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Sample records for cathodic protection system

  1. Smart cathodic protection systems

    NARCIS (Netherlands)

    Polder, R.B.; Leggedoor, J.; Schuten, G.; Sajna, S.; Kranjc, A.

    2010-01-01

    Cathodic protection delivers corrosion protection in concrete structures exposed to aggressive environments, e.g. in de-icing salt and marine climates. Working lives of a large number of CP systems are at least more than 13 years and probably more than 25 years, provided a minimum level of maintenan

  2. Renovation of the cathodic protection system

    NARCIS (Netherlands)

    Schuten, G.; Leggedoor, J.; Polder, R.B.; Peelen, W.H.A.

    2003-01-01

    The first system for Cathodic Protection of concrete in the Netherlands was applied to a one bicycle lane of a bridge suffering corrosion due to de-icing salt penetration in 1986. This CP system was based on the Ferex 100S conducting polymer cable anode in a cementitious overlay. Its functioning was

  3. Operational test report - Project W-320 cathodic protection systems

    International Nuclear Information System (INIS)

    Washington Administrative Code (WAC) 173-303-640 specifies that corrosion protection must be designed into tank systems that treat or store dangerous wastes. Project W-320, Waste Retrieval Sluicing System (WRSS), utilizes underground encased waste transfer piping between tanks 241-C-106 and 241-AY-102. Corrosion protection is afforded to the encasements of the WRSS waste transfer piping through the application of earthen ionic currents onto the surface of the piping encasements. Cathodic protection is used in conjunction with the protective coatings that are applied upon the WRSS encasement piping. WRSS installed two new two rectifier systems (46 and 47) and modified one rectifier system (31). WAC 173-303-640 specifies that the proper operation of cathodic protection systems must be confirmed within six months after initial installation. The WRSS cathodic protection systems were energized to begin continuous operation on 5/5/98. Sixteen days after the initial steady-state start-up of the WRSS rectifier systems, the operational testing was accomplished with procedure OTP-320-006 Rev/Mod A-0. This operational test report documents the OTP-320-006 results and documents the results of configuration testing of integrated piping and rectifier systems associated with the W-320 cathodic protection systems

  4. Cathodic Protection Model Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Performs Navy design and engineering of ship and submarine impressed current cathodic protection (ICCP) systems for underwater hull corrosion control and...

  5. Cathodic Protection of Pipeline Using Distributed Control System

    OpenAIRE

    Gopalakrishnan Jayapalan; Ganga Agnihotri; Deshpande, D. M.

    2014-01-01

    Distributed control system (DCS) is available in most of the compressor stations of cross-country pipeline systems. Programmable logic controller (PLC) is used in all the intermediate pigging (IP) stations/sectional valve (SV) stations to collect the field data and to control the remote actuated valves. This paper presents how DCS or PLC can be used for cathodic protection of gas pipelines. Virtual instrumentation (VI) software is used here for simulation and real-time implementation purpose....

  6. Pipeline integrity through cathodic protection

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, N. [Gas Authority India Ltd., New Delhi (India); Khanna, A.S. [Indian Inst. of Technology, Bombay (India)

    2008-07-01

    Pipeline integrity management is defined as a process for assessing and mitigating pipeline risks in an effort to reduce both the likelihood and consequences of incidents. Defects on pipelines result in production losses, environmental losses, as well as loss of goodwill and subsequent financial losses. This presentation addressed pipeline integrity through cathodic protection. It noted that pipeline integrity can be strengthened by successfully controlling, monitoring and mitigating corrosion strategies. It can also be achieved by avoiding external and internal corrosion failures. A good coating offers the advantages of low current density; lower power consumption; low wear of anodes; larger spacing between cathodic protection stations; and minimization of interference problems. The presentation reviewed cathodic protection of cross-country pipelines; a sacrificial cathodic protection system; and an impressed current cathodic protection system. The efficiency of a cathodic system was shown to depend on the use of reliable power sources; proper protection criterion; efficient and effective monitoring of cathodic protection; proper maintenance of the cathodic protection system; and effective remedial measures. Selection criteria, power sources, and a comparison of cathodic protection sources were also presented. Last, the presentation addressed protection criteria; current interruption circuits; monitoring of the cathodic protection system; use of corrosion coupons; advantages of weightless coupons; checking the insulating flanges for shorted bolts; insulated/short casings; anodic and cathodic interference; common corridor problems; and intelligent pigging. tabs., figs.

  7. Cathodic Protection of Pipeline Using Distributed Control System

    Directory of Open Access Journals (Sweden)

    Gopalakrishnan Jayapalan

    2014-01-01

    Full Text Available Distributed control system (DCS is available in most of the compressor stations of cross-country pipeline systems. Programmable logic controller (PLC is used in all the intermediate pigging (IP stations/sectional valve (SV stations to collect the field data and to control the remote actuated valves. This paper presents how DCS or PLC can be used for cathodic protection of gas pipelines. Virtual instrumentation (VI software is used here for simulation and real-time implementation purpose. Analog input channels available in DCS/PLC can be used to measure pipe to soil potential (PSP with the help of half-cell and voltage transducer. Logic blocks available in DCS can be used as low selector switch to select the lowest PSP. Proportional-integral (PI controller available in DCS/PLC can be used for taking the controlling action. PI controller output varies the firing angle of AC phase controller. Phase controller output is rectified, filtered, and fed to the pipeline as cathodic protection current. Proposed scheme utilizes existing infrastructure to control pipeline corrosion.

  8. Permanent cathodic protection monitoring systems for offshore pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Britton, Jim [Deepwater Corrosion Services Inc., Houston, TX (United States)

    2009-07-01

    Historically offshore pipeline cathodic protection monitoring has relied on the use of portable survey techniques. This has typically relied on ROV assisted or surface deployed survey methods. These methods have been shown to have technical as well as economic shortcomings, this is particularly true of buried offshore pipelines where accuracy is always questionable. As more focus is being placed on offshore pipeline integrity, it was time for a new method to emerge. The technology discussed involves the retro-placement of permanent clamp-on monitors onto the pipeline which can measure pipeline to seawater potential as well as current density. The sensors can be interrogated locally using light powered subsea voltage readouts. Application of the technology can be either during pipeline construction, during installation of life extension CP systems, or during routine subsea pipeline interventions. The new method eliminates the need for long cables or expensive acoustic or modulated data transfer and provides all the information required to fully verify CP system performance, thus eliminating the need for expensive close-interval surveys. Some deployment case histories will be presented along with feasibility of application on deep water pipelines and comparative economics. (author)

  9. Cathodic protection to control microbiologically influenced corrosion

    International Nuclear Information System (INIS)

    Information about the cathodic protection performance in environments with microbiologically influenced corrosion (MIC) effects is very fragmented and often contradictory. Not enough is known about the microbial effects on cathodic protection effectiveness, criteria, calcareous deposits, corrosion rates and possible hydrogen embrittlement of titanium and some stainless steel condenser tubes. This paper presents a review of cathodic protection systems, describes several examples of cathodic protection in environments with MIC effects and provides preliminary conclusions about cathodic protection design parameters, criteria and effectiveness in MIC environments. 30 refs

  10. Calculus of cathodic protection system for a storage tank of 42,500 m3

    International Nuclear Information System (INIS)

    This work presents the calculations carried out to install a cathodic protection system for a storage tank of 42,500 m3, including the methodology, the taken data of supplier catalogs and finally the realized adjustments at to install the system in field. Also, the data of electrochemical potential in field at to carry out the installation are included, as well as the interference between a system of galvanic current and other of printed current. (Author)

  11. Reduce operational cost and extend the life of pipeline infrastructure by automating remote cathodic protection systems

    Energy Technology Data Exchange (ETDEWEB)

    Rosado, Elroy [Freewave Technologies, Inc., Boulder, CO (United States). Latin America

    2009-07-01

    Energy and Pipeline Companies wrestle to control operating costs largely affected by new government regulations, ageing buried metal assets, rising steel prices, expanding pipeline operations, new interference points, HCA encroachment, restrictive land use policies, heightened network security, and an ageing soon-to-retire work force. With operating costs on the rise, seemingly out of control, many CP and Operations Professionals look to past best practices in cost containment through automation. Many companies achieve solid business results through deployment of telemetry and SCADA automation of remote assets and now hope to expand this success to further optimize operations by automating remote cathodic protection systems. This presentation will provide examples of how new remote cathodic protection systems are helping energy and pipeline companies address the growing issue of the aging pipeline infrastructure and reduce their costs while optimizing their operations. (author)

  12. A cathodic arc enhanced middle-frequency magnetron sputter system for deposition of hard protective coatings

    International Nuclear Information System (INIS)

    A new cathode arc enhanced magnetron sputter system for deposition of hard protective coatings is reported in this article. This system consists of eight targets: four outer targets are mounted on the wall of the chamber and four inner targets are placed around the center of the chamber. The outer and inner targets form four pair targets and are powered by four middle frequency power supplies. One of the outer targets can run either in the cathode arc mode or in the magnetron sputter mode. The Ti-containing diamond-like carbon nanocomposite coatings were deposited by using this system. The prepared coating exhibits high hardness (∼20 GPa), good adhesion (critical load is 50 N), very low friction coefficient (∼0.07); and excellent tribological performance with a wear rate of 1.4 x 10-16 m3·N-l·m-1. (authors)

  13. Corrosion Control of Kunifer-5 Seawater Piping Systems of Naval Ships by Cathodic Protection Technique

    Directory of Open Access Journals (Sweden)

    M. B. Deshmukh

    1982-01-01

    Full Text Available The cause of premature corrosion of Kunifer-5(copper alloy containing Ni 5 per cent and Fe 1.35 per cent pipes used in seawater piping systems on board ships for feeding seawater to various units has been discussed. It has been shown that the Kunifer-5 alloys suffer from heavy corrosion-erosion attack at unavoidable bends and places where local seawater velocity exceeds the specified limit. The field observations as well as laboratory study have indicated that satisfactory protection of the pipes could be achieved by galvanic cathodic protection using aluminium alloy anodes.

  14. Humectants To Augment Current From Metallized Zinc Cathodic Protection Systems on Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R.; Covino Jr., Bernard S.; Cramer, Stephen D.; Russell, James H. Russell; Bullard, Sophie J.; Collins, W. Keith; Bennett, Jack E. (J.E. Bennett Consulting, Inc.); Soltesz, Steven M. (ODOT); Laylor, H. Martin (ODOT)

    2002-12-01

    Cathodic protection (CP) systems using thermal-sprayed zinc anodes are employed to mitigate the corrosion process in reinforced concrete structures. However, the performance of the anodes is improved by moisture at the anode-concrete interface. Research was conducted to investigate the effect of hydrophilic chemical additives, humectants, on the electrical performance and service life of zinc anodes. Lithium bromide and lithium nitrate were identified as feasible humectants with lithium bromide performing better under galvanic CP and lithium nitrate performing better under impressed current CP. Both humectants improved the electrical operating characteristics of the anode and increased the service life by up to three years.

  15. Improvements in cathodic protection using decoupling methods

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Mauro [IEC - Instalacoes e Engenharia de Corrosao Ltda., Rio de Janeiro, RJ (Brazil); Tachick, Michael [Dairyland Electrical Industries, Inc., Stoughton, WI (United States)

    2005-07-01

    Proper cathodic protection on a structure requires electrical isolation in order to minimize the CP current required, and to shift the voltage of the structure to acceptable levels. This can be difficult to achieve when bonds or grounds connect the structure to other metallic structures of a different galvanic potential. Electrical decoupling methods are available that can provide the needed DC isolation while conducting any AC components to ground, and therefore address the cathodic protection effects while mitigating AC, if present. Substantial improvements in cathodic protection levels, and a reduction in required current, are common results. If the decoupling methods used are rated for the system conditions and are of a fail-safe design, the system can safely address user concerns about AC fault and lightning effects, and can be used in electrical grounding systems. (author)

  16. Cathodic protection -- Addition of 6 anodes to existing rectifier 31

    International Nuclear Information System (INIS)

    This Acceptance Test Procedure (ATP) has been prepared to demonstrate that the cathodic protection system additions are installed, connected, and function as required by project criteria. The cathodic protection system is for the tank farms on the Hanford Reservation. The tank farms store radioactive wastes

  17. Contactless monitoring of cathodic protection

    International Nuclear Information System (INIS)

    Cathodic protection is a very efficient and economical way for protecting underground structures from electrolytic corrosion. The protection is maintained when the potential between the structure surface and the surrounding electrolyte keeps the material in an immune state from corrosion. This means, that the potential on every spot of the protected pipeline should be checked and maintained. Checking the potential can be on few way. The classical way, measuring the pipe to soil potential on the test post spaced 1 - 2 km apart only 'potential samples' can be obtained while 'hot spots' can be left between the test post. The so called 'intensive measurements', when potential is surveyed along the pipeline by a moving electrode connected to a test post. By checking the magnetic field of the returning current along the pipeline, the same anomalies can be found, as by checking the potential distribution along the pipeline, so the places with contacts with foreign structures or coating damages can be located. This measurements can be done by one person walking along the pipeline route. If the pipe route is without obstacles, the measurements can be performed from a vehicle moving along the pipe route. By using a computer based recording device in the vehicle, the measured values can be combined with the location of the anomalies and the printout will show directly the sort and location of the anomalies. Using a helicopter, when up to several hundreds of km pipeline route can be checked daily, makes further improvements. This paper presents current situation on this field, and equipment in FZC I I Oktomvri in Kumanovo. (Author)

  18. Cathodic protection for the bottoms of above ground storage tanks

    Energy Technology Data Exchange (ETDEWEB)

    Mohr, John P. [Tyco Adhesives, Norwood, MA (United States)

    2004-07-01

    Impressed Current Cathodic Protection has been used for many years to protect the external bottoms of above ground storage tanks. The use of a vertical deep ground bed often treated several bare steel tank bottoms by broadcasting current over a wide area. Environmental concerns and, in some countries, government regulations, have introduced the use of dielectric secondary containment liners. The dielectric liner does not allow the protective cathodic protection current to pass and causes corrosion to continue on the newly placed tank bottom. In existing tank bottoms where inadequate protection has been provided, leaks can develop. In one method of remediation, an old bottom is covered with sand and a double bottom is welded above the leaking bottom. The new bottom is welded very close to the old bottom, thus shielding the traditional cathodic protection from protecting the new bottom. These double bottoms often employ the use of dielectric liner as well. Both the liner and the double bottom often minimize the distance from the external tank bottom. The minimized space between the liner, or double bottom, and the bottom to be protected places a challenge in providing current distribution in cathodic protection systems. This study examines the practical concerns for application of impressed current cathodic protection and the types of anode materials used in these specific applications. One unique approach for an economical treatment using a conductive polymer cathodic protection method is presented. (author)

  19. Cathodic protection in simulated geothermal environments

    Energy Technology Data Exchange (ETDEWEB)

    Bandy, R.; van Rooyen, D.

    1983-01-01

    The results of cathodic protection of carbon steel and AISI Type 316 stainless steel in simulated geothermal brines are described. Impressed current tests on carbon steel and stainless steel were conducted under controlled potential, and cathodic protection of carbon steel using zinc sacrificial anodes was studied by monitoring the galvanic current and potential of the couple with a zero-resistance ammeter. Weight-loss measurements and photomicrographs of test coupons were taken whenever necessary to determine the nature of attack and degree of protection. Tests were generally conducted at 90/sup 0/C. However, some tests on carbon steel were conducted up to 150/sup 0/C in a titanium autoclave. Results show that the weight loss of carbon steel can be reduced significantly and the pitting corrosion of the stainless steel can be prevented by shifting the potentials of the metals 60 to 80 mV cathodic to their respective open-circuit potentials.

  20. Effect of cathodic protection on the state of steel reinforcement

    International Nuclear Information System (INIS)

    Damage of reinforced concrete structures is mainly caused by chloride or carbonation induced corrosion of steel. Cathodic protection is a very effective measure for corrosion control of steel in concrete, especially in chloride contaminated concrete. In this paper, effect of cathodic protection on the state of steel reinforcement is presented. Cathodic polarization of reinforcements in concrete was done under different submerged conditions. Cyclic potentiodynamic tests were used to determine the effect of cathodic protection on the behavior of the steel. Pitting appeared on the non-protected steel, but was not observed on the cathodically protected steel. microscopic photographs show that a close film exists on the protected steel, while the non-protected steel's film is loose. Investigated results have proved the effect of cathodic protection in restoring or strengthening passive film on the steel reinforcement

  1. Corrosion and cathodic protection of buried pipes: study, simulation and application of solar energy

    International Nuclear Information System (INIS)

    Cathodic protection is intensively used on steel pipes in petroleum and gas industries. It is a technique used to prevent corrosion which transforms the whole pipe into a cathode of a corrosion cell. Two types of cathodic protection systems are usually used: 1) the galvanic protection systems which use galvanic anodes, also called sacrificial anodes being electrochemically more electronegative than the structure to be protected and 2) the imposed current systems, which through a current generator will deliver a direct current from the anode to the structure to be protected. The aim of this work is to design a cathodic protection system of a pipe by imposed current with auxiliary electric solar energy. (O.M.)

  2. E.M.I Effects of Cathodic Protection on Electromagnetic Flowmeters

    Directory of Open Access Journals (Sweden)

    Ozge Sahin

    2007-01-01

    Full Text Available Electromagnetic flowmeters are used to measure the speed of water flow in water distribution systems. Corrosion problem in metal pipelines can be solved by cathodic protection methods. This paper presents a research on corruptive effects of the cathodic protection system on electromagnetic flowmeter depending on its measuring principle. Experimental measurements are realized on the water distribution pipelines of the Izmir Municipality, Department of Water and Drainage Administration (IZSU in Turkey and measurement results are given. Experimental results proved that the values measured by the electromagnetic flowmeter (EMF are affected by cathodic protection system current. Comments on the measurement results are made and precautions to be taken are proposed.

  3. Applications of cathodic protection for the protection of aqueous and soil corrosion of power plant components

    International Nuclear Information System (INIS)

    Power plant components exposed to environments such as water and soil are susceptible to severe corrosion. Many times the effect of corrosion in power plant components can be catastrophic. The problem is aggravated for underground pipelines due to additional factors such as large network of pipelines, proximity to earth mat, high voltage transmission lines, corrosive chemicals, inadequate approach etc. Other components such as condenser water boxes, internals of pipelines, clarifier bridge structures, cooling water inlet gates and pipes etc. which are in continuous contact with water, are subjected to severe corrosion. The nature and locations of all such components are at places which are not accessible for routine maintenance and hence they require long term reliable protection against corrosion. Experience has shown that anti-corrosive coatings are inadequate in preventing corrosion and due to their location regular maintenance coatings are also not feasible. Under such circumstances the applications of cathodic protection provides a long term solution the design of cathodic protection, for such applications differs from the commonly employed cathodic protection for cross-country pipelines and submerged structures due to other complexities in the plant region and maintenance of the applied system. The present paper intends to discuss the applications of cathodic protection with suitable anti-corrosive coatings for protection of various power plant components and the specific features of each type of application. (author)

  4. Cathodic Protection of the Yaquina Bay Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Bullard, Sophie J.; Cramer, Stephen D.; Covino, Bernard S., Jr.; Holcomb, Gordon R.; Russell, James H.; Laylor, H.M.; Cryer, C.B.

    2001-02-01

    The Yaquina Bay Bridge in Newport, Oregon, was designed by Conde B. McCullough and built in 1936. The 3,223-foot (982 m) structure is a combination of concrete arch approach spans and a steel through arch over the shipping channel. Cathodic protection is used to prevent corrosion damage to the concrete arches. The Oregon Department of Transportation (Oregon DOT) installed a carbon anode coating (DAC-85) on two of the north approach spans in 1985. This anode was operated at a current density of 6.6 mA/m2(0.6 mA/ft2). No failure of the conductive anode was observed in 1990, five years after application, or in 2000, 15 years after application. Thermal-sprayed zinc anodes 20 mils (0.5 mm) thick were applied to half the south approach spans beginning in 1990. Thermal-sprayed zinc anodes 15 mils (0.4 mm) thick were applied to the remaining spans in 1996. These anodes were operated at a current density of 2.2 mA/m2(0.2 mA/ft2). In 1999, four zones on the approach spans were included in a two-year field trial of humectants to improve zinc anode performance. The humectants LiNO3 and LiBr were applied to two zones; the two adjacent zones were left untreated as controls. The humectants substantially reduced circuit resistance compared to the controls.

  5. Cathodic protection criteria for controlling microbially influenced corrosion in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Nekoksa, G. (Corrosion Failure Analysis and Control, San Ramon, CA (USA)); Gutherman, B. (Florida Power Corp., St. Petersburg, FL (USA))

    1991-05-01

    The main objective of this project was to evaluate galvanic corrosion on coupled samples and to determine cathodic protection criteria and effectiveness on four materials in an untreated seawater cooling system with microbially influenced corrosion. Hydrogen embrittlement of two cathodically protected high performance condenser tube materials was also evaluated. The long-term field testing was conducted at the intake structure of Florida Power Corporation's Crystal River Unit 3 Nuclear Power Plant. The test results indicate that Type 304L stainless steel can be galvanically corroded when coupled to Cu/Ni and fully cathodically protected when coupled to a carbon steel anode. Cathodic protection did protect carbon steel, but less than expected from the literature. The cathodic protection effectiveness on carbon steel was approximately 82% at {minus}1.01 V (SCE). To prevent hydrogen embrittlement, the tested titanium or ferritic stainless steel should not be polarized to more negative potentials than {minus}0.75 V (SCE). This report consists of a literature search, preliminary laboratory polarization testing, laboratory testing to determine microbial effects caused by an interruption of cathodic current, development of exposure racks for long-term electrochemical testing and analyses of corrosion, metallurgical, microbial and chemical data. 44 refs., 26 figs., 9 tabs.

  6. Calculus of cathodic protection system for a storage tank of 42,500 m{sup 3}; Calculo del sistema de proteccion catodica para un tanque de almacenamiento de 42,500 m{sup 3}

    Energy Technology Data Exchange (ETDEWEB)

    Arganis J, C. R.; Mondragon C, L. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)], e-mail: carlos.arganis@inin.gob.mx

    2009-10-15

    This work presents the calculations carried out to install a cathodic protection system for a storage tank of 42,500 m{sup 3}, including the methodology, the taken data of supplier catalogs and finally the realized adjustments at to install the system in field. Also, the data of electrochemical potential in field at to carry out the installation are included, as well as the interference between a system of galvanic current and other of printed current. (Author)

  7. Cost analysis of teg-powered and solar-powered cathodic protection system for a-50 km long buried natural gas pipeline located in Sindh, Pakistan

    International Nuclear Information System (INIS)

    Corrosion leaks are of significant concern to oil and gas industry and is considered to be the largest controllable factor in pipeline safety. Cathodic Protection (CP) is a well-established method for preventing corrosion of metallic materials. Electrical power is required and it is usually difficult and expensive to install conventional power lines in remote areas for readily available power supply. Oil/gas organizations make use of thermo-electric generators (TEG), which is relatively expensive in terms of running expenditures. Utilization of renewable energies is now being widely explored due to potential danger of running out of natural resources and dates back mid of 20th century [I]. However, use of solar powered CP system for oil/gas pipelines hasn't been encouraged much in Pakistan, probably due to lack of understanding. A project was undertaken for designing a solar powered CP system for a 52.4 km buried gas pipeline located at Sui/Sara gas fields (Latitude 27.5) of Tullow Pakistan (Dev.) Ltd. in Dharki, Sindh, Pakistan. After detailed analysis of soil condition, electrochemical testing, local climatic variation and cost analysis, it has been revealed that use of solar power is quite feasible for the above-mentioned pipeline section. Cost analysis and comparison have also favored this system since the maintenance cost of the solar-powered system is much less compared to TEG system. Installation cost of the solar system is about 1.57 times the cost of TEG; however, the maintenance cost is only -20% of that for TEG system. The higher installation cost has been estimated to be recoverable in less than one year of service. (author)

  8. Cathodic protection in highly-aggressive geothermal environments

    Energy Technology Data Exchange (ETDEWEB)

    Bandy, R.; van Rooyen, D.

    1982-01-01

    The feasibility of cathodic protection in highly aggressive geothermal environments has been investigated in the laboratory using both impressed current and sacrificial anode techniques. Artificial brines simulating the hypersaline geothermal brines of the Imperial Valley of California and the less aggressive geothermal fluids found in some other parts of the US were used as test environments. Impressed current tests on carbon steel were conducted under controlled potential, and cathodic protection of carbon steel using zinc sacrificial anodes was studied by monitoring the galvanic current and potential of the couple with a zero resistance ammeter. Weight loss measurements were conducted in all cases to determine the amount of protection achieved. Results show that the weight loss generally follows a semi-logarithmic relationship with the amount of potential shift away from the corrosion potential as a result of the impressed current; significant cathodic protection can be achieved by shifting the potential of the order of only 70 to 80 mV. Under certain controlled cathodic conditions, electrocrystallization has been observed on the carbon steel surface, resulting in a small weight gain. For the carbon steel-zinc couple, the potential gradually drifts towards that of the open circuit potential of zinc, resulting in excellent protection for the steel and a relatively tolerable corrosion rate for zinc.

  9. Interaction between Cathodic Protection and Microbially Influenced Corrosion.

    OpenAIRE

    Bujang Masli, Azlan Bin

    2011-01-01

    The present work studied the interaction between cathodic protection and microbiallyinfluenced corrosion (MIC) on the surface of mild steel. Potential trending wasobserved when the currents were held constant, and current trending was observedwhen potentials were held constant. Scanning electron microscopy and energydispersive x-ray spectroscopy were used to study surface deposits on the samples andfurther understand the result of the interaction. Sul...

  10. Photovoltaic power without batteries for continuous cathodic protection

    Science.gov (United States)

    Muehl, W. W., Sr.

    1994-02-01

    The COASTSYSTA designed, installed, and started up on 20 Jan. 1990, a state-of-the-art stand alone photovoltaic powered impressed current cathodic protection system (PVCPSYS) not requiring any auxiliary/battery backup power for steel and iron submerged structures. The PVCPSYS installed on 775' of steel sheet piling of a Navy bulkhead is continuing to provide complete, continuous corrosion protection. This has been well documented by COASTSYSTA and verified on-site by the U.S. Army Civil Engineering Research Laboratory, Champaign, Illinois and the Navy Energy Program Office-Photovoltaic Programs, China Lake, California. The Department of Defense (DoD) Photovoltaic Review Committee and Sandia National Laboratories consider this successful and cost effective system a major advance in the application of photovoltaic power. The PVCPSYS uses only renewable energy and is environmentally clean. A patent is pending on the new technology. Other possible PVCPSYS applications are mothballed ships, docks, dams, locks, bridges, marinas, offshore structures, and pipelines. The initial cost savings by installing a PVCPSYS vs. a conventional CP system was in excess of $46,000.00.

  11. Bacterial corrosion in marine sediments: influence of cathodic protection

    International Nuclear Information System (INIS)

    In order to protect offshore structures from marine corrosion, cathodic protection is widely applied via sacrificial anodes (for example zinc or aluminium) or impressed current. In aerated seawater, steel is considered to be protected when a potential of -8050 mV/Cu.CuSO4 is achieved. In many cases, however this potential must be lowered, due to the activity of microorganisms and more specially sulfate-reducing bacteria (SRB). SRB are obligate anaerobes using sulphate as electron acceptor with resultant production of sulphide. Some of them are also able to use hydrogen as energy source, causing cathodic depolarization of steel surfaces. An experiment was performed to analyze the relation between SRB activity and use of different cathodic potentials applied to mild steel samples in marine sediments. Analytical techniques employed included lipid bio-markers and electrochemical methods. Results indicated an evolution of the bacterial community structure both on the steel and in the sediment, as a function of time and potential. The results also show that cathodically produced hydrogen promotes the growth of SRB (author)

  12. Natural Deposit Coatings on Steel during Cathodic Protection and Hydrogen Ingress

    OpenAIRE

    Wayne R. Smith; Shiladitya Paul

    2015-01-01

    The calcareous coating formed during cathodic protection (CP) in seawater is known to reduce the current demand by hindering the transport of species required to support the cathodic reactions and, thereby, improve the economic performance of CP systems. There is, however, uncertainty as to whether the coating reduces hydrogen uptake or indeed enhances it. To ascertain this, two sets of samples were polarized at −1.1 V (standard calomel electrode, SCE) in 3.5% w/v NaCl and synthetic seawater ...

  13. Characterisation of corrosion products on pipeline steel under cathodic protection

    Energy Technology Data Exchange (ETDEWEB)

    Lanarde, Lise [Gaz de France Research and Development Division, 361 avenue du President Wilson, BP33, 93211 Saint Denis La Plaine (France)]|[UPR15 du CNRS, Laboratoire des Interfaces et Systemes Electrochimiques, Universite Pierre et Marie Curie, C.P. 133, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Campaignolle, Xavier; Karcher, Sebastien; Meyer, Michel [Gaz de France Research and Development Division, 361 avenue du President Wilson, BP33, 93211 Saint Denis La Plaine (France); Joiret, Suzanne [UPR15 du CNRS, Laboratoire des Interfaces et Systemes Electrochimiques, Universite Pierre et Marie Curie, C.P. 133, 4 Place Jussieu 75252 Paris Cedex 05 (France)

    2004-07-01

    Onshore gas transmission lines are conjointly protected against external corrosion by cathodic protection (CP) and organic coatings. If both protection systems are simultaneously faulty, the pipe may be subjected to local loss of protection criteria. Consequently, the development of a corrosion due to the ground intrinsic corrosiveness may occur. To guarantee an optimal and safe use of its 31000 km buried gas transmission network, Gaz de France regularly inspects its pipelines. When indications of metal damage are suspected, excavations are realized to carry out a finer diagnosis and, if necessary, to repair. Whenever, corrosions are encountered, although it occurs very scarcely, it is necessary to evaluate its degree of gravity: activity, mechanism, and kinetics. Among corrosion defects, it is indeed essential to differentiate those active, from those older inactive at the time of excavation, since those last ones may possibly have been annihilated, by a PC reinforcement for instance. Eventually, the identification of the corrosion mechanism and its associated rate will provide an assessment of the risks encountered by other sections of the pipeline similar to that excavated. This study investigates to what extent the degree of gravity (activity, kinetics) of a corrosion can be determined by the characterization and identification of its associated corrosion products. Moreover, it will attempt to relate it to the close environment features as well as to the operating conditions of the pipe. The preliminary results presented in this paper consist in a laboratory study of the time evolution of corrosion products formed on the surface of ordinary low carbon steel samples. The specimens have been previously subjected to various polarization conditions in various aqueous media. The selected solutions are characteristic of ground waters. The main parameters considered for the definition of the media were its initial chemical composition, pH and dissolved gas composition

  14. Fabrication of sacrificial anode cathodic protection through casting method

    International Nuclear Information System (INIS)

    Aluminum is one of the few metals that can be cast by all of the processes used in casting metals. These processes consist of die casting, permanent mold casting, sand casting (green sand and dry sand), plaster casting, investment casting, and continuous casting. Other processes such as lost foam, squeeze casting, and hot isostatic pressing are also used. Permanent mold casting method was selected in which used for fabricating of sacrificial anode cathodic protection. This product was ground for surface finished and fabricated in the cylindrical form and reinforced with carbon steel at a center of the anode. (Author)

  15. Intelligent Pulse Current Cathodic Protection Power Supply Control System for Oil Well Casing%油井套管脉冲电流阴极保护电源控制系统研究

    Institute of Scientific and Technical Information of China (English)

    许庆; 周好斌; 张涛

    2015-01-01

    目的 设计一种智能化油井套管脉冲电流阴极保护电源控制系统,实现电源的智能化运行,确保保护效果最佳. 方法 采用三层闭环控制策略实现电源的自适应调节,采用先进的处理算法对输出电流、输出电压、套管电位进行处理,判断脉冲电流阴极保护的效果,输出相应的PWM控制信号,并对电源的输出参数进行实时调节. 结果 在5. 0 m×0. 5 m×0. 5 m的PVC绝缘水槽中模拟油井套管脉冲电流阴极保护系统,该系统能控制输出频率、幅值、占空比均可独立调节的脉冲电流,使40角钢的保护电位达到-0 . 85 V. 结论 该控制系统可以实现油井套管脉冲电流阴极保护电源的智能化运行,具有投入成本低、可靠性高、功能完善、操作方便等优点.%Objective To design a kind of intelligent control system of pulse current cathodic protection for oil well casing, real-ize the intelligent operation of power supply, and make sure that the cathodic protection of oil well casing pulse current is in the best condition. Methods Three-level closed-loop control strategy was adopted to realize the adaptive regulation of power supply. The advanced processing algorithm was used to deal with the output current, output voltage and casing potential, to determine the protective effect of pulse current cathodic protection, and output the corresponding PWM control signal to achieve real-time control of the power supply. Results A pulse current cathodic protection system of the oil well casing was simulated in the PVC insulated sink of 5. 0 m×0. 5 m×0. 5 m. This control system could control the pulse current with independently adjustable output frequency, amplitude and duty cycle, and the protection potential of the steel reached-0. 85 V. Conclusion This control system could realize the intelligent operation of power supply of pulse current cathodic protection for oil well casing, with advantages of low cost, high reliability

  16. Construction of cathode thermometry and emission test system

    International Nuclear Information System (INIS)

    A thermal cathode (Eimac Y-845) is used for an electron gun at the SPring-8 1-GeV linac. The gun can eject a 180 keV beam of 3 A from the cathode operated at a nominal heater voltage. As the discharge rate between the cathode and the grid becomes high along with the cathode driving time, we replace a cathode with a new one once a year. Before the cathode installation, we have definitely inspected new cathodes by means of a microscope to find defects in their cathodes and grids. However, the emission currents have been sometimes insufficient, or the cathode planes have contacted with the grids due to the heat distortion of the grids. We have suspected that the inadequate cathode temperature may have caused these cathode failures. To monitor the accurate cathode temperature and to reduce the cathode failures, we have constructed a measuring system of the cathode temperatures and the cathode emission currents at the test stand. We redesigned the whenelt and the anode to achieve a space-charge-limited current of 3 A at an acceleration voltage less than -70 kV. The cathode temperature at the nominal heater voltage is expected to be 854degC according to the Richardson-Dushman equation, whereas the actual temperature measured by an infrared thermometer was 813±5degC. This large disagreement is under investigation. (author)

  17. Cathodic protection design of seawater pump by boundary element analysis

    International Nuclear Information System (INIS)

    A three-dimensional boundary element method (3D-BEM) was developed to quantitatively estimate cathodic protection and macro-cell corrosion. To confirm the validity and usefulness of the BEM for analysis of fluid machines handling seawater with complex 3D fields, experiments and analyses were performed. A cast iron vertical pump, with Zn anodes for cathodic protection, was submerged in seawater and operated. Potential distributions inside the pump and anodic currents on the Zn anodes were measured. The polarization curves of the pump material were measured as functions of flow rate, time and temperature, and the polarization characteristics were applied as boundary conditions in performing BEM analysis. Through analyses and experimental work, the following conclusions were obtained. By means of appropriate modelling that takes account of the symmetry of the object being analyzed, it is possible to apply the BEM effectively to corrosion problems of machines with complex 3D fields. Furthermore, extremely high accurate analysis on potential and current density distributions can be performed for fluid machines handling seawater, by precisely ascertaining the dependency of polarization curves on flow rate, time and temperature, and reflecting these dependencies in the boundary conditions. (author)

  18. Investigation of the telluric effects arising along the cathodically protected natural gas pipeline between Karadeniz Ereğli and Düzce

    OpenAIRE

    DEMİREL, Bilal; YALÇIN, Hayri

    2013-01-01

    Cathodic protection is one of the most widely used applications for protecting underground and submarine metallic structures from corrosion. This method is based on providing the electrons, which metallic structures lose as a result of electrolytic reaction, by the cathodic protection system. However, from time to time, it may be possible that there is some unwanted interference input into the metallic structure in such applications. This study is aimed at ascertaining the existence...

  19. Corrosion and cathodic protection of buried pipes: study, simulation and application of solar energy; Corrosion et protection cathodique des canalisations enterrees: etude, simulation et application de l energie solaire

    Energy Technology Data Exchange (ETDEWEB)

    Laoun, Brahim; Serir, Lazhar [Unite de Recherche Appliquee en Energies Renouvelables, URAER / Zone Industrielle Gaar Taam B.P. 88 - 47001, Ghardaia, (Algeria); Niboucha, Karima [Centre de Recherche Scientifique et Technique en Soudage et Controle, CSC / Route de Dely Brahim B.P. 64 - 16000, Cheraga, Alger, (Algeria)

    2006-07-01

    Cathodic protection is intensively used on steel pipes in petroleum and gas industries. It is a technique used to prevent corrosion which transforms the whole pipe into a cathode of a corrosion cell. Two types of cathodic protection systems are usually used: 1) the galvanic protection systems which use galvanic anodes, also called sacrificial anodes being electrochemically more electronegative than the structure to be protected and 2) the imposed current systems, which through a current generator will deliver a direct current from the anode to the structure to be protected. The aim of this work is to design a cathodic protection system of a pipe by imposed current with auxiliary electric solar energy. (O.M.)

  20. Emission current control system for multiple hollow cathode devices

    Science.gov (United States)

    Beattie, John R. (Inventor); Hancock, Donald J. (Inventor)

    1988-01-01

    An emission current control system for balancing the individual emission currents from an array of hollow cathodes has current sensors for determining the current drawn by each cathode from a power supply. Each current sensor has an output signal which has a magnitude proportional to the current. The current sensor output signals are averaged, the average value so obtained being applied to a respective controller for controlling the flow of an ion source material through each cathode. Also applied to each controller are the respective sensor output signals for each cathode and a common reference signal. The flow of source material through each hollow cathode is thereby made proportional to the current drawn by that cathode, the average current drawn by all of the cathodes, and the reference signal. Thus, the emission current of each cathode is controlled such that each is made substantially equal to the emission current of each of the other cathodes. When utilized as a component of a multiple hollow cathode ion propulsion motor, the emission current control system of the invention provides for balancing the thrust of the motor about the thrust axis and also for preventing premature failure of a hollow cathode source due to operation above a maximum rated emission current.

  1. Feed-back from long - term experience with offshore cathodic protection

    Energy Technology Data Exchange (ETDEWEB)

    Brazy, Jean-Louis; Tobiassen, Per [Total S.A., EP Technology Division, CSTJF, Avenue Larribeau, 64000 Pau (France); Roche, Marcel [Total S.A., EP Technology Division, Tour Michelet, 92069 Paris - La Defense (France)

    2004-07-01

    The experience of the Total Group has been compiled in matters of Cathodic Protection (CP) of offshore structures in order to draw conclusions from the cumulated field experience obtained for 40 years in various geographical areas (e.g. North Sea and Gulf of Guinea). More especially, results of monitoring have been used to evaluate the performance in the achieved potentials measured with in-situ reference electrodes together with anode current outputs measured from 'monitored galvanic anodes'. Some 'monitored cathodes' have also been installed giving interesting results on the evolution with time of cathodic current density consumed by steel in seawater. After some initial difficulties due to not adapted designs or low-quality galvanic anodes, CP has been achieved in very good conditions, preventing corrosion and fatigue corrosion failures. Protective potentials have been ensured with much lower current densities than values taken in calculations. It has been demonstrated that anodes have to be sized in such a way that initial output is high enough to ensure a rapid polarization. Current outputs necessary to maintain protection are then much lower, including in geographical areas where protective current density is considered as high. Consequently, residual lifetime of anodes systems is generally much higher than initially foreseen, which often allows interesting prolongation of the platform life when needed. In a few cases, it has been possible to evaluate very precisely any trace of corrosion on the structure and consumption rate and pattern of galvanic anodes when platforms have been removed after their use. The case of the Frcy platform, dismantled after 8 years of operation in the Norwegian sector of North Sea is exposed. It has been possible to check that consumption of anodes has been maximum at the locations foreseen by the modeling. (authors)

  2. Investigation of Corrosion and Cathodic Protection in Reinforced Concrete. II: Properties of Steel Surface Layers

    NARCIS (Netherlands)

    Koleva, D.A.; De Wit, J.H.W.; Van Breugel, K.; Lodhi, Z.F.; Ye, G.

    2007-01-01

    The present study explores the formation of corrosion products on the steel surface (using as-received low carbon construction steel) in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP).

  3. Cathodic protection (citations from the NTIS Data Base). Report for 1964-Mar 80

    International Nuclear Information System (INIS)

    Cathodic protection of ships, moorings, nuclear reactors, underground pipes, underwater equipment, and steel reinforcement are presented in these abstracts of Federally-funded research. The research covers electrochemistry, electrode cleaning, method reliability, and electron microscopy

  4. Cathode scraper system and method of using the same for removing uranium

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, Mark A; Wiedmeyer, Stanley G; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

    2015-02-03

    Embodiments include a cathode scraper system and/or method of using the same for removing uranium. The cathode scraper system includes a plurality of cathode assemblies. Each cathode assembly includes a plurality of cathode rods. The cathode scraper system also includes a cathode scraper assembly configured to remove purified uranium deposited on the plurality of cathode rods. The cathode scraper assembly includes a plurality of scrapers arranged in a lattice, and each scraper of the plurality of scrapers is arranged to correspond to a different cathode rod.

  5. Corrosion and cathodic protection of carbon steel in the tidal zone: Products, mechanisms and kinetics

    International Nuclear Information System (INIS)

    Highlights: • The corrosion product layer forming in the tidal zone is mainly made up of magnetite. • A thin film of magnetite is formed on the steel surface under cathodic protection. • Magnetite is formed during cathodic protection under the calcareous deposit. • Pre-existing corrosion product layers are almost not modified by cathodic protection. - Abstract: Carbon steel coupons were set in the tidal zone of a French seaport for 7 years with or without cathodic protection. The average corrosion rates decreased from 90 μm yr−1 to 9 μm yr−1 under cathodic protection. The corrosion product layers covering the unprotected coupons, characterized by Raman spectroscopy and X-ray diffraction, were mainly made up of magnetite and Fe(III) oxyhydroxides, with magnetite being clearly predominant. The products of the residual corrosion process under cathodic protection, similar to those observed at open circuit potential, formed a thin layer on the steel surface under the calcareous deposit

  6. Plasma distribution of cathodic ARC deposition system

    Energy Technology Data Exchange (ETDEWEB)

    Anders, S.; Raoux, S.; Krishnan, K.; MacGill, R.A.; Brown, I.G. [Lawrence Berkeley National Lab., CA (United States)

    1996-08-01

    The plasma distribution using a cathodic arc plasma source with and without magnetic macroparticle filter has been determined by depositing on a transparent plastic substrate and measuring the film absorption. It was found that the width of the distribution depends on the arc current, and it also depends on the cathode material which leads to a spatial separation of the elements when an alloy cathode is used. By applying a magnetic multicusp field near the exit of the magnetic filter, it was possible to modify the plasma distribution and obtain a flat plasma profile with a constant and homogeneous elemental distribution.

  7. Embedded reference electrodes for corrosion potential monitoring, electrochemical characterization, and controlled-potential cathodic protection

    Science.gov (United States)

    Merten, Bobbi Jo Elizabeth

    A thin wire Ag/AgCl reference electrode was prepared using 50 mum Ag wire in dilute FeCl3. The wire was embedded beneath the polyurethane topcoat of two sacrificial coating systems to monitor their corrosion potential. This is the first report of a reference electrode embedded between organic coating layers to monitor substrate health. The embedded reference electrode (ERE) successfully monitored the corrosion potential of Mg primer on AA 2024-T3 for 800 days of constant immersion in dilute Harrison's solution. Zn primer on steel had low accuracy in comparison. This is in part due to short circuiting by Zn oxidation products, which are much more conductive than Mg corrosion products. Data interpretation was improved through statistical analysis. On average, ERE corrosion potentials are 0.1 to 0.2 V and 0.2 to 0.3 V more positive than a saturated calomel electrode (SCE) in solution for AA 2024-T3 and steel coating systems, respectively. Further research may confirm that ERE obtains corrosion potential information not possible by an exterior, conventional reference electrode. The ERE is stable under polarization. AA 2024-T3 was polarized to -0.95 V vs ERE to emulate controlled potential cathodic protection (CPCP) applications. Polarizations of -0.75 V vs ERE are recommended for future experiments to minimize cathodic delamination. The ERE was utilized to analyze coating mixtures of lithium carbonate, magnesium nitrate, and Mg metal on AA2024-T3. Corrosion potential, low frequency impedance by electrochemical impedance spectroscopy (EIS), and noise resistance by electrochemical noise method (ENM) were reported. Coating performance ranking is consistent with standard electrochemical characterization and visual analyses. The results suggest anti-corrosion resistance superior to a standard Mg primer following 1600 hours of B117 salt spray. Both lithium carbonate and magnesium nitrate are necessary to achieve corrosion protection. Unique corrosion protective coatings for

  8. Cathode power distribution system and method of using the same for power distribution

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, Mark A; Wiedmeyer, Stanley G; Koehl, Eugene R; Bailey, James L; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

    2014-11-11

    Embodiments include a cathode power distribution system and/or method of using the same for power distribution. The cathode power distribution system includes a plurality of cathode assemblies. Each cathode assembly of the plurality of cathode assemblies includes a plurality of cathode rods. The system also includes a plurality of bus bars configured to distribute current to each of the plurality of cathode assemblies. The plurality of bus bars include a first bus bar configured to distribute the current to first ends of the plurality of cathode assemblies and a second bus bar configured to distribute the current to second ends of the plurality of cathode assemblies.

  9. Protected Sulfur Cathode with Mixed Conductive Coating Layer for Lithium Sulfur Battery

    Science.gov (United States)

    Jin, Jun; Wen, Zhaoyin; Wang, Qingsong; Gu, Sui; Huang, Xiao; Chen, Chunhua

    2016-08-01

    A mixed conductive coating layer composed of lithium ion conductive ceramic powder, carbon and binder was introduced on the surface of a sulfur electrode. This coating layer is designed to suppress the migration of lithium polysulfides from the sulfur electrode, and improve the cycling capacity of a lithium sulfur battery. The protected sulfur cathode with a mixed conductive coating layer delivered an initial specific capacity of 1236 mAh g-1 at 0.5C and maintained a capacity of 842 mAh g-1 after 100 cycles. In particular, a soft package battery with protected cathode exhibits improved cycling capacity and excellent rate performance.

  10. Natural Deposit Coatings on Steel during Cathodic Protection and Hydrogen Ingress

    Directory of Open Access Journals (Sweden)

    Wayne R. Smith

    2015-11-01

    Full Text Available The calcareous coating formed during cathodic protection (CP in seawater is known to reduce the current demand by hindering the transport of species required to support the cathodic reactions and, thereby, improve the economic performance of CP systems. There is, however, uncertainty as to whether the coating reduces hydrogen uptake or indeed enhances it. To ascertain this, two sets of samples were polarized at −1.1 V (standard calomel electrode, SCE in 3.5% w/v NaCl and synthetic seawater (ASTM D1141 at 20 °C and the diffusible hydrogen content measured over a period of 530 h. Under such conditions reports suggest a deposit with two distinct layers, comprising an initial brucite layer followed by an aragonite layer. Contrary to other findings, a fine initial layer containing Ca and Mg followed by a brucite layer was deposited with a few specks of Ca-containing zones in synthetic seawater. The hydrogen uptake was found to occur within the initial 100 h of exposure in synthetic seawater whilst it continued without the benefit of a deposit coating, i.e., in 3.5 wt % NaCl solution.

  11. Cathodic protection (citations from the NTIS data base). Report for 1964--Mar 1976

    International Nuclear Information System (INIS)

    Cathodic protection of ships, moorings, nuclear reactors, underground pipes, underwater equipment, and steel reinforcement are presented in abstracts of Federally-funded research. The research covers electrochemistry, electrode cleaning, method reliability and electron microscopy. This updated bibliography contains 151 abstracts, 16 of which are new entries to the previous edition

  12. Magnesium-Based Sacrificial Anode Cathodic Protection Coatings (Mg-Rich Primers for Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Michael D. Blanton

    2012-09-01

    Full Text Available Magnesium is electrochemically the most active metal employed in common structural alloys of iron and aluminum. Mg is widely used as a sacrificial anode to provide cathodic protection of underground and undersea metallic structures, ships, submarines, bridges, decks, aircraft and ground transportation systems. Following the same principle of utilizing Mg characteristics in engineering advantages in a decade-long successful R&D effort, Mg powder is now employed in organic coatings (termed as Mg-rich primers as a sacrificial anode pigment to protect aerospace grade aluminum alloys against corrosion. Mg-rich primers have performed very well on aluminum alloys when compared against the current chromate standard, but the carcinogenic chromate-based coatings/pretreatments are being widely used by the Department of Defense (DoD to protect its infrastructure and fleets against corrosion damage. Factors such as reactivity of Mg particles in the coating matrix during exposure to aggressive corrosion environments, interaction of atmospheric gases with Mg particles and the impact of Mg dissolution, increases in pH and hydrogen gas liberation at coating-metal interface, and primer adhesion need to be considered for further development of Mg-rich primer technology.

  13. Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines

    International Nuclear Information System (INIS)

    The U.S. Department of Energy's (DOE) Hanford Site is responsible for the safe storage, retrieval, treatment, and disposal of approximately 54 million gallons (204 million liters) of radioactive waste generated since the site's inception in 1943. Today, the major structures involved in waste management at Hanford include 149 carbon steel single-shell tanks, 28 carbon-steel double-shell tanks, plus a network of buried metallic transfer lines and ancillary systems (pits, vaults, catch tanks, etc.) required to store, retrieve, and transfer waste within the tank farm system. Many of the waste management systems at Hanford are still in use today. In response to uncertainties regarding the structural integrity of these systems,' an independent, comprehensive integrity assessment of the Hanford Site piping system was performed. It was found that regulators do not require the cathodically protected pipelines located within the Hanford Site to be assessed by External Corrosion Direct Assessment (ECDA) or any other method used to ensure integrity. However, a case study is presented discussing the application of the direct assessment process on pipelines in such a nuclear environment. Assessment methodology and assessment results are contained herein. An approach is described for the monitoring, integration of outside data, and analysis of this information in order to identify whether coating deterioration accompanied by external corrosion is a threat for these waste transfer lines

  14. Application of Direct Assessment Approaches and Methodologies to Cathodically Protected Nuclear Waste Transfer Lines

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, Megan M. [ARES Corporation, Richland, WA (United States); Pikas, Joseph [Schiff Associates, Sugar Land TX (United States); Edgemon, Glenn L. [ARES Corporation, Richland, WA (United States); Philo, Sarah [ARES Corporation, Richland, WA (United States)

    2013-01-22

    The U.S. Department of Energy's (DOE) Hanford Site is responsible for the safe storage, retrieval, treatment, and disposal of approximately 54 million gallons (204 million liters) of radioactive waste generated since the site's inception in 1943. Today, the major structures involved in waste management at Hanford include 149 carbon steel single-shell tanks, 28 carbon-steel double-shell tanks, plus a network of buried metallic transfer lines and ancillary systems (pits, vaults, catch tanks, etc.) required to store, retrieve, and transfer waste within the tank farm system. Many of the waste management systems at Hanford are still in use today. In response to uncertainties regarding the structural integrity of these systems,' an independent, comprehensive integrity assessment of the Hanford Site piping system was performed. It was found that regulators do not require the cathodically protected pipelines located within the Hanford Site to be assessed by External Corrosion Direct Assessment (ECDA) or any other method used to ensure integrity. However, a case study is presented discussing the application of the direct assessment process on pipelines in such a nuclear environment. Assessment methodology and assessment results are contained herein. An approach is described for the monitoring, integration of outside data, and analysis of this information in order to identify whether coating deterioration accompanied by external corrosion is a threat for these waste transfer lines.

  15. Cathodic protection of proton beam piping at Fermi National Accelerator Laboratory, Batavia, Illinois

    International Nuclear Information System (INIS)

    Fermilab has some 25,000 (7,600 meters) feet of bare steel high energy particle beam piping ranging in size from 6-inch to 72-inch (150 mm to 1,800 mm). The piping is used to contain high energy particle beams traveling from the accelerator ring to targets. The cathodic protection required a complex design to overcome many shielding problems and to avoid interference with the many other underground structures on the site. Since cathodic protection current traveling through some of the magnet enclosures could affect beam instrumentation, careful attention had to be paid to dielectric isolation. A combination of surface and deep anodes were used, with special concern for environmental protection

  16. Research and Application of Platinum/tantalum Composite Anode for Cathodic Protection

    Institute of Scientific and Technical Information of China (English)

    WANG Yi; LI Jin; JIA Zhihua; ZHENG Jing

    2012-01-01

    This paper introduces the research status and present situation of application of Pt/Ta composite anode materials for cathodic protection in China.It also introduces the corrosion resistance,bending properties and electrochemical performance in seawater and freshwater of the Pt/Ta composite anode materials for cathodic protection.It points out that compared with other platinum composite anodes,the Pt/Ta composite anode has the advantage of small volume,light weight,big drainage rate,long service life,it possesses superiority to be used in the confluence environment of sea water and fresh water and in the medium condition of resistivity changes at all times.

