern alternative to the classical (present day) three-element analog steam generator water level control system for pressurized water reactors. The new control scheme is a digital feedwater controller design based on concepts of modern control theory. A basic approach is outlined which can be readily understood by industry engineers briefly acquainted with the modern control theory. A nonlinear dynamic steam generator model is developed to reasonably simulate the transient behavior of steam generator water level during typical control system transients. Deterministic optimal linear regulator theory is used to develop a multivariable feedwater controller for the steam generator and feedwater system linearized about several operating points. This controller design is now directly applicable for high power control of dry and saturated feedring-type steam generators only. Transient control performance of the feedback portion of the optimal controller is tested in computer simulation with a high-order nonlinear full plant model. Preliminary results show that the design has potential for better control performance than that of the present day control system

  18. Plant data comparisons for Comanche Peak 1/2 main feedwater pump trip transient

    Energy Technology Data Exchange (ETDEWEB)

    Boatwright, W.J.; Choe, W.G; Hiltbrand, D.W. [TU Electric, Dallas, TX (United States)] [and others

    1995-09-01

    A RETRAN-02 MOD5 model of Comanche Peak Steam Electric Station was developed by TU Electric for the purpose of performing core reload safety analyses. In order to qualify this model, comparisons against plant transient data from a partial loss of main feedwater flow were performed. These comparisons demonstrated that good representations of the plant response could be obtained with RETRAN-02 and the user-developed models of the primary-to-secondary heat transfer and plant control systems.

  19. Transient simulation of feedwater vaporization during a DBA LOP/LOCA using RELAP5/MOD3.1

    Energy Technology Data Exchange (ETDEWEB)

    Harrell, J.R. [ENERCON Services, Inc., Atlanta, GA (United States); Fuller, R.W. [Entergy Operations, Inc., Port Gibson, MS (United States)

    1996-07-01

    The current design and testing requirements for the feedwater check valves (FWCVs) at the Grand Gulf Nuclear Station (GGNS) are established from original licensing requirements that necessitate extremely restrictive air testing with tight allowable leakage limits. As a direct result of these requirements, the original high endurance hard seats in the FWCVs were modified with elastomeric seals to provide a sealing surface capable of meeting the stringent air leakage limits. However, due to the relatively short functional life of the elastomeric seals compared to the hard seats, the overall reliability of the sealing function actually decreased. The original design and testing requirements were based on limited analysis and the belief that all of the high energy feedwater vaporized during the LOCA blowdown. These phenomena would have resulted in completely voided feedwater lines and thus a steam environment within the feedwater leak pathway. Given this condition, the appropriate testing criteria would be based on air with a relatively tight allowable limit. To challenge these criteria, a comprehensive design basis accident analysis was developed using the RELAP5/MOD3.1 thermal-hydraulic code. Realistic assumptions were used to more accurately model the post-accident fluid conditions within the feedwater system. The results of this analysis demonstrated that no leakage flow exists from the reactor vessel to the condenser through the feedwater piping during the reactor vessel blowdown phase. The analysis results also established more accurate allowable leakage limits, determined the real effective margins associated with the FWCV safety functions, and led to design changes that improved the overall functional performance of the valves.

  20. Solar-auxiliary Coal-fired Power Generation System Thermal Economic Analysis%太阳能辅助燃煤发电系统经济性分析

    Institute of Scientific and Technical Information of China (English)

    葛晓霞; 邵娜; 邵成; 钱晨; 姜晨峰

    2015-01-01

    介绍了太阳能辅助锅炉受热面替代部分省煤器作用和太阳能辅助给水回热加热的两种发电系统。应用等效热降法对这两种太阳能辅助燃煤发电集成方案的热经济指标进行了计算与比较,选择了太阳能辅助给水回热加热为优化的集成方案。对槽式集热器的换热效率,光热电转换效率及投资节煤比3个技术经济性相关指标进行研究,在太阳能辅助给水回热加热的方案中,通过综合比较利用太阳能产生的汽替换各级抽汽的计算结果后,得出了替换第六级抽汽最为合理的结论。%Two power generation systems were introduced about solar assisted part replace of boiler economizer heating surface effects and the solar-assisted heating feed water regenerator .It was calculated and compared these two types of solar assisted heat economic indicators coal-fired integrated solutions by using of Equivalent Heat Drop .It was selected a solar-assisted water heating for the optimization of regenerative integrated solution ., Three related indicators of technical and economic were studied On heat transfer efficiency of trough collector and the light thermoelectric conversion efficiency as well as investment in coal saving ratio .In the solar thermal heating auxiliary feedwater back scheme , By comprehensive comparison of the use of solar energy to produce steam to replace the calculation of results at all levels extraction .It was obtained the most reasonable conclusion of replacing sixth stage extraction .

  1. Monitoring the performance of Aux. Feedwater Pump using Smart Sensing Model

    Energy Technology Data Exchange (ETDEWEB)

    No, Young Gyu; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2015-10-15

    Many artificial intelligence (AI) techniques equipped with learning systems have recently been proposed to monitor sensors and components in NPPs. Therefore, the objective of this study is the development of an integrity evaluation method for safety critical components such as Aux. feedwater pump, high pressure safety injection (HPSI) pump, etc. using smart sensing models based on AI techniques. In this work, the smart sensing model is developed at first to predict the performance of Aux. feedwater pump by estimating flowrate using group method of data handing (GMDH) method. If the performance prediction is achieved by this feasibility study, the smart sensing model will be applied to development of the integrity evaluation method for safety critical components. Also, the proposed algorithm for the performance prediction is verified by comparison with the simulation data of the MARS code for station blackout (SBO) events. In this study, the smart sensing model for the prediction performance of Aux. feedwater pump has been developed. In order to develop the smart sensing model, the GMDH algorithm is employed. The GMDH algorithm is the way to find a function that can well express a dependent variable from independent variables. This method uses a data structure similar to that of multiple regression models. The proposed GMDH model can accurately predict the performance of Aux.

  2. Computation of dynamical correlation functions for many-fermion systems with auxiliary-field quantum Monte Carlo

    Science.gov (United States)

    Vitali, Ettore; Shi, Hao; Qin, Mingpu; Zhang, Shiwei

    2016-08-01

    We address the calculation of dynamical correlation functions for many fermion systems at zero temperature, using the auxiliary-field quantum Monte Carlo method. The two-dimensional Hubbard hamiltonian is used as a model system. Although most of the calculations performed here are for cases where the sign problem is absent, the discussions are kept general for applications to physical problems when the sign problem does arise. We study the use of twisted boundary conditions to improve the extrapolation of the results to the thermodynamic limit. A strategy is proposed to drastically reduce finite size effects relying on a minimization among the twist angles. This approach is demonstrated by computing the charge gap at half filling. We obtain accurate results showing the scaling of the gap with the interaction strength U in two dimensions, connecting to the scaling of the unrestricted Hartree-Fock method at small U and Bethe ansatz exact result in one dimension at large U . An alternative algorithm is then proposed to compute dynamical Green functions and correlation functions which explicitly varies the number of particles during the random walks in the manifold of Slater determinants. In dilute systems, such as ultracold Fermi gases, this algorithm enables calculations with much more favorable complexity, with computational cost proportional to basis size or the number of lattice sites.

  3. [Study on mechanism of Salvia miltiorrhiza treating cardiovascular disease through auxiliary mechanism elucidation system for Chinese medicine].

    Science.gov (United States)

    He, Shuai-bing; Zhang, Bai-xia; Wang, Hui-hui; Wang, Yun; Qiao, Yan-jiang

    2015-10-01

    Salvia miltiorrhiza is a traditional Chinese medicine (TCM) and is widely used as a clinically medication for its efficiency in treating cardiovascular disease. Due to TCM is a comprehensive system, the mechanism of S. miltiorrhiza treating cardiovascular disease through integrated multiple pathways are still unclear in some aspects. With the rapid progress of bioinformatics and systems biology, network pharmacology is considered as a promising approach toward reveal the underlying complex relationship between an herb and the disease. In order to discover the mechanism of S. miltiorrhiza treating cardiovascular disease systematically, we use the auxiliary mechanism elucidation system for Chinese medicine, built up a molecule interaction network on the active component targets of S. miltiorrhiza and the therapeutic targets of cardiovascular disease to offer an opportunity for deep understanding the mechanism of S. miltiorrhiza treating cardiovascular disease from the perspective of network pharmacology. The results showed that S. miltiorrhiza treating cardiovascular disease through ten pathways as follows: improve lipid metabolism, anti-inflammation, regulate blood pressure, negatively regulates blood coagulation factor and antithrombotic, regulate cell proliferation, anti-stress injury, promoting angiogenesis, inhibited apoptosis, adjust vascular systolic and diastolic, promoting wound repair. The results of this paper provide theoretical guidance for the development of new drugs to treat cardiovascular disease and the discovery of new drugs through component compatibility. PMID:26975090

  4. Optimal Scheduling of a Battery Energy Storage System with Electric Vehicles’ Auxiliary for a Distribution Network with Renewable Energy Integration

    Directory of Open Access Journals (Sweden)

    Yuqing Yang

    2015-09-01

    Full Text Available With global conventional energy depletion, as well as environmental pollution, utilizing renewable energy for power supply is the only way for human beings to survive. Currently, distributed generation incorporated into a distribution network has become the new trend, with the advantages of controllability, flexibility and tremendous potential. However, the fluctuation of distributed energy resources (DERs is still the main concern for accurate deployment. Thus, a battery energy storage system (BESS has to be involved to mitigate the bad effects of DERs’ integration. In this paper, optimal scheduling strategies for BESS operation have been proposed, to assist with consuming the renewable energy, reduce the active power loss, alleviate the voltage fluctuation and minimize the electricity cost. Besides, the electric vehicles (EVs considered as the auxiliary technique are also introduced to attenuate the DERs’ influence. Moreover, both day-ahead and real-time operation scheduling strategies were presented under the consideration with the constraints of BESS and the EVs’ operation, and the optimization was tackled by a fuzzy mathematical method and an improved particle swarm optimization (IPSO algorithm. Furthermore, the test system for the proposed strategies is a real distribution network with renewable energy integration. After simulation, the proposed scheduling strategies have been verified to be extremely effective for the enhancement of the distribution network characteristics.

  5. Solutions of system of P1 equations without use of auxiliary differential equations coupled

    International Nuclear Information System (INIS)

    The system of P1 equations is composed by two equations coupled itself one for the neutron flux and other for the current. Usually this system is solved by definitions of two integrals parameters, which are named slowing down densities of the flux and the current. Hence, the system P1 can be change from integral to only two differential equations. However, there are two new differentials equations that may be solved with the initial system. The present work analyzes this procedure and studies a method, which solve the P1 equations directly, without definitions of slowing down densities. (author)

  6. Fracture of feedwater pipe in Surry unit-2 reactor

    International Nuclear Information System (INIS)

    A trip occurred in the Surry unit-2 reactor at 14 : 21 on December 9, 1986, when the reactor was being operated at full power. Recently, the power company published a detailed report on the accident and an inspection report was released by the U.S. Nuclear Regulator Commission (NRC), suggesting that the fracture had resulted from corrosion in an elbow. Thus, the present report discusses in detail the rupture of the elbow, which was part of the secondary cooler feedwater pipe. The rupture was of the guillotine mode and took place instantaneously. Immediately after the reactor trip started, the three main steam valve systems closed and then the rupture of the elbow occurred. Visual examination has shown that the wall of the elbow had become smaller in thickness. A dimple pattern was found in the fracture surface, indicating that the rupture was of the ductile breaking type. It has been concluded that this extreme decrease in wall thickness was the result of corrosion. An ultrasonic test has detected some local pitting corrosion portions in the neighborhood of the longitudinal welding seam. No unusual microscopic metal structures were detected by microscopy. Macroscopic observation revealed that small defects had been formed along the fracture surface. (Nogami, K.)

  7. BIOFEAT: Biodiesel fuel processor for a vehicle fuel cell auxiliary power unit. Study of the feed system

    Science.gov (United States)

    Sgroi, M.; Bollito, G.; Saracco, G.; Specchia, S.

    An integrated auxiliary power unit (APU) based on a 10 kW e integrated biodiesel fuel processor has been designed and is being developed. Auto-thermal reforming (ATR) and thermal cracking (TC) were considered for converting the fuel into a hydrogen-rich gas suitable for PEM fuel cells. The fuel processor includes also a gas clean-up system that will reduce the carbon monoxide in the primary processor exit gas to below 10 ppm via a new heat-integrated CO clean-up unit, based on the assembly of catalytic heat exchange plates, so as to meet the operational requirements of a PEMFC stack. This article is devoted to the study and selection of the proper feed strategy for the primary fuel processor. Different pre-treatment and feed alternatives (e.g. based on nozzles or simple coils) were devised and tested for the ATR processors, which turned out to be the preferred primary processing route. A nozzle-based strategy was finally selected along with special recommendations about the constituent materials and the operating procedures to be adopted to avoid coking and nozzle corrosion as well as to allow a wide turn down ratio.

  8. Auxiliary control system of the safety parameters for IPR-R1 reactor

    International Nuclear Information System (INIS)

    This paper deals with the description of the control of three cooling water parameters, as well as the percent power fraction of the nuclear research reactor IPR-R1. In order to keep the reactor in good operation conditions, a permanent and accurate control of the cooling water is needed. This is achieved through this system, which allows the simultaneous measurement of the water parameters such as: conductivity, temperature and the maximum and minimum water levels. The monitoring of a fourth parameter, the percent power fraction, is obtained through the control of the uncompensated ion chamber current and aims to avoid the operation of the reactor without running the cooling system. (Author)

  9. Comparative Analysis on Several Operation Schemes for Raw Water Heater of Boiler Feedwater Treatment System%几种锅炉补给水处理系统原水加热器运行方案的分析比较

    Institute of Scientific and Technical Information of China (English)

    童晓凡; 潘灯

    2016-01-01

    Due to low temperature of raw water in boiler feedwater treatment system, high-quality steam is used for heating that consumes too much energy. Therefore, the paper proposes to use waste heat from power plant circulating cooling water to heat raw water of boiler feedwater treatment system. The paper analyzes four operation schemes for raw water heater system, aiming to recycle part of the waste heat. Through technical and economic comparison, the paper presents a scheme of combing hot water heater with steam heater to save energy, reduce emissions as well as meet requirements of different operating conditions. The scheme is char-acterized by its higher integrated index of economical efficiency and performance.%针对目前锅炉补给水处理系统因原水温度低,而利用高品质蒸汽加热耗费能源的现象,提出利用发电厂循环冷却水的余热,加热锅炉补给水处理系统的原水。分析了4种原水加热器系统运行方案,目的在于回收部分废弃的热量。通过技术和经济性比较,给出采用热水加热器和蒸汽加热器配合使用方案,达到节能减排,同时满足各种运行工况需求,综合经济性能指标较高。

  10. Auxiliary control system of the safety parameters for IPR-R1 reactor

    International Nuclear Information System (INIS)

    This paper deals with the description for the control of three cooling water parameters (conductivity, temperature and the maximum and minimum water levels) as well as the percent power fraction of the nuclear research reactor IPR-R1. In order to keep the reactor in good operation conditions, one permanent and accurate control of the cooling water is needed. The double monitoring of a fourth parameter, part of the original design, the percent power fraction, is obtained through the control of the uncompensated ion chamber current and aims to avoid the operation of the reactor without running the cooling system. (Author)

  11. Cost Effective, High Efficiency Integrated Systems Approach To Auxiliary Electric Motors

    Energy Technology Data Exchange (ETDEWEB)

    Roy Kessinger; Kanchan Angal; Steve Brewer; Steve Kraihanzel; Lenny Schrank; Jason Wolf

    2003-07-15

    The CARAT program, carried out by Kinetic Art & Technology Corporation (KAT), has been one of the most commercially successful KAT R&D programs to date. Based on previous development of its technology, KAT designed, constructed and tested a highly efficient motor and controller system under this CARAT program with supplemental commercial funding. Throughout this CARAT effort, the technical objectives have been refined and refocused. Some objectives have been greatly expanded, while others have been minimized. The determining factor in all decisions to refocus the objectives was the commercial need, primarily the needs of KAT manufacturing partners. Several companies are employing the resulting CARAT motor and controller designs in prototypes for commercial products. Two of these companies have committed to providing cost share in order to facilitate the development. One of these companies is a major manufacturing company developing a revolutionary new family of products requiring the ultra-high system efficiency achievable by the KAT motor and controller technologies (known as Segmented ElectroMagnetic Array, or SEMA technology). Another company requires the high efficiency, quiet operation, and control characteristics afforded by the same basic motor and controller for an advanced air filtration product. The combined annual production requirement projected by these two companies exceeds one million units by 2005.

  12. Support on water chemistry and processes for nuclear power plant auxiliary systems

    International Nuclear Information System (INIS)

    In particular PHWRs have a system devoted to the purification and upgrading of the collected heavy water leaks. The purification train is fed with different degradation ratios (D2O/H2O), activities and impurities. The water is distilled in a packed bed column filled with a mesh type packing. The mesh wire is made of a bronze substrate covered by copper oxides whose current composition has been determined by Moessbauer spectroscopy. With the purpose of minimizing the column stack corrosion, the water is pre-treated in a train consisting of an activated charcoal bed-strong cationic-anionic resin and a final polishing mixed bed resin. Ionic chemicals like acetic acid (whose provenance is suspected to come from the air treatment/D2O recovery system where the regeneration is performed at high temperature) are detected by the conductivity and ion chromatography when they concentrate at the column bottom. Traces of oils are retained by the charcoal bed but some compounds extracted by the aqueous phase are suspected to be responsible for the resins fouling or precursors of potentially aggressive agents inside the distillation column. Those species have been detected and identified by gaseous chromatography-mass spectrometry (GC-MS). In the present work, the identification, evaluation of alternatives for the retention and results compared to the original products present in the water upgrading purification train have been summarized. (authors)

  13. Research on Simulation of Marine Auxiliary Boiler System%船舶辅锅炉系统的仿真研究

    Institute of Scientific and Technical Information of China (English)

    刘鸿儒; 万隆君; 徐轶群

    2015-01-01

    In order to study the object of marine auxiliary boiler control system operation, we have researched its function and features, designed development platform using unity3D and accomplished the simulation of roaming and control operation of marine auxiliary boiler control system. Meantime taking roaming and water system control for example, we have introduced marine auxiliary boiler control system operation training simulation,the design thinking and effect of assessment system under this platform.%以船舶辅锅炉系统控制操作为对象,研究了其功能和特性,设计以Unity 3D作为开发平台,实现对船舶辅锅炉系统的漫游和控制操作仿真。同时以漫游和水系统控制操作实现为例,介绍在该平台下设计船舶辅锅炉控制系统仿真操作训练与评估系统的设计思路和效果。

  14. Auxiliary verbs in Dinka

    DEFF Research Database (Denmark)

    Andersen, Torben

    2007-01-01

    Dinka, a Western Nilotic language, has a class of auxiliary verbs which is remarkable in the following four respects: (i) It is unusually large, comprising some 20 members; (ii) it is grammatically homogeneous in terms of both morphology and syntax; (iii) most of the auxiliary verbs correspond...... to adverbs in languages like English, while the rest are tense-aspect markers; and (iv) it is possible to combine several auxiliary verbs in a single clause. For some of the auxiliary verbs there are extant full verbs from which they have evolved. To some extent, therefore, it is possible to observe what...... semantic changes the auxiliary verbs have undergone or are undergoing during the process of grammaticalization....

  15. Evaluation of the performance of the systems cooling auxiliary of the Almaraz NPP turbine building; Evaluacion del rendimiento de los sistemas de refrigeracion auxiliar del edificio de turbinas de CNA

    Energy Technology Data Exchange (ETDEWEB)

    Vilar Carmona, G.

    2011-07-01

    After the successive performance improvements, to evacuate the thermal loads, and maintain acceptable temperatures throughout the year, added an auxiliary cooling system of the building of turbine, TCA system, composed of 5 shot forced by unit cooling towers.

  16. Definition of an auxiliary processor dedicated to real-time operating system kernels

    Science.gov (United States)

    Halang, Wolfgang A.

    1988-01-01

    In order to increase the efficiency of process control data processing, it is necessary to enhance the productivity of real time high level languages and to automate the task administration, because presently 60 percent or more of the applications are still programmed in assembly languages. This may be achieved by migrating apt functions for the support of process control oriented languages into the hardware, i.e., by new architectures. Whereas numerous high level languages have already been defined or realized, there are no investigations yet on hardware assisted implementation of real time features. The requirements to be fulfilled by languages and operating systems in hard real time environment are summarized. A comparison of the most prominent languages, viz. Ada, HAL/S, LTR, Pearl, as well as the real time extensions of FORTRAN and PL/1, reveals how existing languages meet these demands and which features still need to be incorporated to enable the development of reliable software with predictable program behavior, thus making it possible to carry out a technical safety approval. Accordingly, Pearl proved to be the closest match to the mentioned requirements.

  17. CRH2型动车组辅助电源系统故障分析%Fault analysis of auxiliary power system in CRH2 bullet train

    Institute of Scientific and Technical Information of China (English)

    李向超; 王亦军

    2013-01-01

    探讨了300 km速度级CRH2C型动车组辅助电源系统的供电电压、工作原理以及内部构成。针对CRH2C型动车组辅助电源系统的常见故障,分析了故障发生的原因,并提出了有效的应急处理措施。%The supply voltage, working principle and internal structure of auxiliary power supply system in 300 km/h grade CRH2C bullet train are discussed. The common fault causes of auxiliary power supply system in CRH2C bullet train are analyzed. The effective emergent measures for the fault treatment are put forward.

  18. On the Development of Coal Mine Auxiliary Production System%浅谈煤矿辅助生产系统的发展

    Institute of Scientific and Technical Information of China (English)

    姚云华

    2015-01-01

    随着科技的发展和工业化程度的提高,煤矿辅助生产系统也发生了巨大的变化,矿井辅助车间的功能正在逐步弱化,社会化的煤矿服务业正在逐步取代矿井的辅助生产系统。%With the improvement of science and industrialization degree technology development, coal mine production system also occurred in the great changes, the mine auxiliary workshop of function is gradually weakening, the socialization of coal mining services is gradually replacing the mine auxiliary production system.

  19. Controlling the feedwater flow in a BWR. Examples from Forsmark 2; Regleringen av matarvattenfloedet i en BWR. Med exempel fraan Forsmark 2

    Energy Technology Data Exchange (ETDEWEB)

    Bergdahl, Bengt-Goeran; Oguma, Ritsuo (GSE Power Systems AB, Nykoeping (Sweden))

    2009-03-15

    An investigation of the feedwater controller at Forsmark 2 has been performed. The investigation is based on signal analysis of measurement signals recorded during operation of the plant during different tests. The feedwater controller consists of the water level controller, the flow controller and the condenser balance controller. The overall goal of the feedwater control is to maintain constant water level (level controller) in the reactor and at the same time balance the water levels in the two condensers (condenser balance controller) to avoid that one condenser is full of water while the other one is operated with too low level. There is also a feed forward of the difference between steam flow and feedwater flow (flow controller) for each turbine system with the aim to reduce the fluctuation in reactor water level. The relation in strength between the three controllers is such that the level controller is the strongest followed by the condenser balance controller and finally the flow controller. Tests with trip of the feedwater pump and automatic start of the spare pump in each turbine system indicates a fast reduction in reactor water level that is restored after the transient in the control system. The transient in water level is stable without oscillations. However, it takes about 100 s before the reactor water level is restored. The function of the flow controller has been questioned by the authors. It does not take the action that is expected when a disturbance takes place in the difference between steam and feedwater flow. In addition to this principal weakness there is an offset in the feedwater controller output for feedwater flow 22 that reduces the contribution in flow control that is expected during the introduction of a disturbance. This offset should be adjusted during instrument maintenance of the feedwater controller. The PIP parameters for the level controller are gain factors and time constants. These have been evaluated with the aid of

  20. Proposed Auxiliary Boundary Stratigraphic Section and Point (ASSP) for the base of the Ordovician System at Lawson Cove, Utah, USA

    Science.gov (United States)

    Miller, James F.; Evans, Kevin R.; Ethington, Raymond L.; Freeman, Rebecca; Loch, James D.; Repetski, John E.; Ripperdan, Robert; Taylor, John F.

    2016-01-01

    The Global boundary Stratotype Section and Point (GSSP) for the base of the Ordovician System is at the First Appearance Datum (FAD) of the conodont Iapetognathus fluctivagus at Green Point in Newfoundland, Canada. Strata there are typical graptolitic facies that were deposited near the base of the continental slope.We propose establishing an Auxiliary boundary Stratotype Section and Point (ASSP) at the FAD of I. fluctivagus at the Lawson Cove section in the Ibex area of Millard County, Utah, USA. There, strata consist of typical shelly facies limestones that were deposited on a tropical carbonate platform and contain abundant conodonts, trilobites, brachiopods, and other fossil groups. Cambrian and Ordovician strata in this area are ~5300m thick, with the Lawson Cove section spanning 243m in three overlapping segments. Six other measured and studied sections in the area show stratigraphic relationships similar to those at Lawson Cove. Faunas have been used to divide these strata into 14 conodont and 7 trilobite zonal units. The widespread olenid trilobite Jujuyaspis occurs ~90cm above the proposed boundary at Lawson Cove; this genus is generally regarded as earliest Ordovician. Rhynchonelliform and linguliform brachiopods are common to abundant and are useful for correlation. The FAD of Iapetognathus fluctivagus and occurrences of Jujuyaspis and the Lower Ordovician planktonic graptolite Anisograptus matanensis all occur within a 2.4m interval of strata at a nearby section. Non-biological correlation tools include a detailed sequence stratigraphic classification and a detailed carbon-isotope profile. Especially useful for correlation is a positive 13C excursion peak ~15cm below the proposed boundary horizon. All of these correlation tools form an integrated framework that makes the Lawson Cove section especially useful as an ASSP for global correlation of strata with faunas typical of shallow, warm-water, shelly facies.

  1. Optimization of relay protection for a auxiliary power system%厂用电系统继电保护优化

    Institute of Scientific and Technical Information of China (English)

    李子峰

    2015-01-01

    基于对厂用电系统继电保护中存在的配置不完整、后备保护动作时间过长等问题的分析,提出了配置6 kV 母线专用主保护、在低压厂用电系统变压器高压侧增加限时电流速断保护装置、优化后备保护之间配合的方案,并以此对厂用电系统的继电保护配置进行了优化,以600 MW机组为例,进行了保护整定计算,结果表明,优化后的厂用电系统继电保护配置完整,保护范围合理,后备保护动作时间显著缩短。从而,提高了厂用电系统继电保护动作的快速性和厂用电系统运行安全性。%On the basis of analysis on some questions of relay protection in auxiliary power systems,like the imperfection in configuration and the actuation time is too long,a scheme was proposed for relay protection design,such as configuring a specialized main protection for 6 kV busbar,adding a time limited current fast-trip protection on the high-voltage side of low-voltage transformers in auxiliary power system,optimizing the cooperation of reserve protections and then designing the configuration of relay protection in auxiliary power system according to the optimizing rule.Taking a 600 MW unit as the example,settings calculation was carried out.The results proved that the configuration of relay protection in auxiliary power system is integrated perfectly due to the optimization,the coverage of protection is reasonable and the actuation time of reserve protection has been remarkably shortened.Thus,the actuation speed and security of the auxiliary power system are promoted.

  2. Operation and Control of a Direct-Driven PMSG-Based Wind Turbine System with an Auxiliary Parallel Grid-Side Converter

    Directory of Open Access Journals (Sweden)

    Jiawei Chu

    2013-07-01

    Full Text Available In this paper, based on the similarity, in structure and principle, between a grid-connected converter for a direct-driven permanent magnet synchronous generator (D-PMSG and an active power filter (APF, a new D-PMSG-based wind turbine (WT system configuration that includes not only an auxiliary converter in parallel with the grid-side converter, but also a coordinated control strategy, is proposed to enhance the low voltage ride through (LVRT capability and improve power quality. During normal operation, the main grid-side converter maintains the DC-link voltage constant, whereas the auxiliary grid-side converter functions as an APF with harmonic suppression and reactive power compensation to improve the power quality. During grid faults, a hierarchical coordinated control scheme for the generator-side converter, main grid-side converter and auxiliary grid-side converter, depending on the grid voltage sags, is presented to enhance the LVRT capability of the direct-driven PMSG WT. The feasibility and the effectiveness of the proposed system’s topology and hierarchical coordinated control strategy were verified using MATLAB/Simulink simulations.

  3. The Marginalized Auxiliary Particle Filter

    OpenAIRE

    Fritsche, Carsten; Schön, Thomas; Klein, Anja

    2010-01-01

    In this paper we are concerned with nonlinear systems subject to a conditionally linear, Gaussian sub-structure. This structure is often exploited in high-dimensional state estimation problems using the marginalized (aka Rao-Blackwellized) particle filter. The main contribution in the present work is to show how an efficient filter can be derived by exploiting this structure within the auxiliary particle filter. Based on a multisensor aircraft tracking example, the superior performance of the...

  4. 汽车真空辅助制动系统的设计与研究%Design and Research of Automotive Vacuum Auxiliary Braking System

    Institute of Scientific and Technical Information of China (English)

    刘树伟; 郭立新; 郝亮

    2015-01-01

    以汽车紧急制动工况为研究对象,设计和研制了一种汽车真空辅助制动系统,该系统主要包括机械执行机构、制动吸盘、真空系统、弹射收起系统、控制系统五个部分。对该系统进行了理论分析和实验研究,结果表明,该系统可显著提高汽车制动效能,可有效缩短汽车紧急制动时的制动距离,从而有效降低交通事故的发生概率并降低交通事故的严重程度。%An automotive vacuum auxiliary braking system was designed when the driver urgently braked the automobile.The system mainly contained five parts,such as mechanical actuator,braking sucker,vacuum system,ejection retracting system,the control system and so on.The vacuum auxiliary braking system could increase significantly the braking efficiency and shorten the braking distance of automobile emergency braking.After the theoretical analysis and the experimental research,the sys-tem will reduce effectively the probability and the damage degree of traffic accidents.

  5. Ethanolamine properties and use for feedwater pH control: A pressurized water reactor case study

    International Nuclear Information System (INIS)

    Ethanolamine (ETA) as a feedwater pH control additive has been recently used to minimize corrosion of secondary water components in the nuclear power industry pressurized water reactors (PWRs). The use of ETA is compared with ammonia. Relative volatility effects on various parts of the system are analyzed and chemistry changes are presented. Materials of construction and the use of existing plant equipment for ETA service are discussed. Properties of ETA as well as safety, storage and handling issues are compared with ammonia. Health d aquatic toxicity are reviewed. warnings, safety, handling guidelines, biodegradability an Diablo Canyon Power Plant used ammonia for pH control from 1985 until a change over to ETA in 1993/1994. Full flow condensate polishers that are required to protect the plant from saltwater cooling incursions limit the amount of pH additive. Iron levels in the secondary water systems are compared before and after changing to ETA and replacement of corrosion-susceptible piping. Iron reduction benefits are assessed along with other effects on the feedwater nozzles, low pressure turbine, polisher resin capacity and polisher regeneration system

  6. Changes in feedwater organic matter concentrations based on intake type and pretreatment processes at SWRO facilities, Red Sea, Saudi Arabia

    KAUST Repository

    Dehwah, Abdullah

    2015-03-01

    Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface intake systems or placement of the intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An intake placed at a depth of 9. m below the surface was found to have limited impact on improving water quality compared to a surface intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.

  7. Auxiliary Deep Generative Models

    DEFF Research Database (Denmark)

    Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae;

    2016-01-01

    Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave...... the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge...... faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST (0.96%), SVHN (16.61%) and NORB (9.40%) datasets....

  8. Performance evaluation of a state-of-the-art solar air-heating system with auxiliary heat pump. Final report, 1 October 1978-30 September 1979

    Energy Technology Data Exchange (ETDEWEB)

    Karaki, S.; Brisbane, T.E.; Waterbury, S.S.; Lantz, T.G.

    1980-01-01

    The solar heating system in Solar House II, evaluated during the heating season of 1978-1979, consists of 57.9 m/sup 2/ of Solaron Series 3000 Collectors, 10.3 m/sup 3/ of pebble bed storage, domestic water preheating capability and a Carrier air-to-air heat pump as an auxiliary heater. Although the control subsystem was specially constructed to facilitate experimental changes and data reduction, the balance of the solar system was assembled with off-the-shelf components. Descriptions of the building and the system, modes of system operation, the data acquisition system, data processing, and performance - thermal, collector, storage, and heat pump - are included. (MHR)

  9. Methodology for carrying out energy diagnosis in auxiliaries systems in thermal electrical central stations; Metodologia para realizar un diagnostico energetico en sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Nebradt Garcia, Jesus [Comision Federal de Electricidad (CFE), Mexico, D. F. (Mexico); Rojas Hidalgo, Ismael; Huante Perez, Liborio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    One of the potential areas for energy saving in Central Electric Power Plants are the auxiliaries system, so as to based in a preliminary energy diagnosis and considering that energy saving measures would be taken, going from the instrumentation, operational changes in equipment, as well as in using velocity variators in motors, it turns out to be that the energy consumption of auxiliaries at 75% load in a 150 MW thermal power plant varies from 3% to 4% and for the case of a 350 MW power plant the energy consumption of the auxiliaries represents 2 to 3.5%. Nowadays this consumption are above 6%. Considering that the country has 40 units with capacities varying from 150 to 350 MW, the economical and the fuel saving would be substantial. This paper will present a summary of the methodology to be used to carry out this type of projects. [Espanol] Una de las areas potenciales de ahorro de energia en centrales termoelectricas son los sistemas auxiliares, de tal manera que basados en un diagnostico energetico preliminar y considerando que se aplicarian las medidas de ahorro de energia que van desde la instrumentacion, cambios operativos en equipos, asi como el uso de variadores de velocidad en motores, se tienen que los consumos de auxiliares para un 75% de carga en una central termoelectrica de 150 MW varian desde un 3% hasta un 4% y para el caso de una central termoelectrica de 350 MW, el consumo de auxiliares representa del 2 al 3.5%. Hoy en dia dichos consumos estan por encima del 6%. Si consideramos que el pais cuenta con 40 unidades que varian desde 150 MW hasta 350 MW, entonces los ahorros economicos y de combustible serian impactantes. La presente ponencia mostrara un resumen de la metodologia a emplear para la realizacion de este tipo de proyectos.

  10. Optimizationin Operational Analysis of Auxiliary Steam System in Thermal Power Plant%火力发电厂辅汽系统优化运行分析

    Institute of Scientific and Technical Information of China (English)

    王乃军; 白秀春; 王俊俊

    2015-01-01

    For choosing different steam source for the auxiliary steam system in Inner Mongolia Daihai Electric Power Generation Co.,Ltd., carry on the quantitative analysis to the influence of the unit efficiency, the result is the most economical when choosing No.4 extraction steam of second unit supplying, while slightly economical as using second unit cold reheater as first unit. According to the results of the analysis, it provides a theoretical basis and guidance for selecting the source of auxiliary steam in power plants, so as to achieve the purpose of saving energy and reducing consumption, improve the operation efficiency. At the same time, based on the actual operating mode, unit start-up and shutdown, accident conditions, combined with different seasons and temperature, auxiliary steam consumption, it proposes operation precautions.%对内蒙古岱海发电有限责任公司辅助蒸汽系统选择不同供汽汽源时,机组运行经济性受到的影响进行了定量分析,认为由二期机组四段抽汽供汽经济性最优,由二期机组冷段再热蒸汽供汽的经济性略优于由一期机组冷段再热蒸汽供汽。并结合机组实际运行方式、机组启停方式及机组发生事故时的运行情况等,根据不同季节环境温度及各辅汽用户用汽量情况,提出辅汽系统优化运行注意事项。

  11. Electric power plant technology. Generators, transformers, auxiliary installations, protective systems. Lecture notes. 5. rev. ed.; Elektrische Kraftwerkstechnik. Generatoren, Transformatoren, Eigenbedarfsanlagen, Schutzeinrichtungen. Vorlesungsskript

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Ulrich

    2009-07-01

    The lecture series on electric power plant engineering was initiated in 1969 by Prof. Helmut Schaefer, founder of the then department of power economy and power plant engineering. The lecture series was continuously updated in its contents and didactic approach, e.g. by integrating innovative power generation concepts like micro cogeneration plants and fuel cell systems. The focus is on the fundamentals and function of generators, main transformers, auxiliary installations and protective systems in power plant. Apart from the electrotechnical aspects, also aspects of mechanical engineering are gone into. Also discussed are energy conversion concepts fo renewable power generation plants like wind turbines and PV systems. This is the 5th, completely revised edition. It addresses primarily attendants of the lectures but may also serve as a textbook and reference manual for interested experts.

  12. Fuzzy Logic Approach to Diagnosis of Feedwater Heater Performance Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yeon Kwan; Kim, Hyeon Min; Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Sang, Seok Yoon [Engineering and Technical Center, Korea Hydro, Daejeon (Korea, Republic of)

    2014-08-15

    Since failure in, damage to, and performance degradation of power generation components in operation under harsh environment of high pressure and high temperature may cause both economic and human loss at power plants, highly reliable operation and control of these components are necessary. Therefore, a systematic method of diagnosing the condition of these components in its early stages is required. There have been many researches related to the diagnosis of these components, but our group developed an approach using a regression model and diagnosis table, specializing in diagnosis relating to thermal efficiency degradation of power plant. However, there was a difficulty in applying the method using the regression model to power plants with different operating conditions because the model was sensitive to value. In case of the method that uses diagnosis table, it was difficult to find the level at which each performance degradation factor had an effect on the components. Therefore, fuzzy logic was introduced in order to diagnose performance degradation using both qualitative and quantitative results obtained from the components' operation data. The model makes performance degradation assessment using various performance degradation variables according to the input rule constructed based on fuzzy logic. The purpose of the model is to help the operator diagnose performance degradation of components of power plants. This paper makes an analysis of power plant feedwater heater by using fuzzy logic. Feedwater heater is one of the core components that regulate life-cycle of a power plant. Performance degradation has a direct effect on power generation efficiency. It is not easy to observe performance degradation of feedwater heater. However, on the other hand, troubles such as tube leakage may bring simultaneous damage to the tube bundle and therefore it is the object of concern in economic aspect. This study explains the process of diagnosing and verifying typical

  13. The chemistry of feedwater for boiling-water and pressurized-water reactors

    International Nuclear Information System (INIS)

    In a nuclear power plant the purity of the feedwater depends largely on whether a condensate polishing plant is provided, whether the loop is conditioned and on the presence of corrosion products originating in the materials from which the loop is made. The feedwater specification depends on the type of steam generator used. The article defines the characteristic parameters of a condensate polishing plant (CPP), such as the 'degree of polishing' and 'practical exchange capacity of the resins' and indicates how they can be determined. In pressurized-water reactors (PWR) the feedwater is normally conditioned with hydrazine. Measurements are quoted to demonstrate that, in contrast to conventional plants, the point of injection is immaterial as regards the copper content of the feedwater. Moreover, the iron content of the feedwater of a PWR can be reduced by using cyclic amines. The feedwater chemistry of a BWR is discussed by referring to oxygen, iron and copper measurements. The authors show that in loops in which the feed-heater condensate is pumped forwards and where a feedwater tank is provided, the stipulated purity of the feedwater can be attained by suitable measures (such as mechanical filtration, prevention of erosion-corrosion, and so on). (Auth.)

  14. Analysis and Comparing of Urban Rail Locomotive Auxiliary System AC Power Supply Mode%城轨列车辅助系统交流供电方式的分析与比较

    Institute of Scientific and Technical Information of China (English)

    阎纯洁

    2015-01-01

    Through analyzing the urban rail locomotive auxiliary system AC power system supply mode, comparing the ad-vantages and disadvantages of general power supply mode and individual supply mode, prove accordance to urban rail auxil-iary system AC power supply mode selection.%通过对城轨列车辅助系统交流供电方式进行分析,比较集中供电方式和分散供电方式的各自优劣,为城轨列车辅助系统交流供电供电方式选型提供依据。

  15. Sectional replacement of high pressure feedwater heater tubing

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, J.A.; Bowes, P.D. [TransAlta Utilities Corp., Duffield, Alberta (Canada). Plant Engineering Services

    1994-12-31

    TransAlta Utilities is a Canadian Corporation which owns and operates the coal fired Sundance Generating Station located in central Alberta. Sundance is fitted with vertical channel down, carbon steel tubed, high pressure feedwater heaters. The primary mode of failure of these HP feedwater heaters on the six generating units is steam inlet area tube erosion and vibration damage. This damage is initiated with the deterioration of the desuperheating inlet shroud and backing plate, primarily due to thermal fatigue, thus allowing direct impingement of high velocity steam and entrained condensate upon the tubing. Topics discussed are: review of the design and conditions of the heater which allowed re-conditioning; cutting, lifting and supporting of the shell at an elevation sufficient to allow free access of the entire desuperheating zone; damage observed within the desuperheating and drains cooler zones; bundle reconditioning through damage tube section replacement and support plate repair techniques; design/installation of the desuperheating, drains-cooling zone shrouds and backing plates; benefits that this type of approach may offer; conclusions.

  16. Nuclear reactors with auxiliary boiler circuit

    International Nuclear Information System (INIS)

    A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

  17. Auxiliary power unit for moving a vehicle

    Science.gov (United States)

    Akasam, Sivaprasad; Johnson, Kris W.; Johnson, Matthew D.; Slone, Larry M.; Welter, James Milton

    2009-02-03

    A power system is provided having at least one traction device and a primary power source configured to power the at least one traction device. In addition, the power system includes an auxiliary power source also configured to power the at least one traction device.

  18. Window-mounted auxiliary solar heater

    Science.gov (United States)

    Anthony, K. G.; Herndon, E. P.

    1977-01-01

    System uses hot-air collectors, no thermal storage, and fan with thermostat switches. At cost of heating efficiency, unit could be manufactured and sold at price allowing immediate entry to market as auxiliary heating system. Its simplicity allows homeowner installation, and maintenance is minimal.

  19. Sensitivity Analysis of Core Damage by Loss of Auxiliary Feed Water during the Extended Loss of All AC Power

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Woo Jae; Chung, Soon Il; Hwang, Su Hyun; Lee, Kyung Jin; Lee, Byung Chul [FNC Tech., Yongin (Korea, Republic of); Yun, Duk Joo; Lee, Seung Chan [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2015-10-15

    In this study, the reactor core damage time for OPR1000 type Nuclear Power Plant (NPP) was analyzed to develop a strategy to handle ELAP and to apply to the EOP. The reactor core damage time in the ELAP condition was calculated according to the time of Auxiliary Feedwater (AFW) loss. Fukushima accident was caused by long hours of Station Black Out (SBO) caused by natural disaster beyond Design Based Accident (DBA) criteria. It led to the reactor core damage. After the accident, the regulatory authorities of each country (Japan, US, EU, IAEA, and etc.) recommended developing the necessary systems and strategies in order to cover up the Extended Loss of All AC Power (ELAP) such as one occurred in the Fukushima accident. And the need of procedure or guideline to cope with ELAP has been raised through the stress test for Wolsong Nuclear Power Plant unit 1. Current Emergency Operating Procedures (EOP) used in domestic nuclear power plant are seemed to be insufficient to cope with ELAP. Therefore, it has been required to be improved. As the result, the time of AFW loss in the ELAP condition influences greatly on core damage time.

  20. 'Better feedwater quality through heat exchange equipment renovation'

    Energy Technology Data Exchange (ETDEWEB)

    Pouzenc, C. [ALSTOM Power Heat Exchange (France)

    2002-07-01

    In a fossil-fired or nuclear steam power plant, the water secondary circuit is a critical part of its thermodynamic cycle, as it achieves conditioning, pressurizing and heating of the condensate to match the conditions required at the steam generator inlet. Furthermore, the power plant electrical output and efficiency depend on availability and performances of each component of this secondary circuit from the condenser to the steam generator. Erosion and corrosion phenomena are at the origin of most significant failures in these components and related interconnecting systems. Feedwater chemistry is, together with the selection of materials and optimization of fluid velocities, one of the key levers to protect, as efficiently as possible, the components of the water secondary. (authors)

  1. Loss of a main feedwater pump test at 100% power simulation using Korean standard nuclear plant analyzer (KSNPA)

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Won Sang; Kim, Shin Whan; Sung, Kang Sik; Seo, Jong Tae; Lee, Sang Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-07-01

    The Loss of a Main Feedwater Pump test at 100% Power for YGN 4 was simulated in order to verify and validate the KSNPA. The comparison of the test data with the KSNPA prediction results showed reasonable agreement in the trends of the major plant parameters. All plant control systems including NSSS and T/G control systems are properly actuated and stabilized the plant conditions to a new steady state conditions in the KSNPA. From the comparison results, the KSNPA showed its capability to simulate the LOMFP event for the KOrean Standard Nuclear Power Plant.

