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Sample records for control rod applications

  1. Control rod testing apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Gaunt, R.R.; Ashman, C.M.

    1987-06-02

    A control rod testing apparatus is described comprising: a first guide means having a vertical cylindrical opening for grossly guiding a control rod; a second guide means having a vertical cylindrical opening for grossly guiding a control rod. The first and second guide means are supported at axially spaced locations with the openings coaxial; and a substantially cylindrical subassembly having a vertical cylindrical opening therethrough. The subassembly is trapped coaxial with and between the first and second guide means, and the subassembly radially floats with respect to the first and second guide means.

  2. REACTOR CONTROL ROD OPERATING SYSTEM

    Science.gov (United States)

    Miller, G.

    1961-12-12

    A nuclear reactor control rod mechanism is designed which mechanically moves the control rods into and out of the core under normal conditions but rapidly forces the control rods into the core by catapultic action in the event of an emergency. (AEC)

  3. Advanced gray rod control assembly

    Science.gov (United States)

    Drudy, Keith J; Carlson, William R; Conner, Michael E; Goldenfield, Mark; Hone, Michael J; Long, Jr., Carroll J; Parkinson, Jerod; Pomirleanu, Radu O

    2013-09-17

    An advanced gray rod control assembly (GRCA) for a nuclear reactor. The GRCA provides controlled insertion of gray rod assemblies into the reactor, thereby controlling the rate of power produced by the reactor and providing reactivity control at full power. Each gray rod assembly includes an elongated tubular member, a primary neutron-absorber disposed within the tubular member said neutron-absorber comprising an absorber material, preferably tungsten, having a 2200 m/s neutron absorption microscopic capture cross-section of from 10 to 30 barns. An internal support tube can be positioned between the primary absorber and the tubular member as a secondary absorber to enhance neutron absorption, absorber depletion, assembly weight, and assembly heat transfer characteristics.

  4. Control rods in LMFBRs: a physics assessment

    Energy Technology Data Exchange (ETDEWEB)

    McFarlane, H.F.; Collins, P.J.

    1982-08-01

    This physics assessment is based on roughly 300 control rod worth measurements in ZPPR from 1972 to 1981. All ZPPR assemblies simulated mixed-oxide LMFBRs, representing sizes of 350, 700, and 900 MWe. Control rod worth measurements included single rods, various combinations of rods, and Ta and Eu rods. Additional measurements studied variations in B/sub 4/C enrichment, rod interaction effects, variations in rod geometry, neutron streaming in sodium-filled channels, and axial worth profiles. Analyses were done with design-equivalent methods, using ENDF/B Version IV data. Some computations for the sensitivities to approximations in the methods have been included. Comparisons of these analyses with the experiments have allowed the status of control rod physics in the US to be clearly defined.

  5. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, Gareth; Ahn, Jae-Hwan; Kim, Nack-Joon

    1986-01-01

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar.sub.3 temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics.

  6. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, G.; Ahn, J.H.; Kim, N.J.

    1986-10-28

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar[sub 3] temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics. 3 figs.

  7. Control Rod Malfunction at the NRAD Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L. Maddock

    2010-05-01

    The neutron Radiography Reactor (NRAD) is a training, research, and isotope (TRIGA) reactor located at the INL. The reactor is normally shut down by the insertion of three control rods that drop into the core when power is removed from electromagnets. During a routine shutdown, indicator lights on the console showed that one of the control rods was not inserted. It was initially thought that the indicator lights were in error because of a limit switch that was out of adjustment. Through further testing, it was determined that the control rod did not drop when the scram switch was initially pressed. The control rod anomaly led to a six month shutdown of the reactor and an in depth investigation of the reactor protective system. The investigation looked into: scram switch operation, console modifications, and control rod drive mechanisms. A number of latent issues were discovered and corrected during the investigation. The cause of the control rod malfunction was found to be a buildup of corrosion in the control rod drive mechanism. The investigation resulted in modifications to equipment, changes to both operation and maintenance procedures, and additional training. No reoccurrences of the problem have been observed since corrective actions were implemented.

  8. Magnetically controlled growing rods for scoliosis surgery.

    Science.gov (United States)

    Metkar, Umesh; Kurra, Swamy; Quinzi, David; Albanese, Stephen; Lavelle, William F

    2017-02-01

    Early onset scoliosis can be both a disfiguring as well as a life threatening condition. When more conservative treatments fail, pediatric spinal surgeons are forced to consider operative interventions. Traditionally, these interventions have involved the insertion of a variety of implants into the patient with a limited number of anchor points controlling the spine. In the past, these pediatric patients have had multiple surgeries for elective lengthening of these devices to facilitate their growth while attempting to control the scoliosis. These patients often experience a physical and emotional toll from their multiple repeated surgeries. Growing spine techniques have also had a noted high complication rate due to implant dislodgement and infections. Recently, the development of non-invasively, self-lengthening growing rods has occurred. These devices have the potential to allow for the devices to be lengthened magnetically in a conscious patient in the surgeon's office. Areas covered: This review summarized previously published articles in the English literature using a key word search in PubMed for: 'magnetically controlled growing rods', 'Magec rods', 'magnetic growing rods' and 'growing rods'. Expert commentary: Magnetically controlled growing rods have an advantage over growing rods in lengthening the growing spine in the absence of repetitive surgeries.

  9. Application of B{sub 4}C/Al{sub 2}O{sub 3} Burnable Absorber Rod to Control Excess Reactivity of SMR

    Energy Technology Data Exchange (ETDEWEB)

    Muth, Boravy; Hah, C. J. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2016-10-15

    Soluble boron in a nuclear reactor coolant is one of the methods to control excess reactivity of the reactor. However, the use of soluble boron also causes some negative effects such as corrosion, more-positive tendency of Moderator Temperature Coefficient (MTC) and the requirement of Chemical Volume Control System (CVCS). One of the conceptual design features of SMR having been developed in Korea is soluble boron- free reactor to eliminate those drawbacks. Control rods and Burnable Absorber (BA) rods can be other methods than soluble to control excess reactivity. WABA (Wet Annular Burnable Absorber) and PYREX are such type. The other type is IFBA (Integral Fuel Burnable Absorber) in which fuel pellet surface is coated with BA. This paper compares nuclear characteristics of three types of BA as well as SLOBA in terms of k-infinite vs. burnup and explain design basis of SLOBA. This paper also presents the application of SLOBA rods to control long-term excess reactivity of SMR. The SMR loaded with SLOBA rods has been developed for the past few years in Korean. It is named as Bandi-50 with design features of 180 MWth, 37 FAs, fuel assembly height of 200 cm. Soluble-boron-free is one of nuclear design requirements of Bandi-50 and is achieved by controlling excess reactivity of the SMR using BAs and control rods only. To achieve this design requirement, LP is carefully determined in such way that CBC should be as low as possible. Fuel assembly cross-sections are generated by CASMO-3, and core depletion calculations are performed by MASTER.

  10. Estimation of irradiated control rod worth

    Energy Technology Data Exchange (ETDEWEB)

    Varvayanni, M., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Antonopoulos-Domis, M. [School of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki (Greece)

    2009-11-15

    When depleted control rods are planned to be used in new core configurations, their worth has to be accurately predicted in order to deduce key design and safety parameters such as the available shutdown margin. In this work a methodology is suggested for the derivation of the distributed absorbing capacity of a depleted rod, useful in the case that the level of detail that is known about the irradiation history of the control rod does not allow an accurate calculation of the absorber's burnup. The suggested methodology is based on measurements of the rod's worth carried out in the former core configuration and on corresponding calculations based on the original (before first irradiation) absorber concentration. The methodology is formulated for the general case of the multi-group theory; it is successfully tested for the one-group approximation, for a depleted control rod of the Greek Research Reactor, containing five neutron absorbers. The computations reproduce satisfactorily the irradiated rod worth measurements, practically eliminating the discrepancy of the total rod worth, compared to the computations based on the nominal absorber densities.

  11. Regulatory perspective on incomplete control rod insertions

    Energy Technology Data Exchange (ETDEWEB)

    Chatterton, M.

    1997-01-01

    The incomplete control rod insertions experienced at South Texas Unit 1 and Wolf Creek are of safety concern to the NRC staff because they represent potential precursors to loss of shutdown margin. Even before it was determined if these events were caused by the control rods or by the fuel there was an apparent correlation of the problem with high burnup fuel. It was determined that there was also a correlation between high burnup and high drag forces as well as with rod drop time histories and lack of rod recoil. The NRC staff initial actions were aimed at getting a perspective on the magnitude of the problem as far as the number of plants and the amount of fuel that could be involved, as well as the safety significance in terms of shutdown margin. As tests have been performed and data has been analyzed the focus has shifted more toward understanding the problem and the ways to eliminate it. At this time the staff`s understanding of the phenomena is that it was a combination of factors including burnup, power history and temperature. The problem appears to be very sensitive to these factors, the interaction of which is not clearly understood. The model developed by Westinghouse provides a possible explanation but there is not sufficient data to establish confidence levels and sensitivity studies involving the key parameters have not been done. While several fixes to the problem have been discussed, no definitive fixes have been proposed. Without complete understanding of the phenomena, or fixes that clearly eliminate the problem the safety concern remains. The safety significance depends on the amount of shutdown margin lost due to incomplete insertion of the control rods. Were the control rods to stick high in the core, the reactor could not be shutdown by the control rods and other means such as emergency boration would be required.

  12. Radiological characterization of spent control rod assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Lepel, E.A.; Robertson, D.E.; Thomas, C.W.; Pratt, S.L.; Haggard, D.L. [Pacific Northwest Lab., Richland, WA (United States)

    1995-10-01

    This document represents the final report of an ongoing study to provide radiological characterizations, classifications, and assessments in support of the decommissioning of nuclear power stations. This report describes the results of non-destructive and laboratory radionuclide measurements, as well as waste classification assessments, of BWR and PWR spent control rod assemblies. The radionuclide inventories of these spent control rods were determined by three separate methodologies, including (1) direct assay techniques, (2) calculational techniques, and (3) by sampling and laboratory radiochemical analyses. For the BWR control rod blade (CRB) and PWR burnable poison rod assembly (BPRA), {sup 60}Co and {sup 63}Ni, present in the stainless steel cladding, were the most abundant neutron activation products. The most abundant radionuclide in the PWR rod cluster control assembly (RCCA) was {sup 108m}Ag (130 yr halflife) produced in the Ag-In-Cd alloy used as the neutron poison. This radionuclide will be the dominant contributor to the gamma dose rate for many hundreds of years. The results of the direct assay methods agree very well ({+-}10%) with the sampling/radiochemical measurements. The results of the calculational methods agreed fairly well with the empirical measurements for the BPRA, but often varied by a factor of 5 to 10 for the CRB and the RCCA assemblies. If concentration averaging and encapsulation, as allowed by 10CFR61.55, is performed, then each of the entire control assemblies would be classified as Class C low-level radioactive waste.

  13. Friction measuring device for control rod

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Tomomi.

    1994-03-18

    In the present invention, judgment for friction of control rods conducted upon periodical inspection of a BWR type power plant is conducted by automatic analysis and evaluation by digitalizing data of an operation pressure and an differential pressure of control rods. That is, a differential pressure detection means detects a pressure and a differential pressure of driving water of a control rod driving source. A data processing device conducts digital analysis and store data from the differential pressure detection means, as well as compares the data with set values to automatically judge the friction of the control rod to diagnose abnormality based on the changing trend of the analyzed data. According to the device of the present invention, data measured for the friction of a great number of control rods can be analyzed and judged automatically in a short period of time. Accordingly, evaluation can be conducted accurately even by less skilled operators. Further, when an abnormality is detected, the diagnosis thereof is conducted, so that the operation is simplified and an operator's burden upon inspection can be mitigated. (I.S.).

  14. Sensitivity study of control rod depletion coefficients

    OpenAIRE

    Blomberg, Joel

    2015-01-01

    This report investigates the sensitivity of the control rod depletion coefficients, Sg, to different input parameters and how this affects the accumulated 10B depletion, β. Currently the coefficients are generated with PHOENIX4, but the geometries can be more accurately simulated in McScram. McScram is used to calculate Control Rod Worth, which in turn is used to calculate Nuclear End Of Life, and Sg cannot be generated in the current version of McScram. Therefore, it is also analyzed whether...

  15. Application of polyimide actuator rod seals

    Science.gov (United States)

    Watermann, A. W.; Gay, B. F.; Robinson, E. D.; Srinath, S. K.; Nelson, W. G.