  17. Wireless monitor for cathodic protection in remote sites: a case study for a university spin-out company

    International Nuclear Information System (INIS)

    This paper describes how a new spin-out company managed to develop a product and bring it to market. The product, a wireless monitor system for use on cathodic protection equipment, is described briefly with emphasis on the main technical challenge of ultra low power demand. The rest of the paper is devoted to the real challenges facing a new spin-out company: ensuring that its product has a market and obtaining the finance to develop it. It shows how government grants and collaboration with an established company can help

  18. The Cathode Strip Chamber Data Acquisition System for CMS

    CERN Document Server

    Bylsma, B G; Gilmore, J R; Gu, J H; Ling, T Y

    2007-01-01

    The Cathode Strip Chamber (CSC) [1] Data Acquisition (DAQ) system for the CMS [2] experiment at the LHC [3] will be described. The CSC system is large, consisting of 218K cathode channels and 183K anode channels. This leads to a substantial data rate of ~1.5GByte/s at LHC design luminosity (1034cm-2s-1) and the CMS first level trigger (L1A) rate of 100KHz. The DAQ system consists of three parts. The first part is on-chamber Cathode Front End Boards (CFEB)[4], which amplify, shape, store, and digitise chamber cathode signals, and Anode Front End Boards (AFEB)[5], which amplify, shape and discriminate chamber anode signals. The second part is the Peripheral Crate Data Acquisition Motherboards (DAQMB), which control the onchamber electronics and the readout of the chamber. The third part is the off-detector DAQ interface boards, which perform real time error checking, electronics reset requests and data concentration. It passes the resulting data to a CSC local DAQ farm, as well as CMS main DAQ [6]. All electron...

  19. Cathodic protection of carbon steel in natural seawater: Effect of sunlight radiation

    International Nuclear Information System (INIS)

    Cathodic protection of metals in seawater is known to be influenced by chemical-physical parameters affecting cathodic processes (oxygen discharge, hydrogen evolution and calcareous deposit precipitation). In shallow seawater, these parameters are influenced by sunlight photoperiod and photosynthetic activity. The results presented here represent the first step in studies dedicated to cathodic protection in shallow photic seawater. This paper reports on carbon steel protected at -850 mV vs. Ag/AgCl (oxygen limiting current regime) in the presence of sunlight radiation but in the absence of biological and photosynthetic activity, the role of which deserves future research. Comparison of results obtained by exposing electrochemical cells to daylight cycles in both biologically inactivated natural seawater and in NaCl 3.5 wt.% solutions showed that sunlight affects current densities and that calcareous deposit interfere with light-currents effects. Sunlight radiation and induced heating of the solution have been separated, highlighting results not otherwise obvious: (1) observed current waves concomitant with sunlight radiation depend fundamentally on solar radiation, (2) solar radiation can determine current enhancements from early to late phases of aragonite crystal growth, (3) a three-day-old CaCO3 layer reduces but does not eliminate the amplitude of the current waves. Theoretical calculations for oxygen limiting currents and additional field tests showed that sunlight, rather than bulk solution heating, is the main cause of daily current enhancements. This was confirmed by polarizations performed at -850 and -1000 mV vs. Ag/AgCl (constant bulk temperature), during which the electrode was irradiated with artificial lighting. This test also confirmed O2 discharge to be the cathodic process involved. A mechanism of radiation conversion to heat in the oxygen diffusion layer region is proposed.

  20. Corrosion protection system for nuclear power plant

    International Nuclear Information System (INIS)

    A cathodic corrosion protection system for a nuclear power plant which employs an ion tank adjacent the main fresh water feed pipe leading to the steam generator to treat water from the main feed pipe and then return the treated water to the main feed pipe to form a corrosion protecting alkaline layer on surfaces of the main feed pipe and the secondary side of the steam generator. The ion tank receives measured amounts of hydrazine to render the water therein substantially conductive and contains ionizable metal anodes which release free metal ions as electric current flows between the anodes and a cathode connection on an ion tank outlet pipe near the main feed water pipe

  1. Simultaneously Harvesting Thermal and Mechanical Energies based on Flexible Hybrid Nanogenerator for Self-Powered Cathodic Protection.

    Science.gov (United States)

    Zhang, Hulin; Zhang, Shangjie; Yao, Guang; Huang, Zhenlong; Xie, Yuhang; Su, Yuanjie; Yang, Weiqing; Zheng, Chunhua; Lin, Yuan

    2015-12-30

    Metal corrosion occurs anytime and anywhere in nature and the corrosion prevention has a great significance everywhere in national economic development and daily life. Here, we demonstrate a flexible hybrid nanogenerator (NG) that is capable of simultaneously or individually harvesting ambient thermal and mechanical energies and used for a self-powered cathodic protection (CP) system without using an external power source. Because of its double peculiarities of both pyroelectric and piezoelectric properties, a polarized poly(vinylidene fluoride) (PVDF) film-based NG was constructed to scavenge both thermal and mechanical energies. As a supplementary, a triboelectric NG was constructed below the pyro/piezoelectric NG to grab ambient mechanical energy. The output power of the fabricated hybrid NG can be directly used to protect the metal surface from the chemical corrosion. Our results not only verify the feasibility of self-powered CP-based NGs, but also expand potential self-powered applications. PMID:26669205

  2. Low voltage cathodic protection for high strength steels. Part 1: Definition of a new aluminum galvanic anode material

    Energy Technology Data Exchange (ETDEWEB)

    Pautasso, J.P. [Ministry of Defense, Paris (France); Le Guyader, H.; Debout, V. [Direction des Constructions Navales Cherbourg (France)

    1998-12-31

    Zn or Al-Zn-In sacrificial anodes are commonly used to protect submerged marine structures from general corrosion and galvanic corrosion. However, such electronegative alloys can also induce stress corrosion cracking or hydrogen embrittlement on high strength steels. Decreasing the electronegative potential applied to the structure, in the suitable range (around {minus}0.80 V vs Ag/AgCl) can significantly reduce the amount of hydrogen produced by the cathodic reaction and thus limit the risk of hydrogen embrittlement. The present work has consisted in determining the criteria for a new cathodic protection system with low voltage anodes and selecting one anode that matches the determined requirements, on the basis of laboratory tests. Among the various alloys tested the Al-O.1% Ga anode provided the most promising results and therefore was selected. The first full scale marine tests performed on an industrial casting of this anode have shown the effectiveness of the Al-O.1% Ga anode in the chosen potential range, with a satisfactory galvanic efficiency in real environments.

  3. High power microwave generation in virtual cathode systems

    International Nuclear Information System (INIS)

    Pulsed high-power microwave generation by means of high current accelerator system has recently become an intensive area of research, the most promising among them being virtual cathode devices or vircators. There are two mechanisms which lead to production of high-power microwaves in vircators. The first deals with electrons, oscillating near the anode and the second with virtual cathode (VC) oscillating as a whole. Generally both mechanisms are presented, but in a given device one may dominate the other. If the anode is thick enough to absorb reflected electrons thus preventing the authors from reentering the diode region, the first mechanism vanished. In this paper the authors discuss the second mechanism, which is realized, for example, in reditron. Anode plasma produced by high-current electron beam passing through the anode is taken into account

  4. Buffer moisture protection system

    International Nuclear Information System (INIS)

    With the present knowledge, bentonite blocks have to be protected from the air relative humidity and from any moisture leakages in the environment that might cause swelling of the bentonite blocks during the 'open' installation phase before backfilling. The purpose of this work was to design the structural reference solution both for the bottom of the deposition hole and for the buffer moisture protection and dewatering system with their integrated equipment needed in the deposition hole. This report describes the Posiva's reference solution for the buffer moisture protection system and the bottom plate on basis of the demands and functional requirements set by long-term safety. The reference solution with structural details has been developed in research work made 2010-2011. The structural solution of the moisture protection system has not yet been tested in practice. On the bottom of the deposition hole a copper plate which protects the lowest bentonite block from the gathered water is installed straight to machined and even rock surface. The moisture protection sheet made of EPDM rubber is attached to the copper plate with an inflatable seal. The upper part of the moisture protection sheet is fixed to the collar structures of the lid which protects the deposition hole in the disposal tunnel. The main function of the moisture protection sheet is to protect bentonite blocks from the leaking water and from the influence of the air humidity at their installation stage. The leaking water is controlled by the dewatering and alarm system which has been integrated into the moisture protection liner. (orig.)

  5. Buffer moisture protection system

    Energy Technology Data Exchange (ETDEWEB)

    Ritola, J.; Peura, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2013-11-15

    With the present knowledge, bentonite blocks have to be protected from the air relative humidity and from any moisture leakages in the environment that might cause swelling of the bentonite blocks during the 'open' installation phase before backfilling. The purpose of this work was to design the structural reference solution both for the bottom of the deposition hole and for the buffer moisture protection and dewatering system with their integrated equipment needed in the deposition hole. This report describes the Posiva's reference solution for the buffer moisture protection system and the bottom plate on basis of the demands and functional requirements set by long-term safety. The reference solution with structural details has been developed in research work made 2010-2011. The structural solution of the moisture protection system has not yet been tested in practice. On the bottom of the deposition hole a copper plate which protects the lowest bentonite block from the gathered water is installed straight to machined and even rock surface. The moisture protection sheet made of EPDM rubber is attached to the copper plate with an inflatable seal. The upper part of the moisture protection sheet is fixed to the collar structures of the lid which protects the deposition hole in the disposal tunnel. The main function of the moisture protection sheet is to protect bentonite blocks from the leaking water and from the influence of the air humidity at their installation stage. The leaking water is controlled by the dewatering and alarm system which has been integrated into the moisture protection liner. (orig.)

  6. Hydrogen Assisted Crack in Dissimilar Metal Welds for Subsea Service under Cathodic Protection

    Science.gov (United States)

    Bourgeois, Desmond

    Dissimilar metal welds (DMWs) are routinely used in the oil and gas industries for structural joining of high strength steels in order to eliminate the need for post weld heat treatment (PWHT) after field welding. There have been reported catastrophic failures in these DMWs, particularly the AISI 8630 steel - Alloy 625 DMW combination, during subsea service while under cathodic protection (CP). This is due to local embrittlement that occurs in susceptible microstructures that are present at the weld fusion boundary region. This type of cracking is known as hydrogen assisted cracking (HAC) and it is influenced by base/filler metal combination, and welding and PWHT procedures. DMWs of two material combinations (8630 steel -- Alloy 625 and F22 steel -- Alloy 625), produced with two welding procedures (BS1 and BS3) in as welded and PWHT conditions were investigated in this study. The main objectives included: 1) evaluation of the effect of materials composition, welding and PWHT procedures on the gradients of composition, microstructure, and properties in the dissimilar transition region and on the susceptibility to HAC; 2) investigation of the influence of microstructure on the HAC failure mechanism and identification of microstructural constituents acting as crack nucleation and propagation sites; 3) assessment of the applicability of two-step PWHT to improve the resistance to HAC in DMWs; 4) establishment of non-failure criterion for the delayed hydrogen cracking test (DHCT) that is applicable for qualification of DMWs for subsea service under cathodic protection (CP).

  7. Advanced Worker Protection System

    International Nuclear Information System (INIS)

    The Advanced Worker Protection System (AWPS) is a liquid-air-based, self-contained breathing and cooling system with a duration of 2 hrs. AWPS employs a patented system developed by Oceaneering Space Systems (OSS), and was demonstrated at their facility in Houston, TX as well as at Kansas State University, Manhattan. The heart of the system is the life-support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack is combined with advanced protective garments, an advanced liquid cooling garment (LCG), a respirator, and communications and support equipment. The prototype unit development and testing under Phase 1 has demonstrated that AWPS has the ability to meet performance criteria. These criteria were developed with an understanding of both the AWPS capabilities and the DOE decontamination and decommissioning (D and D) activities protection needs

  8. Reactor protection system

    International Nuclear Information System (INIS)

    The report describes the reactor protection system (RPS-II) designed for use on Babcock and Wilcox 145-, later 177-, and 205-fuel assembly pressurized water reactors. In this system, relays in the trip logic have been replaced by solid state devices. A calculating module for the low DNBR, pump status, and offset trip functions has replaced the overpower trip (based on flow and imbalance), the power/RC pump trip, and the variable low-pressure trip. Included is a description of the changes from the present Oconee-type reactor protection system (RPS-I), a functional and hardware description of the calculating module, a description of the software programmed in the calculating module, and a discussion of the qualification program conducted to ensure that the degree of protection provided by RPS-II is not less than that provided by previously licensed systems supplied by B and W

  9. Advanced worker protection system

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D ampersand D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D ampersand D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D ampersand D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration

  10. Relation between the cathodic protection and the diagnosis of DCVG; Relacion entre la proteccion catodica y el diagnostico de DCVG

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez N, Miguel A; Malo Tamayo, Jose Maria [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Chavarria M, Rosalba; Duran E, Pablo [Petroleos Mexicanos (Mexico)

    2007-07-01

    The concern of the corrosion in buried pipes has increased with the course of time, the aging of the mechanical protection of the piping, results in defects in the coating, exposing the metal to the corrosive ground, in which the piping is lodged. If suitable levels of cathodic protection do not exist, the corrosion phenomenon in these defects is presented originating unexpected faults in the piping, increasing the costs of maintenance and repair, as well as the diminution in the safety during the operation, as much for the workers as for the communities near the installation of ducts. The technique of Direct Current Voltage Gradient (DCVG), besides locating the defects of the coating in a buried pipe (which are corrosion potential sites), determines corrosion status of the defects and its severity as far as the consumption of protection current that each of these absorbs. Nevertheless, all this information acquires a greater relevance, when it is correlated with the operating conditions of the cathodic protection systems, to be able to emit recommendations that lead to the mitigation or eradication of the corrosion problems, together with a good operation of the protection systems. [Spanish] La preocupacion por la corrosion en tuberias enterradas ha ido en aumento con el transcurso del tiempo, debido al envejecimiento de la proteccion mecanica de las tuberias, el cual da como resultado defectos en el recubrimiento, dejando expuesto el metal en suelo corrosivo, en el que se encuentra alojada la tuberia. Si no existen niveles de proteccion catodica adecuados, se propicia el fenomeno de corrosion en estos defectos, originando fallas inesperadas en las tuberias, incrementando a su vez los costos de mantenimiento y reparacion, asi como la disminucion en la seguridad durante la operacion, tanto para los trabajadores como para las comunidades cercanas a las instalaciones de ductos. La tecnica de Gradiente de Voltaje de Corriente Continua (DCVG), ademas de localizar los

  11. Thermally Sprayed Aluminum (TSA) with Cathodic Protection as Corrosion Protection for Steel in Natural Seawater : Characterization of Properties on TSA and Calcareous Deposit

    OpenAIRE

    Egtvedt, Solveig

    2011-01-01

    Cathodic protection is an effective corrosion protection for structures submerged in seawater. In addition to applying the current need to lower the metal below the protection potential, a resulting increase in interfacial pH leads to precipitation of calcareous deposit. This deposited layer act as a barrier against oxygen diffusion on the surface, hence lowering the current demand of the structure. However, this layer will also hinder the thermal conductivity, and is therefore unwanted at th...

  12. Advanced worker protection system

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D ampersand D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D ampersand D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D ampersand D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment

  13. Advanced worker protection system

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, B.; Duncan, P.; Myers, J. [Oceaneering Space Systems, Houston, TX (United States)

    1995-10-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment.

  14. New concept for cathodic protection of offshore pipelines to reduce hydrogen induced stress cracking (HISC) in high strength 13% Cr stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Eliassen, S.

    2004-05-01

    Cathodic protection (CP) of submarine pipelines has generally been based on a conservative approach, as consequences of failure, to a great extent, are higher than the cost of installations. All design parameters and procedures are based on robust selections. Recent failures on pipelines with supermartensitic stainless steel (SMSS) materials have challenged this approach and laid the way for new design aspects with more realistic use of parameters. A new design concept has been introduced for the cathodic protection of offshore pipelines made from high strength stainless steel materials such as supermartensitic stainless steels (SMSS) with enhanced coating systems such as multilayer polypropylene coatings for combined corrosion protection and thermal insulation. The objectives are to reduce the susceptibility to hydrogen induced stress cracking (HISC) and coating damage. Conditions for the pipeline material, which can cause HISC have been studied and this has motivated the use of the new design concept. The study has been concerned with materials testing, CP-design parameters, CP installation and pipeline attachments, pipeline design, coating quality and direct electrical beating systems for hydrate control. The study has shown that the most critical factors for HISC are pipeline conditions with high stress and strain, especially stress concentrations, potential levels more negative than -0.80 V versus Ag/AgCl, low operating temperatures, coating failures and deep waters (high hydrostatic pressures). The paper gives a detailed overview of the new concept with regard to protection potentials for different pipeline materials; selection of design current density requirements; use of anodes with reduced driving potentials; use of subsea isolating joints; CP design principles; installation methods; compatibility with the direct electrical heating systems for hydrate control. The basis for the design has been the new ISO Draft International Standard 15889-2 on cathodic

  15. Multi-variable mathematical models for the air-cathode microbial fuel cell system

    Science.gov (United States)

    Ou, Shiqi; Kashima, Hiroyuki; Aaron, Douglas S.; Regan, John M.; Mench, Matthew M.

    2016-05-01

    This research adopted the version control system into the model construction for the single chamber air-cathode microbial fuel cell (MFC) system, to understand the interrelation of biological, chemical, and electrochemical reactions. The anodic steady state model was used to consider the chemical species diffusion and electric migration influence to the MFC performance. In the cathodic steady state model, the mass transport and reactions in a multi-layer, abiotic cathode and multi-bacteria cathode biofilm were simulated. Transport of hydroxide was assumed for cathodic pH change. This assumption is an alternative to the typical notion of proton consumption during oxygen reduction to explain elevated cathode pH. The cathodic steady state model provided the power density and polarization curve performance results that can be compared to an experimental MFC system. Another aspect considered was the relative contributions of platinum catalyst and microbes on the cathode to the oxygen reduction reaction (ORR). Simulation results showed that the biocatalyst in a cathode that includes a Pt/C catalyst likely plays a minor role in ORR, contributing up to 8% of the total power calculated by the models.

  16. Incidence des puits sur la protection cathodique des plates-formes fixes Influence of Welles on the Cathodic Protection of Fixed Platform

    Directory of Open Access Journals (Sweden)

    Roche M.

    2006-11-01

    Full Text Available Les puits d'exploitation des gisements pétroliers onshore ne sont pas systématiquement protégés cathodiquement. Par contre les puits offshore supportés par les plates-formes fixes de forage sont nécessairement soumis aux systemes de protection cathodique destinés à celles-ci. La conception de ces systèmes doit prendre en compte la demande en courant des puits, considérée généralement comme parasite. Différentes méthodes de calcul existent, plus ou moins étayées par des considérations scientifiques. Aucune ne peut véritablement prévoir ce que sera la réalité et l'emploi de méthodes de mesure est nécessaire si l'on veut vérifier ce qui se passe exactement. Les différentes méthodes de calcul et de mesure sont passées en revue et critiquées, ce qui conduit à évoquer les points qui nous paraissent devoir être mieux étudiés dans le futur. Production wells on onshore cil fields are not systematically cathodically protected. On the contrary, offshore weils attained from fixed drilling plotforms are necessorily subjected to cathodic protection systems designed for such structures. The design of such systems must Cake into consideration the amount of current demanded by the well, generally considered as parositic current. Different colculoting methods exist, more or less based on scientific considerations. None con truly foresee what the reality will be, and measuring methods have ta be used if we want to check to see exactly what is happening. The different calculating and measuring methods are reviewed and criticized, thus bringing out points that we feel should be further investigated in the future.

  17. ADVANCED WORKER PROTECTION SYSTEM

    International Nuclear Information System (INIS)

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  18. ADVANCED WORKER PROTECTION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Judson Hedgehock

    2001-03-16

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  19. dc cathodic polymerization of trimethylsilane in a closed reactor system

    International Nuclear Information System (INIS)

    dc cathodic polymerization of trimethylsilane (TMS) in a closed reactor system was investigated. The composition of reactive species in the gas phase was monitored during the deposition process by a residual gas analyzer. It was found that, in such a closed plasma system, the deposition of TMS plasma polymers could be visualized as three consecutive, time-delayed, consecutive three fundamental processes. In the early stage of plasma deposition (<60 s after the initiation of plasma), the deposition of plasma polymers was dominated by the polymerization of silicon-based species because the silicon-based species polymerized much quicker than carbon-based species. In the second stage of plasma deposition (between 60 and 120 s), the deposition was then dominated by carbon-based species due to the consumption of silicon in the early stage. In the final stage (more than 120 s), because of the total consumption of all the polymerizable species in the system, the deposition stopped and the deposited plasma polymer surface was continuously treated by nonpolymer forming gas plasma. As a result, the TMS plasma coatings obtained under such operations have a unique chemical structure that gradually changes from a lower carbon (C/Si ratio of ∼1.7 at the film/substrate interface) to carbon rich (C/Si ratio of ∼4.7 on the surface), as identified by x-ray photoelectron spectroscopy analysis

  20. Hydrothermal synthesis and photoelectrochemical performance enhancement of TiO2/graphene composite in photo-generated cathodic protection

    Science.gov (United States)

    Zhang, Weiwei; Guo, Hanlin; Sun, Haiqing; Zeng, Rong-Chang

    2016-09-01

    TiO2/graphene composites were synthesized through one-step hydrothermal method. The composites show an enhancement in photo-generated cathodic protection as the time-dependent profiles of photocurrent responses has confirmed. XRD data show that a bicrystalline framework of anatase and brookite formed as graphene provided donor groups in the hydrothermal process. The transfer of photoinduced electrons in the biphasic TiO2 results in effective electron-hole separation. Moreover, graphene lead to a negative shift of the Fermi level as evidenced by Mott-Schottky analysis, which decreases the Schottky barrier formed in the TiO2 and 304 stainless steel interface and results in the enhancement of photo-generated cathodic protection.

  1. Systems approach to tamper protection

    Energy Technology Data Exchange (ETDEWEB)

    Myre, W. C.; Eaton, M. J.

    1980-01-01

    Tamper-protection is a fundamental requirement of effective containment and surveillance systems. Cost effective designs require that the tamper protection requirements be considered early in the design phase and at the system level. A discussion of tamper protection alternatives as well as an illustrative example system is presented.

  2. The effect of sulphate reducing bacteria on the hydrogen absorption of cathodically protected high strength low alloy steel

    OpenAIRE

    Kilgallon, P. J.

    1994-01-01

    The hydrogen embrittlement of two HSLA steels was studied in conditions typical of the marine environment. Double cantilever beam specimens, heat treated to produce the microstructure in the heat affected zone of a weld, were tested in seawater containing sulphate reducing bacteria (SRB) over a range of cathodic protection (CP) potentials and the threshold stress intensities ([Threshold Stress Intensity]) were recorded. The hydrogen concentration absorbed by the steel ([Surface Hydrogen Con...

  3. Analisa Teknis dan Ekonomis Penggunaan ICCP (Impressed Current Cathodic Protection Dibandingkan dengan Sacrificial Anode dalam Proses Pencegahan Korosi

    Directory of Open Access Journals (Sweden)

    Afif Wiludin

    2013-03-01

    Full Text Available Perlindungan badan kapal  terhadap korosi dengan  menggunakan  metode perlindungan katodik pada prinsipnya adalah sel elektrokimia untuk mengendalikan korosi dengan mengkonsentrasikan reaksi oksigen pada sel galvanik dan menekan korosi pada katoda dalam sel yang sama. Pada proteksi katodik, logam yang akan dilindungi dijadikan katoda dan reaksi oksidasi terjadi di anoda. Ada dua macam cathodic protection yaitu Sacrificial Anode Cathodic Protection (SACP dan Impressed Current Cathodic Protection (ICCP. Dilakukan penelitian tentang analisa teknis dan ekonomis penggunaan ICCP dibandingkan dengan SACP dalam proses pencegahan korosi, kedua sistem dibandingkan dalam jangka 20 tahun, dari segi teknis dengan menggunakan perbandingan perhitungan sesuai standar DnV, yang dibandingkan dari tahap design, tahap instalasi, dan maintenance, dari segi ekonomis perbandingan dibedakan dari tahap pengadaan komponen-komponen sistem, tahap instalasi, dan tahap maintenance. Data perbandingan diperoleh dengan perhitungan sesuai standar, study literature, diskusi dan interview. Hasil perhitungan perbandingan yang diperkirakan selama 20 tahun, dari segi teknis kedua sistem memenuhi standar yang berdasar pada sistem perhitungan standar DnV B-401, sedangkan dari segi ekonomis, biaya untuk sistem ICCP sebesar Rp. 205.405.000,00 dan sistem SACP sebesar Rp. 562.590.000,00, sehingga lebih ekonomis menggunakan sistem ICCP sebesar Rp 357.185.000, 00 atau 63,49% dari biaya untuk sistem SACP

  4. Adaptive protection algorithm and system

    Science.gov (United States)

    Hedrick, Paul [Pittsburgh, PA; Toms, Helen L [Irwin, PA; Miller, Roger M [Mars, PA

    2009-04-28

    An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.

  5. FIRE PROTECTION SYSTEMS AND TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Aristov Denis Ivanovich

    2016-03-01

    Full Text Available The All-Russian Congress “Fire Stop Moscow” was de-voted to the analysis of the four segments of the industry of fire protection systems and technologies: the design of fire protec-tion systems, the latest developments and technologies of active and passive fire protection of buildings, the state and the devel-opment of the legal framework, the practice of fire protection of buildings and structures. The forum brought together the repre-sentatives of the industry of fire protection systems, scientists, leading experts, specialists in fire protection and representatives of construction companies from different regions of Russia. In parallel with the Congress Industrial Exhibition of fire protection systems, materials and technology was held, where manufacturers presented their products. The urgency of the “Fire Stop Moscow” Congress in 2015 organized by the Congress Bureau ODF Events lies primarily in the fact that it considered the full range of issues related to the fire protection of building and construction projects; studied the state of the regulatory framework for fire safety and efficiency of public services, research centers, private companies and busi-nesses in the area of fire safety. The main practical significance of the event which was widely covered in the media space, was the opportunity to share the views and information between management, science, and practice of business on implementing fire protection systems in the conditions of modern economic relations and market realities. : congress, fire protection, systems, technologies, fire protection systems, exhibition

  6. Personal Radiation Protection System

    Science.gov (United States)

    McDonald, Mark; Vinci, Victoria

    2004-01-01

    A report describes the personal radiation protection system (PRPS), which has been invented for use on the International Space Station and other spacecraft. The PRPS comprises walls that can be erected inside spacecraft, where and when needed, to reduce the amount of radiation to which personnel are exposed. The basic structural modules of the PRPS are pairs of 1-in. (2.54-cm)-thick plates of high-density polyethylene equipped with fasteners. The plates of each module are assembled with a lap joint. The modules are denoted bricks because they are designed to be stacked with overlaps, in a manner reminiscent of bricks, to build 2-in. (5.08-cm)-thick walls of various lengths and widths. The bricks are of two varieties: one for flat wall areas and one for corners. The corner bricks are specialized adaptations of the flat-area bricks that make it possible to join walls perpendicular to each other. Bricks are attached to spacecraft structures and to each other by use of straps that can be tightened to increase the strengths and stiffnesses of joints.

  7. Cathodic treatment of the Si-SiO2 system in salt melts

    International Nuclear Information System (INIS)

    This paper studies metal ion transport in SiO2 dielectric layers during their cathodic treatment in salt melts. The preparation of the samples is described. It is shown that an important special feature of cathodic treatments of the silicon-thermal oxide system in salt melts is the formation of a new solid phase at the bottom of the micropores which leads to blocking of the current during subsequent anodic polarization. This is a difference relative to aqueous electrolyes, where cathodic treatment involving hydrogen evolution promotes corrosion of the micropores. The C-V characteristics of the electrolyte-dielectric-semiconductor systems that had been subjected to cathodic treatment in melts are examined at room temperature in 0.0 N KC1. The results are shown

  8. Performance improvement of a PEMFC system controlling the cathode outlet air flow

    Energy Technology Data Exchange (ETDEWEB)

    Feroldi, Diego; Serra, Maria; Riera, Jordi [Institut de Robotica i Informatica Industrial, Universitat Politecnica de Catalunya-Consejo Superior de Investigaciones Cientificas, C. Llorens i Artigas 4, 08028 Barcelona (Spain)

    2007-06-10

    This paper presents a stationary and dynamic study of the advantages of using a regulating valve for the cathode outlet flow in combination with the compressor motor voltage as manipulated variables in a fuel cell system. At a given load current, the cathode input and output flow rate determine the cathode pressure and stoichiometry, and consequently determine the oxygen partial pressure, the generated voltage and the compressor power consumption. In order to maintain a high efficiency during operation, the cathode output regulating valve has to be adjusted to the operating conditions, specially marked by the current drawn from the stack. Besides, the appropriate valve manipulation produces an improvement in the transient response of the system. The influence of this input variable is exploited by implementing a predictive control strategy based on dynamic matrix control (DMC), using the compressor voltage and the cathode output regulating valve as manipulated variables. The objectives of this control strategy are to regulate both the fuel cell voltage and oxygen excess ratio in the cathode, and thus, to improve the system performance. All the simulation results have been obtained using the MATLAB-Simulink environment. (author)

  9. Electrochemical properties of Atomic layer deposition processed CeO2 as a protective layer for the molten carbonate fuel cell cathode

    International Nuclear Information System (INIS)

    Highlights: • Nano-structured CeO2-coated Ni by Atomic Layer Deposition, crystalline as-deposited. • Progressive transformation into a complex surface stable in molten carbonates. • Lower Ni solubility with CeO2 protective coating. • Feasibility of CeO2 coating in Molten Carbonate Fuel Cell cathode conditions. - Abstract: In order to increase the lifetime and performance of the molten carbonate fuel cell, it is compulsory to control the corrosion and dissolution of the state of the art porous nickel oxide cathode. A protective coating constituted by more stable oxides appears to be the best approach. Previous research on CeO2 coatings obtained by DC reactive magnetron sputtering to protect the Molten carbonate fuel cell cathode gave promising results but it was necessary to improve the coating adhesion. In this paper Atomic Layer Deposition, producing high quality, homogeneous and conformal layers, was used to obtain thin layers of CeO2 (20 nm and 120 nm) deposited over porous nickel. CeO2-Ni coated samples were tested as cathodes in Li2CO3-K2CO3 (62-38 mol %) eutectic mixture under standard cathode atmosphere (CO2/air 30:70 vol. %). Structural and morphological characterizations of the nickel coated cathode before and after electrochemical tests in the molten carbonate melt are reported together with the Open Circuit Potential evolution all over 230 h for both the bare porous nickel and the CeO2-coated samples

  10. X- or gamma ray converter and manufacturing method for its cathode system

    International Nuclear Information System (INIS)

    The X-ray converter serves for application in medical diagnostics. For the cathode system of the converter a system based on low-pressure ionography is suited making use of the X-ray photoelectric emission. The electrodes of the cathode system consist of double-layer films with two external conduction layers and an insulator in between. As an auxiliary voltage can be applied between the individual layers the field gradient in the holes may be adjusted, thus increasing the quantum yield. (orig./HP)

  11. X- or gamma ray converter and manufacturing method for its cathode system

    International Nuclear Information System (INIS)

    The X-ray converter serves for application in medical diagnostics. For cathode system of the converter a system based on low-pressure ionography is suited making use of the X-ray photoelectric emission. The electrodes of the cathode system consist of double-layer films with two external conduction layers and an insulator in between. As an auxiliary voltage can be applied between the individual layers the field gradient in the holes may be adjusted, thus increasing the quantum yield. (DG)

  12. Ablative Thermal Protection System Fundamentals

    Science.gov (United States)

    Beck, Robin A. S.

    2013-01-01

    This is the presentation for a short course on the fundamentals of ablative thermal protection systems. It covers the definition of ablation, description of ablative materials, how they work, how to analyze them and how to model them.

  13. Distributed Supervisory Protection Interlock System

    International Nuclear Information System (INIS)

    The Distributed Supervisory Protection Interlock System, DSPI, is under development at the Stanford Linear Accelerator Center for requirements in the areas of personnel protection, beam containment and equipment protection interlocks. The DSPI system, distributed over the application site, consists of segments with microprocessor-based controller and I/O modules, local area networks for communication, and a global supervisor computer. Segments are implemented with commercially available controller and I/O modules arranged in local interlock clusters, and associated software. Segments provide local interlock data acquisition, processing and control. Local area networks provide the communication backbone between segments and a global supervisor processor. The supervisor processor monitors the overall system, reports detail status and provides human interfaces. Details of an R and D test system, which will implement the requirements for personnel protection of 4 typical linear accelerator sectors, will be described. 4 refs., 2 figs

  14. Distributed supervisory protection interlock system

    International Nuclear Information System (INIS)

    The Distributed Supervisory Protection Interlock System, DSPI, is under development at the Stanford Linear Accelerator Center for requirements in the areas of personnel protection, beam containment and equipment protection interlocks. The DSPI system, distributed over the application site, consists of segments with microprocessor-based controller and I/O modules, local area networks for communication, and a global supervisor computer. Segments are implemented with commercially available controller and I/O modules arranged in local interlock clusters, and associated software. Segments provide local interlock data acquisition, processing and control. Local area networks provide the communication backbone between segments and a global supervisor processor. The supervisor processor monitors the overall system, reports detail status and provides human interfaces. Details of an R ampersand D test system, which will implement the requirements for personnel protection of 4 typical linear accelerator sectors, will be described. 4 refs., 2 figs

  15. Self-heated hollow cathode discharge system for charged particle sources and plasma generators

    International Nuclear Information System (INIS)

    This paper presents the results of experimental studies of a new design of discharge system using a self-heated hollow cathode. The discharge system offers certain advantages that are attractive for use in high-dose ion implantation, plasma generators, and plasma electron sources.

  16. Photo-cathode preparation system of the A0 photo-injector

    Energy Technology Data Exchange (ETDEWEB)

    Moyses Kuchnir et al.

    2002-08-23

    The A0 Photo-Injector is an electron accelerator located in the AZero high bay area of Fermilab. A pulsed laser system generates electron bunches by the photo-electric effect when hitting a photo-cathode in a 1.5-cell, 1.3 GHz RF gun. A 9-cell, 1.3 GHz superconducting resonant cavity then accelerates the electrons to 15 MeV. The 10 ps time resolved waveform of the laser pulses is transferred to the electron bunches. This report is focused on the first hardware component of this accelerator, the Photo-cathode Preparation System. The reason for its existence is in the nature of the photo-electric material film used: Cs{sub 2}Te (Cesium Telluride), a very reactive compound that once coated on the cathode requires that it be transported and used in ultra high vacuum (UHV), i.e. < 10{sup -9} Torr.

  17. Power system protection 3 application

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  18. EMI protection for communication systems

    CERN Document Server

    Malaric, Kresimir

    2009-01-01

    This practical reference provides a thorough understanding of how to protect communication systems from intentional and unintentional electromagnetic interference. You learn how to overcome critical problems in both digital and analog communications. This unique resource shows you how to shield equipment from electrical and magnetic fields, design TEM and GTEM-Cell, build capacitive coupling clamps for susceptibility tests, protect electronic equipment with filters, and calculate the measurement uncertainty. You find numerous, well-illustrated examples that make challenging electromagnetics is

  19. Crosstalk, cathode structure and electrical parameters of the MWPCs for the LHCb muon system

    CERN Document Server

    Riegler, W

    2000-01-01

    This note discusses the electrical characteristics of the Multi Wire Proportional Chambers (MWPCs) for the LHCb muon system that were originally developed at PNPI. Optimized layouts for cathode structure and readout traces together with the expected crosstalk numbers are presented. We conclude that cathode pad dimensions should not be smaller than 3 cm in order to limit the cluster size to smaller than 1.2. We also conclude that a front-end electronics input resistance of less than 50 Ohm is preferred in order to limit the capacitive crosstalk. In some regions a resistance of 100 Ohm might be acceptable. In order to limit the crosstalk for chambers with a 'chessboard' cathode structure it is essential that we run the signal traces parallel to the wires.

  20. Modern thyratron crowbar protection systems

    International Nuclear Information System (INIS)

    Two thyratron crowbar systems for high-power klystrons used in linear accelerators are described. The first, contained in an oil filled tank, is a complete system to protect a klystron powered from a 100-kV, 20-A d.c. supply. In the second system a CX1722 glass thyratron, operating in air, has been retrofitted to a test equipment, in place of a spark gap, to protect an Inductive Output Tube (IOT). An important parameter in the choice of the crowbar thyratron is the total coulombs to be switched. Measurements of these follow-on currents are presented. (R.P.) 4 refs.; 10 figs

  1. Reactor Protection Systems. Diverse Approaches

    International Nuclear Information System (INIS)

    Defence in depth design criteria applied to nuclear instrumentation, in particular, to reactor protection systems (RPS), include redundancy, diversity and fail-safe behaviour. Typically, two out of three ('2oo3'), majority-voting systems meet redundancy criteria. A careful analysis of signal levels and polarity and the use of several techniques, such as lives zeros, bias toward safe state, etc. guarantee the same degree of fail-safe behaviour. Diversity criteria, in general, are met by the whole system using more than one method to protect the integrity of reactor (i.e. rod drop plus boron injection), but not for the single instrumentation chain. Moreover, the increasing information needs of supervision systems encourage the use of digital instrumentation in RPS; if the digital instrumentation has software based implementation, the diversity requirement will be mandatory for the instrumentation of each system. In the paper, three possible configurations of the first protection system (rod drop) are analysed. The first one is the traditional hardware approach, the second one is a software based system, and the last one is a proposed mix system. For all configurations, a redundant system two out of four ('2oo4') is assumed. Availability and reliability points of view are taken into account. The proposed mix system is explained in full detail. A discussion about programmable logic and its considerations are introduced. A CPLD based system in a research reactor (RA1) and its functionality are explained. (author)

  2. Evaluation of Cathode-Ray Tube protection for the electronic tabular display subsystem (ETABS) engineering model

    Science.gov (United States)

    Wilson, A. R.

    1981-09-01

    This report describes the safety evaluation of the 25-inch (diagonal) rectangular cathode-ray tube (CRT) that is used in the engineering model of the Electronic Tabular Display Subsystem (ETABS). An evaluation of ETABS will be performed at the Federal Aviation Administration (FAA) Technical Center for possible application in FAA Air Route Traffic Control Centers (ARTCC). The safety evaluation included standard industry pressure testing and special implosion testing on 12 CRT samples. Eleven of the twelve CRT samples satisfactorily met the safety requirements for both the pressure and implosion testing. One CRT cracked when subjected to 45 pounds per square inch (psi) of air pressure; however, the CRT did not implode. The 25-inch rectangular CRT will therefore provide a high degree of safety for use in each of the two tabular displays of the ETABS engineering model.

  3. Controls and Machine Protection Systems

    CERN Document Server

    Carrone, E

    2016-01-01

    Machine protection, as part of accelerator control systems, can be managed with a 'functional safety' approach, which takes into account product life cycle, processes, quality, industrial standards and cybersafety. This paper will discuss strategies to manage such complexity and the related risks, with particular attention to fail-safe design and safety integrity levels, software and hardware standards, testing, and verification philosophy. It will also discuss an implementation of a machine protection system at the SLAC National Accelerator Laboratory's Linac Coherent Light Source (LCLS).

  4. A bipolar membrane combined with ferric iron reduction as an efficient cathode system in microbial fuel cells

    NARCIS (Netherlands)

    Heijne, ter A.; Hamelers, H.V.M.; Wilde, de V.; Rozendal, R.A.; Buisman, C.J.N.

    2006-01-01

    There is a need for alternative catalysts for oxygen reduction in the cathodic compartment of a microbial fuel cell (MFC). In this study, we show that a bipolar membrane combined with ferric iron reduction on a graphite electrode is an efficient cathode system in MFCs. A flat plate MFC with graphite

  5. Design of triode extraction system for a dual hollow cathode ion source

    Institute of Scientific and Technical Information of China (English)

    WANG Jing-Hui; ZHU Kun; ZHAO Wei-Jiang; LIU Ke-Xin

    2011-01-01

    A triode extraction system is designed for a dual hollow cathode ion source being developed at the Institute of Heavy Ion Physics,Peking University.Basic parameters of the plasma are selected after examining the operation principle of the ion source,then the triode extraction system is designed and optimized by using software PBGUNS (for Particle Beam GUN Simulations).The physical design of the system is given in this paper.

  6. Autonomous systems for plant protection

    DEFF Research Database (Denmark)

    Griepentrog, Hans W.; Ruckelshausen, Arno; Jørgensen, Rasmus Nyholm;

    2010-01-01

    autonomous operations related to crop protection probably commercially available in the near future. Scouting and monitoring together with the efficient application of chemicals or mechanical treatments are operations which can be successful automated. Drawbacks are that current systems are lacking robust...

  7. Composite cathode materials development for intermediate temperature solid oxide fuel cell systems

    Science.gov (United States)

    Qin, Ya

    Solid oxide fuel cell (SOFC) systems are of particular interest as electrochemical power systems that can operate on various hydrocarbon fuels with high fuel-to-electrical energy conversion efficiency. Within the SOFC stack, La0.8Sr 0.2Ga0.8Mg0.115Co0.085O3-delta (LSGMC) has been reported as an optimized composition of lanthanum gallate based electrolytes to achieve higher oxygen ionic conductivity at intermediate temperatures, i.e., 500-700°C. The electrocatalytic properties of interfaces between LSGMC electrolytes and various candidate intermediate-temperature SOFC cathodes have been investigated. Sm0.5Sr0.5CoO 3-delta (SSC), and La0.6Sr0.4Co0.2Fe 0.8O3-delta (LSCF), in both pure and composite forms with LSGMC, were investigated with regards to both oxygen reduction and evolution, A range of composite cathode compositions, having ratios of SSC (in wt.%) with LSGMC (wt.%) spanning the compositions 9:1, 8:2, 7:3, 6:4 and 5:5, were investigated to determine the optimal cathode-electrolyte interface performance at intermediate temperatures. All LSGMC electrolyte and cathode powders were synthesized using the glycine-nitrate process (GNP). Symmetrical electrochemical cells were investigated with three-electrode linear dc polarization and ac impedance spectroscopy to characterize the kinetics of the interfacial reactions in detail. Composite cathodes were found to perform better than the single phase cathodes due to significantly reduced polarization resistances. Among those composite SSC-LSGMC cathodes, the 7:3 composition has demonstrated the highest current density at the equivalent overpotential values, indicating that 7:3 is an optimal mixing ratio of the composite cathode materials to achieve the best performance. For the composite SC-LSGMC cathode/LSGMC interface, the cathodic overpotential under 1 A/cm2 current density was as low as 0.085 V at 700°C, 0.062V at 750°C and 0.051V at 800°C in air. Composite LSCF-LSGMC cathode/LSGMC interfaces were found to have

  8. Power system protection 2 systems and methods

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  9. The LHC quench protection system

    CERN Multimedia

    2009-01-01

    The new quench protection system (QPS) has the crucial roles of providing an early warning for any part of the superconducting coils and busbars that develop high resistance, as well as triggering the switch-off of the machine. Over 2000 new detectors will be installed around the LHC to make sure every busbar segment between magnets is monitored and protected. One of the major consolidation activities for the LHC is the addition of two new detectors to the quench protection system. A magnet quench occurs when part of the superconducting cable becomes normally-conducting. When the protection system detects an increased resistance the huge amount of energy stored in the magnet chains is safely extracted and ‘dumped’ into specially designed resistors. In the case of the main dipole chain, the stored energy in a single LHC sector is roughly the same as the kinetic energy of a passenger jet at cruising speed. The first new detector is designed to monitor the superconducting...

  10. Comparative analysis of microbial community between different cathode systems of microbial fuel cells for denitrification.

    Science.gov (United States)

    Li, Chao; Xu, Ming; Lu, Yi; Fang, Fang; Cao, Jiashun

    2016-03-01

    Two types of cathodic biofilm in microbial fuel cells (MFC) were established for comparison on their performance and microbial communities. Complete autotrophic simultaneous nitrification and denitrification (SND) without organics addition was achieved in nitrifying-MFC (N-MFC) with a total nitrogen (TN) removal rate of 0.35 mg/(L·h), which was even higher than that in denitrifying-MFC (D-MFC) at same TN level. Integrated denaturing gradient gel electrophoresis analysis based on both 16S rRNA and nirK genes showed that Alpha-, Gammaproteobacteria were the main denitrifier communities. Some potential autotrophic denitrifying bacteria which can use electrons and reducing power from cathodes, such as Shewanella oneidensis, Shewanella loihica, Pseudomonas aeruginosa, Starkeya novella and Rhodopseudomonas palustris were identified and selectively enriched on cathode biofilms. Further, relative abundance of denitrifying bacteria characterized by nirK/16S ratios was much higher in biofilm than suspended sludge according to real-time polymerase chain reaction. The highest enrichment efficiency for denitrifiers was obtained in N-MFC cathode biofilms, which confirmed autotrophic denitrifying bacteria enrichment is the key factor for a D-MFC system. PMID:26278100

  11. Effect of the cathode potential and sulfate ions on nitrate reduction in a microbial electrochemical denitrification system.

    Science.gov (United States)

    Nguyen, Van Khanh; Park, Younghyun; Yang, Heechun; Yu, Jaecheul; Lee, Taeho

    2016-06-01

    Recently, bioelectrochemical systems have been demonstrated as advantageous for denitrification. Here, we investigated the nitrate reduction rate and bacterial community on cathodes at different cathode potentials [-300, -500, -700, and -900 mV vs. standard hydrogen electrode (SHE)] in a two-chamber microbial electrochemical denitrification system and effects of sulfate, a common nitrate co-contaminant, on denitrification efficiency. The results indicated that the highest nitrate reduction rates (3.5 mg L(-1) days(-1)) were obtained at a cathode potential of -700 mV, regardless of sulfate presence, while a lower rate was observed at a more negative cathode potential (-900 mV). Notably, although sulfate ions generally inhibited nitrate reduction, this effect was absent at a cathode potential of -700 mV. Polymerase chain reaction-denaturing gradient gel electrophoresis revealed that bacterial communities on the graphite-felt cathode were significantly affected by the cathode potential change and sulfate presence. Shinella-like and Alicycliphilus-like bacterial species were exclusively observed on cathodes in reactors without sulfate. Ochrobactrum-like and Sinorhizobium-like bacterial species, which persisted at different cathode potentials irrespective of sulfate presence, were shown to contribute to bioelectrochemical denitrification. This study suggested that a cathode potential of around -700 mV versus SHE would ensure optimal nitrate reduction rate and counteract inhibitory effects of sulfate. Additionally, sulfate presence considerably affects denitrification efficiency and microbial community of microbial electrochemical denitrification systems. PMID:27021845

  12. Interface control of atomic layer deposited oxide coatings by filtered cathodic arc deposited sublayers for improved corrosion protection

    Energy Technology Data Exchange (ETDEWEB)

    Härkönen, Emma, E-mail: emma.harkonen@helsinki.fi [Laboratory of Inorganic Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland); Tervakangas, Sanna; Kolehmainen, Jukka [DIARC-Technology Inc., Espoo (Finland); Díaz, Belén; Światowska, Jolanta; Maurice, Vincent; Seyeux, Antoine; Marcus, Philippe [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7075) – Chimie ParisTech (ENSCP), F-75005 Paris (France); Fenker, Martin [FEM Research Institute, Precious Metals and Metals Chemistry, D-73525 Schwäbisch Gmünd (Germany); Tóth, Lajos; Radnóczi, György [Research Centre for Natural Sciences HAS, (MTA TKK), Budapest (Hungary); Ritala, Mikko [Laboratory of Inorganic Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland)

    2014-10-15

    Sublayers grown with filtered cathodic arc deposition (FCAD) were added under atomic layer deposited (ALD) oxide coatings for interface control and improved corrosion protection of low alloy steel. The FCAD sublayer was either Ta:O or Cr:O–Ta:O nanolaminate, and the ALD layer was Al{sub 2}O{sub 3}–Ta{sub 2}O{sub 5} nanolaminate, Al{sub x}Ta{sub y}O{sub z} mixture or graded mixture. The total thicknesses of the FCAD/ALD duplex coatings were between 65 and 120 nm. Thorough analysis of the coatings was conducted to gain insight into the influence of the FCAD sublayer on the overall coating performance. Similar characteristics as with single FCAD and ALD coatings on steel were found in the morphology and composition of the duplex coatings. However, the FCAD process allowed better control of the interface with the steel by reducing the native oxide and preventing its regrowth during the initial stages of the ALD process. Residual hydrocarbon impurities were buried in the interface between the FCAD layer and steel. This enabled growth of ALD layers with improved electrochemical sealing properties, inhibiting the development of localized corrosion by pitting during immersion in acidic NaCl and enhancing durability in neutral salt spray testing. - Highlights: • Corrosion protection properties of ALD coatings were improved by FCAD sublayers. • The FCAD sublayer enabled control of the coating-substrate interface. • The duplex coatings offered improved sealing properties and durability in NSS. • The protective properties were maintained during immersion in a corrosive solution. • The improvements were due to a more ideal ALD growth on the homogeneous FCAD oxide.

  13. Halon explosion protection system development

    International Nuclear Information System (INIS)

    A loss-of-coolant-accident in a water-cooled nuclear reactor could result in the accumulation of hydrogen and oxygen gases in the containment vessel, ignition of which might produce explosion pressures that exceed the containment design. Protection against suh a hazard can be provided by an inerting system which utilizes Halon 1301 (CF3Br). This inerting gas would be stored in the liquified state and injected only if needed. A development study is reported in which the quantity of Halon required for inerting has been measured, and several envisioned problems investigated. A sub-scale system has been fabicated and used to simulate operation of an actual system under post-LOCA conditions. The testing, together with a system analysis, indicates that the 1301 inerting concept is very suitable for containment application

  14. A combined corrosion protection system for reinforced concrete structures using a carbon fibre mesh

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, M.; Raupach, M. [Institut fuer Bauforschung der RWTH Aachen, IBAC, Institute of Building Materials Research of the Technical University of Aachen, Schinkelstrasse 3 Aachen (Germany)

    2004-07-01

    Cathodic Protection (CP) has become a world-wide used method to protect reinforced concrete structures against reinforcement corrosion. Another method to stop or reduce reinforcement corrosion, at least in case of lower chloride contents is the reduction of the water content of the concrete by applying sealing coatings on the concrete surface. At the Institute of Building Materials Research of Aachen University (IBAC) actually a surface protection system is investigated based on the combination of both methods mentioned above. The idea is to protect the reinforcement within the first years after system installation by cathodic protection until the water content of the concrete has decreased to a level due to the surface coating where the corrosion rate of the reinforcement is uncritical and does not lead to any damage. The system investigated, consists of a carbon fibre net embedded in a special mortar layer as impressed current anode for cathodic protection, covered by a 'dense' cement based polymer modified surface coating. In order to investigate the system, it has been installed on a test area on the weathered upper deck of a parking garage in Aachen, Germany. To investigate the effectiveness regarding the reduction of the water content of the concrete the test area was equipped with so called Multiring-Electrodes (MRE) for depth depended measurement of the concrete resistivity. Reference electrodes for potential and depolarization measurements as well a device for automatic measurement of the protection current were installed to investigate the effectiveness of the impressed current cathodic protection. Additionally 3 re bars were embedded into the concrete of the test area using mortar containing 1, 2 or 3 M.-% chloride by weight of cement respectively, to investigate the influence of the chloride content. First results of the MRE-measurements showing already within the first months after system installation a distinct drying of the concrete cover

  15. System architecture for microprocessor based protection system

    International Nuclear Information System (INIS)

    This paper discusses the architectural design features to be employed by Westinghouse in the application of distributed digital processing techniques to the protection system. While the title of the paper makes specific reference to microprocessors, this is only one (and the newest) of the building blocks which constitutes a distributed digital processing system. The actual system structure (as realized through utilization of the various building blocks) is established through considerations of reliability, licensability, and cost. It is the intent of the paper to address these considerations licenstions as they relate to the architectural design features. (orig.)

  16. Shaping the spatial periodic electron beams in the system of magnetron guns with secondary emission cathodes

    CERN Document Server

    Ajzatskij, N I; Zakutin, V V; Reshetnyak, N G; Romasko, V P; Volkolupov, Yu Ya; Krasnogolovets, M A

    2001-01-01

    The study on the electron beam generation processes in the system of the magnetron guns with the secondary-emission cathodes and anodes in form of periodically positioned metallic pins is carried out. It is shown, that the beam summary current of approximately 22 A is obtained in the system, consisting of four cells, which corresponds to the quadruplicate beam current value of the one cell. The pulse capacity thereby constituted approximately 600 kW. Such beams may be applied in the multipulse microwave devices

  17. Thermal protection system ablation sensor

    Science.gov (United States)

    Gorbunov, Sergey (Inventor); Martinez, Edward R. (Inventor); Scott, James B. (Inventor); Oishi, Tomomi (Inventor); Fu, Johnny (Inventor); Mach, Joseph G. (Inventor); Santos, Jose B. (Inventor)

    2011-01-01

    An isotherm sensor tracks space vehicle temperatures by a thermal protection system (TPS) material during vehicle re-entry as a function of time, and surface recession through calibration, calculation, analysis and exposed surface modeling. Sensor design includes: two resistive conductors, wound around a tube, with a first end of each conductor connected to a constant current source, and second ends electrically insulated from each other by a selected material that becomes an electrically conductive char at higher temperatures to thereby complete an electrical circuit. The sensor conductors become shorter as ablation proceeds and reduced resistance in the completed electrical circuit (proportional to conductor length) is continually monitored, using measured end-to-end voltage change or current in the circuit. Thermocouple and/or piezoelectric measurements provide consistency checks on local temperatures.