  2. Heat exchanger inventory cost optimization for power cycles with one feedwater heater

    International Nuclear Information System (INIS)

    Highlights: • Cost optimization of heat exchanger inventory in power cycles is investigated. • Analysis for an endoreversible power cycle with an open feedwater heater is shown. • Different constraints on the power cycle are investigated. • The constant heat addition scenario resulted in the lowest value of the cost function. - Abstract: Cost optimization of heat exchanger inventory in power cycles with one open feedwater heater is undertaken. In this regard, thermoeconomic analysis for an endoreversible power cycle with an open feedwater heater is shown. The scenarios of constant heat rejection and addition rates, power as well as rate of heat transfer in the open feedwater heater are studied. All cost functions displayed minima with respect to the high-side absolute temperature ratio (θ1). In this case, the effect of the Carnot temperature ratio (Φ1), absolute temperature ratio (ξ) and the phase-change absolute temperature ratio for the feedwater heater (Φ2) are qualitatively the same. Furthermore, the constant heat addition scenario resulted in the lowest value of the cost function. For variation of all cost functions, the smaller the value of the phase-change absolute temperature ratio for the feedwater heater (Φ2), lower the cost at the minima. As feedwater heater to hot end unit cost ratio decreases, the minimum total conductance required increases

  3. VRV auxiliary air conditioning system for the BMW Group Pavillon, Munich; VRV-Zusatzklimaanlage fuer den BMW Group Pavillon in Muenchen

    Energy Technology Data Exchange (ETDEWEB)

    Pfeiffenberger, U. [Ingenieurgesellschaft Pfeiffenberger mbH, Neu-Isenburg (Germany); Zeller, A. [Daikin Airconditioning Germany GmbH, Unterhaching (Germany)

    2004-07-01

    The cooling capacity of the air conditioning system of this fully glazed, representative exhibition pavillong was increased. The auxiliary system was to meet a number of boundary conditions, e.g. conservation of a historical building, integration of the new components in the existing building, thermal comfort, optical attractivity. In order to ensure high thermal efficiency, compact size and energy conservation, a VRV inverter system was chosen. The fundamentals of dimensioning, the boundary conditions on the building side, and the technical systems are described, and preliminary operating experience is presented. (orig.) [German] Fuer einen vollverglasten, repraesentativen Ausstellungs-Pavillon musste die vorhandene Kuehl-Kapazitaet der klimatechnischen Anlage erhoeht werden. Die Zusatz-Installation sollte eine Vielzahl von Randbedingungen, wie z. B. Denkmalschutz des Gebaeudes, Integration der Bauteile in die vorhandenen Decken und Verkleidungen, Einhaltung der Komfortbedingungen, sowie ansprechendes optisches Aeusseres der sichtbaren Installationen erfuellen. Wegen der grossen Kaelteleistung bei geringstmoeglichem Platzbedarf und einer moeglichst energieguenstigen Betriebsweise wurde ein VRV-Inverter-System ausgewaehlt. Die Bemessungsgrundlagen, die gebaeudeseitigen Randbedingungen sowie die technische Loesung werden beschrieben und die ersten Betriebserfahrungen wiedergegeben. (orig.)

  4. Comparative Studies of the Operation Method of Solar Energy Water Heating System with Auxiliary Heat Pump Heater%热泵辅助供热太阳能热水系统运行模式对比分析

    Institute of Scientific and Technical Information of China (English)

    林辩启; 罗会龙; 王浩; 田盼雨

    2015-01-01

    太阳能热水系统与热泵辅助供热合理结合可取长补短,有效降低建筑能耗。简要概述了空气源热泵、水源热泵、地源热泵辅助供热太阳能热水系统的结构形式及其运行模式。在此基础上,对比分析了热泵辅助供热太阳能热水系统各种典型运行模式的特点及其适用的应用环境。%The appropriate combination of solar water heating system and heat pump auxiliary heating is an effective way to reduce the building energy consumption. The structure and operation method of solar water heating system with different auxiliary heating, such as air-source heat pump, water-source heat pump, and soil-source heat pump, were introduced briefly. The characteristics of all kinds of solar water heating system with auxiliary heating were compared and analyzed. The suitable application environment of solar water heating system with auxiliary heating was also presented.

  5. Mining Reclamation Auxiliary Information System Based on GIS%基于GIS的矿区土地复垦辅助信息系统

    Institute of Scientific and Technical Information of China (English)

    许冬; 吴侃; 杨永均

    2012-01-01

    为满足矿区土地复垦方案编制的实际需要,提高矿区土地复垦的信息化水平,重点解决土地损毁预测、土地复垦适宜性评价、工程量计算和土地复垦相关图件制作等问题,应用GIS、RS和三维数据可视化等技术,实现矿区土地复垦辅助信息系统的设计与开发;借助ArcGIS Engine 、Visual Studio 2008 、ENVI/IDL,将GIS、RS、数学模型和空间数据库等技术相结合,构建了具有较强科学性和通用性,集土地损毁预测、土地复垦评价、规划、监督检查等功能于一体的矿区土地复垦辅助信息系统;通过构建矿区土地复垦辅助信息系统,有助于提高规划的效率和科学性,为我国矿区土地复垦的信息化提供借鉴和参考.%In order to meet the needs of mine land reclamation program development and improve the level of mine land reclamation information technology,this paper focuses on solving land damage prediction,land reclamation suitability assessment,engineering calculation,and land reclamation maps production. The geographic information system,remote sensing and 3D data visualization technology are applied to achieve mining reclamation auxiliary information system. With ArcGIS Engine,Visual Studio 2008,ENVI/IDL,we combined geographic information system,remote sensing and mathematical model with spatial database technology to build a set of land reclamation ancillary information system with strong scientific and versatility performance and functions of land damage prediction,land reclamation evaluation,planning,supervision and inspection. Through constructing a mining reclamation auxiliary information system,the planning efficiency and scientificity are improved,thus providing reference for information technology of mine land reclamation.

  6. Dynamic characteristics of a VK-50 reactor operating under conditions of the loss of a normal feedwater flow

    Science.gov (United States)

    Semidotskiy, I. I.; Kurskiy, A. S.

    2013-12-01

    The paper describes the conditions of the ATWS type with virtually complete cessation of the feed-water flow at the operating power level of a reactor of the VK-50 type. Under these conditions, the role of spatial kinetics in the system of feedback between thermohydraulic and nuclear processes with bulk boiling of the coolant in the reactor core is clearly seen. This feature determines the specific character of experimental data obtained and the suitability of their use for verification of the associated codes used for calculating water-water reactors.

  7. Control of Auxiliary System for USC Steam Turbines%超超临界汽轮机辅助系统的控制

    Institute of Scientific and Technical Information of China (English)

    李刚

    2016-01-01

    介绍了超超临界汽轮机辅助系统的控制策略,包括本体疏水、抽汽逆止阀、汽封及油系统四个方面的内容。通过详细分析各子系统的控制特点,论证了超超临界汽轮机辅助系统控制的独特性和先进性。掌握这种控制策略,可为新系统开发提供理论参照。%The control strategy including turbine drains ,extraction non‐return valves ,gland seal and oil system for auxiliary system of USC steam turbines is presented .Based on analysis of the control characteristics of each subsystem ,the unique features and advances in this system are demonstrated .The strategy shall be regarded as theoretical reference for developing the new system of USC steam turbines .

  8. MATLAB GUI Design of Auxiliary Teaching System for Multivariate Statistics Course%多元统计课程教辅系统的 MATLAB GUI 设计

    Institute of Scientific and Technical Information of China (English)

    周志刚; 陈丽红

    2013-01-01

      针对目前多元统计方法课程教学重点内容涉及大量数据的统计处理难以在课堂上现场演示,学生接受多元统计知识感觉困难、枯燥的问题,文章利用 MATLAB GUI (Graphical User Interfaces,GUI)设计了一个多元统计方法课程教学辅助系统,用于多元统计方法课程的教学和学生实验。教学辅助系统的设计从教学层面和系统设计的技术层面进行了探讨,设计的教学辅助系统具有使用较方便、良好交互性和可扩展性的特点。同时 MATLAB GUI 开发环境开发出的教辅系统便于学生做二次开发,可以提高学生动手实践能力及多元统计方法课程的教学质量。%In view of the problems in the traditional multivariate statistics course teaching,which contain it is difficult to demonstrate in class about principle of key teaching content and statistic treatment of large quantities of data,students feel difficult to receive multiple sta-tistical knowledge,a multivariate statistics course teaching auxiliary system is designed by using MATLAB GUI (Graphical User Inter-faces,GUI). The system is used for multivariate statistical methods course teaching and students' experiment. Auxiliary teaching system was discussed from two aspects about teaching and technology and has advantages of convenient use,good interactivity and expansibility. At the same time,this system also facilitate students to do the secondary development,can improve students' practical ability and multiva-riate statistical methods course teaching quality.

  9. 发电厂高压厂用电系统的安全与稳定性研究%Study on Security and Stability of High Voltage Auxiliary Power System of Power Plant

    Institute of Scientific and Technical Information of China (English)

    黄亚军; 杨开黎; 姜平

    2012-01-01

    The supercritical capacity units are popularized in China now, the security and stability of high voltage auxiliary power system of power plant need to be taken into account when designing the auxiliary power system. This paper discusses some detailed questions of designing the auxiliary power system from four aspects of the voltage level choice, choosing neutral ground of auxiliary power system, relay protection, integration multi-function relay protection applying, electrical source quick switch device. The purpose of the paper is to provide basis for improving the security and stability of high voltage auxiliary power system of supercritical capacity thermal power plant, nuclear power plant and hydro-power station.%随着超临界大容量机组的普及,发电厂高压厂用电系统在设计时需要考虑其安全与稳定性方面的问题.本文分别从厂用电电压等级选择、厂用电系统中性点接地方式的选择、厂用电的继电保护、集成化的多功能综合继电保护装置的应用及厂用电电源快切装置发展等方面,论述了厂用电系统优化设计时需要注意的一些细节问题,为提高大型火电、核电、水电发电厂厂用电系统的安全与稳定性奠定了基础.

  10. Study of thermohydraulic characteristics of upgraded feedwater collector in PGV-440 steam generator

    Energy Technology Data Exchange (ETDEWEB)

    Tarankov, G.A.; Trunov, N.B.; Titov, V.F. [OKB Gidropress (Russian Federation); Urbansky, V.V. [Rovno NPP (Ukraine); Lenkei, I.; Notarosh, M. [Paks NPP (Hungary)

    1995-12-31

    Reconstruction of feedwater distribution collector was performed at unit 1 of Rowno NPP. Main results of measurements of temperatures in water volume, reparation characteristics and impurities distribution are presented. Analysis of tests results and design criteria is given. (orig.).

  11. Pre-test calculations of SPES experiment - a loss of main feedwater transient

    International Nuclear Information System (INIS)

    Results of a pre-test calculation of international standard experiment ISP-22 SPES are shown in this paper. SPES facility represents a model of three-loop PWR power plant which was used to perform an experimental loss of main feedwater transient with emergency feedwater delayed. calculation was performed by RELAP5/MOD2/36.1 computer code which we had converted to VAX computers. (author)

  12. 海上平台采油树辅助液压系统研究%Study of the christmas tree auxiliary hydraulic control system on offshore platform

    Institute of Scientific and Technical Information of China (English)

    陈肇日; 苟潮洋

    2011-01-01

    海上平台采油树钢丝作业过程中,为了防止采油树液控主阀意外关闭而切断钢丝,目前采用的是给液控主阀戴帽的方法,此方法存在很大的安全隐患.设计了采油树辅助液压系统,在钢丝作业过程中采用双液压源控制采油树液控主阀,提高了钢丝作业过程的安全性.%At present, the valve cap is used to prevent the wire line from cut off due to unexpected close of hydraulic master valve during the christ-mas tree wire line operation on offshore platform. This method has the potential safety hazard. Therefore,a set of auxiliary hydraulic control system has been designed to keep the master valve o-pening by using double hydraulic source during the wire line operation, so as to improve the safety of wire line operation.

  13. IOS Auxiliary Color Recognition System for the Color Blind%面向色盲人群的IOS色彩辅助识别系统

    Institute of Scientific and Technical Information of China (English)

    郭华峰; 范渊; 洪年松; 陈兵国

    2013-01-01

    Color blind is a defect which can't perceive part or all colors correctly. The lack of color discrimination ability brings a lot of inconvenience to color blind's work, study and life. In this article, an auxiliary color recognition system based on IOS is de-signed and implemented, which can convert colors of IOS pictures to colors that color blind can recognize, which will enhance life ex-perience of color blind.%色盲是一种无法正确感知部分或全部颜色的缺陷。由于色盲辨色能力的不足,因此给患者的工作、学习和生活带来了很多的不便。设计并实现了一个基于IOS的色彩辅助识别系统,把IOS照片中的色彩转换成色盲人群可以识别的颜色,从而提高了色盲人群的生活体验。

  14. Economic Optimization of Solar-Electric Auxiliary Heating System%太阳能-电辅热供暖系统的经济优化

    Institute of Scientific and Technical Information of China (English)

    程磊; 田琦

    2011-01-01

    集热器面积的选择是太阳能供暖系统设计的关键,本文对太阳能一电辅热供暖系统进行了技术经济分析,建立了系统费用年值与集热器面积函数关系的数学模型,分析探讨了使费用年值最小的集热器面积的计算方法。并以太原为例(100m^2住宅)逐日进行了计算,结果表明当集热器面积为21.34m^2,整个系统的费用年值最小;整个采暖季的太阳能保证率为60.24%。%Collector area is the key to a solar heating system while designing. In this paper, the technical-economic analysis of a solar-electric auxiliary heating system was carried. The mathematical model of the functional relation between the annual system cost and the collector area was established, and the calculating method of collector area based on the minimum annual cost was discussed. Taking a 100m^2 residential in Taiyuan as an example, the result of daily calculation shows that the annual cost of the system is minimum when the collector area is 21.34m^2. The solar fraction of the whole heating season is up to 60.2%.

  15. Auxiliary nRules of Quantum Mechanics

    OpenAIRE

    Mould, Richard A

    2005-01-01

    Standard quantum mechanics makes use of four auxiliary rules that allow the Schrodinger solutions to be related to laboratory experience, such as the Born rule that connects square modulus to probability. These rules (here called the sRules) lead to some unacceptable results. They do not allow the primary observer to be part of the system. They do not allow individual observations (as opposed to ensembles) to be part of the system. They make a fundamental distinction between microscopic and m...

  16. Decommissioning of the ASTRA research reactor: Dismantling the auxiliary systems and clearance and reuse of the buildings

    Directory of Open Access Journals (Sweden)

    Meyer Franz

    2008-01-01

    Full Text Available The paper presents work performed in the last phase of the decommissioning of the ASTRA research reactor at the Austrian Research Centers Seibersdorf. Dismantling the pump room installations and the ventilation system, as well as the clearance of the buildings is described. Some conclusions and summary data regarding the timetable, material management, and the cost of the entire project are also presented.

  17. Connection of auxiliary power supply to the power plant's main instrumentation and control system by way of IEC 61850; Anbindung des elektrischen Kraftwerks-Eigenbedarfs an die Hauptleittechnik mittels IEC 61850

    Energy Technology Data Exchange (ETDEWEB)

    Ciuches, Joerg [RWE Technology GmbH, Essen (Germany). Technical Project Management Project BoA 2 and 3; Wittner, Stephan [RWE Technology GmbH, Essen (Germany). Electrical Engineering

    2010-07-01

    Based on the positive experience with the integration of control and signalling of the auxiliary power supply switchgear into the I and C system SPPA-T-3000 of Siemens by way of the IEC 61850 protocol in the Neurath power plant F/G project, the concept was further advanced for the power plant new build projects of the Westfalen power plant at Hamm and the Eemshaven power station in the Netherlands. The development aimed to integrate all other components of auxiliary power supply, such as transformers, battery systems as well as rectifiers and inverters, directly into the main I and C system on the basis of the IEC 61850 protocol, apart from the medium-voltage and low-voltage switchgear. (orig.)

  18. Research of auxiliary energy storage system in hybrid electric vehicles%混合电动汽车辅助储能系统的研究

    Institute of Scientific and Technical Information of China (English)

    武琼; 滕青芳

    2013-01-01

    针对混合电动汽车在城市交通中频繁加速减速的特点,设计了基于超级电容储能的电动汽车辅助储能系统,选择两相交错式半桥拓扑双向DC/DC变换器作为超级电容的充放电电路.重点设计双向DC/DC变换器对超级电容的充放电控制,采用平均电流控制的两个电感电流内环和一个电压外环的控制策略,并对电动汽车辅助储能系统进行了Simulink仿真,从而有效验证了超级电容在电动汽车中应用的优势.%Hybrid electric vehicles have the characteristics of frequent acceleration and slowdown in urban traffic. A bi-directional DC-DC converter in the super-capacitor energy system was designed. A topology for bidirectional interleaved DC/DC converter was used in the super-capacitor energy system. The design of control loop of charge mode and discharge mode for the super-capacitor was emphasized, using two inner inductor current loop and one outer voltage loop of average-current-controlled. The auxiliary energy storage system for hybrid electric vehicles was simulated and the advantage of super-capacitor in hybrid electric vehicles could be effectively verified.

  19. Infrared Camera Characterization of Bi-Propellant Reaction Control Engines during Auxiliary Propulsion Systems Tests at NASA's White Sands Test Facility in Las Cruces, New Mexico

    Science.gov (United States)

    Holleman, Elizabeth; Sharp, David; Sheller, Richard; Styron, Jason

    2007-01-01

    This paper describes the application of a FUR Systems A40M infrared (IR) digital camera for thermal monitoring of a Liquid Oxygen (LOX) and Ethanol bi-propellant Reaction Control Engine (RCE) during Auxiliary Propulsion System (APS) testing at the National Aeronautics & Space Administration's (NASA) White Sands Test Facility (WSTF) near Las Cruces, New Mexico. Typically, NASA has relied mostly on the use of ThermoCouples (TC) for this type of thermal monitoring due to the variability of constraints required to accurately map rapidly changing temperatures from ambient to glowing hot chamber material. Obtaining accurate real-time temperatures in the JR spectrum is made even more elusive by the changing emissivity of the chamber material as it begins to glow. The parameters evaluated prior to APS testing included: (1) remote operation of the A40M camera using fiber optic Firewire signal sender and receiver units; (2) operation of the camera inside a Pelco explosion proof enclosure with a germanium window; (3) remote analog signal display for real-time monitoring; (4) remote digital data acquisition of the A40M's sensor information using FUR's ThermaCAM Researcher Pro 2.8 software; and (5) overall reliability of the system. An initial characterization report was prepared after the A40M characterization tests at Marshall Space Flight Center (MSFC) to document controlled heat source comparisons to calibrated TCs. Summary IR digital data recorded from WSTF's APS testing is included within this document along with findings, lessons learned, and recommendations for further usage as a monitoring tool for the development of rocket engines.

  20. Auxiliary services offered to operator of transmissive system - the primary and secondary regulation of active capacity in ENO, o.z

    International Nuclear Information System (INIS)

    The change of outmoded analogue regulators of turbogenerators of Novaky Thermal Power Plant (TG ENO) B1 and B2 to new digital assigned the basic condition for fulfilment of strict rules for providing of auxiliary services - of primary and secondary regulation of active capacity and regulation of turns. The paper deals with technical and program sources for realisation of marked auxiliary services on the level of direct regulation of bloc, with fulfilment and evaluating of auxiliary services according to valid norm PNE 34-01/2002 in condensation and power take off operation of blocks after realisation of extraction of heat in hot water from ENO B. The paper argues, that regulation attributes of block - regulation zone of active capacity for primary and secondary regulation as like as the parameters of these regulations have been not changed by power take off operation. (author)

  1. WMO Selected, Supplemenatary, Auxiliary Ships

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Meteorological Organization International List of Selected, Supplementary and Auxiliary Ships, recognized as Publication 47. 1973-1998 editions, gathered from...

  2. Replacement of electrical protection of generation (main generator, main transformer and auxiliary transformers) and new associated monitoring system

    International Nuclear Information System (INIS)

    The replacement of the electrical protection of generation is a technological quantum leap, since moving from an analog system (known by) (all, intuitive and visual) to a digital (integrates the hardware on a single computer, much more powerful and programmable). The keys to overcoming the challenge are know to manage the technological leap, the operational limitations of plant (keep operating the)preferred sources of energy) and make a good design (including a review independent of the configuration of the relays, taking into account the experience (operational available).

  3. Economizer water-wall damages initiated by feedwater impurities

    Directory of Open Access Journals (Sweden)

    Vidojković Sonja M.

    2014-01-01

    Full Text Available The main causes of efficiency loss in thermal power plants are boiler tube failures that diminish unit reliability and availability, and raise the cost of the electric energy. For that reason, regular examination of boiler tubes is indispensable measure for prevention future malfunctions of power units. Microscopic examination of economizer inner wall microstructure, analysis of chemical composition of deposit using x-ray diffraction (XRD and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS has been performed in a subcritical power plant. Stress corrosion cracking, pitting corrosion, destroyed protective magnetite layer, presence of magnetite and hematite in deposit and corrosive impurities within the cracks were indicated the effect of inadequate quality of feedwater that can not entirely ensure reliable operation of the boiler. It may be stated that maintenance of present boiler does not provide its reliable operation. Extensive chemical control of water/steam cycle was recommended. [Projekat Ministartsva nauke Republike Srbije, br. III 43009 i br. III 45012

  4. Investigations in the modelling and control of a medium voltage hybrid inverter system that uses a low voltage /low power rated auxiliary current source inverter

    OpenAIRE

    Papadopoulos, Savvas; Rashed, Mohamed; Klumpner, Christian; Wheeler, Patrick

    2016-01-01

    Hybrid converters consist of a main inverter processing the bulk of the power with poor waveform performance and a fast and versatile auxiliary inverter to correct the distortion. In this paper, the main converter is a medium voltage NPC inverter and the auxiliary inverter is a low-voltage and low-current rated current source inverter (CSI), with series capacitor being used to minimize the CSI voltage stress. The result is a high output current quality which is obtained with a very low switch...

  5. Design of Lean Shipbuilding Auxiliary System%精益造船辅助系统的设计

    Institute of Scientific and Technical Information of China (English)

    汪德庆; 李宗骍; 赵李飞; 尚鑫; 王玉涛; 曹晶

    2013-01-01

    本文在总结精益制造的发展与应用基础上,通过企业的实地调研分析,结合管理和生产诸多方面的因素,针对当前企业内用于套料的材料信息管理,与优化套料,设计与开发了将零件信息、材料信息与套料板信息集成化管理的精益造船辅助系统。%This paper summarized the lean manufacturing and agile manufacturing’s development and applies. Through survey and research particular in this enterprise, combined management and production factors, author set up two ideas:ifrstly, integrated management in parts data, materials information and nesting information. Taking nesting work as core, complete all nesting work in this system, and it could search and statistically analyze nesting data.

  6. 燃气热水器辅助太阳能热水系统的应用%The application of gas water heater auxiliary solar water heating system

    Institute of Scientific and Technical Information of China (English)

    桑松表

    2015-01-01

    This paper introduced the component of solar hot water system,made comparison and selection to boiler heating,electric heating,gas water heater heating three traditional auxiliary heat sources,pointed out that the gas water heater auxiliary heat source had the advantages of sav-ing the space,short system restart time,convenient to intermittent.%介绍了太阳能热水系统的组成要素,对锅炉加热、电加热、燃气热水器加热三种传统的辅助热源进行了比选,指出选用燃气热水器辅助热源具有节省空间,重启时间短,便于间断使用等优点。

  7. An integral effect test on the feedwater line break of APR1400 with the ATLAS facility

    International Nuclear Information System (INIS)

    An integral effect test on the feedwater line break (FLB) was performed with the ATLAS facility for an APR1400 as a typical secondary system transient. The objectives of the present FLB tests are to understand the accident progression of the FLB scenario based on the APR1400 preliminary safety analysis report (PSAR) and to assess the prediction capability of system analysis codes such as the MARS, RELAP5, TRACE and SPACE. The main concern of the present FLB test is the peak RCS pressure and the major parameters affecting the peak RCS pressure are the break size, the break location, potential for reverse flow, initial pressurizer level and the initial SG level. The present test is performed for a break on the pipe connected to the economizer with a typical break size. The initial steady-state conditions and the sequence of event of FLB scenario for the APR1400 were successfully simulated with the ATLAS facility. In the present paper, major thermal-hydraulic phenomena such as the system pressures, the collapsed water levels, and the break flow rate are presented and discussed. It could be concluded that the APR1400 has the capability of coping with the hypothetical FLB scenario with an adequate set of controlling devices and proper setpoints. This integral effect test data could also be used to evaluate the prediction capability of existing safety analysis codes of MARS, RELAP5 and SPACE and to identify any code deficiency for an FLB simulation. (author)

  8. 新时期辅警制度的现实困局与探索路径%Dilemma and Exploration of the Auxiliary Police System in the New Era

    Institute of Scientific and Technical Information of China (English)

    刘显峰

    2015-01-01

    As a useful complement to the regular police force, the Auxiliary Police has played an important role in maintaining security and stability and become an indispensable auxiliary security force. However, in the process of system construction and actual operation of auxiliary police system, there appeared many problems, such as the diversity of auxiliary police titles, lack of security, awkwardness of identity positioning, etc. How to further strengthen the management and construction of the auxiliary police force and actively promote its sustainable and healthy development is the issue which public security organs cannot be avoided. It is believed that in order to vigorously promote the normalization and institutionalization of the auxiliary police, the management and construction should be standardized, the assessment should be lfexible, the skills should be specialized and the work should be transparent.%作为正规警力的有益补充,辅警在协助警察维护社会治安等方面发挥了重要作用,成为维护安全稳定不可或缺的治安辅助力量。不过,辅警体系的制度构建和现实运作也出现了辅警称谓多样化、成员复杂、缺乏保障、身份定位尴尬等一系列问题。加强辅警队伍的管理和建设,积极推动辅警队伍持续健康发展,是公安机关不容回避的现实问题。对于辅警队伍的管理与建设应从管理规范化、考核灵活化、技能专业化、工作透明化四个方面入手,大力推进辅警队伍的正规化、制度化建设。

  9. Auxiliary nRules of Quantum Mechanics

    CERN Document Server

    Mould, R A

    2005-01-01

    Standard quantum mechanics makes use of four auxiliary rules that allow the Schrodinger solutions to be related to laboratory experience, such as the Born rule that connects square modulus to probability. These rules (here called the sRules) lead to some unacceptable results. They do not allow the primary observer to be part of the system. They do not allow individual observations (as opposed to ensembles) to be part of the system. They make a fundamental distinction between microscopic and macroscopic things, and they are ambiguous in their description of secondary observers such as Schrodingers cat. The nRules are an alternative set of auxiliary rules that avoid the above difficulties. In this paper we look at a wide range of representative experiments showing that the nRules adequately relate the Schrodinger solutions to empirical experience. This suggests that the sRules should be abandoned in favor of the more satisfactory nRules, or a third auxiliary rule-set called the oRules. Keywords: brain states, c...

  10. Analysis of a loss of feedwater transient with safety/relief valve stuck open in Chin Shan Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    Liao, L.Y.; Guey, C.N.; Chen, Y.B.; Lee, C.H.

    1980-06-01

    An analysis has been made with RELAP 4/MOD5 to simulate the system behavior of loss of feedwater transient with safety/relief valve stuck open in Chin Shan BWR. The initial conditions have been established with 105% rated power and 105% flow rate. System variables such as normalized power, steam dome pressure, core inlet flow rate, fuel cladding temperatures, separator mixture level, downcomer mixture level, and core inlet enthalpy have been calculated. A comparison has also been made between the results obtained and those documented in FSAR. It is observed that the general trends of system parameters in both cases are similar, differing slightly only in the timing of the sequence of events postulated to occur. The possibility of idling of ECCS as a result of pool swelling is ruled out. Core uncovery is not observed. In conclusion, the accident analyzed can be accommodated by the design incorporated in the Chin Shan Plant.

  11. Global stratification effects in feedwater line to steam generator in PWR power plant

    International Nuclear Information System (INIS)

    Recent measurements recorded at Beaver Valley Power Station-Unit 1, a PWR plant, demonstrate the presence of significant global thermal stratification within horizontal sections of the feedwater line. Global thermal stratification has not been documented nor its effects quantified on pressurized water reactor feedwater piping. An investigation of the feedwater line at BV-1 was performed to determine the effects of global stratification. Plant specific operating data were gathered for a recent plant restart using temporary instrumentation installed to measure piping temperatures and displacements. Data reduction identified significant global thermal stratification and significant pipe movement during several operating modes. Steps were taken to incorporate its effects into the design calculations when the global thermal stratification was determined to be an unanalyzed condition which was not enveloped by the existing design basis calculations

  12. Modeling and simulation on feed-water heater of nuclear power plant

    International Nuclear Information System (INIS)

    The feed-water heater is one of the major equipment in the secondary loop of nuclear power plant (NPP), and its behavior has an important influence on the safe and economical operation of NPP. The research on the behavior of feed-water heater by means of modeling and simulation can provide important theoretical basis for its design and operation. In this paper, the distributed parameter dynamic models of NPP feed water heater were established, in which the nearly separated model was used to deal with two-phase flow. By simulating the behavior of actual NPP feed-water heaters under various operating conditions and comparing the differences between the simulation values and the actual values, the accuracy of the simulation models was proven to be higher than that of existing models. (authors)

  13. Feedwater transient and small break loss of coolant accident analyses for the Bellefonte Nuclear Plant

    International Nuclear Information System (INIS)

    Specific sequences that may lead to core damage were analyzed for the Bellefonte nuclear plant as part of the US Nuclear Regulatory Commission's Severe Accident Sequence Analysis Program. The RELAP5, SCDAP, and SCDAP/RELAP5 computer codes were used in the analyses. The two main initiating events investigated were a loss of all feedwater to the steam generators and a small cold leg break loss of coolant accident. The transients of primary interest within these categories were the TMLB' and S2D sequences. Variations on systems availability were also investigated. Possible operator actions that could prevent or delay core damage were identified, and two were investigated for a small break transient. All of the transients were analyzed until either core damage began or long-term decay heat removal was established. The analyses showed that for the sequences considered the injection flow from one high-pressure injection pump was necessary and sufficient to prevent core damage in the absence of operator actions. Operator actions were able to prevent core damage in the S2D sequence; no operator actions were available to prevent core damage in the TMLB' sequence

  14. Novel Chiral Auxiliaries of BIAZOLs

    Institute of Scientific and Technical Information of China (English)

    CHEN; Arh-Hwang

    2001-01-01

    Asymmetric catalysis is one of the most challenging and formidable endeavor in organic synthesis. The development of chiral auxiliaries is a key in the asymmetric catalysis. Azulenoids, a parent structure of bicyclo[5.3.0]decapentaene with 10 πelectrons, are useful as dye materials, medical treatment of inflammation and hypertension, and the development of liquid crystals. In continuing to investigate synthetic application of azulenoids, we have studied to develop novel chiral auxiliaries of BIAZOLs. The BIAZOLs were synthesized from dicyclopentadiene and characterized using spectroscopies.  ……

  15. Novel Chiral Auxiliaries of BIAZOLs

    Institute of Scientific and Technical Information of China (English)

    CHEN Arh-Hwang; YUAN Shou-Bin; CHIU Shu-Ching

    2001-01-01

    @@ Asymmetric catalysis is one of the most challenging and formidable endeavor in organic synthesis. The development of chiral auxiliaries is a key in the asymmetric catalysis. Azulenoids, a parent structure of bicyclo[5.3.0]decapentaene with 10 πelectrons, are useful as dye materials, medical treatment of inflammation and hypertension, and the development of liquid crystals. In continuing to investigate synthetic application of azulenoids, we have studied to develop novel chiral auxiliaries of BIAZOLs. The BIAZOLs were synthesized from dicyclopentadiene and characterized using spectroscopies.

  16. Thermal-hydraulics of PGV-4 water volume during damage of the feedwater collector nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Logvinov, S.A.; Titov, V.F. [OKB Gidropress (Russian Federation); Notaros, U.; Lenkei, I. [NPP Paks (Hungary)

    1995-12-31

    A number of VVER-440 plants has experienced the distributing nozzles of feedwater collector being damaged due to corrosion-erosion wearing. Such phenomenon could result in feedwater redistribution within the SG inventory with undesirable consequences. The collector with damaged nozzles has to be replaced but a certain time is needed for the preparatory works. The main objective of the investigation conducted is to assess if the safe operation of SG is possible before collector replacement. It was shown that the nozzle damage as observed did not result in the dangerous disturbances of thermobydraulics as compared with the conditions existing at the initial period of operation. (orig.).

  17. Loss-of-feedwater, steam generator tube rupture, and steam line break experiments: Steam generator transient response test program: Interim report

    International Nuclear Information System (INIS)

    The Westinghouse Model Boiler No. 2 (MB-2) steam generator test model at the Engineering Test Facility in Tampa, Florida, was reinstrumented and modified for performing a series of tests simulating steam generator accident transients. The transients simulated were: loss of feed flow, steam generator tube rupture, and steam line break events. This document presents a description of (1) the model boiler and the associated test facility, (2) the tests performed, and (3) the analyses of the test results. Two LOF tests were analyzed in detail. Both tests were initiated from 100% power condition by shutting off the main feedwater flow. In LOF Test No. 1, the remaining boundary conditions were kept constant while in LOF Test No. 2, the power was rapidly reduced to 3%. The results show that the primary to secondary heat transfer becomes degraded when the collapsed water liquid level in the bundle region falls below approximately 50 inches. The SGTR test analyzed in detail - SGTR Test No. 2 - simulated the post-reactor-trip portion of the SGTR transient (T/sub prim/ = 5600F). The transient was initiated by starting the SGTR flow injection and simultaneously shutting off the auxiliary feedwater. The water level rose and flooded the dryer to its mid-elevation by the end of the test. The primary carry-over was shown to be less than 0.4% of the tracer mass injected into the secondary side by the SGTR flow. SGTR Test No. 3 investigated the response of the intact steam generator. Reverse heat transfer and low heat flow conditions were simulated. The results have demonstrated the occurrence of temperature stratification in the secondary water which lasted for about 800 seconds

  18. 1000 MW超超临界机组给水全程控制的设计和应用%Design and Application of Global Feedwater Control in 1 000 MW Ultra Supercritical Units

    Institute of Scientific and Technical Information of China (English)

    张利勇; 刘潇

    2013-01-01

    超超临界机组的给水控制既承担过热汽温控制又与负荷控制密不可分,在机组启停阶段还承担防止蒸发器超温和水动力稳定的重要任务,是超超临界机组控制系统的核心和难点,而其全程控制的实现也是机组级顺控(APS)能否实现的重要一环。详细介绍给水全程控制3种模式(停炉、湿态和干态)的控制原理及其切换过程、干态模式下的煤水比控制和焓值控制原理,给出了给水全程控制中特殊工况的处理原则和方案。%Feedwater control in ultra supercritical units is responsible for temperature control of superheated steam and closely related to unit load control. During unit startup and shutdown, feedwater control takes the important task to prevent the evaporator overtemperature and stabilize the hydrodynamic. It is the core and difficulty of control system of ultra supercritical units, and the realization of the global feedwater control is one of the important links of the implementation of automatic plant startup and shutdown control system (APS). Closed-loop of feed water entire-process control is described by taking a real case. The control theory and switching process of the three modes (furnace shutdown, wet and dry) of global feedwater control, coal-water ratio control and enthalpy control principle in dry mode are expounded. The paper presents principle of management and scheme for special operating condition in global feedwater control.

  19. Diagnosis of Feedwater Heater Performance Degradation using Fuzzy Approach

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyeonmin; Kang, Yeon Kwan; Heo, Gyunyoung [Kyung Hee Univ., Yongin (Korea, Republic of); Song, Seok Yoon [Korea Hydro and Nuclear Power, Daejeon (Korea, Republic of)

    2014-05-15

    It is inevitable to avoid degradation of component, which operates continuously for long time in harsh environment. Since this degradation causes economical loss and human loss, it is important to monitor and diagnose the degradation of component. The diagnosis requires a well-systematic method for timely decision. Before this article, the methods using regression model and diagnosis table have been proposed to perform the diagnosis study for thermal efficiency in Nuclear Power Plants (NPPs). Since the regression model was numerically less-stable under changes of operating variables, it was difficult to provide good results in operating plants. Contrary to this, the diagnosis table was hard to use due to ambiguous points and to detect how it affects degradation. In order to cover the issues of previous researches, we proposed fuzzy approaches and applied it to diagnose Feedwater Heater (FWH) degradation to check the feasibility. The degradation of FWHs is not easy to be observed, while trouble such as tube leakage may bring simultaneous damage to the tube bundle. This study explains the steps of diagnosing typical failure modes of FWHs. In order to cover the technical issues of previous researches, we adopted fuzzy logic to suggest a diagnosis algorithm for the degradation of FHWs and performed feasibility study. In this paper, total 7 modes of FWH degradation modes are considered, which are High Drain Level, Low Shell Pressure, Tube Pressure Increase, Tube Fouling, Pass Partition Plate Leakage, Tube Leakage, Abnormal venting. From the literature survey and simulation, diagnosis table for FWH is made. We apply fuzzy logic based on diagnosis table. Authors verify fuzzy diagnosis for FWH degradation synthesized the random input sets from made diagnosis table. Comparing previous researches, suggested method more-stable under changes of operating variables, than regression model. On the contrary, the problem which ambiguous points and detect how it affects degradation

  20. Hydraulic turbines and auxiliary equipment

    Energy Technology Data Exchange (ETDEWEB)

    Luo Gaorong [Organization of the United Nations, Beijing (China). International Centre of Small Hydroelectric Power Plants

    1995-07-01

    This document presents a general overview on hydraulic turbines and auxiliary equipment, emphasizing the turbine classification, in accordance with the different types of turbines, standard turbine series in China, turbine selection based on the basic data required for the preliminary design, general hill model curves, chart of turbine series and the arrangement of application for hydraulic turbines, hydraulic turbine testing, and speed regulating device.

  1. Decontamination of the reactor pressure vessel and further internals and auxiliary systems in the German boiling water reactor Isar-1; Dekontamination des RDB inkl. der Einbauten wie Dampftrockner und Wasserabscheider sowie der angeschlossenen Hilfssysteme im deutschen Siedewasserreaktor ISAR 1

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Michael; Sempere Belda, Luis; Basu, Ashim; Topf, Christian [AREVA GmbH, Erlangen (Germany). Abt. Chemistry Services; Erbacher, Thomas; Hiermer, Thomas; Schnurr, Bernhard; Appeldorn, Thomas van [E.ON Kernkraft GmbH, Kernkraftwerk ISAR, Essenbach (Germany). Abt. Maschinentechnik; Volkmann, Christian [ESG Engineering Services GmbH, Greifswald (Germany)

    2015-12-15

    The German nuclear power plant ISAR 1 (KKI 1), a 878 MWe boiling water reactor of KWU design, was shut down on March 17{sup th}, 2011. With the objective to minimize the plants activity inventory accompanied by the reduction of contact dose rates of systems and components the project 'decontamination of the RPV incl. steam dryer and water separator and the connected auxiliary systems' was implemented in the first quarter of 2015. One major focus within the project was the specific in-situ decontamination of the steam dryer.

  2. 45 CFR 707.10 - Auxiliary aids.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Auxiliary aids. 707.10 Section 707.10 Public Welfare Regulations Relating to Public Welfare (Continued) COMMISSION ON CIVIL RIGHTS ENFORCEMENT OF... § 707.10 Auxiliary aids. (a) The Agency shall furnish appropriate auxiliary aids where necessary...

  3. 7 CFR 15b.37 - Auxiliary aids.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Auxiliary aids. 15b.37 Section 15b.37 Agriculture... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.37 Auxiliary aids... appropriate auxiliary aids to persons with impaired sensory, manual, or speaking skills, where necessary...

  4. Ligand-Enabled β-C–H Arylation of Alpha-Amino Acids Using a Simple and Practical Auxiliary

    OpenAIRE

    Chen, Gang; Shigenari, Toshihiko; Jain, Pankaj; Zhang, Zhipeng; Jin, Zhong; He, Jian; Li, Suhua; Mapelli, Claudio; Miller, Michael M.; Poss, Michael A.; Scola, Paul M.; Yeung, Kap-Sun; Yu, Jin-Quan

    2015-01-01

    Pd-catalyzed β-C–H functionalizations of carboxylic acid derivatives using an auxiliary as a directing group have been extensively explored in the past decade. In comparison to the most widely used auxiliaries in asymmetric synthesis, the simplicity and practicality of the auxiliaries developed for C–H activation remains to be improved. We previously developed a simple N-methoxyamide auxiliary to direct β-C–H activation, albeit this system was not compatible with carboxylic acids containing α...

  5. Pilot RCM application to the Diablo Canyon main stream system

    International Nuclear Information System (INIS)

    In 1986 Pacific Gas ampersand Electric Company (PG ampersand E) became extremely interested in reliability-centered maintenance (RCM) after the initial review of two successful Electric Power Research Institute sponsored projects. RCM was visualized as a methodology to common sensitize the burgeoning preventive maintenance (PM) program at the Diablo Canyon plant. RCM could further the uses of predictive and condition-monitoring techniques, as well as eliminate maintenance on components whose failures were noncritical. An extensive review of maintenance and operation experience data, in conjunction with plant staff recommendations and a prioritization according to maintenance expenditures and operational/safety significance, produced the selected system: the turbine main steam supply system (main steam). The pilot project segmented the main steam system into eight subsystems to aid in analysis: (a) main steam isolation valves, (b) auxiliary feedwater pump turbine, (c) overpressure protection (steam dump), (d) main feedwater pump turbines, (e) main steam, (f) main turbine, (g) steam blowdown, and (h) moisture separator reheaters. System analysis activities, including the preparation of functional failure analyses, failure modes and effects analyses, and logic model analyses, were conducted in parallel with corrective and preventive maintenance data-gathering activities to maximize project team personnel participation during the project. Results and lessons learned are summarized

  6. Data report of ROSA/LSTF experiment TR-LF-07; Loss-of-feedwater transient with primary feed-and-bleed operation

    OpenAIRE

    竹田 武司

    2016-01-01

    The TR-LF-07 test simulated a loss-of-feedwater transient in a PWR. A SI signal was generated when steam generator (SG) secondary-side collapsed liquid level decreased to 3 m. Primary depressurization was initiated by fully opening a power-operated relief valve (PORV) of pressurizer (PZR) 30 min after the SI signal. High pressure injection (HPI) system was started in loop with PZR 12 s after the SI signal, while it was initiated in loop without PZR when the primary pressure decreased to 10.7 ...

  7. 太阳能-蒸汽源与锅炉辅助供暖系统节能效益分析%Analysis on Energy Efficiency of Solar-Steam Sourceand Boiler Auxiliary Heating System

    Institute of Scientific and Technical Information of China (English)

    高越; 高丽娜; 孙清

    2015-01-01

    针对呼伦贝尔地区某工业区民用建筑热水供暖、电热水器为洗浴供热工程存在的缺点,提出太阳能-蒸汽源与锅炉辅助供暖系统,对改造后的工程进行实际测试,用DeST模拟探讨室内热环境和节能效益。结果表明,使用太阳能-蒸汽源与锅炉辅助供暖系统的室内环境得到明显改善,节能率可达到66.46%。%Aiming at the disadvantages existing in the project of civil construction hot water heating and bath heating by electric hotwater heater in a certain industrial area in Hulunbeir, it raised solar-steam source and boiler auxiliary heating system, and did practicaltest for the project after improving, used DeST to simulate to discuss indoor thermal environment and energy efficiency. The result showsthat the indoor environment is obviously improved after using solar-steam source and boiler auxiliary heating system, the energy savingrate can achieve 66.46%.

  8. 汽车辅助制动系统及试验方法研究%Study on Automotive Auxiliary Braking System and Test Method

    Institute of Scientific and Technical Information of China (English)

    王勇; 张雄; 刘翰东

    2013-01-01

    The authors introduce the type and principles of the auxiliary braking types, and describe the require-ments and test methods of typeⅡand typeⅡA tests. Through simulating the ramp test, they verify the meeting of the exhaust braking and the retarder braking to the standard, and put forward the relative recommendations.%介绍辅助制动装置的类型及原理,并对Ⅱ型和ⅡA型试验的要求和试验方法进行阐述。通过模拟坡道试验,验证排气制动和缓速器对标准的满足性,并给出相应建议。

  9. Research on aviation guaranteeing equipment auxiliary analysis decision system based on RCM%航空保障装备RCM辅助分析决策系统研究

    Institute of Scientific and Technical Information of China (English)

    朱日春; 谢立军; 周伟

    2013-01-01

    通过研究以可靠性为中心的维修理论,明确了航空保障装备系统和设备的RCM分析程序,结合计算机开发软件Visual C++、SQL Server 2000和Matlab,设计航空保障装备RCM辅助分析决策系统框架和功能模块,研发了航空保障装备RCM辅助分析决策系统.%Through the research of reliability centered mainHniRpe theory,this paper clears the aviation "Utipprt equipment systems and equipment RCM analysis program. Combining with computer system software of Visual C ++ , SQL Server 2000 and Matlab, it develops the aviation support equipment RCM auxiliary analysis decision system by designing its system framework and functional module.

  10. Hovercraft auxiliary power units (APUs)

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.J.

    1983-08-01

    Auxiliary power units (APU) manufactured by British firms for use in hovercraft are characterized. Both diesel and gas-turbine APUs are found to be well suited to the demands of this application. The design features, dimensions, performance data, and installation requirements are discussed for the SS 90, SS 923, DA-1, BA-1, HM 5, and Gevaudan 9 APUs, as well as the TRS 18 gas-turbine smoke generator. The progress made in improving the fuel efficiency of gas turbines and reducing the weight of diesel engines is considered significant.

  11. Power-feedwater temperature operating domain for Sbwr applying Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar M, L. A.; Quezada G, S.; Espinosa M, E. G.; Vazquez R, A.; Varela H, J. R.; Cazares R, R. I.; Espinosa P, G., E-mail: sequega@gmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)

    2014-10-15

    In this work the analyses of the feedwater temperature effects on reactor power in a simplified boiling water reactor (Sbwr) applying a methodology based on Monte Carlo simulation is presented. The Monte Carlo methodology was applied systematically to establish operating domain, due that the Sbwr are not yet in operation, the analysis of the nuclear and thermal-hydraulic processes must rely on numerical modeling, with the purpose of developing or confirming the design basis and qualifying the existing or new computer codes to enable reliable analyses. The results show that the reactor power is inversely proportional to the temperature of the feedwater, reactor power changes at 8% when the feed water temperature changes in 8%. (Author)

  12. Actual flow calibration of a feedwater flowmeter using a high Reynolds number facility at NMIJ

    Energy Technology Data Exchange (ETDEWEB)

    Furuichi, Noriyuki [Fluid Flow Division, National Metrology Institute of Japan, AIST, Tsukuba Central 3, 1-1-1 Umezono, Tsukuba, 305-8563 (Japan)], E-mail: furuichi.noriyuki@aist.go.jp; Terao, Yoshiya [Fluid Flow Division, National Metrology Institute of Japan, AIST, Tsukuba Central 3, 1-1-1 Umezono, Tsukuba, 305-8563 (Japan)], E-mail: yterao@ni.aist.go.jp; Takamoto, Masaki [Fluid Flow Division, National Metrology Institute of Japan, AIST, Tsukuba Central 3, 1-1-1 Umezono, Tsukuba, 305-8563 (Japan)], E-mail: m.takamoto@nifty.ne.jp

    2009-07-15

    The results of calibration tests of the feedwater flowrate of ultrasonic flowmeters used in a nuclear power plant for variety of upstream conditions obtained using the new high Reynolds number calibration facility at NMIJ are described. In this examination, the measurements are performed for five pattern pipe layouts with one or two elbows. The flow conditioners installed upstream of the flowmeter are the tube bundle type and the Mitsubishi, which are normally used in nuclear power plants. The calibration result for each flowmeter are largely different for each flow conditioner and each upstream pipe layout, except in some special cases. Moreover, the trend of the correction factor with Reynolds number is not uniform for each case. Furthermore, some differences were observed for individual flowmeters. It is recommended that the feedwater flowmeter, especially when used to perform measurement uncertainty recapture, is calibrated based on the actual pipe layout and the Reynolds number corresponding to the actual nuclear power plant conditions.