    1972-01-01

    Development of polyimide two-stage hydraulic actuator rod seals for application in high-performance aircraft was accomplished. The significant portion of the effort was concentrated on optimization of the chevron and K-section second-stage seal geometries to satisfy the requirements for operation at 450 K (350 F) with dynamic pressure loads varying between 200 psig steady-state and 1500 psig impulse cycling. Particular significance was placed on reducing seal gland dimension by efficiently utilizing the fatigue allowables of polyimide materials. Other objectives included investigation of pressure balancing techniques for first-stage polyimide rod seals for 4000 psig 450 K(350 F) environment and fabrication of a modular retainer for the two-stage combination. Seals were fabricated in 0.0254 m (1.0in.) and 0.0635 m (2.5in.) sizes and tested for structural integrity, frictional resistance, and endurance life. Test results showed that carefully designed second stages using polyimides could be made to satisfy the dynamic return pressure requirements of applications in high-performance aircraft. High wear under full system pressure indicated that further research is necessary to obtain an acceptable first-stage design. The modular retainer was successfully tested and showed potential for new actuator applications.

  16. Dependence of control rod worth on fuel burnup

    Energy Technology Data Exchange (ETDEWEB)

    Savva, P., E-mail: savvapan@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Varvayanni, M., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N., E-mail: nicos@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece)

    2011-02-15

    Research highlights: Diffusion and MC calculations for rod worth dependence on burnup and Xe in reactors. One-step rod withdrawal/insertion are used for rod worth estimation. The study showed that when Xe is present the rods worth is significantly reduced. Rod worth variation with burnup depends on rod position in core. Rod worth obtained with MC code is higher than that obtained from deterministic. - Abstract: One important parameter in the design and the analysis of a nuclear reactor core is the reactivity worth of the control rods, i.e. their efficiency to absorb excess reactivity. The control rod worth is affected by parameters such as the fuel burnup in the rod vicinity, the Xe concentration in the core, the operational time of the rod and its position in the core. In the present work, two different computational approaches, a deterministic and a stochastic one, were used for the determination of the rods worth dependence on the fuel burnup level and the Xe concentration level in a conceptual, symmetric reactor core, based on the MTR fuel assemblies used in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system composed by the SCALE modules NITAWL and XSDRN and the diffusion code CITATION was used, while for the stochastic one the Monte Carlo code TRIPOLI was applied. The study showed that when Xe is present in the core, the rods worth is significantly reduced, while the rod worth variation with increasing burnup depends on the rods position in the core grid. The rod worth obtained with the use of the Monte Carlo code is higher than the one obtained from the deterministic code.

  17. Static in situ test of the axial power shaping rod and shim safety control rod mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Soberano, F T; Gannon, J A; Parlee, K A

    1982-08-01

    There are eight Axial Power Shaping Rods (APSRs) and 61 Shim Safety Control Rods (SSCRs) within the Three Mile Island (TMI) Unit 2 reactor core. This report describes the test results for all eight APSRs and three SSCRs. The tests were performed in situ from the Control Rod Drive (CRD) system logic cabinets and the transformer cabinets located in the cable spreading room. The tests were intended to determine the condition of the Absolute Position Indicators (APIs), the stator thermocouples, and the stators, and to assess each components' survival of the TMI-2 accident.

  18. Nuclear reactor shutdown control rod assembly

    Science.gov (United States)

    Bilibin, Konstantin

    1988-01-01

    A temperature responsive, self-actuated nuclear reactor shutdown control rod assembly 10. The upper end 18 of a lower drive line 17 fits within the lower end of an upper drive line 12. The lower end (not shown) of the lower drive line 17 is connected to a neutron absorber. During normal temperature conditions the lower drive line 17 is supported by detent means 22,26. When an overtemperature condition occurs thermal actuation means 34 urges ring 26 upwardly sufficiently to allow balls 22 to move radially outwardly thereby allowing lower drive line 17 to move downwardly toward the core of the nuclear reactor resulting in automatic reduction of the reactor powder.

  19. Optimized Control Rods of the BR2 Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kalcheva, Silva; Koonen, E.

    2007-09-15

    At the present time the BR-2 reactor uses control elements with cadmium as neutron absorbing part. The lower section of the control element is a beryllium assembly cooled by light water. Due to the burn up of the lower end of the cadmium section during the reactor operation, the presently used rods for reactivity control of the BR-2 reactor have to be replaced by new ones. Considered are various types Control Rods with full active part of the following materials: cadmium (Cd), hafnium (Hf), europium oxide (Eu2O3) and gadolinium (Gd2O3). Options to decrease the burn up of the control rod material in the hot spot, such as use of stainless steel in the lower active part of the Control Rod are discussed. Comparison with the characteristics of the presently used Control Rods types is performed. The changing of the characteristics of different types Control Rods and the perturbation effects on the reactor neutronics during the BR-2 fuel cycle are investigated. The burn up of the Control Rod absorbing material, total and differential control rods worth, macroscopic and effective microscopic absorption cross sections, fuel and reactivity evolution are evaluated during approximately 30 operating cycles.

  20. Power Maneuvering of Pressurized Water Reactors with Axially Variable Strength Control Rods

    Science.gov (United States)

    Kim, Ung-Soo; Seong, Poong-Hyun

    2004-02-01

    In this research, axially variable strength control rods (AVSCRs) are developed to solve the problems related to the axial power distribution of a reactor during power maneuvering of pressurized water reactors (PWRs). The control rods are classified into two types: multipurpose control rods and regulating control rods. Two multipurpose control rod banks (AVSCR1, AVSCR2) are newly developed; conventional axially uniform strength control rods are adopted as regulating control rod banks to minimize the design change. The newly developed AVSCRs are axially three-sectioned and their worth shapes are optimized to obtain appropriate moving characteristics related to the variation of the axial offset (AO) according to the motion of the AVSCRs. The operation strategy for the power maneuvering is developed in consideration of the moving characteristics of the AVSCRs. This strategy consists of simple logics, and no use of reactivity compensation by boron is considered. Finally, the AVSCRs are applied to the power maneuvering with a typical 100-50-100%, 2-6-2-14 h pattern of daily load-follow for all burn-up state of the core. From the application results, it is shown that the use of AVSCRs makes it possible to regulate AO within the target band during the power maneuvering with only control rods. Consequently, power maneuvering is accomplished without reactivity compensation by a change in boron concentration, and the AVSCRs can cover the entire burn-up states of the reactor core.

  1. RODMOD: a code for control rod positioning. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Vondy, D.R.; Fowler, T.B.

    1978-11-01

    The report documents a computer code which has been implemented to position control rods according to a prescribed schedule during the calculation of a reactor history. Control rods may be represented explicitly with or without internal black absorber conditions in selected energy groups, or fractional insertion may be done, or both, in a problem. There is provision for control rod follower, movement of materials through a series of zones in a closed loop, and shutdown rod insertion and subsequent removal to allow the reactor history calculation to be continued. This code is incorporated in the system containing the VENTURE diffusion theory neutronics and the BURNER exposure codes for routine use. The implemented automated procedures cause the prescribed control rod insertion schedule to be applied without the access of additional user input data during the calculation of a reactor operating history.

  2. Dynamic behavior of upper hydraulic drive control rod

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaotian [Institute of Nuclear and New Energy Technology, Beijing 100084 (China)]. E-mail: lixiaotian@tsinghua.edu.cn; He Shuyan [Institute of Nuclear and New Energy Technology, Beijing 100084 (China)

    2006-12-15

    A 200 MW nuclear heating reactor (NHR) was developed based on the 5 MW testing heating reactor (THR-5). In order to improve its features, the INET was used to optimize its structure design. One task was to design the upper hydraulic drive control rod, which is located at the upper part of the reactor core, so that the fuel rod in each corner of the bundle will not be removed as they are in the THR-5. A program based on the method of characteristics was run to investigate the dynamic behavior of the upper hydraulic control rod drive system. The steady-state and dynamic characteristics of the control rod were studied. The influence of the reactor temperature and structure parameters on the operation reliability was investigated. Finally the optimal design parameters of the upper hydraulic drive control rod were obtained.

  3. Rapid calibaration of the control rod of miniature neutron source ...

    African Journals Online (AJOL)

    An innovative method of combining the well-known computer codes WIMS and CITATION in an interactive Windows environment to calculate the control rod worth and generate the calibration data/curve of single-contr-ol rod miniature source reactor (MNSR) types has been developed and tested. In the scheme, once ...

  4. Review of FFTF and CRBRP control rod systems designs

    Energy Technology Data Exchange (ETDEWEB)

    Pitterle, T. A.; Lagally, H. O.

    1977-10-04

    The evolution of the primary control rod system design for FFTF and CRBR, beginning with the initial choice of the basic concepts, is described. The significant component and systems tests are reviewed together with the test results which referenced the development of the CRBR primary control rod system design. Modifications to the concepts and detail designs of the FFTF control rod system were required principally to satisfy the requirements of CRBR, and at the same time incorporating design refinements shown desirable by the tests.

  5. The development of a thermal hydraulic feedback mechanism with a quasi-fixed point iteration scheme for control rod position modeling for the TRIGSIMS-TH application

    Science.gov (United States)

    Karriem, Veronica V.

    Nuclear reactor design incorporates the study and application of nuclear physics, nuclear thermal hydraulic and nuclear safety. Theoretical models and numerical methods implemented in computer programs are utilized to analyze and design nuclear reactors. The focus of this PhD study's is the development of an advanced high-fidelity multi-physics code system to perform reactor core analysis for design and safety evaluations of research TRIGA-type reactors. The fuel management and design code system TRIGSIMS was further developed to fulfill the function of a reactor design and analysis code system for the Pennsylvania State Breazeale Reactor (PSBR). TRIGSIMS, which is currently in use at the PSBR, is a fuel management tool, which incorporates the depletion code ORIGEN-S (part of SCALE system) and the Monte Carlo neutronics solver MCNP. The diffusion theory code ADMARC-H is used within TRIGSIMS to accelerate the MCNP calculations. It manages the data and fuel isotopic content and stores it for future burnup calculations. The contribution of this work is the development of an improved version of TRIGSIMS, named TRIGSIMS-TH. TRIGSIMS-TH incorporates a thermal hydraulic module based on the advanced sub-channel code COBRA-TF (CTF). CTF provides the temperature feedback needed in the multi-physics calculations as well as the thermal hydraulics modeling capability of the reactor core. The temperature feedback model is using the CTF-provided local moderator and fuel temperatures for the cross-section modeling for ADMARC-H and MCNP calculations. To perform efficient critical control rod calculations, a methodology for applying a control rod position was implemented in TRIGSIMS-TH, making this code system a modeling and design tool for future core loadings. The new TRIGSIMS-TH is a computer program that interlinks various other functional reactor analysis tools. It consists of the MCNP5, ADMARC-H, ORIGEN-S, and CTF. CTF was coupled with both MCNP and ADMARC-H to provide the

  6. Control Rod Driveline Reactivity Feedback Model for Liquid Metal Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Young-Min; Jeong, Hae-Yong; Chang, Won-Pyo; Cho, Chung-Ho; Lee, Yong-Bum

    2008-01-15

    The thermal expansion of the control rod drivelines (CRDL) is one important passive mitigator under all unprotected accident conditions in the metal and oxide cores. When the CRDL are washed by hot sodium in the coolant outlet plenum, the CRDL thermally expands and causes the control rods to be inserted further down into the active core region, providing a negative reactivity feedback. Since the control rods are attached to the top of the vessel head and the core attaches to the bottom of the reactor vessel (RV), the expansion of the vessel wall as it heats will either lower the core or raise the control rods supports. This contrary thermal expansion of the reactor vessel wall pulls the control rods out of the core somewhat, providing a positive reactivity feedback. However this is not a safety factor early in a transient because its time constant is relatively large. The total elongated length is calculated by subtracting the vessel expansion from the CRDL expansion to determine the net control rod expansion into the core. The system-wide safety analysis code SSC-K includes the CRDL/RV reactivity feedback model in which control rod and vessel expansions are calculated using single-nod temperatures for the vessel and CRDL masses. The KALIMER design has the upper internal structures (UIS) in which the CRDLs are positioned outside the structure where they are exposed to the mixed sodium temperature exiting the core. A new method to determine the CRDL expansion is suggested. Two dimensional hot pool thermal hydraulic model (HP2D) originally developed for the analysis of the stratification phenomena in the hot pool is utilized for a detailed heat transfer between the CRDL mass and the hot pool coolant. However, the reactor vessel wall temperature is still calculated by a simple lumped model.