  18. Automating occupational protection records systems

    International Nuclear Information System (INIS)

    Occupational protection records have traditionally been generated by field and laboratory personnel, assembled into files in the safety office, and eventually stored in a warehouse or other facility. Until recently, these records have been primarily paper copies, often handwritten. Sometimes, the paper is microfilmed for storage. However, electronic records are beginning to replace these traditional methods. The purpose of this paper is to provide guidance for making the transition to automated record keeping and retrieval using modern computer equipment. This paper describes the types of records most readily converted to electronic record keeping and a methodology for implementing an automated record system. The process of conversion is based on a requirements analysis to assess program needs and a high level of user involvement during the development. The importance of indexing the hard copy records for easy retrieval is also discussed. The concept of linkage between related records and its importance relative to reporting, research, and litigation will be addressed. 2 figs

  19. Protection of Accelerator Hardware: RF systems

    CERN Document Server

    Kim, S-H

    2016-01-01

    The radio-frequency (RF) system is the key element that generates electric fields for beam acceleration. To keep the system reliable, a highly sophisticated protection scheme is required, which also should be designed to ensure a good balance between beam availability and machine safety. Since RF systems are complex, incorporating high-voltage and high-power equipment, a good portion of machine downtime typically comes from RF systems. Equipment and component damage in RF systems results in long and expensive repairs. Protection of RF system hardware is one of the oldest machine protection concepts, dealing with the protection of individual high-power RF equipment from breakdowns. As beam power increases in modern accelerators, the protection of accelerating structures from beam-induced faults also becomes a critical aspect of protection schemes. In this article, an overview of the RF system is given, and selected topics of failure mechanisms and examples of protection requirements are introduced.

  20. Expert System for the LHC CMS Cathode Strip Chambers (CSC) detector

    Energy Technology Data Exchange (ETDEWEB)

    Rapsevicius, Valdas, E-mail: valdas.rapsevicius@cern.ch [Fermi National Accelerator Laboratory, Batavia, IL (United States); Vilnius University, Didlaukio g. 47-325, LT-08303 Vilnius (Lithuania); Juska, Evaldas, E-mail: evaldas.juska@cern.ch [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-02-21

    Modern High Energy Physics experiments are of high demand for a generic and consolidated solution to integrate and process high frequency data streams by applying experts' knowledge and inventory configurations. In this paper we present the Expert System application that was built for the Compact Muon Solenoid (CMS) Cathode Strip Chambers (CSC) detector at the Large Hadron Collider (LHC) aiming to support the detector operations and to provide integrated monitoring. The main building blocks are the integration platform, rule-based complex event processing engine, ontology-based knowledge base, persistent storage and user interfaces for results and control.

  1. Fibre Optic Protection System for Concrete Structures

    Institute of Scientific and Technical Information of China (English)

    J.S.Leng; A.Hameed; D.Winter; R.A.Barnes; G.C.Mays; G.F.Fernando

    2006-01-01

    The design concepts, modelling and implementation of various fibre optic sensor protection systems for development in concrete structures were investigated. Design concepts and on-site requirements for surface-mounted and embedded optical fibre sensor in concrete were addressed. Finite element (FE) modelling of selected sensor protection systems in strain-transfer efficiency from the structure to the sensing region was also studied. And experimental validation of specified sensor protection system was reported. Results obtained indicate that the protection system for the sensors performs adequately in concrete environment and there is very good correlation between results obtained by the protected fibre optic sensors and conventional electrical resistance strain gauges.

  2. Power system protection 4 digital protection and signalling

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  3. RIVER PROTECTION PROJECT SYSTEM PLAN

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, the ORP is responsible for the retrieval, treatment, and disposal of the approximately 57 million gallons of radioactive waste contained in the Hanford Site waste tanks and closure of all the tanks and associated facilities. The previous revision of the System Plan was issued in September 2003. ORP has approved a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. The ORP has established contracts to implement this strategy to establish a basic capability to complete the overall mission. The current strategy for completion of the mission uses a number of interrelated activities. The ORP will reduce risk to the environment posed by tank wastes by: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) for treatment and disposal; (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) and about half of the low-activity waste (LAW) contained in the tank farms, and maximizing its capability and capacity; (3) Developing and deploying supplemental treatment capability or a second WTP LAW Facility that can safely treat about half of the LAW contained in the tank farms; (4) Developing and deploying treatment and packaging capability for transuranic (TRU) tank waste for shipment to and disposal at the Waste Isolation Pilot Plant (WIPP); (5) Deploying interim storage capacity for the immobilized HLW and shipping that waste to Yucca Mountain for disposal; (6) Operating the Integrated Disposal Facility for the disposal of immobilized LAW, along with the associated secondary waste, (7) Closing the SST and DST tank farms, ancillary facilities, and al1 waste

  4. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ; KIRKBRIDE RA; HOHL TM; EMPEY PA; WELLS MN

    2009-09-15

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and

  5. RIVER PROTECTION PROJECT SYSTEM PLAN

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and disposal

  6. Physical protection system design and evaluation

    International Nuclear Information System (INIS)

    The design of an effective physical protection system includes the determination of physical protection system objectives, initial design of a physical protection system, design evaluation, and probably a redesign or refinement. To develop the objectives, the designer must begin by gathering information about facility operation and conditions, such as a comprehensive description of the facility, operating conditions, and the physical protection requirements. The designer then needs to define the threat. This involves considering factors about potential adversaries: class of adversary, adversary's capabilities, and range of adversary's tactics. Next, the designer should identify targets. Determination of whether or not the materials being protected are attractive targets is based mainly on the ease or difficulty of acquisition and desirability of the material. The designer now knows the objectives of the physical protection system, that is, open-quotes what to protect against whom.close quotes The next step is to design the system by determining how best to combine such elements as fences, vaults, sensors and assessment devices, entry control elements, procedures, communication devices, and protective forces personnel to meet the objectives of the system. Once a physical protection system is designed, it must be analyzed and evaluated to ensure it meets the physical protection objectives. Evaluation must allow for features working together to ensure protection rather than regarding each feature separately. Due to the complexity of the protection systems, an evaluation usually requires modeling techniques. If any vulnerabilities are found, the initial system must be redesigned to correct the vulnerabilities and a reevaluation conducted. This paper reviews the physical protection system design and methodology mentioned above. Examples of the steps required and a brief introduction to some of the technologies used in modem physical protections system are given

  7. Promoting an Integral Social Protection System

    OpenAIRE

    World Bank, (WB)

    2013-01-01

    This note reviews the challenges in Mexico s social protection system and possible options to achieve an integral and effective system that is more than the sum of its parts. Mexico s social protection system includes contributory social security schemes, social assistance programs, and labor market programs. The contributory social security schemes offer pensions and health insurance to f...

  8. Aerogel Modified Structural Thermal Protection System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This program will mature and further develop structural syntactic foam insulated integral Thermal Protection System (TPS) designs and materials as an enabling...

  9. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ

    2008-07-10

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, the ORP is responsible for the retrieval, treatment, and disposal of the approximately 57 million gallons of radioactive waste contained in the Hanford Site waste tanks and closure of all the tanks and associated facilities. The previous revision of the System Plan was issued in September 2003. ORP has approved a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. The ORP has established contracts to implement this strategy to establish a basic capability to complete the overall mission. The current strategy for completion of the mission uses a number of interrelated activities. The ORP will reduce risk to the environment posed by tank wastes by: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) for treatment and disposal; (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) and about half of the low-activity waste (LAW) contained in the tank farms, and maximizing its capability and capacity; (3) Developing and deploying supplemental treatment capability or a second WTP LAW Facility that can safely treat about half of the LAW contained in the tank farms; (4) Developing and deploying treatment and packaging capability for transuranic (TRU) tank waste for shipment to and disposal at the Waste Isolation Pilot Plant (WIPP); (5) Deploying interim storage capacity for the immobilized HLW and shipping that waste to Yucca Mountain for disposal; (6) Operating the Integrated Disposal Facility for the disposal of immobilized LAW, along with the associated secondary waste, (7) Closing the SST and DST tank farms, ancillary facilities, and al1 waste

  10. Improving high voltage stability of lithium cobalt oxide/graphite battery via forming protective films simultaneously on anode and cathode by using electrolyte additive

    International Nuclear Information System (INIS)

    Highlights: • The cyclic stability of LiCoO2/graphite battery in voltage range of 3.0-4.5 V is improved by VEC. • VEC inhibits dimension change of the battery after cycling at 4.5 V cutoff voltage. • The SEI formed by VEC on cathode is able to inhibit the cobalt dissolution. • The anodic SEI formed by VEC suppresses the cobalt deposition and the electrolyte decomposition. - Abstract: We report a new finding that high voltage stability of lithium cobalt oxide (LiCoO2)/graphite battery can be improved by using vinyl ethylene carbonate (VEC) as an electrolyte additive. Charge/discharge tests demonstrate that the battery using VEC exhibits significantly improved cyclic and dimensional stability of the 053048-type LiCoO2/graphite pouch cell up to 4.5 V. The capacity retention is 87.0% and the swell value in thickness is 3.1% for the cell with 2.0 wt.% VEC after 400 cycles between 3.0 V and 4.5 V, compared to the values of 38.4% and 38.6%, respectively, for the cell without additive. The characterizations from scanning electron spectroscopy and X-ray photoelectron spectroscopy demonstrate that VEC facilitates the formation of stable solid electrolyte interfaces simultaneously on anode and cathode of the LiCoO2/graphite battery, yielding effective protections for anode and cathode and preventions of the electrolyte decomposition on both electrodes

  11. Enhanced photoelectrochemical cathodic protection performance of the C3N4@In2O3 nanocomposite with quasi-shell–core structure under visible light

    International Nuclear Information System (INIS)

    Highlights: • The C3N4@In2O3 composite with quasi-shell–core structure is prepared. • Photoelectrochemical cathodic protection performance of this composite was studied. • C3N4 coating on In2O3 dramatically enhances its light absorption capability. • C3N4 coating on In2O3 dramatically enhances its photoelectrochemical properties. • C3N4 coating on In2O3 dramatically enhances its electron transfer capability. - Abstract: Carbon nitride@Indium oxide (C3N4@In2O3) composite with quasi-shell–core structure was successfully prepared in this work. The photoinduced open circuit potential and current density results show that the C3N4@In2O3 composite with quasi-shell–core structure could provide the optimal photoelectrochemical cathodic protection capability for 304 stainless steel under visible light when the adding amount of C3N4 in the C3N4@In2O3 composite is 3 wt%. The light absorption capability of the C3N4@In2O3 composite was enhanced due to the synergistic effect of heterojunction structure. According to the HRTEM images, photoinduced Volt–Ampere characteristic curves and electrochemical impedance spectra, the ultrathin coating layer of C3N4 on the surface of In2O3 helps to form a heterojunction electric field at the interface between C3N4 and In2O3, which enhances the separation efficiency of the photogenerated electron–hole pairs. Excessive C3N4 will decline the photoelectrochemical cathodic protection of this composite due to the lower intrinsic electronic mobility and the lower photoelectric conversion property of C3N4

  12. Production of thin carbon stripper foils using heated-substrates in a cathodic arc deposition system

    International Nuclear Information System (INIS)

    The lifetime of carbon stripper foil can have a marked impact on the successful running of a beam line. Standard techniques for production of carbon stripper foils include evaporation of carbon (ec) and laser-pulsed ablation (Ipa). Recent work by a using Ipa has been successful in substantially increasing the lifetime of a very thin foil. The suspected mechanism for the increased lifetime of the foil is that the amorphous carbon foil is density-matched to that of graphite (around 2.26g/cc). In this work, we attempt to reproduce this result by producing carbon stripper foils with a mass-density similar to graphite using a cathodic arc deposition system. The cathodic arc is well known for the production of tetrahedral amorphous carbon: a high density, high stress form of carbon with over 90% sp3-like bonds; to reduce the density of the carbon and promote more graphitic structure, a high bias was initially attempted but this proved unsuccessful. Another method is to use a heated-substrate holder to reduce compressive stress within the deposited film. The performance of the density-matched carbon stripper foils and the implications for future production of high-quality carbon stripper foils in our laboratory will be discussed. (authors)

  13. Optimization of a PIII&D System Using a Cathodic Arc with Titanium

    Science.gov (United States)

    Fazio, M.; Kleiman, A.; Lamas, D. G.; Grondona, D.; Marquez, A.

    2014-05-01

    A plasma immersion ion implantation and deposition (PIII&D) system was recently built at INFIP. A dc cathodic arc with a Ti cathode of 5 cm in diameter and an annular anode of 8cm in diameter was employed as the plasma source. The substrate chamber was electrically insulated and connected with the main discharge chamber through a straight magnetic duct. The discharge current was run at 100 A. The substrate was biased with a pulsed generator (30 kV, 30 A, 0.05 - 3 kHz) based on a pulse transformer controlled by IGBT switches. In this work the optimization of the process as function of the pulse parameters is presented. The characteristics of Ti coatings on steel substrates obtained varying the pulse amplitude from 2 to 12 kV and the pulse frequency from 200 Hz to 400 Hz were analyzed and compared with films grown without biasing the substrate. The thickness was determined weighting the samples before and after the treatment. The morphology was observed with an atomic force microscope. The film structure was studied by x-ray diffraction.

  14. Hierarchical Porous Nickel Cobaltate Nanoneedle Arrays as Flexible Carbon-Protected Cathodes for High-Performance Lithium-Oxygen Batteries.

    Science.gov (United States)

    Xue, Hairong; Wu, Shichao; Tang, Jing; Gong, Hao; He, Ping; He, Jianping; Zhou, Haoshen

    2016-04-01

    Rechargeable lithium-oxygen (Li-O2) batteries are consequently considered to be an attractive energy storage technology because of the high theoretical energy densities. Here, an effective binder-free cathode with high capacity for Li-O2 batteries, needle-like mesoporous NiCo2O4 nanowire arrays uniformly coated on the flexible carbon textile have been in situ fabricated via a facile hydrothermal process followed by low temperature calcination. Because of the material and structural features, the needle-like NiCo2O4 nanowire arrays (NCONWAs) served as a binder-free cathode exhibits high specific capacity (4221 mAh g(-1)), excellent rate capability, and outstanding cycling stability (200 cycles). This cathode based on nonprecious mesoporous metal oxides nanowire arrays has large open spaces and high surface area, providing numerous catalytically active sites and effective transmission pathways for lithium ion and oxygen, and promises the abundant Li2O2 storage. The fast electron transport by directly anchoring on the substrate ensures fast electrochemical reaction process involved with the every nanowire. Furthermore, a bendable Li-O2 battery assembled by using the flexible NCONWAs as the cathode, can be able to light an LED and shows good rate capability and cyclic stability. PMID:26967936

  15. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ; KIRKBRIDE RA; HOHL TM; EMPEY PA; WELLS MN

    2009-09-15

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and

  16. Complex Protection System of Metadata-based Distributed Information Systems

    OpenAIRE

    Kourilov, Denis; Lyadova, Lyudmila

    2008-01-01

    A description of architecture and approaches to the implementation of a protection system of metadatabased adaptable information systems is suggested. Various protection means are examined. The system described is a multilevel complex based on a multiagent system combining IDS functional abilities with structure and logics protection means.

  17. Thermal protection system and related methods

    Science.gov (United States)

    Garbe, Duane J. (Inventor)

    2012-01-01

    A thermal protection system and a method of manufacturing are disclosed. The thermal protection system may be configured to protect a movable joint, for example, a flexible bearing of a rocket motor nozzle. The thermal protection system includes a series of annular shims separated by a plurality of discrete spacers. Each shim of the series of annular shims may have a larger diameter than the previous shim, and the shims may nest. The shims may comprise a thermally stable material, and the discrete spacers may comprise an elastomer. Optionally, an annular bearing protector may separate the annular shims from the flexible bearing.

  18. ENDPOINT PROTECTION SECURITY SYSTEM FOR AN ENTERPRISE

    OpenAIRE

    Ruotsalainen, Petri

    2013-01-01

    The thesis subscriber was Metso Shared Services Ltd. The objective was to find out if Microsoft Forefront Endpoint Protection 2010 (FEP) would be secure and cost-effective enough system to fulfill the requirements of the company’s endpoint protection security system. Microsoft FEP was compared and benchmarked with some other most significant endpoint protection products based on the requirements and definitions of the subscriber. The comparison and evaluation were based on investigation a...

  19. Programmed system for nuclear power plant protection

    International Nuclear Information System (INIS)

    The progress in the field of microprocessors and large scale integration circuits, have incited to introduce this new technologies into nuclear power plant protection system. The hardware and software design principles are briefly listed; then, a quad-redundant protection system for 1300 MWe PWR, developed in France is described

  20. Information support of social protection system

    OpenAIRE

    Kuznetsova, Elena

    2007-01-01

    The article is about the features and problems of informational ensuring of the social protection system in Russia. The author analyzes the current practice of informational ensuring system of social protection, pointing out the flaws. The author proposes possible variants solutions to problems.

  1. Electrodeposition of uranium and transuranic elements onto solid cathode in LiCl-KCl/Cd system for pyrometallurgical partitioning

    International Nuclear Information System (INIS)

    A pyrometallurgical partitioning process is being developed for recovering transuranic elements (TRUs) from high-level liquid waste. In the process, actinides are separated from fission product, especially rare earth elements (REs), by means of an electrorefining technique or a reductive-extraction technique. In this study, electrorefining experiments were carried out in LiCl-KCl/Cd system to recover actinides from salt bath containing actinides and REs. Uranium and neptunium could be depleted from the salt bath and recovered onto a solid cathode with high collection efficiency and high selectivity. Plutonium and americium, however, were difficult to be recovered at high current efficiency because reduction of Nd3+ to Nd2+ at about -1.7 V consumed cathodic current prior to the deposition of Pu or Am. The rotation of the cathode had rather negative effect against deposition of Am and Pu in case of coexistence of much amount of Nd because Nd2+ was removed from the cathode surface quickly and the reaction of Nd3+ to Nd2+ was promoted. At higher current density, Pu and Am could be recovered onto solid cathode but current efficiency became too low. The result indicated that electrorefining technique in the pyro-partitioning was effective for U and Up but not for Pu and Am. (author)

  2. Assessing potential cathodes for resource recovery through wastewater treatment and salinity removal using non-buffered microbial electrochemical systems.

    Science.gov (United States)

    Nikhil, G N; Yeruva, Dileep Kumar; Venkata Mohan, S; Swamy, Y V

    2016-09-01

    The present study evaluates relative functioning of microbial electrochemical systems (MES) for simultaneous wastewater treatment, desalination and resource recovery. Two MES were designed having abiotic cathode (MES-A) and algal biocathode (MES-B) which were investigated with synthetic feed and saline water as proxy of typical real-field wastewater. Comparative anodic and cathodic efficiencies revealed a distinct disparity in both the MES when operated in open circuit (OC) and closed circuit (CC). The maximum open circuit voltage (OCV) read in MES-A and MES-B was about 700mV and 600mV, respectively. Salinity and organic carbon removal efficiencies were noticed high during CC operation as 72% and 55% in MES-A and 60% and 63% in MES-B. These discrete observations evidenced ascribe to the influence of microbial electrochemical induced ion-migration over cathodic reduction reactions (CRR). PMID:27177714

  3. Microbial corrosion and cracking in steel. A concept for evaluation of hydrogen-assisted stress corrosion cracking in cathodically protected high-pressure gas transmission pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Vendelbo Nielsen, L.

    1998-08-01

    An effort has been undertaken in order to develop a concept for evaluation of the risk of hydrogen-assisted cracking in cathodically protected gas transmission pipelines. The effort was divided into the following subtasks: A. Establish a correlation between the fracture mechanical properties of high-strength pipeline steel and the concentration of hydrogen present in the steel. B. Determine the degree hydrogen absorption by cathodically protected steel exposed in natural soil sediment, which include activity of sulphate-reducing bacteria (SRB). C. Compare the above points with fracture mechanical considerations on the level of stress intensity actually present in pipelines during normal operational conditions. The results were used for a discussion - based on well established fracture mechanical relations - on which set of conditions (CP-level and operating pipeline pressure) could give crack propagation. This resulted in threshold curves that can be used for assessment of the risk of hydrogen-assisted cracking as a function of operating pressure and hydrogen content - having the flaw size as discrete parameter. The results are to be used mainly on a conceptual basis, but it was indicated that the requirements for crack propagation include an overprotective CP-condition, a severe sulphate-reducing environment, as well as a large flaw (8 mm or a leak in the present case). A 1 mm flaw (which may be the maximum realistic flaw size) is believed to be unable to provoke crack propagation in this steel. (EG) EFP-95. 16 refs.

  4. On line protection systems for induction motors

    International Nuclear Information System (INIS)

    Protection of induction motors is very important since they are widely used in industry for many applications due to their high robustness, reliability, low cost and maintenance, high efficiency and long service life. So, protecting these motors is crucial for operations. This paper presents a combined protection approach for induction motors. To achieve this, the electrical values of the induction motor were measured with sensitivity ±1% through a data acquisition card and processed with software developed in Visual C++. An on line protection system for induction motors was achieved easily and effectively. The experimental results have shown that the induction motor was protected against the possible problems faced during the operation. The software developed for this protection provides flexible and reliable media for operators and their motors. It is expected that the motor protection achieved in this study might be faster than the classical techniques and also may be applied to larger motors easily after small modifications of the software

  5. Aging assessment for active fire protection systems

    International Nuclear Information System (INIS)

    This study assessed the impact of aging on the performance and reliability of active fire protection systems including both fixed fire suppression and fixed fire detection systems. The experience base shows that most nuclear power plants have an aggressive maintenance and testing program and are finding degraded fire protection system components before a failure occurs. Also, from the data reviewed it is clear that the risk impact of fire protection system aging is low. However, it is assumed that a more aggressive maintenance and testing program involving preventive diagnostics may reduce the risk impact even further

  6. A novel carbon black graphite hybrid air-cathode for efficient hydrogen peroxide production in bioelectrochemical systems

    Science.gov (United States)

    Li, Nan; An, Jingkun; Zhou, Lean; Li, Tian; Li, Junhui; Feng, Cuijuan; Wang, Xin

    2016-02-01

    Carbon black and graphite hybrid air-cathode is proved to be effective for H2O2 production in bioelectrochemical systems. The optimal mass ratio of carbon black to graphite is 1:5 with the highest H2O2 yield of 11.9 mg L-1 h-1 cm-2 (12.3 mA cm-2). Continuous flow is found to improve the current efficiency due to the avoidance of H2O2 accumulation. In the biological system, the highest H2O2 yield reaches 3.29 mg L-1h-1 (0.079 kg m-3day-1) with a current efficiency of 72%, which is higher than the abiotic system at the same current density. H2O2 produced in this system is mainly from the oxygen diffused through this air-cathode (>66%), especially when a more negative cathode potential is applied (94% at -1.0 V). This hybrid air-cathode has advantages of high H2O2 yield, high current density and no need of aeration, which make the synthesis of H2O2 more efficient and economical.

  7. Asymmetric and double-cathode-pad wire chambers for the LHCb muon system

    CERN Document Server

    Kachtchouk, A; Riegler, W; Schmidt, B; Schneider, T; Souvorov, V

    2005-01-01

    We present results from two types of Multi-Wire Proportional Chambers (MWPCs) with wire pitch of 1.5 mm and cathode–cathode distance of 5 mm intended for triggering purposes in the LHCb experiment. Both prototypes use cathode readout because this allows arbitrary segmentation in order to achieve the required granularity. One MWPC prototype uses a symmetric wire–cathode distance (2.5/2.5 mm) with double cathode readout, which doubles the signal compared to reading only one cathode. The second prototype uses an asymmetric wire–cathode distance (1.25/3.75 mm) with single cathode readout which also doubles the signal and in addition reduces the width of the induced charge distribution and therefore reduces the crosstalk for small cathode pads. We also performed a dedicated optimization of readout traces and guard traces in order to reduce the pad–pad crosstalk. Both prototypes show a few hundred volts of operating plateau defined as the region with 99% efficiency in a 20 ns time window. Close to the plate...

  8. Protection of Distribution Systems with Distributed Generation

    OpenAIRE

    Vassbotten, Kristian

    2015-01-01

    In recent years the amount of distributed generation(DG) in distribution systems have increased. This poses problems for the traditional protection scheme, with non-directional over-current relays and fuses. When DG is introduced the load flow in distribution systems are often reversed; there is a surplus of power on the radial. Present thesis seeks to determine the most beneficial protection scheme to use in distribution systems with DG. To investigate the impact of different relays and...

  9. Testing Digital Electronic Protection Systems

    CERN Document Server

    Gabourin, S

    2011-01-01

    This paper outlines the core concepts and realisation of the Safe Machine Parameters Controller (SMPC) testbench, based on a VME crate and LabVIEW program. Its main goal is to ensure the correct function of the SMPC for the protection of the CERN accelerator complex. To achieve this, the tester has been built to replicate the machine environment and operation, in order to ensure that the chassis under test is completely exercised. The complexity of the task increases with the number of input combinations. This paper also outlines the benefits and weaknesses of developing a test suite independently of the hardware being tested, using the “V” approach.

  10. Microsoft System Center Data Protection Manager 2012

    CERN Document Server

    Buchannan, Steve; Gomaa, Islam

    2013-01-01

    This book is a Packt tutorial, walking the administrator through the steps needed to create real solutions to the problems and tasks faced when ensuring that their data is protected. This book is for network administrators, system administrators, backup administrators, or IT consultants who are looking to expand their knowledge on how to utilize DPM to protect their organization's data.

  11. Evolution of the radiation protection system; L'evolution du systeme de protection radiologique

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, R.H. [International Commission on Radiological Protection, Stockholm (Sweden); Schieber, C.; Cordoliani, Y.S. [Societe Francaise de Radioprotection, 92 - Fontenay aux Roses (France); Brechignac, F. [CEA Cadarache, Institut de Radioprotection et de Surete Nucleaire, Dept. de Protection de l' Environnement, 13 - Saint Paul Lez Durance (France)

    2003-07-01

    The evolution of the system of radiological protection: justification for new ICRP recommendations, thoughts of the SFRP work group about the evolution of the system of radiation protection proposed by the ICRP, protection of environment against ionizing radiations seen by the ICRP are the three parts of this chapter. (N.C.)

  12. Reactor protection systems of 500 MWe PHWRs

    International Nuclear Information System (INIS)

    The 500 MWe PHWR has two totally independent, diverse, fast acting shutdown system called Shutdown System 1 (SDS 1) and Shutdown System 2 (SDS 2). The trip generation circuitry of SDS 1 and SDS 2 are known as Reactor Protection System 1 (RPS 1) and Reactor Protection System 2 (RPS 2) respectively. Some of the features specific to 500 MWe reactors are Core Over Power Protection System (COPPS) based upon in core Self Powered Neutron Detector (SPND) signals, use of local two out of three coincidence logic and adoption of overlap testing for RPS 2, use of Fine Impulse Testing (FIT) in RPS 2, testing of the final control elements namely electro-magnetic clutch of individual Shutoff Rods (SRs) of SDS 1 and all the fast acting valves of SDS 2, etc. The two shutdown systems have totally separate sets of sensors and associated signal processing circuitry as well as physical arrangements. A separate computerised test and monitoring unit is used for each of the two shutdown systems. Use of Programmable Digital Comparator (PDC) unit exclusively for reactor protection systems, has been adopted. The capability of PDC unit is enhanced and communication links are provided for its integration in over all system. The paper describes the design features of reactor protection systems. (author)

  13. NDE for Ablative Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for non-destructive evaluation (NDE) methods for quality assessment and defect evaluation of thermal protection systems (TPS). Novel...

  14. NDE for Ablative Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for non-destructive evaluation (NDE) methods for quality assessment and defect evaluation of thermal protection systems (TPS),...

  15. Physical Protection System Effectiveness Evaluation Project

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Whether the performance meets regulation requirements is a key point to physical protection system (PPS) of nuclear material and nuclear facility. To develop PPS effectiveness evaluation methodology and to use risk analysis based on Design Basis

  16. Personnel protect system of cERL

    International Nuclear Information System (INIS)

    The safety management system of Compact Energy Recovery Linac (cERL) is constructed of three systems of the PPS (Personnel Protect System), MMS (Machine Mode System) and the software using EPICS. At first, this system was built for the cERL-injector in 2012. And we modified this system to construction of the return loop of the cERL. We report the details about PPS in this paper. (author)

  17. Requirements for CEC POP machine protection system

    International Nuclear Information System (INIS)

    The requirements of CEC POP machine protection system are meant to prevent damage to a vacuum chamber by a missteered electron beam. In this example, beam energy = 22 MeV, Maximal bunch charge = 5 nC, Maximal repetition rate = 78 kHz, Normalized emittance = 5 mm mrad, Minimal β-function = 1 m. From this information the requirements of the protection system can be calculated by factoring the information into equations to find beam densities and temperature excursions.

  18. Vacuum ultra-violet emission of plasma discharges with high Xe partial pressure using a cathode protective layer with high secondary electron emission

    International Nuclear Information System (INIS)

    In this work, the mechanism of the vacuum ultra-violet (VUV) emission of plasma discharges, with high Xe partial pressure and high ion-induced secondary electrons emission protective layer, is studied by measuring the VUV light emission directly and comparing it with two-dimensional simulations. From the panel measurement, we find that the high intensity of excimer VUV mainly contributes to the high luminous efficacy of SrCaO-plasma display panels (PDP) at a low sustain voltage. The unchanged Xe excitation efficiency indicates that the electron temperature is not decreased by the high secondary electrons emission protective layer, even though the sustain voltage is much lower. From the two-dimensional simulations, we can find that the ratio of excimer VUV to resonant VUV, which is determined by the collision rate in the discharge, is only significantly affected by the Xe partial pressure, while it is independent of the sustain voltage and the secondary-electrons-emission capability of protective layer. The unchanged average electron energy at the moment when the electric field becomes maximum confirms that the improvement of the VUV production efficiency mainly is attributed to the increase in electron heating efficiency of a PDP with high ion-induced secondary electrons emission protective layer. Combining the experimental and the simulation results, we conclude about the mechanism by which the VUV production is improved for the plasma display panel with a high Xe partial pressure and a cold cathode with high ion-induced secondary electrons emission

  19. Distributed systems for protecting nuclear power stations

    International Nuclear Information System (INIS)

    The advantages of distributed control systems for the control of nuclear power stations are obviously of great interest. Some years ago, EPRI, (Electric Power Research Institute) showed that multiplexing the signals is technically feasible, that it enables the availability specifications to be met and costs to be reduced. Since then, many distributed control systems have been proposed by the manufacturers. This note offers some comments on the application of the distribution concept to protection systems -what should be distributed- and ends with a brief description of a protection system based on microprocessors for the pressurized power stations now being built in France

  20. Power system protection 1 principles and components

    CERN Document Server

    Association, Electricity Training

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  1. Preparation, characterization and degradation investigations of cathode catalysts for automotive PEM fuel cells systems

    OpenAIRE

    Marcu, Alina

    2014-01-01

    This research was designed to meet Daimler systematic efforts to address future electromobility demands. The work focuses on developing potential cathode catalysts and tests procedures to be employed in prototype fuel cells. In order to achieve commercial cost-competitive polymer electrolyte membrane fuel cells (PEM FC), the following major challenges have to be addressed: i) The catalytic mass activity of the cathode catalysts has to be at least 0.44 A/mg Pt representing an increased factor ...

  2. System Design of Cold Weather Protective Clothing

    Directory of Open Access Journals (Sweden)

    Nishkam Kasturiya

    1999-12-01

    Full Text Available System design of cold weather protective clothing is a critical process, as it involvesconsideration of the effects of a number of external and internal parameters like environmental factors and physical, physico-mechanical and psychological parameters. The bulk and weightof the textile materials used in protective clothing should be as low as possible, so thatclothing does not create physical stress and discomfort to the soldier and does not affecthis combat duties adversely. This paper discusses the essential factors involved in thedesigning of cold weather protective clothing and different insulating materials availablein the market for developing better protective clothing. Different stores'developed at theDefence Materials & Stores Research & Development Establishment, Kanpur, the order ofarrangement of various insulating materials in those stores and the protection level achievedare discussed.

  3. Self-energized credential system for the plutonium protection system

    International Nuclear Information System (INIS)

    The elements of the Self-Energized Credential System installed at Hanford, Washington, as part of the Plutonium Protection System operational demonstration are described. System concepts, electromagnetic fields, and component electronics are discussed. 9 figures

  4. [Artificial intelligence] AI for protection systems

    Energy Technology Data Exchange (ETDEWEB)

    Aggarwal, R.; Johns, A.

    1997-12-31

    The reliable operation of large power systems with small stability margins is highly dependent on control systems and protection devices. Progress in the field of microprocessor systems and demanding requirements in respect of the performance of protective relays are the reasons for digital device applications to power system protection. The superiority of numeric protection over its analogue alternatives is attributed to such factors as accurate extraction of the fundamental voltage and current components through filtering, functional benefits resulting from multi-processor design and extensive self-monitoring, etc. However, all these reasons have not led to a major impact on speed, sensitivity and selectivity of primary protective relays, and the gains are only marginal; this is so because conventional digital relays still rely on deterministic signal models and a heuristic approach for decision making, so that only a fraction of the information contained within voltage and current signals as well as knowledge about the plant to be protected is used. The performance of digital relays may be substantially improved if the decision making is based on elements of artificial intelligence (AI). (Author)

  5. Ethical foundations of the radiological protection system.

    Science.gov (United States)

    Cho, K W

    2016-06-01

    The International Commission on Radiological Protection (ICRP) has established Task Group 94 under Committee 4 to develop a report on the ethical foundations of the system of radiological protection. The aim of this report is to consolidate the basis of ICRP recommendations, to improve understanding of the system, and to provide a basis for communication on radiation risk and its perception. Through a series of workshops organised by the Commission in cooperation with the International Radiation Protection Association and its associate societies involving radiological protection professionals and specialists of ethics around the world, Task Group 94 has identified the key ethical and social values underpinning the system of radiological protection. The purpose of eliciting the ethical principles and values of the radiological protection system is not only to clarify the rationale for recommendations made by the Commission, but also to assist in discussions related to its practical implementation. A clear understanding of the ethical principles will help resolve dilemmas caused by potential conflicts in actions that might be considered, or decisions that must be made. PMID:26980798

  6. Advanced Protection & Service Restoration for FREEDM Systems

    Science.gov (United States)

    Singh, Urvir

    A smart electric power distribution system (FREEDM system) that incorporates DERs (Distributed Energy Resources), SSTs (Solid State Transformers - that can limit the fault current to two times of the rated current) & RSC (Reliable & Secure Communication) capabilities has been studied in this work in order to develop its appropriate protection & service restoration techniques. First, a solution is proposed that can make conventional protective devices be able to provide effective protection for FREEDM systems. Results show that although this scheme can provide required protection but it can be quite slow. Using the FREEDM system's communication capabilities, a communication assisted Overcurrent (O/C) protection scheme is proposed & results show that by using communication (blocking signals) very fast operating times are achieved thereby, mitigating the problem of conventional O/C scheme. Using the FREEDM System's DGI (Distributed Grid Intelligence) capability, an automated FLISR (Fault Location, Isolation & Service Restoration) scheme is proposed that is based on the concept of 'software agents' & uses lesser data (than conventional centralized approaches). Test results illustrated that this scheme is able to provide a global optimal system reconfiguration for service restoration.

  7. The protection system to Brazilian Nuclear Program

    International Nuclear Information System (INIS)

    The Sistema de Protecao ao Programa Nuclear Brasileiro-SIPRON (Protection System to Brazilian Nuclear Program) was established in 1980. It is intended to accomplish in only one system, all the actions related to security and protection for Nuclear Facilities in Brazil. The author presents in detail the protection system SIPRON, describing the system structure and organization, the functions and obligations of the system involved main organizations, as well as, the system operation and behaviour during an postulated occurrence of a nuclear emergency. It is also described an Exercise that happened in June of 1997 at the Nuclear Power Plant (NPP) Angra I, after two simulated tests in December of 1996 and April of 1997. The NPP Angra I Emergency Plan Exercise was a good opportunity to test the SIPRON structure and preparedness program. It was verified, included by International Atomic Energy Agency observers, the system involved organizations effectiveness and the procedures efficacy to protect the public and the environmental. Finally, it is shown the SIPRON activities of routine, the system obstacles and the expected future performances. (author)

  8. Formal Protection Architecture for Cloud Computing System

    Institute of Scientific and Technical Information of China (English)

    Yasha Chen; Jianpeng Zhao; Junmao Zhu; Fei Yan

    2014-01-01

    Cloud computing systems play a vital role in national securi-ty. This paper describes a conceptual framework called dual-system architecture for protecting computing environments. While attempting to be logical and rigorous, formalism meth-od is avoided and this paper chooses algebra Communication Sequential Process.

  9. Management information system on radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Grossi, Pablo Andrade; Souza, Leonardo Soares de; Figueiredo, Geraldo Magela, E-mail: pabloag@cdtn.b, E-mail: lss@cdtn.b, E-mail: gmf@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Considering the flux complexity and the multi source information of all radiation protection activities on nuclear organizations, an effective management information system based on technology, information and people is necessary to improve the safety on all processes and operations subjected to radiation risks. An effective management information system is an essential tool to highlight the strengths and weaknesses and identify behaviors and trends on the activities requiring radiation protection programs. Such kind of distinct knowledge is useful to reach an effective management and support the human decision-making on nuclear organization. This paper presents a management information system based on Brazilian directives and regulations on radiation protection. Due to its generic characteristics, this radiation protection control system can be implemented on any nuclear organization by reediting the non restricted parameters which could differ considering all facilities and laboratories expected on-site with diverse technologies applications. This system can be considered as a powerful tool applied on the continuous management of radiation protection activities on nuclear organizations and research institutes as well as for long term planning, not only indicating how the safety activities are going, but why they are not going as well as planned where that is the case. (author)

  10. Mechanistic Insight in the Function of Phosphite Additives for Protection of LiNi0.5Co0.2Mn0.3O2 Cathode in High Voltage Li-Ion Cells.

    Science.gov (United States)

    He, Meinan; Su, Chi-Cheung; Peebles, Cameron; Feng, Zhenxing; Connell, Justin G; Liao, Chen; Wang, Yan; Shkrob, Ilya A; Zhang, Zhengcheng

    2016-05-11

    Triethlylphosphite (TEP) and tris(2,2,2-trifluoroethyl) phosphite (TTFP) have been evaluated as electrolyte additives for high-voltage Li-ion battery cells using a Ni-rich layered cathode material LiNi0.5Co0.2Mn0.3O2 (NCM523) and the conventional carbonate electrolyte. The repeated charge/discharge cycling for cells containing 1 wt % of these additives was performed using an NCM523/graphite full cell operated at the voltage window from 3.0-4.6 V. During the initial charge process, these additives decompose on the cathode surface at a lower oxidation potential than the baseline electrolyte. Impedance spectroscopy and post-test analyses indicate the formation of protective coatings by both additives on the cathode surface that prevent oxidative breakdown of the electrolyte. However, only TTFP containing cells demonstrate the improved capacity retention and Coulombic efficiency. For TEP, the protective coating is also formed, but low Li(+) ion mobility through the interphase layer results in inferior performance. These observations are rationalized through the inhibition of electrocatalytic centers present on the cathode surface and the formation of organophosphate deposits isolating the cathode surface from the electrolyte. The difference between the two phosphites clearly originates in the different properties of the resulting phosphate coatings, which may be in Li(+) ion conductivity through such materials. PMID:27090502

  11. Distance Protection for Microgrids in Distribution System

    DEFF Research Database (Denmark)

    Lin, Hengwei; Liu, Chengxi; Guerrero, Josep M.;

    2015-01-01

    Owing to the increasing penetration of distributed generation, there are some challenges for the conventional protection in distribution system. Bidirectional power flow and variable fault current because of the various operation modes may lead to the selectivity and sensitivity of the overcurrent...... protection decreased. This paper adopts distance protection for one mid-voltage level microgrid in Aalborg, Denmark. Different operation modes of the network are analyzed and tested in the paper. The simulation results show that the variations of the fault currents seen by the forward relays are much larger...... than the backward relays. Meanwhile, the fault currents change little with the randomness of renewable energy except the intermittence. Finally, it shows that the designed distance protection has satisfactory performance to clear the various faults....

  12. Televison assessment and identification system for the plutonium protection system

    Energy Technology Data Exchange (ETDEWEB)

    Greenwoll, D.A.

    1979-02-01

    This report covers the selection, description, and use of the components comprising the Television Assessment and Identification System in the Hanford Plutonium Protection System. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Facility Physical Protection Program.

  13. Dependability Evaluation of Advanced Diverse Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Yang Gyun; Lee, Yoon Hee; Sohn, Se Do; Baek, Seung Min [KEPCO, Daejeon (Korea, Republic of); Lee, Sang Jeong [Chungnam National University, Daejeon (Korea, Republic of)

    2014-08-15

    For the mitigation of anticipated transients without scram (ATWS) as well as common cause failure (CCF) within the plant protection system (PPS) and the emergency safety feature . component control system (ESF-CCS), the diverse protection system (DPS) has been designed by KEPCO Engineering and Construction Company. Recently KEPCO E and C has developed the advanced diverse protection system (ADPS), which has four redundant channels, in an attempt to enhance a fault-tolerant capability of the system. For the evaluation of overall system improvement effects of the ADPS compared with the DPS, the dependability evaluation results are described herein. For all dependability attributes, this paper suggests a practical dependability evaluation method which uses quantitative dependability scores and indices. An overall dependability evaluation index (DEI) for the ADPS is evaluated with the average value of reliability/ security/maintainability/safety indices (i.e., RID, SID, MID, and SID') for dependability. The evaluation results show that the DEI value of ADPS can be improved by approximately 23% compared with that of the DPS, thanks to its fault-tolerant system architecture, software design changes, and external interface design features. Several suggestions have been made, in this paper, of an overall quantitative dependability evaluation method for the nuclear instrumentation and control (I and C) systems including the DPS and ADPS, and the usefulness of dependability evaluation on nuclear I and C systems has been confirmed.

  14. Dependability Evaluation of Advanced Diverse Protection System

    International Nuclear Information System (INIS)

    For the mitigation of anticipated transients without scram (ATWS) as well as common cause failure (CCF) within the plant protection system (PPS) and the emergency safety feature . component control system (ESF-CCS), the diverse protection system (DPS) has been designed by KEPCO Engineering and Construction Company. Recently KEPCO E and C has developed the advanced diverse protection system (ADPS), which has four redundant channels, in an attempt to enhance a fault-tolerant capability of the system. For the evaluation of overall system improvement effects of the ADPS compared with the DPS, the dependability evaluation results are described herein. For all dependability attributes, this paper suggests a practical dependability evaluation method which uses quantitative dependability scores and indices. An overall dependability evaluation index (DEI) for the ADPS is evaluated with the average value of reliability/ security/maintainability/safety indices (i.e., RID, SID, MID, and SID') for dependability. The evaluation results show that the DEI value of ADPS can be improved by approximately 23% compared with that of the DPS, thanks to its fault-tolerant system architecture, software design changes, and external interface design features. Several suggestions have been made, in this paper, of an overall quantitative dependability evaluation method for the nuclear instrumentation and control (I and C) systems including the DPS and ADPS, and the usefulness of dependability evaluation on nuclear I and C systems has been confirmed

  15. A prediction-based self-adaptive feed-forward control system for thermionic cathode microwave electron gun

    International Nuclear Information System (INIS)

    Beijing Free Electron Laser Facility (BFEL) adopts a thermionic cathode microwave electron gun as its RF linac injector. For relatively long macro-pulse operation, the back-bombardment effect deteriorates the characteristics of the accelerated electron beam. So the authors developed a prediction-based self-adaptive feed-forward control system to compensate for the beam-loading. The system is operational and some experimental results have been obtained, which suggests that the system is effective to improve the beam quality, and that it's capable of dealing with complicated systems whose response is time-variable, non-linear and of long delay

  16. Assessment of physical protection systems: EVA method

    International Nuclear Information System (INIS)

    CEA's missions in various sectors of activity such as nuclear, defence, industrial contracts and the associated regulatory requirements, make it necessary to develop a strategy in the field of physical protection. In particular, firms having nuclear materials are subject to the July 25, 1980 law no.80-572 on the protection and control of nuclear materials. A holding permit delivered by the regulatory authority is conditioned to the protection by the operator of the nuclear materials used. In France it is the nuclear operator who must demonstrate, in the form of a security study, that potential aggressors would be neutralised before they could escape with the material. To meet these requirements, we have developed methods to assess the vulnerability of our facilities. The EVA method, the French acronym for 'Evaluation de la vulnerabilite des Acces' (access vulnerability system) allows dealing with internal and external threats involving brutal actions. In scenarios relating to external threat, the intruders get past the various barriers of our protection system, attempting to steal a large volume of material in one swoop and then escape. In the case of internal threat, the goal is the same. However, as the intruder usually has access to the material in the scope of his activities, the action begins at the level of the target. Our protection system is based on in-depth defense where the intruders are detected and then delayed in their advance towards their target to allow time for intervention forces to intercept them

  17. Introduction to Enhanced Protective Film Systems

    Institute of Scientific and Technical Information of China (English)

    LIU Chunlin; DAVID Palermo; LI Guoqiang; SUN Jianyun; CHEN Suwen

    2008-01-01

    An explosive blast mitigation alternative has increased the safety of structures by using "catcher" systems.These systems " catch" or repel the failure of the window or in-fill wall protecting life and property from ballistic shards or fragments.They can be designed to be standalone in new construction and structural retrofits or used to augment structural hardening techniques.Cables,fabrics,and thin gauge sheet steel are examples of catcher systems used in the past.A new and evolving category of catcher systems are based on polymeric materials that can be used for both wall and window upgrades.These products are a proven blast mitigation concept and K&C Protective Technologies Pte Ltd (KCPT) together with Sherwin-Williams(SW) use KCPT's blast engineering capacity and SW's material engineering principles to create engineered systems for even greater in-use performance.

  18. Basic study of cold fusion. 2. Development of the measurement system of deuterium loading ratio in palladium cathode

    International Nuclear Information System (INIS)

    A measurement system of deuterium loading ratio in the palladium cathode, which is one of the most important factors for cold fusion phenomena, especially excess heat generation, has been introduced to the simultaneous measurement device of heat, neutron and gamma-ray of heavy water electrolysis that had been developed. Pressure of the gas phase in the closed electrolysis cell and electro-conductivity of the palladium cathode were measured to calculate the deuterium loading ratio. The measured ratio by means of each method is adequate compared with the reported results, and turned out to reach approximately 0.87. Simultaneous and continuous measurement of deuterium loading ratio with heat and neutron made reproduction of the situation of cold fusion phenomena and precision measurement of the heat generation possible. (author)

  19. Thermal Protection System with Staggered Joints

    Science.gov (United States)

    Simon, Xavier D. (Inventor); Robinson, Michael J. (Inventor); Andrews, Thomas L. (Inventor)

    2014-01-01

    The thermal protection system disclosed herein is suitable for use with a spacecraft such as a reentry module or vehicle, where the spacecraft has a convex surface to be protected. An embodiment of the thermal protection system includes a plurality of heat resistant panels, each having an outer surface configured for exposure to atmosphere, an inner surface opposite the outer surface and configured for attachment to the convex surface of the spacecraft, and a joint edge defined between the outer surface and the inner surface. The joint edges of adjacent ones of the heat resistant panels are configured to mate with each other to form staggered joints that run between the peak of the convex surface and the base section of the convex surface.

  20. An integrated numerical protection system (SPIN)

    International Nuclear Information System (INIS)

    Developments in technology have now made it possible to perform more sophisticated protection functions which follow more closely the physical phenomena to be monitored. For this reason the Commissariat a l'energie atomique, Merlin-Gerin, Cerci and Framatome have embarked on the joint development of an Integrated Numerical Protection System (SPIN) which will fulfil this objective and will improve the safety and availability of power stations. The system described involves the use of programmed numerical techniques and a structure based on multiprocessors. The architecture has a redundancy of four. Throughout the development of the project the validity of the studies was confirmed by experiments. A first numerical model of a protection function was tested in the laboratory and is now in operation in a power station. A set of models was then introduced for checking the main components of the equipment finally chosen prior to building and testing a prototype. (author)

  1. Evolution of the system of radiological protection

    International Nuclear Information System (INIS)

    The development of new radiological protection recommendations by the International Commission on Radiological Protection (ICRP) continues to be a strategically important undertaking, both nationally and internationally. With the growing recognition of the importance of stakeholder aspects in radiological protection decision making, regional and cultural aspects have also emerged as having potentially significant influence on how protection of the public, workers and the environment are viewed. Differing cultural aspects should therefore be considered by the ICRP in its development of new recommendations. Based on this assumption, the NEA organised the Asian Regional Conference on the Evolution of the System of Radiological Protection to express and explore views from the Far East. Held in Tokyo on 24-25 October 2002, the conference included presentations by the ICRP Chair as well as by radiological protection experts from Japan, the Republic of Korea, China and Australia. The distinct views and needs of these countries were discussed in the context of their regional and cultural heritages. These views, along with a summary of the conference results, are presented in these proceedings. (author)

  2. Study of the chemical structure of films formed during transpassive to passive transitions on a cathodically protected AISI 430 ferritic stainless steel

    International Nuclear Information System (INIS)

    AISI 430 stainless steel can be cathodically protected in highly oxidizing solutions. The freely corroding potential of this stainless steel in such solutions is transpassive. In the protecting process this potential is lowered from the transpassive to the passive zone by applying potentiostatic techniques. The chemical structures of the surface films formed during the various stages of this potential shift were investigated by X-ray and Auger electron spectroscopies combined with Ar+ ion sputtering for depth profiling and by scanning electron microscopy. The shift is accompanied by two distinct phenomena: a) Increase of the concentration ratio of the oxidized to the metallic states of the iron and of the chromium present in the film. This implies that films formed in the passive zone are thicker than those formed in the transpassive one, a fact which is also revealed by the Auger depth profiles. b) Formation of a layered structure in the passive zone which is characterized by chromium surface segregation in the film. Three layers were detected. The layer at the metal film interface is composed of Cr+3 oxide whereas the two layers above it are composed of mixed iron and chromium oxides with the iron being primarily of Fe+2 type in the intermediate layer and of Fe+3 type in the outer one. (author)

  3. Prevention and the Child Protection System

    Science.gov (United States)

    Waldfogel, Jane

    2009-01-01

    The nation's child protection system (CPS) has historically focused on preventing maltreatment in high-risk families, whose children have already been maltreated. But, as Jane Waldfogel explains, it has also begun developing prevention procedures for children at lower risk--those who are referred to CPS but whose cases do not meet the criteria for…

  4. Validation of reactor core protection system

    International Nuclear Information System (INIS)

    Reactor COre Protection System (RCOPS), an advanced core protection calculator system, is a digitized one which provides core protection function based on two reactor core operation parameters, Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD). It generates a reactor trip signal when the core condition exceeds the DNBR or LPD design limit. It consists of four independent channels adapted a two-out-of-four trip logic. System configuration, hardware platform and an improved algorithm of the newly designed core protection calculator system are described in this paper. One channel of RCOPS was implemented as a single channel facility for this R and D project where we performed final integration software testing. To implement custom function blocks, pSET is used. Software test is performed by two methods. The first method is a 'Software Module Test' and the second method is a 'Software Unit Test'. New features include improvement of core thermal margin through a revised on-line DNBR algorithm, resolution of the latching problem of control element assembly signal and addition of the pre-trip alarm generation. The change of the on-line DNBR calculation algorithm is considered to improve the DNBR net margin by 2.5%-3.3%. (author)

  5. Safety Analysis for Power Reactor Protection System

    International Nuclear Information System (INIS)

    The main function of a Reactor Protection System (RPS) is to safely shutdown the reactor and prevents the release of radioactive materials. The purpose of this paper is to present a technique and its application for used in the analysis of safety system of the Nuclear Power Plant (NPP). A more advanced technique has been presented to accurately study such problems as the plant availability assessments and Technical Specifications evaluations that are becoming increasingly important. The paper provides the Markov model for the Reactor Protection System of the NPP and presents results of model evaluations for two testing policies in technical specifications. The quantification of the Markov model provides the probability values that the system will occupy each of the possible states as a function of time.

  6. Regulatory System of Radiation Protection in Taiwan

    International Nuclear Information System (INIS)

    After the radioactive contaminated buildings incident occurred in Taiwan in 1993, the competent authority for radiation protection the Atomic Energy Council (AEC) started to review the structured problem of radiation protection regulatory system. Through several years' investigation and study, the AEC has improved two important tools in radiation protection regulatory system, i.e., control regulations and actual practice, and made them more rigorous and efficient. This paper will make a brief introduction of the efforts that Taiwan has made in this respect. Taiwan's radiation protection control was based on the Atomic Energy Law promulgated in 1968, but the control idea and authorization scope were not sufficient to appropriately respond to the highly developed economy and democracy in Taiwan. After several years' legislative process, the Ionizing Radiation Protection Law (IRP Law) was promulgated and entered into force on February 1, 2003. This IRP Law specifically emphasizes categorized risk management of radiation sources, establishment of personnel licenses and training system, enhancement of public safety control, and implementation of quality assurance program for medical exposure. The Legislative Yuan (Congress) fully authorized the competent authority to establish various technological control regulations according to control necessity without prior review by the Legislative Yuan in advance. As to the penalties of the violations of the IRP Law, the AEC adopts high-rated administrative fines and applies the Criminal Law to those who seriously contaminate the environment. In actual practice, the AEC has constructed a Radiation Protection Control Information System compatible with the IRP Law that fully combines the functions of computers and Internet. The information of facility operators who own radiation sources, radiation protection specialists, and operating personnel are entered into this system, starting from the submission of application of the

  7. Fire protection countermeasures for containment ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Alvares, N.J.; Beason, D.G.; Bergman, W.; Ford, H.W.; Lipska, A.E.