  13. The solar energy hot water system paired with auxiliary heat system of air source heat pump%以空气源热泵辅助加热的太阳能热水系统

    Institute of Scientific and Technical Information of China (English)

    施龙; 刘刚; 杨丰畅

    2013-01-01

    介绍了太阳能热泵热水系统的运行原理及控制方式,分析了太阳能热泵热水系统在上海某高校 学生宿舍的应用情况.以每吨热水的加热成本为指标,对几种热源热水系统的经济性进行了比较,分析了太阳能热泵热水系统的节能效果.%An operating principles and control strategies of solar energy hot water system with air source heat pump for auxiliary heating were introduced. Then an application in the students' dormitories of one university in Shanghai was analyzed. Basing on an index which was the cost of heating 1 ton water, the economic efficiency of several heat sources was compared, and higher energy-saving effect of current system was concluded.

  14. Developing the optimum boiler water and feedwater treatment for fossil plants

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, B. [Electric Power Research Inst., Palo Alto, California (United States)

    1996-12-01

    Over the last two years a new set of cycle chemistry guidelines has been developed for each of the treatments used in fossil plants. These revisions have been based on research conducted over the last ten years, much at the international collaborative level. By careful selection and optimization of the boiler water and feedwater treatments, it will be possible to accrue large financial, maintenance, availability and performance improvements. (au) 14 refs.

  15. Assessment of the code RELAP5/MOD2 against loss of feedwater without scram

    International Nuclear Information System (INIS)

    The integral effect test L9-3 (loss of feedwater without reactor trip) performed at the LOFT facility was analyzed as part of an assessment of the RELAP5/MOD2 code with the aim of qualifying this simulation tool for analysis of pressurization transients in pressurized water reactors. The code proved suitable for analysis of this kind of transients. Some conclusions of relevance to simulation of anticipated transients without scram scenarios with forced circulation could be drawn. (orig.)

  16. Assessment of the code RELAP5/MOD2 against loss of feedwater without scram

    Energy Technology Data Exchange (ETDEWEB)

    Rebollo, L. (Union Fenosa, Madrid (Spain))

    1993-02-01

    The integral effect test L9-3 (loss of feedwater without reactor trip) performed at the LOFT facility was analyzed as part of an assessment of the RELAP5/MOD2 code with the aim of qualifying this simulation tool for analysis of pressurization transients in pressurized water reactors. The code proved suitable for analysis of this kind of transients. Some conclusions of relevance to simulation of anticipated transients without scram scenarios with forced circulation could be drawn. (orig.).

  17. Bispinor Auxiliary Fields in Duality-Invariant Electrodynamics Revisited

    OpenAIRE

    Ivanov, E. A.; Zupnik, B. M.

    2012-01-01

    Motivated by a recent progress in studying the duality-symmetric models of nonlinear electrodynamics, we revert to the auxiliary tensorial (bispinor) field formulation of the O(2) duality proposed by us in arXiv:hep-th/0110074, arXiv:hep-th/0303192. In this approach, the entire information about the given duality-symmetric system is encoded in the O(2) invariant interaction Lagrangian which is a function of the auxiliary fields V_{\\alpha\\beta}, \\bar V_{\\dot \\alpha\\dot \\beta}. We extend this s...

  18. Perfects, resultatives and auxiliaries in early English

    OpenAIRE

    McFadden, Thomas; Alexiadou, Artemis

    2008-01-01

    In this paper, we will argue for a novel analysis of the auxiliary alternation in Early English, its development and subsequent loss which has broader consequences for the way that auxiliary selection is looked at cross-linguistically. We will present evidence that the choice of auxiliaries accompanying past participles in Early English differed in several significant respects from that in the familiar modern European languages. Specifically, while the construction with have became a full-fle...

  19. 燃料电池汽车空辅系统噪声有源控制技术%Active Noise Control Technology of Air Auxiliary System in Fuel Cell Vehicles

    Institute of Scientific and Technical Information of China (English)

    胡佳杰; 左曙光; 何吕昌; 张孟浩

    2013-01-01

      燃料电池汽车(FCV)的动力系统及噪声特性与传统汽车相比有着很大差异,其中空气辅助系统已成为主要的噪声源。虽然有源噪声控制(ANC)是近年来的研究热点;但是,由于噪声源与环境的时变性,对空辅系统的中低频段噪声更有效的对策是使用自适应有源噪声控制技术(AANC)。在归纳总结有源噪声控制技术的发展进程及基本原理的基础上,阐述近年来有源噪声控制的研究现状,并重点分析关注自适应算法的研究进展;由此对自适应有源噪声控制在燃料电池汽车空辅系统减振降噪方面的应用前景进行预测和展望。%The power system and its noise characteristic of Fuel Cell Vehicle (FCV) are quite different from those of traditional cars. In FCV, the air auxiliary system becomes one of the main noise sources. In recent years, active noise control (ANC) has become a research focus. It has advantages for the traditional passive noise control in middle-and low-frequency range. However, because of the time-variation property of noise sources and environments, it is necessary to use adaptive active noise control (AANC) in middle-and low-frequency noise control of the air auxiliary system in FCV. In this paper, the development progress of ANC technology was summarized, and the research of ANC in recent years was expatiated. Analysis was focused on the research progress of adaptive algorithm. Finally, the prospect of the ANNC application in the field of vibration and noise reduction of the air auxiliary system in FCV was forecasted.

  20. Analysis of ultrasound propagation in high-temperature nuclear reactor feedwater to investigate a clamp-on ultrasonic pulse doppler flowmeter

    International Nuclear Information System (INIS)

    The flow rate of nuclear reactor feedwater is an important factor in the operation of a nuclear power reactor. Venturi nozzles are widely used to measure the flow rate. Other types of flowmeters have been proposed to improve measurement accuracy and permit the flow rate and reactor power to be increased. The ultrasonic pulse Doppler system is expected to be a candidate method because it can measure the flow profile across the pipe cross section, which changes with time. For accurate estimation of the flow velocity, the incidence angle of ultrasound entering the fluid should be estimated using Snell's law. However, evaluation of the ultrasound propagation is not straightforward, especially for a high-temperature pipe with a clamp-on ultrasonic Doppler flowmeter. The ultrasound beam path may differ from what is expected from Snell's law due to the temperature gradient in the wedge and variation in the acoustic impedance between interfaces. Recently, simulation code for ultrasound propagation has come into use in the nuclear field for nondestructive testing. This article analyzes and discusses ultrasound propagation, using 3D-FEM simulation code plus the Kirchhoff method, as it relates to flow profile measurement in nuclear reactor feedwater with the ultrasonic pulse Doppler system. (author)

  1. Effects of auxiliary heat sources on energy efficiency of active solar heating systems%辅助热源对主动式太阳能供暖系统节能性的影响

    Institute of Scientific and Technical Information of China (English)

    于国清; 周继瑞

    2015-01-01

    根据太阳能贡献率和辅助加热设备的能源效率,将系统的能耗折算成一次能源,分析不同辅助热源对太阳能供暖系统节能性的影响,认为主动式太阳能供暖系统要达到节能效果必须满足一定的前提条件。研究结果表明:辅助热源方式和太阳能贡献率对系统的节能性影响很大;相对于燃气锅炉单独供暖,电加热辅助太阳能供暖系统只有在太阳能贡献率高于65.4%时才节能,而大多数系统的太阳能贡献率很难达到这么高,因此要尽量避免使用;热泵辅助太阳能供暖系统在大多数情况下都是节能的(热泵的平均 COP =2.5时,太阳能贡献率需高于7%);采用平均COP 高于3.0的热泵或采用燃气锅炉作为辅助热源时,系统都是节能的,太阳能贡献率越高,节能效果越明显。%According to the solar fraction and the energy efficiency of auxiliary heating equipments, analyses the effects of different auxiliary heat sources on the energy efficiency of active solar heating systems by converting energy consumption to primary energy,and believes that the active solar heating system must satisfy certain conditions for achieving energy saving effect.The results indicate that the auxiliary heat source and the solar fraction have a great impact on the energy efficiency of solar heating systems.Compared to the gas-fired boiler heating alone,the solar heating system assisted by electric heating is energy efficient only when the solar fraction is greater than 65.4%,which is very difficult to achieve for many real systems.The primary energy consumption of the solar heating system assisted by heat pump is lower in general instances (when the average COP of heat pump is 2.5,the solar fraction should be greater than 7%).When heat pumps with average COP above 3.0 or gas-fired boilers are used as auxiliary heat sources,the solar heating system is energy efficient,and the higher the solar

  2. Auxiliary bearing design and rotor dynamics analysis of blower fan for HTR-10

    International Nuclear Information System (INIS)

    The electromagnetic bearing instead of ordinary mechanical bearing was chosen to support the rotor in the blower fan system with helium of 10 MW high temperature gas-cooled test reactor (HTR-10), and the auxiliary bearing was applied in the HTR-10 as the backup protector. When the electromagnetic bearing doesn't work suddenly for the power broken, the auxiliary bearing is used to support the falling rotor with high rotating speed. The rotor system will be protected by the auxiliary bearing. The design of auxiliary bearing is the ultimate safeguard for the system. This rotor is vertically mounted to hold the blower fan. The rotor's length is about 1.5 m, its weight is about 240 kg and the rotating speed is about 5400 r/min. Auxiliary bearing design and rotor dynamics analysis are very important for the design of blower fan to make success. The research status of the auxiliary bearing was summarized in the paper. A sort of auxiliary bearing scheme was proposed. MSC.Marc was selected to analyze the vibration mode and the natural frequency of the rotor. The scheme design of auxiliary bearing and analysis result of rotor dynamics offer the important theoretical base for the protector design and control system of electromagnetic bearing of the blower fan. (authors)

  3. Development of an auxiliary system for the execution of vascular catheter interventions with a reduced radiological risk; system description and first experimental results.

    Science.gov (United States)

    Placidi, Giuseppe; Franchi, Danilo; Marsili, Luca; Gallo, Pasquale

    2007-11-01

    Vascular catheterization is a common procedure in clinical medicine. It is normally performed by a specialist using an X-ray fluoroscopic guide and contrast-media. In the present paper, an image-guided navigation system which indicates a path providing guidance to the desired target inside the vascular tree is described with the aim of reducing the exposure of personnel and patients to X-rays during the catheterization procedure. A 3D model of the patient vascular tree, reconstructed with data collected by an angiography before starting the intervention, is used as a guide map instead of fluoroscopic scans. An accurate spatial correspondence between the body of the patient and the 3D reconstructed vascular model is established and, by means of a position indicator installed over the catheter tip, the real-time position/orientation of the tip is indicated correctly. This paper describes the system and the operational procedures necessary to use the proposed method efficiently during a catheter intervention. Preliminary experimental results on a phantom are also reported.

  4. Auxiliary-field quantum Monte Carlo methods in nuclei

    CERN Document Server

    Alhassid, Y

    2016-01-01

    Auxiliary-field quantum Monte Carlo methods enable the calculation of thermal and ground state properties of correlated quantum many-body systems in model spaces that are many orders of magnitude larger than those that can be treated by conventional diagonalization methods. We review recent developments and applications of these methods in nuclei using the framework of the configuration-interaction shell model.

  5. An Improved Auxiliary Particle Filter Algorithm for Information Fusion in Multi-Agent System%改进的辅助粒子多Agent系统信息融合滤波算法

    Institute of Scientific and Technical Information of China (English)

    朱波; 陈贞翔

    2012-01-01

    In order to overcome the nonlinear problem and improve the collaborative capabilities in the multi-agent system, this paper proposes an improved auxiliary particle information fusion filter algorithm. The architecture of multi-agent system is analyzed, then the signal of agent is decomposed and reconstructed based on orthogonal wavelet multi-scale analysis theory, so the improved auxiliary particle information fusion filter algorithm is proposed based on the signal of agent, which can be taken as the important sampling density function,after that,the features are integrated into multi-agent system's features. Finally,this algorithm is applied to the maneuvering target tracking through computer simulation and compared with conventional algorithms,and simulation results verify its effectiveness.%为克服多Agent系统的非线性问题,提高多Agent系统对信息的协同合作能力,提出一种改进的辅助粒子信息融合滤波算法.该算法通过分析多Agent系统的结构,根据正交小波多尺度分析理论对系统内Agent的信息进行分解、重构,给出以Agent信息为重要采样密度函数的辅助粒子滤波算法,并对滤波结果进行特征融合,得到多Agent系统融合特征.将此算法应用到机动目标跟踪领域,并与传统的滤波算法进行对比,仿真结果验证了该算法的有效性.

  6. Design of a Wide-input Auxiliary Power Supply in the PV Inverter System%一种光伏并网系统用的宽输入辅助电源设计

    Institute of Scientific and Technical Information of China (English)

    胡天友; 张晓博; 王海; 刘洋

    2012-01-01

    根据光伏并网逆变系统的供电需求,设计了一种120 ~ 850 V宽输入的辅助电源.为防止在输入电压过高时丢失开通脉冲,在传统的单端反激式拓扑电路的基础上加入了变频电路.输入电压升高时,降低开关频率,保证导通时间大于开关管的最小导通时间,实现了宽输入范围电压的要求.采用DCM工作模式,峰值电流控制,在反馈电路中加入了2型补偿网络,保证了输出电压快速调节性和稳定性.样机实验结果表明,该电源能够适应输入电压在大范围波动,可靠地为光伏并网实验系统供电.%According to the requirement of the PV grid-connected inverter system, an auxiliary power supply with an input voltage of 120 -850 V is designed. To avoid losing the opening pulse at a high input voltage, a circuit that can change switching frequency based on the input voltage is introduced. The peak current control and DCM work mode is used, and the type-2 compensation circuit in the feedback loop guarantees the rapid adjustment of output voltage and stability of the system. Experimental results show that this auxiliary power supply can adapt to a wide fluctuation of input voltage and provide long-term reliable DC voltage to the PV system.

  7. Study of a loss of feedwater transient for an integral pressurized water reactor with a helical coil steam generator

    International Nuclear Information System (INIS)

    The Multi-Application Small Light Water Reactor (MASLWR) is a system-level test facility constructed by Oregon State University to examine the thermal hydraulic phenomena that are of importance to integral pressurized water reactors (IPWRs). These phenomena include natural circulation instability, helical coil steam generator (HCSG) heat transfer and coupled reactor-containment pressurization. In MASLWR, the steam generator, the pressurizer and the reactor coolant system are integrated in one reactor pressure vessel unit and a metal slab is used to conduct the heat transfer between the containment vessel and the cooling pool. MASLWR is a scaled model of the NuScale design, a small modular reactor (SMR), with 1:3 length scale, 1:254 volume scale, 1:1 time scale, and full operating pressure and temperature. An IAEA International Collaborative Standard Problem (ICSP) was conducted using MASLWR to generate experimental data for various natural circulation conditions. In the ICSP, two experiments were conducted – “Loss of feedwater transient with subsequent automatic depressurization system operation” and “Normal operating conditions at different power levels”. US Nuclear Regulatory Commission participated in this standard problem in order to validate the TRACE MASLWR model and to identify any potential challenges to the code in simulating this unique design. The aim of the study is to support the future licensing review of the NuScale-like integral reactor design. In this paper, the loss of feedwater transient simulation will be discussed. The modeling strategy for the IPWR's unique components, such as the helical coil steam generator and the coupled reactor and containment, will be described in details. TRACE results show qualitative agreement with the experimental data in the major parameters of interest. However, one important event time of the calculation - the pressure equalization between the reactor and the containment - deviates from the data

  8. Investigation of a possible emergency procedure for the VVER-1000 NPP in case of total loss of feedwater and a main steam line break

    Energy Technology Data Exchange (ETDEWEB)

    Muellner, N. [Institute for Risk Research, University of Vienna, Wien (Austria); Giannotti, W.; D' Auria, F. [DIMNP, University of Pisa, Pisa (Italy)

    2004-07-01

    Accident management procedures associated with nuclear power plant beyond design basis accidents should be developed with the aid of the more recent versions of advanced computational tools (best estimate codes) in order to verify the effectiveness of normal operation systems of the plant to avoid or minimize core damage. A. Madeira showed in her paper 'A PWR Recovery Option for a Total Loss of Feedwater Beyond Design Basis Scenario' that it is possible to safely control a total loss of feedwater scenario in the Angra-2 nuclear power plant, using two emergency procedures, namely the opening of the steam generator (SG) relief valves, and on the primary side the complete manual opening of all pressurizer relief and safety valves. This paper investigates the effectiveness of the procedure opening of the SG relief valves, followed by primary side feed and bleed for a generic VVER-1000 NPP in case of a total loss of feed water. The results indicate that the procedure is successful in reducing the primary side pressure and temperature to safe conditions, it means that long term core cooling is achievable. (authors)

  9. Orthodontic springs and auxiliary appliances: assessment of magnetic field interactions associated with 1.5 T and 3 T magnetic resonance systems

    International Nuclear Information System (INIS)

    The objective of this paper is to evaluate magnetic field interactions at 1.5 and 3 T for 20 orthodontic devices used for fixed orthodontic therapy. Twenty springs and auxiliary parts made from varying ferromagnetic alloys were tested for magnetic field interactions in the static magnetic field at 1.5 and 3 T. Magnetic translational force Fz (in millinewtons) was evaluated by determining the deflection angle β [American Society for Testing and Materials (ASTM standard test method)]. Magnetic-field-induced rotational force Frot was qualitatively determined using a five-point scale. β was found to be >45 in 13(15) devices at 1.5(3) T and translational force Fz exceeded gravitational force Fg on the particular object [Fz 10.17-261.4 mN (10.72-566.4 mN) at 1.5(3) T]. Fz was found to be up to 24.1(47.5)-fold higher than Fg at 1.5(3) T. Corresponding to this, Frot on the objects was shown to be high at both field strengths (≥ +3). Three objects (at 1.5 T) and one object (at 3 T) showed deflection angles rot was found to be ≥ +3 at both field strengths. For the remaining objects, β was below 45 and torque measurements ranged from 0 to +2. Of 20 objects investigated for magnetic field interactions at 1.5(3) T, 13(15) were unsafe in magnetic resonance (MR), based on the ASTM criteria of Fz. The implications of these results for orthodontic patients undergoing MRI are discussed. (orig.)

  10. Orthodontic springs and auxiliary appliances: assessment of magnetic field interactions associated with 1.5 T and 3 T magnetic resonance systems

    Energy Technology Data Exchange (ETDEWEB)

    Kemper, J.; Priest, A.N.; Adam, G. [University Medical Center of Hamburg-Eppendorf, Clinic of Diagnostic and Interventional Radiology, Hamburg (Germany); Schulze, D. [University Hospital of Freiburg, Department of Oral and Maxillofacial Surgery, Freiburg (Germany); Kahl-Nieke, B.; Klocke, A. [University Medical Center of Hamburg-Eppendorf, Department of Orthodontics, Hamburg (Germany)

    2007-02-15

    The objective of this paper is to evaluate magnetic field interactions at 1.5 and 3 T for 20 orthodontic devices used for fixed orthodontic therapy. Twenty springs and auxiliary parts made from varying ferromagnetic alloys were tested for magnetic field interactions in the static magnetic field at 1.5 and 3 T. Magnetic translational force F{sub z} (in millinewtons) was evaluated by determining the deflection angle {beta} [American Society for Testing and Materials (ASTM standard test method)]. Magnetic-field-induced rotational force F{sub rot} was qualitatively determined using a five-point scale. {beta} was found to be >45 in 13(15) devices at 1.5(3) T and translational force F{sub z} exceeded gravitational force F{sub g} on the particular object [F{sub z} 10.17-261.4 mN (10.72-566.4 mN) at 1.5(3) T]. F{sub z} was found to be up to 24.1(47.5)-fold higher than F{sub g} at 1.5(3) T. Corresponding to this, F{sub rot} on the objects was shown to be high at both field strengths ({>=} +3). Three objects (at 1.5 T) and one object (at 3 T) showed deflection angles <45 , but F{sub rot} was found to be {>=} +3 at both field strengths. For the remaining objects, {beta} was below 45 and torque measurements ranged from 0 to +2. Of 20 objects investigated for magnetic field interactions at 1.5(3) T, 13(15) were unsafe in magnetic resonance (MR), based on the ASTM criteria of F{sub z}. The implications of these results for orthodontic patients undergoing MRI are discussed. (orig.)

  11. 47 CFR 73.1675 - Auxiliary antennas.

    Science.gov (United States)

    2010-10-01

    ... Class A TV licensees may request a decrease from the authorized facility's ERP in the license application. An FM, TV or Class A TV licensee may also increase the ERP of the auxiliary facility in a license... licensed main facility as an auxiliary facility with an ERP less than or equal to the ERP specified on...

  12. The centralized monitoring system solution for auxiliary equipment and environmental facilities in the station operation%厂站运行辅助设备及环境设备的集中监测系统解决方案

    Institute of Scientific and Technical Information of China (English)

    张振华

    2013-01-01

    With the gradual expansion of power system construction, unattended substation is imperative. The number and type of auxiliary equipment and environmental equipment in station operation are relatively large, so to realize the efficient and centralized monitoring and management of the equipment bears the brunt of difficulties. A new solution of plant station running auxiliary equipment and environmental equipment for centralized monitoring system is designed and proposed based on the relative switch information of automatic control and new sensing technology collect equipment. The system realizes centralized monitoring and management on auxiliary equipment and environment in the station operation by the dispatching terminal, after the communication network of electric power and the internal information network sent back the running state data of auxiliary equipment and environmental equipment in the station operation, which not only greatly improves the quality and efficiency of the equipment operation and maintenance, but also provides a new solution for substation communication network operation and maintenance. It can effectively realize unmanned operation and development of substation.%随着电力系统建设规模日趋壮大,变电站无人化已势在必行。厂站运行辅助设备、环境设备的数量和类型均相对较多,实现设备的高效、集中监控管理便成为了首当其冲的难题。基于自动控制和新型传感技术采集设备的相关开关量信息,设计并提出了一种新型的厂站运行辅助设备及环境设备的集中监测系统解决方案。该方案通过电力通信网和内部信息网络完成厂站运行辅助设备及环境设备运行状态数据的回传,从而实现了地调主站端对厂站运行的辅助设备和环境的集中实时监控和管理,极大地提高了设备运行维护的质量和效率。该研究为今后变电站通信网络的运行和维护提供了一种新的解决

  13. Evaluation of the applicability of amines as feed-water control reagents in terms of equilibrium water chemistry

    International Nuclear Information System (INIS)

    All Volatile Treatment (AVT), using ammonia and hydrazine, has been employed in Japan to control the pH of PWR secondary water. However, this treatment may become less effective at high temperatures. In recent years, new methods for controlling pH values have been studied overseas. One such method in high-pH control, which employs high-concentration ammonia solution. Other methods involve treatment with organic chemicals such as ethanolamine (ETA) and dimethylamine (DMA). It is important to evaluate the pH control effects of these new treatments. The purpose of this study was to evaluate the effect of these treatments on pH control and on mitigation of iron and copper oxides transportation into a PWR secondary water system. The main results are as follows: 1. High-pH control treatment can decrease the transportation of iron oxide in both feed-water and drainage-water systems. However, it is necessary to exclude copper alloys and to devise methods for decreasing the condensate demineralizer load. 2. ETA treatment appears to be more effective in mitigating the transportation of iron and copper oxides than the conventional AVT treatment. ETA treatment is the most effective method for pH control, particularly in drainage-water system. (author)

  14. 多方式辅助加热太阳能集中供热水远程监测系统%Remote Multi-way Auxiliary Heating Monitoring System for Solar Central Heating

    Institute of Scientific and Technical Information of China (English)

    田志宏; 任立鹏; 董智

    2016-01-01

    在对太阳能供热水系统特点及空气源热泵工作原理进行研究的基础上,设计了以空气源热泵和电加热器为辅助热源的太阳能集中供热水远程监测系统,不仅解决了太阳能供热水系统单一热源的局限性问题,同时也实现了远程实时监测。以天津某高校培训中心采用的太阳能供热系统为例,结合当地气候,计算了工程需要的集热器面积和空气源热泵机组数量,详细介绍了采用模块化设计方法开发远程监测系统的过程,并与原天然气供热水系统的水、电和天然气实测消耗量进行了对比。结果表明,多方式辅助加热太阳能集中供热水系统的综合运行费用明显降低,具有较高的应用价值。%Based on the research of the characteristics of solar water heating systems and the working principle of air-source heating pump,a remote monitoring system for solar heating was designed,using air source heating pump and electric heater as the auxiliary heat source.It can not only solve the problem of the limitation of the solar heating system due to single heat-ing source,but also realize the remote and real-time monitoring of the solar water heating system.Taking the solar energy project of a university training center in Tianjin as an example,the required collector area and air source heating pump units were calculated against the local climate.The process of developing a remote monitoring system with modular designs was described in detail,and the actual consumption of water,electricity and natural gas were measured and compared with the natural gas heating system.The results show that the total operation cost of the multi-way auxiliary heating system is obvi-ously reduced,and the system is of higher value in application.

  15. Feed-water heaters alternative design comparison; Comparacion de disenos alternativos de calentadores

    Energy Technology Data Exchange (ETDEWEB)

    Torres Toledano, Gerardo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    A procedure is presented for the alternative design comparison of feed water heaters, based in the failure records of damaged tubes during operation. The procedure is used for cases in which non-continuous or random inspections are made to the feed-water heaters. [Espanol] Se presenta un procedimiento para comparar disenos alternativos de calentadores, basandose en los registros de fallas de los tubos rotos acumuladas durante su operacion. El procedimiento se emplea para casos en los que se realizan inspecciones a los calentadores no continuas, ya sea periodicas o al azar.

  16. 49 CFR 230.57 - Injectors and feedwater pumps.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and... delivery systems required. Each steam locomotive must be equipped with at least two means of delivering water to the boiler, at least one of which is a live steam injector. (b) Maintenance and...

  17. Key issues of oxygenated feed-water treatment for supercritical boiler%超临界锅炉给水加氧的关键问题

    Institute of Scientific and Technical Information of China (English)

    艾志虎; 刘定平

    2011-01-01

    The oxygenated feed-water treatment technology of supercritical boiler could effectively decrease the internal corrosion and leposition rate from the water condensation system to the boiler water feeding system.The steam-water quality and the operating efficiency of supercritical units are greatly promoted .Combined with the different feed-water operation modes in the supercritical power currently,the features of the operational ways and the fundamental principles have been described.The key issues in oxygenated treatment(OT)for feed-water of supercritical units were researched.Based on an accurate and reliable adding oxygen system,the precise oxygen feeding amount and the strict transistion conditions between AVT and OT,the effective implementation of the oxygenated treament has been proposed so as to provide a useful reference to popularized the technique of oxygen addition for the supercritical electricity generation units.%超临界锅炉给水加氧处理技术可以有效降低机组凝结水至炉水系统管内的腐蚀及沉积速率,提高汽水品质和机组运行效率.结合当前超临界锅炉不同的给水运行方式,阐述了给水加氧特点和基本原理;针对当前困扰超临界锅炉给水加氧技术应用的关键问题进行研究,提出了有效实施给水加氧技术必须选择正确可靠的加氧系统、把握精确的氧质量分数控制和严格控制全挥发性处理与给水加氧处理方式相互转换条件等关键环节,可为给水加氧技术在大型超临界火力发电机组的推广应用提供指导.

  18. Analysis of the Pactel loss-of-feedwater experiments

    Energy Technology Data Exchange (ETDEWEB)

    Korteniemi, V.; Virtanen, E.; Haapalehto, T. [Lappeenranta Univ. of Technology (Finland); Kouhia, J. [VTT Energy, Espoo (Finland). Nuclear Energy

    1995-12-31

    The western thermal-hydraulic system codes, like RELAP5 and CATHARE2, are developed and validated to model the phenomena in the vertical steam generators. The differences between vertical and horizontal steam generators are so significant that the calculational models developed for the vertical steam generators are not directly applicable for the horizontal steam generators. The PACTEL loss of feed water experiments have been performed to study the overall behaviour of the horizontal steam generators and especially to produce experimental data for code assessment. In this paper the results from APROS, CATHARE2 and RELAP5 calculations of a series of experiments are presented. 6 refs.

  19. Participation of Empresarios Agrupados in engineering of the Tokamak systems and auxiliary buildings; Participacion de Empresarios Agrupados en la Ingenieria de los sistemas de tokamak y edificios auxiliares

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez del Palacio, V.

    2013-07-01

    The Architect Engineering works comprise approximately the design of 32 buildings and structures, some of them very simple and others extremely complex. 32 buildings include nuclear buildings, as the Toyama, tritium, or the building of emergency diesel and buildings conventional and the building of the site services. Systems including those related to systems within a building they reach conventional, while interfaces with process systems are countless. Grouped entrepreneurs led the design of the mechanical (PBS65) systems and Electric (PBS43) actively participating in the design of systems of fire proofing of buildings and site. During the development of engineering accident of Fukushima works directly affect in the design of the systems.

  20. Evaluation of erosion corrosion damage of the original WWER 440 steam generator feedwater piping

    International Nuclear Information System (INIS)

    The effects of erosion corrosion on WWER 440 steam generator feedwater piping were evaluated by using the CHECMATE code (EPRI), involving data of temperature of the medium, Cr, Mo, and Cu contents of the steel, medium flow, component geometry, liquid and gaseous fractions of the medium, pH, and oxygen content of the medium. The assessment was performed for the Dukovany NPP. It was concluded that in view of the relatively low corrosion damage rate, additional development of corrosion defects will not be caused by erosion. The development of defects observed on the T-piece may be due to a combined effect of erosion and corrosion in points where additional corrosion takes place in defects that had developed before. The degradation mechanism causing a further development of existing defects seems to consist in the corrosion effect of the aqueous medium in operating conditions. The additional development of defects of the feedwater piping is a serious finding requiring adequate provisions. 4 tabs., 7 figs., 2 refs

  1. Quantum Entanglement of Two Flux Qubits Induced by an Auxiliary SQUID

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We revisit a theoretical scheme to create quantum entanglement of two three-level superconducting quantum interference devices (SQUIDs) with the help of an auxiliary SQUID. In this scenario, two three-level systems are coupled to a quantized cavity field and a classical external field and thus form dark states. The quantum entanglement can be produced by a quantum measurement on the auxiliary SQUID. Our investigation emphasizes the quantum effect of the auxiliary SQUID. For the experimental feasibility and accessibility of the scheme, we calculate the time evolution of the whole system including the auxiliary SQUID. To ensure the efficiency of generating quantum entanglement, relations between the measurement time and dominate parameters of the system are analyzed according to detailed calculations.

  2. Robust video transmission with distributed source coded auxiliary channel.

    Science.gov (United States)

    Wang, Jiajun; Majumdar, Abhik; Ramchandran, Kannan

    2009-12-01

    We propose a novel solution to the problem of robust, low-latency video transmission over lossy channels. Predictive video codecs, such as MPEG and H.26x, are very susceptible to prediction mismatch between encoder and decoder or "drift" when there are packet losses. These mismatches lead to a significant degradation in the decoded quality. To address this problem, we propose an auxiliary codec system that sends additional information alongside an MPEG or H.26x compressed video stream to correct for errors in decoded frames and mitigate drift. The proposed system is based on the principles of distributed source coding and uses the (possibly erroneous) MPEG/H.26x decoder reconstruction as side information at the auxiliary decoder. The distributed source coding framework depends upon knowing the statistical dependency (or correlation) between the source and the side information. We propose a recursive algorithm to analytically track the correlation between the original source frame and the erroneous MPEG/H.26x decoded frame. Finally, we propose a rate-distortion optimization scheme to allocate the rate used by the auxiliary encoder among the encoding blocks within a video frame. We implement the proposed system and present extensive simulation results that demonstrate significant gains in performance both visually and objectively (on the order of 2 dB in PSNR over forward error correction based solutions and 1.5 dB in PSNR over intrarefresh based solutions for typical scenarios) under tight latency constraints.

  3. Orbiter Auxiliary Power Unit Flight Support Plan

    Science.gov (United States)

    Guirl, Robert; Munroe, James; Scott, Walter

    1990-01-01

    This paper discussed the development of an integrated Orbiter Auxiliary Power Unit (APU) and Improved APU (IAPU) Flight Suuport Plan. The plan identifies hardware requirements for continued support of flight activities for the Space Shuttle Orbiter fleet. Each Orbiter vehicle has three APUs that provide power to the hydraulic system for flight control surface actuation, engine gimbaling, landing gear deployment, braking, and steering. The APUs contain hardware that has been found over the course of development and flight history to have operating time and on-vehicle exposure time limits. These APUs will be replaced by IAPUs with enhanced operating lives on a vehicle-by-vehicle basis during scheduled Orbiter modification periods. This Flight Support Plan is used by program management, engineering, logistics, contracts, and procurement groups to establish optimum use of available hardware and replacement quantities and delivery requirements for APUs until vehicle modifications and incorporation of IAPUs. Changes to the flight manifest and program delays are evaluated relative to their impact on hardware availability.

  4. Comparison of single phase self excited induction generator excitation configurations using the main and auxiliary windings for a micro hydro system

    Energy Technology Data Exchange (ETDEWEB)

    Oh, T.; Freere, P. [Kathmandu Univ. (Nepal). Dept. of Electrical and Electronic Engineering

    2005-07-01

    Induction generators are one of the most popular generators for micro hydro systems. Three phase generators are often used even though only a single phase supply is needed. This paper investigates the characteristics of single phase induction generators. Many different winding and excitation capacitor configurations are investigated. To use these generators effectively, the desired output should be near the rated power and voltage. This paper includes laboratory test and simulation results. (Author)

  5. Builtin vs. auxiliary detection of extrapolation risk.

    Energy Technology Data Exchange (ETDEWEB)

    Munson, Miles Arthur; Kegelmeyer, W. Philip,

    2013-02-01

    A key assumption in supervised machine learning is that future data will be similar to historical data. This assumption is often false in real world applications, and as a result, prediction models often return predictions that are extrapolations. We compare four approaches to estimating extrapolation risk for machine learning predictions. Two builtin methods use information available from the classification model to decide if the model would be extrapolating for an input data point. The other two build auxiliary models to supplement the classification model and explicitly model extrapolation risk. Experiments with synthetic and real data sets show that the auxiliary models are more reliable risk detectors. To best safeguard against extrapolating predictions, however, we recommend combining builtin and auxiliary diagnostics.

  6. Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Esparza Gutierrez, Rogelio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in order to control the performance, compare them among similar units and power stations, and inclusively verify possible recurrent causes of low availability in the referred systems. [Espanol] En este articulo se presenta la metodologia seguida para diagnosticar el comportamiento de equipos en los que se transfiere calor de los sistemas de agua de alimentacion, condensado y circulacion de las centrales termoelectricas (CTE). La toma de datos se realiza con la unidad en operacion normal, utilizando instrumentacion local sin necesidad de sacar de servicio a los equipos para su instalacion, ya que se ocupan los mismos puntos para instrumentos con que cuentan por diseno. El diagnostico de los equipos se realiza mediante el analisis de los datos recopilados, tanto de operacion real como de diseno; para ello, se efectua un balance termico de los sistemas de interes para obtener todas las condiciones y los datos de operacion. Posteriormente, se calculan los parametros indicativos de

  7. Threshold concentration of easily assimilable organic carton in feedwater for biofouling of spiral-wound membranes.

    Science.gov (United States)

    Hijnen, W A M; Biraud, D; Cornelissen, E R; van der Kooij, D

    2009-07-01

    One of the major impediments in the application of spiral-wound membranes in water treatment or desalination is clogging of the feed channel by biofouling which is induced by nutrients in the feedwater. Organic carbon is, under most conditions, limiting the microbial growth. The objective of this study is to assess the relationship between the concentration of an easily assimilable organic compound such as acetate in the feedwater and the pressure drop increase in the feed channel. For this purpose the membrane fouling simulator (MFS) was used as a model for the feed channel of a spiral-wound membrane. This MFS unit was supplied with drinking water enriched with acetate at concentrations ranging from 1 to 1000 microg C x L(-1). The pressure drop (PD) in the feed channel increased at all tested concentrations but not with the blank. The PD increase could be described by a first order process based on theoretical considerations concerning biofilm formation rate and porosity decline. The relationship between the first order fouling rate constant R(f) and the acetate concentration is described with a saturation function corresponding with the growth kinetics of bacteria. Under the applied conditions the maximum R(f) (0.555 d(-1)) was reached at 25 microg acetate-C x L(-1) and the half saturation constant k(f) was estimated at 15 microg acetate-C x L(-1). This value is higher than k(s) values for suspended bacteria grown on acetate, which is attributed to substrate limited growth conditions in the biofilm. The threshold concentration for biofouling of the feed channel is about 1 microg acetate-C x L(-1).

  8. Generating Selected Color using RGB, Auxiliary Lights, and Simplex Search

    Directory of Open Access Journals (Sweden)

    Kim HyungTae

    2015-01-01

    Full Text Available A mixed light source generates various colors, with the potential to adjust intensities of multiple LEDs, which makes it possible to generate arbitrary colors. Currently, PCs and OSs provide color selection windows that can obtain the RGB or HSL color coordinates of a user’s selection. Mixed light sources are usually composed of LEDs in the primary colors, with LEDs in auxiliary colors such as white and yellow used in a few cases. When using auxiliary color LEDs, the number of LED inputs, the dimming levels, is larger than the number of elements in the color coordinate, which causes an under-determined problem. This study proposed how to determine the dimming levels of LEDs based on the selected color. Commercial LEDs have di_erent optical power values and impure color coordinates, even if they are RGB. Hence, the characteristics of the LEDs were described using a linear model derived from the tri-stimulus values (an XYZ color coordinate model and dimming levels. Color mixing models were derived for the arbitrary number of auxiliary color LEDs. The under-determined problem was solved using a simplex search method without an inverse matrix operation. The proposed method can be applied to a machine vision system and an RGBW light mixer for semiconductor inspection. The dimming levels, obtained using the proposed method were better than derived using other methods.

  9. Transport in Auxiliary Heated NSTX Discharges

    International Nuclear Information System (INIS)

    The NSTX spherical torus (ST) provides a unique platform to investigate magnetic confinement in auxiliary-heated plasmas at low aspect ratio. Auxiliary power is routinely coupled to ohmically heated plasmas by deuterium neutral-beam injection (NBI) and by high-harmonic fast waves (HHFW) launch. While theory predicts both techniques to preferentially heat electrons, experiment reveals the electron temperature is greater than the ion temperature during HHFW, but the electron temperature is less than the ion temperature during NBI. In the following we present the experimental data and the results of transport analyses

  10. Analysis on Improvement of Lightning Protection of Nuclear Auxiliary Building Ventilation System of LING AO PhaseⅡ%岭澳二期核辅助厂房通风系统防雷改进分析

    Institute of Scientific and Technical Information of China (English)

    李明钢; 王耀刚; 李东; 关济实; 张立蕊

    2016-01-01

    Affected by climate, it is always raining in Guang Dong province and the Daya bay nuclear power plant always suffers from lightning. Therefore, it is very important to improve the lightning protection facilities. In order to solve the problems that lightning protection of nuclear auxiliary building ventilation system and other related component in Daya bay nuclear power plant reactor protection system, and improve the lightning protection level, a plan about improving the lightning protection facilities is proposed, and further analysis and demonstration are made as well, which are based on the actual situation. The plan of improving the lightning protection facilities is of great significance to the safe and stable operation of Daya bay nuclear power station.%受气候影响,广东大亚湾核电站多发雷雨,而雷击会严重威胁核电站的安全稳定运行。因此,提高防雷设施十分重要。针对大亚湾核电站反应堆保护系统相关的核辅助厂房通风系统的信号回路结构及容易受到雷电干扰部分的防雷保护问题,结合实际情况,对核辅助厂房通风系统的防雷设施进行改进及分析论证,提高防雷等级。该防雷设施改进方案对大亚湾核电站的安全稳定运行有着重要的意义。

  11. New energy conversion processes and neglected auxiliary systems - a treasure trove for energy service providers; Neue Techniken und vernachlaessigte Nebenanlagen - eine Fundgrube fuer Energiedienstleister

    Energy Technology Data Exchange (ETDEWEB)

    Jochem, E.

    1998-12-31

    The paper shows that apart from the risks, the deregulation of the energy sector also offered new chances, which recently materialized in three emerging independent trends, initiating innovative approaches for energy conversion and applications and demand for new knowledge-based, near-production energy services as a new field for engineers: Providers of energy efficiency-related technology widen their capabilities by adding the new business segment of energy service marketing. Industrial energy users more strongly consider outsourcing of energy conversion systems and the relevant contracting schemes as an option for reducing energy costs. Public enterprise as energy users started following this trend, all the more as insufficient financial resources do not permit them to reinvest. The paper discusses the conversion processes which currently open up promising chances for energy service producers. (orig./CB) [Deutsch] Neben Gefahren, die inhaerentes Merkmal der Liberalisierung sind, zeichnen sich drei unabhaengige Entwicklungen ab, die innovative Initiativen in der Energiewandlung und -nutzung staerken und wissensintensive produktionsnahe Dienstleistungen als zentrale Aufgabe fuer den Ingenieur initieren: - Die Energieeffizienz-Technologieanbieter nehmen die Energiedienstleistungen in ihre Angebotspalette auf. - Die betrieblichen Energieanwender beginnen zunehmend, ueber das Outsourcing energiewandelnder Anlagen Energiekosten zu senken. - Die oeffentliche Hand als Energieanwender beginnt aehnlich zu denken, zumal sie infolge der hohen Verschuldung unzureichende finanzielle Mittel fuer Reinvestitionen hat. Hierueber sei kurz berichtet, bevor auf die Techniken eingegangen wird, die sich besonders aus heutiger Sicht fuer Energiedienstleister eignen. (orig./RHM)

  12. 基于Android的移动公交辅助导航系统设计与实现%Design and Implementation of Mobile Bus Auxiliary Navigation System Based on Android

    Institute of Scientific and Technical Information of China (English)

    文斌; 李代伟

    2012-01-01

    Based on the Android mobile development platform, a bus auxiliary navigation system, is designed. The paper proposes a system solution based on the Android Operate System, combined with SQLite database and Baidu maps Application Programming Interface, real-time location of the user's current location through Global Positioning System. This method helps to finish the bus lines and site inquiries and travel line planning, and so on. It includes off-line inquiries and online query, and meets the user in different situations to complete public transport inquiries and route planning. In the meantime, we creatively came up with two more efficient algorithms, which are non-stop search algorithm based on the bus lines and the Bus Stop, and change bus search algorithm based on the non-stop bus lines and the bus stop. The experimental results show that the system can run on mobile devices based on the Android system, and it is easy for users to travel.%基于Android移动开发平台,设计一款公交辅助导航软件系统.基于Android操作系统,结合SQLite数据库和百度地图应用程序编程接口,通过全球定位系统实时定位用户当前位置,完成公交线路查询、公交站点查询、出行线路规划等功能.同时,包括离线查询和在线查询,能满足用户在不同情况下完成公交信息查询和路线规划.创新性地提出了效率较高的“基于线路与站点的直达车搜索算法”、“基于直达车线路和站点的换乘车搜索算法”.实验结果表明,系统能运行于基于Android系统的移动设备,为用户出行带来方便.