  7. Control rod worth calculations using deterministic and stochastic methods

    Energy Technology Data Exchange (ETDEWEB)

    Varvayanni, M. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Savva, P., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece)

    2009-11-15

    Knowledge of the efficiency of a control rod to absorb excess reactivity in a nuclear reactor, i.e. knowledge of its reactivity worth, is very important from many points of view. These include the analysis and the assessment of the shutdown margin of new core configurations (upgrade, conversion, refuelling, etc.) as well as several operational needs, such as calibration of the control rods, e.g. in case that reactivity insertion experiments are planned. The control rod worth can be assessed either experimentally or theoretically, mainly through the utilization of neutronic codes. In the present work two different theoretical approaches, i.e. a deterministic and a stochastic one are used for the estimation of the integral and the differential worth of two control rods utilized in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system SCALE (modules NITAWL/XSDRNPM) and CITATION is used, while the stochastic one is made using the Monte Carlo code TRIPOLI. Both approaches follow the procedure of reactivity insertion steps and their results are tested against measurements conducted in the reactor. The goal of this work is to examine the capability of a deterministic code system to reliably simulate the worth of a control rod, based also on comparisons with the detailed Monte Carlo simulation, while various options are tested with respect to the deterministic results' reliability.

  8. Control rod calibration methods for fast breeder reactors applied to Phenix; Les methodes d'etalonnage des barres de commande des reacteurs a neutrons rapides application a Phenix

    Energy Technology Data Exchange (ETDEWEB)

    Lecourt, G

    1998-06-18

    The control and the emergency shutdown of a fast breeder reactor depends essentially on control rods. For this reason, it is imperative to know exactly how much anti reactivity is introduced with the rods in the reactor core. Different methods have been compared in order to see if they are compatible with Phenix reactor. Their limits have been studied. The shadow and anti shadow effects that can the rods make one to the other and then their effective weight of the rods screen have been clarified. (N.C.)

  9. Estimation and control in HTGR fuel rod fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Downing, D J; Bailey, M J

    1980-01-01

    A control algorithm has been derived for a HTGR Fuel Rod Fabrication Process utilizing the method of Box and Jenkins. The estimator is a Kalman filter and is compared with a Least Square estimator and a standard control chart. The effects of system delays are presented.

  10. Experimental Study of Hydraulic Control Rod Drive Mechanism for Passive IN-core Cooling System of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    CAREM 25 (27 MWe safety systems using hydraulic control rod drives (CRD) studied critical issues that were rod drops with interrupted flow [3]. Hydraulic control rod drive suggested fast shutdown condition using a large gap between piston and cylinder in order to fast drop of neutron absorbing rods. A Passive IN-core Cooling system (PINCs) was suggested for safety enhancement of pressurized water reactors (PWR), small modular reactor (SMR), sodium fast reactor (SFR) in UNIST. PINCs consist of hydraulic control rod drive mechanism (Hydraulic CRDM) and hybrid control rod assembly with heat pipe combined with control rod. The schematic diagram of the hydraulic CRDM for PINCs is shown in Fig. 1. The experimental results show the steady state and transient behavior of the upper cylinder at a low pressure and low temperature. The influence of the working fluid temperature and cylinder mass are investigated. Finally, the heat removal between evaporator section and condenser section is compared with or without the hybrid control rod. Heat removal test of the hybrid heat pipe with hydraulic CRDM system showed the heat transfer coefficient of the bundle hybrid control rod and its effect on evaporator pool. The preliminary test both hydraulic CRDM and heat removal system was conducted, which showed the possibility of the in-core hydraulic drive system for application of PINCs.

  11. Fabrication of control rods for the High Flux Isotope Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sease, J.D.

    1998-03-01

    The High Flux Isotope Reactor (HFIR) is a research-type nuclear reactor that was designed and built in the early 1960s and has been in continuous operation since its initial criticality in 1965. Under current plans, the HFIR is expected to continue in operation until 2035. This report updates ORNL/TM-9365, Fabrication Procedure for HFIR Control Plates, which was mainly prepared in the early 1970's but was not issued until 1984, and reflects process changes, lessons learned in the latest control rod fabrication campaign, and suggested process improvements to be considered in future campaigns. Most of the personnel involved with the initial development of the processes and in part campaigns have retired or will retire soon. Because their unlikely availability in future campaigns, emphasis has been placed on providing some explanation of why the processes were selected and some discussions about the importance of controlling critical process parameters. Contained in this report is a description of the function of control rods in the reactor, the brief history of the development of control rod fabrication processes, and a description of procedures used in the fabrication of control rods. A listing of the controlled documents and procedures used in the last fabrication campaigns is referenced in Appendix A.

  12. The improvement of control rod in experimental fast reactor JOYO. The development of a sodium bonded type control rod

    Energy Technology Data Exchange (ETDEWEB)

    Soga, T.; Miyakawa, S.; Mitsugi, T. [Japan Nuclear Cycle Development Inst., Oarai Engineering Center, Irradiation Center, Irradiation and Administration Section, Oarai, Ibaraki (Japan)

    1999-06-01

    Currently, the lifetime of control rods in JOYO is limited by Absorber-Cladding Mechanical Interaction (ACMI) due to swelling of B{sub 4}C(boron carbide) pellets accelerated by relocation of pellet fragments. A sodium bonded type control rod was developed which improves the thermal conductivity by means of charging sodium into the gap between B{sub 4}C and cladding and by utilizing a shroud which wraps the pellet fragments in a thin tube. This new design will be able to enlarge the gap between B{sub 4}C and cladding, without heating B{sub 4}C or fragment relocation, thus extending the life of the control rod. The sodium bonded type will be fabricated as the ninth reload control rods in JOYO. (1) The specification of a sodium bonded type control rod was determined with the wide gap between B{sub 4}C and cladding. In the design simulation, main component temperature were below the maximum limit. And the local heating by helium bubble generated from B{sub 4}C in the sodium gap, was not a serious problem in the analysis which was considered. (2) A structural design for the sodium entrance into the pin was determined. A formula was developed which the limit for sodium charging given physical dimension of the structure and sodium property. Result from sodium out-pile experiments validated the theoretical formula. (3) The analysis of ACMI indicated a lifetime extension of the sodium bonded type by 4.6% in comparison with lifetime of the helium bonded type of 1.6%. This is due to the boron10 burn-up rate being three times higher in the sodium bonded type than in the helium bonded type. To achieve a target burn-up 10% in the future, it will be necessary to modify design based on irradiation data which will be obtained by practical use of the sodium bonded control rods in JOYO. (4) The effects due to Absorber-Cladding Chemical Interaction (ACCI) were reduced by controlling the cladding temperature and chromium coating to the cladding's inner surface. It was confirmed

  13. Boiling water reactor radiation shielded Control Rod Drive Housing Supports

    Energy Technology Data Exchange (ETDEWEB)

    Baversten, B.; Linden, M.J. [ABB Combustion Engineering Nuclear Operations, Windsor, CT (United States)

    1995-03-01

    The Control Rod Drive (CRD) mechanisms are located in the area below the reactor vessel in a Boiling Water Reactor (BWR). Specifically, these CRDs are located between the bottom of the reactor vessel and above an interlocking structure of steel bars and rods, herein identified as CRD Housing Supports. The CRD Housing Supports are designed to limit the travel of a Control Rod and Control Rod Drive in the event that the CRD vessel attachement went to fail, allowing the CRD to be ejected from the vessel. By limiting the travel of the ejected CRD, the supports prevent a nuclear overpower excursion that could occur as a result of the ejected CRD. The Housing Support structure must be disassembled in order to remove CRDs for replacement or maintenance. The disassembly task can require a significant amount of outage time and personnel radiation exposure dependent on the number and location of the CRDs to be changed out. This paper presents a way to minimize personal radiation exposure through the re-design of the Housing Support structure. The following paragraphs also delineate a method of avoiding the awkward, manual, handling of the structure under the reactor vessel during a CRD change out.

  14. Linear motion device and method for inserting and withdrawing control rods

    Science.gov (United States)

    Smith, J.E.

    Disclosed is a linear motion device and more specifically a control rod drive mechanism (CRDM) for inserting and withdrawing control rods into a reactor core. The CRDM and method disclosed is capable of independently and sequentially positioning two sets of control rods with a single motor stator and rotor. The CRDM disclosed can control more than one control rod lead screw without incurring a substantial increase in the size of the mechanism.

  15. A measurement of a control rod drop using an LVDT

    Science.gov (United States)

    Choi, Myoung-Hwan; Kim, Ji-Ho; Huh, Hyung; Yu, Je-Yong; Sohn, Dong-Seong

    2010-03-01

    A control element drive mechanism is a reactor regulating system, which is to insert, withdraw, or maintain a control rod containing neutron-absorbing material within a reactor core to control the reactivity of the reactor. The ball-screw type CEDM for the small and medium research reactor has a spring-hydraulic damper to reduce the impact force due to the free drop of the CEDM. This paper describes the experimental results to obtain the drop characteristics of the CEDM. The tests are performed by using a full-scale structure except the control element assembly, and a drop time and displacement after an impact are measured by using an LVDT. The influences of the rod weight and the drop height on the drop behavior are also estimated on the basis of test results. In case of the longest stroke, the drop time of the control rod is within 4.5 seconds to meet the design requirement. The behavior after the impact shows a general damping motion of the spring-damper system, and the maximum displacement is measured as 15.6 mm.

  16. International symposium on fuel rod simulators: development and application

    Energy Technology Data Exchange (ETDEWEB)

    McCulloch, R.W. (comp.)

    1981-05-01

    Separate abstracts are included for each of the papers presented concerning fuel rod simulator operation and performance; simulator design and evaluation; clad heated fuel rod simulators and fuel rod simulators for cladding investigations; fuel rod simulator components and inspection; and simulator analytical modeling. Ten papers have previously been input to the Energy Data Base.

  17. Characterization of control rod worths and fuel rod power peaking factors in the university of Utah TRIGA Mark I reactor

    Directory of Open Access Journals (Sweden)

    Alroumi Fawaz

    2016-01-01

    Full Text Available Control rod reactivity (worths for the three control rods and fuel rod power peaking factors in the University of Utah research reactor (100 kW TRIGA Mark I are characterized using the AGENT code system and the results described in this paper. These values are compared to the MCNP6 and existing experimental measurements. In addition, the eigenvalue, neutron spatial flux distributions and reaction rates are analyzed and discussed. The AGENT code system is widely benchmarked for various reactor types and complexities in their geometric arrangements of the assemblies and reactor core material distributions. Thus, it is used as a base methodology to evaluate neutronics variables of the research reactor at the University of Utah. With its much shorter computation time than MCNP6, AGENT provides agreement with the MCNP6 within a 0.5 % difference for the eigenvalue and a maximum difference of 10% in the power peaking factor values. Differential and integral control rod worths obtained by AGENT show well agreement with MCNP6 and the theoretical model. However, regulating the control rod worth is somewhat overestimated by both MCNP6 and AGENT models when compared to the experimental/theoretical values. In comparison to MCNP6, the total control rod worths and shutdown margin obtained with AGENT show better agreement to the experimental values.

  18. Analysis of Explanted Magnetically Controlled Growing Rods From Seven UK Spinal Centers.

    Science.gov (United States)

    Joyce, Thomas J; Smith, Simon L; Rushton, Paul R P; Bowey, Andrew J; Gibson, Michael J

    2018-01-01

    Analysis of explanted MAGnetic Expansion Control (MAGEC) growing rods. To analyze explanted MAGEC rods used in management of early onset scoliosis and identify the mode of failure in such cases. Magnetically controlled growing rods are increasingly used as the option of choice for early onset scoliosis. However, being more complex than conventional growing rods they are perhaps more likely to succumb to multifarious failure modes. In addition, metallosis has been reported around failed MAGEC rods. Explanted MAGEC rods from seven UK spinal centers were obtained for independent analysis. Thirty-four MAGEC rods, from 18 children, explanted for reasons including failure of rod lengthening and maximum rod distraction reached, were cut open to allow internal components to be evaluated and assessed. Externally, all MAGEC rods showed localized marks, which were termed "growth marks" as they indicated growth of the rod in vivo, on the extending bar component. After cutting open, titanium wear debris was found inside all 34 (100%) MAGEC rods. Ninety-one percent (31/34) of MAGEC rods showed measurable wear of the extending bar, towards the magnet end. Substantial damage to the radial bearing was seen inside 74% (25/34) of MAGEC rods while O-ring seal failure was seen in 53% (18/34) of cases. In 44% (15/34) of MAGEC rods the drive pin was fractured but this was felt to be an effect of rod failure, not a cause. The combination of high volumes of titanium wear debris alongside O-ring seal damage likely accounts for the metallosis reported clinically around some MAGEC rods. Based on this explant data, a failure mechanism in MAGEC rods due to the natural off axis loading in the spine was proposed. This is the largest data set reporting a complete analysis of explanted MAGEC rods to date. 4.