    1980-01-01

    The goal of this project is to find countermeasures to protect HEPA filters in exit ventilation ducts from the heat and smoke generated by fire. Several methods for partially mitigating the smoke exposure to the HEPA filters were identified through testing and analysis. These independently involve controlling the fuel, controlling the fire, and intercepting the smoke aerosol prior to its sorption on the HEPA filter. Exit duct treatment of aerosols is not unusual in industrial applications and involves the use of scrubbers, prefilters, and inertial impaction, depending on the size, distribution, and concentration of the subject aerosol. However, when these unmodified techniques were applied to smoke aerosols from fires on materials, common to experimental laboratories of LLNL, it was found they offered minimal protection to the HEPA filters. Ultimately, a continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. This technique is capable of protecting HEPA filters over the total duration of the test fires. The reason for success involved the modificaton of the prefiltration media. Commercially available filter media has a particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, we laminated rolling filter media with the desired properties. It is not true that the use of rolling prefilters solely to protect HEPA filters from fire-generated smoke aerosols is cost effective in every type of containment system, especially if standard fire-protection systems are available in the space. But in areas of high fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified.

  8. Fire protection countermeasures for containment ventilation systems

    International Nuclear Information System (INIS)

    The goal of this project is to find countermeasures to protect HEPA filters in exit ventilation ducts from the heat and smoke generated by fire. Several methods for partially mitigating the smoke exposure to the HEPA filters were identified through testing and analysis. These independently involve controlling the fuel, controlling the fire, and intercepting the smoke aerosol prior to its sorption on the HEPA filter. Exit duct treatment of aerosols is not unusual in industrial applications and involves the use of scrubbers, prefilters, and inertial impaction, depending on the size, distribution, and concentration of the subject aerosol. However, when these unmodified techniques were applied to smoke aerosols from fires on materials, common to experimental laboratories of LLNL, it was found they offered minimal protection to the HEPA filters. Ultimately, a continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. This technique is capable of protecting HEPA filters over the total duration of the test fires. The reason for success involved the modificaton of the prefiltration media. Commercially available filter media has a particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, we laminated rolling filter media with the desired properties. It is not true that the use of rolling prefilters solely to protect HEPA filters from fire-generated smoke aerosols is cost effective in every type of containment system, especially if standard fire-protection systems are available in the space. But in areas of high fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  9. Expert systems for protective monitoring of facilities

    International Nuclear Information System (INIS)

    In complex plants, the possibility of serious operator error always exists to some extent, but, this can be especially true during an experiment or some other unusual exercise. Possible contributing factors to operational error include personnel fatigue, misunderstanding in communication, mistakes in executing orders, uncertainty about the delegated authority, pressure to meet a demanding schedule, and a lack of understanding of the possible consequences of deliberate violations of the facility's established operating procedures. Authoritative reports indicate that most of these factors were involved in the disastrous Russian Chernobyl-4 nuclear reactor accident in April 1986, which, ironically, occurred when a safety experiment was being conducted. Given the computer hardware and software now available for implementing expert systems together with integrated signal monitoring and communications, plant protection could be enhanced by an expert system with extended features to monitor the plant. The system could require information from the operators on a rigidly enforced schedule and automatically log in and report on a scheduled time basis to authorities at a central remote site during periods of safe operation. Additionally, the system could warn an operator or automatically shut down the plant in case of dangerous conditions, while simultaneously notifying independent, responsible, off-site personnel of the action taken. This approach would provide protection beyond that provided by typical facility scram circuits. This paper presents such an approach to implementing an expert system for plant protection, together with specific hardware and software configurations. The Chernobyl accident is used as the basis of discussion

  10. Tantalum oxide nanocoatings prepared by atomic layer and filtered cathodic arc deposition for corrosion protection of steel: Comparative surface and electrochemical analysis

    International Nuclear Information System (INIS)

    Highlights: ► 50 nm Ta2O5 coatings grown by ALD at 160 °C and FCAD for protection of steel. ► Combined analysis by ToF-SIMS, XPS, polarization curves and EIS. ► Relation between chemical architecture and corrosion protection properties studied. ► Localized corrosion by pitting with absence of coating dissolution demonstrated. ► Origin and role of spurious interfacial oxide promoting coating breakdown emphasized. -- Abstract: A comparative study by Time-of-Flight Secondary Ions Mass Spectrometry and X-ray Photoelectron Spectroscopy, i–E polarization curves and Electrochemical Impedance Spectroscopy of the corrosion protection of low alloy steel by 50 nm thick tantalum oxide coatings prepared by low temperature Atomic Layer Deposition (ALD) and Filtered Cathodic Arc Deposition (FCAD) is reported. The data evidence the presence of a spurious oxide layer mostly consisting of iron grown by transient thermal oxidation at the ALD film/substrate interface in the initial stages of deposition and its suppression by pre-treatment in the FCAD process. Carbonaceous contamination (organic and carbidic) resulting from incomplete removal of the organic precursor is the major cause of the poorer sealing properties of the ALD film. No coating dissolution is demonstrated in neutral or acid 0.2 M NaCl solutions. In acid solution localized corrosion by pitting proceeds faster with the ALD than with the FCAD coating. The roles of the pre-existing channel defects exposing the substrate surface and of the spurious interfacial oxide promoting coating breakdown and/or delamination are emphasized

  11. Fire protection countermeasures for containment ventilation systems

    International Nuclear Information System (INIS)

    The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in the total spectrum of containment systems, especially if standard fire protection systems are available in the space. But in areas of high-fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified

  12. Fire protection countermeasures for containment ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Alvares, N.; Beason, D.; Bergman, V.; Creighton, J.; Ford, H.; Lipska, A.

    1980-08-25

    The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in the total spectrum of containment systems, especially if standard fire protection systems are available in the space. But in areas of high-fire risk, where the potential fuel load is large and ignition sources are plentiful, the complication of a rolling prefilter in exit ventilation ducts to protect HEPA filters from smoke aerosols is definitely justified.

  13. Crystalline TiO2: A Generic and Effective Electron-Conducting Protection Layer for Photoanodes and -cathodes

    DEFF Research Database (Denmark)

    Mei, Bastian Timo; Pedersen, Thomas; Malacrida, Paolo;

    2015-01-01

    shows that under certain conditions n-type semiconductors, such as TiO2, can be used as protection layers for Si-based photoanodes. It also provides evidence that even in a photoanode assembly TiO2 is conducting only electrons (not holes as in p-type protection layers), and therefore TiO2 can be...... described as a simple ohmic contact. This renders n-type semiconductors, such as TiO2, to be versatile and simple protection layers, which can be used for photoanodes and as previously shown for photocathodes. The ohmic behavior of n-type TiO2 in a Si/TiO2-photoanode assembly is demonstrated under dark and...... illuminated conditions by performing the oxygen evolution reaction (OER) and using the Fe(II)/Fe(III) redox couple. These measurements reveal that the performance of the Si/TiO2-photoanode assembly is strongly dependent on the TiO2/electrolyte interaction. Finally, the conditions and requirements that make Ti...

  14. System Protection Schemes in Eastern Denmark

    OpenAIRE

    Rasmussen, Joana; Rønne-Hansen, Jan; Nielsen, Arne Hejde; Jørgensen, Preben; Havsager, Jan

    2006-01-01

    The Ph.D. project investigates different aspects of voltage stability in the power system ofEastern Denmark taking into account the large amount of wind power. In the project, a simpleSystem Protection Scheme (SPS) against voltage instability in Eastern Denmark is developed.The SPS design is based on static and dynamic simulation analyses using a large-scale model1that considers a number of realistic power system conditions. The southern part of the 132-kVsystem is prone to voltage stability ...

  15. Cathode materials review

    International Nuclear Information System (INIS)

    The electrochemical potential of cathode materials defines the positive side of the terminal voltage of a battery. Traditionally, cathode materials are the energy-limiting or voltage-limiting electrode. One of the first electrochemical batteries, the voltaic pile invented by Alessandro Volta in 1800 (Phil. Trans. Roy. Soc. 90, 403-431) had a copper-zinc galvanic element with a terminal voltage of 0.76 V. Since then, the research community has increased capacity and voltage for primary (nonrechargeable) batteries and round-trip efficiency for secondary (rechargeable) batteries. Successful secondary batteries have been the lead-acid with a lead oxide cathode and a terminal voltage of 2.1 V and later the NiCd with a nickel(III) oxide-hydroxide cathode and a 1.2 V terminal voltage. The relatively low voltage of those aqueous systems and the low round-trip efficiency due to activation energies in the conversion reactions limited their use. In 1976, Wittingham (J. Electrochem. Soc., 123, 315) and Besenhard (J. Power Sources 1(3), 267) finally enabled highly reversible redox reactions by intercalation of lithium ions instead of by chemical conversion. In 1980, Goodenough and Mizushima (Mater. Res. Bull. 15, 783-789) demonstrated a high-energy and high-power LiCoO2 cathode, allowing for an increase of terminal voltage far beyond 3 V. Over the past four decades, the international research community has further developed cathode materials of many varieties. Current state-of-the-art cathodes demonstrate voltages beyond any known electrolyte stability window, bringing electrolyte research once again to the forefront of battery research

  16. Distribution system protection with communication technologies

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    power system, including CHPs (Combined Heating and Power) and small scaled WTs (Wind Turbines), as a practical example to examine the possible impacts of communication technologies on the power system. Under some fault scenarios, the power system’s responses to the fault are compared between the system......Due to the communication technologies’ involvement in the distribution power system, the time-critical protection function may be implemented more accurately, therefore distribution power systems’ stability, reliability and security could be improved. This paper presents an active distribution...... with communication technologies and that without communication technologies. At the same time, the previously proposed study method of combining the simulations of communication and power systems is adopted in this study. The performance of a communication network adopted for power system is simulated...

  17. Protection of LV system against lightning

    OpenAIRE

    Yordanova Nedyalkova, Greta

    2010-01-01

    Lightning is a natural hazard and one of the greatest local mysteries. Scientists have not fully understood the mechanism of lightning. It is one of the most beautiful displays in nature and one of the nature's most dangerous phenomenon known to man. Overvoltage due to lightning is a very important problem of LV systems. Some lightning flashes damage buildings and a few kill or injure people and animals, either directly or indirectly, by causing fire and explosions. The need for protect...

  18. Lightning protection system for a wind turbine

    Science.gov (United States)

    Costin, Daniel P.; Petter, Jeffrey K.

    2008-05-27

    In a wind turbine (104, 500, 704) having a plurality of blades (132, 404, 516, 744) and a blade rotor hub (120, 712), a lightning protection system (100, 504, 700) for conducting lightning strikes to any one of the blades and the region surrounding the blade hub along a path around the blade hub and critical components of the wind turbine, such as the generator (112, 716), gearbox (708) and main turbine bearings (176, 724).

  19. Halon 1301 protection system for nuclear containments

    International Nuclear Information System (INIS)

    Halon 1301 can provide protection against any combustion hazard that hydrogen gas might present in an LWR containment following a loss-of-coolant accident. A development program was conducted, comprising analytical study, laboratory experiments and large-scale testing, to define the requirements for a Halon 1301 system and to examine certain operational problems that were hypothesized. Some results of the study are presented in this paper

  20. Achieving Sustainable and Effective Physical Protection Systems

    International Nuclear Information System (INIS)

    We as the regulator also determine the graded approach to be adopted by the civil nuclear industry in protecting nuclear facilities and nuclear material against sabotage, as well as in protecting — sensitive nuclear information, and — computer systems important to safety and physical protection the compromise of which could assist adversaries in carrying out an act of theft or sabotage. UK security regulations require operators of civil licensed nuclear sites that hold Category I to IV nuclear material or other radioactive material, or those who use or store Category I to III nuclear material at other premises, to have a Security Plan approved by ONR. If a civil licensed nuclear site has a tenant(s) who uses, or stores nuclear or other radioactive material (including radioactive sources), then the tenant must have their own Security Plan. Our Nuclear Site Security Plans describe the standards, procedures and arrangements that enable Duty Holders to maintain acceptable and robust security arrangements at civil licensed nuclear sites and other nuclear premises. There are two parts to the plans: the Nuclear Security Case and the Integrated Protection Solution

  1. Enhanced personal protection system for the PS

    CERN Multimedia

    Caroline Duc

    2013-01-01

    During the first long shutdown (LS1) a new safety system will be installed in the primary beam areas of the PS complex in order to bring the standard of personnel radiation protection at the PS into line with that of the LHC.   Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system. The LHC access control systems are state-of-the-art, whereas those of the injection chain accelerators were running the risk of becoming obsolete. For the past two years a project to upgrade the access and safety systems of the first links in the LHC accelerator chain has been underway to bring them into compliance with nuclear safety standards. These systems provide the personnel with automatic protection by limiting access to hazardous areas and by ensuring that nobody is present in the areas when the accelerator is in operation. By the end of 2013, the project teams will ha...

  2. 阴极保护下缝隙内的电流分布%CURRENT DISTRIBUTION IN A CATHODICALLY PROTECTED CREVICE

    Institute of Scientific and Technical Information of China (English)

    李正奉; 毛旭辉; 甘复兴

    2000-01-01

    Current distributions in a cathodically protected crevice between a simulated coating andsegmented mild steel electrodes were measured in diluted NaCl solutions. The effects of the controlpotential, solution conductivity and crevice thickness on the current distribution were studied. Theresults showed that the current distribution inside the crevice became uniform with prolonging ofpolarization time. In general, the more negative the control potential, the greater the solutionconductivity and crevice thickness, the larger the current density inside the crevice.%采用分段碳钢电极测量了稀NaCl溶液中阴极保护下模拟缝隙内的电流分布,研究了缝口控制电位、溶液电导率和缝隙宽度对电流分布的影响.结果表明在实验条件下缝隙内的电流分布随极化时间的延长而趋于均匀.溶液电导率和缝隙宽度的增大以及缝口控制电位的负移都可使缝隙内局部电流增大,阴极保护深度增大.

  3. Distance Protection of Cross-Bonded Transmission Cable-Systems

    DEFF Research Database (Denmark)

    Bak, Claus Leth; F. Jensen, Christian

    2014-01-01

    systems are being laid around the world. Differential protection is often used for the main protection of cables. As a backup protection, distance protection is very often the preferred choice. Therefore, the behaviour of distance protection when applied to cross-bonded cablesystems is very interesting....

  4. River Protection Project information systems assessment

    International Nuclear Information System (INIS)

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report

  5. River Protection Project information systems assessment; FINAL

    International Nuclear Information System (INIS)

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report

  6. River Protection Project information systems assessment

    Energy Technology Data Exchange (ETDEWEB)

    JOHNSON, A.L.

    1999-07-28

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report.

  7. A New Photocatalytic System Using Steel Mesh and Cold Cathode Fluorescent Light for the Decolorization of Azo Dye Orange G

    OpenAIRE

    Ming-Chin Chang; Chin-Pao Huang; Hung-Yee Shu; Yung-Chen Chang

    2012-01-01

    High color and organic composition, the effluents from the textile dyeing and finishing industry, can be treated by photocatalytic oxidation with UV/TiO2. The objective of this study was to prepare a new photocatalytic system by coating nanosized TiO2 particles on steel mesh support and using cold cathode fluorescent light (CCFL) irradiation at 365 nm in a closed reactor for the oxidation of azo dye C.I. Orange G (OG). Various factors such as reaction time, coating temperature, TiO2 dosage, p...

  8. A photoelectrochemical study of CdS modified TiO2 nanotube arrays as photoanodes for cathodic protection of stainless steel

    International Nuclear Information System (INIS)

    An electrodeposited CdS nanoparticles-modified highly-ordered TiO2 nanotube arrays (CdS-TNs) photoelectrode and its performance of photocathodic protection are reported. The self-organized TiO2 nanotube arrays are fabricated by electrochemical anodization in an organic-inorganic mixed electrolyte and sensitized with CdS nanoparticles by electrodeposition via a single-step direct current. The morphology, crystalline phase, and composition of the CdS-TNs films were characterized systematically by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and ultraviolet-visible (UV-Vis) spectroscopy, respectively. The photoelectrochemical performances of the CdS-TNs film under illumination and dark conditions in 0.5 M NaCl solution were evaluated through the electrochemical measurements. It is indicated that the TNs incorporated by CdS effectively harvest solar light in the UV as well as the visible light (up to 480 nm) region. It is supposed that the high photoelectro-response activity of the CdS-TNs is attributed to the increased efficiency of charge separation and transport of electrons. The electrode potentials of 304 stainless steel coupled with the CdS-TNs is found to be negatively shifted for about 246 mV and 215 mV under UV and white light irradiation, respectively, which can be remained for 24 h even in darkness. It is implied that the CdS-TNs are able to effectively function a photogenerated cathodic protection for metals both under the UV and visible light illumination.

  9. Model of Physical Protection System for Nuclear Material and Facility

    International Nuclear Information System (INIS)

    Physical Protection System Nuclear for nuclear materials and facilities are pursuant to the regulation No. 27/2002. The guide of nuclear facility and protection physic and suggest from IPPAS. The direction of nuclear facility and protection physic is to protect from sabotage, terrorism, espionage subversive and the moving of nuclear object in a illegal manner (stealing). To have the direction of nuclear facility and protection physic we need to detect, value, response, wait and stop it from the intimidation. According to all about that, so we need to design a model of nuclear facility and protection physic system, consist of Design Basis Threat modeling (DBT), soft system modeling, hard system modeling, analysis system and instrument of nuclear facility and protection physic system. Each model entity that system, next we make a model of nuclear facility and protection physic system completely, to make it easy to understand, to learn, to design that installation, socialization and implementation of nuclear facility and protection physic system

  10. New fire protection concept for computer systems

    International Nuclear Information System (INIS)

    As the term clearly suggests, electronic data processing systems are collection points for all kinds of data requiring processing and analysis. They are also, as a rule, vitally important centres for the development of industrial products or - most conspicuously in the case of nuclear power plants - process control. The failure of a central computer or a central control room leads to considerable material damages, with far reaching repercussions for production and warehouse storage (availability), as various fires and loss scenarios have shown. The fire protection concepts elaborated hitherto for large and small computer installations, particularly in process control, have not proved satisfactory. Wet and pre-action sprinkler installations, CO2 and halon total flooding systems have certain advantages, assuming that 'protection' of computer installations or control units really does occur, but also many disadvantages. Owing to the difficulty of determining the reliability of air currents, fire alarms often require a response time of 20 to 40 minutes. This results in massive smoke development and considerable corrosion damage, as a fire at a nuclear power plant a few months ago once again illustrated. In an extensive series of fire and extinguishing tests carried out in the test facility at the Allianz Centre for Technology, the Allianz Brandschutz Service demonstrated that with local application systems (i.e. equipment specific detectors and integrated extinguishing systems), fires can be detected and put out more rapidly and selectively with lower overall investment and loss expenditure and only minimal partial outage. The tests also showed that it is possible to extinguish fires in electrical and electronic equipment, or that these can be flooded, without causing additional damage through a sudden drop in temperature ('cold shock'). In addition, in not using halon total flooding systems, an important contribution to environmental protection is made, since the

  11. The run permit protection system for GTA

    International Nuclear Information System (INIS)

    A Run Permit system has been designed for the Ground Test Accelerator (GTA). The system implements mode-dependent software interlocks to ensure proper operation of the accelerator, enabling the ion source extractor and RF systems when proper conditions are met. The system is implemented using the GTA control system; thus all information available to the control system is also available for use in interlock logic. The logic is defined in terms of control system channels, which reflect accelerator parameters such as actuator positions, power supply values, temperatures, etc. A mode switch in the control room selects the accelerator operating mode, for example injector only. The Run Permit software selects interlock logic as appropriate operating mode. This implementation easily accommodates logic changes as requirements evolve. To ensure reliable operation of a software-based system, a special circuit with a watch-dog timer is employed to produce the system's output signals. The software must periodically address the circuit, or the output signals are forced to a disabled state. For additional protection, there are self-test provisions for detecting and reacting to failures of the control system. (Author) 4 figs., ref

  12. Radiological protection national system. Basic security rules

    International Nuclear Information System (INIS)

    This work has been prepared as the first one of a set of standards and regulations that will be enforced to provide the protection of men and the environment against the undesirable effects of ionizing radiations. It establishes, in the first place, the system of dose limits for the country and the principles of its utilization. It takes into account the CIPR's recommendations in this area and the mentioned frame of reference, it establishes further the necessary restrictions for the application of the limits to the professionally exposed workers, as well as to the isolated members of the public and the population in general. In addition it establishes the general conditions to be met for the implementation of radiological protection, among them, the classification of working areas and working conditions as well as the compulsory periodical medical surveillance. (H.D.N.)

  13. Strategic Investment in Protection in Networked Systems

    CERN Document Server

    Leduc, Matt V

    2015-01-01

    We study the incentives that agents have to invest in costly protection against cascading failures in networked systems. Applications include vaccination, computer security and airport security. Agents are connected through a network and can fail either intrinsically or as a result of the failure of a subset of their neighbors. We characterize the equilibrium based on an agent's failure probability and derive conditions under which equilibrium strategies are monotone in degree (i.e. in how connected an agent is on the network). We show that different kinds of applications (e.g. vaccination, airport security) lead to very different equilibrium patterns of investments in protection, with important welfare and risk implications. Our equilibrium concept is flexible enough to allow for comparative statics in terms of network properties and we show that it is also robust to the introduction of global externalities (e.g. price feedback, congestion).

  14. National Ignition Facility environmental protection systems

    International Nuclear Information System (INIS)

    The conceptual design of Environmental Protection Systems (EPS) for the National Ignition Facility (NIF) is described. These systems encompass tritium and activated debris handling, chamber, debris shield and general decontamination, neutron and gamma monitoring, and radioactive, hazardous and mixed waste handling. Key performance specifications met by EPS designs include limiting the tritium inventory to 300 Ci and total tritium release from NIF facilities to less than 10 Ci/yr. Total radiation doses attributable to NIF shall remain below 10 mrem/yr for any member of the general public and 500 mrem/yr for NIF staff. ALARA-based design features and operational procedures will, in most cases, result in much lower measured exposures. Waste minimization, improved cycle time and reduced exposures all result from the proposed CO2 robotic arm cleaning and decontamination system, while effective tritium control is achieved through a modern system design based on double containment and the proven detritiation technology

  15. Radiological protection system in the era of nuclear renaissance expectation for development of radiological protection system

    International Nuclear Information System (INIS)

    The current radiological protection system, which was established mainly by the ICRP and UNSCEAR, has contributed to the prevention of potential radiological health hazards, and has been a fundamental concept during the development of nuclear energy. Through a detailed discussion regarding the new ICRP recommendations, the world nuclear industry has reached a consensus that the current radiological protection system keeps its integrity in principle although it involves some remaining issues, such as the disposal of radioactive waste. In order to maximize the advantages of nuclear energy while keeping the integrity of radiological protection system, it is essential to address the characteristics of radiation, which is specific to nuclear energy, so that nuclear energy can coexist with other energy sources. The three basic principles of radiological protection (i.e., justification, optimization and dose limits), which were completed in the 1990 recommendations of ICRP, should be retained as the basic concepts for the future radiological protection system in order to maintain the continuity and consistency of the radiological protection system. The radiological protection system can be furthermore developed only by combining the above three principles with best practices extracted from utilities' field experience. The significant reduction of radiation exposures received by members of the public and radiation workers in the field has resulted from the efforts by the world utilities to achieve the optimization. In order to correctly apply the theory to the work practices, it is essential to see how the theory is practically used in the field. Such a process should be also emphasized in the revision work of the IAEA Basic Safety Standards (BSS), which is currently under progress. Integrating the theory in the work practices is the key to the true development of nuclear renaissance, which could lead to the establishment of the nuclear safety regime. (author)

  16. 75 FR 81152 - Interpretation of Protection System Reliability Standard

    Science.gov (United States)

    2010-12-27

    ...? (i.e., transformer sudden pressure relays).'' Response: ``The existing definition of `Protection... reliability of the Bulk-Power System should be included as a component of a Protection System. Accordingly, to... maintenance and testing of Protection Systems affecting the reliability of the Bulk-Power System. 13....

  17. TREAT Reactor Control and Protection System

    International Nuclear Information System (INIS)

    The main control algorithm of the Transient Reactor Test Facility (TREAT) Automatic Reactor Control System (ARCS) resides in Read Only Memory (ROM) and only experiment specific parameters are input via keyboard entry. Prior to executing an experiment, the software and hardware of the control computer is tested by a closed loop real-time simulation. Two computers with parallel processing are used for the reactor simulation and another computer is used for simulation of the control rod system. A monitor computer, used as a redundant diverse reactor protection channel, uses more conservative setpoints and reduces challenges to the Reactor Trip System (RTS). The RTS consists of triplicated hardwired channels with one out of three logic. The RTS is automatically tested by a digital Dedicated Microprocessor Tester (DMT) prior to the execution of an experiment. 6 refs., 5 figs., 1 tab

  18. Ion current to a substrate in the pulsed dc hollow cathode plasma jet deposition system

    Czech Academy of Sciences Publication Activity Database

    Virostko, Petr; Hubička, Zdeněk; Čada, Martin; Tichý, M.

    2010-01-01

    Roč. 43, č. 12 (2010), s. 1-7. ISSN 0022-3727 R&D Projects: GA AV ČR KAN301370701; GA ČR GP202/09/P159; GA ČR GA202/09/0800 Grant ostatní: AVČR(CZ) M100100915 Institutional research plan: CEZ:AV0Z10100522 Keywords : plasma * pulsed DC * ion flux * hollow cathode Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.105, year: 2010 http://stacks.iop.org/JPhysD/43/124019

  19. Selectivity of power system protections at power swings in power system

    OpenAIRE

    Jan Machowski

    2012-01-01

    The paper discusses out-of-step protection systems such as: generator pole slip protections, out of step tripping protections, distance protections of step-up transformer, distance protections of transmission lines and transformers, power swing blocking, and special out-of-step protection. It is shown that all these protections make up a protection system, to which a setting concept uniform for the entire power system has to be applied. If a power system is inappropriately equipped with th...

  20. 酸性土壤中接地网牺牲阳极阴极保护法研究%Galvanic Anode Cathodic Protection of Grounding Grid in Acidic Soils

    Institute of Scientific and Technical Information of China (English)

    杜鹏; 刘欣; 郜友彬; 李多生; 裴锋; 刘光明; 田旭; 蒋磊

    2015-01-01

    Objective To improve the corrosion resistance of galvanic anode cathodic protection for grounding grid in acidic soil, analyze key technologies of the application of galvanic anode cathodic protection method in acid soil and summarize measures for improving the protection effect. Methods The designed simulated expendable anode system was applied to widely investigate grounding resistance, protection potential and protection current of Q235 steel and galvanized steel with 3. 52 m2 grounding grid and 35. 2 mA protection current. Results Galvanized steel was well protected and the protective potential was lower than-0. 95 V. But the protection of Q235 steel was less effective, and the protective potential exceeded -750 mV with fluctuation of 210 mV some-times. During the operation, the protective current could reach 30. 75 mA when the precipitation was high, and was reduced to 11. 89 mA when the precipitation was low, both of which were lower than the design values. Conclusion This was mainly due to high soil resistivity in the anode environment, more gravel resulted in less anode current. Second, poor soil water retention, resist-ance fluctuations, and unstable systems also decreased the protective effect. The salinity of acidic soil was greatly lost. The soil re-sistivity was high and disturbed by rainfall, so the work efficiency and stability were limited. Protection current was improved by measures such as reasonable increase of protection current, reduction of soil resistivity in the anode environment, and optimization of anode design process parameters.%目的:提高牺牲阳极的阴极保护法在酸性土壤中对接地网的防腐能力,分析牺牲阳极阴极保护法在酸性土壤中应用的技术要点,总结保护效果优化措施。方法设计牺牲阳极模拟系统,模拟地网面积为3.52 m2,保护电流设计为35.2 mA,对Q235碳钢和镀锌钢两种常用接地材料的接地电阻、保护电位及保护电流进行研究。结果该方

  1. Privacy protection schemes for fingerprint recognition systems

    Science.gov (United States)

    Marasco, Emanuela; Cukic, Bojan

    2015-05-01

    The deployment of fingerprint recognition systems has always raised concerns related to personal privacy. A fingerprint is permanently associated with an individual and, generally, it cannot be reset if compromised in one application. Given that fingerprints are not a secret, potential misuses besides personal recognition represent privacy threats and may lead to public distrust. Privacy mechanisms control access to personal information and limit the likelihood of intrusions. In this paper, image- and feature-level schemes for privacy protection in fingerprint recognition systems are reviewed. Storing only key features of a biometric signature can reduce the likelihood of biometric data being used for unintended purposes. In biometric cryptosystems and biometric-based key release, the biometric component verifies the identity of the user, while the cryptographic key protects the communication channel. Transformation-based approaches only a transformed version of the original biometric signature is stored. Different applications can use different transforms. Matching is performed in the transformed domain which enable the preservation of low error rates. Since such templates do not reveal information about individuals, they are referred to as cancelable templates. A compromised template can be re-issued using a different transform. At image-level, de-identification schemes can remove identifiers disclosed for objectives unrelated to the original purpose, while permitting other authorized uses of personal information. Fingerprint images can be de-identified by, for example, mixing fingerprints or removing gender signature. In both cases, degradation of matching performance is minimized.

  2. 3D Multifunctional Ablative Thermal Protection System

    Science.gov (United States)

    Feldman, Jay; Venkatapathy, Ethiraj; Wilkinson, Curt; Mercer, Ken

    2015-01-01

    NASA is developing the Orion spacecraft to carry astronauts farther into the solar system than ever before, with human exploration of Mars as its ultimate goal. One of the technologies required to enable this advanced, Apollo-shaped capsule is a 3-dimensional quartz fiber composite for the vehicle's compression pad. During its mission, the compression pad serves first as a structural component and later as an ablative heat shield, partially consumed on Earth re-entry. This presentation will summarize the development of a new 3D quartz cyanate ester composite material, 3-Dimensional Multifunctional Ablative Thermal Protection System (3D-MAT), designed to meet the mission requirements for the Orion compression pad. Manufacturing development, aerothermal (arc-jet) testing, structural performance, and the overall status of material development for the 2018 EM-1 flight test will be discussed.

  3. Lightweight Thermal Protection System for Atmospheric Entry

    Science.gov (United States)

    Stewart, David; Leiser, Daniel

    2007-01-01

    TUFROC (Toughened Uni-piece Fibrous Reinforced Oxidation-resistant Composite) has been developed as a new thermal protection system (TPS) material for wing leading edge and nose cap applications. The composite withstands temperatures up to 1,970 K, and consists of a toughened, high-temperature surface cap and a low-thermal-conductivity base, and is applicable to both sharp and blunt leading edge vehicles. This extends the possible application of fibrous insulation to the wing leading edge and/or nose cap on a hypersonic vehicle. The lightweight system comprises a treated carbonaceous cap composed of ROCCI (Refractory Oxidation-resistant Ceramic Carbon Insulation), which provides dimensional stability to the outer mold line, while the fibrous base material provides maximum thermal insulation for the vehicle structure.

  4. DISTRIBUTION FEEDER PROTECTION WITH AND WITHOUT PV SYSTEM

    OpenAIRE

    PADMAVATHY.P, PARTHASARATHY.S

    2013-01-01

    This paper deals with the enhanced fault analysis methodology enabling protection engineers to design a distribution protective system. This paper also deals with the determination of operating time of the protective devices on distribution feeder with and without photovoltaic systems along with the computation of fault current and its variation on using photovoltaic (PV) system.

  5. Polymer Electrolyte Fuel Cells Employing Heteropolyacids as Redox Mediators for Oxygen Reduction Reactions: Pt-Free Cathode Systems.

    Science.gov (United States)

    Matsui, Toshiaki; Morikawa, Eri; Nakada, Shintaro; Okanishi, Takeou; Muroyama, Hiroki; Hirao, Yoshifumi; Takahashi, Tsuyoshi; Eguchi, Koichi

    2016-07-20

    In this study, the heteropolyacids of H3+xPVxMO12-xO40 (x = 0, 2, and 3) were applied as redox mediators for the oxygen reduction reaction in polymer electrolyte fuel cells, of which the cathode is free from the usage of noble metals such as Pt/C. In this system, the electrochemical reduction of heteropolyacid over the carbon cathode and the subsequent reoxidation of the partially reduced heteropolyacid by exposure to the dissolved oxygen in the regenerator are important processes for continuous power generation. Thus, the redox properties of catholytes containing these heteropolyacids were investigated in detail. The substitution quantity of V in the heteropolyacid affected the onset reduction potential as well as the reduction current density, resulting in a difference in cell performance. The chemical composition of heteropolyacid also had a significant impact on the reoxidation property. Among the three compounds, H6PV3Mo9O40 was the most suitable redox mediator. Furthermore, the pH of the catholyte was found to be the crucial factor in determining the reoxidation rate of partially reduced heteropolyacid as well as cell performance. PMID:27348019

  6. Protection vs. false targets in series systems

    International Nuclear Information System (INIS)

    The paper analyses the optimal distribution of the defense resources between protecting the genuine system elements and deploying false elements (targets) in a series system, which is destroyed when any genuine element is destroyed. False and genuine elements cannot be distinguished by the attacker. We analyze a two-period game where the defender builds the defense in the first period, whereas the attacker attacks in the second period. Three cases are considered: the attacker attacks only one element, the attacker attacks all system elements, the attacker chooses the number of elements to attack that maximizes the overall system vulnerability. The probability of element destruction in the case of attack is defined as a contest function depending on the ratio of the defender's and attacker's effort and on a contest intensity parameter. The dependence of the minmax defense strategy (number of false elements) and the most harmful attack strategy (number of attacked elements) on the amount of resources available to the counterparts, on the number of genuine system elements and on the contest intensity is analyzed. Illustrative examples are presented

  7. Digital signal processing in power system protection and control

    CERN Document Server

    Rebizant, Waldemar; Wiszniewski, Andrzej

    2011-01-01

    Digital Signal Processing in Power System Protection and Control bridges the gap between the theory of protection and control and the practical applications of protection equipment. Understanding how protection functions is crucial not only for equipment developers and manufacturers, but also for their users who need to install, set and operate the protection devices in an appropriate manner. After introductory chapters related to protection technology and functions, Digital Signal Processing in Power System Protection and Control presents the digital algorithms for signal filtering, followed

  8. Testing time for Sizewell B digital protection system

    International Nuclear Information System (INIS)

    The reactor protection system for the UK's Sizewell B PWR consists of two independent systems. Both provide automatic trip when set points are reached and initiate engineered safety features to minimise the impact of a fault. The secondary protection system and primary protection system have been implemented using diverse technologies. The secondary protection system uses analogue trip units with Laddic voting logic. The primary protection system, however, uses a microprocessor system and will be the first software based protection system in the UK civil nuclear industry. The programme of testing will demonstrate the correct behaviour of the primary protection system. This includes factory or works tests, site tests and operation at site before fuel load. A programme of dynamic testing has also been included as an important element of this demonstration and is outlined in this article. (author)

  9. An Evolved System of Radiological Protection

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, M.

    2004-07-01

    The current system of radiological protection based on the Linear No-Threshold (LNT) hypothesis has greatly contributed to the minimization of doses received by workers and members of the public. However, it has brought about {sup r}adiophobia{sup a}mong people and waste of resources due to over-regulation, because the LNT implies that radiation is harmful no matter how small the dose is. The author reviewed the results of research on health effects of radiation including major epidemiological studies on radiation workers and found no clear evidence of deleterious health effects from radiation exposures below the current maximum dose limits (50 mSv/y for workers and 5 mSv/y for members of the public), which have been adopted worldwide in the second half of the 20th century. Now that the existence of bio-defensive mechanisms such as DNA repair, apoptosis and adaptive response are well recognized, the linearity assumption cannot be said to be ''scientific''. Evidences increasingly imply that there are threshold effects in risk of radiation. A concept of practical thresholds or virtually safe doses will have to be introduced into the new system of radiological protection in order to resolve the low dose issues. Practical thresholds may be defined as dose levels below which induction of detectable radiogenic cancers or hereditary effects are not expected. If any workers and members of the public do not gain benefits from being exposed, excepting intentional irradiation for medical purposes, their radiation exposures should be kept below practical thresholds. On the assumption that the current dose limits are below practical thresholds and with no radiation detriments, there is no need of justification and optimization (ALARA) principles for occupational and public exposures. Then the ethical issue of justification to allow benefit to society to offset radiation detriments to individuals can be resolved. And also the ethical issue of optimization to

  10. An Evolved System of Radiological Protection

    International Nuclear Information System (INIS)

    The current system of radiological protection based on the Linear No-Threshold (LNT) hypothesis has greatly contributed to the minimization of doses received by workers and members of the public. However, it has brought about radiophobiaamong people and waste of resources due to over-regulation, because the LNT implies that radiation is harmful no matter how small the dose is. The author reviewed the results of research on health effects of radiation including major epidemiological studies on radiation workers and found no clear evidence of deleterious health effects from radiation exposures below the current maximum dose limits (50 mSv/y for workers and 5 mSv/y for members of the public), which have been adopted worldwide in the second half of the 20th century. Now that the existence of bio-defensive mechanisms such as DNA repair, apoptosis and adaptive response are well recognized, the linearity assumption cannot be said to be scientific. Evidences increasingly imply that there are threshold effects in risk of radiation. A concept of practical thresholds or virtually safe doses will have to be introduced into the new system of radiological protection in order to resolve the low dose issues. Practical thresholds may be defined as dose levels below which induction of detectable radiogenic cancers or hereditary effects are not expected. If any workers and members of the public do not gain benefits from being exposed, excepting intentional irradiation for medical purposes, their radiation exposures should be kept below practical thresholds. On the assumption that the current dose limits are below practical thresholds and with no radiation detriments, there is no need of justification and optimization (ALARA) principles for occupational and public exposures. Then the ethical issue of justification to allow benefit to society to offset radiation detriments to individuals can be resolved. And also the ethical issue of optimization to exchange health or safety for

  11. Hydrogen plasma etching of silicon dioxide in a hollow cathode system

    International Nuclear Information System (INIS)

    Chemical etching of various materials has been observed when hydrogen plasmas are used in material processing. In the case of the deposition of diamond films the preferential etching of sp2 bonded carbon is considered to be of fundamental importance. A few papers have been published which have indicated that etching by hydrogen ions is different to that by hydrogen atoms. In this paper we describe the etching of silicon dioxide by hydrogen which was plasma-activated in a molybdenum-lined RF hollow cathode. The etch rate was seen to be thermally activated but decreased with increasing plasma power. The addition of a few percentage of helium increased the etch rate. The application of a - 50 V bias to the sample holder almost doubled the etch rate indicating the importance of ion bombardment for the chemical reaction. At high plasma powers and substrate temperatures in excess of 450 oC a thin molybdenum deposit was formed on the quartz samples.

  12. Development of Graphene-based novel cathode material in MES system

    DEFF Research Database (Denmark)

    Chen, Leifeng; Aryal, Nabin; Ammam, Fariza;

    2014-01-01

    .The graphene (GP) has outstanding electrical conductivity, extremely high specific surface area,mechanical robustness and flexibility, chemical inertness, and biocompatibility. These special properties ofGP can provide excellent opportunity to improve the performance of MES. Gram negative microorganisms like...... Sporomusa ovata (S.O) typically have a negative outer-surface charge. The graphene oxide (GO) is the acceptor of the electron. If the GO accept electrons from the Sporomusa ovata and the GO can be reduced to graphene. This will lead to in situ construction of a bacteria/graphene network in the cathode. This...... characterizedand analyzed by SEM or AFM. Thanks to the high surface area for graphene, superior conductivity, biocompatibility, the incorporation of the large amount bacteria into the biofilm matrix, and forming multiplexed conductive pathways, so the hybrid biofilm can facilitate electron exchange between...

  13. Reactor protection system including engineered features actuation system

    International Nuclear Information System (INIS)

    The safety concept requires to ensure that - the reactor protection system - the active engineered safeguard - and the necessary auxiliary systems are so designed and interfaced in respect of design and mode of action that, in the event of single component failure reliable control of the consequences of accidents remains ensured at all times and that the availability of the power plant is not limited unnecessarily. In order to satisfy these requirements due, importance was attached to a consistent spacial separation of the mutually redundant subsystems of the active safety equipment. The design and layout of the reactor protection system, of the power supply (emergency power supply), and of the auxiliary systems important from the safety engineering point of view, are such that their subsystems also largely satisfy the requirements of independence and spacial separation. (orig./RW)

  14. Reliable Software Development for Machine Protection Systems

    CERN Document Server

    Anderson, D; Dragu, M; Fuchsberger, K; Garnier, JC; Gorzawski, AA; Koza, M; Krol, K; Misiowiec, K; Stamos, K; Zerlauth, M

    2014-01-01

    The Controls software for the Large Hadron Collider (LHC) at CERN, with more than 150 millions lines of code, resides amongst the largest known code bases in the world1. Industry has been applying Agile software engineering techniques for more than two decades now, and the advantages of these techniques can no longer be ignored to manage the code base for large projects within the accelerator community. Furthermore, CERN is a particular environment due to the high personnel turnover and manpower limitations, where applying Agile processes can improve both, the codebase management as well as its quality. This paper presents the successful application of the Agile software development process Scrum for machine protection systems at CERN, the quality standards and infrastructure introduced together with the Agile process as well as the challenges encountered to adapt it to the CERN environment.

  15. The international safeguards system and physical protection

    International Nuclear Information System (INIS)

    The report summarizes and explains facts and aspects of the IAEA safeguards performed within the framework of the Non-Proliferation Treaty, and shows perspectives to be discussed by the NPT Review Conferences in 1990 and 1995. The technical background of potential misuse of nuclear materials for military purposes is explained in connection with the physical protection regime of the international safeguards, referring to recent developments for improvement of technical measures for material containment and surveillance. Most attention is given to the peaceful uses of nuclear energy and their surveillance by the IAEA safeguards, including such new technologies and applications as controlled nuclear fusion, laser techniques for uranium enrichment, and particle accelerators. The report's concluding analyses of the current situation show potentials for improvement and desirable or necessary consequences to be drawn for the international safeguards system, also taking into account recent discussions on the parliamentary level. (orig./HP)

  16. Overview of the Orion Thermal Protection System

    Science.gov (United States)

    Kowal, T. John

    2010-01-01

    The Orion spacecraft is being developed as part of the Constellation Exploration Program and will serve as the United States crewed transportation system to the International Space Station after the retirement of the Space Shuttle in 2010 and as the eventual means to return U.S. astronauts to the Moon. Therefore, Orion is being designed for reentry missions from both low Earth orbit and from Lunar-return trajectories. This presentation will provide an overview of the development of the Orion TPS, a critical component in the development of the spacecraft. The thermal protection system (TPS) that protects the crew module from the extreme environments associated with Earth atmospheric reentry consists of a forward heatshield and an aft backshell. The requirements that drive the design of the TPS will be discussed, including several key requirements that establish a precedent for U.S. human-rated spacecraft. For the first time in U.S. human spaceflight, a vehicle s TPS is being designed with a specific, derived requirement for reliability. Also, due to the increased presence of spacecraft in Earth s orbit in recent decades, requirements for micro-meteoroid/orbital debris damage tolerance are also a driving requirement that has affected the selection of portions of the TPS. The efforts to select materials and to define a preliminary design for both the heatshield and the backshell will be described. This will include a discussion of the design challenges presented by the numerous penetrations on both the backshell and the heatshield. Finally, the verification and validation plan which is currently under development to certify the TPS for human-rated missions will be outlined. To support the execution of this plan, a ground test campaign for both thermal and structural performance is being designed. This test campaign will directly support thermal and thermal/structural analyses that also are fundamental to the certification effort.

  17. Force protection demining system (FPDS) detection subsystem

    Science.gov (United States)

    Zachery, Karen N.; Schultz, Gregory M.; Collins, Leslie M.

    2005-06-01

    This study describes the U.S. Army Force Protection Demining System (FPDS); a remotely-operated, multisensor platform developed for reliable detection and neutralization of both anti-tank and anti-personnel landmines. The ongoing development of the prototype multisensor detection subsystem is presented, which integrates an advanced electromagnetic pulsed-induction array and ground penetrating synthetic aperture radar array on a single standoff platform. The FPDS detection subsystem is mounted on a robotic rubber-tracked vehicle and incorporates an accurate and precise navigation/positioning module making it well suited for operation in varied and irregular terrains. Detection sensors are optimally configured to minimize interference without loss in sensitivity or performance. Mine lane test data acquired from the prototype sensors are processed to extract signal- and image-based features for automatic target recognition. Preliminary results using optimal feature and classifier selection indicate the potential of the system to achieve high probabilities of detection while minimizing false alarms. The FPDS detection software system also exploits modern multi-sensor data fusion algorithms to provide real-time detection and discrimination information to the user.

  18. Assessment of fire protection systems in proscenium theaters

    OpenAIRE

    Jaewook Kwon

    2014-01-01

    Stage fire protection measures, details differing from one region to another, have been established, codified and enforced throughout the world and have changed little over the past 100 years. Technological advancements in both stagecraft and fire protection systems have led to a need in the theater community to study the current state of theater fire protection requirements. The objective of the study was to assess the level of protection afforded by stage active fire protection measures, as...

  19. High Temperature Aerogels for Thermal Protection Systems

    Science.gov (United States)

    Hurwitz, Frances I.; Mbah, Godfrey C.

    2008-01-01

    High temperature aerogels in the Al2O3-SiO2 system are being investigated as possible constituents for lightweight integrated thermal protection system (TPS) designs for use in supersonic and hypersonic applications. Gels are synthesized from ethoxysilanes and AlCl3.6H2O, using an epoxide catalyst. The influence of Al:Si ratio, solvent, water to metal and water to alcohol ratios on aerogel composition, morphology, surface area, and pore size distribution were examined, and phase transformation on heat treatment characterized. Aerogels have been fabricated which maintain porous, fractal structures after brief exposures to 1000 C. Incorporation of nanofibers, infiltration of aerogels into SiC foams, use of polymers for crosslinking the aerogels, or combinations of these, offer potential for toughening and integration of TPS with composite structure. Woven fabric composites having Al2O3-SiO2 aerogels as a matrix also have been fabricated. Continuing work is focused on reduction in shrinkage and optimization of thermal and physical properties.

  20. The Interdependence between Social Protection System and Labour Market

    OpenAIRE

    Mihaela Cristina MOSTAVI

    2012-01-01

    The analysis of social policy impact over the labour market focuses on assessing the interdependence between the social protection system and the labour market, and performance of the social policies management, determinant factor in order to achieve simultaneous acceleration for social inclusion and social protection. The relationship of interdependence between the social protection system and the labour market was analysed through the main social protection, economic and social indicators a...

  1. Thermal Management and Thermal Protection Systems

    Science.gov (United States)

    Hasnain, Aqib

    2016-01-01

    's rays directly impinging on the system. Heating rate of the lamps were calculated by knowing fraction of emitted energy in a wavelength interval and the filament temperature. This version of the model can be used to predict performance of the system under vacuum with extreme cold or hot conditions. Initial testing of the PTMS showed promise, and the thermal math model predicts even better performance in thermal vacuum testing. ii) Thermal Protection Systems (TPS) are required for vehicles which enter earth's atmosphere to protect from aerodynamic heating caused by the friction between the vehicle and atmospheric gases. Orion's heat shield design has two aspects which needed to be analyzed thermally: i) a small excess of adhesive used to bond the outer AVCOAT layer to the inner composite structure tends to seep from under the AVCOAT and form a small bead in between two bricks of AVCOAT, ii) a silicone rubber with different thermophysical properties than AVCOAT fills the gap between two bricks of AVCOAT. I created a thermal model using TD to determine temperature differences that are caused by these two features. To prevent false results, all TD models must be verified against something known. In this case, the TD model was correlated to CHAR, an ablation modelling software used to analyze TPS. Analyzing a node far from the concerning features, we saw that the TD model data match CHAR data, verifying the TD model. Next, the temperature of the silicone rubber as well as the bead of adhesive were analyzed to determine if they exceeded allowable temperatures. It was determined that these two features do not have a significant effect on the max temperature of the heat shield. This model can be modified to check temperatures at various locations of the heat shield where the composite thickness varies.

  2. Rack Protection Monitor - A Simple System

    Energy Technology Data Exchange (ETDEWEB)

    Orr, S.

    1997-12-01

    The Rack Protection Monitor is a simple, fail-safe device to monitor smoke, temperature and ventilation sensors. It accepts inputs from redundant sensors and has a hardwired algorithm to prevent nuisance power trips due to random sensor failures. When a sensor is triggered the Rack Protection Monitor latches and annunicates the alarm. If another sensor is triggered, the Rack Protection Monitor locally shuts down the power to the relay rack and sends alarm to central control.

  3. 78 FR 77574 - Protection System Maintenance Reliability Standard

    Science.gov (United States)

    2013-12-24

    ... protection system, ``resulting in line relays being placed in service with the incorrect transformer ratio.... 824o (2012). \\2\\ Mandatory Reliability Standards for the Bulk Power System, Order No. 693, 72 FR 16,416... commissioning of power system protection systems.\\55\\ NERC commits in its Comments to keep the...

  4. StreamNet Query System: Protected Areas

    Data.gov (United States)

    Pacific States Marine Fisheries Commission — Beginning in 1983, the Northwest Power Planning Council (Council) directed extensive studies of existing habitat and has analyzed alternative means of protection....

  5. Evaluation results on the effectiveness of the corrosion protection system for underground pipelines, using the DC-voltage gradient technique

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Antonio Carlos [Petroquimica Uniao S.A., Santo Andre, SP (Brazil)

    2003-07-01

    A pipeline of diameter 6'' with 17.694 km of extension was evaluated how much to the integrity of its external covering and the effectiveness of the system of cathodic protection, using the method DC-Voltage Gradient. The Cathodic Protection in this pipeline is made by seven rectifiers. The gotten data indicate that the potential pipe-ground registered in some check points to the long one of the pipeline is extremely negative, what has led to a super protection of the pipeline for the CP. This if explains for the great proximity between the anodes and the pipeline. For km had been identified 917 failures with a mean density of 50,1 per Km. Beyond the analysis of the data, this work includes conclusions and recommendations detailed for the repairs of the covering of the pipeline and for improvement of the effectiveness of the CP. One sends regards to a combination of repairs in the covering and reevaluation of the CP, in way to improve the protection level and to assure the reduction of the risk of external corrosion. (author)

  6. Automatic counterfeit protection system code classification

    Science.gov (United States)

    Van Beusekom, Joost; Schreyer, Marco; Breuel, Thomas M.

    2010-01-01

    Wide availability of cheap high-quality printing techniques make document forgery an easy task that can easily be done by most people using standard computer and printing hardware. To prevent the use of color laser printers or color copiers for counterfeiting e.g. money or other valuable documents, many of these machines print Counterfeit Protection System (CPS) codes on the page. These small yellow dots encode information about the specific printer and allow the questioned document examiner in cooperation with the manufacturers to track down the printer that was used to generate the document. However, the access to the methods to decode the tracking dots pattern is restricted. The exact decoding of a tracking pattern is often not necessary, as tracking the pattern down to the printer class may be enough. In this paper we present a method that detects what CPS pattern class was used in a given document. This can be used to specify the printer class that the document was printed on. Evaluation proved an accuracy of up to 91%.

  7. Advanced materials for thermal protection system

    Science.gov (United States)

    Heng, Sangvavann; Sherman, Andrew J.

    1996-03-01

    Reticulated open-cell ceramic foams (both vitreous carbon and silicon carbide) and ceramic composites (SiC-based, both monolithic and fiber-reinforced) were evaluated as candidate materials for use in a heat shield sandwich panel design as an advanced thermal protection system (TPS) for unmanned single-use hypersonic reentry vehicles. These materials were fabricated by chemical vapor deposition/infiltration (CVD/CVI) and evaluated extensively for their mechanical, thermal, and erosion/ablation performance. In the TPS, the ceramic foams were used as a structural core providing thermal insulation and mechanical load distribution, while the ceramic composites were used as facesheets providing resistance to aerodynamic, shear, and erosive forces. Tensile, compressive, and shear strength, elastic and shear modulus, fracture toughness, Poisson's ratio, and thermal conductivity were measured for the ceramic foams, while arcjet testing was conducted on the ceramic composites at heat flux levels up to 5.90 MW/m2 (520 Btu/ft2ṡsec). Two prototype test articles were fabricated and subjected to arcjet testing at heat flux levels of 1.70-3.40 MW/m2 (150-300 Btu/ft2ṡsec) under simulated reentry trajectories.