  13. X射线成像系统辅助设备的研发与应用%Development and application on auxiliary equipment of X-ray imaging system

    Institute of Scientific and Technical Information of China (English)

    马飞越; 王博

    2015-01-01

    Because the installation position of vertical layout switching equipments including GIS (gas insulated switch gear) equipment,tank circuit-breaker and live tank circuit-breaker are higher,the function at height and angle of the X-ray imaging system equipment cannot meet the imaging inspection requirements. The paper developes a height and angle adjustable and mobile X-ray imaging auxiliary equipment,and successfully applies to X-ray imaging inspection of 330 kV live tank circuit-breaker. The application result shows that the device not only improves the efficiency of x-ray imaging inspection,but also ensures the safety of test staff,provides help for the application and popularization of X-ray imaging inspection technology.%由于垂直布置的GIS设备、罐式断路器及瓷柱式断路器等开关类设备安装位置较高,现有X射线成像系统自带辅助装置在高度和角度上不能满足现场X射线成像检测需求。本文开发了一种高度、角度可调的移动式X射线成像系统辅助设备,并成功应用于330 kV瓷柱式断路器X射线成像检测中。应用结果表明:该装置不仅提高了X射线成像检测的效率,而且保证了试验人员安全性,为X射线成像检测技术的推广应用提供了帮助。

  14. Curricular Guidelines for Dental Auxiliary Radiology.

    Science.gov (United States)

    Journal of Dental Education, 1981

    1981-01-01

    AADS curricular guidelines suggest objectives for these areas of dental auxiliary radiology: physical principles of X-radiation in dentistry, related radiobiological concepts, principles of radiologic health, radiographic technique, x-ray films and intensifying screens, factors contributing to film quality, darkroom, and normal variations in…

  15. Geostatistical modeling of topography using auxiliary maps

    NARCIS (Netherlands)

    T. Hengl; B. Bajat; D. Blagojević; H.I. Reuter

    2008-01-01

    This paper recommends computational procedures for employing auxiliary maps, such as maps of drainage patterns, land cover and remote-sensing-based indices, directly in the geostatistical modeling of topography. The methodology is based on the regression-kriging technique, as implemented in the R pa

  16. Study of the Household Solar Energy Biogas Digester System with Auxiliary Electric Heater%户用辅助加热式太阳能沼气池系统研究

    Institute of Scientific and Technical Information of China (English)

    崔俊奎; 陈文婷

    2012-01-01

    Due to the low temperature in winter, the biogas fermentation being influenced, the gas production will decrease,or there may produce no biogas, which seriously restricts the application and development of bio-gas digesters. The solar energy biogas digester causes more and more concern and attention, solar collectors only operates during the sunlight in the daytime. The household solar energy biogas digester system with auxiliary electric heater was put forward to ensure efficient operation. The composition and working principle of the system were explained, the two-dimensional steady numerical simulation of heating process in biogas digesters were carried on by using computational fluid dynamics(CFD),the multi-reference frame(MRF)and standard k-ε turbulent model. At the same time,experimental observation was made to validate the rationality of the system. Finally, the feasibility of the system was explained from an economic point of view.%北方地区冬季温度较低出现沼气池产气量少甚至不产气的问题,严重制约着沼气池在农村的应用与推广,逐渐兴起的太阳能沼气池法受到人们的关注和重视。由于太阳能集热器只能在有日照的白天进行储能,为保证沼气池正常连续高效的运行,一种舍辅助电加热器的户用太阳能沼气池系统被提出,文章介绍了系统的组成和工作原理,根据k-ε湍流模型与相应的计算网络及边界条件对沼气池进行了二维定常数值仿真,并进行了实验观测从而验证了该系统的合理性。最后又从经济角度阐述了它的可行性。

  17. 基于模糊规则提升理论的马病辅助诊断专家系统%Equine diseases auxiliary diagnosis expert system based on fuzzy rule promotion theory

    Institute of Scientific and Technical Information of China (English)

    秦宏宇; 李建新; 高翔; 王欢; 肖建华; 王洪斌

    2016-01-01

    approach for providing the intelligence in the system for diagnosis of the equine diseases. This experiment was conducted to develop a remote auxiliary equine diseases diagnosis expert system. By collecting and analyzing the experiences of diagnosis and treatment from experts on equine disease, the numerical expression of the equine diseases diagnosis knowledge was developed. The knowledge of equine diseases was represented with the method called object-attribute-value triples act (referred as O-A-V act) that combined with the generative formula. As such, it was easy to extract knowledge rules and these rules were used for inference mechanism. Using the confidence factor, multi-valued logic was used to represent the rules of confidence level. In this paper, we suggested a new inference method which was based on use of a fuzzy rule promotion theory. This approach can enhance the intelligence of the disease diagnosis system. If a rule was repeatedly used in corrective diagnostic results, it was then promoted to a higher confidence factor by the rule promotion factor (PCF), and the PCF was the original confidence factor in the next diagnosis session. In short, the dynamic PCF which was generated in the past dialogue was used instead of static CF in the final decision making process. The dynamically promoted rules were derived from those diagnosis sessions, which resulted in successful decisions. This enabled more efficient decision making in the future sessions. With this approach, it was not only decreasing the number of interactive between the system and the users, but also leading to acceptable diagnostic results. Based on the research of knowledge representation and inference mechanism, an auxiliary diagnostic expert system of equine diseases based on Microsoft.Net and SQL Server 2008 was designed and developed. It provided online help to equine farmers and extension workers in China. For the inference engine of system, we used the fuzzy rule promotion methodology that

  18. Review of industry efforts to manage pressurized water reactor feedwater nozzle, piping, and feedring cracking and wall thinning

    International Nuclear Information System (INIS)

    This report presents a review of nuclear industry efforts to manage thermal fatigue, flow-accelerated corrosion, and water hammer damage to pressurized water reactor (PWR) feedwater nozzles, piping, and feedrings. The review includes an evaluation of design modifications, operating procedure changes, augmented inspection and monitoring programs, and mitigation, repair and replacement activities. Four actions were taken: (a) review of field experience to identify trends of operating events, (b) review of technical literature, (c) visits to PWR plants and a PWR vendor, and (d) solicitation of information from 8 other countries. Assessment of field experience is that licensees have apparently taken sufficient action to minimize feedwater nozzle cracking caused by thermal fatigue and wall thinning of J-tubes and feedwater piping. Specific industry actions to minimize the wall-thinning in feedrings and thermal sleeves were not found, but visual inspection and necessary repairs are being performed. Assessment of field experience indicates that licensees have taken sufficient action to minimize steam generator water hammer in both top-feed and preheat steam generators. Industry efforts to minimize multiple check valve failures that have allowed backflow of steam from a steam generator and have played a major role in several steam generator water hammer events were not evaluated. A major finding of this review is that analysis, inspection, monitoring, mitigation, and replacement techniques have been developed for managing thermal fatigue and flow-accelerated corrosion damage to feedwater nozzles, piping, and feedrings. Adequate training and appropriate applications of these techniques would ensure effective management of this damage

  19. Review of industry efforts to manage pressurized water reactor feedwater nozzle, piping, and feedring cracking and wall thinning

    Energy Technology Data Exchange (ETDEWEB)

    Shah, V.N.; Ware, A.G.; Porter, A.M.

    1997-03-01

    This report presents a review of nuclear industry efforts to manage thermal fatigue, flow-accelerated corrosion, and water hammer damage to pressurized water reactor (PWR) feedwater nozzles, piping, and feedrings. The review includes an evaluation of design modifications, operating procedure changes, augmented inspection and monitoring programs, and mitigation, repair and replacement activities. Four actions were taken: (a) review of field experience to identify trends of operating events, (b) review of technical literature, (c) visits to PWR plants and a PWR vendor, and (d) solicitation of information from 8 other countries. Assessment of field experience is that licensees have apparently taken sufficient action to minimize feedwater nozzle cracking caused by thermal fatigue and wall thinning of J-tubes and feedwater piping. Specific industry actions to minimize the wall-thinning in feedrings and thermal sleeves were not found, but visual inspection and necessary repairs are being performed. Assessment of field experience indicates that licensees have taken sufficient action to minimize steam generator water hammer in both top-feed and preheat steam generators. Industry efforts to minimize multiple check valve failures that have allowed backflow of steam from a steam generator and have played a major role in several steam generator water hammer events were not evaluated. A major finding of this review is that analysis, inspection, monitoring, mitigation, and replacement techniques have been developed for managing thermal fatigue and flow-accelerated corrosion damage to feedwater nozzles, piping, and feedrings. Adequate training and appropriate applications of these techniques would ensure effective management of this damage.

  20. Depressurization as an accident management strategy for Jose Cabrera nuclear plant loss of feedwater and station blackout events

    International Nuclear Information System (INIS)

    This paper reports on an evaluation of the efficiency of the operator initiated depressurization in the Spanish Westinghouse one loop Jose Cabrera nuclear power plant that has been developed. This operation is recommended in the present emergency procedure for the total loss of feedwater event in the bleed and feed mode. RELAP5/MOD2 analyses show that this is an effective measure to bring the plant to a cold and stable condition in a design-based accident scenario

  1. Effects of auxiliary source connections in multichip power module

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Beczkowski, Szymon;

    2016-01-01

    Auxiliary source bond wires and connections are widely used to in the power module with paralleled MOSFETs or IGBTs. This paper investigates the working mechanism and the effects of the auxiliary source connections in multichip power modules. It reveals that the auxiliary source connections cannot...

  2. Influence of the loop design of the feedwater- and steam quality in a power plant with pressurized water reactor

    International Nuclear Information System (INIS)

    At nuclear power plants with pressurized water reactors, condensate occurs on the high pressure part of the water-steam circuit, caused by the operation with low steam parameters. The behaviour of the electrolytes which entered into the circuit (solubility, distribution in water and/or steam) shows that these electrolytes (salts) are to be found mainly in the condensate. The insinuated electrolytes are reconcentrated during the common arrangements with 'Small Circuit' - consisting of steam generator, high pressure turbine, water separator, feedwater vessel, and have a negative influence on the feedwater - boiler water - and the steam quality. Remedy is possible by modified arrangements, during which these electrolyte-containing condensates will be treated and traced back into the main circuit. Nevertheless that the efficiency decrease is insignificant and additional efforts are necessary, a change over to these arrangements is recommendable, due to the fact that the feedwater quality, the boiler water quality, the steam quality in front of the turbine, and finally also the operational safety, as well as the availability will be improved. (orig.)

  3. Software design and implementation of GPS-based gun directing radar auxiliary guide system%基于GPS的炮瞄雷达辅助引导系统软件设计与实现

    Institute of Scientific and Technical Information of China (English)

    黄信安; 刘刚

    2014-01-01

    空空导弹研制过程需要进行一系列地面飞行试验,而炮瞄雷达为高精度跟踪雷达,波束很窄,不具备大范围自动搜索功能;在地面试验中,雷达跟踪过程出会现丢失目标无法引导的情况,构不成试验条件,导致试验无法进行;该软件利用靶机提供的GPS定位数据,实时解算目标方位、俯仰信息传输给炮瞄雷达系统,实现了对目标的辅助引导、对靶机飞行轨迹的记录回放、以及对目标方位修正功能;实际应用结果表明,该软件具有较高的可靠性和可扩展性,完全满足辅助引导系统的需要。%During the development process of air-to-air missile,a serial of flight test have to be done. The gun directing radar has high precision in tracking,bu its beam is narrow,so it does not have wide range of automatic search function. In ra-dar tracking procedure,the situation of target missing can stop the test. The software can calculate the target bearing and pitch information in real-time,then transmit it to gun directing radar system by using GPS locator data from target drone,thus to realize the functions of assisted guidance for the target,recording and playback of target drone flight trajectory,and the modification the target bearing. The practical application result shows that the software has high reliability and scalability,and can fully meet the needs of auxiliary and guide system.

  4. Modified Darboux transformations with foreign auxiliary equations

    International Nuclear Information System (INIS)

    We construct a new type of first-order Darboux transformations for the stationary Schroedinger equation. In contrast to the conventional case, our Darboux transformations support arbitrary (foreign) auxiliary equations. We show that among other applications, our formalism can be used to systematically construct Darboux transformations for Schroedinger equations with energy-dependent potentials, including a recent result (Lin et al., 2007) as a special case. -- Highlights: → We generalize the Darboux transformation for the Schroedinger equation. → By admitting arbitrary auxiliary functions, we provide a new tool for generating solutions. → As a special case we recover a recent result on energy-dependent potentials. → We extend the latter result to very general energy-dependence.

  5. Heterotopic Auxiliary Liver Transplantation with Portal Flow

    OpenAIRE

    Laureano Lorente; Jaime Arias; Maria Angeles Aller; José Ignacio Ispizua; José Rodriguez; Hipólito Durán

    1990-01-01

    One of the causes of auxiliary liver transplantation failure is the inter-liver competition between the host liver and the graft for the hepatotrophic factors of the portal blood. We have developed an experimental model of heterotopic partial (30%) liver isotransplant using Wistar rats so as to study this competition. Splenoportography and dissection demonstrate the existence of collateral circulation. The collaterals at 90 days post-transplant (PT) consisted of veins from the portal vein to ...

  6. Solar combisystems with forecast control to increase the solar fraction and lower the auxiliary energy cost

    DEFF Research Database (Denmark)

    Perers, Bengt; Furbo, Simon; Fan, Jianhua;

    2011-01-01

    Solar Combi systems still need quite a lot of auxiliary energy especially in small systems without seasonal storage possibilities. The control of the auxiliary energy input both in time and power is important to utilize as much as possible of the solar energy available from the collectors and also...... energy sources. It can be either direct electric heating elements or a heat pump upgrading ambient energy in the air, ground, solar collector or waste heat from the house. The paper describes system modeling and simulation results. Advanced laboratory experiments are also starting now with three...

  7. In-service inspection techniques for PWR steam generator feedwater and pressuriser nozzles

    International Nuclear Information System (INIS)

    Regular ultrasonic inspection of the steam generator feedwater and pressuriser nozzles of the Sizewell B Pressurised Water Reactor, under construction by the Central Electricity Generating Board (CEGB), will be carried out to detect and size any service-induced cracking in the nozzle corners and bores. External access only will be available for such inspections and, to achieve full inspection coverage, it may be necessary to scan probes under the outer blend radius and adjacent surfaces of each nozzle. As part of the PWR Safety Research Programme being conducted collaboratively by CEGB and the United Kingdom Atomic Energy Authority (UKAEA) in the UK, Risley Laboratories have been developing automated ultrasonic techniques to meet the stringent inspection standards demanded for these components. The geometrical complexity of the inspection has necessitated the use of mathematical modelling to optimise inspection techniques and coverage. Computer-based data collection, display and analysis methods have been developed for the combined pulse-echo and time-of-flight diffraction techniques selected for these inspections. In this paper, the development work performed at Risley is reviewed and examples of the application of the inspection techniques to simulated service-induced defects in full-scale test specimens presented. Work on the related problem of cracking in BWR nozzles (ref.1) has demonstrated detection capability but not accurate sizing. However sizing of defects in the nozzle corner areas has been achieved in this programme with the use of advanced reconstruction methods. (author)

  8. GEOTHERMAL / SOLAR HYBRID DESIGNS: USE OF GEOTHERMAL ENERGY FOR CSP FEEDWATER HEATING

    Energy Technology Data Exchange (ETDEWEB)

    Craig Turchi; Guangdong Zhu; Michael Wagner; Tom Williams; Dan Wendt

    2014-10-01

    This paper examines a hybrid geothermal / solar thermal plant design that uses geothermal energy to provide feedwater heating in a conventional steam-Rankine power cycle deployed by a concentrating solar power (CSP) plant. The geothermal energy represents slightly over 10% of the total thermal input to the hybrid plant. The geothermal energy allows power output from the hybrid plant to increase by about 8% relative to a stand-alone CSP plant with the same solar-thermal input. Geothermal energy is converted to electricity at an efficiency of 1.7 to 2.5 times greater than would occur in a stand-alone, binary-cycle geothermal plant using the same geothermal resource. While the design exhibits a clear advantage during hybrid plant operation, the annual advantage of the hybrid versus two stand-alone power plants depends on the total annual operating hours of the hybrid plant. The annual results in this draft paper are preliminary, and further results are expected prior to submission of a final paper.

  9. Dismantling and decontamination of the tube bundle of a feedwater preheater of the Garigliano BWR

    International Nuclear Information System (INIS)

    The report deals with dismantling and decontamination of the tube bundle of a feedwater preheater of Garigliano-BWR. Decontamination is a common practice in decommissioning works and it can be used both for reducing radiation exposures, in order to save manrem, and for the unrestricted release of materials. In this latter field the decontamination of tube bundle is a particular case because of their large contaminated surfaces and relatively low weight; at the moment no decon technique was available on the market to decontaminate up to the unrestricted release the materials of tube bundles. In this context an innovative decon technique using aggressive chemicals together with ultrasounds in a tank, was developed by several laboratories and assessed with in-scale testings. A decon procedure considering two phases: first with ultrasounds applied in water at 600C, and second with ultrasounds applied in a solution of HF/HNO3 acids at 60-700C, was qualified. The demonstration of the performances of the new technique under real conditions was made by performing ten full-scale demo tests, each one on an assembly of 100 straight tubes, 1 m long each, for a total of 1000 meters

  10. Solid Oxide Fuel Cell Auxiliary Power Unit

    International Nuclear Information System (INIS)

    Solid Oxide Fuel Cell (SOFC) is an attractive, efficient, clean source of power for transportation, military, and stationary applications. Delphi has pioneered its application as an auxiliary Power Unit (APU) for transportation. Delphi is also interested in marketing this technology for stationary applications. Its key advantages are high efficiency and compatibility with gasoline, natural gas and diesel fuel. It's consistent with mechanizations that support the trend to low emissions. Delphi is committed to working with customers and partners to bring this novel technology to market

  11. Homotopy Perturbation Method with an Auxiliary Term

    Directory of Open Access Journals (Sweden)

    Ji-Huan He

    2012-01-01

    Full Text Available The two most important steps in application of the homotopy perturbation method are to construct a suitable homotopy equation and to choose a suitable initial guess. The homotopy equation should be such constructed that when the homotopy parameter is zero, it can approximately describe the solution property, and the initial solution can be chosen with an unknown parameter, which is determined after one or two iterations. This paper suggests an alternative approach to construction of the homotopy equation with an auxiliary term; Dufing equation is used as an example to illustrate the solution procedure.

  12. Dynamic Response during the Online Compensation of Misalignment Based on Auxiliary Electromagnetic Support

    Institute of Scientific and Technical Information of China (English)

    LI Hui-min; LI Yan; HE Yong

    2008-01-01

    A new support structure,named auxiliary electromagnetic support,is introduced to adjust the position of rotor shaft online.The auxiliary electromagnetic support consists of sliding bearing,iron core,radial spring,pedestal and electroraagnet that could adjust the rotor position.In a rotor system adopting two auxiliary electromagnetic supports,the online compensation of misalignment was achieved without stopping work.Using the proposed auxiliary electromagnetic support,the analytical solution of dynamic response was obtained by analyzing a simulated single-degree-of-freedom(SDOF)system.And the dynamic response of the multi-degrees-of-freedom(MDOF)system in the experiment is acquired using Newmark variable step-size integration method.Further the new design is tested in a symmetrical single-disk rotor-bearing system.With both the theory analysis and the experimental results,some conclusions are obtained about the relationship between the vibration and the system damping which are related to system stability.

  13. The SOL-2/Neto auxiliary protein modulates the function of AMPA-subtype ionotropic glutamate receptors.

    Science.gov (United States)

    Wang, Rui; Mellem, Jerry E; Jensen, Michael; Brockie, Penelope J; Walker, Craig S; Hoerndli, Frédéric J; Hauth, Linda; Madsen, David M; Maricq, Andres V

    2012-09-01

    The neurotransmitter glutamate mediates excitatory synaptic transmission by gating ionotropic glutamate receptors (iGluRs). AMPA receptors (AMPARs), a subtype of iGluR, are strongly implicated in synaptic plasticity, learning, and memory. We previously discovered two classes of AMPAR auxiliary proteins in C. elegans that modify receptor kinetics and thus change synaptic transmission. Here, we have identified another auxiliary protein, SOL-2, a CUB-domain protein that associates with both the related auxiliary subunit SOL-1 and with the GLR-1 AMPAR. In sol-2 mutants, behaviors dependent on glutamatergic transmission are disrupted, GLR-1-mediated currents are diminished, and GLR-1 desensitization and pharmacology are modified. Remarkably, a secreted variant of SOL-1 delivered in trans can rescue sol-1 mutants, and this rescue depends on in cis expression of SOL-2. Finally, we demonstrate that SOL-1 and SOL-2 have an ongoing role in the adult nervous system to control AMPAR-mediated currents.

  14. The auxiliary elliptic-like equation and the exp-function method

    Indian Academy of Sciences (India)

    Hong Li; Jin-Liang Zhang

    2009-06-01

    The auxiliary equation method is very useful for finding the exact solutions of the nonlinear evolution equations. In this paper, a new idea of finding the exact solutions of the nonlinear evolution equations is introduced. The idea is that the exact solutions of the auxiliary elliptic-like equation are derived using exp-function method, and then the exact solutions of the nonlinear evolution equations are derived with the aid of auxiliary elliptic-like equation. As examples, the RKL models, the high-order nonlinear Schrödinger equation, the Hamilton amplitude equation, the generalized Hirota–Satsuma coupled KdV system and the generalized ZK–BBM equation are investigated and the exact solutions are presented using this method.

  15. Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers

    CERN Document Server

    Mullavey, Adam J; Miller, John; Evans, Matthew; Fritschel, Peter; Sigg, Daniel; Waldman, Sam J; Shaddock, Daniel A; McClelland, David E

    2011-01-01

    Residual motion of the arm cavity mirrors is expected to prove one of the principal impediments to systematic lock acquisition in advanced gravitational-wave interferometers. We present a technique which overcomes this problem by employing auxiliary lasers at twice the fundamental measurement frequency to pre-stabilise the arm cavities' lengths. Applying this approach, we reduce the apparent length noise of a 1.3 m long, independently suspended Fabry-Perot cavity to 30 pm rms and successfully transfer longitudinal control of the system from the auxiliary laser to the measurement laser.

  16. Auxiliary pattern for cell-based OPC

    Science.gov (United States)

    Kahng, Andrew B.; Park, Chul-Hong

    2006-10-01

    The runtime of model-based optical proximity correction (OPC) tools has grown unacceptably with each successive technology generation, and has emerged as one of the major bottlenecks for turnaround time (TAT) of IC data preparation and manufacturing. The cell-based OPC approach improves runtime by performing OPC once per cell definition as opposed to once per cell instantiation in the layout. However, cell-based OPC does not comprehend inter-cell optical interactions that affect feature printability in a layout context. In this work, we propose auxiliary pattern-enabled cell-based OPC which can minimize the CD differences between cell-based OPC and model-based OPC. To enable effective insertion of auxiliary pattern (AP) in the design, we also propose a post-placement optimization of a standard cell block with respect to detailed placement. By dynamic programming-based placement perturbation, we achieve 100% AP applicability in designs with placement utilizations of cell-based OPC with AP can match gate edge placement error (EPE) count of model-based OPC within 4%. This is an improvement of 90%, on average, over cell-based OPC without APs. The AP-based OPC approach can reduce OPC runtimes versus model-based OPC by up to 40X in our benchmark designs. We can also achieve reduction of GDSII file size and ORC runtimes due to hierarchy maintenance of cell-based OPC.

  17. Analysis on damage cause of belt eyes for bypass feedwater isolation valves of Daya Bay and Ling'ao NPPs

    International Nuclear Information System (INIS)

    When all of bypass feedwater isolation valves of Daya Bay and Ling'ao NPPs were inspected under disassembled condition, it was found that the belt eyes were damaged in various degrees. The analysis on macro appearance, chemical composition, metallographic, Scanning Electron Microscope and fluid mechanics simulation were carried out on the damaged belt eyes. The results show that the flow rate of belt eye is well above the manufacturer's recommendation so that flow accelerated corrosion and cavitation erosion occur on the belt eyes. According to the damage causes of the belt eyes, corresponding corrective actions are proposed. (authors)

  18. Response of the C-E owners group to the loss-of-feedwater event at the Davis-Besse plant

    International Nuclear Information System (INIS)

    As a result of the Davis-Besse loss of all feedwater event, C-E owners group (CEOG) agreed at its September, 1985 meeting to form a review group for the purpose of evaluating the event with respect to its impact on plants with a C-E nuclear steam supply system (NSSS). Objectives of the review group included review of the Davis-Besse event, determining generic concerns applicable to CEOG plants and development of an action plan to address these concerns. The review documents the inherent design differences between CEOG plants and the Davis-Besse plant. These differences are such that a similar LOF event at a CEOG plant would have a significantly different and improved safety margin relative to that which existed during the Davis-Besse event. Although the impact of this type of event on CEOG plants would be less adverse, the review of the event did identify a number of generic issues for CEOG plants. an action plan was created to address each of the applicable generic issues

  19. Report of the Bulletins and Orders Task Force. Volume II. Appendices

    International Nuclear Information System (INIS)

    Appendices include: Office of Inspection and Enforcement bulletins; NRR status report on feedwater transients in BWR plants; orders on Babcock and Wilcox Company plants; letters lifting orders; letters issuing auxiliary feedwater system requirements; letter to licensees of all operating reactors, dated October 30, 1979 concerning short-term lessons learned requirements; and letters approving guidelines for preparation of small-break LOCA operating procedures

  20. 75 FR 70305 - NextEra Energy Point Beach, LLC, Point Beach Nuclear Plant, Units 1 and 2; Notice of...

    Science.gov (United States)

    2010-11-17

    .../adams.html . From this page, the public can gain entry into ADAMS, which provides text and image files... feedwater isolation valves, modifications to the auxiliary feedwater system, condensate storage tank level... under 10 CFR 2.315(c), must be filed in accordance with the NRC E-Filing rule (72 FR 49139, August...

  1. Next-Generation Evaporative Cooling Systems for the Advanced Extravehicular Mobility Unit Portable Life Support System

    Science.gov (United States)

    Makinen, Janice V.; Anchondo, Ian; Bue, Grant C.; Campbell, Colin; Colunga, Aaron

    2012-01-01

    The development of the Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System (PLSS) is currently underway at NASA Johnson Space Center. The AEMU PLSS features two new evaporative cooling systems, the Reduced Volume Prototype Spacesuit Water Membrane Evaporator (RVP SWME), and the Auxiliary Cooling Loop (ACL). The RVP SWME is the third generation of hollow fiber SWME hardware, and like its predecessors, RVP SWME provides nominal crewmember and electronics cooling by flowing water through porous hollow fibers. Water vapor escapes through the hollow fiber pores, thereby cooling the liquid water that remains inside of the fibers. This cooled water is then recirculated to remove heat from the crewmember and PLSS electronics. Major design improvements, including a 36% reduction in volume, reduced weight, and more flight like back-pressure valve, facilitate the packaging of RVP SWME in the AEMU PLSS envelope. In addition to the RVP SWME, the Auxiliary Cooling Loop (ACL), was developed for contingency crewmember cooling. The ACL is a completely redundant, independent cooling system that consists of a small evaporative cooler--the Mini Membrane Evaporator (Mini-ME), independent pump, independent feed-water assembly and independent Liquid Cooling Garment (LCG). The Mini-ME utilizes the same hollow fiber technology featured in the RVP SWME, but is only 25% of the size of RVP SWME, providing only the necessary crewmember cooling in a contingency situation. The ACL provides a number of benefits when compared with the current EMU PLSS contingency cooling technology; contingency crewmember cooling can be provided for a longer period of time, more contingency situations can be accounted for, no reliance on a Secondary Oxygen Vessel (SOV) for contingency cooling--thereby allowing a SOV reduction in size and pressure, and the ACL can be recharged-allowing the AEMU PLSS to be reused, even after a contingency event. The development of these evaporative cooling

  2. ASCERTAINMENT OF ELECTRIC-SUPPLY SCHEMES RELIABILITY FOR THE ATOMIC POWER PLANT AUXILIARIES

    Directory of Open Access Journals (Sweden)

    A. L. Starzhinskij

    2015-01-01

    Full Text Available The paper completes ascertainment of electrical-supply scheme reliability for the auxiliaries of a nuclear power plant. Thereat the author considers the system behavior during the block normal operation, carrying out current maintenance, and capital repairs in combination with initiating events. The initiating events for reactors include complete blackout, i.e. the loss of outside power supply (normal and reserve; emergency switching one of the working turbogenerators; momentary dumping the normal rating to the level of auxiliaries with seating the cutout valve of one turbo-generator. The combination of any initiating event with the repairing mode in case of one of the system elements failure should not lead to blackout occurrence of more than one system of the reliable power supply. This requirement rests content with the help of the reliable power supply system self-dependence (electrical and functional and the emergency power-supply operational autonomy (diesel generator and accumulator batteries.The reliability indicators of the power supply system for the nuclear power plant auxiliaries are the conditional probabilities of conjoined blackout of one, two, and three sections of the reliable power supply conditional upon an initiating event emerging and the blackout of one, two, and three reliable power-supply sections under the normal operational mode. Furthermore, they also are the blackout periodicity of one and conjointly two, three, and four sections of normal operation under the block normal operational mode. It is established that the blackout of one bus section of normal operation and one section of reliable power-supply system of the auxiliaries that does not lead to complete blackout of the plant auxiliaries may occur once in three years. The probability of simultaneous power failure of two or three normal-operation sections and of two reliable power-supply sections during the power plant service life is unlikely.

  3. Electrical detection of magnetization reversal without auxiliary magnets

    Science.gov (United States)

    Olejník, K.; Novák, V.; Wunderlich, J.; Jungwirth, T.

    2015-05-01

    First-generation magnetic random access memories based on anisotropic magnetoresistance required magnetic fields for both writing and reading. Modern all-electrical read/write memories use instead nonrelativistic spin transport connecting the storing magnetic layer with a reference ferromagnet. Recent studies have focused on electrical manipulation of magnetic moments by relativistic spin torques requiring no reference ferromagnet. Here we report the observation of a counterpart magnetoresistance effect in such a relativistic system which allows us to electrically detect the sign of the magnetization without an auxiliary magnetic field or ferromagnet. We observe the effect in a geometry in which the magnetization of a uniaxial (Ga,Mn)As epilayer is set either parallel or antiparallel to a current-induced nonequilibrium spin polarization of carriers. In our structure, this linear-in-current magnetoresistance reaches 0.2% at current density of 106Acm -2 .

  4. Auxiliary fields in the geometrical relativistic particle dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Amador, A; Bagatella, N; Rojas, E [Departamento de Fisica, Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico); Cordero, R [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N, Edificio 9, 07738 Mexico D.F (Mexico)], E-mail: aramador@gmail.com, E-mail: nbagatella@uv.mx, E-mail: cordero@esfm.ipn.mx, E-mail: efrojas@uv.mx

    2008-03-21

    We describe how to construct the dynamics of relativistic particles, following either timelike or null curves, by means of an auxiliary variables method instead of the standard theory of deformations for curves. There are interesting physical particle models governed by actions that involve higher order derivatives of the embedding functions of the worldline. We point out that the mechanical content of such models can be extracted wisely from a lower order action, which can be performed by implementing in the action a finite number of constraints that involve the geometrical relationship structures inherent to a curve and by using a covariant formalism. We emphasize our approach for null curves. For such systems, the natural time parameter is a pseudo-arclength whose properties resemble those of the standard proper time. We illustrate the formalism by applying it to some models for relativistic particles.

  5. 29 CFR 1917.42 - Miscellaneous auxiliary gear.

    Science.gov (United States)

    2010-07-01

    ...) Bridles for handling flush end or box-type pallets shall be designed to prevent disengagement from the... 29 Labor 7 2010-07-01 2010-07-01 false Miscellaneous auxiliary gear. 1917.42 Section 1917.42 Labor... (CONTINUED) MARINE TERMINALS Cargo Handling Gear and Equipment § 1917.42 Miscellaneous auxiliary gear....

  6. 47 CFR 80.290 - Auxiliary receiving antenna.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not...

  7. Dedicated auxiliary power units for Hybrid Electric Vehicles

    NARCIS (Netherlands)

    Mourad, S.; Weijer, C.J.T. van de

    1998-01-01

    The use of a dedicated auxiliary power unit is essential to utilize the potential that hybrid vehicles offer for efficient and ultra-clean transportation. An example of a hybrid project at the TNO Road-Vehicles Research Institute shows the development and the results of a dedicated auxiliary power u

  8. 基于多参数空气源热泵辅助太阳能热水机组的控制系统%A control system design for solar hot water system with auxiliary air source heat pump based on multiple parameters

    Institute of Scientific and Technical Information of China (English)

    丁鸿昌; 杨前明; 刘其会; 吕帅

    2013-01-01

    The solar hot water system aided by air source heat pump can overcome the drawback of weather influence on single solar hot water system.Based on PLC controller,a control system,which considers multiple parameters such as the sun conditions,water tank temperature,ambient temperature,pipe line pressure,etc.,is designed for a solar hot water system with auxiliary air source heat pump to achieve automatic all-weather hot water supply and save electric energy effectively.%采用了空气源热泵辅助的太阳能热水机组,以解决单一太阳能热水系统受天气条件影响的问题.以PLC控制器为核心,综合考虑光照条件、环境温度、水箱水温、供水压力等多个参数条件,设计了基于多参数的空气源热泵辅助太阳能热水机组的自动控制系统,实现了以太阳能为主热源的热水机组全天候稳定热水供应,有效地节约了能源.

  9. Hydrothermal carbonization of sewage sludge: The effect of feed-water pH on fate and risk of heavy metals in hydrochars.

    Science.gov (United States)

    Zhai, Yunbo; Liu, Xiangmin; Zhu, Yun; Peng, Chuan; Wang, Tengfei; Zhu, Luo; Li, Caiting; Zeng, Guangming

    2016-10-01

    In this study, the effect of feed-water pH (pH=2-12) on fate and risk of heavy metals (HMs) in hydrochars (HCs) was investigated. Hydrothermal carbonization (HTC) of sewage sludge (SS) was carried out with different feed-water pH at 270°C. The research results showed that changing feed-water pH had a positive effect on accumulating Pb, Ni, Cd and Zn in HCs. Chemical forms of Cu and Cr converted from an unstable state to stable in the alkaline environment while in the acidic condition was opposite. The effect of feed-water pH on the chemical forms of HMs was variable but not significant. Risk assessments of Igeo, Er(i), RAC and RI were applied to evaluate the accumulation levels of individual metal, the potential ecological risks, the bio-availabilities and the comprehensive toxicity and sensitivity of HMs, respectively. The lowest pollution level of HMs was obtained at 270°C with pH=11. PMID:27367814

  10. The effects of high hydrazine chemistry on corrosion product transport and feedwater electrochemical potential at Pickering NGS-B, a mixed feedtrain station

    International Nuclear Information System (INIS)

    Pickering NGS-A (Units 1-4) and -B (Units 5-8) is a 8 x 540 MWe CANDU station on Lake Ontario. The in-service date for Unit 7, the subject of this paper, is 1984 October. This unit has been running continuously for 643 days (as of 94.02.01) which extends the previous world record of 533 days for a water power reactor. The materials of construction of the major secondary system components are Admiralty Brass (B111 alloy 443) (Condenser, with a stainless-steel air-removal zone and LP Heaters) and 90/10 Cu/Ni alloy (SB111 alloy C70600) HP Heaters. Each Pickering-B unit has 12 recirculating B and W steam generators, with Monel 400 tubes, carbon steel trefoil broach tube support plates and integral preheaters. Morpholine is injected at the condensate extraction pump discharge and hydrazine is added in the downcomer between the top deaerator spray section and the bottom storage tank. In early 1992, under-deposit pitting of the Monel boiler tubing was identified in Units 5 and 6. Remedial actions taken include steam generator cleaning and a decision to replace copper alloys in the secondary system. One operational action taken was to raise the hydrazine levels on all Pickering-B units with the objective of lowering the feedwater electrochemical potential (ECP) to reduce the risk of further pit initiation and growth. A corrosion product transport (CPT) survey of Unit 7 was performed between 1992 June and 1993 March with extensive use of phase analysis to assess the net benefit of high hydrazine chemistry. Changes in the nature of the corrosion products, especially the ratios of Fe(II):Fe(III) and Cu(II):Cu(I):Cu(O) were monitored to correlate with the reducing conditions produced by the system chemistry. (authors). 4 figs., 3 tabs., 7 refs

  11. Indirect combustion noise of auxiliary power units

    Science.gov (United States)

    Tam, Christopher K. W.; Parrish, Sarah A.; Xu, Jun; Schuster, Bill

    2013-08-01

    Recent advances in noise suppression technology have significantly reduced jet and fan noise from commercial jet engines. This leads many investigators in the aeroacoustics community to suggest that core noise could well be the next aircraft noise barrier. Core noise consists of turbine noise and combustion noise. There is direct combustion noise generated by the combustion processes, and there is indirect combustion noise generated by the passage of combustion hot spots, or entropy waves, through constrictions in an engine. The present work focuses on indirect combustion noise. Indirect combustion noise has now been found in laboratory experiments. The primary objective of this work is to investigate whether indirect combustion noise is also generated in jet and other engines. In a jet engine, there are numerous noise sources. This makes the identification of indirect combustion noise a formidable task. Here, our effort concentrates exclusively on auxiliary power units (APUs). This choice is motivated by the fact that APUs are relatively simple engines with only a few noise sources. It is, therefore, expected that the chance of success is higher. Accordingly, a theoretical model study of the generation of indirect combustion noise in an Auxiliary Power Unit (APU) is carried out. The cross-sectional areas of an APU from the combustor to the turbine exit are scaled off to form an equivalent nozzle. A principal function of a turbine in an APU is to extract mechanical energy from the flow stream through the exertion of a resistive force. Therefore, the turbine is modeled by adding a negative body force to the momentum equation. This model is used to predict the ranges of frequencies over which there is a high probability for indirect combustion noise generation. Experimental spectra of internal pressure fluctuations and far-field noise of an RE220 APU are examined to identify anomalous peaks. These peaks are possible indirection combustion noise. In the case of the

  12. On Partial Opimality by Auxiliary Submodular Problems

    CERN Document Server

    Shekhovtsov, Alexander

    2011-01-01

    In this work, we prove several relations between three different energy minimization techniques. A recently proposed methods for determining a provably optimal partial assignment of variables by Ivan Kovtun (IK), the linear programming relaxation approach (LP) and the popular expansion move algorithm by Yuri Boykov. We propose a novel sufficient condition of optimal partial assignment, which is based on LP relaxation and called LP-autarky. We show that methods of Kovtun, which build auxiliary submodular problems, fulfill this sufficient condition. The following link is thus established: LP relaxation cannot be tightened by IK. For non-submodular problems this is a non-trivial result. In the case of two labels, LP relaxation provides optimal partial assignment, known as persistency, which, as we show, dominates IK. Relating IK with expansion move, we show that the set of fixed points of expansion move with any "truncation" rule for the initial problem and the problem restricted by one-vs-all method of IK would...

  13. National Ignition Facility subsystem design requirements target area auxiliary subsystem SSDR 1.8.6

    International Nuclear Information System (INIS)

    This Subsystem Design Requirement (SSDR) establishes the performance, design, development, and test requirements for the Target Area Auxiliary Subsystems (WBS 1.8.6), which is part of the NIF Target Experimental System (WBS 1.8). This document responds directly to the requirements detailed in NIF Target Experimental System SDR 003 document. Key elements of the Target Area Auxiliary Subsystems include: WBS 1.8.6.1 Local Utility Services; WBS 1.8.6.2 Cable Trays; WBS 1.8.6.3 Personnel, Safety, and Occupational Access; WBS 1.8.6.4 Assembly, Installation, and Maintenance Equipment; WBS 1.8.6.4.1 Target Chamber Service System; WBS 1.8.6.4.2 Target Bay Service Systems

  14. Modelling material effects on flow-accelerated corrosion in primary CANDU coolant and secondary reactor feed-water

    International Nuclear Information System (INIS)

    The effects of chromium content on flow-accelerated corrosion (FAC) of carbon steel have been predicted very well by including a passivating layer, which is a chromium-dependent diffusion barrier at the metal-oxide interface. By adjusting the properties of the chromium-dependent layer, described with a Passivation Parameter (PP), we can predict the FAC of carbon steel of different chromium contents in typical reactor feed-water environments (140oC and neutral or ammoniated chemistry). The model and an appropriate PP are also applied to the environment typical of carbon-steel feeders in the primary coolant of a CANDU reactor (310oC and lithiated chemistry). The model predicts FAC rate very well (with a deviation of 10% or less) in both situations. (author)

  15. Strategic analysis of a manufacturing company and the North American auxiliary power unit market

    OpenAIRE

    Fisher, Craig B.

    2005-01-01

    Power Systems has been the leader in the truck auxiliary power unit business since 2000 and has been making significant advancements in the price of the product as well as its reliability and robustness. Unfortunately the reliability and robustness requirement is increasing further and the profit margin is shrinking to the point that Power Systems needs to undertake a new product development program. The new product offering will result in zero increase in the price to the customer but provid...

  16. Auxiliary Subunit GSG1L Acts to Suppress Calcium-Permeable AMPA Receptor Function

    Science.gov (United States)

    McGee, Thomas P.; Bats, Cécile

    2015-01-01

    synaptic plasticity, and alterations in their expression or regulation are also seen in a number of serious neurological conditions, including stroke, motor neuron disease, and cocaine addiction. Several groups of auxiliary transmembrane proteins have been described that enhance the function and cell-surface expression of AMPARs. We now report that the recently identified auxiliary protein GSG1L decreases weighted mean channel conductance and calcium permeability of CP-AMPARs while increasing polyamine-dependent rectification by diminishing outward current. Our experiments reveal that GSG1L is an auxiliary subunit that can markedly suppress CP-AMPAR function, in both recombinant systems and central neurons. PMID:26658868

  17. Analysis of the OECD/NEA Oskarshamn-2 feedwater transient and stability benchmark with SIMULATE-3K

    International Nuclear Information System (INIS)

    The OECD/NEA recently launched an international benchmark on a combined feedwater transient and stability event that occurred at the Swedish Oskarshamn-2 (O2) nuclear power plant (NPP). The primary benchmark objective is to assess advances in coupled neutronic/thermal-hydraulic codes for simulations of challenging transients including the appearance of unstable power oscillations. The Paul Scherrer Institut (PSI) is participating in this benchmark in order to enlarge the validation basis of its advanced stability analysis methodology currently under development for Swiss BWRs and based on the state-of-the-art SIMULATE-3K (S3K) code. This paper presents the development, optimization and validation of a S3K model for the first phase of the O2 benchmark, namely the analysis of the entire event. With the optimized model, the S3K solution is compared to available benchmark data both for at steady-state and transient conditions. For the latter, the qualitative as well as quantitative behavior of S3K results is compared and discussed in relation to the experimental observations. The modeling aspects found in this context to mostly affect the S3K ability to reproduce the event are also presented. Finally, the S3K model indicates that if the reactor scram had not been introduced, the observed diverging oscillations would reach a maximum amplitude before decaying back into a stable state. However, it was also found that the core could instead have evolved into limit-cycle oscillations if a stabilization of the feedwater flow and temperature had occurred just before the scram signal. (author)

  18. Simulative technology for auxiliary fuel tank separation in a wind tunnel

    Institute of Scientific and Technical Information of China (English)

    Ma Xin; Liu Wei; Chen Ling; Li Xiao; Jia Zhenyuan; Shang Zhiliang

    2016-01-01

    In this paper, we propose a simulative experimental system in wind tunnel conditions for the separation of auxiliary fuel tanks from an aircraft. The experimental system consists of a simulative release mechanism, a scaled model and a pose measuring system. A new release mechanism was designed to ensure stability of the separation. Scaled models of the auxiliary fuel tank were designed and their moment of inertia was adjusted by installing counterweights inside the model. Pose param-eters of the scaled model were measured and calculated by a binocular vision system. Additionally, in order to achieve high brightness and high signal-to-noise ratio of the images in the dark enclosed wind tunnel, a new high-speed image acquisition method based on miniature self-emitting units was pre-sented. Accuracy of the pose measurement system and repeatability of the separation mechanism were verified in the laboratory. Results show that the position precision of the pose measurement system can reach 0.1 mm, the precision of the pitch and yaw angles is less than 0.1? and that of the roll angle can be up to 0.3?. Besides, repeatability errors of models’ velocity and angular velocity controlled by the release mechanism remain small, satisfying the measurement requirements. Finally, experiments for the separation of auxiliary fuel tanks were conducted in the laboratory.

  19. Effect of auxiliary ventilations on diesel particulate matter dispersion inside a dead-end entry

    Institute of Scientific and Technical Information of China (English)

    Zheng Yi; Thiruvengadam Magesh; Lan Hai; Tien C. Jerry

    2015-01-01

    Diesel particulate matter (DPM) is considered carcinogenic after prolonged exposure. This paper used computational fluid dynamics (CFD) method to study the effect of four auxiliary ventilation systems on DPM distribution in a dead-end entry with loading operation. The auxiliary ventilation systems con-sidered include:blower fan and tubing;exhaust fan and tubing, jet fan, and push–pull system. A species transport model with buoyancy effect was used to examine the DPM dispersion pattern with unsteady state analysis. During the 200 s of the loading operation, high DPM levels were identified in the face and dead-end entry regions. This study can be used for mining engineer as guidance to design and setup of local ventilation. It can also be used for selection of DPM control strategies and DPM annual training for underground miners.

  20. Parallel Auxiliary Space AMG Solver for $H(div)$ Problems

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, Tzanio V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-12-18

    We present a family of scalable preconditioners for matrices arising in the discretization of $H(div)$ problems using the lowest order Raviart--Thomas finite elements. Our approach belongs to the class of “auxiliary space''--based methods and requires only the finite element stiffness matrix plus some minimal additional discretization information about the topology and orientation of mesh entities. Also, we provide a detailed algebraic description of the theory, parallel implementation, and different variants of this parallel auxiliary space divergence solver (ADS) and discuss its relations to the Hiptmair--Xu (HX) auxiliary space decomposition of $H(div)$ [SIAM J. Numer. Anal., 45 (2007), pp. 2483--2509] and to the auxiliary space Maxwell solver AMS [J. Comput. Math., 27 (2009), pp. 604--623]. Finally, an extensive set of numerical experiments demonstrates the robustness and scalability of our implementation on large-scale $H(div)$ problems with large jumps in the material coefficients.

  1. A Parallel Auxiliary Grid AMG Method for GPU

    OpenAIRE

    Wang, Lu; Hu, Xiaozhe; Cohen, Jonathan; Xu, Jinchao

    2012-01-01

    In this paper, we develop a new parallel auxiliary grid algebraic multigrid (AMG) method to leverage the power of graphic processing units (GPUs). In the construction of the hierarchical coarse grid, we use a simple and fixed coarsening procedure based on a region quadtree generated from an auxiliary grid. This allows us to explicitly control the sparsity patterns and operator complexities of the AMG solver. This feature provides (nearly) optimal load balancing and predictable communication p...

  2. SEPP-ZVS High Frequency Inverter Incorporating Auxiliary Switch

    Science.gov (United States)

    Ogiwara, Hiroyuki; Itoi, Misao; Nakaoka, Mutsuo

    This paper presents a novel circuit topology to attain ZVS operation of a high frequency inverter over a wide range output power regulation using a PWM control technique by connecting an auxiliary switch to the conventional single ended push-pull (SEPP) ZVS high frequency inverter. A switching current is injected into the main switches via the auxiliary switch only during the short period between its turn-on and off times to supply a current required for its ZVS operation.

  3. Soft switching DC/DC converter using auxiliary circuits

    OpenAIRE

    Jaroslav Dudrik; Vladimír Ruščin

    2008-01-01

    A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.