  19. Results of automatic system implementation for the friction control rods execution in Cofrentes nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, M., E-mail: mpalomo@iqn.upv.es [Universidad Politecnica de Valencia (UPV) (Spain); Urrea, M., E-mail: matias.urrea@iberdrola.es [Iberdrola Generacion S.A. Valencia (Spain). C.N. Cofrentes; Curiel, M., E-mail: m.curiel@lainsa.com [Logistica y Acondicionamientos Industriales (LAINSA), Valencia (Spain); Arnaldos, A., E-mail: a.arnaldos@titaniast.com [TITANIA Servicios Teconologicos, Valencia (Spain)

    2011-07-01

    The purpose of this presentation is to show the obtained results in Cofrentes Nuclear Power Plant (Spain) of Control Rods PCC/24 Friction Test Procedure. In order to perform this, a Control Rod Friction Test System has been developed. Principally, this system consists on software and data acquisition hardware that obtains and analyzes the control rod pressure variation on which the test is being made. The PCC/24 Procedure objective is to detect an excessive friction in the control rod movement that could cause a CRD (Control Rod Drive) movement slower than usual. This test is necessary every time that an anomalous alteration is produced in the reactor core that could affect to a fuel rod, and it is executed before the time measure of control rods rapid scram test of the affected rods. This test has to be carried out to all the reactor control rods and takes valuable time during plant refuelling. So, by means of an automatic system to perform the test, we obtain an important time saving during refuelling. On the other hand, the on-line monitoring of the control rod insertion and changes in differential pressure, permits a control rod operation fast and safe validation. Moreover, an automatic individual report of every rod is generated by the system and a final global result report of the entire test developed in refuelling is generated. The mentioned reports can be attached directly to the procedure documents obtaining an office data processing important saving time.(author)

  20. Results of automatic system implementation for the friction control rods execution in Cofrentes nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Curiel, M. [Logistica y Acondicionamientos Industriales SAU, Sorolla Center, local 10, Av. de las Cortes Valencianas, 46015 Valencia (Spain); Palomo, M. J. [ISIRYM, Universidad Politecnica de Valencia, Camino de Vera s/n, Valencia (Spain); Urrea, M. [Iberdrola Generacion S. A., Central Nuclear Cofrentes, Carretera Almansa Requena s/n, 04662 Cofrentes, Valencia (Spain); Arnaldos, A., E-mail: m.curiel@lainsa.co [TITANIA Servicios Tecnologicos SL, Sorolla Center, local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain)

    2010-10-15

    The purpose of this presentation is to show the obtained results in Cofrentes nuclear power plant (Spain) of control rods Pcc/24 friction test procedure. In order to perform this, a control rod friction test system has been developed. Principally, this system consists on software and data acquisition hardware that obtains and analyzes the control rod pressure variation on which the test is being made. The Pcc/24 procedure objective is to detect an excessive friction in the control rod movement that could cause a control rod drive movement slower than usual. This test is necessary every time that an anomalous alteration is produced in the reactor core that could affect to a fuel rod, and it is executed before the time measure of control rods rapid scram test of the affected rods. This test has to be carried out to all the reactor control rods and takes valuable time during plant refuelling. So, by means of an automatic system to perform the test, we obtain an important time saving during refuelling. On the other hand, the on-line monitoring of the control rod insertion and changes in differential pressure, permits a control rod operation fast and safe validation. Moreover, an automatic individual report of every rod is generated by the system and a final global result report of the entire test developed in refuelling is generated. The mentioned reports can be attached directly to the procedure documents obtaining an office data processing important saving time. (Author)

  1. Shape control of III-V semiconductor nanocrystals: synthesis and properties of InAs quantum rods.

    Science.gov (United States)

    Kan, ShiHai; Aharoni, Assaf; Mokari, Taleb; Banin, Uri

    2004-01-01

    A novel approach for synthesis of soluble semiconductor quantum rods using metal nanoparticles to direct and catalyze one-dimensional growth is developed. The method is useful in particular for III-V semiconductors with cubic lattice, where the utilization of surfactant-controlled rod-growth is not easily realized. The growth takes place via the solution-liquid-solid (SLS) mechanism where proper precursors are injected into a coordinating solvent. Centrifugation is used for separation of rod-fractions with different lengths. The reaction is demonstrated for InAs, InP and GaAs. Focusing on InAs rods as a model system, we examined the effects of the type of metal catalyst, and the tuning of reaction conditions with respect to temperature, concentration, catalyst content and reaction time. Within the three types of metal catalysts used--Au, Ag and In, Au was found to provide the best control for achieving rod-growth even though the melting point of bulk gold is significantly higher then the reaction temperature. The structural properties of the rods were characterized by transmission electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy. Rods have a cubic lattice and grow mainly along the [111] direction. The relative gold content decreases in shorter rods suggesting Au depletion as a cause for limiting the growth. Room and low temperature absorption and photoluminescence measurements show that the band-gap shifts to the red upon increasing rod length revealing strong quantum confinement along the long axis in InAs rods, providing spectral coverage of the near-IR range relevant for telecommunication applications. Emission intensity also decreases with increased rod-length. These length dependent properties manifest the transition from 0D to 1D quantum confined systems.

  2. Control rod system useable for fuel handling in a gas-cooled nuclear reactor

    Science.gov (United States)

    Spurrier, Francis R.

    1976-11-30

    A control rod and its associated drive are used to elevate a complete stack of fuel blocks to a position above the core of a gas-cooled nuclear reactor. A fuel-handling machine grasps the control rod and the drive is unlatched from the rod. The stack and rod are transferred out of the reactor, or to a new location in the reactor, by the fuel-handling machine.

  3. The orphan nuclear hormone receptor ERRβ controls rod photoreceptor survival

    Science.gov (United States)

    Onishi, Akishi; Peng, Guang-Hua; Poth, Erin M.; Lee, Daniel A.; Chen, Jichao; Alexis, Uel; de Melo, Jimmy; Chen, Shiming; Blackshaw, Seth

    2010-01-01

    Mutation of rod photoreceptor-enriched transcription factors is a major cause of inherited blindness. We identified the orphan nuclear hormone receptor estrogen-related receptor β (ERRβ) as selectively expressed in rod photoreceptors. Overexpression of ERRβ induces expression of rod-specific genes in retinas of wild-type as well as Nrl−/− mice, which lack rod photoreceptors. Mutation of ERRβ results in dysfunction and degeneration of rods, whereas inverse agonists of ERRβ trigger rapid rod degeneration, which is rescued by constitutively active mutants of ERRβ. ERRβ coordinates expression of multiple genes that are rate-limiting regulators of ATP generation and consumption in photoreceptors. Furthermore, enhancing ERRβ activity rescues photoreceptor defects that result from loss of the photoreceptor-specific transcription factor Crx. Our findings demonstrate that ERRβ is a critical regulator of rod photoreceptor function and survival, and suggest that ERRβ agonists may be useful in the treatment of certain retinal dystrophies. PMID:20534447

  4. The Interaction Between Control Rods as Estimated by Second-Order One-Group Perturbation Theory

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Rolf

    1966-10-15

    The interaction effect between control rods is an important problem for the reactivity control of a reactor. The approach of second order one-group perturbation theory is shown to be attractive due to its simplicity. Formulas are derived for the fully inserted control rods in a bare reactor. For a single rod we introduce a correction parameter b, which with good approximation is proportional to the strength of the absorber. For two and more rods we introduce an interaction function g(r{sub ij}), which is assumed to depend only on the distance r{sub ij} between the rods. The theoretical expressions are correlated with the results of several experiments in R0, ZEBRA and the Aagesta reactor, as well as with more sophisticated calculations. The approximate formulas are found to give quite good agreement with exact values, but in the case of about 8 or more rods higher-order effects are likely to be important.

  5. Magnetic controlled growth rods versus conventional growing rod systems in the treatment of early onset scoliosis: a cost comparison.

    Science.gov (United States)

    Rolton, Daniel; Richards, Joanna; Nnadi, Colin

    2015-07-01

    To evaluate the cost differences between a conventional growth rod system (CGRS) and magnetic controlled growth rods (MCGR) in treating early onset scoliosis (EOS) over a projected 5 year period. We hypothesise that the high initial outlay for MCGR would be recouped from fewer admissions and surgical procedures over the lifetime of the implant. The costs of all aspects of treatment for 14 patients undergoing conversion from CGRS to MGRS were collected over a 3 year period. The costs of all aspects of each treatment including clinic visits, hospital stay, theatre and complications were calculated and projected over the lifetime of each device. The initial outlay for insertion for MCGR was £12,913 more than the CGRS. There were significant cost savings for each lengthening which projected over the 5 year lifetime amounted to a cost saving of over £8,000 per patient. Magnetic controlled growth rods reduce the need for multiple invasive procedures in the management of EOS. The implant has a significant projected cost saving in comparison to CGRS.

  6. Controllable end shape modification of ZnO nano-arrays/rods by a simple wet chemical etching technique

    Science.gov (United States)

    Sun, Jingchang; Zhao, Ting; Ma, Zhangwei; Li, Ming; Chang, Cheng; Liang, Hongwei; Bian, Jiming; Li, Chengren

    2015-09-01

    The well-aligned ZnO nano-arrays/rods synthesized by a chemical bath deposition method on a highly conductive Si substrate were chemically etched in an ammonia chloride aqueous solution. An obvious end shape modification of ZnO nano-arrays/rods was realized in this report. The hexagonal frustum end of ZnO nano-arrays/rods changed into a pyramid and the diameter of ZnO nano-arrays/rods decreased gradually with the increasing etching time. The evolution mechanism of the wet etching process was discussed based on a proposed evolution model. Photoluminescence measurements indicated that the near band edge emissions of ZnO nano-arrays/rods increased greatly after wet etching. The controllable end shape modification of ZnO nano-arrays/rods on a highly conductive Si substrate by this simple wet etching technique will further explore the application of ZnO in field emission devices and 1D based nano-devices with various end shapes.

  7. Domain Size Control in Self-Assembling Rod-Coil Block Copolymer And Homopolymer Blends

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Y.; Olsen, B.D.; Ganesan, V.; Segalman, R.A.; /UC, Berkeley /LBL, Berkeley /Texas U.

    2007-07-13

    The addition of homopolymers to a self-assembling rod-coil block copolymer is demonstrated to be a flexible route toward domain size control. Molecular weight matched rod-like homopolymers interdigitate with the rod-blocks within their respective lamellae. As a result of the interdigitation, the coil blocks must rearrange to occupy more interfacial area resulting in an unprecedented decrease in domain spacing with increasing rod homopolymers. Conversely coil homopolymers were locally solubilized within the coil microdomain resulting in an increase of domain spacing with increasing coil homopolymers. The mechanisms of homopolymers solubilization are in qualitative agreement with predictions made by self-consistent mean-field theory (SCFT) calculations.

  8. Modeling of Phenix End-of-Life control rod withdrawal benchmark with DYN3D SFR version

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Evgeny; Fridman, Emil [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactor Safety

    2017-06-01

    The reactor dynamics code DYN3D is currently under extension for Sodium cooled Fast Reactor applications. The control rod withdrawal benchmark from the Phenix End-of-Life experiments was selected for verification and validation purposes. This report presents some selected results to demonstrate the feasibility of using DYN3D for steady-state Sodium cooled Fast Reactor analyses.

  9. Inspection operation aid device and method for control rod drives and hydraulic control system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Shun-ichi; Yamamoto, Hiroki; Okuzumi, Naoaki; Ishisato, Shin-ichi

    1995-12-12

    The device of the present invention comprises an input/output device for inputting/outputting various data required for evaluation of integrity, a memorizing/storing device, an information processing device and a display device. Friction data as differential pressure signals of driving hydraulic pressures measured upon inspection/test operation of control rod drives and hydraulic pressure control system are taken into the input/output device. A result of processing for friction signal waveform pattern is calculated. The integrity and abnormality of the control rod drives and the hydraulic pressure system are evaluated using a causal relation between the result of the signal processing for obtained waveform patterns and the intelligence/knowledge of behaviors of the control rod devices and the hydraulic pressure control system thereby providing integrity data. Since the friction data can be calculated automatically by signal waveform pattern processing, there is no need to read the data manually by specialists who take part in the inspection and test. As a result, data on evaluation for integrity and abnormality of the control rod drives and the hydraulic pressure control system can be provided rapidly. (N.H.).