  8. Reliability analysis of digital reactor protection system

    International Nuclear Information System (INIS)

    The reliability analysis of the digital reactor protection system (RPS) is an essential part in the probabilistic safety assessment (PSA) of the advanced boiling water reactor (ABWR). In this study, the reliability model and methodology were modified to evaluate the reliability of the digital RPS installed in the Japanese ABWR plant. The hardware failure rates in the foreign data source of digital components were applied, based on the similarity of the function of the digital components. The hardware failure rates of the digital components were estimated to range from 10-5 (/hr) to 10-7 (/hr), according to the types of the components. The software error events and their recovery factors in the design and fabrication stages were evaluated, considering the verification and validation process provided by the Japanese industry guideline. Then, the software failure probability of the programmable digital component was evaluated, utilizing the probability of software error events and their recovery factors. This probability was estimated to be 3.3 10-7 (/demand), which was about one order higher than that of our previous estimation. These models and results were applied to evaluate the reactor trip system (RTS) and the engineered safety feature (ESF) actuation system of the ABWR plant, both of which are the subsystems of the RPS. The unavailability of the digital RTS was estimated to be the mean value of 7.2 10-6 (/demand). If an alternate rod insertion (ARI) and a manual scram were considered, the unavailability was estimated to decrease to 1.6 10-9. The ECCS unavailability was estimated to be also nearly equal to the same values as the previous estimation, because the system unavailability was dominated by the unavailability of the mechanical components, such as pumps, valves, etc. The sensitivity analyses were conducted systematically, in order to evaluate the effect of the modeling uncertainty on the RTS unavailability. The results indicated that the unavailability

  9. Protective relaying of power systems using mathematical morphology

    CERN Document Server

    Wu, QH; Ji, TY

    2009-01-01

    Discusses the development of novel protective relaying algorithms, using Mathematical Morphology (MM). This book introduces the fundamental principles of MM, and brings together the applications of MM to develop different protective relaying algorithms for the protection of a variety of power system components.

  10. 49 CFR 179.18 - Thermal protection systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Thermal protection systems. 179.18 Section 179.18... Design Requirements § 179.18 Thermal protection systems. (a) Performance standard. When the regulations...) Systems that no longer require test verification. The Department maintains a list of thermal...

  11. 78 FR 44475 - Protection System Maintenance Reliability Standard

    Science.gov (United States)

    2013-07-24

    ... Standards for the Bulk Power System, Order No. 693, 72 FR 16,416 (April 4, 2007), FERC Stats. & Regs. ] 31... Energy Regulatory Commission 18 CFR Part 40 Protection System Maintenance Reliability Standard AGENCY..., PRC-005- 2--Protection System Maintenance, to supersede four existing Reliability Standards,...

  12. Tar-free epoxy/amine curing system for corrosion protection of ballast tanks

    International Nuclear Information System (INIS)

    Preservation of seawater ballast tanks is one of the biggest maintenance burdens. It is well known that coal tar is one of the best materials to protect steel substrates against marine corrosion and is also prevalently widely used in ship tanks so far. However if tar-containing paint is applied, it is harmful to health and especially dark color (black or brown) is only available, which makes uneasy to detect the defects of painting and rust. We have studied and developed a light color, modified amine cured epoxy coating system, which reveals perfect protection performance even though without tar for long-term service period. The coating system is less harmful to health as it does not contain coal tar materials and meets the stringent VOC regulation in view of its low content of organic solvent (SVR>80%). Experiments have been carried out on three kinds of substrates, shop-primed panels, blast-cleaned panels and pre-rusted panels. All test specimens were compared with commercialized tar containing epoxy coating on equivalently treated steel substrates. We will report the test results in laboratory, general anti-corrosion properties, adhesion properties and cathodic protection data from seawater cycle test and wave tank simulation device. And also the results being reported will include the survey for field applications

  13. Tidal wave protection control system; Tsunami bosai kanri system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-01-10

    Delivered by this company was a 'tidal wave protection station for Hamanaka-cho, Hokkaido' which is tidal wave disaster protection equipment. The features of the system is the 'easy-to-understand operation and watching by a table structure for each water gate and sluice' as well as its 'highly reliable communication system'. It receives a tidal wave warning from the weather satellite 'Himawari (sunflower)' upon the occurrence of an earthquake or tidal wave, notifying the occurrence to each place and calling a meeting at the town office. The gate operation is for watching the gate by means of CCTV (closed-circuit television), ensuring safety around the gate (water gate and sluice at 8 places), closing the gate, broadcasting the warning, etc., by remote control. In addition, it also carries out conservation of the operation history and video recording of the gate. Further, communication between the station and each water gate for example is such that the watching/control data and picture (animation and quasi-animation) data are transmitted by optical and radio communications (400MHz for the water gate system and SS (spectrum spreading) for the sluice system in radio). (translated by NEDO)

  14. Radiation protection system in Azerbaijan Republic

    International Nuclear Information System (INIS)

    land or merge into Caspian See. Is increased also the bring into country of instruments, equipments and other technical means, which work on radioactive sources basic. The numerated facts indicate that is necessary function of good radiation control land protection's system in Azerbaijan (sector radiation's investigations, Radioecology Center NMS of Ministry for Ecology and Natural Recourses the special Plant 'Isotope' and his burring point of radioactive wastes, Civil Defense. Academic organizations and NMS, execute monitoring, control and noticing function by radiation situation. The last two organizations structures, which have been occupied with keeping, transportation, disactivate and burring of radioactive sources and their wastes, which are receiving here from much institutions. The functional activity of special plant 'Isotope' must be reorganized and reconstruct- red the exist PBRW. There is necessity of build of new PBRW, in according with modern technical requirements to the industrial cycle on complete utilization of all radioactive wastes kinds. The monitoring function of radiation situation over all territory of Republic is put on NMS MENR of Azerbaijan. But, for the execution his problems, NMS are necessary new instrumental park (radiometric, dozemetric, spectrometric and etc.) and the dense monitoring network over all territory of Azerbaijan Republic. Co-operation with IAEA will allow improve the quality of radiation protection system of Azerbaijan in shorter periods. (author)

  15. Design and testing of a separate-type lighting system using solar energy and cold-cathode fluorescent lamps

    International Nuclear Information System (INIS)

    This paper presents a solar-powered lighting system, using cold-cathode fluorescent-lamps (CCFLs), with its battery-charging circuit and lamp-ignition circuit being separated so that its solar panels can be installed at any distance deemed necessary away from the lighting site in order to receive the maximum solar energy available. This system adopts the maximum-power point tracking (MPPT) method to control the power output of the solar panels and uses the zero-voltage switching (ZVS) DC-DC converter, as the charging circuit, to increase the panels' power generation efficiency and the charging circuit's conversion efficiency. The electronic ballast circuit for the CCFL is constructed with a half-bridge inverter, a resonant inductor, and a Rosen-type piezoelectric transformer, which forms a piezoelectric resonant-type inverter: to simplify the circuitry and to improve the power conversion efficiency, the ballast circuit is designed to directly step up the battery voltage in igniting the lamp. We also establish the transmission-parameter model for the piezoelectric resonant-type inverter to provide the base for the electric-power circuit design. Our experimental results indicate that the proposed system possesses some advantages, such as greater energy efficiency, circuitry simplicity, and so on, and is suitable for night lighting in house yards, parks and advertising panels

  16. Smart pigging - a contribution to the monitoring of the anti-corrosion protection systems on pig-inspectable high-pressure gas transmission pipelines; Intelligente Molchung - ein Beitrag zur Ueberwachung des Korrosionsschutzes molchbarer Gashochdruckleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, M.; Schoeneich, H.G. [Ruhrgas AG, Essen (Germany). Kompetenz-Center Korrosionsschutz

    2000-07-01

    High-pressure gas transmission pipelines installed underground are exposed to the risk of external corrosion. The application of a sheathing (passive protection) and, since the 1950s, the installation of a cathodic anti-corrosion protection system, provide pipelines with effective protection against this danger. In the past, the effectiveness of cathodic anti-corrosion protection systems was verified by means of intensive measuring and re-measuring cycles. It became apparent that points of damage to the sheathing were protected in the majority of cases against corrosion by the cathodic anti-corrosion protection system. There are, however, particular design circumstances and ambient conditions which can make this anti-corrosion protection concept either partially or completely ineffective. The use of smart pigs for inspection of pig-inspectable gas transmission pipelines makes it possible to detect and eliminate these weak points. (orig.) [German] Gashochdruckleitungen, die im Erdboden verlegt werden, unterliegen einer Gefaehrdung durch Aussenkorrosion. Durch eine Umhuellung (passiver Schutz) und seit den 50er Jahren durch die Einrichtung des kathodischen Korrosionsschutzes (aktiver Schutz) sind die Leitungen gegen diese Gefaehrdung wirkungsvoll geschuetzt. In der Vergangenheit wurde die Ueberpruefung der Wirksamkeit des kathodischen Korrosionsschutzes durch Intensivmessungen und Nachmessungen sichergestellt. Dabei zeigte sich, dass in der ueberwiegenden Zahl Umhuellungsbeschaedigungen durch den kathodischen Korrosionsschutz gegen Korrosion geschuetzt sind. Es gibt jedoch besondere konstruktive oder Umgebungsbedingungen, die dieses Korrosionsschuzkonzept teilweise oder vollstaendig unwirksam werden lassen. Mit dem Einsatz von intelligenten Molchen zur Inspektion molchbarer Gastransportleitungen koennen diese Schwachstellen erkannt und beseitigt werden. (orig.)

  17. Distributed systems for the protection of nuclear stations

    International Nuclear Information System (INIS)

    The advantages of distributed control systems usually mentioned are improved exploitation, cost reduction, and adaptation to changes in technology. These advantages are obviously very interesting for nuclear power plant applications, and many such systems have been proposed. This note comments on the application of the distributed system concept to protection systems - what should be distributed - and closes with a brief description of a protection system based on microprocessors for pressurized water stations being built in France. (auth)

  18. Power supply devices and systems of relay protection

    CERN Document Server

    Gurevich, Vladimir

    2013-01-01

    Power Supply Devices and Systems of Relay Protection brings relay protection and electrical power engineers a single, concentrated source of information on auxiliary power supply systems and devices. The book also tackles specific problems and solutions of relay protection power supply systems and devices, which are often not dealt with in the literature. The author, an experienced engineer with more than 100 patents, draws on his own experience to offer practical, tested advice to readers. A Guide to Relay Protection Power Supply for Engineers and Technicians The first chapter reviews the ele

  19. Novel Directional Protection Scheme for the FREEDM Smart Grid System

    Science.gov (United States)

    Sharma, Nitish

    This research primarily deals with the design and validation of the protection system for a large scale meshed distribution system. The large scale system simulation (LSSS) is a system level PSCAD model which is used to validate component models for different time-scale platforms, to provide a virtual testing platform for the Future Renewable Electric Energy Delivery and Management (FREEDM) system. It is also used to validate the cases of power system protection, renewable energy integration and storage, and load profiles. The protection of the FREEDM system against any abnormal condition is one of the important tasks. The addition of distributed generation and power electronic based solid state transformer adds to the complexity of the protection. The FREEDM loop system has a fault current limiter and in addition, the Solid State Transformer (SST) limits the fault current at 2.0 per unit. Former students at ASU have developed the protection scheme using fiber-optic cable. However, during the NSF-FREEDM site visit, the National Science Foundation (NSF) team regarded the system incompatible for the long distances. Hence, a new protection scheme with a wireless scheme is presented in this thesis. The use of wireless communication is extended to protect the large scale meshed distributed generation from any fault. The trip signal generated by the pilot protection system is used to trigger the FID (fault isolation device) which is an electronic circuit breaker operation (switched off/opening the FIDs). The trip signal must be received and accepted by the SST, and it must block the SST operation immediately. A comprehensive protection system for the large scale meshed distribution system has been developed in PSCAD with the ability to quickly detect the faults. The validation of the protection system is performed by building a hardware model using commercial relays at the ASU power laboratory.

  20. Report on task I: fire protection system study

    International Nuclear Information System (INIS)

    This study (1) evaluates, on a comparative basis, the national and international regulatory and insurance standards that serve as guidance for fire protection within the nuclear power industry; (2) analyzes the recommendations contained in the major reports on the Browns Ferry Fire; (3) proposes quantitative safety goals and evaluation methods for Nuclear Power Plant Fire Protection Systems (NPPFPS); (4) identifies potential improvements that may be incorporated into NPPFPS; and (5) recommends a plan of action for continuation of the fire protections systems study

  1. Deployable Aeroshell Flexible Thermal Protection System Testing

    Science.gov (United States)

    Hughes, Stephen J.; Ware, Joanne S.; DelCorso, Joseph A.; Lugo, Rafael A.

    2009-01-01

    Deployable aeroshells offer the promise of achieving larger aeroshell surface areas for entry vehicles than otherwise attainable without deployment. With the larger surface area comes the ability to decelerate high-mass entry vehicles at relatively low ballistic coefficients. However, for an aeroshell to perform even at the low ballistic coefficients attainable with deployable aeroshells, a flexible thermal protection system (TPS) is required that is capable of surviving reasonably high heat flux and durable enough to survive the rigors of construction handling, high density packing, deployment, aerodynamic loading and aerothermal heating. The Program for the Advancement of Inflatable Decelerators for Atmospheric Entry (PAIDAE) is tasked with developing the technologies required to increase the technology readiness level (TRL) of inflatable deployable aeroshells, and one of several of the technologies PAIDAE is developing for use on inflatable aeroshells is flexible TPS. Several flexible TPS layups were designed, based on commercially available materials, and tested in NASA Langley Research Center's 8 Foot High Temperature Tunnel (8ft HTT). The TPS layups were designed for, and tested at three different conditions that are representative of conditions seen in entry simulation analyses of inflatable aeroshell concepts. Two conditions were produced in a single run with a sting-mounted dual wedge test fixture. The dual wedge test fixture had one row of sample mounting locations (forward) at about half the running length of the top surface of the wedge. At about two thirds of the running length of the wedge, a second test surface drafted up at five degrees relative to the first test surface established the remaining running length of the wedge test fixture. A second row of sample mounting locations (aft) was positioned in the middle of the running length of the second test surface. Once the desired flow conditions were established in the test section the dual wedge

  2. Impact of Y2K problem on physical protection system

    International Nuclear Information System (INIS)

    Year 2000 related system failures/problems in Physical Protection System pose no threat to general safety and functioning of any nuclear facility. But there can be potential security threats having radiation safety and non-proliferation concern and hence should be given due importance. Reviewing and testing Physical Protection System for Y2K compliance are easier than other systems as it does not directly affect operation of the plant. The existing emergency response capability at the nuclear facilities should be utilizes effectively to mitigate any Y2K induced events on Physical Protection System with dedicated manpower and channeled efforts

  3. Evolution of Radiation Protection System in Kenya

    International Nuclear Information System (INIS)

    Promulgation of radiation protection legislation in Kenya dates back to 1982, was revised in 1985 and became operational in 1986. This law, the Radiation Protection Act, establishes the Radiation Protection Board as the National Regulatory Authority, with an executive Inspectorate headed by the Secretary to the Board. Subsidiary legislation on radiological practices and standards were subsequently published. The Inspectorate carries out the National programme for notification, authorization, inspection and enforcement. Nuclear applications for peaceful purposes in Kenya are on the increase in all major fields of socio-economic development. Provision of regulatory services, guidance and enforcement procedures, has had a net growth over the last fifteen years. However, staff retention has been declining over the years in a market where job opportunities, with relatively high incentives, are high either inside or outside the country. Human and equipment resource development has therefore not kept pace and this has hampered effective and efficient provision of services. The poor status of the economy has had its impact on delivery of quality, effective and efficient radiation protection services. Provision of radiation services and acquisition of radiation detection and measurement equipment in the country has been generally lacking dating as far back as 1995. During the period 1989 to present, Kenya's Regulatory Authority, the Radiation Protection Board, undertook to provide personal monitoring, quality assurance, radioanalysis, and equipment calibration. Over the years these services have stalled due to outdated equipment most of which have broken down. A maintenance and calibration service for nuclear equipment is an expensive cross-boarder issue. Budgetary constraints, insufficient human and equipment resources, and a perennial 'brain drain' has placed limitations to the effectiveness and efficiency of implementation of the National programmes and slowed the

  4. Evolution of Radiation Protection System in Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Maina, J. A. W.

    2004-07-01

    Promulgation of radiation protection legislation in Kenya dates back to 1982, was revised in 1985 and became operational in 1986. This law, the Radiation Protection Act, establishes the Radiation Protection Board as the National Regulatory Authority, with an executive Inspectorate headed by the Secretary to the Board. Subsidiary legislation on radiological practices and standards were subsequently published. The Inspectorate carries out the National programme for notification, authorization, inspection and enforcement. Nuclear applications for peaceful purposes in Kenya are on the increase in all major fields of socio-economic development. Provision of regulatory services, guidance and enforcement procedures, has had a net growth over the last fifteen years. However, staff retention has been declining over the years in a market where job opportunities, with relatively high incentives, are high either inside or outside the country. Human and equipment resource development has therefore not kept pace and this has hampered effective and efficient provision of services. The poor status of the economy has had its impact on delivery of quality, effective and efficient radiation protection services. Provision of radiation services and acquisition of radiation detection and measurement equipment in the country has been generally lacking dating as far back as 1995. During the period 1989 to present, Kenya's Regulatory Authority, the Radiation Protection Board, undertook to provide personal monitoring, quality assurance, radioanalysis, and equipment calibration. Over the years these services have stalled due to outdated equipment most of which have broken down. A maintenance and calibration service for nuclear equipment is an expensive cross-boarder issue. Budgetary constraints, insufficient human and equipment resources, and a perennial 'brain drain' has placed limitations to the effectiveness and efficiency of implementation of the National programmes and

  5. Design of Wireless Data Acquisition System Based on GPRS for Oil Well Casing pulse Current Cathodic portection%基于GPRS的油井套管脉冲电流阴极保护无线数据采集系统设计

    Institute of Scientific and Technical Information of China (English)

    许庆; 周好斌; 袁森; 张涛

    2015-01-01

    In the exploitation of oilfield, the corrosion of oil well casing is concerned, and the cathodic protection technology is an effective method to inhibit the corrosion of oil well casing. The parameters of the pulse current cathodic protection can be detected, which can reduce the risk of the oil well casing corrosion. Compared with the traditional manual detection, oil well casing in pulsed current cathodic protection of wireless data acquisition system which based on GPRS can realize real time and synchronous monitoring, and improve the detection accuracy and save a lot of human resources, achieve the oil well casing in pulsed current cathodic protection of intensive, digital management.%随着油田的开采,油井套管的腐蚀问题备受关注,脉冲电流阴极保护技术是一种抑制油井套管腐蚀的行之有效的手段。对脉冲电流阴极保护各项参数进行检测,可以降低油井套管发生腐蚀的风险。与传统的人工检测相比,基于GPRS的油井套管脉冲电流阴极保护无线数据采集系统可以对油井套管脉冲电流阴极保护进行实时与同步监测,在提高了检测精度的同时节省了大量的人力资源,实现了油井套管脉冲电流阴极保护的集约化、数字化管理。

  6. Protection system proposed for the FED superconducting coils

    International Nuclear Information System (INIS)

    A failure modes study was the basis for establishing the protection system requirements and for identifying possible design alternatives or options that may be considered. Components of the protection system are discussed with respect to the redundancy and monitoring needed to assure high reliability, as measured by the probability that the system will respond when needed but will not respond inadvertently. High reliability is achieved by making the system fault tolerant using redundancy, decision logic, and computer monitoring

  7. Discussion on several problems in evolution of radiation protection system

    International Nuclear Information System (INIS)

    As viewed from the standpoint of radiation protection practice, it is necessary that the current system of radiological protection should be made more simple and coherent. The human-based protective measures alone are far from having met the requirements of environmental protection in many circumstances. Protecting the environment from ionising radiation would be implicated in radiation protection. Collective dose is an useful indicator, of which applicable extent should be defined. Using such an quantity could help improve radiation protection level, but applicable conditions should be indicated, temporal or spatial. Natural radiation is the largest contributor to the radiation exposure of human. Occupational exposure from natural radiation should be controlled, for occupations such as underground miners and air crew. Controlling both man-made and natural radiation exposure of pregnant women and children needs to be enhanced, especially radiological diagnosis and treatment. China radiation protection community, as a whole, is paying considerable attention to the ICRP's new Recommendations. Prof. Clarke's article 'A Report on Progress towards New Recommendations', a communication from the International Commission on Radiological Protection, has been translated into Chinese and published on Radiation Protection, the Official Journal of China Radiation Protection Society with a view of intensifying awareness of the new Recommendations within more radiation protection workers and people concerned. In addition, a special meeting was convened in early 2002 to address the comments on the new Recommendations. (author)

  8. Broadcast encryption: paving the road to practical content protection systems

    Science.gov (United States)

    Deen, G.; Ponceleon, D.; Leake, Donald, Jr.

    2009-02-01

    Broadcast encryption is a well established alternative to public key encryption for use in content protection systems. It offers significant performance benefits, as well as useful features such a one-to-many delivery, dynamic membership in the authorized receivers group, and provides anonymous access to content, permitting content protection systems to preserve privacy for consumers. Broadcast encryption has been successfully deployed to users for protection of commercial content on digital media such as flash memory devices and optical media for both standard-definition and high-definition content. In this paper, we present the Advanced Secure Content Cluster Technology which applies broadcast encryption to content protection for home media networks

  9. A New Physical Protection System Design and Evaluation Process

    International Nuclear Information System (INIS)

    International Atomic Energy Agency(IAEA) had established security-related department and has been strengthening security measures against possible sabotage. IAEA enforces the recommendations for the physical protection of NPPs in the INFCIRC/ 225/Rev.5 to the member states and U.S. NRC also enforces the similar requirements in 10 CFR 73.55. Thus, in order to let Korean NPPs meet the new requirements in INFCIRC/225/Rev.5 or U.S. NRC requirements, Korea nuclear licensee should develop or establish appropriate physical protection system (PPS) design methods for the physical protection of the operating NPPs and new NPPs. KHNP is doing the project of 'Development of APR1400 Physical Protection System Design (2012- 2015, KHNP/KAERI /KEPCO E-C)'. This paper describes overview of a physical protection system (PPS) design and evaluation for an advanced nuclear power plant. It found that a new physical protection system (PPS)design and evaluation. KHNP is doing the project of Physical Protection System design according to U.S. NRC requirements and IAEA requirements in INFCIRC /225 /Rev.5 and will complete by 7.31, 2015 for development of APR1400 Physical Protection System. After completing this project, the results of project are expected to apply new NPPs

  10. Large-Area Crystalline Silicon Solar Cell Using Novel Antireflective Nanoabsorber Texturing Surface by Multihollow Cathode Plasma System and Spin-On Doping

    OpenAIRE

    Utpal Gangopadhyay; Sukhendu Jana; Sayan Das

    2013-01-01

    We present 11.7% efficient p-type crystalline silicon solar cells with a nanoscale textured surface and no dielectric antireflection coating. We propose nanocrystalline-like textured surface consisting of nanocrystalline columnar structures of diameters from 50 to 100 nm and depth of about 500 nm formed by reactive-ion etching (RIE) in multihollow cathode system. This novel nano textured surface acts as an antireflective absorbing surface of c-Si abbreviate as ARNAB (antireflective nanoabsorb...

  11. Practical Approach on Lightning and Grounding Protection System

    OpenAIRE

    Shan Jose Varghese

    2015-01-01

    Lightning Protection and Grounding of Electrical and Mechanical equipment’s for the Protection of the Human Beings, Structure of the building and equipment protection, safe working of the Worker at Industry as per my latest practical knowledge in the site environment in extreme climatic condition of low lying areas of the Gulf Region in the challenging projects. All the conductor calculation, Lightning Risk Factor calculations, all the system information regarding the ...

  12. Method and System for Protection of Automated Control Systems for “Smart Buildings”

    Directory of Open Access Journals (Sweden)

    Dmitry Mikhaylov

    2013-07-01

    Full Text Available The paper is related to system and method for protection of an automated control system (ACS against un-authorized devices connected to the ACS via wired or wireless channels that substantially obviates the disadvantages of the related art. The protection system monitors the signals spreading in the network analyzing the performance of the network for malicious code or hidden connections of attacker. The system is developed specifically for this purpose and it can protect the industrial control systems more effectively than standard anti-virus programs. Specific anti-virus software installed on a central server of the automated control system protects it from software-based attacks both from internal and external offenders. The system comprises a plurality of bus protection devices of different types, including any of a twisted-pair protection device, a power lines protection device, On-Board Diagnostics signal protocol protection device, and a wireless protection device.

  13. Annexes to the lecture on reactor protection system including engineered features actuation system

    International Nuclear Information System (INIS)

    The present paper deals with the fundamentals for a reactor protection system and discusses the following topics: - System lay-out - Analog measured data acquisition - Analog measured data processing - Limit value generation and logical gating - Procesing of the reactor protection actuation signals - Decoupling of the reactor protection system - Mechanical lay-out - Monitoring system and - Emergency control station. (orig./RW)

  14. Criminal law repercussions on the Civil Protection System

    Science.gov (United States)

    Altamura, M.; Musso, L.

    2009-09-01

    The legal systems of our Countries provide the citizenship with a high level of protection. Personal safety and the protection of property are guaranteed by the State through organized structures among which we can include the Civil Protection. The progress of science and technology has greatly improved monitoring tools, currently used by the Civil Protection, which allow, to a certain extent, to predict and prevent risk and natural hazards. The assertion of an individual right, which in some cases has reached a constitutional rank, to benefit from Civil Protection services and the widespread perception throughout the citizenship of the competence of the system to prevent disasters, often causes people to take legal action against Civil Protection authorities should they fail in their duties to protect. However, the attempt of having both recognized an economic compensation for the suffered loss and the punishment of those whom misled, frequently undergoes criminal law. This process could have results that may jeopardize the effectiveness of Civil Protection service without meeting citizens’ demands. A dual effort is thus necessary in order to solve such a problem. On the one hand, an interdisciplinary knowledge needs to pervade criminal law in an attempt to relieve its self-referentiality and pretended supremacy. On the other hand an alternative, and more agile, system -such as civil or administrative law- has to be identified in order to respond to the legitimate requests for protection in the case of a faulty behaviour of the authorities.

  15. NSTX-U Digital Coil Protection System Software Detailed Design

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-06-01

    The National Spherical Torus Experiment (NSTX) currently uses a collection of analog signal processing solutions for coil protection. Part of the NSTX Upgrade (NSTX-U) entails replacing these analog systems with a software solution running on a conventional computing platform. The new Digital Coil Protection System (DCPS) will replace the old systems entirely, while also providing an extensible framework that allows adding new functionality as desired.

  16. Design principles for radiological protection instrumentation systems

    International Nuclear Information System (INIS)

    This Code of Practice takes the form of recommendations intended for designers and installers of Radiological Protection Instrumentation, and should also be of value to the newcomer to the R.P.I. field. Topics are discussed under the following headings: outline of R.P.I. requirements, specifying the requirement, satisfying the requirements, (overall design, availability and reliability, information display, human factors, power supplies, manufacture, quality assurance, testing, and cost analysis), supply, location and operation of the equipment, importance of documentation. (U.K.)

  17. Radiation protection of vitamins in aqueous systems

    International Nuclear Information System (INIS)

    A study of the radiation induced decomposition of the B-group vitamins has been carried out in aqueous media at room temperature as well as in rigid matrices at low temperature. The detailed results on the effect of glucose and oxygen as protective additives at the different temperatures are presented in the case of Thiamine (Vitamin B1). Comparative data are given on the extent of decomposition of this and other vitamins of the B-group at room temperature and at 193 K. The importance of these results in connection with the radiation sterilization of pharmaceutical preparations is indicated. (author)

  18. Strengthening Child Protection Systems for Unaccompanied Migrant Children in Mozambique

    DEFF Research Database (Denmark)

    Verdasco Martinez, Andrea

    This research sets out to understand the why, how and with whom of rural-urban internal migration of children to Ressano Garcia, a border town between Mozambique and South Africa. It addresses the overarching research question of how to strengthen child protection systems for unaccompanied migrant...... that child protection systems must respond to the unique situation of migrant children’s needs. Child protection and migration policies need to strike a balance between discouraging unsafe migration, which has the potential to expose children to violence, and ensuring that systems are in place for safe...

  19. The justification for developing a system of environmental radiation protection

    International Nuclear Information System (INIS)

    This paper presents concluding points relevant to the question whether (and why) it is justified to spend resources for the development of a system of environmental radiation protection. The paper puts the issue in historical perspective to radiation protection philosophy and to current trends in ecology and 'green' politics. It also looks at the issue of scientific rationality, paradigms and beliefs. Among the arguments for the development of a System the paper considers public concerns, integration in overall environmental policy, uncertainties and sustainable development. The paper also examines the prospects for the development of a System within the EU and offers some general considerations on the scope of environmental protection. (author)

  20. Discussion on radiation protection system from ethical issues

    International Nuclear Information System (INIS)

    This paper discussed the relationship between radiation protection system and ethical principle, viz. equity and efficiency. According to the authors' opinions, the main problem that the system of radiation protection facing now is the dose-limitation principle cannot incarnate the equity principle completely. Even though the distinguishing between practice and intervention is no other than solving the problem, but the scheme is not perfect still. Ethical issues should be given more attention and be more researched when we try to modify the radiation protection system today

  1. Mechanisms of protection of information in computer networks and systems

    OpenAIRE

    Sergey Petrovich Evseev; Oleksandr Vasilievich Dorokhov; Olga Grigorievna Korol

    2011-01-01

    Protocols of information protection in computer networks and systems are investigated. The basic types of threats of infringement of the protection arising from the use of computer networks are classified. The basic mechanisms, services and variants of realization of cryptosystems for maintaining authentication, integrity and confidentiality of transmitted information are examined. Their advantages and drawbacks are described. Perspective directions of development of cryptographic transformat...

  2. The Dutch system of legal protection in public procurement procedures

    NARCIS (Netherlands)

    van Heeswijck, Arthur

    2015-01-01

    The legal protection of entrepreneurs in public procurement procedures has been a point of concern to the European Union legislator, leading to the adoption of well-known the Remedies Directives. This article examines the conformity of the Dutch system of judicial protection in the procurement field

  3. Selectivity of power system protections at power swings in power system

    Directory of Open Access Journals (Sweden)

    Jan Machowski

    2012-12-01

    Full Text Available The paper discusses out-of-step protection systems such as: generator pole slip protections, out of step tripping protections, distance protections of step-up transformer, distance protections of transmission lines and transformers, power swing blocking, and special out-of-step protection. It is shown that all these protections make up a protection system, to which a setting concept uniform for the entire power system has to be applied. If a power system is inappropriately equipped with these protections, or their settings are inappropriate, they may operate unselectively, thus contributing to the development of power system blackouts. In the paper the concepts for a real power system are given for the two stages: target stage fully compliant with selectivity criteria, and transitional stage between the current and target stages.

  4. Enhanced photoelectrochemical cathodic protection performance of the C{sub 3}N{sub 4}@In{sub 2}O{sub 3} nanocomposite with quasi-shell–core structure under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Mengmeng; Chen, Zhuoyuan, E-mail: zychen@qdio.ac.cn; Bu, Yuyu

    2015-01-05

    Highlights: • The C{sub 3}N{sub 4}@In{sub 2}O{sub 3} composite with quasi-shell–core structure is prepared. • Photoelectrochemical cathodic protection performance of this composite was studied. • C{sub 3}N{sub 4} coating on In{sub 2}O{sub 3} dramatically enhances its light absorption capability. • C{sub 3}N{sub 4} coating on In{sub 2}O{sub 3} dramatically enhances its photoelectrochemical properties. • C{sub 3}N{sub 4} coating on In{sub 2}O{sub 3} dramatically enhances its electron transfer capability. - Abstract: Carbon nitride@Indium oxide (C{sub 3}N{sub 4}@In{sub 2}O{sub 3}) composite with quasi-shell–core structure was successfully prepared in this work. The photoinduced open circuit potential and current density results show that the C{sub 3}N{sub 4}@In{sub 2}O{sub 3} composite with quasi-shell–core structure could provide the optimal photoelectrochemical cathodic protection capability for 304 stainless steel under visible light when the adding amount of C{sub 3}N{sub 4} in the C{sub 3}N{sub 4}@In{sub 2}O{sub 3} composite is 3 wt%. The light absorption capability of the C{sub 3}N{sub 4}@In{sub 2}O{sub 3} composite was enhanced due to the synergistic effect of heterojunction structure. According to the HRTEM images, photoinduced Volt–Ampere characteristic curves and electrochemical impedance spectra, the ultrathin coating layer of C{sub 3}N{sub 4} on the surface of In{sub 2}O{sub 3} helps to form a heterojunction electric field at the interface between C{sub 3}N{sub 4} and In{sub 2}O{sub 3}, which enhances the separation efficiency of the photogenerated electron–hole pairs. Excessive C{sub 3}N{sub 4} will decline the photoelectrochemical cathodic protection of this composite due to the lower intrinsic electronic mobility and the lower photoelectric conversion property of C{sub 3}N{sub 4}.

  5. Experiences of corrosion and corrosion protection in seawater systems in the Nordic countries

    International Nuclear Information System (INIS)

    A summary is given of the experience of the corrosion resistance of pumps, heat exchangers, valves and pipings in different seawater cooling systems in Scandinavia, including power reactor cooling systems in Finland and Sweden. For pumps and heat exchangers the experience has been so extensive that a clear picture of today's standing can be given. Owing to scanty data concerning valves and pipes, the survey of the corrosion in these components is less well supported. Vertically extended centrifugal pumps are the pumps in general use in power plant cooling systems. To counteract corrosion on pump riser and pump casing having an organic surface coating, and on stainless steel shafts and impellers, these components should be provided with internal and external cathodic protection. For tube and plate type heat exchangers, titanium has proved to be the best material choice. Rubber-enclosed carbon steel pipings, or pipings having a thick coating of epoxy plastic, have shown very strong corrosion resistance in power plant seawater cooling systems. Valves in seawater systems have primarily been affected by corrosion due to poorly executed or damaged organic coating on cast iron. Different seawater-resistant bronzes (red bronze, tin bronze and aluminium bronze) are therefore preferable as valve materials

  6. Cobalt, titanium or cerium oxide protective coatings for the nickel cathode of the molten carbonate fuel cells; Revetements protecteurs a base d'oxyde de cobalt, de titane ou de cerium pour la cathode de nickel des piles a combustible a carbonates fondus

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza Blanco, L.

    2003-10-15

    The aim of this work is to combine the MCFC cathode Li{sub x}Ni{sub 1-x}O properties to those of the protective coatings of LiCoO{sub 2}, Li{sub 2}TiO{sub 3} or of CeO{sub 2}, less soluble in the molten carbonates. In the cases of LiCoO{sub 2}, have been carried out by controlled potential coulometry in aqueous solution, a deposition of Co{sub 3}O{sub 4} on dense Ni. The cobalt oxide reacts rapidly in the Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3} medium at 650 C to give LiCoO{sub 2}, a spinel cubic phase revealed by Raman spectroscopy. (O.M.)

  7. Understanding of radiation protection in medicine. Pt. 2. Occupational exposure and system of radiation protection

    International Nuclear Information System (INIS)

    Using a questionnaire we investigated whether radiation protection is correctly understood by medical doctors (n=140) and nurses (n=496). Although medical exposure is usually understood by medical doctors and dentists, their knowledge was found to be insufficient. Sixty-eight percent of medical doctors and 50% of dentists did not know about the system of radiation protection. Dose monitoring was not correctly carried out by approximately 20% of medical staff members, and medical personnel generally complained of anxiety about occupational exposure rather than medical exposure. They did not receive sufficient education on radiation exposure and protection in school. In conclusion, the results of this questionnaire suggested that they do not have adequate knowledge about radiation exposure and protection. The lack of knowledge about protection results in anxiety about exposure. To protect oneself from occupational exposure, individual radiation doses must be monitored, and medical practice should be reconsidered based on the results of monitoring. To eliminate unnecessary medical and occupational exposure and to justify practices such as radiological examinations, radiation protection should be well understood and appropriately carried out by medical doctors and dentists. Therefore, the education of medical students on the subject of radiation protection is required as is postgraduate education for medical doctors, dentists and nurses. (author)

  8. LE SYSTEME DE PROTECTION SOCIALE EN ALGERIE

    OpenAIRE

    Perret, Cécile

    2012-01-01

    L'objectif de cette recherche est de dresser un état des lieux de la protection social en Algérie. La première partie présente le cadre conceptuel de la solidarité intergénérationnelle et les spécificités caractéristiques des pays " du Sud ". La seconde partie s'attache à présenter les nouvelles dynamiques de la solidarité intergénérationnelle en Algérie à travers une présentation des grandes mutations de la société algérienne et de son " informalisation ". Enfin, la troisième partie présente...

  9. MediaEval 2015 Drone Protect Task: Privacy Protection in Surveillance Systems Using False Coloring

    OpenAIRE

    Çiftçi, Serdar; Korshunov, Pavel; Akyüz, Ahmet Oguz; Ebrahimi, Touradj

    2015-01-01

    In this paper, we share our results for privacy protection using false coloring in surveillance systems in the Drone Protect Task. The aim is obscuring sensitive regions that are privacy related without sacrificing intelligibility and pleasantness. The idea in false coloring is transforming the colors of an image using a color palette into a different set of colors in which private information is harder to recognize. The method can be applied globally to the whole frame or to a given region o...

  10. Some modifications in the protection system of a BWR caused by fire protection requirements

    International Nuclear Information System (INIS)

    A group of experts have been nominated by licensing authorities to work out fire protection recommendations for the first Austrian nuclear power plant. These requirements necessitated a number of modifications in design and lay-out of the reactor safety systems. In addition to the usual physical separation of redundant cable race-ways, it was necessary to modify electric circuits in those areas where redundances could not be fully separated by fire boundaries. Examples of such changes in the logic circuits of the reactor protection system and the instrumentation of the reactor shut-down system are described. (author)

  11. In Situ Diagnostic Sensors for Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Low-profile, embedded sensors are proposed for condition monitoring and health management (HM) of thermal protection systems. The sensors will be fabricated using a...

  12. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation combines a new generation low power ice protection system with a novel path to certification that is based upon requirements that turbine engines be...

  13. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal presents a dual approach to the development and certification of an alternative system for ice protection of turbine engine inlets. It combines a new...

  14. Thermal Protection System Materials (TPSM): 3D MAT Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The 3D MAT Project seeks to design and develop a game changing Woven Thermal Protection System (TPS) technology tailored to meet the needs of the Orion...

  15. Evaluation and diagnosis of the cathodic protection of ducts in the left margin of the Tonala River of the Superintendencia General de Ductos Minatitlan; Evaluacion y diagnostico de la proteccion catodica en la margen izquierda del Rio Tonala de la Superintendencia General de Ductos Minatitlan

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez N, Miguel A; Malo T, Jose M; Munoz Ledo C, Ramon; Uruchurtu C, Jorge; Castrejon G, Rafael [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Sanchez G, Luis; Algarra M, Raul; Abreu L, Emilio [Gerencia de Mantenimiento, Pemex (Mexico)

    2003-07-01

    The present study contains the measurements obtained as a part of the evaluation of the protection system of ducts located in the left margin of the Tonal River, made by the Gerencia de Materiales y Procesos Quimicos of the Instituto de Investigaciones Electricas (IIE) during the last trimester of year 2001. Also, the measurements of potential in conditions of instantaneous ignition and extinguished in measuring posts of the duct in Rights of Way (DDV) Tonala-Nudo Teapa 23 are studied, in order to determine the real protection level reached by the cathodic protection system, the possible unprotected zones and the possible corrective measures that lead to a safe operation of the ducts. [Spanish] El presente estudio contiene las mediciones obtenidas como parte de la evaluacion del sistema de proteccion de los ductos ubicados en la margen izquierda del rio Tonala, realizadas por la Gerencia de Materiales y Procesos Quimicos del Instituto de Investigaciones Electricas (IIE) durante el ultimo trimestre del ano 2001. Asimismo, se tratan las mediciones de potencial en condiciones de encendido y apagado instantaneo en postes de medicion del ducto en los Derechos De Via (DDV) Tonala-Nudo Teapa 23, con el proposito de determinar el nivel real de proteccion alcanzado por el sistema de proteccion catodica, las posibles zonas desprotegidas y las posibles medidas correctivas que conduzcan a una operacion segura de los ductos.

  16. System Protection Schemes in Eastern Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Joana

    units. It was observed that the addition of large amounts of wind power to a relatively weak power system without reinforcements may cause voltage instability in the power system. The maximum power transfer in the heavily loaded system with two large off-shore wind farms is approached at about 70% of...... measurement of active power in the tie-lines. The power transfer in the 132-kV system is improved by additional reactive power support in the system using voltage control devices and/or SPS control actions: adjustment of adequate SVC setpoint, switching of additional capacitive shunts, start-up of Masnedø gas...... of wind turbines based on induction generators. On the other hand, the wind turbine rejection is associated with loss of active power that has to be compensated using immediate reserves. To avoid unnecessary disconnection of wind turbines, fast fault clearance time is the main factor. Phasor...

  17. Analysis of cathode geometry to minimize cathode erosion in direct current microplasma jet

    Energy Technology Data Exchange (ETDEWEB)

    Causa, Federica [Dipartimento di Scienze dell' Ambiente, della Sicurezza, del Territorio, degli Alimenti e della Salute, Universita degli studi di Messina, 98122 Messina (Italy); Ghezzi, Francesco; Caniello, Roberto; Grosso, Giovanni [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, EURATOM-ENEA-CNR Association, Via R. Cozzi 53, 20125 Milano (Italy); Dellasega, David [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, EURATOM-ENEA-CNR Association, Via R. Cozzi 53, 20125 Milano (Italy); Dipartimento di Energia, Politecnico di Milano, Via Ponzio 34/3, 20133 Milano (Italy)

    2012-12-15

    Microplasma jets are now widely used for deposition, etching, and materials processing. The present study focuses on the investigation of the influence of cathode geometry on deposition quality, for microplasma jet deposition systems in low vacuum. The interest here is understanding the influence of hydrogen on sputtering and/or evaporation of the electrodes. Samples obtained with two cathode geometries with tapered and rectangular cross-sections have been investigated experimentally by scanning electron microscopy and energy dispersion X-ray spectroscopy. Samples obtained with a tapered-geometry cathode present heavy contamination, demonstrating cathode erosion, while samples obtained with a rectangular-cross-section cathode are free from contamination. These experimental characteristics were explained by modelling results showing a larger radial component of the electric field at the cathode inner wall of the tapered cathode. As a result, ion acceleration is larger, explaining the observed cathode erosion in this case. Results from the present investigation also show that the ratio of radial to axial field components is larger for the rectangular geometry case, thus, qualitatively explaining the presence of micro-hollow cathode discharge over a wide range of currents observed in this case. In the light of the above findings, the rectangular cathode geometry is considered to be more effective to achieve cleaner deposition.

  18. Sb implantation for bipolar buried layers using SbF5 in a cold-cathode implantation system

    International Nuclear Information System (INIS)

    Antimony pentafluoride (SbF5) has been successfully used as a source for antimony implantation into silicon substrates. Modifications of a cold-cathode implantation system to accommodate the use of SbF5 are discussed. The dominant antimony current peaks of the ion beam current spectrum were implanted, and identified by Auger analysis. Using a graphical analysis method, other ionic species of the beam spectrum were identified. It was determined that both singly and doubly ionized Sb in isotype forms of mass 121 and 123 amu are formed in concentrations which correlate to the naturally found concentrations of approximately 57% and 43%. Other ionic species were identified as 19F+, 121SbF2+, 123SbF2+, 121SbF2+, 123SbF+, 121SbF+2, and 123SbF2+. Beam current levels of singly ionized 121Sb were found to be approximately 30 μA with no attempt made to maximize the beam current available. SUPREM II simulations were performed to determine approximate dose and energy levels consistent with buried layer profile parameters. Based on these simulations, the 30 μA beam current was found to result in acceptable implantation times of approximately 15 min for dose levels of 3 x 1015 cm-2. Both and silicon wafers were implanted and the annealing and defect nature studied. It was found that the defect nature of and silicon differ significantly in that a residual subsurface dislocation network was observed on silicon wafers. (orig.)

  19. Reactor core protection system using a 4-channel microcomputer

    International Nuclear Information System (INIS)

    A four channel microcomputer system was fitted in Grafenrheinfeld NPP for local core protection. This system performs continuous on-line monitoring of peak power density, departure from nucleate boiling ratio and fuel duty. The system implements limitation functions with more sophisticated criteria and improved accuracy. The Grafenrheinfeld system points the way to the employment of computer based limitation system, particularly in the field of programming language, demarkation of tasks, commissioning and documentation aids, streamlining of qualification and structuring of the system. (orig.)

  20. Multibiometrics system : templates, template protection and remote authentication

    OpenAIRE

    Shrestha, Ashish

    2014-01-01

    The intention behind writing this thesis was to provide a brief description on biometric security systems, multi-biometrics, implementation of multi-biometrics in remote authentication systems, and template protection. The thesis also discusses few of the available protocols proposed by researchers for template protection and remote authentication. The information for this thesis has been acquired through various articles, journals, books, internet resources, documentary films, magazines and ...

  1. Multi Agent System Based Wide Area Protection against Cascading Events

    DEFF Research Database (Denmark)

    Liu, Zhou; Chen, Zhe; Liu, Leo;

    2012-01-01

    In this paper, a multi-agent system based wide area protection scheme is proposed in order to prevent long term voltage instability induced cascading events. The distributed relays and controllers work as a device agent which not only executes the normal function automatically but also can be mod...... effectiveness of proposed protection strategy. The simulation results indicate that the proposed multi agent control system can effectively coordinate the distributed relays and controllers to prevent the long term voltage instability induced cascading events....

  2. EMPLOYING PEOPLE WITH DISABILITIES: THE ROMANIAN PROTECTED UNITS SYSTEM

    OpenAIRE

    2013-01-01

    The protected units are an answer to the employment increase goal for people with disabilities in Romania. With a history of two decades, the protected units system became visible in the context of the social economy. The present paper is based on qualitative research and focuses on how the social actors in this employment opportunity address its benefits. There are small companies, NGOs, people with disabilities and representative authorities named here. Even though the system does not alway...

  3. Survivability analysis for continuous data protection system based on SMP

    Science.gov (United States)

    Xiong, Qi; Liu, Hui; Liu, Lin; Wu, Shizhong

    2011-10-01

    As a Novel Disaster surviving technology, Continuous Data Protection(CDP) can restore the protected system to the state of any time point in the past. Until now, no efficient survivability evaluation method for CDP system is developed. Regarding this problem, a semi-markov process(SMP) is applied to survivability of CDP, SMP model for CDP survivability analysis is established, quantitative survivability metric is calculated and some survivability enhancing strategies are proposed accordingly.

  4. The Philosophy of the New Radiation Protection System

    International Nuclear Information System (INIS)

    The International Commission on Radiological Protection has proposed a new philosophy of radiation protection. An important component in the proposed system of protection is the principle If the individual is sufficiently protected from a source, then society is also protected from that source. This principle is here analysed and found to be subject to several problems. The principle reflects the controversial ethical position that the likely harm to several people can be ignored as long as the individual risk is small. The ICRP states that the new system involves a change from a previous utilitarian ethics to an individual-oriented philosophy. It is argued that a rights-based or a duty-based ethic requires a more risk avert interpretation of when an individual is sufficiently protected than what the proposal suggests. It is concluded that the proposed principle contradicts the other important principle in the new system - the optimisation principle. Due to these problems it is suggested that the ICRP ought to discard the proposed principle from the new system of radiation protection. (Author) 7 refs

  5. The Philosophy of the New Radiation Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, P.

    2004-07-01

    The International Commission on Radiological Protection has proposed a new philosophy of radiation protection. An important component in the proposed system of protection is the principle ''If the individual is sufficiently protected from a source, then society is also protected from that source''. This principle is here analysed and found to be subject to several problems. The principle reflects the controversial ethical position that the likely harm to several people can be ignored as long as the individual risk is small. The ICRP states that the new system involves a change from a previous utilitarian ethics to an individual-oriented philosophy. It is argued that a rights-based or a duty-based ethic requires a more risk avert interpretation of when an individual is sufficiently protected than what the proposal suggests. It is concluded that the proposed principle contradicts the other important principle in the new system - the optimisation principle. Due to these problems it is suggested that the ICRP ought to discard the proposed principle from the new system of radiation protection. (Author) 7 refs.

  6. Penetration testing protecting networks and systems

    CERN Document Server

    Henry, Kevin M

    2012-01-01

    This book is a preparation guide for the CPTE examination, yet is also a general reference for experienced penetration testers, ethical hackers, auditors, security personnel and anyone else involved in the security of an organization's computer systems.

  7. PAYROLL SYSTEM AND SOCIAL PROTECTION IN GERMANY

    Directory of Open Access Journals (Sweden)

    NĂSTASIE MIHAELA – ANDREEA

    2015-03-01

    Full Text Available Any payment system must establish a connection between the entity and the revenue performance of employees between the financial balance of the entity and needs to satisfy some needs of the individuals. A goal is not always easy to follow is to establish fairness in the workplace in relation to the report results. Even if the system is a fair wage, it is necessary that employees perceive and understand this. German economic success was achieved thanks to a competent management and an effort from employees, which is characterized by more order, competent and highly skilled, resulting in a competition between the management and the german economy. German management uses the tools of the pay system and the welfare system.

  8. Computer-aided protective system (CAPS)

    International Nuclear Information System (INIS)

    A method of improving the security of materials in transit is described. The system provides a continuously monitored position location system for the transport vehicle, an internal computer-based geographic delimiter that makes continuous comparisons of actual positions with the preplanned routing and schedule, and a tamper detection/reaction system. The position comparison is utilized to institute preprogrammed reactive measures if the carrier is taken off course or schedule, penetrated, or otherwise interfered with. The geographic locater could be an independent internal platform or an external signal-dependent system utilizing GPS, Loran or similar source of geographic information; a small (micro) computer could provide adequate memory and computational capacity; the insurance of integrity of the system indicates the need for a tamper-proof container and built-in intrusion sensors. A variant of the system could provide real-time transmission of the vehicle position and condition to a central control point for; such transmission could be encrypted to preclude spoofing

  9. High hydrogen loading of thin palladium wires through alkaline earth carbonates' precipitation on the cathodic surface - evidence of a new phase in the Pd-H system

    International Nuclear Information System (INIS)

    A new protocol for the electrolytic loading of hydrogen (H) in thin palladium (Pd) wires has been developed. In order to increase the cathodic overvoltage, which is known to be the main parameter capable to enhance the electrolytic H loading of Pd, the catalytic action of the Pd surface versus H-H recombination has been strongly reduced by precipitation of a thin layer of alkaline-earth carbonates on the cathode. A set of electrolytes has been employed, containing small amounts of hydrochloric or sulfuric acid and strontium or calcium ions. The H loading has been continuously evaluated through ac measurements of the Pd wire resistance. Uncommonly low resistivity values, leading to an estimate of exceptionally high H loading, have been observed. Evidence of the existence of a new phase in the very high H content region of the Pd-H system has been inferred on the basis of the determination of the temperature coefficient of the electrical resistivity. Mainly for this purpose a thin layer of Hg was galvanically deposed on the cathodic surface, in order to prevent any H deloading during the measurements. The results have been fully reproduced in other 2 well equipped and experienced Laboratories (Italy, USA)

  10. Development and testing of a hybrid system with a sub-kW open-cathode type PEM (proton exchange membrane) fuel cell stack

    International Nuclear Information System (INIS)

    In this study, the performance of a polymer electrolyte membrane fuel cell stack has been evaluated for a hybrid power system test platform. To simulate vehicle acceleration, the stack was operated under dynamic-loading, and to demonstrate the exchange of power flow between two power sources the hybrid power system was tested under three different modes. A unit cell was fabricated for high stack performance and the stack was constructed with 18 open-cathode type fuel cells. Air which acts as a coolant as well as an oxidant for electrochemical reactions is provided by a pair of fans. The capabilities of the stack for hybrid power system test platform were validated by successful dynamic-loading tests. The performance of the stack for various air fan voltage was evaluated and an optimal value was concluded. The conditions like inlet temperature of H2 and the stack current were established for maximum power. It was also found that humidification of hydrogen at anode inlet degrades the stack performance and stability due to flooding. Evidence shows that for the higher overall performance, the fuel cell acts continuously on constant current output. The study contributes to the design of mobility hybrid system to get better performance and reliability. - Highlights: • An open-cathode type PEMFC (polymer electrolyte membrane fuel cell) stack (rated output 300 W) was fabricated. • The open-cathode configuration simplifies the design of a stack system. • Assess the feasibility of combining a fuel cell stack in a hybrid system. • The study contributes to the design of mobility hybrid system to get better performance and reliability

  11. Active wireless temperature sensors for aerospace thermal protection systems

    Science.gov (United States)

    Milos, Frank S.; Karunaratne, K. S. G.

    2003-07-01

    Vehicle system health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles in order to reduce life-cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to advance inspection and health management technologies for thermal protection systems. This paper summarizes a joint effort by NASA Ames and Korteks to develop active "wireless" sensors that can be embedded in the thermal protection system to monitor subsurface temperature histories. These devices are thermocouples integrated with radio-frequency identification circuits to enable non-contact communication of temperature data through aerospace thermal protection materials. Two generations of prototype sensors are discussed. The advanced prototype collects data from three type-k thermocouples attached to a 25-mm square integrated circuit and can communicate through 7 to 10 cm thickness of thermal protection materials.