  4. Alphabet Sizes of Auxiliary Variables in Canonical Inner Bounds

    OpenAIRE

    Jana, Soumya

    2008-01-01

    Alphabet size of auxiliary random variables in our canonical description is derived. Our analysis improves upon estimates known in special cases, and generalizes to an arbitrary multiterminal setup. The salient steps include decomposition of constituent rate polytopes into orthants, translation of a hyperplane till it becomes tangent to the achievable region at an extreme point, and derivation of minimum auxiliary alphabet sizes based on Caratheodory's theorem.

  5. INFLUENCE OF FEEDING ELECTRIC ENERGY QUALITY ON HEATING OF THE AUXILIARY MA-CHINES OF AC ELECTRIC ROLLING STOCK

    Directory of Open Access Journals (Sweden)

    O. YU. Baliichuk

    2014-04-01

    Full Text Available Purpose. The article aims to study the problem of increase the reliability of auxiliary machines for AC electric trains during operation in real conditions. Methodology. The peculiarity of system construction of auxiliary machines for AC electric rolling stock is the use of asynchronous motors for general industrial purpose. An engineering method of influence determination on the feeding voltage asymmetry and its deviation from the nominal value on heating of auxiliary machines insulation was proposed. Findings. It is found out that in case when the auxiliary machines of AC electric trains work under asymmetry factor of the voltage 10% or more and feeding voltage deviation from the nominal order 0.6 relative unit then it is possible the overheat of their isolation, even if it has class H. Originality. For the first time the issue of the total insulation heating under such boundary parameters combinations of energy quality, when each of them contributes to the heating insulation increase as compared to the nominal regime of the "rotating phase splitter−auxiliary machinery" system was illuminated. Practical value. Conducted research allow us to establish the boundary parameter values of feeding energy quality (asymmetry factor, feeding voltage deviations from the nominal value, at which additional isolation overheating of this class under the effect of specified factors will not exceed the agreed value.

  6. Design and Development of Civil Aircraft Flight Performance Auxiliary Calculation System%民用飞机的飞机性能辅助计算系统设计与开发

    Institute of Scientific and Technical Information of China (English)

    褚双磊; 董奇; 刘子昂; 温瑞英

    2016-01-01

    The performance engineer's daily work in the airline is that making the low-speed performance analysis and route operation evaluation by the software performance corresponding to aircraft model,it has a large amount of daily performance calculation. The research is oriented by pre-flight performance assis-tant calculation of performance engineer, the aircraft performance auxiliary calculation software was de-signed and developed. First it established basic performance database of civil aircraft,including aerody-namic data and engine thrust data,the programming language was used in order to complete the primary basic performance calculation, senior professional performance calculation performance curves output of the three main module design,the daily work of the performance engineers achieved quick and simple cal-culation,it laid the data foundation for the follow-up aircraft professional performance calculation,at the same time,it can offer help for the daily performance training of flight dispatcher.%航空公司性能工程师的日常工作就是使用机型对应的飞机性能软件进行低速性能分析和航线评估,日常计算量很大.面向性能工程师的前期飞行性能辅助计算工作,设计并开发了一款飞机性能辅助计算软件,建立机型基础性能数据库,包含气动数据和发动机推力数据,采用编程语言依次完成初级基础性能计算、高级专业性能计算、性能曲线绘制3个主要模块设计、实现性能工程师日常工作的快捷和简便性计算,为后续专业飞机性能计算打下数据基础,同时也可以为飞行签派员的日常性能训练工作提供帮助.

  7. A PPS Sampling Scheme Using Harmonic Mean of An Auxiliary Variable

    OpenAIRE

    L.N. Sahoo; Dalabehera, M.; A.K. Mangaraj

    2012-01-01

    We consider a probability proportional to size sampling scheme by using harmonic mean of an auxiliary variable, when the correlation between study variable and auxiliary variable is highly negative. This is achieved by considering inverse transformation of the auxiliary variable and then utilizing the transformed auxiliary variable values at the design stage of the survey operation in selecting a sample.

  8. 30 CFR 57.8534 - Shutdown or failure of auxiliary fans.

    Science.gov (United States)

    2010-07-01

    ... auxiliary fan failure due to malfunction, accident, power failure, or other such unplanned or unscheduled... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shutdown or failure of auxiliary fans. 57.8534... Ventilation Underground Only § 57.8534 Shutdown or failure of auxiliary fans. (a) Auxiliary fans installed...

  9. VGB guideline for boiler feedwater, boiler water and steam of steam-raising units with a permissible working gauge pressure above 68 bar. VGB-Richtlinie fuer Kesselspeisewasser, Kesselwasser und Dampf von Dampferzeugern ueber 68 bar zulaessigem Betriebsueberdruck

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    The guideline deals with operation with salt-free feed water which is to be regarded as the normal case. The combined feedwater conditioning with NH{sub 4} and O{sub 2}, which has found widespread use in practice, was included. Apart from the guidance values, normal operating values for feedwater and steam are given, as are the theoretical relationships, particularly regarding the formation of a protective layer and the method of chemical conditioning processes is explained. (DG).

  10. AMPA Receptors Commandeer an Ancient Cargo Exporter for Use as an Auxiliary Subunit for Signaling

    OpenAIRE

    Nadine Harmel; Barbara Cokic; Gerd Zolles; Henrike Berkefeld; Veronika Mauric; Bernd Fakler; Valentin Stein; Nikolaj Klöcker

    2012-01-01

    Fast excitatory neurotransmission in the mammalian central nervous system is mainly mediated by ionotropic glutamate receptors of the AMPA subtype (AMPARs). AMPARs are protein complexes of the pore-lining alpha-subunits GluA1-4 and auxiliary beta-subunits modulating their trafficking and gating. By a proteomic approach, two homologues of the cargo exporter cornichon, CNIH-2 and CNIH-3, have recently been identified as constituents of native AMPARs in mammalian brain. In heterologous reconstit...

  11. Dynamic behavior of a magnetic bearing supported jet engine rotor with auxiliary bearings

    Science.gov (United States)

    Flowers, George T.; Xie, Huajun; Sinha, S. C.

    1995-01-01

    This paper presents a study of the dynamic behavior of a rotor system supported by auxiliary bearings. The steady-state behavior of a simulation model based upon a production jet engine is explored over a wide range of operating conditions for varying rotor imbalance, support stiffness, and damping. Interesting dynamical phenomena, such as chaos, subharmonic responses, and double-valued responses, are presented and discussed.

  12. VLTI First Fringes with Two Auxiliary Telescopes at Paranal

    Science.gov (United States)

    2005-03-01

    [Preview - JPEG: 537 x 400 pix - 31k] [Normal - JPEG: 1074 x 800 pix - 555k] [HiRes - JPEG: 3000 x 2235 pix - 6.0M] ESO PR Photo 07d/05 ESO PR Photo 07d/05 [Preview - JPEG: 400 x 550 pix - 60k] [Normal - JPEG: 800 x 1099 pix - 946k] [HiRes - JPEG: 2414 x 3316 pix - 11.0M] Captions: ESO PR Photo 07b/05 shows VLTI Auxiliary Telescopes 1 and 2 (AT1 and AT2) in the early evening light, with the spherical domes opened and ready for observations. In ESO PR Photo 07c/05, the same scene is repeated later in the evening, with three of the large telescope enclosures in the background. This photo and ESO PR Photo 07c/05 which is a time-exposure with AT1 and AT2 under the beautiful night sky with the southern Milky Way band were obtained by ESO staff member Frédéric Gomté. However, most of the time the large telescopes are used for other research purposes. They are therefore only available for interferometric observations during a limited number of nights every year. Thus, in order to exploit the VLTI each night and to achieve the full potential of this unique setup, some other (smaller), dedicated telescopes were included into the overall VLT concept. These telescopes, known as the VLTI Auxiliary Telescopes (ATs), are mounted on tracks and can be placed at precisely defined "parking" observing positions on the observatory platform. From these positions, their light beams are fed into the same common focal point via a complex system of reflecting mirrors mounted in an underground system of tunnels. The Auxiliary Telescopes are real technological jewels. They are placed in ultra-compact enclosures, complete with all necessary electronics, an air conditioning system and cooling liquid for thermal control, compressed air for enclosure seals, a hydraulic plant for opening the dome shells, etc. Each AT is also fitted with a transporter that lifts the telescope and relocates it from one station to another. It moves around with its own housing on the top of Paranal, almost like a snail

  13. Ultrasonic meters in the feedwater flow to recover thermal power in the reactor of nuclear power plant of Laguna Verde U1 and U2; Medidores ultrasonicos en el flujo de agua de alimentacion para recuperar potencia termica en el reactor de la Central Nuclear Laguna Verde U1 and U2

    Energy Technology Data Exchange (ETDEWEB)

    Tijerina S, F. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)]. e-mail: francisco.tijerina@cfe.gob.mx

    2008-07-01

    The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)

  14. IEC 61850. Integrated supervision of auxiliary power equipment; IEC 61850. Prozess und Eigenbedarf wachsen zusammen

    Energy Technology Data Exchange (ETDEWEB)

    Ostertag, Robert; Jung, Matthias [Siemens AG, Erlangen (Germany)

    2009-07-01

    It is state of technology today: Having process control and auxiliary power control integrated in one DCS. The integration is based on the international standard IEC 61850 which allows standardization of electrical structures from the process interface up to the DCS level. Modern control systems are designed to realize a system structure according to IEC 61850. A wide range of systems is available from systems with interfaces to realize a standardized data exchange up to systems with a complete integration of the standard IEC 61850. (orig.)

  15. Green Propulsion Auxiliary Power Unit Demonstration at MSFC

    Science.gov (United States)

    Robinson, Joel W.

    2014-01-01

    In 2012, the National Aeronautics & Space Administration (NASA) Space Technology Mission Directorate (STMD) began the process of building an integrated technology roadmap, including both technology pull and technology push strategies. Technology Area 1 (TA-01)1 for Launch Propulsion Systems is one of fourteen TAs that provide recommendations for the overall technology investment strategy and prioritization of NASA's space technology activities. Identified within TA-01 was the need for a green propulsion auxiliary power unit (APU) for hydraulic power by 2015. Engineers led by the author at the Marshall Space Flight Center (MSFC) have been evaluating green propellant alternatives and have begun the development of an APU test bed to demonstrate the feasibility of use. NASA has residual APU assets remaining from the retired Space Shuttle Program. Likewise, the F-16 Falcon fighter jet also uses an Emergency Power Unit (EPU) that has similar characteristics to the NASA hardware. Both EPU and APU components have been acquired for testing at MSFC. This paper will summarize the status of the testing efforts of green propellant from the Air Force Research Laboratory (AFRL) propellant AFM315E based on hydroxyl ammonium nitrate (HAN) with these test assets.

  16. The chemistry and properties of organic boiler feedwater additives based on film-forming amines and their use in steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Hater, Wolfgang; Russchuetzky, Niels [BK Giulini GmbH, Duesseldorf (Germany); Olivet, David [BK Giulini, Barcelona (Spain)

    2009-02-15

    Film-forming amines have been successfully used for a number of decades to treat boiler feedwater, especially in industrial power plants. The results of recent studies of their properties and the results of operational trials should close the existing gaps in our knowledge of film-forming amines, so that this technology can be incorporated into the appropriate guidelines for the treatment of steam generators. (orig.)

  17. Feedwater production from river water with ion exchange and reverse osmosis. 10 years operation experience; Kesselspeisewasser-Erzeugung aus Flusswasser durch Ionenaustausch und Umkehrosmose. 10 Jahre Betriebserfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Wasel-Nielen, J.; Kluge, H. [InfraServ GmbH und Co. Hoechst KG, Frankfurt am Main (Germany)

    2000-07-01

    Since november 1988 the InfaServ Hoechst KG in Frankfurt am Main processes river water to be used as desalinated feedwater for high pressure steam boilers. Main purposes for the use of reverse osmosis were the reduction of waste water for regeneration and separation of organics contributing to boiler corrosion. Development of a new low pressure membrane reduced the energy demand. Biofouling proofed to be a main problem. Performance and cost are shown.

  18. The use of the vinegar as a chemical auxiliary in Endodontics: a literature review

    Directory of Open Access Journals (Sweden)

    Luis Eduardo Duarte IRALA

    2009-06-01

    Full Text Available Introduction: During the root canal instrumentation with the use of files, there is the formation of a layer called “smear layer”, which may hide among other elements microorganisms capable of perpetuating an endodontic infection, what can lead to endodontic treatment failure. Objective: To present a literature review of apple vinegar and its chemical properties as an auxiliary alternative substance in the permeability in dentin. Literature review: In the attempt to remove the smear layer, auxiliary substances that allow a better action of instruments are used, which also permit the permeability of the system of canals and the removal of organic remains and possible contaminants. Conclusion: The results had indicated that the use of the apple vinegar can be a viable alternative to assist chemistry in Endodontics.

  19. Accuracy of marker-assisted selection with auxiliary traits

    Indian Academy of Sciences (India)

    P Narain

    2003-09-01

    Genetic information on molecular markers is increasingly being used in plant and animal improvement programmes particularly as indirect means to improve a metric trait by selection either on an individual basis or on the basis of an index incorporating such information. This paper examines the utility of an index of selection that not only combines phenotypic and molecular information on the trait under improvement but also combines similar information on one or more auxiliary traits. The accuracy of such a selection procedure has been theoretically studied for sufficiently large populations so that the effects of detected quantitative trait loci can be perfectly estimated. The theory is illustrated numerically by considering one auxiliary trait. It is shown that the use of an auxiliary trait improves the selection accuracy; and, hence, the relative efficiency of index selection compared to individual selection which is based on the same intensity of selection. This is particularly so for higher magnitudes of residual genetic correlation and environmental correlation having opposite signs, lower values of the proportion of genetic variation in the main trait associated with the markers, negligible proportion of genetic variation in the auxiliary trait associated with the markers, and lower values of the heritability of the main trait but higher values of the heritability of the auxiliary trait.

  20. Stochastic gradient algorithm for a dual-rate Box-Jenkins model based on auxiliary model and FIR model

    Institute of Scientific and Technical Information of China (English)

    Jing CHEN; Rui-feng DING

    2014-01-01

    Based on the work in Ding and Ding (2008), we develop a modifi ed stochastic gradient (SG) parameter estimation algorithm for a dual-rate Box-Jenkins model by using an auxiliary model. We simplify the complex dual-rate Box-Jenkins model to two fi nite impulse response (FIR) models, present an auxiliary model to estimate the missing outputs and the unknown noise variables, and compute all the unknown parameters of the system with colored noises. Simulation results indicate that the proposed method is effective.

  1. Feed and Bleed Operation Analysis during Total Loss of Feedwater Accident for Supporting the PSA of APR+

    International Nuclear Information System (INIS)

    For estimating the safety of APR+ design, the probabilistic safety assessment (PSA) is performed. This paper discusses the minimum success criteria for successful feed and bleed procedure verified and decided when the secondary cooling is failed during Total loss of feedwater (TLOFW) accident. For verifying whether the equipment conditions proposed is enough to manage the transient event without core damage, the analysis is performed by RELAP5/MOD 3.3 code. During TLOFW event, the operator's action time is allowed for 80 minutes and the uncovered core could maintain the stable state for a long time, about a half or one hour by the positive effects given by the fast coolant circulation by RCP pump operation. In simulations considering test scenarios, the minimum required equipment for successful F and B managing during TLOFW without LOOP is verified that it is that F and B procedure could be performed successfully as if the operator would open at least one out of four POSRV within 80 minutes after secondary cooling failure for the RCS depressurization. These analysis results can be used for contribute more realistic and accurate performance of a APR+ PSA

  2. A new approach on auxiliary vehicle assignment in capacitated location routing problem

    Science.gov (United States)

    Bashiri, Mahdi; Rasoulinejad, Zeinab; Fallahzade, Ehsan

    2016-03-01

    The location routing problem (LRP) considers locating depots and vehicle routing decisions simultaneously. In classic LRP the number of customers in each route depends on the capacity of the vehicle. In this paper a capacitated LRP model with auxiliary vehicle assignment is presented in which the length of each route is not restricted by main vehicle capacity. Two kinds of vehicles are considered: main vehicles with higher capacity and fixed cost and auxiliary vehicles with lower capacity and fixed cost. The auxiliary vehicles can be added to the transportation system as an alternative strategy to cover the capacity limitations and they are just used to transfer goods from depots to vehicles and cannot serve the customers by themselves. To show the applicability of the proposed model, some numerical examples derived from the well-known instances are used. Moreover the model has been solved by some meta-heuristics for large sized instances. The results show the efficiency of the proposed model and the solution approach, considering the classic model and the exact solution approach, respectively.

  3. Auxiliary en-bloc liver-small bowel transplantation with partial pancreas preservation in pigs

    Institute of Scientific and Technical Information of China (English)

    Zhen-Yu Yin; Xiao-Dong Ni; Feng Jiang; Ning Li; You-Sheng Li; Xiao-Ming Wang; Jie-Shou Li

    2004-01-01

    AIM: The aim of this study was to describe an auxiliary combined liver-small bowel transplantation model with the preservation of duodenum, head of pancreas and hepatic biliary system in pigs. The technique, feasibility, security and immunosuppression were commented.METHODS: Forty outbred long-white pigs were randomized into two groups, and the auxiliary composite liver/small bowel allotransplantations were undertaken in 10 long-white pigs in each group with the recipient liver preserved.Group A was not treated with immunosuppressive drugs while group B was treated with cyclosporine A and methylprednisolone after operation. The hemodynamic changes and amylase of body fluid (including blood, urine and abdominal drain) were analyzed.RESULTS: The average survival time of the animals was 10±1.929 d (6 to 25 d) in group A while more than 30 d in group B. The pigs could tolerate the hemodynamic fluctuation during operation and the hemodynamic parameters recovered to normal 2 h after blood reperfusion. The transient high amylase level was decreased to normal one week after operation and autopsy showed no pancreatitis.CONCLUSION: Auxiliary en-bloc liver-small bowel transplantation with partial pancreas preservation is a feasible and safe model with simplified surgical techniques for composite liver/small bowel transplantation. This model may be used as a preclinical training model for clinical transplantation method, clinical liver-small bowel transplantation related complication research, basic research including immunosuppressive treatment, organ preservation, acute rejection, chronic rejection, immuno-tolerance and xenotransplantation.

  4. Improving Semi-Supervised Learning with Auxiliary Deep Generative Models

    DEFF Research Database (Denmark)

    Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae;

    Deep generative models based upon continuous variational distributions parameterized by deep networks give state-of-the-art performance. In this paper we propose a framework for extending the latent representation with extra auxiliary variables in order to make the variational distribution more...... expressive for semi-supervised learning. By utilizing the stochasticity of the auxiliary variable we demonstrate how to train discriminative classifiers resulting in state-of-the-art performance within semi-supervised learning exemplified by an 0.96% error on MNIST using 100 labeled data points. Furthermore...

  5. Auxiliary tensor fields for Sp(2,R) self-duality

    CERN Document Server

    Ivanov, Evgeny A; Zupnik, Boris M

    2014-01-01

    The coset Sp(2,R)/U(1) is parametrized by two real scalar fields. We generalize the formalism of auxiliary tensor (bispinor) fields in U(1) self-dual nonlinear models of abelian gauge fields to the case of Sp(2,R) self-duality. In this new formulation, Sp(2,R) duality of the nonlinear scalar-gauge equations of motion is equivalent to an Sp(2,R) invariance of the auxiliary interaction. We derive this result in two different ways, aiming at its further application to supersymmetric theories. We also consider an extension to interactions with higher derivatives.

  6. Analysis and Measurement of NOx Emissions in Port Auxiliary Vessels

    Directory of Open Access Journals (Sweden)

    German de Melo Rodriguez

    2013-09-01

    Full Text Available This paper is made NOx pollution emitted by port auxiliary vessels, specifically by harbour tugs, due to its unique operating characteristics of operation, require a large propulsion power changes discontinuously, also possess some peculiar technical characteristics, large tonnage and high propulsive power, that differentiate them from other auxiliary vessels of the port. Taking into account all the above features, there are no studies of the NOx emission engines caused by different working regimes of power because engine manufacturers have not measured these emissions across the range of operating power, but usually we only report the pollution produced by its engines to a maximum continuous power.

  7. PARALLEL AUXILIARY SPACE AMG FOR H(curl) PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Tzanio V. Kolev; Panayot S. Vassilevski

    2009-01-01

    In this paper we review a number of auxiliary space based preconditioners for the second order definite and semi-definite Maxwell problems discretized with the lowest order Nedelec finite elements. We discuss the parallel implementation of the most promising of these methods, the ones derived from the recent Hiptmair-Xu (HX) auxiliary space decomposition [Hiptmair and Xu, SIAM J. Numer. Anal., 45 (2007), pp. 2483-2509]. An extensive set of numerical experiments demonstrate the scalability of our implementation on large-scale H(curl) problems.

  8. Sampling designs dependent on sample parameters of auxiliary variables

    CERN Document Server

    Wywiał, Janusz L

    2015-01-01

    The book offers a valuable resource for students and statisticians whose work involves survey sampling. An estimation of the population parameters in finite and fixed populations assisted by auxiliary variables is considered. New sampling designs dependent on moments or quantiles of auxiliary variables are presented on the background of the classical methods. Accuracies of the estimators based on original sampling design are compared with classical estimation procedures. Specific conditional sampling designs are applied to problems of small area estimation as well as to estimation of quantiles of variables under study. .

  9. TMI-2 auxiliary building elevator shaft and pit decontamination

    International Nuclear Information System (INIS)

    Decontamination of the elevator pit and shaft in the auxiliary building at Three Mile Island Unit 2 (TMI-2) was performed to remove high radiation and contamination levels which prevented personnel from utilizing the elevator. The radiation and contamination levels in the TMI-2 auxiliary building elevator shaft have been reduced to the point where plant personnel are again permitted to ride in the elevator without a radiation work permit, with the exception of access to the 281-ft (basement) level. Based on the declassification and expanded use of the elevator, the task goal has been met. The tax expended 16.16 man-rem and 621 man-hours

  10. Vanishing auxiliary variables in PPS sampling - with applications in microscopy

    DEFF Research Database (Denmark)

    Andersen, Ina Trolle; Hahn, Ute; Jensen, Eva B. Vedel

    Recently, non-uniform sampling has been suggested in microscopy to increase efficiency. More precisely, sampling proportional to size (PPS) has been introduced where the probability of sampling a unit in the population is proportional to the value of an auxiliary variable. Unfortunately, vanishing...... auxiliary variables are a common phenomenon in microscopy and, accordingly, part of the population is not accessible, using PPS sampling. We propose a modification of the design, for which an optimal solution can be found, using a model assisted approach. The optimal design has independent interest...

  11. Compact propane fuel processor for auxiliary power unit application

    Science.gov (United States)

    Dokupil, M.; Spitta, C.; Mathiak, J.; Beckhaus, P.; Heinzel, A.

    With focus on mobile applications a fuel cell auxiliary power unit (APU) using liquefied petroleum gas (LPG) is currently being developed at the Centre for Fuel Cell Technology (Zentrum für BrennstoffzellenTechnik, ZBT gGmbH). The system is consisting of an integrated compact and lightweight fuel processor and a low temperature PEM fuel cell for an electric power output of 300 W. This article is presenting the current status of development of the fuel processor which is designed for a nominal hydrogen output of 1 k Wth,H2 within a load range from 50 to 120%. A modular setup was chosen defining a reformer/burner module and a CO-purification module. Based on the performance specifications, thermodynamic simulations, benchmarking and selection of catalysts the modules have been developed and characterised simultaneously and then assembled to the complete fuel processor. Automated operation results in a cold startup time of about 25 min for nominal load and carbon monoxide output concentrations below 50 ppm for steady state and dynamic operation. Also fast transient response of the fuel processor at load changes with low fluctuations of the reformate gas composition have been achieved. Beside the development of the main reactors the transfer of the fuel processor to an autonomous system is of major concern. Hence, concepts for packaging have been developed resulting in a volume of 7 l and a weight of 3 kg. Further a selection of peripheral components has been tested and evaluated regarding to the substitution of the laboratory equipment.

  12. Green Propulsion Auxiliary Power Unit Demonstration at MSFC

    Science.gov (United States)

    Robinson, Joel W.; Beckel, Steve

    2014-01-01

    In 2012, the National Aeronautics & Space Administration (NASA) Space Technology Mission Directorate (STMD) began the process of building an integrated technology roadmap, including both technology pull and technology push strategies. Technology Area 1 (TA-01) for Launch Propulsion Systems is one of fourteen TA's that provide recommendations for the overall technology investment strategy and prioritization of NASA's space technology activities. Identified within TA-01 was the need for a green propulsion auxiliary power unit (APU) for hydraulic power by 2015. Engineers led by the author at the Marshall Space Flight Center (MSFC) have been evaluating green propellant alternatives and have begun the development of an APU testbed to demonstrate the feasibility of use. NASA has residual APU assets remaining from the retired Space Shuttle Program. Likewise, the F-16 Falcon fighter jet also uses an Emergency Power Unit (EPU) that has similar characteristics to the NASA hardware. Both EPU's and APU components have been acquired for testing at MSFC. In concert with this effort, ATK has been developing green propellant technology based on the Swedish Space Corp ECAPS LMP-103S propellant. Propellant blending and test facilities have been established at ATK's Elkton MD facility with the intent to provide suitable propellant blends for application to green APU systems as well as thrusters. This paper will summarize the status of the testing efforts with ATK for use of the green propellant LMP-103S based on ammonium dinitramide and use of the Air Force Research Laboratory (AFRL) propellant AF-M315E based on hydroxyl ammonium nitrate with these test assets.

  13. Space Shuttle Orbiter auxiliary power unit status

    Science.gov (United States)

    Reck, M.; Loken, G.; Horton, J.; Lukens, W.; Scott, W.; Baughman, J.; Bauch, T.

    An overview of the United States Space Shuttle Orbiter APU, which provides power to the Orbiter vehicle hydraulic system, is presented. Three complete APU systems, each with its own separate fuel system, supply power to three dedicated hydraulic systems. These in turn provide power to all Orbiter vehicle critical flight functions including launch, orbit, reentry, and landing. The basic APU logic diagram is presented. The APU includes a hydrazine-powered turbine that drives a hydraulic pump and various accessories through a high-speed gearbox. The APU also features a sophisticated thermal management system designed to ensure safe and reliable operation in the various launch, orbit, reentry, and landing environments.

  14. Solutions of system of P1 equations without use of auxiliary differential equations coupled; Solucoes do sistema de equacoes P1 sem o uso de equacoes diferenciais auxiliares acopladas

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Aquilino Senra; Silva, Fernando Carvalho da; Cardoso, Carlos Eduardo Santos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2000-07-01

    The system of P1 equations is composed by two equations coupled itself one for the neutron flux and other for the current. Usually this system is solved by definitions of two integrals parameters, which are named slowing down densities of the flux and the current. Hence, the system P1 can be change from integral to only two differential equations. However, there are two new differentials equations that may be solved with the initial system. The present work analyzes this procedure and studies a method, which solve the P1 equations directly, without definitions of slowing down densities. (author)

  15. AP1000给水丧失事故定性分析%Qualitative Accident Analysis on Loss of Normal Feedwater for AP1000

    Institute of Scientific and Technical Information of China (English)

    李延凯; 林萌; 侯东; 李美琳; 杨燕华

    2012-01-01

    针对AP1000核电站,基于两流体最佳估算系统程序RELAP5建立热工水力模型,基于Matlab/Simulink软件及工业组态软件建立相关控制系统数学模型,用于对正常给水丧失事故的计算分析.建模数据主要参考AP1000 Design Control Document(AP1000 DCD),由于建模数据不够充分、详尽,模型不够精确,文中事故分析以定性分析为主.计算结果表明:RELAP5具备计算自然循环的能力,计算结果与DCD中正常给水丧失事故结果总体趋势基本一致,非能动余热排出系统(PRHRS)、堆芯补水箱(CMT)系统能够及时、有效地排出堆芯余热和堆芯衰变热,确保堆芯安全.PRHRS余热排出能力对事故发展有明显影响,模型中PRHRS余热排出能力较强,使冷却剂温度更快地降低到较低水平,导致CMT更早投入以及随后反应堆各参数响应的不同.%For the analysis of loss of normal feedwater accident for AP1000, a thermal-hydraulic model was built based on a two-fluid best estimate code, RELAP5. A control system model was built based on Matlab/Simulink code. As the main data for modeling was from AP1000 Design Control Document (AP1000 DCD), which was inadequate and not accurate enough, the accident analysis was qualitative. The calculation results, overall consistent with the same accident in DCD, show that the RELAP5 code has the ability to calculate the natural circulation. PRHRS and CMT are able to remove the core residual heat, decay heat timely and efficiently during the accident to guarantee the safety of the core. In the calculation model, the capability of PRHRS is stronger, which makes the coolant temperature quickly reduced to a lower level, leading to an earlier actuation of CMT, followed by different responses of the plant.

  16. Power consumption of the ASCV and auxiliary equipment

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen; Pedersen, Jørgen Kaas

    1998-01-01

    Operating an ASCV requires power - to cover the losses in the ASCV itself and to run auxiliary equipment. It is necessary to take this power consumption into account when considering the economical aspects of installing an ASCV.Field measurements of this consumption of the ASCV in Rejsby Hede are...

  17. Verb and auxiliary movement in agrammatic Broca's aphasia

    NARCIS (Netherlands)

    Bastiaanse, Y.R.M.; Thompson, C.K.

    2003-01-01

    Verb production in agrammatic Broca's aphasia has repeatedly been shown to be impaired by a number of investigators. Not only is the number of verbs produced often significantly reduced, but verb inflections and auxiliaries are often omitted as well (e.g., Bastiaanse, Jonkers, & Moltmaker-Osinga, 19

  18. 76 FR 22295 - National Poultry Improvement Plan and Auxiliary Provisions

    Science.gov (United States)

    2011-04-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection 9 CFR Part 145 RIN 0579-AD21 National Poultry Improvement Plan and Auxiliary Provisions Correction In rule document 2011-6539 appearing on pages 15791-15798 in the issue...

  19. 29 CFR 1918.62 - Miscellaneous auxiliary gear.

    Science.gov (United States)

    2010-07-01

    ... box-type pallets shall be designed to prevent disengagement from the pallet under load. (5) Pallets... 29 Labor 7 2010-07-01 2010-07-01 false Miscellaneous auxiliary gear. 1918.62 Section 1918.62 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Cargo Handling Gear and Equipment Other Than...

  20. Continuous Market Engineering - Focusing Agent Behavior, Interfaces, and Auxiliary Services

    OpenAIRE

    Kranz, Tobias Theodor

    2015-01-01

    Electronic markets spread out amongst business entities as well as private individuals. Albeit numerous approaches on developing electronic markets exist, a unified approach targeting market development, redesign, and refinement has been lacking. This thesis studies the potential of continuously improving electronic markets. Thereby, the experiments? design focuses on Agent Behavior, Interfaces, and Auxiliary Services and thus unveils the potential of continuously improving electronic markets.

  1. Regulation of Glutamate Receptors by Their Auxiliary Subunits

    OpenAIRE

    Tomita, Susumu

    2010-01-01

    Glutamate receptors are major excitatory receptors in the brain. Recent findings have established auxiliary subunits of glutamate receptors as critical modulators of synaptic transmission, synaptic plasticity and neurological disorder. The elucidation of the molecular rules governing glutamate receptors and subunits will improve our understanding of synapses and of neural-circuit regulation in the brain.

  2. 40 CFR 1033.510 - Auxiliary power units.

    Science.gov (United States)

    2010-07-01

    ... locomotive is equipped with an auxiliary power unit (APU) that operates during an idle shutdown mode, you must account for the APU's emissions rates as specified in this section, unless the APU is part of an... emission rate (g/hr) as specified in § 1033.530. Add the APU emission rate (g/hr) that you determine...

  3. Auxiliary anatomical labels for joint segmentation and atlas registration

    Science.gov (United States)

    Gass, Tobias; Szekely, Gabor; Goksel, Orcun

    2014-03-01

    This paper studies improving joint segmentation and registration by introducing auxiliary labels for anatomy that has similar appearance to the target anatomy while not being part of that target. Such auxiliary labels help avoid false positive labelling of non-target anatomy by resolving ambiguity. A known registration of a segmented atlas can help identify where a target segmentation should lie. Conversely, segmentations of anatomy in two images can help them be better registered. Joint segmentation and registration is then a method that can leverage information from both registration and segmentation to help one another. It has received increasing attention recently in the literature. Often, merely a single organ of interest is labelled in the atlas. In the presense of other anatomical structures with similar appearance, this leads to ambiguity in intensity based segmentation; for example, when segmenting individual bones in CT images where other bones share the same intensity profile. To alleviate this problem, we introduce automatic generation of additional labels in atlas segmentations, by marking similar-appearance non-target anatomy with an auxiliary label. Information from the auxiliary-labeled atlas segmentation is then incorporated by using a novel coherence potential, which penalizes differences between the deformed atlas segmentation and the target segmentation estimate. We validated this on a joint segmentation-registration approach that iteratively alternates between registering an atlas and segmenting the target image to find a final anatomical segmentation. The results show that automatic auxiliary labelling outperforms the same approach using a single label atlasses, for both mandibular bone segmentation in 3D-CT and corpus callosum segmentation in 2D-MRI.

  4. A study on effective system depressurization during a PWR vessel bottom break LOCA with HPI failure and gas inflow prevention. ROSA-V/LSTF test SB-PV-05

    International Nuclear Information System (INIS)

    A small break loss-of-coolant accident (SBLOCA) experiment was conducted at the Large Scale Test Facility (LSTF) of ROSA-V program to study effects of accident management (AM) measures on core cooling, which are important in case of total failure of high pressure injection (HPI) system during an SBLOCA at a pressurized water reactor (PWR). The LSTF is a full-height and 1/48 volume-scaled facility simulating a 4-loop Westinghouse-type PWR (3423 MWt). The experiment, SB-PV-05, simulated a PWR vessel bottom SBLOCA with a rupture of nine instrument tubes, which is equivalent to 0.18% cold leg break. It is clarified that AM actions with steam generator (SG) depressurization to achieve a primary loop cooling rate at -55 K/h and auxiliary feedwater supply for 30 minutes are effective to avoid core uncovery by actuating the low pressure injection (LPI) system. It is also shown through the comparison with the previous experiment of SB-PV-03 that prevention of non-condensable gas inflow from the accumulator injection system (AIS) is very important to actuate the LPI to achieve adequate core cooling. This report presents experiment results of SB-PV-05 in detail and shows the effects of gas inflow prevention on core cooling through the estimation of primary coolant mass and energy balance in the primary system. (author)

  5. Engineering the CernVM-Filesystem as a High Bandwidth Distributed Filesystem for Auxiliary Physics Data

    Science.gov (United States)

    Dykstra, D.; Bockelman, B.; Blomer, J.; Herner, K.; Levshina, T.; Slyz, M.

    2015-12-01

    A common use pattern in the computing models of particle physics experiments is running many distributed applications that read from a shared set of data files. We refer to this data is auxiliary data, to distinguish it from (a) event data from the detector (which tends to be different for every job), and (b) conditions data about the detector (which tends to be the same for each job in a batch of jobs). Relatively speaking, conditions data also tends to be relatively small per job where both event data and auxiliary data are larger per job. Unlike event data, auxiliary data comes from a limited working set of shared files. Since there is spatial locality of the auxiliary data access, the use case appears to be identical to that of the CernVM- Filesystem (CVMFS). However, we show that distributing auxiliary data through CVMFS causes the existing CVMFS infrastructure to perform poorly. We utilize a CVMFS client feature called "alien cache" to cache data on existing local high-bandwidth data servers that were engineered for storing event data. This cache is shared between the worker nodes at a site and replaces caching CVMFS files on both the worker node local disks and on the site's local squids. We have tested this alien cache with the dCache NFSv4.1 interface, Lustre, and the Hadoop Distributed File System (HDFS) FUSE interface, and measured performance. In addition, we use high-bandwidth data servers at central sites to perform the CVMFS Stratum 1 function instead of the low-bandwidth web servers deployed for the CVMFS software distribution function. We have tested this using the dCache HTTP interface. As a result, we have a design for an end-to-end high-bandwidth distributed caching read-only filesystem, using existing client software already widely deployed to grid worker nodes and existing file servers already widely installed at grid sites. Files are published in a central place and are soon available on demand throughout the grid and cached locally on the

  6. Engineering the CernVM-Filesystem as a High Bandwidth Distributed Filesystem for Auxiliary Physics Data

    Energy Technology Data Exchange (ETDEWEB)

    Dykstra, D. [Fermilab; Bockelman, B. [Nebraska U.; Blomer, J. [CERN; Herner, K. [Fermilab; Levshina, T. [Fermilab; Slyz, M. [Fermilab

    2015-12-23

    A common use pattern in the computing models of particle physics experiments is running many distributed applications that read from a shared set of data files. We refer to this data is auxiliary data, to distinguish it from (a) event data from the detector (which tends to be different for every job), and (b) conditions data about the detector (which tends to be the same for each job in a batch of jobs). Relatively speaking, conditions data also tends to be relatively small per job where both event data and auxiliary data are larger per job. Unlike event data, auxiliary data comes from a limited working set of shared files. Since there is spatial locality of the auxiliary data access, the use case appears to be identical to that of the CernVM- Filesystem (CVMFS). However, we show that distributing auxiliary data through CVMFS causes the existing CVMFS infrastructure to perform poorly. We utilize a CVMFS client feature called 'alien cache' to cache data on existing local high-bandwidth data servers that were engineered for storing event data. This cache is shared between the worker nodes at a site and replaces caching CVMFS files on both the worker node local disks and on the site's local squids. We have tested this alien cache with the dCache NFSv4.1 interface, Lustre, and the Hadoop Distributed File System (HDFS) FUSE interface, and measured performance. In addition, we use high-bandwidth data servers at central sites to perform the CVMFS Stratum 1 function instead of the low-bandwidth web servers deployed for the CVMFS software distribution function. We have tested this using the dCache HTTP interface. As a result, we have a design for an end-to-end high-bandwidth distributed caching read-only filesystem, using existing client software already widely deployed to grid worker nodes and existing file servers already widely installed at grid sites. Files are published in a central place and are soon available on demand throughout the grid and cached

  7. 浅谈我国协警组织及其规范化%A Discussion on the Chinese Auxiliary Police Organization and Its Standardization

    Institute of Scientific and Technical Information of China (English)

    王景平

    2015-01-01

    Compared with the wide existence of auxiliary police, the theoretical research of auxiliary police, its organizational construction and legal construction are obviously insufifcient. The aim of auxiliary police is to assist police officers in performing public duties rather than become police officers’ personal assistants. The law should establish the auxiliary police’s main body status and should not position them as the helpers of police ofifcers. According to the realistic state and defects, Chinese auxiliary police organization should regulate the recruitment, establish the tight organization and management system and strengthen legislation so as to make the auxiliary police management institutionalized and standardized.%与协警的广泛存在相比,协警的理论研究、组织建设及法律建设则明显不足。协警是对警察职务的协助行使,而非对在编警察的个人辅助。法律应确定协警的主体地位,不应将其定位为警察的帮工。根据我国协警组织的现实状态与不足,应当规范协警招录形式,构建严密的组织管理体系,加强立法,实现协警组织管理的法制化、规范化。

  8. PARTICULAR AUXILIARY FEATURES OF DIMENSIONAL THEORY

    Directory of Open Access Journals (Sweden)

    Vardanyan Gumedin Surenovich

    2012-10-01

    Full Text Available New approach to selection of the principal measurement units system, different from the one used in the conventional dimensional theory, is proposed in the article. The new approach expands the capacities of dimensional analysis in the resolution of problems of deformable solid mechanics.

  9. PARTICULAR AUXILIARY FEATURES OF DIMENSIONAL THEORY

    OpenAIRE

    Vardanyan Gumedin Surenovich

    2012-01-01

    New approach to selection of the principal measurement units system, different from the one used in the conventional dimensional theory, is proposed in the article. The new approach expands the capacities of dimensional analysis in the resolution of problems of deformable solid mechanics.

  10. Study on Mitigating Capability of AFW System for SBO Accident%辅助给水系统对缓解全厂断电事故能力研究

    Institute of Scientific and Technical Information of China (English)

    张往锁; 曹夏昕; 阎昌琪; 陈薇

    2012-01-01

    以CPR1000核电站为研究对象,采用RELAP5/MOD3.2轻水堆瞬态分析程序,对系统进行合理简化并建模,模拟系统在全厂断电事故下的瞬态响应过程,研究全厂断电事故发生后辅助给水(AFW)的投入对缓解全厂断电事故的能力.计算结果表明:断电事故发生后,主给水丧失导致一回路压力和冷却剂平均温度在断电后6 s达到峰值;辅助给水投入约200 s后,一回路因热阱丧失而引起的温度和压力升高能有效地得到缓解,为交流电源的恢复及余热排出系统的投入赢得了更多的时间.%The transient characteristic of the simplified system for CPR1000 under the station blackout (SBO) accident was simulated by use of RELAP5/MOD3. 2 code, and the capability of mitigating accident results after auxiliary feedwater (AFW) system operating was also analyzed. The calculation results show that; As a result of the loss of the main water supply, the average temperature and the pressure of the primary system reach their maximum in 6 s after SBO accident; the increasing of temperature and pressure caused by the loss of heat sink is effectively mitigated in about 200 s after the input of auxiliary feed water, and this will win more time for the recovery of AC power and the input of residual heat removal system.

  11. 煤矿副斜井无轨胶轮车阻车系统研制与应用%Development of Car-resistance System of Trackless Rubber Vehicle for Auxiliary Slope and Its Application

    Institute of Scientific and Technical Information of China (English)

    李正甲; 刘邹县; 赵宏伟

    2014-01-01

    In coal mines with shallow-buried and nearly-horizontal footrill or slope lift and transportation, most were designed as slope transportation with trackless rubber vehicle. But domestic car-resistance system design and development of trackless rubber vehicle was blank. This design included electric control technology, radio frequency identification technology, pneumatic control technology, car-re-sistance device, etc. By monitoring vehicle speed with radar speed measurement, vehicle-mounted remote-control as backup protection, when vehicle was out of control, electric system acted timely, car-resistance foam unhooked and realized flexible car-resistance. This system could realize vehicle monitoring, location, data and image upload according to users’ need.%在浅埋深、近水平开采的平硐或斜井提升运输煤矿中,大多设计为斜井无轨运输,无轨胶轮车使用比较广泛。但是国内无轨胶轮车防跑车系统的设计与研制属于空白。本设计包括电气控制技术、无线射频技术、气动控制技术、阻车装置等,通过雷达测速监测车辆运行速度,车载遥控器作为后备保护,当车辆失控时电气系统及时动作,阻车泡沫4s内脱钩到位,起到柔性阻车的效果。根据用户需要本系统还可以实现车辆监测、定位、数据、图像上传等功能。

  12. Safety Assessment of Auxiliary Power Unit (APU) System for Civil Aircraft Based on Dynamic Fault Tree Analysis (DFTA)%基于动态故障树分析的民用飞机辅助动力装置系统安全性评估

    Institute of Scientific and Technical Information of China (English)

    王栋

    2014-01-01

    Traditional fault tree analysis method is widely used for system safety assessment in civil aviation indus-try , but dynamic characteristics of systems/subsystems, including operational sequencing interpretation, spare and redundancy expression cannot be represented by traditional fault trees. On the other hand, civil aircraft auxiliary power unit ( APU) often operates as a redundant system and its behavior can be described by using dynamic fault tree appropriately. As a result, the interest of DFTA application is focused on APU system safety assessment. In this paper, two kinds of dynamic gates ( PAND and CSP) were introduced firstly. Their quantitative calculations were presented by applying Markov model. Then two typical cases with auxiliary power unit ( APU) system safety assess-ment were analyzed by traditional fault tree and dynamic fault tree respectively. Finally the comparison between two kinds of Fault Tree Analysis ( FTA ) was provided and the result indicates that Dynamic Fault Tree Analysis ( DFTA) method based on proper application reaches remarkable accuracy ,and the calculation cost is acceptable when second-order approximation of exponential distribution function is applied.%在民用航空工业领域,传统的故障树分析方法广泛运用于系统安全性评估。然而,包含系统/子系统运行的时序阐述以及备份、冗余表达在内的动态特性不能通过传统故障树呈现。另一方面,民用飞机辅助动力装置( APU)经常作为一个冗余系统运作,因而其行为可以通过运用动态故障树进行适当的描述。所以APU的这种特性激发了动态故障树分析在APU系统安全性评估上应用的关注。首先介绍了两种动态门(优先与门和冷备件门),其定量计算通过施用马尔可夫模型来呈现;然后分别通过传统故障树以及动态故障树分析了APU系统安全性评估的两个典型案例;最后进行了两种故障树分析( FTA )的比较,其

  13. Replacement of electrical protection of generation (main generator, main transformer and auxiliary transformers) and new associated monitoring system; Sustitucion de portecciones electricas de generacion (genrador principal, transformador principal y transformadores auxiliares) y nuevo sistema de supervision asociado

    Energy Technology Data Exchange (ETDEWEB)

    Archilla, J.

    2013-07-01

    The replacement of the electrical protection of generation is a technological quantum leap, since moving from an analog system (known by) (all, intuitive and visual) to a digital (integrates the hardware on a single computer, much more powerful and programmable). The keys to overcoming the challenge are know to manage the technological leap, the operational limitations of plant (keep operating the)preferred sources of energy) and make a good design (including a review independent of the configuration of the relays, taking into account the experience (operational available).

  14. A Convergent Method of Auxiliary Sources for Two-Dimensional Impedance Scatterers With Edges

    DEFF Research Database (Denmark)

    Karamehmedovic, Mirza; Breinbjerg, Olav

    2001-01-01

    A modification to the Method of Auxiliary Sources (MAS) is introduced which renders the method operational for two-dimensional impedance scatterers with edges. The modification consists in letting the auxiliary surface converge to the scatterer physical surface for increasing number of auxiliary ...