  10. Ultrasound control of magnet growing rod distraction in early onset scoliosis.

    Science.gov (United States)

    Pérez Cervera, T; Lirola Criado, J F; Farrington Rueda, D M

    2016-01-01

    The growing rod technique is currently one of the most common procedures used in the management of early onset scoliosis. However, in order to preserve spine growth and control the deformity it requires frequent surgeries to distract the rods. Magnetically driven growing rods have recently been introduced with same treatment goal, but without the inconvenience of repeated surgical distractions. One of the limitations of this technical advance is an increase in radiation exposure due to the increase in distraction frequency compared to conventional growing rods. An improvement of the original technique is presented, proposing a solution to the inconvenience of multiple radiation exposure using ultrasound technology to control the distraction process of magnetically driven growing rods. Copyright © 2014 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. Final Report: Contractor Readiness Assessment (CRA) for TREAT Fuel Movement and Control Rod Drives Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Rowsell, David Leon [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2015-06-01

    This report documents the Contractor Readiness Assessment (CRA) for TREAT Fuel Movement and Control Rod Drives Isolation. The review followed the approved Plan of Action (POA) and Implementation Plan (IP) using the identified core requirements. The activity was limited scope focusing on the control rod drives functional isolation and fuel element movement. The purpose of this review is to ensure the facility's readiness to move fuel elements thus supporting inspection and functionally isolate the control rod drives to maintain the required shutdown margin.

  12. TREAT (Transient Reactor Test Facility) reactor control rod scram system simulations and testing

    Energy Technology Data Exchange (ETDEWEB)

    Solbrig, C.W.; Stevens, W.W.

    1990-01-01

    Air cylinders moving heavy components (100 to 300 lbs) at high speeds (above 300 in/sec) present a formidable end-cushion-shock problem. With no speed control, the moving components can reach over 600 in/sec if the air cylinder has a 5 ft stroke. This paper presents an overview of a successful upgrade modification to an existing reactor control rod drive design using a computer model to simulate the modified system performance for system design analysis. This design uses a high speed air cylinder to rapidly insert control rods (278 lb moved 5 ft in less than 300 msec) to scram an air-cooled test reactor. Included is information about the computer models developed to simulate high-speed air cylinder operation and a unique new speed control and end cushion design. A patent application is pending with the US Patent Trade Mark Office for this system (DOE case number S-68,622). The evolution of the design, from computer simulations thru operational testing in a test stand (simulating in-reactor operating conditions) to installation and use in the reactor, is also described. 6 figs.

  13. Measurements and analysis of control rod worths in large heterogeneous LMFBR cores

    Energy Technology Data Exchange (ETDEWEB)

    Collins, P.J.; Brumbach, S.B.; Carpenter, S.G.

    1984-01-01

    The ZPPR-13 program provides basic physics data for heterogeneous LMFBR cores of 700 MW(e) size. A number of internal blanket variations were studied and measurements of control rod worths were made in each configuration. The cores are sensitive to asymmetric perturbations and have strong interaction effects between control rods. Calculations with ENDF/B-IV data are within about 5% of experimental values but show systematic variations in accuracy of prediction with location in the core.

  14. Control of vortex breakdown in a closed cylinder with a small rotating rod

    DEFF Research Database (Denmark)

    Lo Jacono, D.; Sørensen, Jens Nørkær; Thompson, M.C.

    2008-01-01

    Effective control of vortex breakdown in a cylinder with a rotating lid was achieved with small rotating rods positioned on the stationary lid. After validation with accurate measurements using a novel stereoscopic particle image velocimetry (SPIV) technique, analysis of numerical simulations usi...... a high-order spectral element method has been undertaken. The effect of a finite length rod creates additional source terms of vorticity as the rod rotates. These additional source terms and their spatial locations influence the occurrence of the vortex breakdown....

  15. Development of dynamic control rod reactivity measurement methodology and computer code system for PWR

    Energy Technology Data Exchange (ETDEWEB)

    Zee, Sung Quun; Lee, Chung Chan; Song, Jae Seung [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-09-01

    In order to apply dynamic control rod reactivity measurement (DCRM) method to domestic nuclear power reactor, the methodology of EPRC, 'Dynamic Reactivity Measurement of Rod Worth', was reviewed. It was also reviewed that items should be improve in three-dimensional kinetics code MASTER, which was developed by Korea Atomic Energy Research Institute, for use in DCRM. The validity of DORT two-dimensional synthesis method to calculate excore detector weighting factor were benchmarked via Yonggwang Unit 3 three-dimensional TORT calculation. The consistency of MASTER static core calculation results using neutron cross sections generated by commercial design tools PHENIX/ANC and DIT/ROCS were also verified via rodded and unrodded radial power distributions and control rod worth comparisons. 14 refs., 28 figs., 3 tabs. (Author)

  16. Estimation of the activity generated by neutron activation in control rods of a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Rodenas, Jose [Departamento de Ingenieria Quimica y Nuclear, Universidad Politecnica de Valencia, Apartado 22012, E-46071 Valencia (Spain)], E-mail: jrodenas@iqn.upv.es; Gallardo, Sergio; Abarca, Agustin; Juan, Violeta [Departamento de Ingenieria Quimica y Nuclear, Universidad Politecnica de Valencia, Apartado 22012, E-46071 Valencia (Spain)

    2010-04-15

    Control rods are activated by neutron reactions into the reactor. The activation is produced mainly in stainless steel and its impurities. The dose produced by this activity is not important inside the reactor, but it has to be taken into account when the rod is withdrawn from the reactor. Activation reactions produced have been modelled by the MCNP5 code based on the Monte Carlo method. The code gives the number of reactions that can be converted into activity.

  17. Application of rod-shaped cellulose nanocrystals in polyacrylamide hydrogels.

    Science.gov (United States)

    Zhou, Chengjun; Wu, Qinglin; Yue, Yiying; Zhang, Quanguo

    2011-01-01

    Rod-shaped cellulose nanocrystals (CNCs) were manufactured and used to reinforce polyacrylamide (PAM) hydrogels through in situ free-radical polymerization. The gelation process of the nanocomposite hydrogels was monitored on a rheometer using oscillatory shear. The chemical structure, morphology, swelling property, and compression strength of the formed gels were investigated. A possible mechanism for forming hydrogels was proposed. The results showed that CNCs accelerated the formation of hydrogels and increased the effective crosslink density of hydrogels. Thus CNCs were not only a reinforcing agent for hydrogel, but also acted as a multifunctional cross-linker for gelation. The shear storage modulus, compression strength and elastic modulus of the nanocomposite hydrogels were significantly improved because of good dispersion of CNCs in PAM as well as enhanced interfacial interaction between these two components. Among the CNC contents used, a loading of 6.7 w/w% led to the maximum mechanical properties for nanocomposite hydrogels. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Zinc oxide hollow micro spheres and nano rods: Synthesis and applications in gas sensor

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, Saba, E-mail: saba_hrb@yahoo.com [Department of Chemistry, University of Sargodha, Sargodha 40100 (Pakistan); Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, 150001 (China); Institute of Advanced Marine Materials, Harbin Engineering University, 150001 (China); Janjua, Muhammad Ramzan Saeed Ashraf, E-mail: Janjua@uos.edu.pk [Department of Chemistry, University of Sargodha, Sargodha 40100 (Pakistan); Ahmad, Tauqeer; Mehmood, Tahir [Department of Chemistry, University of Sargodha, Sargodha 40100 (Pakistan); Li, Songnan [Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, 150001 (China); Jing, Xiaoyan [Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, 150001 (China); Institute of Advanced Marine Materials, Harbin Engineering University, 150001 (China)

    2014-09-15

    Zinc oxide nano rods and micro hollow spheres are successfully fabricated by adopting a simple solvo-thermal approach without employing any surfactant/template by keeping heating time as variable. The prepared products are characterized by using different instruments such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). In order to investigate the morphological dependence on the reaction time, analogous experiments with various reaction times are carried out. Depending upon heating time, different morphological forms have been identified such as hollow microsphere (4 μm to 5 μm) and nano rods with an average diameter of approximately 100 nm. The fabricated materials are also tested for ethanol gas sensor applications and zinc oxide hollow microsphere proven to be an efficient gas sensing materials. Nitrogen adsorption–desorption measurement was performed to understand better performance of zinc oxide micro hollow spheres as effective ethanol gas sensing material. - Graphical abstract: Graphical abstract is represented by zinc oxide sphere (prepared by simple solvothermal approach), its XRD pattern(characterization) and finally its application in gas sensing. - Highlights: • Zinc oxide spheres were prepared by using solvothermal method. • Detailed description of the morphology of microspheres assembled by nano rods. • Formation mechanism of zinc oxide spheres assembled by nano rods. • Zinc oxide spheres and nano rods displayed very good gas sensing ability.

  19. Drop Performance Test of Conceptually Designed Control Rod Assembly for Prototype Generation IV Sodium-cooled Fast Reactor

    OpenAIRE

    Lee, Young-Kyu; Lee, Jae-Han; Kim, Hoe-Woong; Kim, Sung-Kyun; Kim, Jong-Bum

    2017-01-01

    The control rod assembly controls reactor power by adjusting its position during normal operation and shuts down chain reactions by its free drop under scram conditions. Therefore, the drop performance of the control rod assembly is important for the safety of a nuclear reactor. In this study, the drop performance of the conceptually designed control rod assembly for the prototype generation IV sodium-cooled fast reactor that is being developed at the Korea Atomic Energy Research Institute as...

  20. Validation of the Monte Carlo model developed to estimate doses around the irradiated fuel pool produced by activated control rods discharged from a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Abarca, Agustin; Gallardo, Sergio; Rodenas, Jose [Universidad Politecnica de Valencia (Spain). Dept. de Ingenieria Quimica y Nuclear], e-mail: ergalbe@iqn.upv.es

    2009-07-01

    BWR control rods are irradiated into the reactor by the neutron flux and consequently materials composing the rod become activated. When the control rods are withdrawn from the reactor, they must be stored into the spent fuel storage pool of the plant at a certain depth under water. Doses potentially received by plant workers in the area surrounding the pool edges as well as in a platform moving over the water surface should be calculated to assure the adequate protection. Irradiated fuel elements are stored at the bottom of the pool while controls rods are nearer the surface. Therefore, doses out of the pool are mainly produced by activated control rods. The MCNP5 code based on the Monte Carlo method has been applied to model the pool containing hanger devices with irradiated control rods and to estimate dose rates at points of interest. To obtain dose rates on the pool and around it an F4MESH tally has been used. Furthermore, the SSW/SSR technique has been applied in order to strongly reduce the computer time. Results have been compared with measurements in plant in order to validate the model. An interesting application of the validated model is the assessment of doses when some variation is introduced in the distribution of activated material. (author)

  1. Experience with incomplete control rod insertion in fuel with burnup exceeding approximately 40 GWD/MTU

    Energy Technology Data Exchange (ETDEWEB)

    Kee, E. [Houston Lighting & Power Co., Wadworth, TX (United States)

    1997-01-01

    Analysis and measurement experience with fuel assemblies having incomplete control rod insertion at burnups of approximately 40 GWD/MTU is presented. Control rod motion dynamics and simplified structural analyses are presented and compared to measurement data. Fuel assembly growth measurements taken with the plant Refueling Machine Z-Tape are described and presented. Bow measurements (including plug gauging) are described and potential improvements are suggested. The measurements described and analysis performed show that sufficient guide tube bow (either from creep or yield buckling) is present in some high burnup assemblies to stop the control rods before they reach their full limit of travel. Recommendations are made that, if implemented, could improve cost performance related to testing and analysis activities.