  12. Implementation of FPGA-Based Diverse Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Soo Yun; Lee, Yoon Hee; Shon, Se Do; Baek, Seung Min [KEPCO Engineering and Construction Company Inc., Daejeon (Korea, Republic of)

    2015-10-15

    Obsolete analog and digital hardware platforms in NPPs are commonly replaced with programmable logic controller (PLC) and distributed control system (DCS). Field programmable gate arrays (FPGAs) are highlighted as an alternative to obsolete hardware platforms. FPGAs are digital integrated circuits (ICs) that contain the configurable (programmable) blocks of logic along with configurable interconnections among these blocks. Designers can configure (program) such devices to perform a tremendous variety of tasks. FPGAs have been evolved from the technology of programmable logic device (PLD). Nowadays, they can contain millions of logic gates by nanotechnology and can be used to implement extremely large and complex functions that previously could be realized only using application specific integrated circuits (ASICs). This paper presents the implementation of an FPGA-based diverse protection system (DPS) which executes the protective functions in NPP when the protective functions of the plant protection system (PPS) fails.

  13. A collision avoidance system for workpiece protection

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, D.J.; Weber, T.M.; Novak, J.L. [Sandia National Labs., Albuquerque, NM (United States); Maslakowski, J.E. [Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.

    1995-04-01

    This paper describes an application of Sandia`s non-contact capacitive sensing technology for collision avoidance during the manufacturing of rocket engine thrust chambers. The collision avoidance system consists of an octagon shaped collar with a capacitive proximity sensor mounted on each face. The sensors produced electric fields which extend several inches from the face of the collar and detect potential collisions between the robot and the workpiece. A signal conditioning system processes the sensor output and provides varying voltage signals to the robot controller for stopping the robot.

  14. The Adaptive Greenhouse an Integrated Systems Approach to Developing Protected Cultivation Systems

    OpenAIRE

    Henten, van, J.W.; Bakker, J.C.; Marcelis, L.F.M.; Ooster, van 't, A.; Dekker, E.; Stanghellini, C.; Vanthoor, B.H.E.; Randeraat, van, B.; Westra, J

    2006-01-01

    Protected cultivation systems are used throughout the world as a powerful instrument to produce crops. They protect the crops from unfavorable outdoor climate conditions and pests and offer the opportunity to modify the indoor climate to create an environment that is optimal for crop growth and production, both in terms of quality and quantity. A quick scan of protected cultivation systems presently in use reveals that various types of protected cultivation systems have evolved in time. These...

  15. Evolution of the Radiological Protection System and its Implementation.

    Science.gov (United States)

    Lazo, Edward

    2016-02-01

    The International System of Radiological Protection, developed, maintained, and elaborated by the International Commission on Radiological Protection (ICRP) has, for the past 50 y, provided a robust framework for developing radiological protection policy, regulation, and application. It has, however, been evolving as a result of experience with its implementation, modernization of social awareness of a shrinking world where the Internet links everyone instantly, and increasing public interest in safety-related decisions. These currents have gently pushed the ICRP in recent years to focus more sharply on particular aspects of its system: optimization, prevailing circumstances, the use of effective dose and aspects of an individual's risk, and consideration of the independent implementation of the international system's elements. This paper will present these issues and their relevance to the ICRP system of protection and its evolution. The broader framework of radiological protection (e.g., science, philosophy, policy, regulation, implementation), of which the ICRP is an important element, will provide a global, equally evolving context for this characterization of the changing ICRP system of radiological protection. PMID:26717167

  16. A new dispenser cathode with dual-layer

    Science.gov (United States)

    Li, Yutao; Zhang, Honglai; Liu, Pukun; Zhang, Mingchen

    2005-09-01

    The emission and surface characteristics of the dispenser cathode coated with Os-W alloy and that coated with Os-W/Re are studied and compared. The dispenser cathode coated with Os-W/Re has been applied in electron gun measurement system for making measurement of higher emission current and life test. We called the cathode coated with Os-W/Re as the cathode with dual-layer. It is found that the dispenser cathode coated with dual-layer has higher current density than that coated only with Os-W alloy. After being activated, the cathode coated with dual-layer presents ternary composition on the surface of it. The W surface composition does not rise with time comparing with that of the cathode coated with Os-W alloy. In electron gun, the dispenser cathode coated with dual-layer has pulse current density of 30 A/cm 2 and life of more than 800 h.

  17. A new dispenser cathode with dual-layer

    International Nuclear Information System (INIS)

    The emission and surface characteristics of the dispenser cathode coated with Os-W alloy and that coated with Os-W/Re are studied and compared. The dispenser cathode coated with Os-W/Re has been applied in electron gun measurement system for making measurement of higher emission current and life test. We called the cathode coated with Os-W/Re as the cathode with dual-layer. It is found that the dispenser cathode coated with dual-layer has higher current density than that coated only with Os-W alloy. After being activated, the cathode coated with dual-layer presents ternary composition on the surface of it. The W surface composition does not rise with time comparing with that of the cathode coated with Os-W alloy. In electron gun, the dispenser cathode coated with dual-layer has pulse current density of 30 A/cm2 and life of more than 800 h

  18. A critical review of the system of radiation protection

    International Nuclear Information System (INIS)

    Our modern, information society is increasingly interested in transparency and participation in many aspects of government, and this is particularly true in areas involving public health and environmental protection. Radiation protection is no exception to this trend. Scientific rationale that was once sufficient to explain radiation protection theory and practice is no longer adequate. The need to address and communicate theory, practice and the decision-making process to a wider audience has given rise to numerous debates and led the radiation protection community to revisit the framework of the system of radiation protection. The very fundamentals of the system of radiation protection continue to be questioned in a healthy fashion, and many aspects have been identified which could better serve stakeholders given some additional thought in the light of modern societal needs. This report is the summary of the NEA's first reflections in this area, and describes those aspects of the current international system of radiation protection that could be improved. Suggested directions for improvement are provided. (author)

  19. High power microwave generation from coaxial virtual cathode oscillator using graphite and velvet cathodes

    Science.gov (United States)

    Menon, Rakhee; Roy, Amitava; Singh, S. K.; Mitra, S.; Sharma, Vishnu; Kumar, Senthil; Sharma, Archana; Nagesh, K. V.; Mittal, K. C.; Chakravarthy, D. P.

    2010-05-01

    High power microwave (HPM) generation studies were carried out in KALI-5000 pulse power system. The intense relativistic electron beam was utilized to generate HPMs using a coaxial virtual cathode oscillator. The typical electron beam parameters were 350 kV, 25 kA, and 100 ns, with a few hundreds of ampere per centimeter square current density. Microwaves were generated with graphite and polymer velvet cathode at various diode voltage, current, and accelerating gaps. A horn antenna setup with diode detector and attenuators was used to measure the microwave power. It was observed that the microwave power increases with the diode voltage and current and reduces with the accelerating gap. It was found that both the peak power and width of the microwave pulse is larger for the velvet cathode compared to the graphite cathode. In a coaxial vircator, velvet cathode is superior to the graphite cathode due to its shorter turn on time and better electron beam uniformity.

  20. Management and protection system for superconducting tokamak

    Science.gov (United States)

    Juszczyk, B.; Wojenski, A.; Zienkiewicz, P.; Kasprowicz, G.; Pozniak, K.; Romaniuk, R.

    2015-09-01

    This paper describes system for a diagnostics of a high-voltage power supply section of tokamaks. System is designed to assure reliability and safety of power supply subsystems. It is divided into two main components: remote and local. Remote part is located near tokamak, whereas local part can be localised away from the tokamak area. The remote side consists of custom, standalone devices. On the other hand, the local device is based on the uTCA.4 architecture. Components are connected with an optic fibre over a link-layer protocol which provides high throughput, low latency and transmission redundancy. All main operations ie. data processing, transmission etc. are performed on the FPGA devices. At the local side there is one device treated as a master device. It implements sort of a routing table which connects consecutive system inputs and outputs. It also provides possibility for some user defined data processing. This document contains general system overview, short description of hardware used in the project and gateware implementation.

  1. Quality-safety management and protective systems for SPES

    International Nuclear Information System (INIS)

    SPES (Selective Production of Exotic Species) is a project for the realization of a radioactive ion beam facility at Legnaro National Laboratory (Italy). An high degree of reliability in the Protective System must be achieved to prevent hazardous situations for operators, population and the surrounding environment. A Quality and Safety Management System (QSMS) is going to be realized. In this work we will present QSMS general structure, functions and goals. We will then focus our attention on the Access Control and Dose monitoring systems which are the key features of the SPES Protective System in the framework of the QSMS. (authors)

  2. Fire protection system operating experience review for fusion applications

    International Nuclear Information System (INIS)

    This report presents a review of fire protection system operating experiences from particle accelerator, fusion experiment, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of fire protection system component failure rates and fire accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with these systems are discussed, including spurious operation. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor

  3. Advanced Neutron Source reactor control and plant protection systems design

    International Nuclear Information System (INIS)

    This paper describes the reactor control and plant protection systems' conceptual design of the Advanced Neutron Source (ANS). The Plant Instrumentation, Control, and Data Systems and the Reactor Instrumentation and Control System of the ANS are planned as an integrated digital system with a hierarchical, distributed control structure of qualified redundant subsystems and a hybrid digital/analog protection system to achieve the necessary fast response for critical parameters. Data networks transfer information between systems for control, display, and recording. Protection is accomplished by the rapid insertion of negative reactivity with control rods or other reactivity mechanisms to shut down the fission process and reduce heat generation in the fuel. The shutdown system is designed for high functional reliability by use of conservative design features and a high degree of redundance and independence to guard against single failures. Two independent reactivity control systems of different design principles are provided, and each system has multiple independent rods or subsystems to provide appropriate margin for malfunctions such as stuck rods or other single failures. Each system is capable of maintaining the reactor in a cold shutdown condition independently of the functioning of the other system. A highly reliable, redundant channel control system is used not only to achieve high availability of the reactor, but also to reduce challenges to the protection system by maintaining important plant parameters within appropriate limits. The control system has a number of contingency features to maintain acceptable, off-normal conditions in spite of limited control or plant component failures thereby further reducing protection system challenges

  4. A Fall Protection System for High-Rise Construction

    Directory of Open Access Journals (Sweden)

    Haluk Çeçen

    2013-01-01

    Full Text Available In construction industry, the number of fatal and nonfatal occupational injuries is higher than other industries. Among causes of these accidents, “falls” play a key role. This situation reveals the importance for carrying out research in fall protection systems. In this paper, a practical, economical, and functional fall protection system is introduced. Following determination and evaluation of existing solutions, weekly brainstorming meetings were held among the responsible project staff (general coordinator, project coordinator, project manager, site manager, and health and safety manager. As a result of these meetings, design criteria were developed. Based on these criteria, the fall protection system for high-rise construction (FPSFHC was developed which satisfied all the specified design criteria. Required materials were procured from local dealers. In this paper, criteria used in design and details of the final design are presented. Field performance of the system is evaluated, and recommendations for further development and standardization of the system are added.

  5. Land system reform should protect farmers’ interests

    Institute of Scientific and Technical Information of China (English)

    刘守英

    2009-01-01

    |Editorial Note|Land has become an issue of increasing social concern as demand continues to surge in the midst of economic development,urbanization and industrialization.The crux of the issue is the land regime. China has a unique dualistic land regime under which the land market has not been well developed.Based on a review and commentary of the existing land polices,this article elaborates on the deficiencies inherent in China’s dualistic land rights system and land market and offers policy recommendations for promoting land system reform and market development.This study will help us gain an in-depth understanding of the problems in China’s land regime.

  6. Cooling system with automated seasonal freeze protection

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Levi A.; Chu, Richard C.; David, Milnes P.; Ellsworth, Jr., Michael J.; Iyengar, Madhusudan K.; Simons, Robert E.; Singh, Prabjit; Zhang, Jing

    2016-05-24

    An automated multi-fluid cooling system and method are provided for cooling an electronic component(s). The cooling system includes a coolant loop, a coolant tank, multiple valves, and a controller. The coolant loop is at least partially exposed to outdoor ambient air temperature(s) during normal operation, and the coolant tank includes first and second reservoirs containing first and second fluids, respectively. The first fluid freezes at a lower temperature than the second, the second fluid has superior cooling properties compared with the first, and the two fluids are soluble. The multiple valves are controllable to selectively couple the first or second fluid into the coolant in the coolant loop, wherein the coolant includes at least the second fluid. The controller automatically controls the valves to vary first fluid concentration level in the coolant loop based on historical, current, or anticipated outdoor air ambient temperature(s) for a time of year.

  7. Mechanistic Insight in the Function of Phosphite Additives for Protection of LiNi 0.5 Co 0.2 Mn 0.3 O 2 Cathode in High Voltage Li-Ion Cells

    Energy Technology Data Exchange (ETDEWEB)

    He, Meinan; Su, Chi-Cheung; Peebles, Cameron; Feng, Zhenxing; Connell, Justin G.; Liao, Chen; Wang, Yan; Shkrob, Ilya A.; Zhang, Zhengcheng

    2016-05-11

    Triethlylphosphite (TEP) and tris(2,2,2-trifluoroethyl) phosphite (TTFP) have been evaluated as electrolyte additives for high-voltage Li-ion battery cells using a Ni-rich layered cathode material LiNi0.5Co0.2Mn0.3O2 (NCM523) and the conventional carbonate electrolyte. The repeated charge/discharge cycling for cells containing 1 wt% of these additives was performed using an NCM523/graphite full cell operated at the voltage window from 3.0 to 4.6 V. During the initial charge process, these additives decompose on the cathode surface at a lower oxidation potential than the baseline electrolyte. Impedance spectroscopy and post-test analyses indicate the formation of protective coatings by both additives on the cathode surface that prevent oxidative breakdown of the electrolyte. However, only TTFP containing cells demonstrate the improved capacity retention and Coulombic efficiency. For TEP, the protective coating is also formed, but low Li+ ion mobility through the interphase layer results in inferior performance. These observations are rationalized through the inhibition of electrocatalytic centers present on the cathode surface and the formation of organophosphate deposits isolating the cathode surface from the electrolyte. The difference between the two phosphites clearly originates in the different properties of the resulting phosphate coatings, which may be in Li+ ion conductivity through such materials.

  8. Protective, Modular Wave Power Generation System

    Energy Technology Data Exchange (ETDEWEB)

    Vvedensky, Jane M.; Park, Robert Y.

    2012-11-27

    The concept of small wave energy conversion modules that can be built into large, scalable arrays, in the same vein as solar panels, has been developed. This innovation lends itself to an organic business and development model, and enables the use of large-run manufacturing technology to reduce system costs. The first prototype module has been built to full-scale, and tested in a laboratory wave channel. The device has been shown to generate electricity and dissipate wave energy. Improvements need to be made to the electrical generator and a demonstration of an array of modules should be made in natural conditions.

  9. Advanced worker protection system. Topical report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Myers, J.

    1995-07-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system, maintenance, and dramatically improve worker productivity through longer duration work cycles.

  10. Experiencies of corrosion and corrosion protection in seawater-cooling systems in the Nordic countries

    International Nuclear Information System (INIS)

    This report summarizes the experience of the corrosion resistance of pumps, heat exchangers, valves, and pipings in different seawater-cooling system. For pumps and heat exchangers the experience has been so extensive that a clear picture of todays status can be given. Owing to more scanty data concerning valves and pipes the survey of the corrosion in these components is less well substantiated. The most common pumps in the cooling systems of power stations are vertically extended shaft pumps. To counteract corrosion on column and casing with organic surface coating and on stainless steel shafts and impellers under shutdown conditions, these should be provided with internal and external cathodic protection. The experience of tin and aluminium bronzes in impellers and shafts in such pumps has been so poor - erosion and cavitaion damage - that a change has usually been made to preferentially ferritic-austenitic Mo-alloyd stainless steels. The combination of stainless steel/Ni-Resist 2 D has been found unsatisfactory owing to the occurrence of galvanic corrosion on the latter material. For heat exchangers, titanium has proved to be far and away the best choice. In the optimal blanket solution for a titanium heat exchangers the tubes are seal-welded to tube sheets of explosion-bonded titanium clad steel. For retubing of old condensers a similar procedure with tubes of high-alloy stainless steel in tube sheets of stainless clad steel is of economic interest. The effect of chlorination of the cooling water, however, remains to be clarified before such a procedure can be unreservedly recommended. Pipings of rubber-lined carbon steel or with thick coatings of solvent-free opoxy resin have shown very good corrosion resistance. Tar-epoxy-resin-coated pipes, however, should usually be provided with internal cathodic protection. Cement-lined carbon steel pipes are used with varying results in the offshore industry. Recently, however, pipes of the high slloy stainless steel

  11. Reactor regulating and protection system for a light water reactor

    International Nuclear Information System (INIS)

    Microprocessor based systems are developed for reactor regulation and protection of LWR. A triple modular redundancy approach is followed for the design of this system. This system is functionally partitioned into two sub-systems - Reactor Regulating System (RRS) and Reactor Trip Logic System (RTLS). RRS controls the reactor power as per demand and RTLS generates the reactor trip on abnormal process conditions. This paper describes the details of RRS and RTLS system architecture and fault tolerant and fail-safe features used in the system design. (author)

  12. WAVELETS AND ITS APPLICATIONS OF POWER SYSTEM PROTECTION

    OpenAIRE

    ÖZGÖNENEL, Okan; ÖZBİLGİN, Güven; KOCAMAN, Çağrı

    2010-01-01

    ABSTRACT In this work, a new digital protection  algorithm is developed for the power transformer which is the most important and expensive element in a power system. Due to their different sizes and varieties, relaying for power transformers differs from situation to situation. Transformer  protection algorithms, that have been developed so far, have proved their efficiency and computational ability. Using several windowing techniques cause significant delay for relay operation. Du...

  13. Innovative Impact Protection and Monitoring System for Composite Pressure Vessels

    OpenAIRE

    Kopperud, Paul Andreas

    2015-01-01

    Impact behavior and resistance of composite structures are difficult to predict. For composite pressure vessels, where failure can be fatal, impact protection and detection is particularly important. This thesis aims to render high pressure composite vessels safer to use with regards to impact. Three main objectives were identified; Firstly, finding an effective impact protection method and material. Secondly, developing a low cost impact detection system. Lastly, find an approach to estimate...

  14. A Framework for Evaluating Privacy Protection of Authentication Systems

    OpenAIRE

    Nakamura, Toru; Inenaga, Shunsuke; Ikeda, Daisuke; Baba, Kensuke; Yasuura, Hiroto

    2008-01-01

    Authentication plays a central role in a variety of social infrastructures such as access control or e-money. Not only should authentication systems be convenient, practical and secure, but also they are often required to protect users’ privacy. In this paper, we present an authentication framework for which identifiability, anonymity, linkability and unlinkability are well defined. Using our framework, we are able to evaluate and compare privacy protection properties of various authenticatio...

  15. Motor drive chassis for the plutonium protection system

    International Nuclear Information System (INIS)

    A motor drive chassis has been developed for use in the Plutonium Protection System. Rotation of the desired carrousel in a secure storage module is controlled by this chassis which supplies the power and drive pulses required by the carrousel motor. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Physical Protection Program

  16. Social Protection Systems in Latin America and the Caribbean: Colombia

    OpenAIRE

    Lucía Mina

    2014-01-01

    Social protection tends to revolve around the labour market, social security and social welfare. In Colombia, these issues are characterised by social disarticulation, both at the level of institutional capacity, as well as between supply and demand. In the early 21st century, the social protection system began to adopt a social risk management approach, understood as a set of public policies to reduce vulnerability and improve the quality of life of Colombians, especially among the most unpr...

  17. Adoption of digital safety protection system in Japan

    International Nuclear Information System (INIS)

    The application of micro-processor-based digital controllers has been widely propagated among various industries in recent years. While in the nuclear power plant industry, the application of them has also been expanding gradually starting from non-safety related systems, taking advantage of their reliability and maintainability over the conventional analog devices. Based on the careful study of the feasibility of digital controllers to the safety protection system, the Tokyo Electric Power Company proposed on May 1989 the adoption of digital controllers to the safety protection system in the Application for Permission of Establishment of Kashiwazaki-Kariwa units 6 and 7 (ABWR-1350Mwe each). MITI, Ministry of International Trade and Industry, the Japanese regulatory body for electric power generating facilities, had approved this application after careful review. This paper describes a series of supporting activities leading to the MITI's approval of the digital safety protection system and the MITI's licensing activities. (author)

  18. Railway automatic safety protection system based on GPS

    Directory of Open Access Journals (Sweden)

    Fu Hai Juan

    2016-01-01

    Full Text Available The automatic protection system of railway safety is designed for the railway construction workers to protect alarm, and the safety protection device by using GPS satellite positioning system to acquire location information of the operating point, through the CTC/TDCS system and computer monitoring system for the running of the train position and the arithmetic distance. Achieving timely and continuously forecasts about the distance of the train which is apart from the operating point to prompt the voice alarm of the approaching train. Using digital technology to realize the function of the traditional analog interphone, eliminates the quality problems of the call. With the GSM-R, mobile wireless transmission channel and terminal technology, it overcomes the restrictions of the analog interphone which influenced by communication distance and more problems of blind areas. Finally to achieve practical, convenient, applicable and adaptable design goals.

  19. Information support systems for cultural heritage protection against flooding

    Science.gov (United States)

    Nedvedova, K.; Pergl, R.

    2015-08-01

    The goal of this paper is to present use of different kind of software applications to create complex support system for protection of cultural heritage against flooding. The project is very complex and it tries to cover the whole area of the problem from prevention to liquidation of aftermath effects. We used GIS for mapping the risk areas, ontology systems for vulnerability assessment application and the BORM method (Business Object Relation Modelling) for flood protection system planning guide. Those modern technologies helped us to gather a lot of information in one place and provide the knowledge to the broad audience.

  20. Cold Vacuum Drying facility fire protection system design description

    International Nuclear Information System (INIS)

    This document describes the Cold Vacuum Drying Facility (CVDF) fire protection system (FPS). The FPS provides fire detection, suppression, and loss limitation for the CVDF structure, personnel, and in-process spent nuclear fuel. The system provides, along with supporting interfacing systems, detection, alarm, and activation instrumentation and controls, distributive piping system, isolation valves, and materials and controls to limit combustibles and the associated fire loadings

  1. Cyclotron resonance in a cathode ray tube

    International Nuclear Information System (INIS)

    Absorption of the RF energy by the electron beam in a cathode ray tube due to the cyclotron resonance is described. The cathode ray tube is placed within a Helmholtz coils system supplied by a sawtooth current generator. In order to generate RF field and to detect RF absorption a gate dip-meter equipped with a FET transistor is used. The bias voltage variations of the FET transistors as a function of the magnetic field are recorded. The operating point of the cathode ray tube has been chosen so that the relaxation oscillations of the detection system can be observed. (authors)

  2. Automatic coordination of protection devices in distribution system

    International Nuclear Information System (INIS)

    Among the several components of distribution systems, protection devices present a fundamental importance, since they aim at keeping the physical integrity not only of the system equipment, but also of the electricians' team and the population in general. The existing tools today in the market that carry out the making of protection studies basically draw curves, and need direct user's interference for the protection devices adjustment and coordination analyses of selectivity, being susceptible to the user's mistakes and not always considering the best technical and economical application. In Brazil, the correct application of the protection devices demand a high amount of time, being extremely laborious due to the great number of devices (around 200 devices), besides the very dynamic behaviour of distribution networks and the need for constant system expansion. This article presents a computational tool developed with the objective of automatically determining the adjustments of all protection devices in the distribution networks to obtain the best technical application, optimizing its performance and making easier protection studies. (author)

  3. A Westinghouse designed distributed mircroprocessor based protection and control system

    International Nuclear Information System (INIS)

    For approximately five years, Westinghouse has been involved in the design and licensing of a distributed microprocessor based system for the protection and control of a pressurized water reactor nuclear steam supply system. A 'top-down' design methodology was used, in which the system global performance objectives were specified, followed by increasingly more detailed design specifications which ultimately decomposed the system into its basic hardware and software elements. The design process and design decisions were influenced by the recognition that the final product would have to be verified to ensure its capability to perform the safety-related functions of a class 1E protection system. The verification process mirrored the design process except that it was 'bottom-up' and thus started with the basic elements and worked upwards through the system in increasingly complex blocks. A number of areas which are of interest in a distributed system are disucssed, with emphasis on two systems. The first, the Integrated Protection System is primarily responsible for processing signals from field mounted sensors to provide for reactor trips and the initiation of the Engineered Safety Features. The Integrated Control System, which is organized in a parallel manner, processes other sensor signals and generates the necessary analog and on-off signals to maintain the plant parameters within specified limits. Points covered include system structure, systems partitioning strategies, communications techniques, software design concepts, reliability and maintainability, commercial component availability, interference susceptibility, licensing issues, and applicability. (LL)

  4. Generalization of mathematical model of reliability of the complex Protection object - control and protection system

    International Nuclear Information System (INIS)

    Different control criteria are often used for system reliability improvement. Nowadays this feature isn't taken into account in analysis of reactor and NPP safety systems as a result of absence of appropriate mathematic models. In the paper it is shown that taking into account mentioned above features allows to obtain more precise values of reliability indices rather than in a case of assumption that different control criteria of protection channels are independent

  5. Cathodic disbonding of organic coatings on submerged steel

    Energy Technology Data Exchange (ETDEWEB)

    Knudsen, Ole oeystein

    1998-12-31

    In offshore oil production, submerged steel structures are commonly protected by an organic coating in combination with cathodic protection. The main advantage is that the coating decreases the current demand for cathodic protection. But the coating degrades with time. This thesis studies one of the most important mechanisms for coating degradation in seawater, cathodic disbonding. Seven commercial coatings and two model coatings with various pigmentations have been studied. Parameter studies, microscopy and studies of free films were used in the mechanism investigations. Exposure to simulated North Sea conditions was used in the performance studies. The effect of aluminium and glass barrier pigments on cathodic disbonding was investigated. The mechanism for the effect of the aluminium pigments on cathodic disbonding was also investigated. The transport of charge and oxygen to the steel/coating interface during cathodic disbonding was studied for two epoxy coatings. Cathodic disbonding, blistering and current demand for cathodic protection was measured for nine commercial coatings for submerged steel structures, using the ASTM-G8 standard test and a long term test under simulated North Sea conditions. The relevance of the ASTM-G8 test as a prequalification test was evaluated. 171 refs., 40 figs., 6 tabs.

  6. Management information system applied to radiation protection services

    Energy Technology Data Exchange (ETDEWEB)

    Grossi, Pablo Andrade; Souza, Leonardo Soares de; Figueiredo, Geraldo Magela; Figueiredo, Arthur, E-mail: pabloag@cdtn.br, E-mail: lss@cdtn.br, E-mail: gmf@cdtn.br, E-mail: arthurqof@gmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    An effective management information system based on technology, information and people is necessary to improve the safety on all processes and operations subjected to radiation risks. The complex and multisource information flux from all radiation protection activities on nuclear organizations requires a robust tool/system to highlight the strengths and weaknesses and identify behaviors and trends on the activities requiring radiation protection programs. Those organized and processed data are useful to reach a successful management and to support the human decision-making on nuclear organization. This paper presents recent improvements on a management information system based on the radiation protection directives and regulations from Brazilian regulatory body. This radiation protection control system is applied to any radiation protection services and research institutes subjected to Brazilian nuclear regulation and is a powerful tool for continuous management, not only indicating how the health and safety activities are going, but why they are not going as well as planned showing up the critical points. (author)

  7. THE PRACTISE OF CHILD PROTECTION SYSTEMS IN FOREIGN

    Directory of Open Access Journals (Sweden)

    Sychrová Adriana

    2012-01-01

    Full Text Available In most European countries and the U.S.A. the process of transformation of the child protection system has started. It can be characterized by deinstitutionalisation, restructuring of residential care, the strengthening of preventive measures and alternative care. The most typical is the effective programmes to strenghtes and expand foster care. In most countries strong child protection systems exist. On the one hand there is family support model and on the other hand there is the child protection model. Both of them are based on children rights but they use different strategies. Welfare services and family support must be at the core of prevention strategies for vulnerable children and children in care. This article dealswith some of the fundamental issues concerning social intervention and care of vulnerable children in foreign countries. The purpose is to describe the actual problems of systems, changing of minds and using contemporary practises of residential care and family type care as foster care is.

  8. A secure steganography for privacy protection in healthcare system.

    Science.gov (United States)

    Liu, Jing; Tang, Guangming; Sun, Yifeng

    2013-04-01

    Private data in healthcare system require confidentiality protection while transmitting. Steganography is the art of concealing data into a cover media for conveying messages confidentially. In this paper, we propose a steganographic method which can provide private data in medical system with very secure protection. In our method, a cover image is first mapped into a 1D pixels sequence by Hilbert filling curve and then divided into non-overlapping embedding units with three consecutive pixels. We use adaptive pixel pair match (APPM) method to embed digits in the pixel value differences (PVD) of the three pixels and the base of embedded digits is dependent on the differences among the three pixels. By solving an optimization problem, minimal distortion of the pixel ternaries caused by data embedding can be obtained. The experimental results show our method is more suitable to privacy protection of healthcare system than prior steganographic works. PMID:23321975

  9. Phase equilibria, thermodynamic and electrochemical properties of cathodes in lithium ion batteries based on the Li–(Co, Ni)–O system

    OpenAIRE

    Chang, Keke

    2013-01-01

    Currently, LiCoO2 is widely used as cathode in lithium ion batteries for “small” applications (e.g., laptops and cell phones). However, the relatively high cost and safety problems limit its applications in electric vehicles. Partial substitution of Co with other transition metals, such as Ni and Mn, can lower costs and improve battery performance and safety. The present dissertation aims at studying the Li–(Co,Ni)–O system using CALPHAD (calculation of phase diagrams) modeling and ab initio ...

  10. The system of radiation protection applied in Czechoslovakia

    International Nuclear Information System (INIS)

    The concept of the radiation protection system (RPS) that has been gradually set up in Czechoslovakia was based on the Recommendations of the International Commission on Radiological Protection. A decree defines the responsibility, as well as more detailed obligations of organizations using radiation sources, as regards the protection of workers as well as the public, and includes the obligation to ensure an effective monitoring of radiation situations and of doses to persons. Expert supervision of adherence to the radiation protection regulations is carried out by the Hygiene Service, a public health inspection service whose activities in radiation protection are set up at the regional and central level. In each region there is a Radiation Hygiene Department with qualified personnel and appropriate instrumentation for the evaluation of exposure situations which may occur in the region. The departments supervise all workplaces using radiation sources, prepare binding recommendations to the regional health offices regarding the design of laboratories, licenses for the use of radiation sources, and approval for the start or termination of a practice. Central components of the structure directing the RPS in the country are the chief health officers of Bohemia and Slovakia and their expert bases - the Radiation Hygiene Centres at the Institutes for Hygiene and Epidemiology in both Republics. Apart from preparation or radiation protection standards and regulations, guidance as to methods and quality assurance for the work of regional Departments, these expert bases play a co-ordinating role in the system of handling radiation accidents and providing medical assistance to overexposed people. The Radiation Hygiene Centre in Prague acts as a centre for the radiation monitoring network in cases of nuclear accidents, in which the regional stations, nuclear power plants, research institutes and other bodies participate. A system of technical services in radiation protection

  11. Practical Approach on Lightning and Grounding Protection System

    Directory of Open Access Journals (Sweden)

    Shan Jose Varghese

    2015-04-01

    Full Text Available Lightning Protection and Grounding of Electrical and Mechanical equipment’s for the Protection of the Human Beings, Structure of the building and equipment protection, safe working of the Worker at Industry as per my latest practical knowledge in the site environment in extreme climatic condition of low lying areas of the Gulf Region in the challenging projects. All the conductor calculation, Lightning Risk Factor calculations, all the system information regarding the level of protection required for site are mentioned in this paper. Lightning, Electrical and Mechanical Equipment surge protection is the one of the major complicated protection in the World as it is unpredictable. As both can cause major causality and damage the building and equipment’s in the path way surroundings. As per the world status there are more number of causalities as occurred due to Lighting and short circuit errors. Grounding of the electrical and mechanical equipment can have low potential difference hence will not cause much damage as the surge current has easy path to the ground. Complete information regarding the Lightning and Surge arrestor system is illustrated as per my findings while working as the Design Electrical Engineer

  12. Reliability of Substation Protection System Based on IEC61850

    Institute of Scientific and Technical Information of China (English)

    XIONG Xiaofu; YU Jun; LIU Xiaofang; SHEN Zhijan

    2008-01-01

    Although the new technology of protection and automation system of substation based on IEC61850 standard has developed rapidly in China, reliability measures depending on this tech- nology need to be further researched. By taking advantage of convenient information sharing, two kinds of new schemes, shared backup protection unit (SBPU) and signal backup (SB), have been proposed to solve the failure problem of protective devices and current/voltage transducers respec- tively, and the working principle of these two schemes are also described. Furthermore, the key technologies of on-line diagnosis of protective devices' failure and on-line status diagnosis of op- tical or electronic current/voltage transducers to realize the two schemes are proposed.

  13. Physical protection of hardware and software. Linking access control systems with operational computer systems

    International Nuclear Information System (INIS)

    The existence and use of software and networks have generated another possibility for perpetrators to influence systems in nuclear facilities or to prepare malevolent acts. Data security has become an element of physical protection plans, not as an end in itself but as a means to achieve physical protection objectives. Physical protection measures are additional measures, which become necessary when other measures that have to be taken (e.g. in compliance with international standards) are insufficient to prevent a hazard to the protection goals through data manipulation by software and hardware. In planning or assessing data protection measures for the purpose of physical protection, it is necessary to differentiate between applications which can, if manipulated, directly endanger the protection goals. The importance of software protection is growing. In particular, because of ageing of components, the existing instrumentation and control systems with their fixed wiring and discrete elements will have to be updated. Computerized access control systems play an eminent role in the physical protection of a nuclear facility. Therefore, most systems are operated as islands. The paper shows that linking of certain systems with other computer systems is possible without inadmissible drawbacks for the physical protection level. It is shown by means of the example of linking together the computer networks of access control, health physics, the flexitime system, the key administration and the operational management system that such linking of systems in nuclear facilities had hidden advantages for all participants

  14. Localization of equipment for digital plant protection system

    International Nuclear Information System (INIS)

    The objective of this project lies on the development of design requirements, establishment of structure and manufacture procedures, development of the software verification and validation(V and V) techniques of the digital plant protection system. The functional requirements based on the analog protection system and digital design requirements are introduced, the processor and system bus for safety grade equipment are selected and the interface requirements and the design specification have been developed in order to manufacture the quick prototype of the digital plant protection system. The selection guidelines of parts, software development and coding and testing for digital plant protection system have been performed through manufacturing the quick prototype based on the developed design specification. For the software verification and validation, the software review plan and techniques of verification and validation have been researched. The digital validation system is developed in order to verify the quick prototype. The digital design requirements are reviewed by the software safety plan and V and V plans. The formal methods for verifying the safety-grade software are researched, then the methodology of formal analysis and testing have been developed

  15. Localization of equipment for digital plant protection system

    Energy Technology Data Exchange (ETDEWEB)

    Koo, I. S.; Park, H. Y.; Lee, C. K. and others

    2000-10-01

    The objective of this project lies on the development of design requirements, establishment of structure and manufacture procedures, development of the software verification and validation(V and V) techniques of the digital plant protection system. The functional requirements based on the analog protection system and digital design requirements are introduced, the processor and system bus for safety grade equipment are selected and the interface requirements and the design specification have been developed in order to manufacture the quick prototype of the digital plant protection system. The selection guidelines of parts, software development and coding and testing for digital plant protection system have been performed through manufacturing the quick prototype based on the developed design specification. For the software verification and validation, the software review plan and techniques of verification and validation have been researched. The digital validation system is developed in order to verify the quick prototype. The digital design requirements are reviewed by the software safety plan and V and V plans. The formal methods for verifying the safety-grade software are researched, then the methodology of formal analysis and testing have been developed.

  16. Seismic protection of secondary systems in nuclear power plant facilities

    International Nuclear Information System (INIS)

    Numerical models of a sample nuclear power plant (NPP) reactor building, both conventionally constructed and equipped with seismic protective systems are analyzed for both Safe Shutdown and Beyond-Design-Basis earthquake shaking at two coastal sites in the United States. Seismic demands on secondary systems are established for the conventional and seismically isolated NPPs. The reductions in secondary-system acceleration and deformation demands afforded by the isolation systems are identified. The impact of isolation system choice on the response of the key secondary systems is presented. (authors)

  17. Random Vibration of Space Shuttle Weather Protection Systems

    Directory of Open Access Journals (Sweden)

    Isaac Elishakoff

    1995-01-01

    Full Text Available The article deals with random vibrations of the space shuttle weather protection systems. The excitation model represents a fit to the measured experimental data. The cross-spectral density is given as a convex combination of three exponential functions. It is shown that for the type of loading considered, the Bernoulli-Euler theory cannot be used as a simplified approach, and the structure will be more properly modeled as a Timoshenko beam. Use of the simple Bernoulli-Euler theory may result in an error of about 50% in determining the mean-square value of the bending moment in the weather protection system.

  18. The role of privacy protection in healthcare information systems adoption.

    Science.gov (United States)

    Hsu, Chien-Lung; Lee, Ming-Ren; Su, Chien-Hui

    2013-10-01

    Privacy protection is an important issue and challenge in healthcare information systems (HISs). Recently, some privacy-enhanced HISs are proposed. Users' privacy perception, intention, and attitude might affect the adoption of such systems. This paper aims to propose a privacy-enhanced HIS framework and investigate the role of privacy protection in HISs adoption. In the proposed framework, privacy protection, access control, and secure transmission modules are designed to enhance the privacy protection of a HIS. An experimental privacy-enhanced HIS is also implemented. Furthermore, we proposed a research model extending the unified theory of acceptance and use of technology by considering perceived security and information security literacy and then investigate user adoption of a privacy-enhanced HIS. The experimental results and analyses showed that user adoption of a privacy-enhanced HIS is directly affected by social influence, performance expectancy, facilitating conditions, and perceived security. Perceived security has a mediating effect between information security literacy and user adoption. This study proposes several implications for research and practice to improve designing, development, and promotion of a good healthcare information system with privacy protection. PMID:24014266

  19. Improved Dispenser Cathodes

    Science.gov (United States)

    Ives, R. Lawrence; Falce, Lou

    2006-01-01

    Variations in emission current from dispenser cathodes can be caused by variations in temperature and work function over the surface. This paper described research to reduce these variations using improved mechanical designs and controlled porosity cathodes made from sintered tungsten wires. The program goal is to reduce current emission variations to less than 5% over the surface of magnetron injection guns operating temperature limited.

  20. Joint force protection advanced security system (JFPASS) "the future of force protection: integrate and automate"

    Science.gov (United States)

    Lama, Carlos E.; Fagan, Joe E.

    2009-09-01

    The United States Department of Defense (DoD) defines 'force protection' as "preventive measures taken to mitigate hostile actions against DoD personnel (to include family members), resources, facilities, and critical information." Advanced technologies enable significant improvements in automating and distributing situation awareness, optimizing operator time, and improving sustainability, which enhance protection and lower costs. The JFPASS Joint Capability Technology Demonstration (JCTD) demonstrates a force protection environment that combines physical security and Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) defense through the application of integrated command and control and data fusion. The JFPASS JCTD provides a layered approach to force protection by integrating traditional sensors used in physical security, such as video cameras, battlefield surveillance radars, unmanned and unattended ground sensors. The optimization of human participation and automation of processes is achieved by employment of unmanned ground vehicles, along with remotely operated lethal and less-than-lethal weapon systems. These capabilities are integrated via a tailorable, user-defined common operational picture display through a data fusion engine operating in the background. The combined systems automate the screening of alarms, manage the information displays, and provide assessment and response measures. The data fusion engine links disparate sensors and systems, and applies tailored logic to focus the assessment of events. It enables timely responses by providing the user with automated and semi-automated decision support tools. The JFPASS JCTD uses standard communication/data exchange protocols, which allow the system to incorporate future sensor technologies or communication networks, while maintaining the ability to communicate with legacy or existing systems.

  1. Active Wireless Temperature Sensors for Aerospace Thermal Protection Systems

    Science.gov (United States)

    Milos, Frank S.; Karunaratne, K.; Arnold, Jim (Technical Monitor)

    2002-01-01

    Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles in order to reduce life-cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to advance inspection and health management technologies for thermal protection systems. This paper summarizes a joint project between NASA Ames and Korteks to develop active wireless sensors that can be embedded in the thermal protection system to monitor sub-surface temperature histories. These devices are thermocouples integrated with radio-frequency identification circuitry to enable acquisition and non-contact communication of temperature data through aerospace thermal protection materials. Two generations of prototype sensors are discussed. The advanced prototype collects data from three type-k thermocouples attached to a 2.54-cm square integrated circuit.

  2. The evolution of the system of radition protection

    International Nuclear Information System (INIS)

    Shortly after the discovery of ionizing radiation just over one hundred years ago it became apparent that this type of radiation had the potential to cause harm to human health. So began the evolution of the system of radiation protection which has continued to this day. Radiation protection is a multi-factoral problem and requires input from a variety of disciplines such as physics, chemistry, biology and epidemiology. In order to develop a system of radiation protection there are three questions that need to be answered. What are the effects of ionizing radiation on human health, how can you measure and quantify levels of ionizing radiation exposure, and what useful recommendation can be made with regard to protection against this type of radiation? Over the last hundred there has been continual development of the system of radiation protection as new information became available and new measurement methodologies and techniques were developed. The first fifty years saw a concentration on acute and chronic health effects which resulted from the killing of large numbers of cells, whereas since the 1950s the emphasis has been on hereditary and carcinogenic effects that can damage a cell while not affecting its viability. For the first type of effects a clear line can usually be drawn between acceptable and unacceptable outcomes, however, for the second type of effects it is the probability of developing an outcome rather than the severity of the outcome that is proportional to exposure. This requires a subjective assessment on what is acceptable and consequently radiation protection recommendations, in particular dose limits, can not be so black and white in their application. While radiation protection will continue to develop as the science develops, we probably know more about how to quantify the effects of ionizing radiation than we do about many other carcinogens. The problem is that the public perception is that ionizing radiation is several orders of

  3. Respiratory protective device design using control system techniques

    Science.gov (United States)

    Burgess, W. A.; Yankovich, D.

    1972-01-01

    The feasibility of a control system analysis approach to provide a design base for respiratory protective devices is considered. A system design approach requires that all functions and components of the system be mathematically identified in a model of the RPD. The mathematical notations describe the operation of the components as closely as possible. The individual component mathematical descriptions are then combined to describe the complete RPD. Finally, analysis of the mathematical notation by control system theory is used to derive compensating component values that force the system to operate in a stable and predictable manner.

  4. New technology for reactor protection system of CAREM reactor

    International Nuclear Information System (INIS)

    The use of FPGA in safety functions in a nuclear power plant, increase the reliability of software based systems, without loose any of the function required by the supervision and control systems. In this work the architecture of a Reactor Protection System is described, it use four independent measurement channels in 2 oo 4 configuration, each channel is based on diverse approach in 1 oo 2 configuration, the reliability of this system is near the same than the hardwired logic, with full performance like software based system. (author)

  5. Electric probe diagnostics of the hollow cathode plasma jet system for TiO.sub.x./sub. thin films deposition

    Czech Academy of Sciences Publication Activity Database

    Virostko, Petr; Hubička, Zdeněk; Kment, Štěpán; Adámek, Petr; Jastrabík, Lubomír; Tichý, M.

    Praha : Institute of Plasma Physics AS CR, 2007 - (Schmidt, J.; Šimek, M.; Pekárek, S.; Prukner, V.), s. 783-786 ISBN 978-80-87026-01-4. [International conference on phenomena in ionized gases - ICPIG /28./. Praha (CZ), 15.07.2007-20.07.2007] R&D Projects: GA AV ČR KAN400720701; GA ČR GA202/06/0776 Institutional research plan: CEZ:AV0Z10100522 Keywords : probe diagnostics * Langmuir probe * hollow cathode * plasma jet Subject RIV: BL - Plasma and Gas Discharge Physics

  6. Some problem of emergency exposure medical system and radiation protection

    International Nuclear Information System (INIS)

    Fukushima nuclear accident was a complex disaster and then clarified some problem of emergency exposure medical system. This article described such problem and introduced nuclear emergency preparedness guidelines focusing on exposure medical matter. At the initial stage of the accident, 5 initial exposure medical organizations like the off-site center could not work at all. Secondary exposure medical organization was regional core hospital and had excessive medical loads. Third organizations dispatched exposure medical support teams to the site to rebuild the emergency exposure medical system. Emergency evacuation of patients and preventive use of stabilized iodine tablets should be well prepared. At radiation accidents, radiation protection measures should be chosen for exposure path and accident stage such as emergency exposure situation or existing exposure situation. Comprehensive standards for deterministic and probabilistic effects with relevant measure to prevent or minimize effects or reduce probabilistic risks were tabulated from IAEA documents for the reference. Emergency Action Level (EAL) and Operation Intervention Level (OIL) should be predetermined to start protective measures. Emergency was classified into three categories: Alert, site emergency and general emergency. Assuming general emergency, protective measures were considered for respective zones of PAZ (Precautionary Active Zone), UPZ (Urgent Protective action Planning Zone) and PPA (Plume Protection Planning Area, under consideration). (T. Tanaka)

  7. Fire protection system at the Juragua nuclear power plant, Cuba

    International Nuclear Information System (INIS)

    The paper describes the general fire protection system at the Juragua nuclear power plant in Cuba. The factors which led to the construction of the first nuclear power plant in Cuba and the planning of others in the near future are outlined. Reference is made to existing Cuban legislation on fire protection, particularly with regard to the protection of facilities which constitute a radiation hazard. Attention is drawn to the fact that, although Cuba does not have much experience in this area, considerable work has been done in a brief span of time on legislation, standardization and monitoring in nuclear facilities in order to guarantee safe operating conditions. The potential risk of fires at the Juragua plant under normal and accident conditions is analysed, and the technical and organizational measures required to minimize existing risks are discussed in the light of this analysis. The basis for determining the manpower and equipment needed by the plant's fire protection service is also defined. Finally, certain criteria concerning the special psychological and technical qualities required of personnel, as well as the necessary qualifications and training, are presented. The point is made that very little has been published at the international level on this subject and that it is a research area which deserves more attention. The serious, responsible attitude adopted in designing the plant's fire protection system, with a view to achieving optimum safety conditions during operation, is also highlighted. (author)

  8. The core protection computer system fitted in Grafenrheinfeld NPP

    International Nuclear Information System (INIS)

    This paper gives an overview of a four-train core protection computer system for KWU pressurized water reactors. Attention is focused on the methods used to ensure correct computer operation and correct results. Experience gained in trial operation is dealt with. Results of safety analysis of the hardware and the software verification work performed are discussed. (author)

  9. Assessment of fire protection systems in proscenium theaters

    Directory of Open Access Journals (Sweden)

    Jaewook Kwon

    2014-10-01

    Computational fluid dynamics (CFD has been utilized to examine fire conditions and to assess the effectiveness of the fire protection systems provided within a stage. The input data including representative theater dimensions, fuel loads, and fire scenarios have been determined by a survey of theater design professionals.

  10. Comparing electrochemical performance of transition metal silicate cathodes and chevrel phase Mo6S8 in the analogous rechargeable Mg-ion battery system

    Science.gov (United States)

    Chen, Xinzhi; Bleken, Francesca L.; Løvvik, Ole Martin; Vullum-Bruer, Fride

    2016-07-01

    Polyanion based silicate materials, MgMSiO4 (M = Fe, Mn, Co), previously reported to be promising cathode materials for Mg-ion batteries, have been re-examined. Both the sol-gel and molten salt methods are employed to synthesize MgMSiO4 composites. Mo6S8 is synthesized by a molten salt method combined with Cu leaching and investigated in the equivalent electrochemical system as a bench mark. Electrochemical measurements for Mo6S8 performed using the 2nd generation electrolyte show similar results to those reported in literature. Electrochemical performance of the silicate materials on the other hand, do not show the promising results previously reported. A thorough study of these published results are presented here, and compared to the current experimental data on the same material system. It appears that there are certain inconsistencies in the published results which cannot be explained. To further corroborate the present experimental results, atomic-scale calculations from first principles are performed, demonstrating that diffusion barriers are very high for Mg diffusion in MgMSiO4. In conclusion, MgMSiO4 (M = Fe, Mn, Co) olivine materials do not seem to be such good candidates for cathode materials in Mg-ion batteries as previously reported.

  11. A NEW CROWBAR SYSTEM FOR THE PROTECTION OF HIGH POWER GRIDDED TUBES AND MICROWAVE DEVICES

    International Nuclear Information System (INIS)

    As part of the electron cyclotron heating (ECH) facility upgrade at the DIII-D National Fusion Facility, two 8.4 MW modulator/regulator power systems were designed and constructed (Ref. 1). Each power system uses a high power tetrode to modulate and regulate the cathode voltage for two 1 MW-class 110 GHz gyrotrons (Ref. 2). A critical element in the power system is the fault energy divertor, or crowbar switch, that protects the tetrode and the gyrotrons in the event of an arc fault. Traditionally, mercury filled ignitron switches are used for this application, but it was desired to eliminate hazardous materials and improve overall switching performance. The new crowbar switch system was required to meet the following requirements: Operating voltage: -105 kVdc; Peak current (750 ms e-fold): 1.6 kA; Follow-on current: <1 kA (25 ms); Charge transfer per shot: <15 Cb; and Turn-on time: <1 (micro)s. The switch that was chosen for the new design is a low pressure deuterium filled device, called a metal-arc thyratron, manufactured by Marconi Applied Technologies (Ref. 3). In addition to the new crowbar switch assembly, improved fault signal processing circuitry was developed. This new circuitry uses fiber-optics for signal and trigger transmission and a complex programmable logic device for high speed signal and logic processing. Two generations of metal-arc thyratrons have been commissioned in the two ECH power systems constructed at DIII-D. In the first, the crowbar system performed extremely well, meeting all of the operating requirements and demonstrating its ability to protect a 36 gauge copper wire from fusing (energy let-through <10 J). However, after accumulating over 500 shots, the metal-arc thyratrons lost their ability to reliably hold-off voltage. This problem was solved by Marconi with a design modification of the thyratron electrodes. The second generation tubes were installed in the second ECH power system. The crowbar system was fully commissioned and all

  12. Operability of Space Station Freedom's meteoroid/debris protection system

    Science.gov (United States)

    Kahl, Maggie S.; Stokes, Jack W.

    1992-01-01

    The design of Space Station Freedom's external structure must not only protect the spacecraft from the hazardous environment, but also must be compatible with the extra vehicular activity system for assembly and maintenance. The external procedures for module support are utility connections, external orbital replaceable unit changeout, and maintenance of the meteoroid/debris shields and multilayer insulation. All of these interfaces require proper man-machine engineering to be compatible with the extra vehicular activity and manipulator systems. This paper discusses design solutions, including those provided for human interface, to the Space Station Freedom meteoroid/debris protection system. The system advantages and current access capabilities are illustrated through analysis of its configuration over the Space Station Freedom resource nodes and common modules, with emphasis on the cylindrical sections and endcones.

  13. Feasibility study on KSNP adaption of French digital protection system

    International Nuclear Information System (INIS)

    Upgrade of nuclear power plant I and c systems by using digital technology has been implemented to overcome the obsolescence of existing equipment and improve plant availability in many advanced countries. For upgrade of the Plant Protection System(PPS) based on conventional analog technology in the UCN 3 and 4 YGN 5 and 6, French modernized Digital Integrated Protection System(DIPS) with proven technology is reviewed and evaluated for the adaptability into PPS. This paper contains the results of feasibility study for the design of digital PPS using French DIPS technology. Based on the results of evaluations, the system architecture of digital PPS is designed and described. 12 refs., 3 figs. (author)

  14. System of nuclear power reactor protection using dynamic logic

    International Nuclear Information System (INIS)

    The aim of this work is the design of a Reactor Protection System (RPS) using dynamic logic as basic circuitry principle. This concept was developed to permit the electronic and eletromagnetic components employment in 'fail-safe' mode applied to automatic shutdown systems. 'Fail-safe' here means that a fail always yields a constant state that leads to a plant shutdown condition. So the normal condition of operation corresponds to an oscillating state response and the fail or abnormal condition to a static one. At present, almost all modern nuclear plant reactor protection systems use dynamic logic, just differing in the kind of technology employed in the construction of the system. In this work we define what technology best fits our necessities, setting out to design a RPS based on this philosophy. (author)

  15. Software reliability and safety in nuclear reactor protection systems

    International Nuclear Information System (INIS)

    Planning the development, use and regulation of computer systems in nuclear reactor protection systems in such a way as to enhance reliability and safety is a complex issue. This report is one of a series of reports from the Computer Safety and Reliability Group, Lawrence Livermore that investigates different aspects of computer software in reactor National Laboratory, that investigates different aspects of computer software in reactor protection systems. There are two central themes in the report, First, software considerations cannot be fully understood in isolation from computer hardware and application considerations. Second, the process of engineering reliability and safety into a computer system requires activities to be carried out throughout the software life cycle. The report discusses the many activities that can be carried out during the software life cycle to improve the safety and reliability of the resulting product. The viewpoint is primarily that of the assessor, or auditor

  16. Software reliability and safety in nuclear reactor protection systems

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, J.D. [Lawrence Livermore National Lab., CA (United States)

    1993-11-01

    Planning the development, use and regulation of computer systems in nuclear reactor protection systems in such a way as to enhance reliability and safety is a complex issue. This report is one of a series of reports from the Computer Safety and Reliability Group, Lawrence Livermore that investigates different aspects of computer software in reactor National Laboratory, that investigates different aspects of computer software in reactor protection systems. There are two central themes in the report, First, software considerations cannot be fully understood in isolation from computer hardware and application considerations. Second, the process of engineering reliability and safety into a computer system requires activities to be carried out throughout the software life cycle. The report discusses the many activities that can be carried out during the software life cycle to improve the safety and reliability of the resulting product. The viewpoint is primarily that of the assessor, or auditor.