  15. 14 CFR 33.96 - Engine tests in auxiliary power unit (APU) mode.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine tests in auxiliary power unit (APU... Engine tests in auxiliary power unit (APU) mode. If the engine is designed with a propeller brake which... in operation, and remain stopped during operation of the engine as an auxiliary power unit (“APU...

  16. Environmental impact assessment of the incineration of municipal solid waste with auxiliary coal in China.

    Science.gov (United States)

    Zhao, Yan; Xing, Wei; Lu, Wenjing; Zhang, Xu; Christensen, Thomas H

    2012-10-01

    The environmental impacts of waste incineration with auxiliary coal were investigated using the life-cycle-based software, EASEWASTE, based on the municipal solid waste (MSW) management system in Shuozhou City. In the current system, MSW is collected, transported, and incinerated with 250 kg of coal per ton of waste. Based on observed environmental impacts of incineration, fossil CO(2) and heavy metals were primary contributors to global warming and ecotoxicity in soil, respectively. Compared with incinerators using excess coal, incineration with adequate coal presents significant benefits in mitigating global warming, whereas incineration with a mass of coal can avoid more impacts to acidification, photochemical ozone and nutrient enrichment because of increased electricity substitution and reduced emission from coal power plants. The "Emission standard of air pollutants for thermal power plants (GB13223-2011)" implemented in 2012 introduced stricter policies on controlling SO(2) and NO(x) emissions from coal power plants. Thus, increased use of auxiliary coal during incineration yields fewer avoided impacts on acidification and nutrient enrichment. When two-thirds of ash is source-separated and landfilled, the incineration of rest-waste presents better results on global warming, acidification, nutrient enrichment, and even ecotoxicity in soil. This process is considered a promising solution for MSW management in Shuozhou City. Weighted normalized environmental impacts were assessed based on Chinese political reduction targets. Results indicate that heavy metal and acidic gas emissions should be given more attention in waste incineration. This study provides scientific support for the management of MSW systems dominated by incineration with auxiliary coal in China. PMID:22683228

  17. 核电站给水加热器建模仿真%Modeling and Simulation on Feed-water Heater of Nuclear Power Plant

    Institute of Scientific and Technical Information of China (English)

    冯可新; 彭敏俊; 徐宇翔; 刘新凯

    2014-01-01

    给水加热器是核电站二回路系统的重要设备之一,能否正常运行对于核电站的安全性和热经济性具有重要影响,采用仿真手段研究给水加热器的运行特性,可为给水加热器的设计和运行提供重要的理论依据。本文针对压水堆核电站的给水加热器建立了分布参数仿真模型,在处理两相流体时采用了近分相模型,对实际核电站给水加热器在不同工况下的运行特性进行了仿真分析,并将仿真值与实际电站运行值进行了对比。结果表明,所建仿真模型的精度有明显改进。%The feed-water heater is one of the major equipments in the secondary loop of nuclear power plant (NPP) ,and its behavior has an important influence on the safe and economical operation of NPP . The research on the behavior of feed-water heater by means of modeling and simulation can provide important theoretical basis for its design and operation .In this paper ,the distributed parameter dynamic models of NPP feed-water heater were established ,in which the nearly separated model was used to deal with two-phase flow .By simulating the behavior of actual NPP feed-water heaters under various operating conditions and comparing the differences between the simulation values and the actual values ,the accuracy of the simulation models was proven to be higher than that of existing models .

  18. Generic evaluation of feedwater transients and small break loss-of-coolant accidents in GE-designed operating plants and near-term operating license applications

    International Nuclear Information System (INIS)

    The results are presented of a generic evaluation of feedwater transients, small-break loss-of-coolant accidents (LOCAs), and other TMI-2-related events for General Electric Company (GE)-designed operating plants and near-term operating license applications to confirm or establish the bases for the continued safe operation of the operating plants. The results of this evaluation are presented in this report in the form of a set of findings and recommendations in each of the principal review areas. Additional review of the accident is continuing and further information is being obtained and evaluated. Any new information will be reviewed and modifications will be made as appropriate

  19. 分体式老年人/残疾人智能室内助动系统的设计与实现%Design and implementation of a split intelligent indoor auxiliary system for the aged and handicapped

    Institute of Scientific and Technical Information of China (English)

    任亚楠; 邹伟; 高舒; 叶爱学; 马岩; 原魁

    2012-01-01

    A separable intelligent indoor movement-aided system composed of an intelligent wheelchair and a U-shaped bed was designed and implemented for the aged and handicapped.The system has the functions of posture alteration , wheelchair aiding, and autonomous bed-chair docking.The intelligent wheelchair can alter its posture among sitting, lying and standing smoothly and safely, while it can be docked into the U-shaped bed automatically and reconfigured to a flat stationary bed.The method for design of some key mechanical sizes was derived, and their influences on the wheelchair's force-bearing under different postures was analyzed, which were used to guide the implementation of the wheelchair' s posture-alteration control.For the docking between the wheelchair and the U-shaped bed, an autonomous docking control strategy was presented based on visual servo.First, the U-shaped bed was identified and its relative pose to the wheelchair was localized according to some Euclid features of specific symbol.Then, the line trajectory tracking was performed to make the wheelchair dock into the bed precisely by using vision feedback and dead reckoning simultaneously.The prototype of the movement-aided system was given, and the experiments validated the feasibility and effectiveness of the designing method and the control algorithm.%针对老年人/残疾人长期卧床以及椅床移位护理强度大的问题,采用分体式设计实现了一种具有体位变换、轮椅助动和自主床椅对接功能的智能室内助动系统.对各姿态下轮椅的尺寸设计和受力情况进行了理论计算和分析,据此实现了体位变换控制;对于狭窄空间下轮椅与床体的自动对接,给出了一种基于视觉伺服的自主对接控制算法:首先通过检测特定标志物识别床体,确定轮椅相对于床体坐标系的位姿;然后依据视觉反馈和里程计航迹推演进行直线跟踪,控制轮椅到达床体中心.实验证明了上述系统及其

  20. 基于辅助线滞生法的Auto CAD R12参数化设计系统%Auto CAD R12 Parametric Design System Based on the Detained Auxiliary Line

    Institute of Scientific and Technical Information of China (English)

    郭启全; 周克绳

    1996-01-01

    本文提出了一种在Auto CAD R12环境下,用C语言(基于ADS)开发二维图形参数化设计的新方法辅助线滞生法.解决了辅助线滞生法与ADS具体结合中的技术难题;阐述了实元素悬挂到辅助元素上的新思想,实现了尺寸驱动;为用户众多的Auto CAD R12增加了新功能.基于该方法的Auto CAD R12参数化设计系统(Auto CAD R12 Parametric Design System--APDS)已用于悬挂输送机、管道油阀及半挂自卸车的设计绘图.

  1. Hepatobiliary function scintigraphy (HBFS) in auxiliary partial liver transplantation - results and analysis of animal study

    International Nuclear Information System (INIS)

    After transplantation of an auxiliary liver lobe, hepatobiliary function scintigraphy (HBFS) using 99mTc-diethyl-IDA was performed for evaluation of the double liver system in healthy domestic pigs. Evaluation was performed using the parameters time activity curves, trend scans and count density rates (transplant versus host liver). Compared to the host liver the transplant revealed a complex impairment of the radiopharmaceuticals biokinetics. The results show that postoperative damage of transplants can be assessed early by scintigraphy as a quantitative measure for the individual function of transplant and host liver in the postoperative phase. (orig.)

  2. Contracted auxiliary Gaussian basis integral and derivative evaluation.

    Science.gov (United States)

    Giese, Timothy J; York, Darrin M

    2008-02-14

    The rapid evaluation of two-center Coulomb and overlap integrals between contracted auxiliary solid harmonic Gaussian functions is examined. Integral expressions are derived from the application of Hobson's theorem and Dunlap's product and differentiation rules of the spherical tensor gradient operator. It is shown that inclusion of the primitive normalization constants greatly simplifies the calculation of contracted functions corresponding to a Gaussian multipole expansion of a diffuse charge density. Derivative expressions are presented and it is shown that chain rules are avoided by expressing the derivatives as a linear combination of auxiliary integrals involving no more than five terms. Calculation of integrals and derivatives requires the contraction of a single vector corresponding to the monopolar result and its scalar derivatives. Implementation of the method is discussed and comparison is made with a Cartesian Gaussian-based method. The current method is superior for the evaluation of both integrals and derivatives using either primitive or contracted functions. PMID:18282025

  3. [The design of bionic left ventricular auxiliary pump].

    Science.gov (United States)

    Jin, Henglin; Hu, Xiaobing; Du, Lei

    2015-01-01

    This paper reports a novel design of bionic left ventricular auxiliary pump, and the characteristic is that elastic diaphragm of pump driven by hydraulic, having smooth, reliable blood supply, can prevent blood clots, can use the flow sensor, pressure sensor detection showing the blood pressure and blood volume at the inlet and outlet of the pump. The pump can go with heart rate synchronization or asynchronous auxiliary by the R wave of human body's ECG. The design goal is realization of bionic throb. Through the animal experiment, the blood pressure waveforms are close to expectations, stable flow can stroke according to the set value, which prove that the pump can meet the requirement for heart disease patients for bionic left ventricular assistant.

  4. 新刑事诉讼法专家辅助人制度的立法缺陷及其完善%Defects and pefection of the experts auxiliary system of the new Criminal Procedural Law

    Institute of Scientific and Technical Information of China (English)

    宫雪

    2014-01-01

    Because of the scientific and professional characteristics, the expert opinion has been becoming more and more important in the system of evidence, and gradually replaces the confession. However, the prosecution, the defense and the judges don’t have the expertise. Therefore, it is necessary to engage other people with the expertise to help the parties to solve the problems. The new Criminal Procedural Law was able to confirm that, but it is still flawed and must be urgently improved.%专家辅助人制度在新刑事诉法中的确立无疑将有助于推动鉴定人出庭作证效果的实现,确保鉴定意见的真实性和法官对鉴定意见的正确认定。在此之前,民诉法的有关规定和司法实践的积极探索也为刑事诉讼中专家辅助人制度的完善提供了有效参考。但目前我国有关专家辅助人制度的规定,无论是新刑诉法还是司法运作中依然存在缺陷,包括专家辅助人资格不明确、诉讼地位不确定、权利义务和出庭程序欠缺等。这些都亟需通过立法予以进一步完善,以确保专家辅助人制度能够发挥其应有的作用。

  5. Contracted auxiliary Gaussian basis integral and derivative evaluation

    OpenAIRE

    Giese, Timothy J.; York, Darrin M.

    2008-01-01

    The rapid evaluation of 2-center Coulomb and overlap integrals between contracted auxiliary solid harmonic Gaussian functions is examined. Integral expressions are derived from the application of Hobson’s theorem and Dunlap’s product and differentiation rules of the spherical tensor gradient operator. It is shown that inclusion of the primitive normalization constants greatly simplifies the calculation of contracted functions corresponding to a Gaussian multipole expansion of a diffuse charge...

  6. Mixed Bayesian Networks with Auxiliary Variables for Automatic Speech Recognition

    OpenAIRE

    Stephenson, Todd Andrew; Magimai.-Doss, Mathew; Bourlard, Hervé

    2001-01-01

    Standard hidden Markov models (HMMs), as used in automatic speech recognition (ASR), calculate their emission probabilities by an artificial neural network (ANN) or a Gaussian distribution conditioned on the hidden state variable, considering the emissions independent of any other variable in the model. Recent work showed the benefit of conditioning the emission distributions on a discrete auxiliary variable, which is observed in training and hidden in recognition. Related work has shown the ...

  7. A magnetorheological clutch for efficient automotive auxiliary device actuation

    OpenAIRE

    F. Bucchi; Forte, P; F. Frendo; R. Squarcini

    2013-01-01

    In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design, testing and application of a magnetorheological clutch (MR) is proposed, aimed at disengaging the vacuum pump, which draws in air from the power-brake booster chamber, in order to reduce the device power absorption. Several clutch preliminary studies done to choose the clutch geometry and the magnetic field supply are...

  8. Neoclassical offset toroidal velocity and auxiliary ion heating in tokamaks

    Science.gov (United States)

    Lazzaro, E.

    2016-05-01

    In conditions of ideal axisymmetry, for a magnetized plasma in a generic bounded domain, necessarily toroidal, the uniform absorption of external energy (e.g., RF or any isotropic auxiliary heating) cannot give rise to net forces or torques. Experimental evidence on contemporary tokamaks shows that the near central absorption of RF heating power (ICH and ECH) and current drive in presence of MHD activity drives a bulk plasma rotation in the co- I p direction, opposite to the initial one. Also the appearance of classical or neoclassical tearing modes provides a nonlinear magnetic braking that tends to clamp the rotation profile at the q-rational surfaces. The physical origin of the torque associated with P RF absorption could be due the effects of asymmetry in the equilibrium configuration or in power deposition, but here we point out also an effect of the response of the so-called neoclassical offset velocity to the power dependent heat flow increment. The neoclassical toroidal viscosity due to internal magnetic kink or tearing modes tends to relax the plasma rotation to this asymptotic speed, which in absence of auxiliary heating is of the order of the ion diamagnetic velocity. It can be shown by kinetic and fluid calculations, that the absorption of auxiliary power by ions modifies this offset proportionally to the injected power thereby forcing the plasma rotation in a direction opposite to the initial, to large values. The problem is discussed in the frame of the theoretical models of neoclassical toroidal viscosity.

  9. Bayesian Analysis of Geostatistical Models With an Auxiliary Lattice

    KAUST Repository

    Park, Jincheol

    2012-04-01

    The Gaussian geostatistical model has been widely used for modeling spatial data. However, this model suffers from a severe difficulty in computation: it requires users to invert a large covariance matrix. This is infeasible when the number of observations is large. In this article, we propose an auxiliary lattice-based approach for tackling this difficulty. By introducing an auxiliary lattice to the space of observations and defining a Gaussian Markov random field on the auxiliary lattice, our model completely avoids the requirement of matrix inversion. It is remarkable that the computational complexity of our method is only O(n), where n is the number of observations. Hence, our method can be applied to very large datasets with reasonable computational (CPU) times. The numerical results indicate that our model can approximate Gaussian random fields very well in terms of predictions, even for those with long correlation lengths. For real data examples, our model can generally outperform conventional Gaussian random field models in both prediction errors and CPU times. Supplemental materials for the article are available online. © 2012 American Statistical Association, Institute of Mathematical Statistics, and Interface Foundation of North America.

  10. Effects of C arm X-ray perspective computer auxiliary surgery navigation system on screw fixation in the elderly lumbar vertebrae pedicle%C臂透视计算机辅助导航对老年人腰椎椎弓根螺钉置入术及手术疗效的影响

    Institute of Scientific and Technical Information of China (English)

    张良; 孙常太; 徐宏兵; 张华俦; 王英民

    2012-01-01

    Objective To investigate the influence of C arm X- ray perspective computer auxiliary surgery navigation system on lumbar vertebral pedicle screw fixation in the elderly.Methods 286 patients(aged≥65 years) treated by lumbar spine post decompress and pedicle screw fixation for lumbar vertebral degeneration were divided into navigation (n=153) or non-navigation (n=133) groups.The amount of blood loss,surgery duration and time of beginning to walk after surgery were measured and compared, the improvement grading was determined by Oswestry disability index (ODI) before surgery and at the last follow-up. Results The surgery duration [(27.6+6.3)ain vs.(33.8±9.9)min],the volume of blood loss[(135.7±21.1)ml vs.(165.4±32.1)ml] and the time of beginning to walk after surgery[(134.6± 12.3)h vs.(169.0±23.9)h] were obviously reduced in navigation group as compared with non-navigation group (P < 0.05). The grading improvement rate by ODI[(76.6±±3.7)%vs.(69.8+6.6)%] was higher in navigation group than in non navigation group (P<0.05). Conclusions Using C arm X-ray perspective computer auxiliary surgery navigation system to lumbar pedicle screws fixation is helpful in the elderly for improving clinical efficacy.%目的 探讨C型臂透视计算机辅助手术导航系统对于老年人腰椎椎弓根螺钉置入术的影响. 方法 对286例65岁及以上行腰椎后路减压内固定的腰椎退行性疾病患者分为导航(153例)和未导航(133例)两组,比较两组患者的术中失血量、手术时问和术后下地时间.应用Oswestry功能障碍指数问卷表(ODI)对所有患者的术前和末次随访评分,计算2次评分的ODI评分改善率. 结果 导航组与未导航组相比,椎弓根手术时间[ (27.6±6.3)min、(33.8±9.9)min]和出血量[(135.7±21.1)ml、(165.4±32.1)ml]减少,术后下地时间[(134.6±12.3)h、(169.0=23.9)h]缩短;ODI评分改善率[(76.6±3.7)%、(69.8±6.6)%]提高. 结论 C型臂透视计算机辅助手术导

  11. Verification of the primary system break size grouping as used in the Nuclear Power Plant Krskko (NEK) Individual Plant Examination (IPE)

    International Nuclear Information System (INIS)

    Definition of the small break loss of coolant accident window directly influences probabilistic safety analysis results, since auxiliary feedwater is required as additional system for the successful sequence path. In this report best-estimate thermohydraulic code RELAP5/mod2 has been used to define threshold break size between medium and small break loss of coolant accident according to the NEK IPE definition. Significant thermohydraulic aspects were reasonably well predicted in RELAP5/mod2 calculations. The comparison of RELAP5/mod2 results with comparable MAAP results has shown that this threshold is lower than in the case of NEK IPE MAAP analysis. Since both codes predicted qualitatively comparable plant response for similar initial and boundary conditions, the definition of the threshold in the NEK IPE MAAP calculations is consistent with the mathematical model used in the NEK IPE analysis. The difference in the reactor coolant pump trip criteria at present with the criteria utilized in the NEK PSA level 1 MAAP calculations was investigated, and it was found that the threshold break size could be shifted by the effect of this/such a change. (author)

  12. Dual-Antenna Terrestrial Laser Scanner Georeferencing Using Auxiliary Photogrammetric Observations

    Directory of Open Access Journals (Sweden)

    Benjamin Wilkinson

    2015-09-01

    Full Text Available Terrestrial laser scanning typically requires the use of artificial targets for registration and georeferencing the data. This equipment can be burdensome to transport and set up, representing expense in both time and labor. Environmental factors such as terrain can sometimes make target placement dangerous or impossible, or lead to weak network geometry and therefore degraded product accuracy. The use of additional sensors can help reduce the required number of artificial targets and, in some cases, eliminate the need for them altogether. The research presented here extends methods for direct georeferencing of terrestrial laser scanner data using a dual GNSS antenna apparatus with additional photogrammetric observations from a scanner-mounted camera. Novel combinations of observations and processing methods were tested on data collected at two disparate sites in order to find the best method in terms of processing efficiency and product quality. In addition, a general model for the scanner and auxiliary data is given which can be used for least-squares adjustment and uncertainty estimation in similar systems with varied and diverse configurations. We found that the dual-antenna system resulted in cm-level accuracy practical for many applications and superior to conventional one-antenna systems, and that auxiliary photogrammetric observation significantly increased accuracy of the dual-antenna solution.

  13. Production of high quality distillate to meet a fit-for-purpose boiler feedwater specification

    Energy Technology Data Exchange (ETDEWEB)

    Minnich, K. [Veolia Water Solutions Oil and Gas, Calgary, AB (Canada); Neu, D. [Veolia Water Solutions and Technologies/HPD, Pewaukee, WI (United States); Drone, J.L. [Veolia Water Solutions and Technologies/HPD, Plainfield, IL (United States)

    2009-07-01

    Veolia Water Solutions and Technologies has significant experience managing boiler water chemistry and is the world's largest manufacturer of evaporation systems. The company has conducted extensive testing and analysis for produced water evaporation distillate from multiple facilities. In order to produce boiler feed water, evaporation of produced water is used at several steam assisted gravity drainage (SAGD) facilities. There are no official guidelines for the required quality of evaporator distillate to feed a once through steam generator (OTSG) or high pressure industrial watertube boiler (IWT) that will produce injection steam. This paper presented a basis for a fit-for-purpose specification for IWT boilers as well as data on the performance of a Vapor Washer, which produces high quality distilled water that meets fit-for-purpose specifications even during normal variations in feed conditions. Specifically, the paper discussed boiler water requirements for steam injection IWTs; the quality of distillate from a produced water evaporator; the benefits of vapour washing to maintain distillate quality; and suggested boiler chemistry limits for a fit-for-purpose specification. Oxygen, iron, and copper were discussed as being implicated with corrosion and reaction in boilers. Hardness contaminants such as calcium and magnesium were also presented. Suggested limits for boiler water in the fit-for-purpose specification were also presented for silica, total alkalinity, free OH alkalinity, and total dissolved solids in steam. It was concluded that foaming episodes can occur in produced water evaporators due to normal variations, and the distillate can fail to meet the fit-for-purpose specification during foam upsets. 3 refs., 9 figs.

  14. A new approach for AC loss reduction in HTS transformer using auxiliary windings, case study: 25 kA HTS current injection transformer

    International Nuclear Information System (INIS)

    AC loss is one of the important parameters in HTS (high temperature superconducting) AC devices. Among the HTS AC power devices, the transformer is an essential part in the electrical power system. The AC losses in an HTS tape depend on the magnetic field. One of the techniques usually adopted to mitigate the unwanted magnetic field is using a system of coils that produce a magnetic field opposite to the incident one, reducing the total magnetic field. In this paper adding two auxiliary windings to the HTS transformer to produce this opposite magnetic field is proposed. The proper use of these auxiliary windings could reduce the leakage flux and, therefore, the AC loss. A mathematical model is used to describe the behaviour of a transformer operating with auxiliary windings, based on the theory of electromagnetic coupled circuits. The influence of the auxiliary windings on the leakage field is studied by the finite element method (FEM) and the AC loss of an HTS transformer was calculated. Also, the simulation results show that employing auxiliary windings will improve the HTS transformer efficiency

  15. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders - A Reference Solution for the Numerical Method of Auxiliary Sources

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    To facilitate the validation of the numerical Method of Auxiliary Sources an analytical Method of Auxiliary Sources solution is derived in this paper. The Analytical solution is valid for transverse magnetic, and electric, plane wave scattering by circular impedance Cylinders, and it is derived...

  16. Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power

    Energy Technology Data Exchange (ETDEWEB)

    Vesely, Charles John-Paul [Cummins Power Generation; Fuchs, Benjamin S. [Cummins Power Generation; Booten, Chuck W. [Protonex Technology, LLC

    2010-03-31

    The following report documents the progress of the Cummins Power Generation (CPG) Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power (SOFC APU) development and final testing under the U.S. Department of Energy (DOE) Energy Efficiency and Renewable Energy (EERE) contract DE-FC36-04GO14318. This report overviews and summarizes CPG and partner development leading to successful demonstration of the SOFC APU objectives and significant progress towards SOFC commercialization. Significant SOFC APU Milestones: Demonstrated: Operation meeting SOFC APU requirements on commercial Ultra Low Sulfur Diesel (ULSD) fuel. SOFC systems operating on dry CPOX reformate. Successful start-up and shut-down of SOFC APU system without inert gas purge. Developed: Low cost balance of plant concepts and compatible systems designs. Identified low cost, high volume components for balance of plant systems. Demonstrated efficient SOFC output power conditioning. Demonstrated SOFC control strategies and tuning methods.

  17. Fuel Cell Auxiliary Power Study Volume 1: RASER Task Order 5

    Science.gov (United States)

    Mak, Audie; Meier, John

    2007-01-01

    This study evaluated the feasibility of a hybrid solid oxide fuel cell (SOFC) auxiliary power unit (APU) and the impact in a 90-passenger More-Electric Regional Jet application. The study established realistic hybrid SOFC APU system weight and system efficiencies, and evaluated the impact on the aircraft total weight, fuel burn, and emissions from the main engine and the APU during cruise, landing and take-off (LTO) cycle, and at the gate. Although the SOFC APU may be heavier than the current conventional APU, its weight disadvantage can be offset by fuel savings in the higher SOFC APU system efficiencies against the main engine bleed and extraction during cruise. The higher SOFC APU system efficiency compared to the conventional APU on the ground can also provide considerable fuel saving and emissions reduction, particularly at the gate, but is limited by the fuel cell stack thermal fatigue characteristic.

  18. PEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid Vehicle

    Directory of Open Access Journals (Sweden)

    Tinton Dwi Atmaja

    2012-02-01

    Full Text Available Page HeaderOpen Journal SystemsJournal HelpUser You are logged in as...aulia My Journals My Profile Log Out Log Out as UserNotifications View (27 new ManageJournal Content SearchBrowse By Issue By Author By Title Other JournalsFont SizeMake font size smaller Make font size default Make font size largerInformation For Readers For Authors For LibrariansKeywords CBPNN Displacement FLC LQG/LTR Mixed PMA Ventilation bottom shear stress direct multiple shooting effective fuzzy logic geoelectrical method hourly irregular wave missile trajectory panoramic image predator-prey systems seawater intrusion segmentation structure development pattern terminal bunt manoeuvre Home About User Home Search Current Archives ##Editorial Board##Home > Vol 23, No 1 (2012 > AtmajaPEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid VehicleTinton Dwi Atmaja, Amin AminAbstractone of the present-day implementation of fuel cell is acting as main power source in Fuel Cell Hybrid Vehicle (FCHV. This paper proposes some strategies to optimize the performance of Polymer Electrolyte Membrane Fuel Cell (PEMFC implanted with auxiliary power source to construct a proper FCHV hybridization. The strategies consist of the most updated optimization method determined from three point of view i.e. Energy Storage System (ESS, hybridization topology and control system analysis. The goal of these strategies is to achieve an optimum hybridization with long lifetime, low cost, high efficiency, and hydrogen consumption rate improvement. The energy storage system strategy considers battery, supercapacitor, and high-speed flywheel as the most promising alternative auxiliary power source. The hybridization topology strategy analyzes the using of multiple storage devices injected with electronic components to bear a higher fuel economy and cost saving. The control system strategy employs nonlinear control system to optimize the ripple factor of the voltage and the current

  19. Standard review plan for the review of safety analysis reports for nuclear power plants

    International Nuclear Information System (INIS)

    Revised information is presented concerning the stress analysis of engineered safety systems; control rod drive systems; reactor core isolation coding system; residual heat removal system; emergency core cooling system; station service water system; reactor auxiliary coding water systems; main steam supply system; and condensate and feedwater system

  20. Comment: ``On the computation of molecular auxiliary functions and ”

    Indian Academy of Sciences (India)

    Frank E Harris

    2003-10-01

    Guseinov, Mamedov, Kara and Orbay (Pramana – J. Phys. 56, 691 (2001)) propose methods for evaluating the molecular auxiliary functions () and () for the range 17 ≤ ≤ 60 and 25 ≤ ≤ 60. However, their procedure for () is not new, and that for () is less efficient for their target range than another well-known method. Their approach does have merit for smaller non-zero values of . Two minor errors in table 1 of their paper are also identified.

  1. Fault detection and diagnosis of the deaerator level control system in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Youn; Lee, Yoon Joon [Cheju National Univ., Cheju (Korea, Republic of)

    2004-02-01

    The deaerator of a power plant is one of feedwater heaters in the secondary system, and it is located above the feedwater pumps. The feedwater pumps take the water from the deaerator storage tank, and the Net Positive Suction Head(NPSH) should always be ensured. To secure the sufficient NPSH, the deaerator tank is equipped with the level control system of which level sensors are critical items. And it is necessary to ascertain the sensor state on-line. For this, a model-based Fault Detection and Diagnosis(FDD) is introduced in this study. The dynamic control model is formulated from the relation of input-output flow rates and liquid-level of the deaerator storage tank. Then an adaptive state estimator is designed for the fault detection and diagnosis of sensors. The performance and effectiveness of the proposed FDD scheme are evaluated by applying the operation data of Yonggwang Units 3 and 4.

  2. AMPA receptors commandeer an ancient cargo exporter for use as an auxiliary subunit for signaling.

    Directory of Open Access Journals (Sweden)

    Nadine Harmel

    Full Text Available Fast excitatory neurotransmission in the mammalian central nervous system is mainly mediated by ionotropic glutamate receptors of the AMPA subtype (AMPARs. AMPARs are protein complexes of the pore-lining α-subunits GluA1-4 and auxiliary β-subunits modulating their trafficking and gating. By a proteomic approach, two homologues of the cargo exporter cornichon, CNIH-2 and CNIH-3, have recently been identified as constituents of native AMPARs in mammalian brain. In heterologous reconstitution experiments, CNIH-2 promotes surface expression of GluAs and modulates their biophysical properties. However, its relevance in native AMPAR physiology remains controversial. Here, we have studied the role of CNIH-2 in GluA processing both in heterologous cells and primary rat neurons. Our data demonstrate that CNIH-2 serves an evolutionarily conserved role as a cargo exporter from the endoplasmic reticulum (ER. CNIH-2 cycles continuously between ER and Golgi complex to pick up cargo protein in the ER and then to mediate its preferential export in a coat protein complex (COP II dependent manner. Interaction with GluA subunits breaks with this ancestral role of CNIH-2 confined to the early secretory pathway. While still taking advantage of being exported preferentially from the ER, GluAs recruit CNIH-2 to the cell surface. Thus, mammalian AMPARs commandeer CNIH-2 for use as a bona fide auxiliary subunit that is able to modify receptor signaling.

  3. Sub compartment pressurization analysis for auxiliary building of APR1400DC

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Moon Oh; Lee, Hee Do [Atomic Creative Technology, Daejeon (Korea, Republic of)

    2012-10-15

    Generally, the sub compartment of PWR means a fully or partially enclosed volume that could house high-energy piping systems or restrict the flow of fluid in the event of a postulated pipe rupture. To meet the requirements of General Design Criteria (GDC) 4 and 50, Standard Review Plan (SRP) 6.2.1.2 states that the sub compartments shall be designed with sufficient margin to prevent the fracture of structure due to pressure differential across the walls of the sub- compartment and specifies the criteria related to the design and functional sub compartment nodalization schemes, vent flow path and vent flow behavior. Therefore the sub compartments structures within the containment and auxiliary building are designed to withstand the transient differential pressures loads, jet impingement forces, and pipe whip forces occurring due to a postulated pipe break. In this paper, the analyses of pressure transients after a postulated pipe rupture in sub compartments of APR1400DC auxiliary building is performed and the calculated peak differential pressures during the piping break transients for each sub compartment are less than structural design differential pressures.

  4. Phonetic physical feature formula for identification of radiation auxiliary workers and security applications

    International Nuclear Information System (INIS)

    This report gives a review of human physical features with the aim of evolving a simple and practical formula which can be used to identify radiation auxiliary workers even if they do not reveal their radiation work history either due to ignorance or intentionally. To have the formula short, the phonetic number system of radix 128 has been employed. The formula finally arrived at consists of three phonetic digits representing 17 features and age in blocks of 8 years. There are four main advantages of this formula. The first is binary division which has more surety and better accuracy. The second is expert redundancy, that is expert examination is not required. Third is very large number of categories (128K=131072). And the fourth is nearly equal probabilities of all categories which make the number of people in each category very few and that simplifies the search. Hence by the scan of a few records, it is easily possible to ascertain whether a person is a new entrant or an old timer. Its application ensures better monitoring of the radiation exposure of auxiliary workers. This formula can also be used by police department and investigating agencies to classify the records of suspected persons for the ease of their identification when they give misleading information

  5. Thermal-hydraulic Analysis of SGTR for Supporting PSA in APR+

    International Nuclear Information System (INIS)

    The Advanced Power Reactor Plus (APR+) is being developed in Korea. To enhance the safety of the APR+, a passive auxiliary feedwater system (PAFS) has been adopted in the APR+. The PAFS completely replaces the conventional active auxiliary feedwater system (AFWS). It is operated by a natural driving force mechanism when demanding auxiliary feedwater. It could maintain the system function of cooling the primary side and remove the decay heat while operated PAFS. For estimating the safety of APR+ design, the probabilistic safety assessment (PSA) of APR+ is performed. As the PAFS replaces the conventional AFWS, it is required to verify the cooling capacity of PAFS for the accurate evaluation. For this reason, this paper discusses the cooling performance of the PAFS while transient accidents

  6. Combined small bowel and reduced auxiliary liver transplantation: case report

    Institute of Scientific and Technical Information of China (English)

    Wei-Jie Zhang; Dun-Gui Liu; Qi-Fa Ye; Bo Sha; Fan-Jun Zhen; Hui Guo; Sui-Sheng Xia

    2002-01-01

    AIM: To present a case of combined small bowel andreduced auxiliary liver transplantation.METHODS: A 55-year-old patient with short bowelsyndrome and TPN-related liver dysfunction received smallbowel transplantation combined with a reduced auxiliaryliver graft. A liver was added to restore the patient′s liverfunction and to protect the intestinal allograft from rejection.His own liver was not removed.RESULTS: Without donor pretreatment and by conventionalimmunosuppresive therapy following transplantation, thepatient experienced had only one episode of mild intestinalrejection, which was easily reversed by treatment withMethylprednisolone. No liver rejection occurred.Unfortunately, the patient died of heart and lung failure30d after transplantation, despite successful graftreplacement. Histopathologic examination of specimens afterdeath demonstrated normal structure in both intestinal andliver grafts.CONCLUSION: The auxiliary liver graft might play a role inpreventing intestinal allograft rejection. However, theobservation period in this case is short. Further study isneeded to determine the risks, effect on the protecting thesmall-bowel from rejection, and feasibility of generalapplication of this procedure.

  7. A Study of the Disturbance in Steam Power Unit Caused by Solar Auxiliary Heating System%太阳能辅助加热系统对蒸汽动力机组运行性能的扰动研究

    Institute of Scientific and Technical Information of China (English)

    安连锁; 徐玫; 陈海平; 冯蕾; 张衡

    2015-01-01

    It is common that variable conditions are considered in the process of solar-assisted coal-fired power system designing. Small disturbance theory tells us that when no obvious water distribution happens complex variable conditions calculation can be saved and the results which meet required precision can be achieved as well. A quantitative analysis was conducted for the impact of the solar auxiliary heating system on the thermal system. The results show that within a small range the impact caused by the solar auxiliary heating system can be regarded as a small disturbance, while in the usual range(30% to 100%) although it can not be regarded as a small disturbance the calculation of steam admission flow and power generation can be simplfied under the coal-saving and power-boosting operation mode. In addition, the calculation of thermal conversion rate, generating heat rate and coal consumption rate can be simplified when the percentage of replacing point 1 extraction steam is under 60%; the calculation of thermal conversion rate, generating heat rate, coal consumption rate in waste heat utilization can be simplified no matter how the percentage of replacing extraction steam changes; the calculation of collector field area and the initial investment can also be simplified when the percentage of replacing point 1 extraction steam is under 55%. That is, the error of the caculation for the above parameters meet the engineering accuracy requirement when small disturbance algorithm is used. The above conclusion provides a theoretical reference for the optimal design and analysis of the solar-aided coal-fired power system.%光煤互补热发电系统的设计过程中通常都要进行变工况计算,由小扰动理论可知,当系统变动不足以引起汽水重新分布时,省去繁杂的变工况计算也可得到精度合乎要求的结果。该文针对太阳能辅助加热系统对热力系统影响进行了定量分析,结果表明太阳能辅助加热系

  8. Use of Auxiliary Electrode to Prevent Alkalinization of Soil in Electrokinetic Remediation

    OpenAIRE

    Mori, Yuki; Wada, Shin-ichiro

    2004-01-01

    We devised an improved electrokinetic remendiatioin method in whoch an auxiliary electrode was placed at the cathode-side end of the soil to be treated. The electric potential difference between tne anode and the auxiliary electrode was fixed constant whole that between the cathode and the auxiloary electode was controlled to make the auxiliary electode function as a secondary anode. To test the performance of the method, we carried out a bench scale remediatioin experiment on cadmium-contam...

  9. Environmental impact assessment of the incineration of municipal solid waste with auxiliary coal in China

    DEFF Research Database (Denmark)

    Zhao, Yan; Xing, Wei; Lu, Wenjing;

    2012-01-01

    The environmental impacts of waste incineration with auxiliary coal were investigated using the life-cycle-based software, EASEWASTE, based on the municipal solid waste (MSW) management system in Shuozhou City. In the current system, MSW is collected, transported, and incinerated with 250kg of coal...... per ton of waste. Based on observed environmental impacts of incineration, fossil CO2 and heavy metals were primary contributors to global warming and ecotoxicity in soil, respectively. Compared with incinerators using excess coal, incineration with adequate coal presents significant benefits......-separated and landfilled, the incineration of rest-waste presents better results on global warming, acidification, nutrient enrichment, and even ecotoxicity in soil. This process is considered a promising solution for MSW management in Shuozhou City. Weighted normalized environmental impacts were assessed based on Chinese...

  10. Stabilizing Canonical-Ensemble Calculations in the Auxiliary-Field Monte Carlo Method

    CERN Document Server

    Gilbreth, C N

    2014-01-01

    Quantum Monte Carlo methods are powerful techniques for studying strongly interacting Fermi systems. However, implementing these methods on computers with finite-precision arithmetic requires careful attention to numerical stability. In the auxiliary-field Monte Carlo (AFMC) method, low-temperature or large-model-space calculations require numerically stabilized matrix multiplication. When adapting methods used in the grand-canonical ensemble to the canonical ensemble of fixed particle number, the numerical stabilization increases the number of required floating-point operations for computing observables by a factor of the size of the single-particle model space, and thus can greatly limit the systems that can be studied. We describe an improved method for stabilizing canonical-ensemble calculations in AFMC that exhibits better scaling, and present numerical tests that demonstrate the accuracy and improved performance of the method.

  11. Generation of Enhanced and Robust bipartite optomechanical entanglement via an auxiliary qubit induced quadratic mechanical nonlinearity

    CERN Document Server

    Chakraborty, Subhadeep

    2016-01-01

    We present a scheme for obtaining steady-state optomechanical entanglement in an optomechanical system, in which the mechanical mirror is perturabatively coupled to an auxiliary qubit. The coupling between the mechanical oscillator and the single qubit results in a quadratic mechanical nonlinear term in the Hamiltonian describing the system. We find that the mechanical nonlinearity not only enhances the degree of optomechanical entanglement but also generate it at a considerably lower optomechanical coupling strength. We observe that the degree of entanglement decreases monotonically with increasing temperature. However, the maximum temperature up to which entanglement persists increase with increasing nonlinear amplitude. Thus, the bipartite entanglement in presence of the mechanical nonlinearity becomes more robust against thermal phonon fluctuations.

  12. Development of a solid oxide fuel cell (SOFC) automotive auxiliary power unit (APU) fueled by gasoline

    International Nuclear Information System (INIS)

    This paper describes the design and the development progress of a 3 to 5 auxiliary power unit (APU) based on a gasoline fueled solid oxide fuel cell (SOFC). This fuel cell was supplied reformate gas (reactant) by a partial oxidation (POx) catalytic reformer utilizing liquid gasoline and designed by Delphi Automotive Systems. This reformate gas consists mainly of hydrogen, carbon monoxide and nitrogen and was fed directly in to the SOFC stack without any additional fuel reformer processing. The SOFC stack was developed by Global Thermoelectric and operates around 700oC. This automotive APU produces power to support future 42 volt vehicle electrical architectures and loads. The balance of the APU, designed by Delphi Automotive Systems, employs a packaging and insulation design to facilitate installation and operation on-board automobiles. (author)

  13. Demand-Side Contribution to Primary Frequency Control With Wind Farm Auxiliary Control

    DEFF Research Database (Denmark)

    Gomez-Lazaro, Emilio; Munoz-Benavente, Irene; Hansen, Anca Daniela;

    2014-01-01

    Maintaining a close balance between power generation and demand is essential for sustaining the quality and reliability of a power system. Currently, due to increased renewable energy generation, frequency deviations and power fluctuations of greater concern are being introduced to the grid......, particularly in regions that are weakly interconnected with their surrounding areas, such as small islands. This paper addresses the problem of frequency control in isolated power systems with relevant inclusion of wind power generation. With this aim, we have analyzed the contribution of the demand side...... to the primary frequency control together with an auxiliary frequency control, which is carried out by variable-speed wind turbines through an additional control loop that synthesizes virtual inertia. We have evaluated both the suitability of these two additional control actions counteracting frequency deviation...

  14. 给水调节阀自动控制效果的优化%Optimization of the Automatic Control Effect of Feedwater Regulating Valve

    Institute of Scientific and Technical Information of China (English)

    俞利锋

    2012-01-01

    In order to optimize the automatic control effect of the boiler feedwater regulating valve, some factors affecting the control effect of feedwater regulating valve are analyzed and researched, such as the accuracy of parameters measurement, dynamic characteristic of drum water level, basic control principle, and the rationality of parameters processing and equipment selection. The factors affecting the automatic control are optimized, such as parameters compensation and correction, control strategy optimization, parameters reasonable filtering and equipment rational selection. Practice shows that automatic control effect is improved and equipment life is extended by conducting a series of optimization processes.%为优化锅炉给水调节阀自动控制的效果,对影响给水调节阀控制效果的参数测量的精确性、汽包水位的动态特性、基本的控制原理、参数处理和设备选用的合理性进行了分析研究.对参数的补偿修正、控制策略的优化、参数的合理滤波以及设备的合理选型等影响自动控制效果的因素进行了优化处理.实践表明,通过一系列的优化处理既能优化自动控制的效果,又能延长设备使用寿命.

  15. Parent formulations, frame-like Lagrangians, and generalized auxiliary fields

    CERN Document Server

    Grigoriev, Maxim

    2012-01-01

    We elaborate on the recently proposed Lagrangian parent formulation. In particular, we identify a natural choice of the allowed field configurations ensuring the equivalence of the parent and the starting point Lagrangians. We also analyze the structure of the generalized auxiliary fields employed in the parent formulation and establish the relationship between the parent Lagrangian and the recently proposed Lagrange structure for the unfolded dynamics. As an illustration of the parent formalism a systematic derivation of the frame-like Lagrangian for totally symmetric fields starting from the Fronsdal one is given. We also present a concise and manifestly sp(2)-symmetric form of the off-shell constraints and gauge symmetries for AdS space symmetric fields at the nonlinear level.

  16. Symbol rate identification for auxiliary amplitude modulation optical signal

    Science.gov (United States)

    Wei, Junyu; Dong, Zhi; Huang, Zhiping; Zhang, Yimeng

    2016-09-01

    In this paper, we creatively propose and demonstrate a method for symbol rate identification (SRI) of auxiliary amplitude modulation (AAM) optical signal based on asynchronous delay-tap sampling (ADTS) and average magnitude difference function (AMDF). The method can accurately estimate symbol rate and has large transmission impairments tolerance. Furthermore, it can be realized in the digital signal processor (DSP) with low logical resources because of multiplication-free. In order to improve the accuracy of SRI, the peak to valley ratio (PTVR) of AMDF is introduced into our method for blind chromatic dispersion (CD) compensation. The results of the numerical simulations show that the overall maximum SRI error is smaller 0.079% for return-to-zero (RZ) on-off keying (OOK), RZ differential phase-shift keying (DPSK), RZ differential quadrature phase-shift keying (DQPSK) and RZ 16-ary quadrature amplitude modulation (QAM) with 50% duty cycles.

  17. Glycosyl dithiocarbamates: β-selective couplings without auxiliary groups.

    Science.gov (United States)

    Padungros, Panuwat; Alberch, Laura; Wei, Alexander

    2014-03-21

    In this article, we evaluate glycosyl dithiocarbamates (DTCs) with unprotected C2 hydroxyls as donors in β-linked oligosaccharide synthesis. We report a mild, one-pot conversion of glycals into β-glycosyl DTCs via DMDO oxidation with subsequent ring opening by DTC salts, which can be generated in situ from secondary amines and CS2. Glycosyl DTCs are readily activated with Cu(I) or Cu(II) triflate at low temperatures and are amenable to reiterative synthesis strategies, as demonstrated by the efficient construction of a tri-β-1,6-linked tetrasaccharide. Glycosyl DTC couplings are highly β-selective despite the absence of a preexisting C2 auxiliary group. We provide evidence that the directing effect is mediated by the C2 hydroxyl itself via the putative formation of a cis-fused bicyclic intermediate. PMID:24548247

  18. Learning Deep Representation for Face Alignment with Auxiliary Attributes.

    Science.gov (United States)

    Zhang, Zhanpeng; Luo, Ping; Loy, Chen Change; Tang, Xiaoou

    2016-05-01

    In this study, we show that landmark detection or face alignment task is not a single and independent problem. Instead, its robustness can be greatly improved with auxiliary information. Specifically, we jointly optimize landmark detection together with the recognition of heterogeneous but subtly correlated facial attributes, such as gender, expression, and appearance attributes. This is non-trivial since different attribute inference tasks have different learning difficulties and convergence rates. To address this problem, we formulate a novel tasks-constrained deep model, which not only learns the inter-task correlation but also employs dynamic task coefficients to facilitate the optimization convergence when learning multiple complex tasks. Extensive evaluations show that the proposed task-constrained learning (i) outperforms existing face alignment methods, especially in dealing with faces with severe occlusion and pose variation, and (ii) reduces model complexity drastically compared to the state-of-the-art methods based on cascaded deep model. PMID:27046839

  19. Undersampled face recognition via robust auxiliary dictionary learning.

    Science.gov (United States)

    Wei, Chia-Po; Wang, Yu-Chiang Frank

    2015-06-01

    In this paper, we address the problem of robust face recognition with undersampled training data. Given only one or few training images available per subject, we present a novel recognition approach, which not only handles test images with large intraclass variations such as illumination and expression. The proposed method is also to handle the corrupted ones due to occlusion or disguise, which is not present during training. This is achieved by the learning of a robust auxiliary dictionary from the subjects not of interest. Together with the undersampled training data, both intra and interclass variations can thus be successfully handled, while the unseen occlusions can be automatically disregarded for improved recognition. Our experiments on four face image datasets confirm the effectiveness and robustness of our approach, which is shown to outperform state-of-the-art sparse representation-based methods.