  2. Development and the results for the control rods in MKII core of experimental fast reactor Joyo

    Energy Technology Data Exchange (ETDEWEB)

    Miyakawa, Shunichi; Soga, Tomonori; Takatsuto, Hiroshi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1997-07-01

    Since the first control rod design for the Joyo MKII core (about twenty years ago), there have been several challenging improvements; for example, a helium venting mechanism and a flow induced vibration prevention mechanism. Forty-four control rods with these various modifications have been fabricated. To date, thirty-four have been irradiated and the sixteen have been examined. This experience and effort has produced fruitful results: (1) Efficiency and reliability of the diving-bell type Helium venting mechanism. (2) Efficiency of the flow induced vibration prevention mechanism. (3) Efficiency of the improvement for scram damping mechanism. (4) Clarification of absorber-pellet-cladding-mechanical-interaction (ACMI) phenomena and preventive methods. The fourth result listed above has been a subject of investigation for fifteen years in several countries, that is a main phenomena to dominate control rod life time. The results of this investigation of ACMI in absorber elements are discussed. (J.P.N.)

  3. Learning Curve in Monitoring Magnetically Controlled Growing Rod Distractions With Ultrasound.

    Science.gov (United States)

    Cheung, Jason P Y; Yiu, Karen K L; Bow, Cora; Cheung, Prudence W H; Samartzis, Dino; Cheung, Kenneth M C

    2017-09-01

    Prospective study. To determine whether a learning curve exists for ultrasound measurement of magnetically controlled growing rod (MCGR) distractions. For patients managed by MCGRs, close monitoring of interval distraction length gains is important to determine whether the distractions are translating into actual spine growth. Radiographs are the criterion standard for measuring length gains, but ultrasound has been shown to be effective in monitoring distraction lengths without radiation exposure. It is, however, an operator-dependent tool and thus the accuracy of ultrasound measurement of distracted length may improve with experience. This is a prospective correlation analysis of patients who underwent MCGR treatment for scoliosis. The study period was inclusive of 19th February 2013 to 31st March 2015. All subjects were consecutively recruited in a prospective manner. Data regarding date of the distraction visit, and the interval radiograph and ultrasound measurements of the distracted lengths were collected. Only those episodes with both radiograph and ultrasound performed were used for analysis. The mean differences in change of radiograph and ultrasound measurements were plotted to determine correlation differences and to observe for a learning curve. A total of 379 distraction episodes were analyzed. The mean differences between ultrasound and radiograph measurements per distraction episode were -0.3 mm for the right rod and -0.1 mm for the left rod. For learning curve analysis, there were three distinct timepoints in which the difference of correlation became significantly better and were described as clusters. The correlation in the first cluster (19th February 2013 to 15th October 2013) was 0.612 (right rod) and 0.795 (left rod), the second cluster (16th October 2013 to 20th May 2014) was 0.879 (right rod) and 0.918 (left rod), and the third cluster (21st May 2014 to 31st March 2015) was 0.956 (right rod) and 0.932 (left rod). Thus, a plateau was observed

  4. A novel contra propagating ultrasonic flowmeter using glad buffer rods for high temperature measurement. Application to the oil and gas industries

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Demartonne R. [Brasilia Univ., DF (Brazil). Dept. de Engenharia Eletrica; Cheng-Kuei Jen; Yuu Ono [National Research Council (NRC), Quebec (Canada). Industrial Materials Institute

    2005-07-01

    Ultrasonic techniques are attractive for process monitoring and control because they are non-intrusive, robust and inexpensive. Two common concerns limiting the high temperature performance of conventional ultrasonic systems for flow measurement are related to transducers and couplants. A suitable approach to overcoming this drawback is to insert a thermal isolating buffer rod with good ultrasonic performance (e.g., high signal-to-noise ratio). This requirement is important because, a priori, the noises generated in the buffer rod may bury the desired signals, so that no meaningful information is extracted. Besides protecting the ultrasonic transducers from overheating in applications such as high temperature flow measurements, buffer rods are also a solution for the couplant between the probe and tested sample, since their probing end can be directly wetted by fluids. Here, we propose clad buffer rods driven by shear transducers as the main building block of contra propagating ultrasonic flowmeters for high temperature application. It is demonstrated that the superior signal-to-noise ratio exhibit by clad buffer rods compared to the reported non-clad counterparts improve precision in transit-time measurement, leading to more accurate flow speed determination. In addition, it is shown that clad buffer rods generate specific ultrasonic signals for temperature calibration of flowmeters, allowing temperature variation while still measuring accurately the flow speed. These results are of interest for the oil and gas industries. (author)

  5. Degradation in steam of 60 cm-long B4C control rods

    Science.gov (United States)

    Dominguez, C.; Drouan, D.

    2014-08-01

    In the framework of nuclear reactor core meltdown accident studies, the degradation of boron carbide control rod segments exposed to argon/steam atmospheres was investigated up to about 2000 °C in IRSN laboratories. The sequence of the phenomena involved in the degradation has been found to take place as expected. Nevertheless, the ZrO2 oxide layer formed on the outer surface of the guide tube was very protective, significantly delaying and limiting the guide tube failure and therefore the boron carbide pellet oxidation. Contrary to what was expected, the presence of the control rod decreases the hydrogen release instead of increasing it by additional oxidation of boron compounds. Boron contents up to 20 wt.% were measured in metallic mixtures formed during degradation. It was observed that these metallic melts are able to attack the surrounding fuel rods, which could have consequences on fuel degradation and fission product release kinetics during severe accidents.

  6. Structure Optimization Design of the Electronically Controlled Fuel Control Rod System in a Diesel Engine

    Directory of Open Access Journals (Sweden)

    Hui Jin

    2015-01-01

    Full Text Available Poor ride comfort and shorter clutch life span are the key factors restricting the commercialization of automated manual transmission (AMT. For nonelectrically controlled engines or AMT where cooperative control between the engine and the transmission is not realizable, applying electronically controlled fuel control rod systems (ECFCRS is an effective way to solve these problems. By applying design software such as CATIA, Matlab and Simulink, and MSC Adams, a suite of optimization design methods for ECFCRS drive mechanisms are developed here. Based on these new methods, design requirements can be analyzed comprehensively and the design scheme can be modified easily, thus greatly shortening the design cycle. The bench tests and real vehicle tests indicate that the system developed achieves preferable engine speed following-up performance and engine speed regulating performance. The method developed has significance as a reference for developing other vehicle systems.

  7. Quantitative uncertainty and sensitivity analysis of a PWR control rod ejection accident

    Energy Technology Data Exchange (ETDEWEB)

    Pasichnyk, I.; Perin, Y.; Velkov, K. [Gesellschaft flier Anlagen- und Reaktorsicherheit - GRS mbH, Boltzmannstasse 14, 85748 Garching bei Muenchen (Germany)

    2013-07-01

    The paper describes the results of the quantitative Uncertainty and Sensitivity (U/S) Analysis of a Rod Ejection Accident (REA) which is simulated by the coupled system code ATHLET-QUABOX/CUBBOX applying the GRS tool for U/S analysis SUSA/XSUSA. For the present study, a UOX/MOX mixed core loading based on a generic PWR is modeled. A control rod ejection is calculated for two reactor states: Hot Zero Power (HZP) and 30% of nominal power. The worst cases for the rod ejection are determined by steady-state neutronic simulations taking into account the maximum reactivity insertion in the system and the power peaking factor. For the U/S analysis 378 uncertain parameters are identified and quantified (thermal-hydraulic initial and boundary conditions, input parameters and variations of the two-group cross sections). Results for uncertainty and sensitivity analysis are presented for safety important global and local parameters. (authors)

  8. Cutting of Control Rod Guide Tubes and Jet Pumps at Wuergassen NPP/ Germany

    Energy Technology Data Exchange (ETDEWEB)

    Ralf Loock [Framatome ANP GmbH (Germany)

    2006-07-01

    KWW Nuclear Power Plant has been erected and put into operation in the time period 1968 to end of 1971. In 23 years of operation about 73 billions kWh electric power have been generated. The electric rated power was 670 MW. In May 1995 the decommission was started for economical reasons, since April 1997 the demolition is in progress. In autumn 2003 FANP has been called upon to cut the Control Rod Guide Tubes and Jet Pumps. After a 10 months preparatory phase, cutting of the Control Rod Guide Tubes and Jet Pumps was started in September 2004. For radiation protection reasons the Control Rod Guide Tubes and Jet Pumps were cut and packed remote controlled under water. The cutting process had been selected particularly under consideration of radiation protection aspects. A combination of the technologies band sawing and nibbling was assigned for cutting of the Control Rod Guide Tubes and Jet Pumps. The band saw consists of a substructure and of a feed system installed on it. The feed system can be equipped with one or two band saws optionally. A turntable is integrated in the substructure. It is used to support the CRGT respectively the residual piece of the CRGT and to move it out of the cut position after finishing the cutting. After getting the agreement to the specification, the equipment has been designed and manufactured according to the specification preferences. After finishing the internal testing, the factory acceptance test as well as acceptance and functional tests of every facility were carried out. After cold testing being performed successfully, the cutting equipment was installed in the NPP and checked for operational safety additionally. Cutting of the Control Rod Guide Tubes and Jet Pumps has been carried out on two working places inside the fuel element storage pool. During the total project duration on site the processing has been supervised by the radiation protection staff permanently. As a result 110 Control Rod Guide Tubes and 18 Jet Pumps were

  9. Validation of neutron flux redistribution factors in JSI TRIGA reactor due to control rod movements.

    Science.gov (United States)

    Kaiba, Tanja; Žerovnik, Gašper; Jazbec, Anže; Štancar, Žiga; Barbot, Loïc; Fourmentel, Damien; Snoj, Luka

    2015-10-01

    For efficient utilization of research reactors, such as TRIGA Mark II reactor in Ljubljana, it is important to know neutron flux distribution in the reactor as accurately as possible. The focus of this study is on the neutron flux redistributions due to control rod movements. For analyzing neutron flux redistributions, Monte Carlo calculations of fission rate distributions with the JSI TRIGA reactor model at different control rod configurations have been performed. Sensitivity of the detector response due to control rod movement have been studied. Optimal radial and axial positions of the detector have been determined. Measurements of the axial neutron flux distribution using the CEA manufactured fission chambers have been performed. The experiments at different control rod positions were conducted and compared with the MCNP calculations for a fixed detector axial position. In the future, simultaneous on-line measurements with multiple fission chambers will be performed inside the reactor core for a more accurate on-line power monitoring system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Control Rod Drive Mechanism Installed in the Internal of Reactor Pressure Vessel

    Energy Technology Data Exchange (ETDEWEB)

    Choi, M. H.; Choi, S.; Park, J. S.; Lee, J. S.; Kim, D. O.; Hur, N. S.; Hur, H.; Yu, J. Y

    2008-09-15

    This report describes the review results and important technologies related to the in-vessel type control rod drive mechanism. Generally, most of the CRDMs used in the PWR are attached outside of the reactor pressure vessel, and the pernetration of the vessel head can not avoid. However, in-vessel type CRDMs, which are installed inside the reactor vessel, can eliminate the possibility of rod ejection accidents and the penetration of the vessel head, and provide a compact design of the reactor vessel and containment. There are two kinds of in-vessel type CRDM concerning the driving force-driven by a driving motor and by a hydraulic force. Motor driven CRDMs have been mainly investigated in Japan(MRX, IMR, DRX, next generation BWR etc.), and developed the key components such as a canned motor, an integrated rod position indicator, a separating ball-nut and a ball bearing that can operate under the water conditions of a high temperature and pressure. The concept of hydraulically driven CRDMs have been first reported by KWU and Siemens for KWU 200 reactor, and Argentina(CAREM) and China(NHR-5, NHR-200) have been developed the internal CRDM with the piston and cylinder of slightly different geometries. These systems are driven by the hydraulic force which is produced by pumps outside of the reactor vessel and transmitted through a pipe penetrating the reactor vessel, and needs complicated control and piping systems including pumps, valves and pipes etc.. IRIS has been recently decided the internal CRDMs as the reference design, and an analytical and experimental investigations of the hydraulic drive concept are performed by POLIMI in Italy. Also, a small French company, MP98 has been developed a new type of control rods, called 'liquid control rods', where reactivity is controlled by the movement of a liquid absorber in a manometer type device.

  11. Searching for full power control rod patterns in a boiling water reactor using genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Montes, Jose Luis [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: jlmt@nuclear.inin.mx; Ortiz, Juan Jose [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: jjortiz@nuclear.inin.mx; Requena, Ignacio [Departamento Ciencias Computacion e I.A. ETSII, Informatica, Universidad de Granada, C. Daniel Saucedo Aranda s/n. 18071 Granada (Spain)]. E-mail: requena@decsai.ugr.es; Perusquia, Raul [Departamento Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Ocoyoacac, Edo. de Mexico (Mexico)]. E-mail: rpc@nuclear.inin.mx

    2004-11-01

    One of the most important questions related to both safety and economic aspects in a nuclear power reactor operation, is without any doubt its reactivity control. During normal operation of a boiling water reactor, the reactivity control of its core is strongly determined by control rods patterns efficiency. In this paper, GACRP system is proposed based on the concepts of genetic algorithms for full power control rod patterns search. This system was carried out using LVNPP transition cycle characteristics, being applied too to an equilibrium cycle. Several operation scenarios, including core water flow variation throughout the cycle and different target axial power distributions, are considered. Genetic algorithm fitness function includes reactor security parameters, such as MLHGR, MCPR, reactor k{sub eff} and axial power density.