  17. CLASSIFICATION OF THE MGR SUBSURFACE FIRE PROTECTION SYSTEM

    International Nuclear Information System (INIS)

    The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) subsurface fire protection system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998)

  18. CLASSIFICATION OF THE MGR WASTE HANDLING BUILDING FIRE PROTECTION SYSTEM

    International Nuclear Information System (INIS)

    The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) waste handling building fire protection system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998)

  19. Optimizations of Battery-Based Intrusion Protection Systems

    OpenAIRE

    Nelson, Theresa Michelle

    2008-01-01

    As time progresses, small mobile devices become more prevalent for both personal and industrial use, providing malicious network users with new and exciting venues for security exploits. Standard security applications, such as Norton Antivirus and MacAfee, require computing power, memory space, and operating system complexity that are not present in small mobile devices. Recently, the Battery-Sensing Intrusion Protection System (B-SIPS) was devised as a means to correct the inability of small...

  20. Software development for bistable module of SMART plant protection system

    International Nuclear Information System (INIS)

    Digitalized PPS(Plant Protection System) is going on development for SMART. The PPS consists of two different types of CPUs and DSP boards for the each functional processor modules of PPS. Software for the system has been progressed with teamwork of CASE TOOL to develop the reliable software. In this paper, we propose the software development method and show the examples for Bistable module through the functional analysis and the development of Structure Chart and M-Spec

  1. Dedicated monitoring and machinery protection systems on reciprocating compressors

    Energy Technology Data Exchange (ETDEWEB)

    Grande, Alvaro; Wenisch, Markus [Hoerbiger Ventilwerke GmbH and Co KG, Wien (Austria); Jacobs, Denis [HOERBIGER do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    Growing demands on reciprocating compressors (recips) in the process gas industry require particular solutions for machinery protection and performance monitoring systems. Compared to rotating equipment, monitoring systems for recips have to consider the special mechanical and physical characteristics, such as oscillating masses, variable vibration behaviour and varying operating conditions. Furthermore, they provide valuable information about the performance of cylinder related components allowing the operator the optimization of efficiency and availability, and therefore increase production. (author)

  2. Optimal channel utilization and service protection in cellular communication systems

    DEFF Research Database (Denmark)

    Iversen, Villy Bæk

    In mobile communications an efficient utilization of the channels is of great importance.In this paper we consider the basic principles for obtaining the maximum utilization, and we study strategies for obtaining these limits.In general a high degree of sharing is efficient, but requires service...... protection mechanisms for protecting services and subscriber groups.We study cellular systems with overlaid cells, and the effect of overlapping cells, and we show that by dynamic channel allocation we obtain a high utilization.The models are generalizations of the Erlang-B formula, and can be evaluated...

  3. Guidance for software safety planning in digital protection systems

    International Nuclear Information System (INIS)

    Real-time embedded software used in nuclear reactor protection systems is an area where software safety planning must be subject to highly rigorous and systematic analysis. Recently, the safety planning for safety-critical software systems is being recognized as the most important phase in the software life cycle and is currently leading to new regulatory positions and standards by the regulatory and the standardization organizations. The requirements for software of digital protection systems are described in such standards as, for example, the new Standard Review Plan, International Electrochemical Commission (IEC) 880 supplements, Institute of Electrical and Electronics Engineers (IEEE) Standard 1228-1994, IEEE Standard 7-4.3.2-1993, and International Atomic Energy Agency (IAEA) Safety Series No. 50-SG-D3 and D8 which are being updated. Most of them describe mandatory requirements, what shall be done, for safety-critical software. The vendors of software-based safety systems have developed their own work practices for developing the software. However, there has been much controversy between the licenser and the licensee over whether work practices satisfy regulatory requirements and whether the safety of a system developed by work practices is justified. We believe that the controversy is caused by a gap between the mandatory requirements (what) and the work practices (how). We have developed a guidance to fill such a gap, which can be useful to both licenser and licensee to justify the safety in the planning phase of software development for nuclear reactor protection systems

  4. Vision-based pedestrian protection systems for intelligent vehicles

    CERN Document Server

    Geronimo, David

    2013-01-01

    Pedestrian Protection Systems (PPSs) are on-board systems aimed at detecting and tracking people in the surroundings of a vehicle in order to avoid potentially dangerous situations. These systems, together with other Advanced Driver Assistance Systems (ADAS) such as lane departure warning or adaptive cruise control, are one of the most promising ways to improve traffic safety. By the use of computer vision, cameras working either in the visible or infra-red spectra have been demonstrated as a reliable sensor to perform this task. Nevertheless, the variability of human's appearance, not only in

  5. Functional description of the dynamically operating reactor protection system

    International Nuclear Information System (INIS)

    For detection of accidents and irritation of engineering safety systems there is required a reactor protection system meeting highest demands for reliability. These demands are met by redundant systems where all faults are automatically recorded or detected by means of testing. Clear design of circuits, good maintenance properties, and extensive inspections and acceptance tests of subassemblies and entire circuit will also contribute to make the system reliable. In detail there is presented: functional disposition, analog, logic and relay (generating output signals) sections, types of subassemblies, elementary diagrams. (orig.)

  6. Preliminary Validation and Verification Plan for CAREM Reactor Protection System

    International Nuclear Information System (INIS)

    The purpose of this paper, is to present a preliminary validation and verification plan for a particular architecture proposed for the CAREM reactor protection system with software modules (computer based system).These software modules can be either own design systems or systems based in commercial modules such as programmable logic controllers (PLC) redundant of last generation.During this study, it was seen that this plan can also be used as a validation and verification plan of commercial products (COTS, commercial off the shelf) and/or smart transmitters.The software life cycle proposed and its features are presented, and also the advantages of the preliminary validation and verification plan

  7. Evaluation report Sandia Plutonium Protection System operational demonstration

    International Nuclear Information System (INIS)

    Sandia Laboratories of Albuquerque, New Mexico, has developed an advanced plutonium storage system. The system provides protection for and accountability of material in storage and controls personnel access to storage areas. This storage system has been installed and operationally demonstrated at the Rockwell Hanford Operations Z-Plant facility. All demonstration transactions were performed by Z-Plant personnel. The demonstration was carried out to evaluate the system operation using special nuclear material in an operational environment. This document is the evaluation report of the operational demonstration

  8. Dependable Design Flow for Protection Systems using Programmable Logic Devices

    CERN Document Server

    Kwiatkowski, M

    2011-01-01

    Programmable Logic Devices (PLD) such as Field Programmable Gate Arrays (FPGA) are becoming more prevalent in protection and safety-related electronic systems. When employing such programmable logic devices, extra care and attention needs to be taken. The final synthesis result, used to generate the bit-stream to program the device, must be shown to meet the design’s requirements. This paper describes how to maximize confidence using techniques such as Formal Methods, exhaustive Hardware Description Language (HDL) code simulation and hardware testing. An example is given for one of the critical functions of the Safe Machine Parameters (SMP) system, used in the protection of the Large Hadron Collider (LHC) at CERN. CERN is also working towards an adaptation of the IEC- 61508 lifecycle designed for Machine Protection Systems (MPS), and the High Energy Physics environment, implementation of a protection function in FPGA code is only one small step of this lifecycle. The ultimate aim of this project is to cre...

  9. Direct surface modification of high-voltage LiCoO2 cathodes by UV-cured nanothickness poly(ethylene glycol diacrylate) gel polymer electrolytes

    International Nuclear Information System (INIS)

    Highlights: • Direct surface modification of high-voltage LCO cathode by UV-cured PEGDA GPE. • Conformal PEGDA nanocoating layer is formed on LCO surface. • Preformed architecture of LCO cathode is not disrupted by PEGDA coating layer. • PEGDA-LCO cathode improves high-voltage cycling performance and thermal stability. • PEGDA nanocoating layer serves as a new ion-conductive protection film. -- Abstract: In the development of high-voltage lithium-ion batteries, unwanted interfacial side reactions between delithiated cathode materials and liquid electrolytes pose a formidable challenge that needs to be urgently resolved. In this study, as a simple and effective approach to improve cell performance and thermal stability of high-voltage cells, we demonstrate direct surface modification of a cathode by UV-cured nanothickness poly(ethylene glycol diacrylate) (PEGDA) gel polymer electrolyte (GPE). Herein, the UV-crosslinking of EGDA oligomers is conducted directly on as-formed cathode (LiCoO2 (LCO) is chosen as a model system), instead of application to LCO powders. This unusual coating process allows the successful formation of the conformal PEGDA nanocoating layer on the LCO surface without disrupting the preformed physical architecture of the LCO cathode (specifically, electronic networks and porous structure to be filled with liquid electrolyte). Owing to the structural novelty, the PEGDA-coated LCO cathode improves the cycling performance of high-voltage (=4.4 V) cells and suppresses the exothermic reaction between the delithiated LCO and liquid electrolyte, as compared to the pristine LCO cathode. These results underline that the conformal PEDGDA nanocoating layer proposed herein acts as a new ion-conductive protection film that effectively mitigates the undesired interfacial side reactions

  10. Intelligent vehicle electrical power supply system with central coordinated protection

    Science.gov (United States)

    Yang, Diange; Kong, Weiwei; Li, Bing; Lian, Xiaomin

    2016-05-01

    The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect; electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle's battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle's power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.

  11. Multi Agent System Based Adaptive Protection for Dispersed Generation Integrated Distribution Systems

    DEFF Research Database (Denmark)

    Liu, Leo; Rather, Zakir Hussain; Bak, Claus Leth; Chen, Zhe

    2013-01-01

    allowing islanded operation of distribution systems necessitates the adoption of adaptive protection methods for distribution systems. In order to improve the reliability and selectivity of protection for such kind of distribution systems, a coordinative adaptive protection based on multi agent system (MAS......The increasing penetration of dispersed generation (DG) brings challenges to conventional protection approaches of distribution system, mainly due to bi-directional power flow and variable fault current contribution from different generation technology-based DG units. Moreover, the trend of......) is proposed. The adaptive protection intelligently adopts suitable settings for the variation of fault current from diversified DG units. Furthermore, the structure of mobile MAS with additional flexibility is capable of adapting the changes of system topology in a short period, e.g. radial...

  12. Transparent System for Digital Media Copyright Protection in Mobile Business

    Institute of Scientific and Technical Information of China (English)

    YANG Cheng; ZHANG Lihe; WANG Yongbin; LIU Jianbo

    2006-01-01

    At present, in mobile business, the secure environment in the terminal of users has not been embedded, many cryptology-based methods can not be directly used to protect the copyright of digital media. Under this situation, a transparent system based on watermark for digital right management and digital copyright protection is proposed in this paper. The transparent system is called WDRM (watermark-based digital rights management) and transparent to users. Its core is WDRM Agent. In this paper, system inner model and procession are designed in detail at first, including the registration, the downloading, the super distribution, and the cooperation. Because the watermark embedding and the extraction algorithms are the kernel in this architecture, we also discuss how to choose and design the algorithms. Then we establish a package for all algorithms in WDRM Agent.

  13. Development and assessment of advanced reactor core protection system

    International Nuclear Information System (INIS)

    An advanced core protection system for a pressurized water reactor, Reactor Core Protection System (RCOPS), was developed by adopting a high performance hardware platform and optimal system configuration. The functional algorithms of the core protection system were also improved to enhance the plant availability by reducing unnecessary reactor trips and increasing operational margin. The RCOPS consists of four independent safety channels providing a two-out-of-four trip logic. The reliability analysis using the reliability block diagram method showed the unavailability of the RCOPS to be lower than the conventional system. The failure mode and effects analysis demonstrated that the RCOPS does not lose its intended safety functions for most failures. New algorithms for the RCOPS functional design were implemented in order to avoid unnecessary reactor trips by providing auxiliary pre-trip alarms and signal validation logic for the control rod position. The new algorithms in the RCOPS were verified by comparing the RCOPS calculations with reference results. The new thermal margin algorithm for the RCOPS was expected to increase the operational margin to the limit for Departure from Nucleate Boiling Ratio (DNBR) by approximately 1%. (author)

  14. Real-time information and processing system for radiation protection

    International Nuclear Information System (INIS)

    The real-time information and processing system has as main task to record, collect, process and transmit the radiation level and weather data, being proposed for radiation protection, environmental monitoring around nuclear facilities and for civil defence. Such a system can offer information in order to provide mapping, data base, modelling and communication and to assess the consequences of nuclear accidents. The system incorporates a number of stationary or mobile radiation monitoring equipment, weather parameter measuring station, a GIS-based information processing center and the communication network, all running on a real-time operating system. It provides the automatic data collection on-line and off-line, remote diagnostic, advanced presentation techniques, including a graphically oriented executive support, which has the ability to respond to an emergency by geographical representation of the hazard zones on the map.The system can be integrated into national or international environmental monitoring systems, being based on local intelligent measuring and transmission units, simultaneous processing and data presentation using a real-time operating system for PC and geographical information system (GIS). Such an integrated system is composed of independent applications operating under the same computer, which is capable to improve the protection of the population and decision makers efforts, updating the remote GIS data base. All information can be managed directly from the map by multilevel data retrieving and presentation by using on-line dynamic evolution of the events, environment information, evacuation optimization, image and voice processing

  15. A Method for Monitoring Deposition at a Solid Cathode in an Electrorefiner for a Two-Species System Using Electrode Potentials

    Energy Technology Data Exchange (ETDEWEB)

    D.S. Rappleye; M.-S. Yim; M.F. Simpson; R.M. Cumberland

    2013-10-01

    Currently, process monitoring of spent nuclear fuel electrorefining relies upon sampling and destructive analysis methods coupled with extrapolative thermodynamic process models for non-interrupted operations. Corrections to those models are performed infrequently, jeopardizing both the control of the process and safeguarding of nuclear material. Furthermore, the timeliness of obtaining the results is inadequate for application of international safeguards protocol. Alternatively, a system that dynamically utilizes electrical data such as electrode potentials and cell current can hypothetically be used to achieve real-time process monitoring and more robust control as well as improved safeguards. Efforts to develop an advanced model of the electrorefiner to date have focused on a forward modeling approach by using feed and salt compositions to determine the product composition, cell current and electrode potential response. Alternatively, an inverse model was developed, and reported here, to predict the product deposition rates on a cathode using the cell current, cathode potential, and fundamental relations of electrochemistry. The model was applied to the following cases: pure uranium deposition, co-deposition of uranium and plutonium, and co-deposition of uranium and zirconium. The deposition rates predicted by the inverse model were compared to those of a forward model, ERAD.

  16. In-situ observation of a dendrite growth in an aqueous condition and a uranium deposition into a liquid cadmium cathode in an electrowinning system

    International Nuclear Information System (INIS)

    A zinc-gallium system was setup to observe the growth process of dendrites and to compare the performance of the stirrers which would prevent a dendrite formation. In a no-stirring condition, zinc was easily deposited on a liquid gallium cathode in the form of dendrites. It was difficult for a paddle stirrer to directly fracture the zinc dendrites to fine particles. However, a harrow stirrer was observed to fracture the dendrite to some extent at high speeds. Not only their rotation speed but also the length of their blades needed to be properly adjusted to enhance their performance. In the uranium-cadmium experiment, the diffusion coefficient of the uranium species was obtained by the cyclic voltammetry method, which is around 1 x 10-5 cm2/s. In a no-stirring condition, most of the uranium deposited at the current densities of 35, 100 and 200 mA/cm2 did not sink into the liquid cadmium cathode

  17. Optimization of working cathode position in sleeve-type bioelectrochemical system with inner chamber/outer chamber for azo dye treatment.

    Science.gov (United States)

    Kong, Fanying; Wang, Aijie; Ren, Hong-Yu

    2015-12-01

    In this study, the optimization of working cathode position in sleeve-type bioelectrochemical system (BES) was evaluated with inner/outer chamber for azo dye decolorization. Results showed that the working position in outer chamber performed better with decolorization efficiencies of 97.8 ± 2.1% (7h) and 94.0 ± 2.3% (16 h) than that in inner chamber as the volume ratio Vcathode:Vanode=1:1 and 3:1, respectively. The current and electrochemical impedance spectroscopy (EIS) analysis indicated that the proton/electron transfer and anolyte diffusion could be improved using outer chamber as working position. The decolorization with increased volume ratio could be further improved through the strategy of increasing substrate concentration, which would provide enough electrons and decrease diffusion resistance, further improving the whole performance with increased outer cathode volume. It has the great potential in sleeve-type configuration application and would create more challenges for process optimization and maintenance. PMID:26409856

  18. Advanced Control and Protection system Design Methods for Modular HTGRs

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Sydney J [ORNL; Wilson Jr, Thomas L [ORNL; Wood, Richard Thomas [ORNL

    2012-06-01

    The project supported the Nuclear Regulatory Commission (NRC) in identifying and evaluating the regulatory implications concerning the control and protection systems proposed for use in the Department of Energy's (DOE) Next-Generation Nuclear Plant (NGNP). The NGNP, using modular high-temperature gas-cooled reactor (HTGR) technology, is to provide commercial industries with electricity and high-temperature process heat for industrial processes such as hydrogen production. Process heat temperatures range from 700 to 950 C, and for the upper range of these operation temperatures, the modular HTGR is sometimes referred to as the Very High Temperature Reactor or VHTR. Initial NGNP designs are for operation in the lower temperature range. The defining safety characteristic of the modular HTGR is that its primary defense against serious accidents is to be achieved through its inherent properties of the fuel and core. Because of its strong negative temperature coefficient of reactivity and the capability of the fuel to withstand high temperatures, fast-acting active safety systems or prompt operator actions should not be required to prevent significant fuel failure and fission product release. The plant is designed such that its inherent features should provide adequate protection despite operational errors or equipment failure. Figure 1 shows an example modular HTGR layout (prismatic core version), where its inlet coolant enters the reactor vessel at the bottom, traversing up the sides to the top plenum, down-flow through an annular core, and exiting from the lower plenum (hot duct). This research provided NRC staff with (a) insights and knowledge about the control and protection systems for the NGNP and VHTR, (b) information on the technologies/approaches under consideration for use in the reactor and process heat applications, (c) guidelines for the design of highly integrated control rooms, (d) consideration for modeling of control and protection system designs

  19. "TPSX: Thermal Protection System Expert and Material Property Database"

    Science.gov (United States)

    Squire, Thomas H.; Milos, Frank S.; Rasky, Daniel J. (Technical Monitor)

    1997-01-01

    The Thermal Protection Branch at NASA Ames Research Center has developed a computer program for storing, organizing, and accessing information about thermal protection materials. The program, called Thermal Protection Systems Expert and Material Property Database, or TPSX, is available for the Microsoft Windows operating system. An "on-line" version is also accessible on the World Wide Web. TPSX is designed to be a high-quality source for TPS material properties presented in a convenient, easily accessible form for use by engineers and researchers in the field of high-speed vehicle design. Data can be displayed and printed in several formats. An information window displays a brief description of the material with properties at standard pressure and temperature. A spread sheet window displays complete, detailed property information. Properties which are a function of temperature and/or pressure can be displayed as graphs. In any display the data can be converted from English to SI units with the click of a button. Two material databases included with TPSX are: 1) materials used and/or developed by the Thermal Protection Branch at NASA Ames Research Center, and 2) a database compiled by NASA Johnson Space Center 9JSC). The Ames database contains over 60 advanced TPS materials including flexible blankets, rigid ceramic tiles, and ultra-high temperature ceramics. The JSC database contains over 130 insulative and structural materials. The Ames database is periodically updated and expanded as required to include newly developed materials and material property refinements.

  20. Hybrid Plasma Reactor/Filter for Transportable Collective Protection Systems

    Energy Technology Data Exchange (ETDEWEB)

    Josephson, Gary B.; Tonkyn, Russell G.; Frye, J. G.; Riley, Brian J.; Rappe, Kenneth G.

    2011-04-06

    Pacific Northwest National Laboratory (PNNL) has performed an assessment of a Hybrid Plasma/Filter system as an alternative to conventional methods for collective protection. The key premise of the hybrid system is to couple a nonthermal plasma (NTP) reactor with reactive adsorption to provide a broader envelope of protection than can be provided through a single-solution approach. The first step uses highly reactive species (e.g. oxygen radicals, hydroxyl radicals, etc.) created in a nonthermal plasma (NTP) reactor to destroy the majority (~75% - 90%) of an incoming threat. Following the NTP reactor an O3 reactor/filter uses the O3 created in the NTP reactor to further destroy the remaining organic materials. This report summarizes the laboratory development of the Hybrid Plasma Reactor/Filter to protect against a ‘worst-case’ simulant, methyl bromide (CH3Br), and presents a preliminary engineering assessment of the technology to Joint Expeditionary Collective Protection performance specifications for chemical vapor air purification technologies.

  1. Protection of the Lifeless Environment in the Solar System

    Science.gov (United States)

    Almar, I.

    The main concern of planetary protection policy is how to protect the (hypothetical) extraterrestrial life against contamination and back-contamination. There is almost no interest in the preservation of the existing lifeless surfaces of extraterrestrial bodies, although some planetary transformation plans (in order to exploit hypothetical resources) were made public a long time ago. It should be remembered that planetary environments are practically unchanged since ages and damage caused by any human intervention would be irreversible. Our intention is not to prevent any commercial utilization of Solar System resources, but to make space exploration and exploitation of resources a controlled and well planned endeavor. The three main issues connected with the protection of the lifeless space environment are the following: 1/ The scientific aspect: a limited, well defined initiative to select by scientific investigation areas and objects of highest scientific priority on different celestial bodies. 2/ The legal aspect: to start the drafting of a declaration of principles supporting the protection of selected areas and objects on celestial bodies with a solid surface. It might evolve into an international legal instrument or treaty in order to limit the "free-for-all" intervention and use of Solar System resources. 3/ The societal aspect: to initiate a large scale discussion on the possible "ethical values" of the lifeless environment.

  2. ETV Program Report: Coatings for Wastewater Collection Systems - Protective Liner Systems, Inc., Epoxy Mastic, PLS-614

    Science.gov (United States)

    The Protective Liner Systems International, Inc. Epoxy Mastic PLS-614 coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Material and T...

  3. Evolution of reactor monitoring and protection systems for PWR

    International Nuclear Information System (INIS)

    This paper presents the evolution of the reactor protection systems and of the reactor monitoring systems for PWR since the initial design in the Fessenheim plant to the latest development for the EPR (European pressurized reactor). The features of both systems for the different kinds of PWR operating in France: 900 MWe, 1300 MWe and N4, are reviewed. The expected development of powerful micro-processors for computation, for data analysis and data storage will make possible in a near future the monitoring on a 3-dimensional basis and on a continuous manner, of the nuclear power released in the core. (A.C.)

  4. Development of a model representing systems protected against research*

    Science.gov (United States)

    Styugin, M.

    2016-04-01

    The research described herein presents a method of modeling information systems with dynamic parameters. The model includes elements with discrete internal states and agents, which can act in the system by modifying states of the system’s elements. The research has two objectives aimed at protection against research, which are as follows: inadmissibility for the system to transfer into some specific states and invisibility of actions taken by the agents. The present paper establishes stable secure states and proves algorithmic insolubility of Problem 1 in its general case.

  5. Westinghouse Reactor Protection System Unavailability, 1984-1995

    Energy Technology Data Exchange (ETDEWEB)

    C. D. Gentillon; D. Marksberry (USNRC); D. Rasmuson; M. B. Calley; S. A. Eide; T. Wierman (INEEL)

    1999-08-01

    An analysis was performed of the safety-related performance of the reactor protection system (RPS) at U.S. Westinghouse commercial reactors during the period 1984 through 1995. RPS operational data were collected from the Nuclear Plant Reliability Data System and Licensee Event Reports. A risk-based analysis was performed on the data to estimate the observed unavailability of the RPS, based on a fault tree model of the system. Results were compared with existing unavailability estimates from Individual Plant Examinations and other reports.

  6. Westinghouse Reactor Protection System Unavailability, 1984--1995

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Steven Arvid; Calley, Michael Brennan; Gentillon, Cynthia Ann; Wierman, Thomas Edward; Rasmuson, D.; Marksberry, D.

    1999-08-01

    An analysis was performed of the safety-related performance of the reactor protection system (RPS) at U. S. Westinghouse commercial reactors during the period 1984 through 1995. RPS operational data were collected from the Nuclear Plant Reliability Data System and Licensee Event Reports. A risk-based analysis was performed on the data to estimate the observed unavailability of the RPS, based on a fault tree model of the system. Results were compared with existing unavailability estimates from Individual Plant Examinations and other reports.

  7. Fail-safe computer-based plant protection systems

    International Nuclear Information System (INIS)

    A fail-safe mode of operation for computers used in nuclear reactor protection systems was first evolved in the UK for application to a sodium cooled fast reactor. The fail-safe properties of both the hardware and the software were achieved by permanently connecting test signals to some of the multiplexed inputs. This results in an unambiguous data pattern, each time the inputs are sequentially scanned by the multiplexer. The ''test inputs'' simulate transient excursions beyond defined safe limits. The alternating response of the trip algorithms to the ''out-of-limits'' test signals and the normal plant measurements is recognised by hardwired pattern recognition logic external to the computer system. For more general application to plant protection systems, a ''Test Signal Generator'' (TSG) is used to compute and generate test signals derived from prevailing operational conditions. The TSG, from its knowledge of the sensitivity of the trip algorithm to each of the input variables, generates a ''test disturbance'' which is superimposed upon each variable in turn, to simulate a transient excursion beyond the safe limits. The ''tripped'' status yielded by the trip algorithm when using data from a ''disturbed'' input forms part of a pattern determined by the order in which the disturbances are applied to the multiplexer inputs. The data pattern formed by the interleaved test disturbances is again recognised by logic external to the protection system's computers. This fail-safe mode of operation of computer-based protection systems provides a powerful defence against common-mode failure. It also reduces the importance of software verification in the licensing procedure. (author)

  8. Reactor protection system with automatic self-testing and diagnostic

    International Nuclear Information System (INIS)

    A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically ''identical'' values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic. 16 figs

  9. Diagnostics of N2 Ar plasma mixture excited in a 13.56 MHz hollow cathode discharge system: application to remote plasma treatment of polyamide surface

    Science.gov (United States)

    Saloum, S.; Naddaf, M.; Alkhaled, B.

    2008-02-01

    N2-x% Ar plasma gas mixture, generated in a hollow cathode RF discharge system, has been characterized by both optical emission spectroscopy (OES) and double Langmuir probe, as a function of experimental parameters: total pressure (5-33 Pa), and different fractions of argon (7 polyamide (PA) surface interaction, in the remote plasma zone, has been studied through OES analysis during plasma treatment of PA to monitor the possible emissions due to the polymer etching. An increase in atomic nitrogen line (672.3 nm) intensity is obtained, atomic carbon line (833.52 nm) and the band emission (0-0) from the CN (B 2Σ+-X 2Σ+) violet system were observed. The PA surface modification has been confirmed through the improvement of its hydrophilic character as the water contact angle measured after the plasma treatment significantly decreased.

  10. Nanostructured sulfur cathodes

    KAUST Repository

    Yang, Yuan

    2013-01-01

    Rechargeable Li/S batteries have attracted significant attention lately due to their high specific energy and low cost. They are promising candidates for applications, including portable electronics, electric vehicles and grid-level energy storage. However, poor cycle life and low power capability are major technical obstacles. Various nanostructured sulfur cathodes have been developed to address these issues, as they provide greater resistance to pulverization, faster reaction kinetics and better trapping of soluble polysulfides. In this review, recent developments on nanostructured sulfur cathodes and mechanisms behind their operation are presented and discussed. Moreover, progress on novel characterization of sulfur cathodes is also summarized, as it has deepened the understanding of sulfur cathodes and will guide further rational design of sulfur electrodes. © 2013 The Royal Society of Chemistry.

  11. Cathodes - Technological review

    International Nuclear Information System (INIS)

    Lithium cobalt oxide (LiCoO2) was already used in the first commercialized Li-ion battery by SONY in 1990. Still, it is the most frequently used cathode material nowadays. However, LiCoO2 is intrinsically unstable in the charged state, especially at elevated temperatures and in the overcharged state causing volume changes and transport limitation for high power batteries. In this paper, some technological aspects with large impact on cell performance from the cathode material point of view will be reviewed. At first it will be focused on the degradation processes and life-time mechanisms of the cathode material LiCoO2. Electrochemical and structural results on commercial Li-ion batteries recorded during the cycling will be discussed. Thereafter, advanced nanomaterials for new cathode materials will be presented

  12. Safety evaluation of the KNICS digital reactor protection system

    International Nuclear Information System (INIS)

    Korean Nuclear I and C System (KNICS) project, a national research program for developing a safety-class digital system, has designed a new reactor protection system (RPS). The usage of digital equipment in a safety critical application increases the importance of a risk evaluation since microprocessors and software technologies make the digital system very complex and their unavailability is hard to quantify. This paper addresses the safety evaluation of the KNICS RPS in consideration of the several technical concerns of a safety modeling for a digital system. We also present the fault-tree modeling technique and the risk evaluation results. A fault-tree model which includes the common cause failure events, the coverage of a fault-tolerant mechanism and the software failure event is developed. Based on the minimal cut sets of the model, we discuss the system unavailability of the newly developed design of the KNICS RPS

  13. Plutonium Protection System (PPS). Volume 2. Hardware description. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Miyoshi, D.S.

    1979-05-01

    The Plutonium Protection System (PPS) is an integrated safeguards system developed by Sandia Laboratories for the Department of Energy, Office of Safeguards and Security. The system is designed to demonstrate and test concepts for the improved safeguarding of plutonium. Volume 2 of the PPS final report describes the hardware elements of the system. The major areas containing hardware elements are the vault, where plutonium is stored, the packaging room, where plutonium is packaged into Container Modules, the Security Operations Center, which controls movement of personnel, the Material Accountability Center, which maintains the system data base, and the Material Operations Center, which monitors the operating procedures in the system. References are made to documents in which details of the hardware items can be found.

  14. Fire protection of photovoltaic systems; Brandschutz an Photovoltaikanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Reil, Florian; Vaassen, Willi [TUEV Rheinland Energie und Umwelt GmbH, Koeln (Germany)

    2011-10-15

    The fire protection for photovoltaic systems features need for action. The research project of the TUeV Rheinland AG (Cologne, Federal Republic of Germany) in conjunction with the Fraunhofer Institute for Solar Energy Systems ISE (Freiburg, Federal Republic of Germany) and the professional fire department Munich (Munich, Federal Republic of Germany) offers a neutral and factual portal for the exchange of related topics. Preventive fire protection and the fire fighting of photovoltaic power plants always have to be seen as a network of different possibilities and paths. This network has to be based on quality products, professional installation and adapted structural and technical measures. The results of the project are transparently and consciously open with all stakeholders and made available to the German photovoltaic industry.

  15. Game theoretic analysis of physical protection system design

    International Nuclear Information System (INIS)

    The physical protection system (PPS) of a fictional small modular reactor (SMR) facility have been modeled as a platform for a game theoretic approach to security decision analysis. To demonstrate the game theoretic approach, a rational adversary with complete knowledge of the facility has been modeled attempting a sabotage attack. The adversary adjusts his decisions in response to investments made by the defender to enhance the security measures. This can lead to a conservative physical protection system design. Since defender upgrades were limited by a budget, cost benefit analysis may be conducted upon security upgrades. One approach to cost benefit analysis is the efficient frontier, which depicts the reduction in expected consequence per incremental increase in the security budget

  16. Lightning protection of flap system for wind turbine blades

    DEFF Research Database (Denmark)

    Candela Garolera, Anna; Madsen, Søren Find

    The aim of this PhD project was to investigate the behaviour of a Controllable Rubber Trailing Edge Flap (CRTEF) in a wind turbine blade when it is exposed to lightning discharges, and find the best technical solution to protect the CRTEF and the controlling system against lightning, based on the...... results of simulation models and high voltage tests. Wind turbines are a common target of lightning due to their height and location, and blades are the components most exposed to direct discharges. Protecting the blades against lightning is specially challenging, mainly because of the combination of...... insulating, semi-conductive and conductive materials in their structure. For this reason, the installation of a CRTEF in a blade requires a careful assessment of risks related to lightning strikes. The study of the lightning effects in the CRTEF system comprised the analysis of the discharge attachment, the...

  17. Design of motorcycle rider protection systems using numerical techniques.

    Science.gov (United States)

    Miralbes, R

    2013-10-01

    The goal of this paper is the development of a design methodology, based on the use of finite elements numerical tools and dummies in order to study the damages and injuries that appear during a motorcyclist collision against a motorcyclist protection system (MPS). According to the existing regulation, a Hybrid III dummy FEM model has been used as a starting point and some modifications have been included. For instance a new finite element helmet model has been developed and later added to the dummy model. Moreover, some structural elements affecting the simulation results such as the connecting bolts or the ground have been adequately modeled. Finally there have been analyzed diverse types of current motorcyclists protection systems, for which it has been made a comparative numerical-experiment analysis to validate the numerical results and the methodology used. PMID:23792610

  18. Protection study of a diagnostic system for electron beam at the output of an accelerator

    International Nuclear Information System (INIS)

    The aim of this work is the determination of the conception of a protection system dedicated to protect a diagnostic system in the CNSTN. According to this study, the suitable material for the protection against the electrons in the plexiglas and the supermalloy to protect the future diagnostic system against the magnetic field. (Author)

  19. The Challenges of Credible Thermal Protection System Reliability Quantification

    Science.gov (United States)

    Green, Lawrence L.

    2013-01-01

    The paper discusses several of the challenges associated with developing a credible reliability estimate for a human-rated crew capsule thermal protection system. The process of developing such a credible estimate is subject to the quantification, modeling and propagation of numerous uncertainties within a probabilistic analysis. The development of specific investment recommendations, to improve the reliability prediction, among various potential testing and programmatic options is then accomplished through Bayesian analysis.

  20. Protecting sensitive systems and data in an open agency

    Science.gov (United States)

    Hunt, Douglas B.; Tompkins, Frederick G.

    1987-01-01

    This paper focuses on the policy and definitional issues associated with providing adequate and reasonable levels of protection for sensitive systems and data in an agency whose basic charter mandates the open sharing of information and transfer of technology into the market economy. An information model based on current Federal regulatory issuances is presented. A scheme for determining sensitivity levels, based on a categorization taxonomy,is provided.

  1. Promising freeze protection alternatives in solar domestic hot water systems

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.E.

    1997-12-31

    Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without resorting to a heat exchanger. Commonly, collectors are made of rigid copper tubes separated by copper or aluminum fins. Cracking damage can occur when water is allowed to freeze and expand inside the non compliant tubes. The possibility of making collectors out of an elastic material was investigated and shown to be effective. Since unlike copper, elastomers typically have low thermal conductivities, the standard collector performance prediction equations do not apply. Modified thermal performance prediction equations were developed which can be used for both low and high thermal conductivity materials to provide accurate predictions within a limited range of plate geometries. An elastomeric collector plate was then designed and shown to have comparable performance to a copper plate collector whose aperture area is approximately 33% smaller. Another options for providing freeze protection to an SDHW system is to turn it off during the winter. Choosing a three-season operating period means two things. First, the system will have different optimums such as slope and collector area. Second, the wintertime solar energy incident on the collector is unavailable for meeting a heating load. However, the system`s heat exchanger becomes unnecessary and removing it increases the amount of energy that arrives at the storage tank during those periods in which the system is operating.

  2. Physical Protection System Upgrades - Optimizing for Performance and Cost

    International Nuclear Information System (INIS)

    CPA--Cost and Performance Analysis--is an architecture that supports analysis of physical protection systems and upgrade options. ASSESS (Analytic System and Software for Evaluating Security Systems), a tool for evaluating performance of physical protection systems, currently forms the cornerstone for evaluating detection probabilities and delay times of the system. Cost and performance data are offered to the decision-maker at the systems level and to technologists at the path-element level. A new optimization engine has been attached to the CPA methodology to automate analyses of many combinations (portfolios) of technologies. That engine controls a new analysis sequencer that automatically modifies ASSESS PPS files (facility descriptions), automatically invokes ASSESS Outsider analysis and then saves results for post-processing. Users can constrain the search to an upper bound on total cost, to a lower bound on level of performance, or to include specific technologies or technology types. This process has been applied to a set of technology development proposals to identify those portfolios that provide the most improvement in physical security for the lowest cost to install, operate and maintain at a baseline facility

  3. Unequal error protection system for robust video transmission

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With the development of multimedia communication services, robust video transmission over wireless environment poses many challenges. A new UEP_ BTC _ STBC _ OFDM system is proposed to provide unequal error protection for the source coded video stream in dispersive fading channel. The scheme concatenates the Block Turbo Code (BTC) with the Space-Time Block Code (STBC) for an OFDM system.With the proposed system, both the good error correcting capability of BTC and the concurrent large diversity gain characteristic of STBC can be achieved simultaneously with low encoding and decoding complexity. Furthermore, by combining with the data partition of H. 264 and different BTC codes, this system can guarantee high QoS control of video transmission. Simulation result shows that the proposed system outperforms other reported schemes and has good performance of video transmission.

  4. Iris-based authentication system with template protection and renewability

    Science.gov (United States)

    Ercole, Chiara; Campisi, Patrizio; Neri, Alessandro

    2007-10-01

    Biometrics is the most emerging technology for automatic people authentication, nevertheless severe concerns raised about security of such systems and users' privacy. In case of malicious attacks toward one or more components of the authentication system, stolen biometric features cannot be replaced. This paper focuses on securing the enrollment database and the communication channel between such database and the matcher. In particular, a method is developed to protect the stored biometric templates, adapting the fuzzy commitment scheme to iris biometrics by exploiting error correction codes tailored on template discriminability. The aforementioned method allows template renewability applied to iris based authentication and guarantees high security performing the match in the encrypted domain.

  5. Structural evaluation of candidate space shuttle thermal protection systems

    Science.gov (United States)

    Burns, A. B.

    1972-01-01

    The characteristics and development of a lightweight reusable thermal protection system for the space shuttle are discussed. The test articles consisted of metallic substrates with upper surfaces covered with all-silica, reusable, surface insulation material. The material is processed in the form of tiles. The external surfaces of the tiles are provided with a coating system which consists of a borosilicate coating with a silicon carbide emittance agent and impregnation with a hydrophobic agent. The finished tiles are attached to the metal substrate by adhesive bonding. Charts and graphs of the properties of the material are provided.

  6. Model Based Cyber Security Analysis for Research Reactor Protection System

    International Nuclear Information System (INIS)

    The study on the qualitative risk due to cyber-attacks into research reactors was performed using bayesian Network (BN). This was motivated to solve the issues of cyber security raised due to digitalization of instrumentation and control (I and C) system. As a demonstrative example, we chose the reactor protection system (RPS) of research reactors. Two scenarios of cyber-attacks on RPS were analyzed to develop mitigation measures against vulnerabilities. The one is the 'insertion of reactor trip' and the other is the 'scram halt'. The six mitigation measures are developed for five vulnerability for these scenarios by getting the risk information from BN

  7. Development of plasma cathode electron guns

    Science.gov (United States)

    Oks, Efim M.; Schanin, Peter M.

    1999-05-01

    The status of experimental research and ongoing development of plasma cathode electron guns in recent years is reviewed, including some novel upgrades and applications to various technological fields. The attractiveness of this kind of e-gun is due to its capability of creating high current, broad or focused beams, both in pulsed and steady-state modes of operation. An important characteristic of the plasma cathode electron gun is the absence of a thermionic cathode, a feature which leads to long lifetime and reliable operation even in the presence of aggressive background gas media and at fore-vacuum gas pressure ranges such as achieved by mechanical pumps. Depending on the required beam parameters, different kinds of plasma discharge systems can be used in plasma cathode electron guns, such as vacuum arcs, constricted gaseous arcs, hollow cathode glows, and two kinds of discharges in crossed E×B fields: Penning and magnetron. At the present time, plasma cathode electron guns provide beams with transverse dimension from fractional millimeter up to about one meter, beam current from microamperes to kiloamperes, beam current density up to about 100 A/cm2, pulse duration from nanoseconds to dc, and electron energy from several keV to hundreds of keV. Applications include electron beam melting and welding, surface treatment, plasma chemistry, radiation technologies, laser pumping, microwave generation, and more.

  8. Safety aspect of digital reactor protection system in Japan

    International Nuclear Information System (INIS)

    It was early in 1980's that the digital controllers were first applied to nuclear power plant in japan. After that, their application area had been expanding gradually, reaching to the overall integrated digital system including the safety system in Kashiwazaki-Kariwa units 6 and 7. The software for computer-based systems has been produced using the graphical language ''POL'' in Japanese nuclear power plants. It is the fundamental principle that the reliability of the software should be assured through the properly managed quality assurance. The POL-based system is fitted to this principle. In applying POL-based systems to safety system, the MITI, Ministry of International Trade and Industry, identified the licensing issues as the regulatory body, while the utilities had developed the digital technology feasible to the safety application. Through the activities, a specific industrial design guide for the software important to safety was established and the adequacy of the technology was certified through the demonstration tests of the integrated system. In the safety examination of the digital reactor protection system of K-6/7, the application of POL were approved. The POL-based systems in nuclear power plants were successful design and production process of the POL-based systems. This paper describes the activities in licensing and maintaining the computer-based systems by the utilities and manufacturers as well as the MITI. (author)

  9. Detection and Protection Against Intrusions on Smart Grid Systems

    Directory of Open Access Journals (Sweden)

    Ata Arvani

    2015-05-01

    Full Text Available The wide area monitoring of power systems is implemented at a central control center to coordinate the actions of local controllers. Phasor measurement units (PMUs are used for the collection of data in real time for the smart grid energy systems. Intrusion detection and cyber security of network are important requirements for maintaining the integrity of wide area monitoring systems. The intrusion detection methods analyze the measurement data to detect any possible cyber attacks on the operation of smart grid systems. In this paper, the model-based and signal-based intrusion detection methods are investigated to detect the presence of malicious data. The chi-square test and discrete wavelet transform (DWT have been used for anomaly-based detection. The false data injection attack (FDIA can be detected using measurement residual. If the measurement residual is larger than expected detection threshold, then an alarm is triggered and bad data can be identified. Avoiding such alarms in the residual test is referred to as stealth attack. There are two protection strategies for stealth attack: (1 Select a subset of meters to be protected from the attacker (2 Place secure phasor measurement units in the power grid. An IEEE 14-bus system is simulated using real time digital simulator (RTDS hardware platform for implementing attack and detection schemes.

  10. A development of digital plant protection system architecture

    International Nuclear Information System (INIS)

    The digital plant protection system (DPPS) which have a large number of advantages compared to current analog protection system has been developed in various field. The major disadvantages of digital system are, however, vulnerable to faults of processor and software. To overcome the disadvantages, the concept of segment and partition in a channel has been developed. Each segment in a channel is divided from sensor to reactor trip and engineered safety features, which is based on the functional diversity of input signals against the various plant transient phenomena. Each partition allocates the function module to an independent processing module in order to process and isolate the faults of each module of a segment. A communication system based on the deterministic protocol with the predictable and hard real-time characteristics has been developed in order to link the various modules within a segment. The self-diagnostics including online test and periodic test procedures are developed in order to increase the safety, reliability and availability of DPPS. The developed DPPS uses the off-the-shelf DSP (digital signal processor) and adopts VME bus architecture, which have sufficient operation experience in the industry. The verification and validation and quality assurance of software has been developed and the architecture and protocol of deterministic communication system has been researched

  11. Qualification issues for advanced light-water reactor protection systems

    International Nuclear Information System (INIS)

    The instrumentation and control (I ampersand C) systems in advanced reactors will make extensive use of digital controls, microprocessors, multiplexing, and fiber optic transmission. Elements of these advances in I ampersand C have been implemented on some current operating plants. However, the widespread use of the above technologies, as well as the use of artificial intelligence with minimum reliance on human operator control of reactors, highlights the need to develop standards for qualifying the I ampersand C used in the next generation of nuclear power plants. As a first step in this direction, the protection system I ampersand C for present-day plants was compared to that proposed for advanced light-water reactors (ALWRs). An evaluation template was developed by assembling a configuration of a safety channel instrument string for a generic ALWR, then comparing the impact of environmental stressors on that string to their effect on an equivalent instrument string from an existing light-water reactor. The template was then used to suggest a methodology for the qualification of microprocessor-based protection systems. The methodology identifies standards/regulatory guides (or lack thereof) for the qualification of microprocessor-based safety I ampersand C systems. This approach addresses in part issues raised in NRC policy document SECY-91-292, which recognizes that advanced I ampersand C systems for the nuclear industry are ''being developed without consensus standards. as the technology available for design is ahead of the technology that is well understood through experience and supported by application standards.''

  12. Research on effectiveness assessment programs for physical protection system

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Janghoon; Yoo, Hosik; Ham, Taekyu [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2015-05-15

    PPS (Physical Protection System) is an integrated set of procedures, installation and human resources to protect valuable assets from physical attack of potential adversaries. Since nuclear facilities or radioactive materials can be attractive targets for terrorists, PPS should be installed and maintained throughout the entire lifecycle of nuclear energy systems. One of key ingredients for effective protection is a reliable assessment procedure of the PPS capability. Due to complexity of possible threat categories and pathways, several pathway analysis programs have been developed to ease analysis or visualization. ASSESS using ASD approach runs fast and adopts a relatively simple modeling process for facility elements. But uncertainty due to assumptions used in modeling might complicate the interpretation of results. On the other hand, 2D pathway program such as TESS can utilize more self-consistent detection probability and delay time since actual pathway on 2D map is available. Also, this pathway visualization helps users understand analysis result more intuitively. But, in general, 2D pathway programs require strong computational power and careful optimization. Another possible difference between two approaches is response force deployment and RFT.

  13. Protecting your files on the DFS file system

    CERN Multimedia

    Computer Security Team

    2011-01-01

    The Windows Distributed File System (DFS) hosts user directories for all NICE users plus many more data.    Files can be accessed from anywhere, via a dedicated web portal (http://cern.ch/dfs). Due to the ease of access to DFS with in CERN it is of utmost importance to properly protect access to sensitive data. As the use of DFS access control mechanisms is not obvious to all users, passwords, certificates or sensitive files might get exposed. At least this happened in past to the Andrews File System (AFS) - the Linux equivalent to DFS) - and led to bad publicity due to a journalist accessing supposedly "private" AFS folders (SonntagsZeitung 2009/11/08). This problem does not only affect the individual user but also has a bad impact on CERN's reputation when it comes to IT security. Therefore, all departments and LHC experiments agreed recently to apply more stringent protections to all DFS user folders. The goal of this data protection policy is to assist users in pro...

  14. MMOD Protection and Degradation Effects for Thermal Control Systems

    Science.gov (United States)

    Christiansen, Eric

    2014-01-01

    Micrometeoroid and orbital debris (MMOD) environment overview Hypervelocity impact effects & MMOD shielding MMOD risk assessment process Requirements & protection techniques - ISS - Shuttle - Orion/Commercial Crew Vehicles MMOD effects on spacecraft systems & improving MMOD protection - Radiators Coatings - Thermal protection system (TPS) for atmospheric entry vehicles Coatings - Windows - Solar arrays - Solar array masts - EVA Handrails - Thermal Blankets Orbital Debris provided by JSC & is the predominate threat in low Earth orbit - ORDEM 3.0 is latest model (released December 2013) - http://orbitaldebris.jsc.nasa.gov/ - Man-made objects in orbit about Earth impacting up to 16 km/s average 9-10 km/s for ISS orbit - High-density debris (steel) is major issue Meteoroid model provided by MSFC - MEM-R2 is latest release - http://www.nasa.gov/offices/meo/home/index.html - Natural particles in orbit about sun Mg-silicates, Ni-Fe, others - Meteoroid environment (MEM): 11-72 km/s Average 22-23 km/s.

  15. Study on vital area identification for physical protection system

    International Nuclear Information System (INIS)

    Physical protection (PP), which is required for the security of nuclear facilities and has recently caught the attention of the international community, is a mandatory design requirement for innovative nuclear energy systems. The International Atomic Energy Agency (IAEA) to this end has recommended its member countries to implement stronger physical protection measures when it amended the previous publication and released INFCIRC/225/Rev.5 in 2011; the core of the recommendation was the identification of vital areas (VAs). As the Korea Atomic Energy Research Institute (KAERI) has been developing an SFR fuel cycle with pyro processing as part of its nuclear energy R and D since the late 1990s, the concept of VAs should be incorporated at the process development and design stage in order to minimize later changes in facility design and prevent subsequent economic loss. This paper discusses the definition and process to identify VAs for the purpose of establishing physical protection systems (PPSs) for the relevant facilities in the future

  16. Evaluation of road-transit physical protection systems

    International Nuclear Information System (INIS)

    To assess the overall effectiveness of a transportation physical protection system, computer codes which simulate armed attacks have been developed and are being used to examine a range of issues associated with road transportation systems. The paper discusses the purpose and features of three of these codes, SOURCE (which simulates the initial ambush), SABRES I (which covers the battle) and BARS (which treats the penetration of protective cargo barriers). The use of these methodologies to evaluate the value of additional vehicles, guards, armor and alternative tactics or equipment as a means of improving convoy security has recently been completed. The results which are presented demonstrate that the protection offered by the present commercial regulations for guards and vehicles is probably marginal. This could be substantially increased by the addition of armor to close escort vehicles instead of just the transporter and the use of appropriate tactics. Against the baseline threat of adversaries armed with M-16's, observation and harassment from a modest distance until re-enforcements arrive appears preferable to aggressive assault by the ambushed guard force

  17. Protecting your files on the AFS file system

    CERN Multimedia

    2011-01-01

    The Andrew File System is a world-wide distributed file system linking hundreds of universities and organizations, including CERN. Files can be accessed from anywhere, via dedicated AFS client programs or via web interfaces that export the file contents on the web. Due to the ease of access to AFS it is of utmost importance to properly protect access to sensitive data in AFS. As the use of AFS access control mechanisms is not obvious to all users, passwords, private SSH keys or certificates have been exposed in the past. In one specific instance, this also led to bad publicity due to a journalist accessing supposedly "private" AFS folders (SonntagsZeitung 2009/11/08). This problem does not only affect the individual user but also has a bad impact on CERN's reputation when it comes to IT security. Therefore, all departments and LHC experiments agreed in April 2010 to apply more stringent folder protections to all AFS user folders. The goal of this data protection policy is to assist users in...

  18. An equipment protection and safety system for the ASDEX tokamak

    International Nuclear Information System (INIS)

    Our compromise between safety requirements and costs is a hybrid of relay, solid-state and computer-controlled protection systems used for ASDEX. The toroidal field coils, ohmic heating coils, vertical field coils, divertor coils, radial field coils, stainless-steel vacuum vessel and structure are protected by measuring the water flow (131 channels), temperature (142 channels), mechanical displacements (141 channels), voltage symmetry (28 channels), current symmetry (6 channels), weight of the vessel (8 channels) and the overvoltage. To detect flow, temperature, displacement, voltage, current and weight, we use the following devices: Venturi tubes (self-made), RTD thermoresistors (Pt-100), linear potentiometers (1 kΩ), voltage dividers (self-made), Rogowski coils (self-made) and straing gauges. (orig.)

  19. Field testing of the Advanced Worker Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Todd, R.J.E.; Hamill, D.

    1996-12-31

    AWPS is a life support system that allows a suited worker in operate in a chemically hazardous or radiologically hot environment for up to 2 hours with minimal heat stress and minimal encumbrance from his life support equipment. It consists of 3 parts: a backpack using liquid air to supply breathing gas and cooling power; a liquid cooling garment (LCG) that circulates water chilled from vaporizing and warming the cryogen; and a Level B protective garment which accommodates the low profile of the backpack, permits greater mobility and doesn`t require tape closure. The AWPS backpack and LCG are compatible with commercially available Level A protective garments. A one-hour demonstration of a AWPS prototype was done.