  20. A proposal on auxiliary business insurance for peritoneal dialysis treatment

    Institute of Scientific and Technical Information of China (English)

    WANG Juan; WANG Tao; FANG Ji-qian

    2008-01-01

    Background The peritoneal dialysis (PD) therapy for end stage renal disease (ESRD) is expensive. The main reason for non-acceptance onto dialysis programs is the great cost. In the present study, we design an auxiliary business insurance program to provide the potential ESRD patients who have no access to governmental medical insurance or can not afford the remaining part besides the limited reimbursement for peritoneal dialysis therapy.Methods The information applied in this study was extracted from the medical records of 641 PD patients, who were treated in two dialysis centers of the first and the third teaching hospitals of the Peking University respectively. A collective risk model was employed to estimate the expenses on PD therapy. Survival analyses were performed to obtain the average survival time of PD patients and the average length of time from the onset of the primary disease to the beginning of PD. An annuity method was used to determine the pure premium.Results For chronic nephritis, diabetes mellitus and hyperpietic as primary diseases, the mean survival time ± standard errors were (55.1±3.7) months, (38.9±3.2) months and (61.4±4.6) months respectively, and they were significantly different from each other (all P=0.000). The expenses of whole PD therapy were 242 159.05 Yuan, 182 525.02 Yuan and 284 579.24 Yuan respectively.Conclusions An auxiliary business insurance for PD patients was designed with the pure premium for any individual who had chronic nephritis, diabetes mellitus or hyperpietic as primary disease was RMB 35.94 Yuan/year, 87.73Yuan/year or 7.71 Yuan/year respectively without considering the additional premium for coping with the business expenditures and accidental risks.

  1. Grammaticalization: The development of some English modal auxiliaries

    Directory of Open Access Journals (Sweden)

    Leonardo Véliz Campos

    2007-01-01

    Full Text Available This paper approaches the topic of Grammaticalization from a diachronic perspective, with particular emphasis on the development of some English modal auxiliaries. The first part contextualizes the topic within the filed of Cognitive Linguistics; the second, deals with a brief description of lexical and grammatical items. The third part of the paper provides some crucial information on the history of Grammaticalization. A final section outlines some of the mechanisms involved in the process of Grammaticalization together with the analysis of some English modal auxiliaries and the importance of it in when studying and understanding English as a foreign language.En éste articulo se hace una reseña de un perspectiva diacrónica a un tema llamado Gramaticalización, con particular énfasis en el desarrollo de algunos de los verbos auxiliares modales en Inglés. En la primera parte se contextualiza el tema en el campo de los estudios de la Lingüística Cognitiva y, en la segunda, se aborda la distinción entre categorías léxicas y categorías gramaticales en una breve descripción. En la tercera parte se entrega información acerca de la historia del proceso de gramaticalización. La sección final plantea algunos de los mecanismos que son parte del proceso de gramaticalización, junto con un análisis de algunos verbos auxiliares modales en inglés que resultan ser de suma importancia en el estudio y la comprensión del inglés como lengua extranjera.

  2. Auxiliary-field quantum Monte Carlo calculations of the molybdenum dimer.

    Science.gov (United States)

    Purwanto, Wirawan; Zhang, Shiwei; Krakauer, Henry

    2016-06-28

    Chemical accuracy is difficult to achieve for systems with transition metal atoms. Third row transition metal atoms are particularly challenging due to strong electron-electron correlation in localized d-orbitals. The Cr2 molecule is an outstanding example, which we previously treated with highly accurate auxiliary-field quantum Monte Carlo (AFQMC) calculations [W. Purwanto et al., J. Chem. Phys. 142, 064302 (2015)]. Somewhat surprisingly, computational description of the isoelectronic Mo2 dimer has also, to date, been scattered and less than satisfactory. We present high-level theoretical benchmarks of the Mo2 singlet ground state (X(1)Σg (+)) and first triplet excited state (a(3)Σu (+)), using the phaseless AFQMC calculations. Extrapolation to the complete basis set limit is performed. Excellent agreement with experimental spectroscopic constants is obtained. We also present a comparison of the correlation effects in Cr2 and Mo2. PMID:27369514

  3. Auxiliary-field quantum Monte Carlo calculations of the molybdenum dimer

    Science.gov (United States)

    Purwanto, Wirawan; Zhang, Shiwei; Krakauer, Henry

    2016-06-01

    Chemical accuracy is difficult to achieve for systems with transition metal atoms. Third row transition metal atoms are particularly challenging due to strong electron-electron correlation in localized d-orbitals. The Cr2 molecule is an outstanding example, which we previously treated with highly accurate auxiliary-field quantum Monte Carlo (AFQMC) calculations [W. Purwanto et al., J. Chem. Phys. 142, 064302 (2015)]. Somewhat surprisingly, computational description of the isoelectronic Mo2 dimer has also, to date, been scattered and less than satisfactory. We present high-level theoretical benchmarks of the Mo2 singlet ground state (X1Σg+) and first triplet excited state (a3Σu+), using the phaseless AFQMC calculations. Extrapolation to the complete basis set limit is performed. Excellent agreement with experimental spectroscopic constants is obtained. We also present a comparison of the correlation effects in Cr2 and Mo2.

  4. Auxiliary-field quantum Monte Carlo calculations of the molybdenum dimer

    CERN Document Server

    Purwanto, Wirawan; Krakauer, Henry

    2016-01-01

    Chemical accuracy is difficult to achieve for systems with transition metal atoms. Third row transition metal atoms are particularly challenging due to strong electron-electron correlation in localized d-orbitals. The Cr2 molecule is an outstanding example, which we previously treated with highly accurate auxiliary-field quantum Monte Carlo (AFQMC) calculations [Purwanto et al., J. Chem. Phys. 142, 064302 (2015)]. Somewhat surprisingly, computational description of the isoelectronic Mo2 dimer has also, to date, been scattered and less than satisfactory. We present high-level theoretical benchmarks of the Mo2 singlet ground state ($X ^1\\Sigma_g^+$) and first triplet excited state ($a ^3\\Sigma_u^+$), using the phaseless AFQMC calculations. Extrapolation to the complete basis set limit is performed. Excellent agreement with experimental spectroscopic constants is obtained. We also present a comparison of the correlation effects in Cr2 and Mo2.

  5. Auxiliary-field based trial wave functions in quantum Monte Carlo simulations

    Science.gov (United States)

    Chang, Chia-Chen; Rubenstein, Brenda; Morales, Miguel

    We propose a simple scheme for generating correlated multi-determinant trial wave functions for quantum Monte Carlo algorithms. The method is based on the Hubbard-Stratonovich transformation which decouples a two-body Jastrow-type correlator into one-body projectors coupled to auxiliary fields. We apply the technique to generate stochastic representations of the Gutzwiller wave function, and present benchmark resuts for the ground state energy of the Hubbard model in one dimension. Extensions of the proposed scheme to chemical systems will also be discussed. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, 15-ERD-013.

  6. Auxiliary power unit based on a solid oxide fuel cell and fuelled with diesel

    Science.gov (United States)

    Lawrence, Jeremy; Boltze, Matthias

    An auxiliary power unit (APU) is presented that is fuelled with diesel, thermally self-sustaining, and based on a solid oxide fuel cell (SOFC). The APU is rated at 1 kW electrical, and can generate electrical power after a 3 h warm-up phase. System features include a "dry" catalytic partial oxidation (CPOX) diesel reformer, a 30 cell SOFC stack with an open cathode, and a porous-media afterburner. The APU does not require a supply of external water. The SOFC stack is an outcome of a development partnership with H.C. Starck GmbH and Fraunhofer IKTS, and is discussed in detail in an accompanying paper.

  7. Modal Auxiliaries and Their Semantic Functions Used by Advanced EFL Learners

    Science.gov (United States)

    Torabiardakani, Najmeh; Khojasteh, Laleh; Shokrpour, Nasrin

    2015-01-01

    Since modal auxiliary verbs have been proved to be one of the most troublesome grammatical structures in English, the researchers of this study decided to do an analysis on the ways in which advanced EFL Iranian students use modal auxiliaries focusing specially on nine modals' semantic functions. Consequently, was conducted based on the following…

  8. Conceptual design of passive containment cooling system with air holdup tanks in the concrete containment of improved APR+

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Byong Guk; NO, Hee Cheon, E-mail: hcno@kaist.ac.kr

    2014-02-15

    Highlights: • Conceptual design of passive containment cooling system (PCCS) based on APR+ is proposed. • Decay heat removal rate is to be maximized by introducing air holdup tanks (AHT). • Only air is transported into the AHT decreasing air mass fraction near HXs inside containment and increasing heat transfer rates. • Large AHT volume gives significantly higher heat removal rate. • External HXs have merits over in-tube HXs for long term cooling. - Abstract: The accident of the Fukushima nuclear power plant emphasized passive systems against prolonged station blackout. This paper aims at conceptual design of passive containment cooling system (PCCS) based on APR+, an advanced PWR developed in Korea with passive auxiliary feedwater system (PAFS). In the design, decay heat removal rate is to be maximized by introducing air holdup tanks (AHT). The AHT is an isolated space disposed above IRWST and is connected to the containment free space by vent lines through IRWST water and PAFS heat exchangers (HXs), where steam generated by decay heat is condensed. Since a lot of steam is condensed through in-tube HXs and IRWST water, air is mainly transported into the AHT decreasing air mass fraction near HXs inside containment and increasing heat transfer rates. Several design options (AHT volume, flow distribution in vent lines, HX types) are evaluated via scoping analysis. The scoping analysis had proved that AHT (>10% containment volume) decreased the required number of PCCS HXs to be installed less than a half, failure of valves caused marginal increase in HXs to be installed, and external HXs had merits over in-tube HXs for long term cooling.

  9. Solid Oxide Fuel Cell/Gas Turbine Hybrid Cycle Technology for Auxiliary Aerospace Power

    Science.gov (United States)

    Steffen, Christopher J., Jr.; Freeh, Joshua E.; Larosiliere, Louis M.

    2005-01-01

    A notional 440 kW auxiliary power unit has been developed for 300 passenger commercial transport aircraft in 2015AD. A hybrid engine using solid-oxide fuel cell stacks and a gas turbine bottoming cycle has been considered. Steady-state performance analysis during cruise operation has been presented. Trades between performance efficiency and system mass were conducted with system specific energy as the discriminator. Fuel cell performance was examined with an area specific resistance. The ratio of fuel cell versus turbine power was explored through variable fuel utilization. Area specific resistance, fuel utilization, and mission length had interacting effects upon system specific energy. During cruise operation, the simple cycle fuel cell/gas turbine hybrid was not able to outperform current turbine-driven generators for system specific energy, despite a significant improvement in system efficiency. This was due in part to the increased mass of the hybrid engine, and the increased water flow required for on-board fuel reformation. Two planar, anode-supported cell design concepts were considered. Designs that seek to minimize the metallic interconnect layer mass were seen to have a large effect upon the system mass estimates.

  10. Application of flow network models of SINDA/FLUINT{sup TM} to a nuclear power plant system thermal hydraulic code

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ji Bum [Institute for Advanced Engineering, Yongin (Korea, Republic of); Park, Jong Woon [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    In order to enhance the dynamic and interactive simulation capability of a system thermal hydraulic code for nuclear power plant, applicability of flow network models in SINDA/FLUINT{sup TM} has been tested by modeling feedwater system and coupling to DSNP which is one of a system thermal hydraulic simulation code for a pressurized heavy water reactor. The feedwater system is selected since it is one of the most important balance of plant systems with a potential to greatly affect the behavior of nuclear steam supply system. The flow network model of this feedwater system consists of condenser, condensate pumps, low and high pressure heaters, deaerator, feedwater pumps, and control valves. This complicated flow network is modeled and coupled to DSNP and it is tested for several normal and abnormal transient conditions such turbine load maneuvering, turbine trip, and loss of class IV power. The results show reasonable behavior of the coupled code and also gives a good dynamic and interactive simulation capabilities for the several mild transient conditions. It has been found that coupling system thermal hydraulic code with a flow network code is a proper way of upgrading simulation capability of DSNP to mature nuclear plant analyzer (NPA). 5 refs., 10 figs. (Author)

  11. RELAP5 code study of ROSA/LSTF validation tests for PWR safety system using SG secondary-side depressurization

    International Nuclear Information System (INIS)

    RELAP5 code post-test analyses were performed on two ROSA/large scale test facility (LSTF) validation tests for PWR safety system that simulated cold leg small-break loss-of-coolant accidents with 8-in. or 4-in. diameter break using steam generator (SG) secondary-side depressurization. The SG depressurization was initiated by fully opening the depressurization valves in both SGs a little after a safety injection signal. Auxiliary feedwater injection was done into the secondary-side of both SGs thereafter. In the 8-in. break test, loop seal clearing occurred and then core uncovery and heatup took place by boil-off. Core collapsed liquid level recovered after the initiation of accumulator (ACC) coolant injection, and long-term core cooling was ensured by the actuation of low-pressure injection (LPI) system. In the 4-in. break test, on the other hand, no core uncovery and heatup happened due to the coolant injection from the ACC and LPI systems. Adjustment of break discharge coefficient for two-phase discharge flow predicted the break flow rate reasonably well. The code predicted well the overall trend of the major thermal-hydraulic response observed in the two LSTF tests. The code, however, overpredicted the peak cladding temperature (PCT) because of underprediction of the core collapsed liquid level due to inadequate prediction of the ACC flow rate in the 8-in. break case. Sensitivity analyses with the RELAP5 code indicated that a time delay for the SG depressurization start and break discharge coefficient for two-phase discharge flow affect the PCT significantly in the 8-in. break case. (author)

  12. Auxiliary transportation mode in a fully-mechanized face in a nearly horizontal thin coal seam

    Institute of Scientific and Technical Information of China (English)

    Wang Chen; Tu Shihao; Zhang Lei; Yang Qianlong; Tu Hongsheng

    2015-01-01

    On fully-mechanized faces in nearly horizontal thin coal seams (NHTCS), the selection of the auxiliary transportation mode is difficult. Generally, auxiliary transportation mainly includes trackless or rail transportation. Combined with a familiar NHTCS fully-mechanized face, a multi-attribute decision-making model was set up for the decision. The index weight was objectively determined with the fuzzy number and entropy method. The priority order of auxiliary transportation modes was obtained from the Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE). The results show that: the net flow of the mode can be expressed by the function of the surrounding rock deformation of the roadway, the dimension of equipment and the thickness of the coal seam;Based on the cost type index, there is a positive correlation between the net flow with the height and width of the trackless aux-iliary transportation equipment, respectively. The trackless auxiliary transportation equipment selection principle should be‘height first then width”. Combined with the field application of the trackless auxil-iary transportation in Liangshuijing coal mine, the proper method to achieve the safe and high-efficient exploitation of a NHTCS fully-mechanized face is trackless tyred vehicle auxiliary transportation.

  13. A magnetorheological clutch for efficient automotive auxiliary device actuation

    Directory of Open Access Journals (Sweden)

    F. Bucchi

    2013-01-01

    Full Text Available In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design, testing and application of a magnetorheological clutch (MR is proposed, aimed at disengaging the vacuum pump, which draws in air from the power-brake booster chamber, in order to reduce the device power absorption. Several clutch preliminary studies done to choose the clutch geometry and the magnetic field supply are illustrated. The final choice consisted in an MR clutch with permanent magnet, which satisfied size, torque and fail-safe specifications. The clutch characteristics, in terms of torque versus slip, were obtained experimentally for three different clutch prototypes on an ad-hoc developed test bench.As result of a preliminary simulation, a comparison between the power absorption of a current production vacuum pump, an innovative vacuum pump and both vacuum pumps coupled with the MR clutch is presented. The New European Driving Cycle is considered for simulating the vacuum pump operation both in urban and highway driving. Results show that the use of the innovative vacuum pump reduces the device consumption of about 35%, whereas the use of MR clutch coupled with the innovative vacuum pump reduces it up to about 44% in urban driving and 50% in highway driving.

  14. Adaptive mean-shift tracking with auxiliary particles.

    Science.gov (United States)

    Wang, Junqiu; Yagi, Yasushi

    2009-12-01

    We present a new approach for robust and efficient tracking by incorporating the efficiency of the mean-shift algorithm with the multihypothesis characteristics of particle filtering in an adaptive manner. The aim of the proposed algorithm is to cope with problems that were brought about by sudden motions and distractions. The mean-shift tracking algorithm is robust and effective when the representation of a target is sufficiently discriminative, the target does not jump beyond the bandwidth, and no serious distractions exist. We propose a novel two-stage motion estimation method that is efficient and reliable. If a sudden motion is detected by the motion estimator, some particle-filtering-based trackers can be used to outperform the mean-shift algorithm, at the expense of using a large particle set. In our approach, the mean-shift algorithm is used, as long as it provides reasonable performance. Auxiliary particles are introduced to cope with distractions and sudden motions when such threats are detected. Moreover, discriminative features are selected according to the separation of the foreground and background distributions when threats do not exist. This strategy is important, because it is dangerous to update the target model when the tracking is in an unsteady state. We demonstrate the performance of our approach by comparing it with other trackers in tracking several challenging image sequences.

  15. LOFT integral test system final safety analysis report

    International Nuclear Information System (INIS)

    Safety analyses are presented for the following LOFT Reactor systems: engineering safety features; support buildings and facilities; instrumentation and controls; electrical systems; and auxiliary systems. (JWR)

  16. Analysis of nuclear piping system seismic tests with conventional and energy absorbing supports

    Energy Technology Data Exchange (ETDEWEB)

    Park, Y.; DeGrassi, G.; Hofmayer, C.; Bezler, P. [Brookhaven National Lab., Upton, NY (United States); Chokshi, N. [Nuclear Regulatory Commission, Washington, DC (United States)

    1997-04-01

    Large-scale models of main steam and feedwater piping systems were tested on the shaking table by the Nuclear Power Engineering Cooperation (NUPEC) of Japan, as part of the Seismic Proving Test Program. This paper describes the linear and nonlinear analyses performed by NRC/BNL and compares the results to the test data.

  17. On the implementation of an auxiliary pantograph for speed increase on existing lines

    Science.gov (United States)

    Liu, Zhendong; Jönsson, Per-Anders; Stichel, Sebastian; Rønnquist, Anders

    2016-08-01

    The contact between pantograph and catenary at high speeds suffers from high dynamic contact force variation due to stiffness variations and wave propagation. To increase operational speed on an existing catenary system, especially for soft catenary systems, technical upgrading is usually necessary. Therefore, it is desirable to explore a more practical and cost-saving method to increase the operational speed. Based on a 3D pantograph-catenary finite element model, a parametric study on two-pantograph operation with short spacing distances at high speeds shows that, although the performance of the leading pantograph gets deteriorated, the trailing pantograph feels an improvement if pantographs are spaced at a proper distance. Then, two main positive effects, which can cause the improvement, are addressed. Based on a discussion on wear mechanisms, this paper suggests to use the leading pantograph as an auxiliary pantograph, which does not conduct any electric current, to minimise additional wear caused by the leading pantograph. To help implementation and achieve further improvement under this working condition, this paper investigates cases with optimised uplift force on the leading pantograph and with system parameter deviations. The results show that the two positive effects still remain even with some system parameter deviations. About 30% of speed increase should be possibly achieved still sustaining a good dynamic performance with help of the optimised uplift force.

  18. Ocean Surface Topography Mission (OSTM) /Jason-2: Auxiliary Files (NODC Accession 0044983)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains the data descriptions for the OSTM/Jason-2 Auxiliary data files, which is served through the NOAA/NESDIS Comprehensive Large Array-data...

  19. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    OSCAR,DEBBY S.; WALKER,SHARON ANN; HUNTER,REGINA LEE; WALKER,CHERYL A.

    1999-12-01

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2.

  20. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    International Nuclear Information System (INIS)

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2

  1. A Method of Auxiliary Sources Approach for Modelling the Impact of Ground Planes on Antenna

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2006-01-01

    The Method of Auxiliary Sources (MAS) is employed to model the impact of finite ground planes on the radiation from antennas. Two different antenna test cases are shown and the calculated results agree well with reference measurements......The Method of Auxiliary Sources (MAS) is employed to model the impact of finite ground planes on the radiation from antennas. Two different antenna test cases are shown and the calculated results agree well with reference measurements...

  2. Auxiliary heating of a theta-pinch plasma by radial magnetoacoustic standing waves

    International Nuclear Information System (INIS)

    Auxiliary heating of a linear theta-pinch plasma column by an externally driven radial magnetoacoustic oscillation has been experimentally investigated. The axial field of the theta pinch was modulated in time at the frequency of the plasma's fundamental radial magnetoacoustic oscillation. The dissipation in the plasma column was sufficient to transfer into the plasma at least 9% of the energy stored in the auxiliary capacitor bank used to drive the oscillation

  3. Design-based random permutation models with auxiliary information(¶)

    Science.gov (United States)

    Li, Wenjun; Stanek, Edward J; Singer, Julio M

    2012-01-01

    We extend the random permutation model to obtain the best linear unbiased estimator of a finite population mean accounting for auxiliary variables under simple random sampling without replacement (SRS) or stratified SRS. The proposed method provides a systematic design-based justification for well-known results involving common estimators derived under minimal assumptions that do not require specification of a functional relationship between the response and the auxiliary variables. PMID:23645951

  4. A review of high-temperature polymer electrolyte membrane fuel-cell (HT-PEMFC)-based auxiliary power units for diesel-powered road vehicles

    Science.gov (United States)

    Liu, Yongfeng; Lehnert, Werner; Janßen, Holger; Samsun, Remzi Can; Stolten, Detlef

    2016-04-01

    This paper presents an extensive review of research on the development of auxiliary power units with enhanced reformate tolerance for high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Developments in diesel reforming for fuel cells as auxiliary power units (APUs), single fuel cells and stacks and systems are outlined in detail and key findings are presented. Summaries of HT-PEMFC APU applications and start-up times for HT-PEMFC systems are then given. A summary of cooling HT-PEMFC stacks using a classic schematic diagram of a 24-cell HT-PEMFC stack, with a cooling plate for every third cell, is also presented as part of a stack analysis. Finally, a summary of CO tolerances for fuel cells is given, along with the effects of different CO volume fractions on polarization curves, the fraction of CO coverage, hydrogen coverage, anode overpotential and cell potential.

  5. Simulation of engine auxiliary drive V-belt slip motion. Part 1. Development of belt slip model; Engine hoki V belt slip kyodo no simulation. 1. Belt slip model no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kurisu, T. [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    V-belts are widely used for driving auxiliary components of an engine. Inadequet design of such belt system sometimes results in troubles such as belt squeak, side rubber separation and/or bottom rubber crack. However, there has been no design tools which can predict belt slip quantitatively. The author developed a motion simulation program of Auxiliary Drive V-Belt System considering belt slip. The program showed good prediction accuracy for belt slip motion. This paper describes the simulation model. 1 ref., 12 figs.

  6. Solid Oxide Fuel Cell Development for Auxiliary Power in Heavy Duty Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Daniel T. Hennessy

    2010-06-15

    Changing economic and environmental needs of the trucking industry is driving the use of auxiliary power unit (APU) technology for over the road haul trucks. The trucking industry in the United States remains the key to the economy of the nation and one of the major changes affecting the trucking industry is the reduction of engine idling. Delphi Automotive Systems, LLC (Delphi) teamed with heavy-duty truck Original Equipment Manufacturers (OEMs) PACCAR Incorporated (PACCAR), and Volvo Trucks North America (VTNA) to define system level requirements and develop an SOFC based APU. The project defines system level requirements, and subsequently designs and implements an optimized system architecture using an SOFC APU to demonstrate and validate that the APU will meet system level goals. The primary focus is on APUs in the range of 3-5 kW for truck idling reduction. Fuels utilized were derived from low-sulfur diesel fuel. Key areas of study and development included sulfur remediation with reformer operation; stack sensitivity testing; testing of catalyst carbon plugging and combustion start plugging; system pre-combustion; and overall system and electrical integration. This development, once fully implemented and commercialized, has the potential to significantly reduce the fuel idling Class 7/8 trucks consume. In addition, the significant amounts of NOx, CO2 and PM that are produced under these engine idling conditions will be virtually eliminated, inclusive of the noise pollution. The environmental impact will be significant with the added benefit of fuel savings and payback for the vehicle operators / owners.

  7. Exergo-Ecological Assessment Of Auxiliary Fuel Injection Into Blast-Furnace

    Directory of Open Access Journals (Sweden)

    Stanek W.

    2015-06-01

    Full Text Available Metallurgy represents complex technological chain supplied with different kinds of primary resources. Iron metallurgy based on blast-furnace process, dominates in world steel production. Metallurgical coke is the basic fuel in this case. Its production is connected with several environmental disadvantageous impacts. One of them is the extended production chain from primary energy to final energy. The reduction of coke consumption in the process can be achieved e.g. by injection of auxiliary fuels or increasing the thermal parameters in the process. In present injection of pulverised coal dominates while recirculation of top-gas seems to be future technology. However, the latter one requires the CO2 removal that additionally extended the production chain. The evaluation of resources management in complex energy-technological systems required application of advanced method based on thermodynamics. In the paper the system exergo-ecological assessment of pulverised coal injection into blast-furnace and top-gas recirculation has been applied. As a comparative criterion the thermo-ecological cost has been proposed.

  8. Regulatable and Modulable Background Expression Control in Prokaryotic Synthetic Circuits by Auxiliary Repressor Binding Sites.

    Science.gov (United States)

    Merulla, Davide; van der Meer, Jan Roelof

    2016-01-15

    Expression control in synthetic genetic circuitry, for example, for construction of sensitive biosensors, is hampered by the lack of DNA parts that maintain ultralow background yet achieve high output upon signal integration by the cells. Here, we demonstrate how placement of auxiliary transcription factor binding sites within a regulatable promoter context can yield an important gain in signal-to-noise output ratios from prokaryotic biosensor circuits. As a proof of principle, we use the arsenite-responsive ArsR repressor protein from Escherichia coli and its cognate operator. Additional ArsR operators placed downstream of its target promoter can act as a transcription roadblock in a distance-dependent manner and reduce background expression of downstream-placed reporter genes. We show that the transcription roadblock functions both in cognate and heterologous promoter contexts. Secondary ArsR operators placed upstream of their promoter can also improve signal-to-noise output while maintaining effector dependency. Importantly, background control can be released through the addition of micromolar concentrations of arsenite. The ArsR-operator system thus provides a flexible system for additional gene expression control, which, given the extreme sensitivity to micrograms per liter effector concentrations, could be applicable in more general contexts.

  9. Concerted action of NIC relaxase and auxiliary protein MobC in RA3 plasmid conjugation.

    Science.gov (United States)

    Godziszewska, Jolanta; Moncalián, Gabriel; Cabezas, Matilde; Bartosik, Aneta A; de la Cruz, Fernando; Jagura-Burdzy, Grazyna

    2016-08-01

    Conjugative transfer of the broad-host-range RA3 plasmid, the archetype of the IncU group, relies on the relaxase NIC that belongs to the as yet uncharacterized MOBP4 subfamily. NIC contains the signature motifs of HUH relaxases involved in Tyr nucleophilic attack. However, it differs in the residue involved in His activation for cation coordination and was shown here to have altered divalent cation requirements. NIC is encoded in the mobC-nic operon preceded directly by oriT, where mobC encodes an auxiliary transfer protein with a dual function: autorepressor and stimulator of conjugative transfer. Here an interplay between MobC and NIC was demonstrated. MobC is required for efficient NIC cleavage of oriT in supercoiled DNA whereas NIC assists MobC in repression of the mobC-nic operon. A 7-bp arm of IR3 (IR3a) was identified as the binding site for NIC and the crucial nucleotides in IR3a for NIC recognition were defined. Fully active oriTRA3 was delineated to a 47-bp DNA segment encompassing a conserved cleavage site sequence, the NIC binding site IR3a and the MobC binding site OM . This highly efficient RA3 conjugative system with defined requirements for minimal oriT could find ample applications in biotechnology and computational biology where simple conjugative systems are needed.

  10. Entanglement and the fermion sign problem in auxiliary field quantum Monte Carlo simulations

    Science.gov (United States)

    Broecker, Peter; Trebst, Simon

    2016-08-01

    Quantum Monte Carlo simulations of fermions are hampered by the notorious sign problem whose most striking manifestation is an exponential growth of sampling errors with the number of particles. With the sign problem known to be an NP-hard problem and any generic solution thus highly elusive, the Monte Carlo sampling of interacting many-fermion systems is commonly thought to be restricted to a small class of model systems for which a sign-free basis has been identified. Here we demonstrate that entanglement measures, in particular the so-called Rényi entropies, can intrinsically exhibit a certain robustness against the sign problem in auxiliary-field quantum Monte Carlo approaches and possibly allow for the identification of global ground-state properties via their scaling behavior even in the presence of a strong sign problem. We corroborate these findings via numerical simulations of fermionic quantum phase transitions of spinless fermions on the honeycomb lattice at and below half filling.

  11. Design, construction and test run of a two-tonne capacity solar rice dryer with rice-husk-fired auxiliary heater

    International Nuclear Information System (INIS)

    The design and construction details of a two-tonne per batch capacity natural-circulation solar rice dryer and the highlights of the design of its rice-husk-fired auxiliary heating system which is still under construction are presented. The dryer measures approximately 17.7m long by 9.8m wide by 6m high. Preliminary results of a test run on the solar dryer section only is reported. (author). 5 refs, 3 figs

  12. Auxiliary-field quantum Monte Carlo study of first- and second-row post-d elements

    CERN Document Server

    Al-Saidi, W A; Zhang, S; Krakauer, Henry; Zhang, Shiwei

    2006-01-01

    A series of calculations for the first- and second-row post-d elements (Ga-Br and In-I) are presented using the phaseless auxiliary-field quantum Monte Carlo (AF QMC) method. This method is formulated in a Hilbert space defined by any chosen one-particle basis, and maps the many-body problem into a linear combination of independent-particle solutions with external auxiliary fields. The phase/sign problem is handled approximately by the phaseless formalism using a trial wave function, which in our calculations was chosen to be the Hartree-Fock solution. We used the consistent correlated basis sets of Peterson and coworkers, which employ a small core relativistic pseudopotential. The AF QMC results are compared with experiment and with those from density-functional (GGA and B3LYP) and coupled-cluster CCSD(T) calculations. The AF QMC total energies agree with CCSD(T) to within a few milli-hartrees across the systems and over several basis sets. The calculated atomic electron affinities, ionization energies, and ...

  13. Incorporating Auxiliary Information in Collaborative Filtering Data Update with Privacy Preservation

    Directory of Open Access Journals (Sweden)

    Xiwei Wang

    2014-05-01

    Full Text Available Online shopping has become increasingly popular in recent years. More and more people are willing to buy products through Internet instead of physical stores. For promotional purposes, almost all online merchants provide product recommendations to their returning customers. Some of them ask professional recommendation service providers to help develop and maintain recommender systems while others need to share their data with similar shops for better product recommendations. There are two issues, (1 how to protect customers’ privacy while retaining data utility before they release the data to the third parties; (2 based on (1, how to handle data growth efficiently. In this paper, we propose a NMF (Nonnegative Matrix Factorization-based data update approach in collaborative filtering (CF that solves the problems. The proposed approach utilizes the intrinsic property of NMF to distort the data for protecting user’s privacy. In addition, the user and item auxiliary information is taken into account in incremental nonnegative matrix tri-factorization to help improve the data utility. Experiments on three different datasets (MovieLens, Sushi and LibimSeTi are conducted to examine the proposed approach. The results show that our approach can quickly update the new data and provide both high level privacy protection and good data utility.

  14. Fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Y.; Wang, W. X.; LeBlanc, B. P.; Guttenfelder, W.; Kaye, S. M.; Ethier, S.; Mazzucato, E.; Bell, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lee, K. C. [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Domier, C. W. [University of California at Davis, Davis, California 95616 (United States); Smith, D. R. [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Yuh, H. [Nova Photonics, Inc., Princeton, New Jersey 08540 (United States)

    2015-11-15

    In this letter, we report the first observation of the fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus eXperiment [Ono et al., Nucl. Fusion 40, 557 (2000)]. The observation was made in a set of RF-heated L-mode plasmas with toroidal magnetic field of 0.55 T and plasma current of 300 kA. It is observed that electron-scale turbulence spectral power (measured with a high-k collective microwave scattering system) decreases significantly following fast cessation of RF heating that occurs in less than 200 μs. The large drop in the turbulence spectral power has a short time delay of about 1–2 ms relative to the RF cessation and happens on a time scale of 0.5–1 ms, much smaller than the energy confinement time of about 10 ms. Power balance analysis shows a factor of about 2 decrease in electron thermal diffusivity after the sudden drop of turbulence spectral power. Measured small changes in equilibrium profiles across the RF cessation are unlikely able to explain this sudden reduction in the measured turbulence and decrease in electron thermal transport, supported by local linear stability analysis and both local and global nonlinear gyrokinetic simulations. The observations imply that nonlocal flux-driven mechanism may be important for the observed turbulence and electron thermal transport.

  15. The modeling of a standalone solid-oxide fuel cell auxiliary power unit

    Science.gov (United States)

    Lu, N.; Li, Q.; Sun, X.; Khaleel, M. A.

    In this research, a Simulink model of a standalone vehicular solid-oxide fuel cell (SOFC) auxiliary power unit (APU) is developed. The SOFC APU model consists of three major components: a controller model; a power electronics system model; and an SOFC plant model, including an SOFC stack module, two heat exchanger modules, and a combustor module. This paper discusses the development of the nonlinear dynamic models for the SOFC stacks, the heat exchangers and the combustors. When coupling with a controller model and a power electronic circuit model, the developed SOFC plant model is able to model the thermal dynamics and the electrochemical dynamics inside the SOFC APU components, as well as the transient responses to the electric loading changes. It has been shown that having such a model for the SOFC APU will help design engineers to adjust design parameters to optimize the performance. The modeling results of the SOFC APU heat-up stage and the output voltage response to a sudden load change are presented in this paper. The fuel flow regulation based on fuel utilization is also briefly discussed.

  16. A CAE package for design of auxiliary buildings in nuclear power plants

    International Nuclear Information System (INIS)

    Nuclear power plants have a large number of auxiliary buildings housing various services and control systems in addition to the main reactor building. These are usually of the framed construction of two or three floors falling under seismic class I or II. Class I structures have to be qualified for seismic forces of intensity as given by SSE (safe shutdown earthquake) for three orthogonal components acting simultaneously while class II structures need to be qualified for seismic forces of intensity as given by OBE (operating basis earthquake) for two component motion-one horizontal and one vertical acting simultaneously. The seismic analysis of these buildings is carried out using the BLOCK model. For the analysis of three component motion, USNRC R.G. 1.92 permits time history method of analysis and timewise combination of responses of the three components in the proper phases. However, such a method of analysis is uneconomical for the buildings in question, more so when the layouts of such buildings during the planning phases undergo quite a few revisions necessitating reanalysis. As such, the response spectrum method of analysis is adopted for each directional component and the responses to the three component excitation are combined by adopting the SRSS criteria

  17. Characterization of an aerosol sample from the auxiliary building of the Three Mile Island reactor.

    Science.gov (United States)

    Kanapilly, G M; Stanley, J A; Newton, G J; Wong, B A; DeNee, P B

    1983-11-01

    Analyses for radioisotopic composition and dissolution characteristics were performed on an aerosol filter sample collected for a week by an air sampler located in the auxiliary building of the Three Mile Island nuclear reactor. The major radioisotopes found on the filter were 89Sr, 90Sr, 134Cs and 137Cs. Greater than 90% of both 89-90Sr and 134-137Cs dissolved within 48 hr in an in vitro test system. Scanning electron microscopic analyses showed the presence of respirable size particles as well as larger particles ranging up to 10 micron in diameter. The major matrix components were Fe, Ca, S, Mg, Al and Si. Although the radionuclides were present in a heterogeneous matrix, they were in a soluble form. This information enables a better evaluation of bioassay data and predictions of dose distribution resulting from an inhalation exposure to this aerosol. Further, the combination of techniques used in this study may be applicable to the characterization of other aerosols of unknown composition.

  18. Auxiliary power unit noise of Boeing B737 and B747 aircraft

    Science.gov (United States)

    Kwan, Jimmy S. W.; Yang, S. J. Eric

    Most modern civil aircraft have an Auxiliary Power Unit (APU) which provides compressed air for engine starting and the air-conditioning system on ground and electrical power for aircraft use both on-ground and in-fligth. It is basically a gas turbine engine and it consists of a compressor section, a turbine section, and an accessory drive section. For Boeing B737 and B747 aircraft, the APU is located inside a compartment in the tail section of the aircraft and is completely enclosed by a sound-reduction fire-proof titanium shroud. APU noise is one of the major noise sources at many airports and is extremely important for a densely populated city such as Hong Kong. The noise from APU can affect many people, including ground crew aircraft maintenance staff, and people living in the vicinity of the airport. However, there is very little information available in the literature about APU noise. This paper describes the noise measurement method and presents the measurement results for APUs of one B747 and two B737 aircraft under both 'loaded' and 'no-load' conditions.

  19. Development and implementation of thermal signature testing protocol of auxiliary power unit (APU) and diesel tractor

    Science.gov (United States)

    Jenkins, Chelsea L.; Bourne, Stefanie M.; Rowley, Matthew J.; Miles, Jonathan J.

    2004-04-01

    Thermal signature may be one of the defining factors in determining the applicability of fuel cell auxiliary power unit (APU) technology in military applications. Thermal characterization is important for military applications given that identification and detection may be accomplished through observation of its thermal signature. The operating modes and power takeoff operations of a vehicle will likely determine the thermal profile. The objective of our study was to develop and implement a protocol for quantifying the thermal characteristics of a methanol fuel cell and an idling tractor engine under representative characteristic operations. APU thermal characteristics are a special case for which standardized testing procedures do not presently exist. A customized testing protocol was developed and applied that is specific to an APU-equipped vehicle. Initial testing was conducted on the methanol APU-equipped Freightliner tractor using a high-performance radiometric infrared system. The APU profile calls for a series of infrared images to be collected at three different viewing angles and two different elevations under various loads. The diesel engine was studied in a similar fashion using seven different viewing angles and two different elevations. Raw data collected according to the newly developed methodology provided the opportunity for computer analysis and thermal profiling of both the fuel cell and the diesel engine.

  20. Application of ultrasonic techniques in feedwater flow measurement of nuclear power plant%超声波技术在核电厂给水流量测量中的应用

    Institute of Scientific and Technical Information of China (English)

    王旭; 张赫男

    2012-01-01

    为了解决差压式流量计在主给水流量测量中存在的问题,将超声波技术应用到主给水流量测量中.开展了主给水流量精度对于核电厂反应堆热功率计算及其不确定度影响的分析,总结了国内外核电厂通过提高主给水流量测量精度的方式进行核电厂小幅度功率提升的研究成果和实践经验.分析了国内在建的AP1000核电厂中,通过采用超声波流量计进行主给水流量测量以及进行小幅度功率提升项目的意义、可行性、需要开展的工作以及实施该项目潜在的收益和风险.研究结果表明,基于超声波技术完成主给水流量测量,可以实现AP1000核电厂的小幅度功率提升,同时可以使核电厂更加安全、稳定和有效地运行.%In order to solve the problems of differential pressure flow meter used in feedwater flow measurement,the ultrasonic flow meter to measure feedwater flow was investigated. After the analysis of the relation between reactor core thermal power calculation uncertainty and feedwater flow measurement accuracy,the successful experience of measurement uncertainty recapture power uprates(MUR) projects was studied. The feasibility, potential profit and risk of using ultrasonic flow meter and performing MUR project in AP1000 nuclear power plant (NPP)were evaluated. The analysis results indicate that the MUR project in AP1000 NPP is feasible based on the feedwater ultrasonic flow meter, and the safety, operation performance of the plant will be improved.

  1. Simplified technique for auxiliary orthotopic liver transplantation using a whole graft

    Science.gov (United States)

    ROCHA-SANTOS, Vinicius; NACIF, Lucas Souto; PINHEIRO, Rafael Soares; DUCATTI, Liliana; ANDRAUS, Wellington; D'ALBURQUERQUE, Luiz Carneiro

    2015-01-01

    Background Acute liver failure is associated with a high mortality rate and the main purposes of treatment are to prevent cerebral edema and infections, which often are responsible for patient death. The orthotopic liver transplantation is the gold standard treatment and improves the 1-year survival. Aim To describe an alternative technique to auxiliary liver transplant on acute liver failure. Method Was performed whole auxiliary liver transplantation as an alternative technique for a partial auxiliary liver transplantation using a whole liver graft from a child removing the native right liver performed a right hepatectomy. The patient met the O´Grady´s criteria and the rational to indicate an auxiliary orthotopic liver transplantation was the acute classification without hemodynamic instability or renal failure in a patient with deterioration in consciousness. Results The procedure improved liver function and decreased intracranial hypertension in the postoperative period. Conclusion This technique can overcome some postoperative complications that are associated with partial grafts. As far as is known, this is the first case of auxiliary orthotopic liver transplantation in Brazil. PMID:26176253

  2. Environmental practices of the auxiliary companies to the Spanish automobile industry

    Science.gov (United States)

    González-Torre, Pilar L.; González, Beatriz A.; Gupta, Surendra M.

    2005-11-01

    The automobile manufacturing industry plays a very important role in a country's economy. The importance of automobile manufacturing industry lies in its sheer size and complexity in terms of the direct and indirect influence it commands across many other industries. While millions of people are employed in the automobile manufacturing industry, it is estimated that more than two and half times that number are employed in the auxiliary companies that supply parts to the automobile manufacturing companies. The auxiliary companies represent a group of businesses of various sizes, types, and geographical locations, producing a vast variety of products ranging from the very simple to the extremely intricate. In this study, the current environmental practices of management in the core Spanish auxiliary companies that do business with the automobile manufacturing industry (and thus form a large part of the automobile manufacturing industry's supply chain) are investigated. We show that while automobile manufacturing companies are under scrutiny to become more and more environmentally friendly, not only at their manufacturing stage but also at their products' useful and EOL stages, there appears to be no such burden on the auxiliary companies. Our conclusion is based on an elaborate survey conducted during the fall of 2004 of Spanish auxiliary companies with questions about the characteristics, environmental practices and reverse logistics related activities carried out by the companies.

  3. Classifications of central solar domestic hot water systems

    Science.gov (United States)

    Guo, J. Y.; Hao, B.; Peng, C.; Wang, S. S.

    2016-08-01

    Currently, there are many means by which to classify solar domestic hot water systems, which are often categorized according to their scope of supply, solar collector positions, and type of heat storage tank. However, the lack of systematic and scientific classification as well as the general disregard of the thermal performance of the auxiliary heat source is important to DHW systems. Thus, the primary focus of this paper is to determine a classification system for solar domestic hot water systems based on the positions of the solar collector and auxiliary heating device, both respectively and in combination. Field-testing data regarding many central solar DHW systems demonstrates that the position of the auxiliary heat source clearly reflects the operational energy consumption. The consumption of collective auxiliary heating hot water system is much higher than individual auxiliary heating hot water system. In addition, costs are significantly reduced by the separation of the heat storage tank and the auxiliary heating device.

  4. Comparison of collective Thomson scattering signals due to fast ions in ITER scenarios with fusion and auxiliary heating

    DEFF Research Database (Denmark)

    Salewski, Mirko; Asunta, O.; Eriksson, L.-G.;

    2009-01-01

    to the alpha population in these frequency ranges. The exceptions are limited regions in space with some non-negligible signal due to beam ions or fast He-3 which give rise to about 30% and 10-20% of the CTS signal, respectively. In turn, the dominance of the alpha contribution implies that the effects...... scattering (CTS) signal for the proposed CTS diagnostic in ITER. It is of interest to determine the contributions of these fast ion populations to the CTS signal for large Doppler shifts of the scattered radiation since conclusions can mostly be drawn for the dominant contributor. In this study, distribution...... functions of fast ions generated by NBI and ICRH are calculated for a steady-state ITER burning plasma equilibrium with the ASCOT and PION codes, respectively. The parameters for the auxiliary heating systems correspond to the design currently foreseen for ITER. The geometry of the CTS system for ITER...

  5. Color modeling of stratified pictorial layers using the radiative transfer equation solved by the auxiliary function method.

    Science.gov (United States)

    Latour, G; Elias, M; Frigerio, J M

    2007-10-01

    The diffuse reflectance spectra and the trichromatic coordinates of diffusing stratified paints are modeled. Each layer contains its own pigments, and their optical properties are first determined from experiments. The radiative transfer equation is then solved by the auxiliary function method for modeling the total light scattered by the stratified systems. The results are in good agreement with experimental spectra and validate the modeling. The calculations are then applied on the same stratified systems to study the influence of the observation angle in a bidirectional configuration and to study the influence of the thickness of the layers in a given configuration. In both cases, the reflectance spectra and the trichromatic coordinates are calculated and compared.

  6. Engineering aspects and hardware verification of a volume producable solid oxide fuel cell stack design for diesel auxiliary power units

    Science.gov (United States)

    Stelter, Michael; Reinert, Andreas; Mai, Björn Erik; Kuznecov, Mihail

    A solid oxide fuel cell (SOFC) stack module is presented that is designed for operation on diesel reformate in an auxiliary power unit (APU). The stack was designed using a top-down approach, based on a specification of an APU system that is installed on board of vehicles. The stack design is planar, modular and scalable with stamped sheet metal interconnectors. It features thin membrane electrode assemblies (MEAs), such as electrolyte supported cells (ESC) and operates at elevated temperatures around 800 °C. The stack has a low pressure drop in both the anode and the cathode to facilitate a simple system layout. An overview of the technical targets met so far is given. A stack power density of 0.2 kW l -1 has been demonstrated in a fully integrated, thermally self-sustaining APU prototype running with diesel and without an external water supply.

  7. Research of auxiliary supporting means in swimming training of adults, which are afraid of water

    Directory of Open Access Journals (Sweden)

    Liliya Sheyko

    2015-02-01

    Full Text Available Purpose: to consider the possibility of effective teaching swimming adults suffering from hydrophobia, using auxiliary equipment. Materials and Methods: the study involved 37 people aged 22–45 years. Applied: analysis of the educational process of learning to swim, questioning, peer review techniques, teacher observation and experiment, mathematical statistics. Results: this study suggests that the formation of swimming skills is faster and more effective when used the auxiliary equipment. In the experimental group, four swimming styles were mastered by 59% and in the control by 18%. Conclusions: the proposed method of training of adults, with auxiliary equipment, allows to overcome the feelings of fear, accelerates the learning process and improve its efficiency.