  12. Measurement of oil film thickness for application to elastomeric Stirling engine rod seals

    Science.gov (United States)

    Krauter, A. I.

    1981-01-01

    The rod seal in the Stirling engine has the function of separating high pressure gas from low or ambient pressure oil. An experimental apparatus was designed to measure the oil film thickness distribution for an elastomeric seal in a reciprocating application. Tests were conducted on commercial elastomeric seals having a 76 mm rod and a 3.8 mm axial width. Test conditions included 70 and 90 seal durometers, a sliding velocity of 0.8 m/sec, and a zero pressure gradient across the seal. An acrylic cylinder and a typical synthetic base automotive lubricant were used. The experimental results showed that the effect of seal hardness on the oil film thickness is considerable. A comparison between analytical and experimental oil film profiles for an elastomeric seal during relatively high speed reciprocating motion showed an overall qualitative agreement.

  13. Integrity Evaluation of Control Rod Assembly for Sodium-Cooled Fast Reactor due to Drop Impact

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Seung; Yoon, Kyung Ho; Kim, Hyung Kyu; Cheon, Jin Sik; Lee, Chan Bock [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2017-03-15

    The CA (Control Assembly) of an SFR has a CRA(Control Rod Assembly) with an inner duct and control rod. During an emergency situation, the CRA falls into the duct of the CA for a rapid shut-down. The drop time and impact velocity of the CRA are important parameters with respect to the reactivity insertion time and the structural integrity of the CRA. The objective of this study was to investigate the dynamic behavior and integrity of the CRA owing to a drop impact. The impact analysis of the CRA under normal/abnormal drop conditions was carried out using the commercial FEM code LS-DYNA. Results of the drop impact analysis demonstrated that the CRA maintained structural integrity, and could be safely inserted into the flow hole of the damper under abnormal conditions.

  14. Feasibility study of the University of Utah TRIGA reactor power upgrade in respect to control rod system

    Science.gov (United States)

    Cutic, Avdo

    The objectives of this thesis are twofold: to determine the highest achievable power levels of the current University of Utah TRIG Reactor (UUTR) core configuration with the existing three control rods, and to design the core for higher reactor power by optimizing the control rod worth. For the current core configuration, the maximum reactor power, eigenvalue keff, shutdown margin, and excess reactivity have been measured and calculated. These calculated estimates resulted from thermal power calibrations, and the control rod worth measurements at various power levels. The results were then used as a benchmark to verify the MCNP5 core simulations for the current core and then to design a core for higher reactor power. This study showed that the maximum achievable power with the current core configuration and control rod system is 150kW, which is 50kW higher than the licensed power of the UUTR. The maximum achievable UUTR core power with the existing fuel is determined by optimizing the core configuration and control rod worth, showing that a power upgrade of 500 kW is achievable. However, it requires a new control rod system consisting of a total of four control rods. The cost of such an upgrade is $115,000.

  15. A Novel Control-rod Drive Mechanism via Electromagnetic Levitation in MNSR

    Directory of Open Access Journals (Sweden)

    Divandari Mohammad

    2014-07-01

    Full Text Available In this paper, an electromagnetic levitation system was used with a synchronous motor to navigate the control rod of a small-type research reactor. The result from this prototype magnetic levitation system was in agreement with simulation results. The control system was programmed in MATLAB through open-loop system, closed-loop with state feedback and closed-loop with state feedback integral tracking. The final control system showed the highest performance with a low positioning error. Our results showed that the developed control system has the potential to be used as a reliable actuator in nuclear reactors to satisfy higher performance and safety.

  16. Rod cluster control assemblies and rod cluster control guide tubes: wear and drop time; Grappes de commande et guides de grappes: usure et tempes de chute

    Energy Technology Data Exchange (ETDEWEB)

    Zbinden, M. [Electricite de France (EDF), Direction des Etudes et Recherches, 92 - Clamart (France)

    1997-12-31

    The wear of RCCAs and of RCC guide tubes is due to two quite different mechanisms and the remedies to apply for each case might lead to contradictory solutions: - the impact/sliding wear for the seldom moving RCCAs, namely the shutdown RCCAs, under flow-induced vibrations, - the axial sliding wear for the control rods subjected to the stepping movements ordered by the acting load. In this case the hydraulic sticking forces are those which produce an evolution of the surface states that may increase the drop time. The introduction, an historical survey of the encountered difficulties, is followed by short description of the components and then the paper presents contributions of EDF in the R and D field, which take place in two successive multi-annual projects. Lastly, some information is given about the recent evolutions and new problems as well for impact/sliding wear as for drop time under normal or seismic conditions. (author).

  17. Analysis of dose rates received around the storage pool for irradiated control rods in a BWR nuclear power plant.

    Science.gov (United States)

    Ródenas, J; Abarca, A; Gallardo, S

    2011-08-01

    BWR control rods are activated by neutron reactions in the reactor. The dose produced by this activity can affect workers in the area surrounding the storage pool, where activated rods are stored. Monte Carlo (MC) models for neutron activation and dose assessment around the storage pool have been developed and validated. In this work, the MC models are applied to verify the expected reduction of dose when the irradiated control rod is hanged in an inverted position into the pool. 2010 Elsevier Ltd. All rights reserved.

  18. Measurements of /sup 10/B(n,He) reaction rates in a mockup control rod in ZPPR

    Energy Technology Data Exchange (ETDEWEB)

    Brumbach, S.B.; Collins, P.J.; Oliver, B.M.

    1986-01-01

    This paper reports the first direct measurement of /sup 10/B capture rate in a mockup control rod in a critical assembly. The experiment used the helium accumulation fluence monitor (HAFM) technique. 13 refs.

  19. Drop Performance Test of Conceptually Designed Control Rod Assembly for Prototype Generation IV Sodium-Cooled Fast Reactor

    Directory of Open Access Journals (Sweden)

    Young-Kyu Lee

    2017-06-01

    Full Text Available The control rod assembly controls reactor power by adjusting its position during normal operation and shuts down chain reactions by its free drop under scram conditions. Therefore, the drop performance of the control rod assembly is important for the safety of a nuclear reactor. In this study, the drop performance of the conceptually designed control rod assembly for the prototype generation IV sodium-cooled fast reactor that is being developed at the Korea Atomic Energy Research Institute as a next-generation nuclear reactor was experimentally investigated. For the performance test, the test facility and test procedure were established first, and several free drop performance tests of the control rod assembly under different flow rate conditions were then carried out. Moreover, performance tests under several types and magnitudes of seismic loading conditions were also conducted to investigate the effects of seismic loading on the drop performance of the control rod assembly. The drop time of the conceptually designed control rod assembly for 0% of the tentatively designed flow rate was measured to be 1.527 seconds, and this agrees well with the analytically calculated drop time. It was also observed that the effect of seismic loading on the drop time was not significant.

  20. A benchmark for investigating the radial dependence of C/E for control rod worths in large decoupled cores

    Energy Technology Data Exchange (ETDEWEB)

    Salvatores, M. (CEA Centre d' Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France)); Orechwa, Y. (Argonne National Lab., IL (USA)); Collins, P.J. (Argonne National Lab., Idaho Falls, ID (USA))

    1990-01-01

    The first physics measurements of a heterogeneous core on the critical assembly ZPPR-7 at ANL showed that the C/E ratios with ENDF/B data for the worths of the control rods in the outer bank were several percent higher than those at the inner bank positions. This radial variation in the C/E for the rod worths was further confirmed in the analysis of the large conventional core ZPPR-10, and again in the analysis of the large heterogeneous core series ZPPR-13. In the design of a power reactor, the number of control rods, and their disposition, are determined by calculations. Misprediction of the worth of the control rods can lead to serious economic penalties by restricting the operation of the core. Retrofitting a core to accommodate more worth will be costly and is likely to lead to a non-optimized core. This document provides a discussion of these calculations. 7 refs., 7 figs., 12 tabs.

  1. Measuring device for purging water flow rate in control rod drive

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Hiroshi.

    1993-11-12

    The device of the present invention enables highly accurate measurement for an amount of purging water supplied to control rod drives of a BWR type reactor. That is, purging water is supplied from an inlet of a scram line of the control rod drives. A temperature measuring portion is disposed, for measuring temperature fluctuation of purging water, to a hydropressure control unit for providing pressure and flow rate of water required for supplying the purging water and scram operation. An instrumentation section is disposed for calculating the flow rate of purging water based on the measured data obtained in the section. An output device is disposed for outputting a flow rate value of the purging water based on the result of the calculation obtained therein. With such a constitution, flow rate of the purging water can be measured quantitatively at the hydropressure control unit. Accordingly, influences, such as fluctuation of reactor core temperature are reduced, and accuracy for the measurement of the purging water flow rate is improved. As a result, reactor safety and maintainability can be improved. (I.S.).

  2. Analyses of eigenvalue bias and control rod worths in FFTF (Fast Flux Test Facility)

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, J.V.; Dobbin, K.D.; Wootan, D.W.; Campbell, L.R.

    1987-01-01

    The Fast Flux Test Facility (FFTF) core loading during its ninth operating cycle was significantly different from that of previous cycles because of the presence of the Core Demonstration Experiment (CDE). The CDE consists of a number of axially blanketed fuel assemblies and internal blankets prototypic of advanced oxide cores in Liquid Metal Reactors (LMR). In preparation for the Cycle 9 reload design effort, a careful assessment of control rod worth and reactivity calculations for Cycles 1 through 8 was made. The goal of this study was to establish calculational biases and reduce uncertainties factored into the reload design calculations. These analyses helped assure that the operational objectives for Cycle 9 were met.

  3. Analysis of the burnup of the control rods with the COREMASTER-Presto code; Analisis del quemado de barras de control con el codigo COREMASTER-PRESTO

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, J.L.; Alonso, G.; Perusquia, R.; Montes, J.L.; Hernandez, H. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jlhm@nuclear.inin-mx

    2003-07-01

    An evaluation of the capacity of the COREMASTER-Presto code, to evaluate generically the burnt of the control bars in the Laguna Verde reactors plant (CLV) is made. It was found that the code only reports burnt values of the control rods in MWD/TM, in spite of having with a second order polynomial model, for the conversion to remainder of the Boron-10 (B-10). It was observed that said model is adequate only for burnt smaller to 45,000 MWD/TM. To evaluate the burnt of the control rods it was reproduced the balance cycle of 18 months for the CLV, executing Cm-Presto during 13 consecutive cycles. First without rod burnt, taking this as the base case. Later on, cases with 1, 2 and up to 13 cycles with rod burnt were generated. When comparing results it was observed that the control rods pattern it loses reactivity lineally with the burnt one. By each 10 G Wd/T of burnt of the nucleus it is decreased the reactivity of the pattern rods {approx} 1 pcm in hot condition and of {approx} 20 pcm in cold condition. When burning three cycles those rods more burnt reached the 13,900 MWD/TM, equivalent to 36% of B-10 reduction, near value to 34% proposed by aging in the one lost study of B-10. It was observed that Cm-Presto it doesn't burn the superior node of the control rods when these are completely extracted. A one big lost of B-10, of the order of 50%, it represents only a decrease of 11% of the reactivity value of the rod. One can affirm that even when it is strongly decreased the content of B-10, the rod is continue considering as a black absorber, that is to say, thermal neutron that enters in the neutron rod that is absorbed. (Author)

  4. The Controlled Synthesis of Carbon Tubes and Rods by Template-Assisted Twin Polymerization

    Directory of Open Access Journals (Sweden)

    Falko Böttger-Hiller

    2013-01-01

    Full Text Available The application of porous carbon is versatile. It is used for high-performance catalyst support, electrode material in batteries, and gas storage. In each of these application fields nanostructuring improves the material properties. Supercapacitors store a high energy density. Exactly adapted carbon structures increase the life of lithium batteries and protect catalysts with increasing reaction rate and selectivity. Most of porous carbon materials have a spherical shape. To the best of our knowledge, there is no procedure to synthesize nanostructured cylindrical porous carbon systematically. Here, template glass fibres and SiO2-tubes were modified with nanostructured SiO2/phenolic resin and SiO2/poly(furfuryl alcohol layers by surface twin polymerization (TP of 2,2′-spirobi[4H-1,3,2-benzodioxasiline] and tetrafurfuryloxysilane. Afterwards the SiO2/polymer layer on the template is thermally transformed into a defect-free nanostructured SiO2/carbon layer. After completely removing the SiO2 components microporous carbon tubes or rods are finally achieved. The diameters of the carbon rods and the inner as well as the outer diameter of the carbon tubes are adjustable according to the shape and size of the template. Thus, a huge variety of microporous carbon materials can be easily produced by template-assisted TP.