  20. New probabilistic decision-making tools for fire protection systems

    International Nuclear Information System (INIS)

    The FIVE methodology provides guidance to utilities in performing an examination of potential plant severe accidents caused by fire initiated events. FIVE is oriented toward uncovering limiting plant design or operating characteristics (vulnerabilities) that make certain fire-initiated events more likely than others. It provides a combination of deterministic and probabilistic techniques for examining a power plant's fire probability and protection characteristics. It includes a two phase progressive screening method and a third phase consisting of a plant walkdown/verification process. The FIVE methodology centers on providing assurance of the availability of at least one train of the safe shutdown systems. FIVE has been developed for implementation by plant personnel who are most experienced with their plant's operations, fire hazards and fire protection features. The methodology provides these plant personnel with guidelines to quickly screen the plant down to the most significant locations where vulnerabilities may exist and then identify options to reduce the vulnerabilities

  1. Reliability assessment of CEFR protection and safety monitoring system

    International Nuclear Information System (INIS)

    Nuclear safety is always the focus of public concern. At present, probabilistic safety assessment is one of the standard methods to assess the safety of nuclear power plants. It is also necessary to use probabilistic method to do the reliability analysis of each system of the nuclear power plant. China Experimental Fast Reactor (CEFR) is the first pool type sodium cooling fast breeder reactor in China. It is significant to carry through its probabilistic safety assessment and reliability analysis. In this paper, the fault trees of CEFR protection and safety monitoring system are constructed. The unavailability, importance, sensitivity and uncertainty are calculated. The common cause failures of the components in the typical positions are assessed. The analysis results indicate that the distribution of system minimal cut sets is well-proportioned. The design of this system is balanced, and do not have obvious weakness. The requirements of reactor shutdown during abnormal events are satisfied. (authors)

  2. Virtual-reality education and training system for radiation protection

    International Nuclear Information System (INIS)

    In order to break the mannerism in the education and training method for radiation protection introduction of virtual reality system to the chalkface has been discussed in addition to the usual lecture and video system in the subcommittee established in JRIAS (Japan Radioisotope Association), and the leading model has been installed in Osaka University. It consists of a main server and 3 clients with a software for virtual reality. With this system the trainee could go into the virtual laboratory and handle the radioisotope. In that case he could also experience various accidents such as trivial failure in the experiments, serious hazard, fire, earthquake, etc., which are difficult to suffer in the real laboratory. Hence those who have experienced such a training could come to act rapidly up against any sudden accidents and also the virtual reality system would result decrease in unnecessary radioactive wastes

  3. Thermal Protection System Imagery Inspection Management System -TIIMS

    Science.gov (United States)

    Goza, Sharon; Melendrez, David L.; Henningan, Marsha; LaBasse, Daniel; Smith, Daniel J.

    2011-01-01

    TIIMS is used during the inspection phases of every mission to provide quick visual feedback, detailed inspection data, and determination to the mission management team. This system consists of a visual Web page interface, an SQL database, and a graphical image generator. These combine to allow a user to ascertain quickly the status of the inspection process, and current determination of any problem zones. The TIIMS system allows inspection engineers to enter their determinations into a database and to link pertinent images and video to those database entries. The database then assigns criteria to each zone and tile, and via query, sends the information to a graphical image generation program. Using the official TIPS database tile positions and sizes, the graphical image generation program creates images of the current status of the orbiter, coloring zones, and tiles based on a predefined key code. These images are then displayed on a Web page using customized JAVA scripts to display the appropriate zone of the orbiter based on the location of the user's cursor. The close-up graphic and database entry for that particular zone can then be seen by selecting the zone. This page contains links into the database to access the images used by the inspection engineer when they make the determination entered into the database. Status for the inspection zones changes as determinations are refined and shown by the appropriate color code.

  4. Reactor protection system design using application specific integrated circuits

    International Nuclear Information System (INIS)

    Implementing reactor protection systems (RPS) or other engineering safeguard systems with application specific integrated circuits (ASICs) offers significant advantages over conventional analog or software based RPSs. Conventional analog RPSs suffer from setpoints drifts and large numbers of discrete analog electronics, hardware logic, and relays which reduce reliability because of the large number of potential failures of components or interconnections. To resolve problems associated with conventional discrete RPSs and proposed software based RPS systems, a hybrid analog and digital RPS system implemented with custom ASICs is proposed. The actual design of the ASIC RPS resembles a software based RPS but the programmable software portion of each channel is implemented in a fixed digital logic design including any input variable computations. Set point drifts are zero as in proposed software systems, but the verification and validation of the computations is made easier since the computational logic an be exhaustively tested. The functionality is assured fixed because there can be no future changes to the ASIC without redesign and fabrication. Subtle error conditions caused by out of order evaluation or time dependent evaluation of system variables against protection criteria are eliminated by implementing all evaluation computations in parallel for simultaneous results. On- chip redundancy within each RPS channel and continuous self-testing of all channels provided enhanced assurance that a particular channel is available and faults are identified as soon as possible for corrective actions. The use of highly integrated ASICs to implement channel electronics rather than the use of discrete electronics greatly reduces the total number of components and interconnections in the RPS to further increase system reliability. A prototype ASIC RPS channel design and the design environment used for ASIC RPS systems design is discussed

  5. Nuclear whistleblower protection system in U.S. and its implication to Japanese regulatory system

    International Nuclear Information System (INIS)

    The nuclear whistleblower protection system in U.S.A consists of two programs: 1) allegation program and 2) whistleblower protection system. The former is explained by basic act, definition of allegation, anonymous allegation, direct allegation to NRC (Nuclear Regulatory Commission), number of allegation from 1997 to 2001, procedure and period of investigation and notice of allegation to licensees. The latter is explained by basis act, outline of the system, enforcement by NRC and DOL (Department of Labor), number of discrimination compliant and anxiety of licensees. The system is good conditions in U.S.A depend on 1) prevent of illegal act and increase, 2) preparation of procedure and its transparency and 3) enforcement system. However, a hostile act to licensees is found in the whistleblower protection system. There are many problems in Japanese regulatory system. The improvement points of Japanese system are proposed. (S.Y.)

  6. Detection of fastener failure in a thermal protection system

    Science.gov (United States)

    Derriso, Mark M.; Olson, Steven E.; Braisted, William R.; DeSimio, Martin P.; Rosenstengel, John; Brown, Kevin

    2004-07-01

    This paper presents experimental and analytical studies focused on the development of a structural health monitoring system to assess the condition of mechanical fasteners of a thermal protection system. A realistic thermal protection system component, consisting of a carbon-carbon panel bolted through 15 brackets to a backing structure, is utilized. Mechanical states considered include all bolts fastened to a nominal torque value, or one of the 15 bolts loosened. Four transducers on the backing structure provide actuation and sensing signals. Spectral functions are computed from all single and pair-wise signal combinations. Automated analysis of the spectral functions shows frequency intervals exist over which the function values are indicative of the mechanical state of the test article. These frequency intervals are used to provide features for the structural health monitoring classifier. Finite element analyses provide a physics-based understanding of these features. Statistical pattern recognition methods select a subset of the features. The overall localization accuracy of the structural health monitoring system on test data is 99.1% with 99.7% probability of detecting a damaged condition at a 0.2% probability of a false alarm.

  7. Failsafe design criteria for computer based reactor protection systems

    International Nuclear Information System (INIS)

    The design criteria proposed are an extrapolation of the failsafe mode of operation used in the UK in hardwired reactor protection systems. This is achieved by making the operational condition of the reactor dependent upon an energetic state of the protection system components. An important objective of the proposed design criteria is to eliminate, or at least to minimize, the need for a failure-mode-and-effect-analysis (FMEA) of the computer software. This demands some well defined but simple constraints upon the way in which data are stored in the computers, but the objective is achieved almost entirely by hardware properties of the system. The first of these is the systematic use of hardwired test inputs which cause transient excursions into the tripped state in a uniquely ordered but easily recognizable sequence. The second is the use of hardwired pattern recognition logic which generates a dynamic healthy stimulus for the shutdown actuators only in response to the unique sequence formed by the hardwired input signal pattern. It therefore detects abnormal states of any of the system inputs, software errors, wiring errors and hardware failures. This hardwired logic is conceptually simple, failsafe, and is amenable to simple FMEA. (U.K.)

  8. Cathode-follower power amplifier

    International Nuclear Information System (INIS)

    In circular accelerators and particularly in storage rings it is essential that the total impedance, as seen by the beam, be kept below some critical value. A model of the accelerating system was built using a single-ended cathode-follower amplifier driving a ferrite-loaded cavity. The system operated at 234.5 kHz with a peak output voltage of +-10 kV on the gap. The dynamic output impedance, as measured on the gap, was < 15 ohms

  9. [The revised system of hospitalization for medical care and protection].

    Science.gov (United States)

    Fukuo, Yasuhisa

    2014-01-01

    The Act to Partially Amend the Act on Mental Health and Welfare for the Mentally Disabled was passed on June 13, 2013. Major amendments regarding hospitalization for medical care and protection include the points listed below. The guardianship system will be abolished. Consent by a guardian will no longer be required in the case of hospitalization for medical care and protection. In the case of hospitalization for medical care and protection, the administrators of the psychiatric hospital are required to obtain the consent of one of the following persons: spouse, person with parental authority, person responsible for support, legal custodian, or curator. If no qualified person is available, consent must be obtained from the mayor, etc. of the municipality. The following three obligations are imposed on psychiatric hospital administrators. (1) Assignment of a person, such as a psychiatric social worker, to provide guidance and counseling to patients hospitalized for medical care and protection regarding their postdischarge living environment. (2) Collaboration with community support entities that consult with and provide information as necessary to the person hospitalized, their spouse, a person with parental authority, a person responsible for support, or their legal custodian or curator. (3) Organizational improvements to promote hospital discharge. With regard to requests for discharge, the revised law stipulates that, in addition to the person hospitalized with a mental disorder, others who may file a request for discharge with the psychiatric review board include: the person's spouse, a person with parental authority, a person responsible for support, or their legal custodian or curator. If none of the above persons are available, or if none of them are able to express their wishes, the mayor, etc. of the municipality having jurisdiction over the place of residence of the person hospitalized may request a discharge. In order to promote transition to life in the

  10. Scanning optical pyrometer for measuring temperatures in hollow cathodes

    International Nuclear Information System (INIS)

    Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed

  11. Experimental Investigation of Thruster Cathode Physics

    Science.gov (United States)

    Crofton, Mark

    2004-11-01

    Advanced ion propulsion technologies are being developed under the Nuclear Electric Xenon Ion System (NEXIS) program for use in outer planet exploration. A revolutionary approach to thruster cathode design is dictated by the very high lifetime and propellant throughput requirements for nuclear electric applications. In conventional dispenser hollow cathodes used in thrusters, processes leading to depletion, inadequate transport, or insufficient production of barium are among those limiting the lifetime. A reservoir hollow cathode is being developed to address each of these failure mechanisms, exploiting four design variables - matrix material, source material, geometry, and thermal design - to essentially eliminate established failure modes. The very long anticipated lifetime necessitates new life validation methods to augment or replace the conventional lifetest approach. One important tool for quickly evaluating design changes is the ability to measure barium density inside a hollow cathode and/or in the plume. The dependence of barium density on temperature and other factors is an extremely important indicator of cathode health, particularly if the ratio Ba:BaO is also obtained. Comparison of barium production for reservoir and conventional cathodes will enable an assessment of the efficacy of reservoir designs and the goal of reducing barium consumption at a given emission current level. This study describes benchmark measurements made on a conventional cathode previously operated in a 20-kW NEXIS laboratory engine. Data on cathode operation and life-limiting processes were obtained through direct, real-time monitoring of atoms and molecules. A high-resolution, tunable laser system was employed to detect absorption of the low-density barium atoms inside the cathode. The plume was monitored also, using a quadrupole mass spectrometer to monitor multiple species and measure ion charge ratios. Data obtained with retarding potential analyzers or other means are

  12. Strengthening physical protection of nuclear material. National systems versus multinational systems

    International Nuclear Information System (INIS)

    The paper gives a brief history of the development of multinational systems on the physical protection of nuclear material, the roles of national physical protection systems and multinational systems, political and social changes in the post-Cold-War era and their implications on the physical protection activities, as well as recommendations. In the early 1970s there were many terrorist attacks including airline hijacking world wide. Subsequently, the nuclear community was seriously concerned about the possible risks of unauthorized removal of nuclear material by sub-national groups, threatening to produce and use crud nuclear explosive devices. The IAEA published the guidelines on the physical protection of nuclear material during use, storage and transport (INFCIRC/225) in 1975. The multinational nuclear export control regime (the Nuclear Suppliers' Guidelines) incorporate the requirement of physical protection measures (1978), and the Convention on the Physical Protection of Nuclear Material entered into force in 1987. The responsibility for physical protection of nuclear material in individual States rest with the State. The purpose of multinational systems is basically, to formulate and recommend internationally accepted guidelines, etc. Also a State can be requested to ensure maintenance of the responsibilities from international treaties, etc. National systems and multinational systems are interdependent, and changes to national systems will lead to eventual changes to multinational systems and vice versa. In the post-Cold-War era, there have been many political and social changes. The most significant political, security and social changes are: diversification of the risks of nuclear proliferation, illicit trafficking of nuclear material, and weakening of the power of 'nation States'. In view of this, the worldwide physical protection activities should be strengthened, especially those of multinational systems. In the last section of the paper, seven

  13. Defense against common-mode failures in protection system design

    International Nuclear Information System (INIS)

    The introduction of digital instrumentation and control into reactor safety systems creates a heightened concern about common-mode failure. This paper discusses the concern and methods to cope with the concern. Common-mode failures have been a ''fact-of-life'' in existing systems. The informal introduction of defense-in-depth and diversity (D-in-D ampersand D)-coupled with the fact that hardware common-mode failures are often distributed in time-has allowed systems to deal with past common-mode failures. However, identical software operating in identical redundant systems presents the potential for simultaneous failure. Consequently, the use of digital systems raises the concern about common-mode failure to a new level. A more methodical approach to mitigating common-mode failure is needed to address these concerns. Purposeful introduction of D-in-D ampersand D has been used as a defense against common-mode failure in reactor protection systems. At least two diverse systems are provided to mitigate any potential initiating event. Additionally, diverse displays and controls are provided to allow the operator to monitor plant status and manually initiate engineered safety features. A special form of conimon-mode failure analysis called ''defense-in-depth and diversity analysis'' has been developed to identify possible conimon-mode failure vulnerabilities in digital systems. An overview of this analysis technique is provided

  14. Large area dispenser cathode applied to high current linac

    International Nuclear Information System (INIS)

    The paper introduced a dispenser cathode (411 M) which was 55 mm in diameter. A 200 kV long pulsed power generator with 2 μs flattop based on Marx-PEN and system with heat and voltage insulation were built. A 52 A space charge limited current was gained, when the temperature was 1165 degree C and the filament current was 18 A on the cathode and the voltage of the pulse was 75 kV at the cathode test stand. Experimental results show that the current values are consistent with the numerical simulation. The experiment reveals that the deflated gas will influence the cathode emission ability. (authors)

  15. NSTX Protection And Interlock Systems For Coil And Powers Supply Systems

    International Nuclear Information System (INIS)

    NSTX at Princeton Plasma Physics Laboratory (PPPL) requires sophisticated plasma positioning control system for stable plasma operation. TF magnetic coils and PF magnetic coils provide electromagnetic fields to position and shape the plasma vertically and horizontally respectively. NSTX utilizes twenty six coil power supplies to establish and initiate electromagnetic fields through the coil system for plasma control. A power protection and interlock system is utilized to detect power system faults and protect the TF coils and PF coils against excessive electromechanical forces, overheating, and over current. Upon detecting any fault condition the power system is restricted, and it is either prevented from initializing or suppressed to de-energize coil power during pulsing. Power fault status is immediately reported to the computer system. This paper describes the design and operation of NSTX's protection and interlocking system and possible future expansion.

  16. Thermal Protection Materials Technology for NASA's Exploration Systems Mission Directorate

    Science.gov (United States)

    Valentine, Peter G.; Lawerence, Timtohy W.; Gubert, Michael K.; Flynn, Kevin C.; Milos, Frank S.; Kiser, James D.; Ohlhorst, Craig W.; Koenig, John R.

    2005-01-01

    To fulfill the President s Vision for Space Exploration - successful human and robotic missions between the Earth and other solar system bodies in order to explore their atmospheres and surfaces - NASA must reduce trip time, cost, and vehicle weight so that payload and scientific experiment capabilities are maximized. As a collaboration among NASA Centers, this project will generate products that will enable greater fidelity in mission/vehicle design trade studies, support risk reduction for material selections, assist in optimization of vehicle weights, and provide the material and process templates for development of human-rated qualification and certification Thermal Protection System (TPS) plans. Missions performing aerocapture, aerobraking, or direct aeroentry rely on technologies that reduce vehicle weight by minimizing the need for propellant. These missions use the destination planet s atmosphere to slow the spacecraft. Such mission profiles induce heating environments on the spacecraft that demand thermal protection heatshields. This program offers NASA essential advanced thermal management technologies needed to develop new lightweight nonmetallic TPS materials for critical thermal protection heatshields for future spacecraft. Discussion of this new program (a December 2004 new start) will include both initial progress made and a presentation of the work to be preformed over the four-year life of the program. Additionally, the relevant missions and environments expected for Exploration Systems vehicles will be presented, along with discussion of the candidate materials to be considered and of the types of testing to be performed (material property tests, space environmental effects tests, and Earth and Mars gases arc jet tests).

  17. Thermal Protection System Aerothermal Screening Tests in HYMETS Facility

    Science.gov (United States)

    Szalai, Christine E.; Beck, Robin A. S.; Gasch, Matthew J.; Alumni, Antonella I.; Chavez-Garcia, Jose F.; Splinter, Scott C.; Gragg, Jeffrey G.; Brewer, Amy

    2011-01-01

    The Entry, Descent, and Landing (EDL) Technology Development Project has been tasked to develop Thermal Protection System (TPS) materials for insertion into future Mars Entry Systems. A screening arc jet test of seven rigid ablative TPS material candidates was performed in the Hypersonic Materials Environmental Test System (HYMETS) facility at NASA Langley Research Center, in both an air and carbon dioxide test environment. Recession, mass loss, surface temperature, and backface thermal response were measured for each test specimen. All material candidates survived the Mars aerocapture relevant heating condition, and some materials showed a clear increase in recession rate in the carbon dioxide test environment. These test results supported subsequent down-selection of the most promising material candidates for further development.

  18. Nuclear power protection systems performance study for APR 1400

    International Nuclear Information System (INIS)

    A study on plant protection system (PPS) of advanced power reactor (APR) 1400 which is one of the system to maintain nuclear power plant (NPP) operation safe and controllable has been conducted. The controllability aspect of NPP operation is an important aspect to assure the NPP operation safe and reliable. Accordingly, the study is limited in the performance of PPS. The method used in the study includes literature study, data collection, as well as review and analysis. The purpose of this study is to recognize that PPS performance can assure the NPP operation safely and controllable. The study concludes that there are several measurement parameters that actuate PPS systems to trip the reactor such as high pressurizer pressure, low pressurizer pressure, high containment building pressure and also manual trip. These parameters are measured by parallel sensor with parallel arrangement set on set point suitable with APR 1400 safety standard. (author)

  19. Protection of Distribution Systems with Distributed Energy Resources

    DEFF Research Database (Denmark)

    Bak-Jensen, Birgitte; Browne, Matthew; Calone, Roberto;

    practice may lead to a loss of significant generation where each feeder may have significant DER penetration. Also, utilities have started to investigate islanding operation of distribution systems with DER as a way to improve the reliability of the power supply to customers. This report is the result of...... that include DER (chapter 5). It features the impact of DER on distribution system protection and sums up recommended best practices for reliable island detection. The third main part offers a proactive approach to technology trends (chapter 6), under consideration of new applications of teleprotection......The usage of Distributed Energy Resources (DER) in utilities around the world is expected to increase significantly. The existing distribution systems have been generally designed for unidirectional power flow, and feeders are opened and locked out for any fault within. However, in the future this...

  20. Terahertz Computed Tomography of NASA Thermal Protection System Materials

    Science.gov (United States)

    Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

    2011-01-01

    A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

  1. District heating systems between competition protection and climate protection; Die Fernwaermenetze zwischen Wettbewerbs- und Klimaschutz

    Energy Technology Data Exchange (ETDEWEB)

    Koerber, Torsten [Goettingen Univ. (Germany). Lehrstuhl fuer Buergerliches Recht, Kartellrecht, Versicherungs-, Gesellschafts- und Regulierungsrecht

    2012-10-15

    In principle, district heating systems come in the application area of paragraph 19 sect. 4 no. 4 GWB (law against competitive restrictions). However, this regulation has to be interpreted with respect to the legislation of the Court of Justice of the European Union (Luxemburg) to 'essential facilities'. According to this, the claim for antitrust access can be affirmed only in exceptional circumstances. Within the application of this regulation, property rights, competition protection, investment competition, innovation competition as well as energy political evaluations of the energy law under special consideration of ecologic and climate political targets are considered. This has to occur within the testing of the reasonability with respect to paragraph 19 sect. 4 no. 2 GWB. The particularities of the district heating.

  2. BIODIVERSITY AND THE PROTECTED AREAS SYSTEM IN ALBANIA

    Directory of Open Access Journals (Sweden)

    Mehmet Metaj

    2009-06-01

    Full Text Available Albania possesses a wide range of ecological systems including coastal zones, estuaries and lagoons, lakes and wetlands, grasslands, middle-low altitude coppice forests, high altitude forests, alpine vegetation and glacial areas. The country possesses about 3,250 species of vascular plants, 165 families and more than 900 genera. Medicinal plants (botanicals and non-timber forest products have a long history of importance in the culture and traditional knowledge of Albania. Proper legislation and especially legal and regulatory framework enforcement for the regulation of this developing industry remains lacking. A Strategy of Biodiversity plan developed in 2000 calls for an increase in the Protected Areas system which currently covers some 6 % of Albania's area to a total area of 435,600 ha, approximately 15 % of the country's territory. Changes in the legal and policy framework as well as institutional structures is required to move forward and provide an environment for biodiversity conservation and a sustainable protected areas system. The various threats to biodiversity and constraints to improvement are outlined as well as recommendations for sustainable use, assessment and regulation.

  3. Equipment design for reliability testing of protection system

    International Nuclear Information System (INIS)

    The equipment for reliability testing of cable of protection system has been designed as a a furnace with the electric heater have a 4 kW power, and need time 10 minute to reach the designed maximum temperature 3000C. The dimension of furnace is 800 mm diameter and 2000 mm length is isolated use rockwool isolator and coated by aluminium. For the designed maximum temperature the surface temperature is 78 0c. Assemble of specimens is arranged horizontally in the furnace. The failure criteria will be defined based on the behaviour of the load circuit in each line of cable specimens

  4. Information support systems for cultural heritage protection against flood

    Czech Academy of Sciences Publication Activity Database

    Nedvědová, Klára; Pergl, R.

    Vol. XL-5/W7. Göttingen: Copernicus Publications, 2015 - (Yen, Y.; Weng, K.; Cheng, H.), s. 343-346 ISSN 2194-9034. [International CIPA Symposium /25./. Taipei (TW), 31.08.2015-04.09.2015] R&D Projects: GA MK(CZ) DF11P01OVV009 Keywords : cultural heritage * flooding * information support systems * flood protection planning * vulnerability assessment * open-source software * process modeling Subject RIV: AL - Art, Architecture, Cultural Heritage http://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XL-5-W7/343/2015/isprsarchives-XL-5-W7-343-2015.html

  5. Protecting clinical data in PACS, teleradiology systems, and research environments

    Science.gov (United States)

    Meissner, Marion C.; Collmann, Jeff R.; Tohme, Walid G.; Mun, Seong K.

    1997-05-01

    As clinical data is more widely stored in electronic patient record management systems and transmitted over the Internet and telephone lines, it becomes more accessible and therefore more useful, but also more vulnerable. Computer systems such as PACS, telemedicine applications, and medical research networks must protect against accidental or deliberate modification, disclosure, and violation of patient confidentiality in order to be viable. Conventional wisdom in the medical field and among lawmakers legislating the use of electronic medical records suggests that, although it may improve access to information, an electronic medical record cannot be as secure as a traditional paper record. This is not the case. Information security is a well-developed field in the computer and communications industry. If medical information systems, such as PACS, telemedicine applications, and research networks, properly apply information security techniques, they can ensure the accuracy and confidentiality of their patient information and even improve the security of their data over a traditional paper record. This paper will elaborate on some of these techniques and discuss how they can be applied to medical information systems. The following systems will be used as examples for the analysis: a research laboratory at Georgetown University Medical Center, the Deployable Radiology system installed to support the US Army's peace- keeping operation in Bosnia, a kidney dialysis telemedicine system in Washington, D.C., and various experiences with implementing and integrating PACS.

  6. Highly Efficient Micro Cathode Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek Company, Inc. proposes to develop a micro thermionic cathode that requires extremely low power and provides long lifetime. The basis for the cathode is a...

  7. Advanced Cathode Electrolyzer (ACE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a static, cathode-fed, 2000 psi, balanced-pressure Advanced Cathode Electrolyzer (ACE) based on PEM electrolysis technology. It...

  8. Fault Rid Through Protection of DFIG Based Wind Generation System

    Directory of Open Access Journals (Sweden)

    S. Sajedi

    2012-03-01

    Full Text Available This study proposes a fault ride-through strategy for a Doubly Fed Induction Generator (DFIG to enhance network stability during grid disturbances. To enable efficient computation a reduced order DFIG model is developed that restricts the calculation to the fundamental frequency component. However, the model enhancement introduced in the paper allows the consideration of the alternating components of the rotor current as well which is necessary for triggering the crowbar operation. As protection against short circuit transients, the crowbar protection is employed in the simulation. An equivalent model is constructed. Simplifications are made so as to have a system composed of grid, transformer, line and generator represented by elementary circuit elements (R, L, C and voltage sources. Equivalent circuit models are simplified so that the fault models may be used for synchronous machine parameters. It is assumed that the mechanical system cannot respond during the short time of a three phase short circuit. Simulation results in MATLABSimulink software are presented for model verification purposes.

  9. Experimental study on a transpiration cooling thermal protection system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Transpiration cooling thermal protection systems (TPS) are investigated for potential applications in hypersonic and re-entry vehicles,which are subjected to the severe aerodynamic heating environment. In this paper a transpiration cooling thermal protection system was designed and manufactured,and an experiment platform with radiant heating at the bottom as heat source was developed. The cooling capacity of the transpiration cooling TPS was experimentally investigated. By combining transpiration cooling method with traditional TPS,the heat load capability of the TPS can be improved. The structure temperature with active cooling applied was much lower than that without active cooling applied under the same heat load as well as the heat load increased with active cooling than the one without active cooling for the same structure temperature. The experimental results showed that at 5800 s,the temperature of inner structure was 100°C with active cooling applied compared to 500°C without active cooling applied,then the temperature increased and reached to 360°C at 8300 s. Heat load of this transpiration cooling TPS can be increased by over 70% as compared to the passion one and the cooling capability of the transpiration TPS was about 1700 kJ/kg. The results can provide fundamental data for developing the transpiration cooling TPS.

  10. Intercropping System for Protection the Potato Plant from Insect Infestation

    Directory of Open Access Journals (Sweden)

    Aziza Sharaby

    2015-06-01

    Full Text Available The use of intercropping system provides an option for insect control for organic farmers that are limited in their chemical use. Additionally, intercropping systems can be attractive to conventional growers as a cost-effective insect control solution. A study was carried out for two seasons 2011-2012 and 2012-2013 to evaluate the effect of intercropping of potato (Solanum tuberosum L. with onion (Allium cepa L. on whitefly (Bemicia tabasi Gennadius and aphids’ Myzus persicae Sulz. and Aphis gossypii Glover infestation in potato fields. Results indicated that intercropping significantly reduced potato plant infestation with whitefly by 42.7, 51.3% while it was 62.69% reduction with aphids during the two successive winter seasons than when potato plants were cultivated alone. Therefore, intercropping could be recommended as a protection method of reducing pest population in the fields.

  11. Degradation and Failure Characteristics of NPP Containment Protective Coating Systems

    International Nuclear Information System (INIS)

    Nuclear power plants (NPPs) must ensure that the emergency core cooling system (ECCS) or safety-related containment spray system (CSS) remains capable of performing its design safety function throughout the life of the plant. This requires ensuring that long-term core cooling can be maintained following a postulated loss-of-coolant accident (LOCA). Adequate safety operation can be impaired if the protective coatings which have been applied to the concrete and steel structures within the primary containment fail, producing transportable debris which could then accumulate on BWR ECCS suction strainers or PWR ECCS sump debris screens located within the containment. This document will present the data collected during the investigation of coating specimens from plants

  12. Wecpos - Wave Energy Coastal Protection Oscillating System: A Numerical Assessment

    Science.gov (United States)

    Dentale, Fabio; Pugliese Carratelli, Eugenio; Rzzo, Gianfranco; Arsie, Ivan; Davide Russo, Salvatore

    2010-05-01

    In recent years, the interest in developing new technologies to produce energy with low environmental impact by using renewable sources has grown exponentially all over the world. In this context, the experiences made to derive electricity from the sea (currents, waves, etc.) are of particular interest. At the moment, due to the many existing experiments completed or still in progress, it is quite impossible explain what has been obtained but it is worth mentioning the EMEC, which summarizes the major projects in the world. Another important environmental aspect, also related to the maritime field, is the coastal protection from the sea waves. Even in this field, since many years, the structural and non-structural solutions which can counteract this phenomenon are analyzed, in order to cause the least possible damage to the environment. The studies in development by the researchers of the University of Salerno are based on these two aspect previously presented. Considering the technologies currently available, a submerged system has been designed, WECPOS (Wave Energy Coastal Protection Oscillating System), to be located on relatively shallow depths, to can be used simultaneously for both electricity generation and for the coastal protection using the oscillating motion of the water particles. The single element constituting the system is realized by a fixed base and three movable panels that can fluctuate in a fixed angle. The waves interact with the panels generating an alternative motion which can be exploited to produce electricity. At the same time, the constraint movement imposed for the rotation of the panels is a barrier to the wave propagation phenomena, triggering the breaking in the downstream part of the device. So the wave energy will be dissipated obtaining a positive effect for the coastal protection. Currently, the efficiency and effectiveness of the system (WECPOS single module) has been studied by using numerical models. Using the FLOW-3D

  13. A New Protection System for Islanding Detection in LV Distribution Systems

    Directory of Open Access Journals (Sweden)

    Anna Rita Di Fazio

    2015-04-01

    Full Text Available The growth of penetration of Distributed Generators (DGs is increasing the risk of unwanted islanded operation in Low Voltage (LV distribution systems. In this scenario, the existing anti-islanding protection systems, installed at the DG premises and based on classical voltage and frequency relays, are no longer effective, especially in the cases of islands characterized by a close match between generation and load. In this paper, a new protection system for islanding detection in LV distribution systems is proposed. The classical voltage and frequency relays in the DG interface protections are enriched with an innovative Smart Islanding Detector, which adopts a new passive islanding detection method. The aim is to keep the advantages of the classical relays while overcoming the problem of their limited sensitivity in detecting balanced islands. In the paper, to define the requirements of the anti-islanding protection system, the events causing the islanded operation of the LV distribution systems are firstly identified and classified. Then, referring to proposed protection system, its architecture and operation are described and, eventually, its performance is analyzed and validated by experimental laboratory tests, carried out with a hardware-in-the-loop technique.

  14. Cathode material for lithium batteries

    Science.gov (United States)

    Park, Sang-Ho; Amine, Khalil

    2013-07-23

    A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

  15. Compact Rare Earth Emitter Hollow Cathode

    Science.gov (United States)

    Watkins, Ronald; Goebel, Dan; Hofer, Richard

    2010-01-01

    A compact, high-current, hollow cathode utilizing a lanthanum hexaboride (LaB6) thermionic electron emitter has been developed for use with high-power Hall thrusters and ion thrusters. LaB6 cathodes are being investigated due to their long life, high current capabilities, and less stringent xenon purity and handling requirements compared to conventional barium oxide (BaO) dispenser cathodes. The new cathode features a much smaller diameter than previously developed versions that permit it to be mounted on axis of a Hall thruster ( internally mounted ), as opposed to the conventional side-mount position external to the outer magnetic circuit ("externally mounted"). The cathode has also been reconfigured to be capable of surviving vibrational loads during launch and is designed to solve the significant heater and materials compatibility problems associated with the use of this emitter material. This has been accomplished in a compact design with the capability of high-emission current (10 to 60 A). The compact, high-current design has a keeper diameter that allows the cathode to be mounted on the centerline of a 6- kW Hall thruster, inside the iron core of the inner electromagnetic coil. Although designed for electric propulsion thrusters in spacecraft station- keeping, orbit transfer, and interplanetary applications, the LaB6 cathodes are applicable to the plasma processing industry in applications such as optical coatings and semiconductor processing where reactive gases are used. Where current electrical propulsion thrusters with BaO emitters have limited life and need extremely clean propellant feed systems at a significant cost, these LaB6 cathodes can run on the crudest-grade xenon propellant available without impact. Moreover, in a laboratory environment, LaB6 cathodes reduce testing costs because they do not require extended conditioning periods under hard vacuum. Alternative rare earth emitters, such as cerium hexaboride (CeB6) can be used in this

  16. 78 FR 30870 - Nomination of Existing Marine Protected Areas to the National System of Marine Protected Areas

    Science.gov (United States)

    2013-05-23

    ... November 19, 2008 (73 FR 69608). The Framework provides guidance for collaborative efforts among federal... National Oceanic and Atmospheric Administration Nomination of Existing Marine Protected Areas to the... sites to the National System of MPAs (national system). The national system and the nomination...

  17. Measures for the explosion protection for gas systems; Massnahmen des Explosionsschutzes fuer Gasanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Faber, Wolfgang [Thyssengas GmbH, Duisburg (Germany). Anlagentechnik Nord; Seemann, Albert [BG ETEM Berufsgenossenschaft Energie Textil Elektro Medienerzeugnisse, Koeln (Germany)

    2012-04-15

    In order to protect employees, technical and organizational measures for explosion protection have to be provided to gas plants with potentially explosive areas. These measures have to be documented in the explosion protection document in accordance with paragraph 6 section 1 of the regulation of industrial safety. The contribution under consideration presents an overview on the measures for explosion protection for gas systems.

  18. Protection of Hardware: Powering Systems (Power Converter, Normal Conducting, and Superconducting Magnets)

    CERN Document Server

    Pfeffer, H; Wolff, D

    2016-01-01

    Along with the protection of magnets and power converters, we have added a section on personnel protection because this is our highest priority in the design and operation of power systems. Thus, our topics are the protection of people, power converters, and magnet loads (protected from the powering equipment), including normal conducting magnets and superconducting magnets.

  19. Production of conductive coke for cathodic protection

    Energy Technology Data Exchange (ETDEWEB)

    Mogollon, E.G.; Henao, L.E.; Pacheco, L.A.; Ortiz, J.L.; Diaz, J.J. [Universidad Nacional de Colombia, Bogota (Colombia). Departamento de Quimica

    1999-07-01

    The reduction of resistivity of coke by means of the cocarbonization of mixtures of coking coals was studied using coal tar as an additive. Optimum temperature and blending conditions for decreased resistivity were investigated. The effect of particle size on the dependency of coal rank was investigated. 2 refs., 4 figs., 2 tabs.

  20. A New GPS-based Digital Protection System for Smart Grids in Loop Structure

    Directory of Open Access Journals (Sweden)

    X. Liu

    2014-12-01

    Full Text Available This paper presents a new digital protection system to solve the protection challenges in future smart grids, i.e., fast protection and fault isolation in a loop-structured system with limited magnitude of fault current. The new system combines two protection algorithms, i.e., a differential protection as the primary algorithm and an overcurrent protection as the backup one. The new system uses real-time Ethernet and digital data acquisition techniques to overcome the restriction on data transmission over large grids. The current measurements at different locations are time-synchronized by GPS clocks, and then transmitted to a central computer via the Ethernet. As opposed to digital relays which often contain PMU functionality nowadays, this approach uses time stamps on the instantaneous current values. We build a prototype of the new system on a test-bed. The results from simulations and experiments have demonstrated that the protection system achieves fast and accurate protection.

  1. The evolution of the system of radiological protection: the programme of the Nea committee on radiation protection and public health

    International Nuclear Information System (INIS)

    The primary aim of radiological protection has always been to provide an appropriate standard of protection for the public and workers without unduly limiting the beneficial practices giving rise to radiation exposure. Over the past few decades, many studies concerning the effects of ionising radiation have been conducted, ranging from those that examine the effects of radiation on individual cells, to epidemiological studies that examine the effects on large populations exposed to different radiation sources. Using information gained from these studies to estimate the consequences of radiation exposure, together with the necessary social and economic judgements, the International Commission on Radiological Protection (ICRP) has put forward a series of recommendations to structure an appropriate system for radiological protection, and to ensure a high standard of protection for the public and for occupational exposed workers. The ICRP system of radiological protection that has evolved over the years now covers many diverse radiological protection issues. Emerging issues have been dealt with more or less on an individual basis resulting in an overall system, which while very comprehensive, is also complex. With such a complex system it is not surprising that some perceived inconsistencies or incoherence may lead to concerns that radiation protection issues are not being adequately addressed. Different stakeholders in decisions involving radiological protection aspects tend to focus on different elements of this perceived incoherence. To advance solutions to these issues, the OECD Nuclear Energy Agency (NEA) has been working for some time to contribute to the evolution of a new radiological protection system, through its Committee on Radiation Protection and Public Health (CRPPH). This group of senior regulators and expert practitioners has, throughout its existence, been interested in the development of recommendations by the ICRP. Recently, this interest has

  2. Trivial risks and the new radiation protection system

    International Nuclear Information System (INIS)

    The International Commission on Radiological Protection proposes that doses below a certain level should be excluded from the system of protection, without regard to the number of people exposed. As the Commission assumes that there is a risk of harm even from very low doses, the proposal also disregards these very low risks. The arguments for this proposal are examined here. It is argued that the fact that risks are small compared to natural sources cannot be used as justification for accepting them. The principle 'if the risk of harm to the health of the most exposed individual is trivial, then the total risk is trivial-irrespective of how many people are exposed' is analysed. It is found to equivocate on the meaning of the word trivial and to ignore the total risk. It is also argued that the new proposal is not justified by a change from a utilitarian ethic to an ethic based on individual rights. Finally, it is suggested that small doses should only be disregarded if the expected value of harm is small, and the exclusion level should thus depend on the number of people exposed

  3. System 80+trademark standard design incorporates radiation protection lessons learned

    International Nuclear Information System (INIS)

    Many lessons have been learned from the current generation of nuclear plants in the area of radiation protection. The following paper will outline how the lessons learned have been incorporated into the design and operational philosophy of the System 80+trademark Standard Design currently under development by ABB Combustion Engineering (ABB-CE) with support from Duke Engineering and Services, Inc. and Stone and Webster Engineering Corporation in the Balance-of-Plant design. The System 80+trademark Standard Design is a complete nuclear power plant for national and international markets, designed in direct response to utility needs for the 1990's, and scheduled for Nuclear Regulatory Commission (NRC) Design Certification under the new standardization rule (10 CFR Part 52). System 80+trademark is a natural extension of System 80R technology, an evolutionary change based on proven Nuclear Steam Supply System (NSSS) in operation at Palo Verde in Arizona and under construction at Yonggwang in the Republic of Korea. The System 80+trademark Containment and much of the Balance of Plant design is based upon Duke Power Company's Cherokee Plant, which was partially constructed in the late 1970's, but, was later canceled (due to rapid declined in electrical load growth). The System 80+trademark Standard Design meets the requirements given in the Electric Power Research Institute (EPRI) Advanced Light Water Reactor (ALWR) Requirements Document. One of these requirements is to limit the occupational exposure to 100 person-rem/yr. This paper illustrates how this goal can be achieved through the incorporation of lessons learned, innovative design, and the implementation of a common sense approach to operation and maintenances practices

  4. Symmetry-protected topological phases in noninteracting fermion systems

    Science.gov (United States)

    Wen, Xiao-Gang

    2012-02-01

    Symmetry-protected topological (SPT) phases are gapped quantum phases with a certain symmetry, which can all be smoothly connected to the same trivial product state if we break the symmetry. For noninteracting fermion systems with time reversal (T̂), charge conjugation (Ĉ), and/or U(1) (N̂) symmetries, the total symmetry group can depend on the relations between those symmetry operations, such as T̂N̂T̂-1=N̂ or T̂N̂T̂-1=-N̂. As a result, the SPT phases of those fermion systems with different symmetry groups have different classifications. In this paper, we use Kitaev's K-theory approach to classify the gapped free-fermion phases for those possible symmetry groups. In particular, we can view the U(1) as a spin rotation. We find that superconductors with the Sz spin-rotation symmetry are classified by Z in even dimensions, while superconductors with the time reversal plus the Sz spin-rotation symmetries are classified by Z in odd dimensions. We show that all 10 classes of gapped free-fermion phases can be realized by electron systems with certain symmetries. We also point out that, to properly describe the symmetry of a fermionic system, we need to specify its full symmetry group that includes the fermion number parity transformation (-)N̂. The full symmetry group is actually a projective symmetry group.

  5. Programming Guidelines for FBD Programs in Reactor Protection System Software

    International Nuclear Information System (INIS)

    Properties of programming languages, such as reliability, traceability, etc., play important roles in software development to improve safety. Several researches are proposed guidelines about programming to increase the dependability of software which is developed for safety critical systems. Misra-c is a widely accepted programming guidelines for the C language especially in the sector of vehicle industry. NUREG/CR-6463 helps engineers in nuclear industry develop software in nuclear power plant systems more dependably. FBD (Function Block Diagram), which is one of programming languages defined in IEC 61131-3 standard, is often used for software development of PLC (programmable logic controllers) in nuclear power plants. Software development for critical systems using FBD needs strict guidelines, because FBD is a general language and has easily mistakable elements. There are researches about guidelines for IEC 61131-3 programming languages. They, however, do not specify details about how to use languages. This paper proposes new guidelines for the FBD based on NUREG/CR-6463. The paper introduces a CASE (Computer-Aided Software Engineering) tool to check FBD programs with the new guidelines and shows availability with a case study using a FBD program in a reactor protection system. The paper is organized as follows

  6. Model-based design of protected cultivation system - first results and remaining challenges

    OpenAIRE

    Henten, van, J.W.; Vanthoor, B.H.E.; Stanghellini, C.; Visser, de, P.H.B.; Hemming, S.

    2012-01-01

    Abstract: Protected cultivation systems are used throughout the world as a powerful instrument to produce crops. They protect the crops from unfavorable outdoor climate conditions and pests and offer the opportunity to modify the indoor climate to create an environment that is optimal for crop growth and production, both in terms of quality and quantity. A quick scan of protected cultivation systems presently in use reveals that quite a variety of protected cultivation systems can be found th...

  7. Design and implementation based on the classification protection vulnerability scanning system

    International Nuclear Information System (INIS)

    With the application and spread of the classification protection, Network Security Vulnerability Scanning should consider the efficiency and the function expansion. It proposes a kind of a system vulnerability from classification protection, and elaborates the design and implementation of a vulnerability scanning system based on vulnerability classification plug-in technology and oriented classification protection. According to the experiment, the application of classification protection has good adaptability and salability with the system, and it also approves the efficiency of scanning. (authors)

  8. Graded Density Carbon Bonded Carbon Fiber (CBCF) Preforms for Lightweight Ablative Thermal Protection Systems (TPS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FMI currently manufactures Phenolic Impregnated Carbon Ablator (PICA) material for Thermal Protection Systems (TPS) systems, such as the Stardust Sample Return...

  9. Evaluating physical protection systems of licensed nuclear facilities using systems engineered inspection guidance

    International Nuclear Information System (INIS)

    The Lawrence Livermore National Laboratory (LLNL) and the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research (RES) have applied a systems engineering approach to provide the NRC Office of Inspection and Enforcement (IE) with improved methods and guidance for evaluating the physical protection systems of licensed nuclear facilities

  10. Robotic system for the servicing of the orbiter thermal protection system

    Science.gov (United States)

    Graham, Todd; Bennett, Richard; Dowling, Kevin; Manouchehri, Davoud; Cooper, Eric; Cowan, Cregg

    1994-01-01

    This paper describes the design and development of a mobile robotic system to process orbiter thermal protection system (TPS) tiles. This work was justified by a TPS automation study which identified tile rewaterproofing and visual inspection as excellent applications for robotic automation.

  11. Photoassisted electrochemical recirculation system with boron-doped diamond anode and carbon nanotubes containing cathode for degradation of a model azo dye

    International Nuclear Information System (INIS)

    In this research work, a photoassisted electrochemical system under recirculation mode and with UV irradiation was designed for treatment of C.I. Acid Blue 92 (AB92) as a model anionic azo dye in aqueous solution. Degradation experiments were carried out with boron-doped diamond (BDD) anode and carbon nanotubes-polytetrafluoroethylene (CNTs-PTFE) cathode in the presence of sulfate as an electrolyte. A comparative study of AB92 degradation by photolysis, electrochemical oxidation and photoassisted electrochemical processes after 45 min of treatment demonstrated that degradation efficiency was 27.89, 37.65 and 95.86%, respectively. Experimental data revealed that the degradation rate of AB92 in all of the processes obeyed pseudo-first-order kinetics and application of photoassisted electrochemical system reduced electrical energy per order (EEO), considerably. Degradation efficiency of photoassisted electrochemical process enhanced by increasing applied current and flow rate values, but vice versa trend was observed for initial dye concentration and an optimum amount of 6 was obtained for initial pH. The TOC measurement results demonstrated that 93.24% of organic substrates were mineralized after 120 min of photoassisted electrochemical process and GC–Mass analysis was performed for identification of degradation intermediates

  12. Application of DCS for protection system in nuclear power plant

    International Nuclear Information System (INIS)

    The safety DCS based on digital technology has replaced analog technology to become mainstream applications for protection systems in the nuclear power plant. The reliability of DCS technology is very important because high safety requirements for nuclear power plants. In order to ensure the reliability of the DCS technology design, by analyzed the requirements of relevant codes and standards, summed up the qualification test items and software verification and validation process shall be performed for safety DCS design, and combining technical characteristics of the current major several safety DCS application product. The key technologies points of controller, intelligent IO module, priority actuation module and communication etc. should be considered for the safety DCS design and development are proposed. (author)

  13. A detailed study of patent system for protection of inventions.

    Science.gov (United States)

    Tulasi, G Krishna; Rao, B Subba

    2008-09-01

    Creations of brain are called intellect. Since these creations have good commercial value, are called as property. Inventions are intellectual property and can be protected by patents provided the invention is novel, non-obvious, useful and enabled. To have fare trade among member countries, World Trade Organisation proposed TRIPS agreement. India had taken necessary initiation by signing the World Trade Organisation agreement and transformed to global needs. The aim of this article is to enlighten pharmaceutical professionals especially in the field of research and development about planning inventions by thorough review of prior-art, which saves time and money. A thorough understanding is made possible by providing details of origin; present governing bodies, their role along with the Act that is safeguarding the patent system. PMID:21394248

  14. A detailed study of patent system for protection of inventions

    Directory of Open Access Journals (Sweden)

    Tulasi G

    2008-01-01

    Full Text Available Creations of brain are called intellect. Since these creations have good commercial value, are called as property. Inventions are intellectual property and can be protected by patents provided the invention is novel, non-obvious, useful and enabled. To have fare trade among member countries, World Trade Organisation proposed TRIPS agreement. India had taken necessary initiation by signing the World Trade Organisation agreement and transformed to global needs. The aim of this article is to enlighten pharmaceutical professionals especially in the field of research and development about planning inventions by thorough review of prior-art, which saves time and money. A thorough understanding is made possible by providing details of origin; present governing bodies, their role along with the Act that is safeguarding the patent system.

  15. Ballistic Performance of Porous-Ceramic, Thermal-Protection-Systems

    Science.gov (United States)

    Christiansen, E. L.; Davis, B. A.; Miller, J. E.; Bohl, W. E.; Foreman, C. D.

    2009-01-01

    Porous-ceramic, thermal protection systems are used heavily in current reentry vehicles like the Space Shuttle and are currently being proposed for the next generation of manned spacecraft, Orion. These materials insulate the structural components of a spacecraft against the intense thermal environments of atmospheric reentry. Furthermore, these materials are also highly exposed to space environmental hazards like meteoroid and orbital debris impacts. This paper discusses recent impact testing up to 9 km/s, and the findings of the influence of material equation-of-state on the simulation of the impact event to characterize the ballistic performance of these materials. These results will be compared with heritage models1 for these materials developed from testing at lower velocities. Assessments of predicted spacecraft risk based upon these tests and simulations will also be discussed.

  16. Software technique research for digital reactor protection system

    International Nuclear Information System (INIS)

    The rapid development of modern information technology makes the application of computer to nuclear Reactor Protection System (RPS) becomes an irreversible trend, thus brings about a digital nuclear RPS. A digital RPS can achieve higher reliability, accuracy and stability than an analog one, while dramatically improving the RPS functions. Safe software is one of key techniques of digital RPS. The digitalization of RPS also brings some new technical issues, such as software reliability and software verification and validation (V and V). Based on Chinese existing regulations, guides, standards and criteria, and the IAEA and the European and American developed countries' relevant technical documentations, some investigations on how to improve the quality of RPS software and how to ensure the safety and reliability of RPS software were made. The results have some theoretical and engineering significance for China's digital RPS research, especially for the digital RPS implementation of China's own designed High Temperature Gas-cooled Reactor (HTGR) demonstration project. (authors)

  17. Topologically protected modes in non-equilibrium stochastic systems

    CERN Document Server

    Murugan, Arvind

    2016-01-01

    Non-equilibrium driving of biochemical reactions is believed to enable their robust functioning despite the presence of thermal fluctuations and other sources of disorder. Such robust functions include sensory adaptation, enhanced enyzmatic specificity and maintenance of coherent oscillations. Non-equilibrium biochemical reactions can be modeled as a master equation whose rate constants break detailed balance. We find that non equilibrium fluxes can support topologically protected boundary modes that resemble similar modes in electronic and mechanical systems. We show that when a biochemical network can be decomposed into two ordered bulks that meet at a possibly disordered interferace, the ordered bulks can be each associated with a topologically invariant winding number. If the winding numbers are mismatched, we are guaranteed that the steady state distribution is localized at the interface between the bulks, even in the presence of strong disorder in reaction rates. We argue that our work provides a framew...

  18. Verification station for Sandia/Rockwell Plutonium Protection system

    International Nuclear Information System (INIS)

    A verification station has been designed to confirm the presence of plutonium within a container module. These container modules [about 13 cm (5 in.) in diameter and 23 cm (9 in.) high] hold sealed food-pack cans containing either plutonium oxide or metal and were designed by Sandia Laboratories to provide security and continuous surveillance and safety. After the plutonium is placed in the container module, it is closed with a solder seal. The verification station discussed here is used to confirm the presence of plutonium in the container module before it is placed in a carousel-type storage array inside the plutonium storage vault. This measurement represents the only technique that uses nuclear detectors in the plutonium protection system

  19. Key issues concerning changes in the radiological protection system: some thoughts from the French Society for Radiation Protection (SFRP)

    International Nuclear Information System (INIS)

    In 1999, the International Radiological Protection Association (IRPA) asked for contributions to the debate on future changes to the radiological protection system proposed by the International Commission on Radiological Protection (ICRP). In response, the Board of the French Society for Radiation Protection (SFRP) created a working group to deal specifically with this issue. It met on several occasions between April and July and its findings were presented at the IRPA Congress in May 2000. They were also published in the French journal Radioprotection and in the British Journal of Radiological Protection. To further its discussions, the Board of the SFRP decided to create a second working group which became operational in September 2001. It has around 20 members representing the major players in the radiological protection field in France: authorities, experts and professionals from the nuclear, medical and research fields as well as one association representative (the list of members can be found at the end of this document). The working group was set up to produce proposals relating to the key issues likely to be raised, particularly by the ICRP, concerning the development of new radiological protection recommendations. The members of the working group analysed the ICRP memorandum published in the June 2001 edition of the Journal of Radiological Protection and used their own experience to determine what these key issues would be. The following issues were discussed: General thoughts on the new radiological protection system proposed by the ICRP, Individual and collective approaches to the radiological risk, Comparison with chemical risk management, Radiological protection of the environment, Changes in exposure levels and units of measurement. This paper, which has been approved by the Board of the SFRP, gives the main conclusions of the working group on the key issues in these areas. It is intended to reflect the various opinions expressed during the groups

  20. Insights from a reliability review of digital plant protection system

    International Nuclear Information System (INIS)

    The full text follows: As part of the design efforts for Ulchin nuclear power plant units 5 and 6 of Korea, a reliability analysis of digital plant protection system (DPPS) was performed by ABB-CE. An independent review of the DPPS reliability analysis was undertaken by Hanyang University to assist Korea Institute of Nuclear Safety (KINS), the nuclear regulatory body of Korea, in evaluating the design acceptability of the digital system. The DPPS is designed to encompass both reactor trip function and ESFAS (engineered safety feature actuation system) initiation function. The major methods used by the ABB-CE to assess the Ulchin 5-6 DPPS reliability are failure mode and effect analysis (FMEA) and fault tree analysis. Hence, our independent review was conducted focusing on: -) the establishment of review criteria based on various sources, such as the standard review plan of KINS, 10CFR50 Appendix A, IEEE standards 279, 577, and 603; -) the suitability of the FMEA and fault tree analysis for the Ulchin 5-6 DPPS, including the specific methods used (e.g., for human reliability analysis and common-cause failure analysis), the assumptions made (e.g., with respect to test frequency and watchdog timer coverage), and the data employed (e.g., CCF parameter, human error probability, and processor failure rate); and -) the design acceptability of the DPPS especially as compared to the analog plant protection system from a reliability and safety perspective. The paper shall also discuss key issues requiring further in-depth investigation, such as reliability of programmable logic controllers (PLCs), coverage factor of watchdog timers, and susceptibility of redundant digital units to common cause failure. Sensitivity analyses were carried out to investigate the impact of several parameters of special interest, like the coverage factor of watchdog timer and human error probability (e.g. an operator error to manually trip the reactor, or to mis-calibrate the trip parameters) on