  8. Treatment for chronic daily headache by using auxiliary and alternative methods

    Directory of Open Access Journals (Sweden)

    V. A. Golovacheva

    2015-01-01

    Full Text Available Chronic daily headache (CDH is one of the top 10 causes of adult disability and one of the 5 most common causes of female disability. To treat patients with CDH is one of the most difficult tasks in neurological practice. Difficulties in managing patients with CHD are associated with the high prevalence of comorbid mental disorders, analgesic abuse, pain syndromes at another site, and misconceptions of a patient about his/her disease. A combination of drug and non-drug therapies is the mainstay of the current approach to treating patients with CDH. Standard, alternative, and auxiliary therapies are identified. The paper describes different types of current auxiliary and alternative therapy used in the world’s leading headache centers and clinics. It describes experience with cerebrolysin used as auxiliary and alternative pharmacotherapies for CDH.

  9. MAP estimation for hyperspectral image resolution enhancement using an auxiliary sensor.

    Science.gov (United States)

    Hardie, Russell C; Eismann, Michael T; Wilson, Gregory L

    2004-09-01

    This paper presents a novel maximum a posteriori estimator for enhancing the spatial resolution of an image using co-registered high spatial-resolution imagery from an auxiliary sensor. Here, we focus on the use of high-resolution panchomatic data to enhance hyperspectral imagery. However, the estimation framework developed allows for any number of spectral bands in the primary and auxiliary image. The proposed technique is suitable for applications where some correlation, either localized or global, exists between the auxiliary image and the image being enhanced. To exploit localized correlations, a spatially varying statistical model, based on vector quantization, is used. Another important aspect of the proposed algorithm is that it allows for the use of an accurate observation model relating the "true" scene with the low-resolutions observations. Experimental results with hyperspectral data derived from the airborne visible-infrared imaging spectrometer are presented to demonstrate the efficacy of the proposed estimator.

  10. Auxiliary field Monte-Carlo study of the QCD phase diagram at strong coupling

    CERN Document Server

    Ohnishi, Akira; Nakano, Takashi Z

    2012-01-01

    We investigate the QCD phase diagram in the strong coupling limit by using a newly developed auxiliary field Monte-Carlo (AFMC) method. Starting from an effective action in the leading order of the 1/g^2 and 1/d expansion with one species of unrooted staggered fermion, we solve the many-body problem exactly by introducing the auxiliary fields and integrating out the temporal links and quark fields. We have a sign problem in AFMC, which is different from the original one in finite density lattice QCD. For low momentum auxiliary field modes, a complex phase cancellation mechanism exists, and the sign problem is not serious on a small lattice. Compared with the mean field results, the transition temperature is found to be reduced by around 10 % and the hadron phase is found to be extended in the larger chemical potential direction by around 20 %, as observed in the monomer-dimer-polymer (MDP) simulations.

  11. The PRHR Cooling Capacity during the Fail of Normal Feedwater Flow Accident for AP1000%AP1000丧失正常给水事故PRHR冷却能力研究

    Institute of Scientific and Technical Information of China (English)

    莫小锦; 佟立丽; 曹学武

    2012-01-01

    AP1000作为第三代革新型核电厂,广泛采用了非能动安全设计,来提高系统的安全性和经济性.其中,非能动余热排出系统(PRHR)用于应对正常余热排出路径失效的事故.本文采用机理性分析程序建立了包括主冷却剂系统(RCS)、专设安全设施(ESF)、以及简化的二回路系统的AP1000核电厂模型,对AP1000核电厂丧失正常给水事故进程进行了模拟计算.并且着重分析了非能动余热排出系统在丧失正常给水事故工况中的瞬态响应、热工水力行为及其冷却能力,并将PRHR与内置换料水箱(IRWST)的换热功率与堆芯衰变热功率进行了比较.研究表明,在丧失正常给水事故中,PRHR的热移出功率最终能够与堆芯的衰变功率相匹配,PRHR热交换器(PRHR HX)有能力带走衰变热,将反应堆主系统维持在安全停堆的状态.%AP1 000 is the third generation of innovation-typed nuclear power plant and widely adopts passive safety design to increase safety and efficiency. Particularly, a Passive Residual Heat Removal (PRHR) system is used to deal with the accident due to the failure of normal residual heat removal path. AP1000 plant model is established by using mechanism-based code. The plant model includes the Reactor Coolant System (RCS), Engineering Safety Features (ESFs), and part simplified second side system. And the fail of normal feedwater flow accident of AP1000 plant is selected to analyze the accident progression. The transient response, thermal-hydraulic phenomena, and the cooling capacity of the PRHR are focused on. The transfer heat power from PRHR to IRWST and reactor core decay power are compared with each other. The result shows that in the case of failure accident due to normal residual heat removal path, the removal heat power of PRHR Heat eXchanger (PRHR HX) is able to match with the reactor core decay power at the late stage of the accident, meets the requirements of sustainable long-term core cooling

  12. Operating the Gentilly-2 steam generating system without hydrazine

    International Nuclear Information System (INIS)

    The Gentilly-2 plant is a CANDU 600 operating in the province of Quebec. For the past two years the feedwater and steam generators have been operating with All Volatile Treatment using morpholine and have operated without hydrazine addition. This paper reviews the operating experience of the Gentilly 2 feedwater system and the steam generators. The Gentilly-2 steam and feedwater system has an all-ferrous feedtrain which includes a deaerator but has admiralty brass condenser tubes. The operating staff became concerned about decomposition of the hydrazine to ammonia and attack of ammonia on the condenser tubes. As a result of this the operating staff decided to halt hydrazine addition and to determine if the system experienced any problem due to the lack of hydrazine. After two years of operation the system continues to operate within the specified chemistry limits. In addition, inspection of the system shows that there has been no increased corrosion product transport and that the deaerator storage tank and the steam generators have not had any significant crud buildup. This experience indicates that an all-ferrous system may operate without hydrazine addition without experiencing deleterious effects. However, this does not imply that hydrazine addition is without benefit. The system performance will continue to be monitored and attempts will be made to determine whether the corrosion products being produced at Gentilly-2 are significantly different from other plants operating with hydrazine

  13. Auxiliary matrix formalism for interaction representation transformations, optimal control, and spin relaxation theories

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, D. L.; Kuprov, Ilya, E-mail: i.kuprov@soton.ac.uk [School of Chemistry, University of Southampton, Highfield Campus, Southampton SO17 1BJ (United Kingdom)

    2015-08-28

    Auxiliary matrix exponential method is used to derive simple and numerically efficient general expressions for the following, historically rather cumbersome, and hard to compute, theoretical methods: (1) average Hamiltonian theory following interaction representation transformations; (2) Bloch-Redfield-Wangsness theory of nuclear and electron relaxation; (3) gradient ascent pulse engineering version of quantum optimal control theory. In the context of spin dynamics, the auxiliary matrix exponential method is more efficient than methods based on matrix factorizations and also exhibits more favourable complexity scaling with the dimension of the Hamiltonian matrix.

  14. [Impact of directly compressed auxiliary materials on powder property of fermented cordyceps powder].

    Science.gov (United States)

    Chen, Li-Hua; Yue, Guo-Chao; Guan, Yong-Mei; Yang, Ming; Zhu, Wei-Feng

    2014-01-01

    To investigate such physical indexes as hygroscopicity, angle of repose, bulk density, fillibility of compression of mixed powder of directly compressed auxiliary materials and fermented cordyceps powder by using micromeritic study methods. The results showed that spray-dried lactose Flowlac100 and microcrystalline cellulose Avicel PH102 had better effect in liquidity and compressibility on fermented cordyceps powder than pregelatinized starch. The study on the impact of directly compressed auxiliary materials on the powder property of fermented cordyceps powder had guiding significant to the research of fermented cordyceps powder tablets, and could provide basis for the development of fermented cordyceps powder tablets. PMID:24754170

  15. Techno-economic analysis of fuel cell auxiliary power units as alternative to idling

    Science.gov (United States)

    Jain, Semant; Chen, Hsieh-Yeh; Schwank, Johannes

    This paper presents a techno-economic analysis of fuel-cell-based auxiliary power units (APUs), with emphasis on applications in the trucking industry and the military. The APU system is intended to reduce the need for discretionary idling of diesel engines or gas turbines. The analysis considers the options for on-board fuel processing of diesel and compares the two leading fuel cell contenders for automotive APU applications: proton exchange membrane fuel cell and solid oxide fuel cell. As options for on-board diesel reforming, partial oxidation and auto-thermal reforming are considered. Finally, using estimated and projected efficiency data, fuel consumption patterns, capital investment, and operating costs of fuel-cell APUs, an economic evaluation of diesel-based APUs is presented, with emphasis on break-even periods as a function of fuel cost, investment cost, idling time, and idling efficiency. The analysis shows that within the range of parameters studied, there are many conditions where deployment of an SOFC-based APU is economically viable. Our analysis indicates that at an APU system cost of 100 kW -1, the economic break-even period is within 1 year for almost the entire range of conditions. At 500 kW -1 investment cost, a 2-year break-even period is possible except for the lowest end of the fuel consumption range considered. However, if the APU investment cost is 3000 kW -1, break-even would only be possible at the highest fuel consumption scenarios. For Abram tanks, even at typical land delivered fuel costs, a 2-year break-even period is possible for APU investment costs as high as 1100 kW -1.

  16. Impact of component unavailability uncertainty on safety systems unavailability

    International Nuclear Information System (INIS)

    Highlights: • Impact of component unavailability uncertainty on systems unavailability is analyzed. • Analysis is done with Monte Carlo sampling and min cut upper bound approximation. • The top event uncertainty depends on the basic events unavailability distribution. • The top event uncertainty depends on the importance of the basic events. • Introduction of lognormal distribution results in increased top event uncertainty. - Abstract: The increased and extended application of the probabilistic safety assessment requires appropriate consideration of uncertainties in the analyses and interpretation of the results. Inadequate treatment of uncertainties may lead to poorly supported or even wrong conclusions with final consequence of loss of adequate level of safety. Epistemic uncertainty results from the imperfect knowledge or incomplete information regarding the parameters values in the underlying model. Epistemic uncertainty is considered in the probabilistic safety assessment models by probability distributions associated with the uncertain parameters. This paper presents the results of the analysis of the introduction of probability distributions associated with component unavailability parameters, on the overall unavailability of the analyzed system. The normal and lognormal distributions are introduced as probability distributions associated with component unavailability. The minimal cut sets of the analyzed system are identified with application of the fault tree analysis. The distribution of the top event unavailability is assessed with application of the min cut upper bound approximation and Monte Carlo sampling. The analysis of the uncertainty propagation is demonstrated using the fault tree of the auxiliary feedwater system of the nuclear power plant. The implications of the introduction of different probability distributions for the components unavailability on the obtained results are analyzed. Obtained results include skewness and kurtosis as

  17. Lubrication System with Tolerance for Reduced Gravity

    Science.gov (United States)

    Portlock, Lawrence E. (Inventor); McCune, Michael E. (Inventor); Dobek, Louis J. (Inventor)

    2013-01-01

    A lubrication system includes an auxiliary lubricant tank 48, a supply conduit 58 extending from a source of lubricant 26 to the auxiliary lubricant tank. A reduced-G bypass line 108 branches from the conduit and enters the auxiliary tank at a first elevation E.sub.1. The system also includes an auxiliary tank discharge conduit 116, a portion of which resides within the tank. The resident portion has an opening 122 at least partially at a second elevation E.sub.2 higher than the first elevation.

  18. Active fault detection in MIMO systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2014-01-01

    The focus in this paper is on active fault detection (AFD) for MIMO systems with parametric faults. The problem of design of auxiliary inputs with respect to detection of parametric faults is investigated. An analysis of the design of auxiliary inputs is given based on analytic transfer functions...... from auxiliary input to residual outputs. The analysis is based on a singular value decomposition of these transfer functions Based on this analysis, it is possible to design auxiliary input as well as design of the associated residual vector with respect to every single parametric fault in the system...

  19. RELAP5/MOD3 code manual: Code structure, system models, and solution methods. Volume 1

    International Nuclear Information System (INIS)

    The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling, approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I provides modeling theory and associated numerical schemes

  20. RELAP5/MOD3 code manual: Code structure, system models, and solution methods. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling, approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I provides modeling theory and associated numerical schemes.

  1. Refrigeration engineering 3. Components, working fluids and auxiliary fluids. Standards; Kaeltetechnik 3. Bauteile, Betriebs- und Hilfsstoffe. Normen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    Standards and standardisation support economy and society in strengthening, designing and developing regional and global markets; standardisation removes technical obstacles to trading and improves the competitive strength of industrial organisations. Since 1945, the Normenausschuss Kaeltetechnik (German Refrigeration Engineering Standardisation Committee) has been working on national, European and international standards. The DIN catalogue of rules currently comprises about 120 standards and draft standards. During the past few years, many new refrigeration standards have emerged on a national, European and international scale. In order to take account of this development and to provide a handy reference manual for daily use, the new DIN pocket book of refrigeration engineering comprises the tree sections: 1. Safety and environmental protection; 2. Refrigeration systems and motor car cooling; 3. Components, working fluids, auxiliary fluids. This is Vol. 3, which contains relevant standards of flanges, circuit components, refrigerating oils, compressors, etc. (orig.)

  2. Auxiliary energy in building technical services - Potential for savings and ways toward implementation; Hilfsenergie Haustechnik: Einspar-Potenziale und Umsetzungspfade

    Energy Technology Data Exchange (ETDEWEB)

    Nipkow, J. [Schweizerische Agentur fuer Energieeffizienz (SAFE), Zuerich (Switzerland); Peters, M.; Wapf, B. [Econcept AG, Zuerich (Switzerland)

    2006-11-15

    This report for the Swiss Federal Office of Energy (SFOE) examines the potential available for saving energy in the building technical services area. Savings of six to eight percent are noted for the area concerning pumps, fans, control systems, etc. The report presents the aims of the project and reviews the definition of auxiliary energy. National and international energy labels, limiting values and typical values for efficiency are examined. The results of surveys are presented and discussed as are the opinions and suggestions of planners, installers and architects. Manufacturers' opinions and marketing aspects are briefly examined, as are energy labels and regulations. Implementation of measures in various areas are described. Economical aspects and actions to be taken are discussed and educational measures are looked at. Follow-up projects are defined.

  3. Research and Design of Power Information Network Risk Assessment Auxiliary System Abstract:This paper designed a multi-expert assessmem system,which runs in strict accordance with the"Guide"to assess the risk assessment process,making assessment resu...%电力信息网风险评估辅助系统的研究与设计

    Institute of Scientific and Technical Information of China (English)

    杨大威; 刘宇

    2011-01-01

    This paper designed a multi-expert assessmem system,which runs in strict accordance with the"Guide"to assess the risk assessment process,making assessment results more comprehensive and objective.%本文设计的信息安全风险评估辅助系统是一个多专家评估系统,主要模块分为风险评估管理端、系统评估端、信息库管理端和知识库管理端,严格按照《指南》的风险评估流程进行评估,使评估结果更全面更客观。

  4. Non-cross-linked polystyrene-supported 2-imidazolidinone chiral auxiliary: synthesis and application in asymmetric alkylation reactions

    Science.gov (United States)

    Nguyen, Quynh Pham Bao

    2013-01-01

    Summary Asymmetric alkylation reactions using non-cross-linked polystyrene (NCPS)-supported 2-imidazolidinone chiral auxiliaries were successfully investigated with excellent diastereocontrol (>99% de). The recovery and the recycling of this soluble polymer-supported chiral auxiliary were achieved in order to produce highly optical pure carboxylic acids. PMID:24204423

  5. Acylation, Diastereoselective Alkylation, and Cleavage of an Oxazolidinone Chiral Auxiliary: A Multistep Asymmetric Synthesis Experiment for Advanced Undergraduates

    Science.gov (United States)

    Smith, Thomas E.; Richardson, David P.; Truran, George A.; Belecki, Katherine; Onishi, Megumi

    2008-01-01

    An introduction to the concepts and experimental techniques of diastereoselective synthesis using a chiral auxiliary is described. The 4-benzyl-2-oxazolidinone chiral auxiliary developed by Evans is acylated with propionic anhydride under mild conditions using DMAP as an acyl transfer catalyst. Deprotonation with NaN(TMS)[subscript 2] at -78…

  6. Installation package for a domestic solar heating and hot water system

    Science.gov (United States)

    1978-01-01

    The installation of two prototype solar heating and hot water systems is described. The systems consists of the following subsystems: solar collector, storage, control, transport, and auxiliary energy.

  7. New materials for auxiliary equipments manufacturing. Nuevos materiales para la construccion de bienes de equipo

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Zayas, J. (Dto. Ingenieria Quimica y Metalurgia. Universidad de Barcelona (Spain))

    1993-07-01

    Some specific operational conditions at industrial chemical processes might oblige the conventional materials used for auxiliary equipments to be substituted by new materials like new steel alloys, non-ferrous metals, ceramics, composites, etc.. This article studies the characteristics, applications and types of new materials. (Author)

  8. Application of the Method of Auxiliary Sources for the Analysis of Electromagnetic Scattering by Impedance Spheres

    DEFF Research Database (Denmark)

    Karamehmedovic, Mirza; Breinbjerg, Olav

    2002-01-01

    The Method of Auxiliary Sources (MAS) is applied to 3D scattering problems involving spherical impedance scatterers. The MAS results are compared with the reference spherical wave expansion (SWE) solution. It is demonstrated that good agreement is achieved between the MAS and SWE results....

  9. C1 compounds as auxiliary substrate for engineered Pseudomonas putida S12

    NARCIS (Netherlands)

    Koopman, F.W.; De Winde, J.H.; Ruijssenaars, H.J.

    2009-01-01

    The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to efficiently utilize the C1 compounds methanol and formaldehyde as auxiliary substrate. The hps and phi genes of Bacillus brevis, encoding two key steps of the ribulose monophosphate (RuMP) pathway, were introduced to construct a

  10. Kindergarten Mathematics with "Pepe the Rabbit": How Kindergartners Use Auxiliary Means to Solve Problems

    Science.gov (United States)

    Skoumpourdi, Chrysanthi

    2010-01-01

    The aim of this paper is to investigate the role that auxiliary means (manipulatives such as cubes and representations such as number line) play for kindergartners in working out mathematical tasks. Our assumption was that manipulatives such as cubes would be used by kindergartners easily and successfully whereas the number line would be used by…

  11. From Root Infinitive to Finite Sentence : The acquisition of verbal inflections and auxiliaries

    NARCIS (Netherlands)

    Blom, W.B.T.

    2003-01-01

    Across languages, children in the earliest stages of syntactic development tend to omit overt markings of finiteness, such as verbal inflections and auxiliaries: when children use a verb, they use an infinitival form (e.g. Dutch) or a bare stem (e.g. English). From Root Infinitive to Finite Sentence

  12. Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit

    OpenAIRE

    Dudrik, Jaroslav; BODOR Marcel; TRIP Daniel Nistor

    2010-01-01

    Auxiliary circuit for DC/DC converter withcontrolled output rectifier is presented in this paper.Soft switching for power switches of the inverter isachieved by using controlled output rectifier and softswitching of the controlled rectifier by using losslessauxiliary circuit. The principle of converter operationis explained and analyzed and experimental results onthe laboratory model are presented.

  13. Application of the method of auxiliary sources in optical diffraction microscopy

    DEFF Research Database (Denmark)

    Karamehmedovic, Mirza; Sørensen, Mads Peter; Hansen, Poul-Erik;

    2010-01-01

    The Method of Auxiliary Sources is used for characterisation of grating defects. Grating profiles are characterised by best fit matching of a library of diffraction efficiencies with numerical simulated diffraction efficiencies with defects. It is shown that the presented method can solve...

  14. Auxiliary Women Workers in the Legal Sector: Traversing Subjectivities and "Self" to Learn through Work

    Science.gov (United States)

    Cavanagh, Jillian Maria

    2012-01-01

    This study is about female auxiliary workers in the Australian legal sector. The purpose is to explore the impact of subjectivities on women workers and how they negotiate their positionality to participate in meaningful work and learning. The study is grounded in theories of identity and socio-cultural perspectives of subjectivity, agentic action…

  15. Are Modal Auxiliaries in Malaysian English Language Textbooks in Line with Their Usage in Real Language?

    Science.gov (United States)

    Khojasteh, Laleh; Kafipour, Reza

    2012-01-01

    Based on the discrepancies found in many Malaysian English language textbooks, a detailed analysis on the way modal auxiliary verb forms and their semantic functions were introduced and presented in texts and exercises in five Malaysian textbooks was done. For that to be achieved, a qualitative page-by-page content analysis was applied. From the…

  16. Exact solutions of some coupled nonlinear diffusion-reaction equations using auxiliary equation method

    Indian Academy of Sciences (India)

    Ranjit Kumar

    2012-09-01

    Travelling and solitary wave solutions of certain coupled nonlinear diffusion-reaction equations have been constructed using the auxiliary equation method. These equations arise in a variety of contexts not only in biological, chemical and physical sciences but also in ecological and social sciences.

  17. Equivalence Between Different Auxiliary Field Formulations of ${\\cal N}=1$ Supergravity Coupled to Matter

    CERN Document Server

    Aoki, Shuntaro

    2016-01-01

    We reconsider the relation between three supergravity formalisms with different sets of auxiliary fields, known as the old-, new-, and non-minimal supergravity. Although it has been known that the old minimal formulation is the broadest class, we find that, with an unphysical $U(1)$ gauge symmetry and a compensating superfield, all of them become completely equivalent.

  18. 49 CFR 393.24 - Requirements for head lamps, auxiliary driving lamps and front fog lamps.

    Science.gov (United States)

    2010-10-01

    ... Devices, and Electrical Wiring § 393.24 Requirements for head lamps, auxiliary driving lamps and front fog lamps. (a) Headlamps. Every bus, truck and truck tractor shall be equipped with headlamps as required by... specifications in FMVSS No. 108 (49 CFR 571.108), SAE J581, and SAE J583, respectively....

  19. Asymmetric synthesis of 3-butylphthalide using isomannide and isosorbide as chiral auxiliaries

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new approach for asymmetric syntheses of (S) and (R)-3-n-butylphthalide (NBP) is presented. The diastereoselective addition of dibutylzinic to aromatic aldehyde 10 or 11 generated from isomannide- or isosorbide-derived chiral auxiliary afforded S-NBP or R-NBP in high optical yields.

  20. Efficient calculation of nuclear spin-rotation constants from auxiliary density functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Zuniga-Gutierrez, Bernardo, E-mail: bzuniga.51@gmail.com [Departamento de Ciencias Computacionales, Universidad de Guadalajara, Blvd. Marcelino García Barragán 1421, C.P. 44430 Guadalajara, Jalisco (Mexico); Camacho-Gonzalez, Monica [Universidad Tecnológica de Tecámac, División A2, Procesos Industriales, Carretera Federal México Pachuca Km 37.5, Col. Sierra Hermosa, C.P. 55740 Tecámac, Estado de México (Mexico); Bendana-Castillo, Alfonso [Universidad Tecnológica de Tecámac, División A3, Tecnologías de la Información y Comunicaciones, Carretera Federal México Pachuca Km 37.5, Col. Sierra Hermosa, C.P. 55740 Tecámac, Estado de México (Mexico); Simon-Bastida, Patricia [Universidad Tecnlógica de Tulancingo, División Electromecánica, Camino a Ahuehuetitla No. 301, Col. Las Presas, C.P. 43642 Tulancingo, Hidalgo (Mexico); Calaminici, Patrizia; Köster, Andreas M. [Departamento de Química, CINVESTAV, Avenida Instituto Politécnico Nacional 2508, A.P. 14-740, México D.F. 07000 (Mexico)

    2015-09-14

    The computation of the spin-rotation tensor within the framework of auxiliary density functional theory (ADFT) in combination with the gauge including atomic orbital (GIAO) scheme, to treat the gauge origin problem, is presented. For the spin-rotation tensor, the calculation of the magnetic shielding tensor represents the most demanding computational task. Employing the ADFT-GIAO methodology, the central processing unit time for the magnetic shielding tensor calculation can be dramatically reduced. In this work, the quality of spin-rotation constants obtained with the ADFT-GIAO methodology is compared with available experimental data as well as with other theoretical results at the Hartree-Fock and coupled-cluster level of theory. It is found that the agreement between the ADFT-GIAO results and the experiment is good and very similar to the ones obtained by the coupled-cluster single-doubles-perturbative triples-GIAO methodology. With the improved computational performance achieved, the computation of the spin-rotation tensors of large systems or along Born-Oppenheimer molecular dynamics trajectories becomes feasible in reasonable times. Three models of carbon fullerenes containing hundreds of atoms and thousands of basis functions are used for benchmarking the performance. Furthermore, a theoretical study of temperature effects on the structure and spin-rotation tensor of the H{sup 12}C–{sup 12}CH–DF complex is presented. Here, the temperature dependency of the spin-rotation tensor of the fluorine nucleus can be used to identify experimentally the so far unknown bent isomer of this complex. To the best of our knowledge this is the first time that temperature effects on the spin-rotation tensor are investigated.

  1. Inside-pipe hydrophobic coating method promoting dropwise condensation in a passive cooling system

    International Nuclear Information System (INIS)

    Submerged by large tsunami, active cooling system was not operated to cool down decay heat. Likewise, station black out can lead to severe accident so that the necessity of cooling system without requesting any electric power was stressed out. Passive Auxiliary Feedwater System(PAFS) is one of the passive cooling systems suggested by Korea Atomic Energy Research Institute(KAERI). It has hundreds of slightly inclined horizontal U-shaped pipes submerged in a large water pool. Under the accident circumstances, this system cools steam that comes from the steam generator into condensed water inside the pipes without any electric power. These pipes are made of stainless steel 304L, with the diameter of 50 mm, and the length of 8 m. The main heat transfer phenomenon inside a pipe is the condensation phenomenon. There are two modes of condensation: one is filmwise condensation(FWC) and the other is dropwise condensation(DWC). On a surface wetted by a liquid well, FWC occurs to form liquid film. The final goal of this study is to increase cooling capacity of passive safety system like PAFS. Up to now, the attempts to increase condensation heat transfer were limited to make finned tube. DWC which has higher heat transfer coefficient was only promoted on vertical plates or external pipes. By promoting DWC inside a pipe, condensation heat transfer will be fundamentally enhanced. In this paper, hydrophobic coating inside a pipe method will be presented for promoting DWC, and its condensation heat transfer performance will be evaluated by conducting condensation experiment on a vertical plate. The inside-pipe hydrophobic coating method was developed using Teflon, and it was checked that DWC was promoted by this method with visualization results. At the saturation pressure of 145kPa, average heat transfer coefficient for DWC was 53.3 kW/m''2/K, and that for FWC was 13.5 kW/m''2/K. Based on this results, it can be concluded that this coating method will

  2. Inside-pipe hydrophobic coating method promoting dropwise condensation in a passive cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Joo Won; Kang, Jun Young; Hwang, Kyoung Won; Park, Hyun Sun; Kiyofumi, Moriyama [POSTECH, Pohang(Korea, Republic of); Kim, Moo Hwan [Korea Institute of nuclear safety, Daejeon(Korea, Republic of)

    2015-05-15

    Submerged by large tsunami, active cooling system was not operated to cool down decay heat. Likewise, station black out can lead to severe accident so that the necessity of cooling system without requesting any electric power was stressed out. Passive Auxiliary Feedwater System(PAFS) is one of the passive cooling systems suggested by Korea Atomic Energy Research Institute(KAERI). It has hundreds of slightly inclined horizontal U-shaped pipes submerged in a large water pool. Under the accident circumstances, this system cools steam that comes from the steam generator into condensed water inside the pipes without any electric power. These pipes are made of stainless steel 304L, with the diameter of 50 mm, and the length of 8 m. The main heat transfer phenomenon inside a pipe is the condensation phenomenon. There are two modes of condensation: one is filmwise condensation(FWC) and the other is dropwise condensation(DWC). On a surface wetted by a liquid well, FWC occurs to form liquid film. The final goal of this study is to increase cooling capacity of passive safety system like PAFS. Up to now, the attempts to increase condensation heat transfer were limited to make finned tube. DWC which has higher heat transfer coefficient was only promoted on vertical plates or external pipes. By promoting DWC inside a pipe, condensation heat transfer will be fundamentally enhanced. In this paper, hydrophobic coating inside a pipe method will be presented for promoting DWC, and its condensation heat transfer performance will be evaluated by conducting condensation experiment on a vertical plate. The inside-pipe hydrophobic coating method was developed using Teflon, and it was checked that DWC was promoted by this method with visualization results. At the saturation pressure of 145kPa, average heat transfer coefficient for DWC was 53.3 kW/m''2/K, and that for FWC was 13.5 kW/m''2/K. Based on this results, it can be concluded that this coating method will

  3. Geometric descriptions of entangled states by auxiliary varieties

    International Nuclear Information System (INIS)

    The aim of the paper is to propose geometric descriptions of multipartite entangled states using algebraic geometry. In the context of this paper, geometric means each stratum of the Hilbert space, corresponding to an entangled state, is an open subset of an algebraic variety built by classical geometric constructions (tangent lines, secant lines) from the set of separable states. In this setting, we describe well-known classifications of multipartite entanglement such as 2 × 2 × (n+ 1), for n⩾ 1, quantum systems and a new description with the 2 × 3 × 3 quantum system. Our results complete the approach of Miyake and make stronger connections with recent work of algebraic geometers. Moreover, for the quantum systems detailed in this paper, we propose an algorithm, based on the classical theory of invariants, to decide to which subvariety of the Hilbert space a given state belongs.

  4. Adaptive cancellation of Es layer interference using auxiliary horizontal antennas

    Institute of Scientific and Technical Information of China (English)

    Zhao Long; Zhang Ning

    2006-01-01

    Based on a dual-polarization high-frequency wave radar system, an adaptive system using horizontal antennas for the suppression of the Es layer interference (ELI) is described. The data received from the horizontal antennas were correlated with the data received from the Vertically Polarized Antennas (VPAs) to estimate and cancel the interference adaptively in the VPAs. Suppressing the interference after each coherent integration time interval, about 25 dB signal-to-interference ratio is expected with the experimentally derived data.

  5. 机组冷态启动中几种投运方案经济性分析%Economic analysis on several operation schemes for steam-driven feedwater pump group during unit cold starting

    Institute of Scientific and Technical Information of China (English)

    朱慧强

    2014-01-01

    By taking a subcritical 350 MW unit in Huaneng Dandong Power Plant as an example,the opera-tion schemes of the steam-driven feedwater pump group of which the booster pump and small steam turbine are driven coaxially were investigated.Moreover,the calculated economy of three schemes was compared. The results show that,the Scheme III has the optimum economy and safety,in which the motor-driven feedwater pumps were adopted during water feeding,boiler washing and furnace temperature enhancing un-til the steam turbine speed increases to 2 900 r/min in the initial stage of unit cold state startup,then the first steam-driven feedwater pump was put into service when the unit load reached 30%.Therefore,not all units are fitted for using steam-driven turbine to accomplish cold state startup.The reasonable startup schemes should be proposed by considering the actual situation of each unit comprehensively.%以华能丹东电厂亚临界350 MW机组为例,针对前置泵与小汽轮机同轴驱动的汽动给水泵(汽泵)组在机组冷态启动中的投运方式进行分析,并对3种投运方案的经济性进行了计算比较。结果表明:机组冷态启机初期锅炉上水、锅炉冲洗及提高锅炉温度至汽轮机转速达到2900 r/min暖机期间均采用电动给水泵(电泵),之后投入第1台汽泵至机组负荷达到30%的方案3经济性和安全性最佳。因此,并非所有机组的冷态启动均适用汽泵启动,而应综合考虑各机组的实际情况,提出合理的启动方案。

  6. 辅助根管冲洗器械的研究新进展%Advances in auxiliary root canal irrigation instrument

    Institute of Scientific and Technical Information of China (English)

    吴丽更; 穆颖

    2012-01-01

    Root canal irrigation is a must in root canal therapy, however,not a irrigating solution or a com-bination of some irrigating solutions can completely remove the smear layer. Consequently, auxiliary root canal irrigation instrument arises to improve the cleaning efficiency of root canal system . This article reviews four kinds of auxiliary root canal irrigation instruments, namely, the manual irrigation system, pressure switch system, acoustic system and ul-trasonic system.%目前尚未发现一种冲洗液或多种冲洗液的联合应用能够彻底清除根管玷污层.因此,各种辅助根管冲洗器械应运而生,以提高根管系统的清洁率.本文就各种辅助根管冲洗器械如:手动冲洗系统、压力转换系统、声波系统、超声波系统作一综述.

  7. Excited state calculations using phaseless auxiliary-field quantum Monte Carlo: potential energy curves of low lying C2 singlet states

    OpenAIRE

    Purwanto, Wirawan; Zhang, Shiwei; Krakauer, Henry

    2008-01-01

    We show that the recently developed phaseless auxiliary-field quantum Monte Carlo (AFQMC) method can be used to study excited states, providing an alternative to standard quantum chemistry methods. The phaseless AFQMC approach, whose computational cost scales as M^3-M^4 with system size M, has been shown to be among the most accurate many-body methods in ground state calculations. For excited states, prevention of collapse into the ground state and control of the Fermion sign/phase problem ar...

  8. Auxiliaries for the textile industry and environmental protection

    Directory of Open Access Journals (Sweden)

    Sanda VISAN

    2010-06-01

    Full Text Available The textile industry is an industrial field that affects the environment, from the plant growth until the production process. The obtaining of environmental licence for Romanian companies that produce textile products is related to elaboration and implementation of a modern system for an environmental management, that consist in utilization of ecological technologies for finishing, in diminution the water and energy consumption, cleaning of waste waters, reutilization of cleaned waters, sustainable management of wastes. In this study, the surfactant categories used in the textile industry that fulfil the conditions of environment protection, are presented. Some exemplifications were made involving the existing surfactants in Romanian textile industry, obtained from both domestic and external production. Also, some recommendation are suggested regarding the utilization of surfactants manufactured from either vegetal oils or chemical/petrochemical wastes, with similar properties as those from import having decreased prices an that affect as small as possible the environment.

  9. Relativistic wave equations for fermions; auxiliary-spin content; simple equations; theorems about spin 3/2

    Energy Technology Data Exchange (ETDEWEB)

    Labonte, G. (Freie Univ. Berlin (Germany, F.R.). Inst. fuer Theoretische Physik; Royal Military Coll. of Canada, Kingston, Ontario. Dept. of Mathematics and Computer Science)

    1983-06-21

    The properties of the GAMMA-matrices for general fermion equations are analysed with respect to the auxiliary-spin content. Equations are derived for the submatrices interconnecting the different spin components, in a basis in which the generators of SU/sub 2/ are fully reduced. The family of equations in which the physical spin s is not also an auxiliary spin is pointed out as being particularly simple. Theorems are proved concerning this family: they can involve only spins smaller than s; there is only one auxiliary spin, if and only if s=3/2; when the Harish-Chandra degree is four, s=3/2.

  10. Ghostbusters in higher derivative supersymmetric theories: who is afraid of propagating auxiliary fields?

    CERN Document Server

    Fujimori, Toshiaki; Yamada, Yusuke

    2016-01-01

    We present for the first time a ghost-free higher-derivative chiral model with a propagating auxiliary F-term field (highest component of the chiral multiplet). We obtain this model by removing a ghost in a higher derivative chiral model, with Higgsing it in terms of an auxiliary vector superfield. Depending on the sign of the quadratic derivative term of the chiral superfield, the model contains two ghost free branches of the parameter regions. We find that supersymmetry is spontaneously broken in one branch while it is preserved in the other branch. As a consequence of dynamical F-term field, a conserved U(1) charge corresponding to the number density of $F$ appears, which can be regarded as a generalization of the R-symmetry.

  11. Reexamination of molecular integrals arising from the Dirac equation. Analytical evaluation of molecular auxiliary functions integrals

    CERN Document Server

    Bagci, A

    2016-01-01

    The author in his previous works were presented a numerical integration method, namely, global-adaptive with the Gauss-Kronrod numerical integration extension in order to accurate calculation of molecular auxiliary functions integrals involve power functions with non-integer exponents. They are constitute elements of molecular integrals arising in Dirac equation when Slater-type orbitals with non-integer principal quantum numbers are used. Binomial series representation of power functions method, so far, is used for analytical evaluation of the molecular auxiliary function integrals however, intervals of integration cover areas beyond the condition of convergence. In the present study, analytical evaluation of these integrals is re-examined. They are expressed via prolate spheroidal coordinates. An alternative analytical approximation are derived. Slowly convergent binomial series representation formulae for power functions is investigated through nonlinear sequence transformations for the acceleration of con...

  12. Auxiliary particle filter-model predictive control of the vacuum arc remelting process

    Science.gov (United States)

    Lopez, F.; Beaman, J.; Williamson, R.

    2016-07-01

    Solidification control is required for the suppression of segregation defects in vacuum arc remelting of superalloys. In recent years, process controllers for the VAR process have been proposed based on linear models, which are known to be inaccurate in highly-dynamic conditions, e.g. start-up, hot-top and melt rate perturbations. A novel controller is proposed using auxiliary particle filter-model predictive control based on a nonlinear stochastic model. The auxiliary particle filter approximates the probability of the state, which is fed to a model predictive controller that returns an optimal control signal. For simplicity, the estimation and control problems are solved using Sequential Monte Carlo (SMC) methods. The validity of this approach is verified for a 430 mm (17 in) diameter Alloy 718 electrode melted into a 510 mm (20 in) diameter ingot. Simulation shows a more accurate and smoother performance than the one obtained with an earlier version of the controller.

  13. Postoperative imaging findings in children with auxiliary partial orthotopic liver transplant (APOLT).

    Science.gov (United States)

    Ayyala, Rama S; Martinez, Mercedes; Lobritto, Steven J; Kato, Tomoaki; Ruzal-Shapiro, Carrie

    2016-07-01

    Auxiliary partial orthotopic liver transplant (APOLT) is a treatment technique for people who have acute hepatic failure secondary to fulminant hepatic failure and might ultimately recover normal liver function. This surgical procedure is complicated, involving the placement of a liver graft while maintaining viability of the remaining native portion of the liver. This method allows the native liver to recover hepatic function, therefore eliminating the need for long-term immunosuppression, as is typically needed in post-transplant settings. Postoperative imaging in these cases can be challenging given the complex anatomy, specifically the vascular anastomosis. Therefore it is important for radiologists and clinicians to be aware of the anatomy as well as the variable imaging appearances of the liver. We review the imaging findings in children who have undergone auxiliary partial orthotopic liver transplant (APOLT). PMID:26867605

  14. Simulation of Multi output Fly back Converter with Integrated Auxiliary Buck Converter with reduced components

    Directory of Open Access Journals (Sweden)

    J.KOMATHI

    2015-04-01

    Full Text Available The fly back converter has been widely used for multi outputs due to the simple structure and low cost in low-power applications. This paper presents a new multi output converter. It consists of a half-bridge inverter with boost converter in primary side and a fly back rectifier that is integrated with an auxiliary buck converter in secondary side. The boost converter is used to generate high voltage dc from Low voltage PV cells. The primary switches control the main output voltage and the secondary synchronous switches control the auxiliary output voltage. The main advantages of the proposed converter are that the transformer size can be reduced due to the less magnetizing offset current, all the power switches including synchronous ones can achieve the zero-voltage switching (ZVS and it has no output cross regulation problems. The circuit is simulated using MATLAB. The performance is verified with simulation results.

  15. Study on the distribution of strata rock temperature around a driving head with auxiliary ventilation

    Institute of Scientific and Technical Information of China (English)

    GAO Jian-liang

    2004-01-01

    The distributions of strata rock temperature around a driving head with auxiliary ventilation were analyzed theoretically based on a program which was developed by the authors to predict the thermal environmental conditions in a development heading with forcing auxiliary ventilation. The influences of wetnessof the airway surface were discussed on the cooled zone of the strata rock and on the temperature distribution in the surrounding rock. It is shown that the advancing speed and driving time have little influence on the temperature profile in front of the working face of a driving airway, and the rock temperature 1.5 m ahead of the working face can be taken as the virgin rock temperature.

  16. Study on Commercial Application of FCC with Auxiliary Gasoline Reactor for Improving FCC Naphtha Quality

    Institute of Scientific and Technical Information of China (English)

    Wei Qiang

    2007-01-01

    This article introduces the commercial application of FCC technology equipped with a gasoline auxiliary reactor in the RFCC unit at PetroChina Harbin Petrochemical Branch Company.Test results have shown the excellent outcome for commercial application of the gasoline upgrading in the auxiliary reactor to reduce the olefin content in FCC naphtha.Application of this technology can reduce the olefin content in FCC naphtha to less than 35v%.Adjustment of the FCC operation towards more severg conditions can further reduce the olefin content in FCC naphtha to less than 20 v%.so that the FCC naphtha can meet the current standard or meet more stringent specification requirements in the future to achieve compelling economic and social benefits.

  17. 小型贯流锅炉给水处理中的反渗透技术应用%Application of Reverse Osmosis Technology in Feedwater Treatment for Small Tubular Boiler

    Institute of Scientific and Technical Information of China (English)

    贾旭亮; 杨洪东

    2012-01-01

    THe cost of ion exchange water, treatment for small tubular boiler feedwater is about 2.83 RMB/t. Compared with ion exchange water treatment process, the cost of reverse osmosis water treatment is about 5.04 RMB/t. However, the hardness, alkalinity and conductivity of reverse osmosis water is lower than that of ion exchange water, the boiler's continuous water volume of blowdown and discharge are reduced, which saves a lot of fuel. The results show that reverse osmosis water treatment process for boiler feedwater has more superiority in economy with simple operation and wide application prospect.%小型贯流锅炉具有效率高、节能、自动化程度高的特点,但对于给水水质要求也较高.与离子交换法相比,反渗透制水用于小型贯流锅炉给水时制水成本约5.04元/t,而离子交换的制水成本约2.83元/t,但反渗透的产水硬度、碱度、电导率都较离子交换水低,使锅炉的连续排污量和全排污量降低,从而节省了大量燃料费用,符合节能减排的要求.结果表明反渗透制水用于锅炉给水时,比离子交换制水更经济、操作更简单,应用前景广阔.

  18. A dimensão política do processo de formação de pessoal auxiliar: a enfermagem rumo ao SUS La dimensión política del proceso de formación del personal auxiliar: la enfermeria rumbo al SUS (Sistema Único de Salud The political dimension of auxiliary personnel education: nursing and the Unified Health System (SUS

    Directory of Open Access Journals (Sweden)

    Alva Helena de Almeida

    2002-10-01

    aprehendieron la dimensión técnica del proceso, aislada de la política.The change in the administration of the municipality of São Paulo in 1989 innovated the management of health services aiming at implementing the Unified Health System (SUS and using as a fundamental strategy the workers' qualification. Thus, the purpose of this work was to analyze the incorporation of the SUS principles in the programs for the capacitation of nursing auxiliary personnel. Based on the concepts that nurtured the Sanitary Reform and the construction of SUS principles, the methodological framework comprehended interviews with the coordinators of the program. Data analysis enabled authors to recognize that the municipal management policies and practices were committed to SUS guidelines, giving priority to the qualification of health workers who did not have this opportunity and adopting a pedagogy directed to the agents' transformation. The coordinators were motivated to develop the qualification program, recognizing this process as a tool for the SUS implementation. In addition, the coordinators at the regional level understood the technical dimension of this process, isolated from its political dimension.

  19. Thermal-hydraulic evaluation of passive containment cooling system of improved APR+ during LOCAs

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Byong Guk; NO, Hee Cheon, E-mail: hcno@kaist.ac.kr

    2014-10-15

    Highlights: • Larger air holdup tanks are confirmed to be needed for PCCS through MARS simulation. • Condensation model in MARS gives lower heat transfer than Dehbi's correlation. • Heat transfer resistance of steam–air mixture is dominant for PCCS tubes. • Heat sink structures remove dominant amount of decay heat initially. • Flow instability is eased at higher tube inlet form loss, return level, and angle. - Abstract: Various reactor concepts and technologies have been devised and evaluated to ensure the integrity of the core and the containment under a prolonged station blackout. After the successful validation of the passive auxiliary feedwater system (PAFS) of Advanced Power Reactor Plus (APR+), Korea is considering an improved APR+ with a passive containment cooling system (PCCS). In a previous paper, we suggested a PCCS design based on APR+ and performed a scoping analysis. We performed a MARS simulation for the thermal hydraulic evaluation of the system behavior, including natural circulation through the Passive Condensation Cooling Tank (PCCT) water pool and inside PCCS tubes as well as steam–air mixture condensation inside the containment. Through a simulation using the MARS system code, we investigated the effect of air holdup tanks (AHTs) on reduction of the air fraction in the containment, the effects of several steam–air mixture condensation models, the role of heat structures, and the flow instability inside the PCCS tubes. We found that the presence of AHT reduced the number of required PCCS tubes by more than half and the heat resistance of the steam–air mixture side is dominant in terms of governing the overall performance of PCCS. The embedded MARS condensation model and Uchida's correlation gave lower heat transfer coefficients than Dehbi's correlation, and heat structures removed more decay heat than PCCS tubes. Finally, intense flow instability inside the PCCS tubes was observed and was mitigated by placing

  20. Think Different: Applying the Old Macintosh Mantra to the Computability of the SUSY Auxiliary Field Problem

    CERN Document Server

    Calkins, Mathew; Gates,, S James; Golding, William M

    2015-01-01

    Starting with valise supermultiplets obtained from 0-branes plus field redefinitions, valise adinkra networks, and the "Garden Algebra," we discuss an architecture for algorithms that (starting from on-shell theories and, through a well-defined computation procedure), search for off-shell completions. We show in one dimension how to directly attack the notorious "off-shell auxiliary field" problem of supersymmetry with algorithms in the adinkra network-world formulation.