  5. Validation of the Monte Carlo model developed to assess the activity generated in control rods of a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Rodenas, Jose, E-mail: jrodenas@iqn.upv.e [Departamento de Ingenieria Quimica y Nuclear, Universidad Politecnica de Valencia, Apartado 22012, E-46071 Valencia (Spain); Abarca, Agustin; Gallardo, Sergio [Departamento de Ingenieria Quimica y Nuclear, Universidad Politecnica de Valencia, Apartado 22012, E-46071 Valencia (Spain); Sollet, Eduardo [Servicio de Proteccion Radiologica, Central Nuclear de Cofrentes, Valencia (Spain)

    2010-07-21

    Control rods are activated by neutron reactions into the reactor. The activation is produced mainly in stainless steel and its impurities. The dose produced by this activity is not important inside the reactor, but it has to be taken into account when the rod is withdrawn from it. The neutron activation has been modeled with the MCNP5 code based on the Monte Carlo method. The number of reactions obtained with the code can be converted into activity. In this work, a detailed model of the control rod has been developed considering all its components: handle, tubes, gain, and central core. On the other hand, the rod has been divided into 5 zones in order to consider the different axial exposition to neutron flux into the reactor. Results of the Monte Carlo simulation for the neutron activation constitute a gamma source in the control rod. With this source, applying again the Monte Carlo method, doses at certain distance of the rod have been calculated. Comparison of calculated doses with experimental measurements leads to the validation of the model developed.

  6. Automatic boiling water reactor control rod pattern design using particle swarm optimization algorithm and local search

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Cheng-Der, E-mail: jdwang@iner.gov.tw [Nuclear Engineering Division, Institute of Nuclear Energy Research, No. 1000, Wenhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan, ROC (China); Lin, Chaung [National Tsing Hua University, Department of Engineering and System Science, 101, Section 2, Kuang Fu Road, Hsinchu 30013, Taiwan (China)

    2013-02-15

    Highlights: ► The PSO algorithm was adopted to automatically design a BWR CRP. ► The local search procedure was added to improve the result of PSO algorithm. ► The results show that the obtained CRP is the same good as that in the previous work. -- Abstract: This study developed a method for the automatic design of a boiling water reactor (BWR) control rod pattern (CRP) using the particle swarm optimization (PSO) algorithm. The PSO algorithm is more random compared to the rank-based ant system (RAS) that was used to solve the same BWR CRP design problem in the previous work. In addition, the local search procedure was used to make improvements after PSO, by adding the single control rod (CR) effect. The design goal was to obtain the CRP so that the thermal limits and shutdown margin would satisfy the design requirement and the cycle length, which is implicitly controlled by the axial power distribution, would be acceptable. The results showed that the same acceptable CRP found in the previous work could be obtained.

  7. Effects of B4C control rod degradation under severe accident

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Si-Won; Park, Sang-Gil; Han, Sang-Ku [Atomic Creative Technology Co., Daejeon (Korea, Republic of)

    2016-10-15

    Boron carbide (B4C) is widely used as absorber material in western boiling water reactor (BWR), some PWR, EPR and Russian RBMK and VVERs. B4C oxidation is one of the important phenomena of in-vessel. In the present paper, the main results and knowledge gained regarding the B4C control rod degradation from above mentioned experiments are reviewed and arranged to inform its significance on the severe accident consequences. In this paper, the role of B4C control rod oxidation and the subsequent degradation on the severe accident consequences is reviewed with available literature and report of previous experimental program regarding the B4C oxidation. From this review, it seems that the contribution of this B4C oxidation on the accident progression to the further severe accident situation is not negligible. For the future work, the extensive experimental data interpretation will be performed to assess quantitatively the effect of B4C oxidation and degradation on the various postulated severe accident conditions.

  8. Assessment of the control rods shadow effect in the VENUS-F core

    Directory of Open Access Journals (Sweden)

    Cetnar Jerzy

    2014-12-01

    Full Text Available The partitioning and transmutation (P&T of spent nuclear fuel is an important field of present development of nuclear energy technologies. One of the possible ways to carry out the P&T process is to use the accelerator driven systems (ADS. This technology has been developed within the EURATOM Framework Programmes for several years now. Current research in this field is carried out within the scope of 7th FP project FREYA. Important parts of the project are experiments performed in the GUINEVERE facility devoted to characterising the subcritical core kinetics and development of reactivity monitoring techniques. The present paper considers the effects of control rods use on the core reactivity. In order to carry out the evaluation of the experimental results, it is important to have detailed core characteristics at hand and to take into consideration the differences in the effect of control rods acting separately or together (the so-called shadow effect on both the reactivity value and the measured neutron flux. Also any core asymmetry should be revealed. This goal was achieved by both MCNP simulations and the experimental results. However, in the case of experimental results, the need for calculating respective correction factors was unavoidable.

  9. Azcatl-CRP: An ant colony-based system for searching full power control rod patterns in BWRs

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, Juan Jose [Dpto. Sistemas Nucleares, ININ, Carr. Mexico-Toluca Km. 36.5, Salazar, Edo. de Mexico (Mexico)]. E-mail: jjortiz@nuclear.inin.mx; Requena, Ignacio [Dpto. Ciencias Computacion e I.A. ETSII Informatica, University of Granada, C. Daniel Saucedo Aranda s/n, 18071 Granada (Spain)]. E-mail: requena@decsai.ugr.es

    2006-01-15

    We show a new system named AZCATL-CRP to design full power control rod patterns in BWRs. Azcatl-CRP uses an ant colony system and a reactor core simulator for this purpose. Transition and equilibrium cycles of Laguna Verde Nuclear Power Plant (LVNPP) reactor core in Mexico were used to test Azcatl-CRP. LVNPP has 109 control rods grouped in four sequences and currently uses control cell core (CCC) strategy in its fuel reload design. With CCC method only one sequence is employed for reactivity control at full power operation. Several operation scenarios are considered, including core water flow variation throughout the cycle, target different axial power distributions and Haling conditions. Azcatl-CRP designs control rod patterns (CRP) taking into account safety aspects such as k {sub eff} core value and thermal limits. Axial power distributions are also adjusted to a predetermined power shape.

  10. SDRE Control Applied to the Wheel Speed of a Compressed Air Engine with Crank-Connecting-Rod Mechanism

    Directory of Open Access Journals (Sweden)

    Alexandre de Castro Alves

    2017-01-01

    Full Text Available Renewable energy sources for vehicles have been the motivation of many researches around the world. The reduction of fossil fuels deposits and increase of the pollution in cities bring the need of more efficient and cleaner energy sources. In this way, this work will present the application of a compressed air engine applied to a bicycle. The engine is composed of two pneumatic cylinders connected to the bicycle wheel through a crank-connecting-rod mechanism. In order to control the velocity of the bicycle, a strategy of control composed of two controls was implemented: a feedback and a feedforward control. For feedback control, the State-Dependent Riccati Equation (SDRE control and also a proportional-derivative (PD control are considered, considering three cases for velocity bicycle variation: 10 km/h, 20 km/h, and 30 km/h. The equations of motion of the system were obtained through the Lagrangian energy method. Numerical simulations were performed in order to analyze the dynamics of the system and the efficiency of the controllers.

  11. High patient-parent satisfaction with magnetically controlled growing rod treatment in EOS

    DEFF Research Database (Denmark)

    Skov, Simon Toftgaard; Bünger, Cody

    Background: Magnetic controlled growing rod (MCGR) use is increasing worldwide and was by some considered a revolution in EOS management. Now, reports on MCGR-failures and complications similar to traditional growing rods are being reported but the treatment is still considered to be a major......-lengthening procedure(s). The parents answered a 7 question non-validated questionnaire before lengthening at the day of the procedure. The answers were in a 0-10 numeric scale score. Results: Thirteen patients, median age 11 years (range 6-18) at MCGR treatment. Around the procedure, the physical strain on the patient...... was rated to a mean 0.2 (range 0-1), the psychological strain on the patient was rated to a mean 1.7 (range 0-7), pain was rated to a mean 0.8 (range 0-2), and the anxiety level of the parents was rated to a mean 0.8 (range 0-5) (0 none, 10 highest imaginable). The overall patient/parent satisfaction...

  12. Fuzzy logic modeling and control of steel rod quenching after hot rolling

    Science.gov (United States)

    Giorleo, G.; Memola Capece Minutolo, F.; Sergi, V.

    1997-10-01

    Reinforced concrete rod produced by European Community countries must comply with standards that establish minimum strength and tensile properties along with other technological and geometrical characteristics; however, possible variability within the assigned limits is not specified. Consequently, a number of manufacturing methods are now used, with the result that over time the mechanical properties of these products vary widely. Increased competition has led to the development of new procedures incorporating both process and quality control. One example is a process based on the heat treatment undergone by the metal bars leaving the final stand of the rolling mill train. In this way, the mechanical and technological properties can be graduated, thereby enhancing strength (particularly yield point) without altering the deformability of the material. This procedure does away with the need to alter the chemical composition of the steel used to manufacture the rods. Process adjustment still relies on the experience of the production manager, however. This paper examines the possibility of applying fuzzy logic computer techniques to the heat treatment process in order to render it more rational and independent of operator unreliability.

  13. Mechanical stability of talin rod controls cell migration and substrate sensing

    National Research Council Canada - National Science Library

    Rolle Rahikainen; Magdaléna von Essen; Markus Schaefer; Lei Qi; Latifeh Azizi; Conor Kelly; Teemu O Ihalainen; Bernhard Wehrle-Haller; Martin Bastmeyer; Cai Huang; Vesa P Hytönen

    2017-01-01

    .... Here, by utilizing computationally designed mutations, we demonstrate that stepwise destabilization of the talin rod R3 subdomain decreases cellular traction force generation, which affects talin...

  14. Internal Leakage Fault Detection and Tolerant Control of Single-Rod Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    Jianyong Yao

    2014-01-01

    Full Text Available The integration of internal leakage fault detection and tolerant control for single-rod hydraulic actuators is present in this paper. Fault detection is a potential technique to provide efficient condition monitoring and/or preventive maintenance, and fault tolerant control is a critical method to improve the safety and reliability of hydraulic servo systems. Based on quadratic Lyapunov functions, a performance-oriented fault detection method is proposed, which has a simple structure and is prone to implement in practice. The main feature is that, when a prescribed performance index is satisfied (even a slight fault has occurred, there is no fault alarmed; otherwise (i.e., a severe fault has occurred, the fault is detected and then a fault tolerant controller is activated. The proposed tolerant controller, which is based on the parameter adaptive methodology, is also prone to realize, and the learning mechanism is simple since only the internal leakage is considered in parameter adaptation and thus the persistent exciting (PE condition is easily satisfied. After the activation of the fault tolerant controller, the control performance is gradually recovered. Simulation results on a hydraulic servo system with both abrupt and incipient internal leakage fault demonstrate the effectiveness of the proposed fault detection and tolerant control method.

  15. Effect of aging upon CE and B and W control rod drives

    Energy Technology Data Exchange (ETDEWEB)

    Grove, E.; Gunther, W.

    1992-05-01

    The effect of aging upon the Babcock & Wilcox (B&W) and Combustion Engineering (CE) Control Rod Drive (CRD) systems has been evaluated as part of the US NRC Nuclear Plant Aging Research (NPAR) program. Operating experience data for the 1980--1990 time period was reviewed to identify predominant failure modes, causes, and effects. These results, in conjunction with an assessment of component materials and operating environment, conclude that both systems are susceptible to age degradation. System failures have resulted in significant plant effects, including power reductions, plant shutdowns, scrams, and Engineered Safety Feature (ESF) actuation. Current industry inspection and maintenance practices were assessed. Some of these practices effectively address aging, while others do not.

  16. Effect of aging upon CE and B and W control rod drives

    Energy Technology Data Exchange (ETDEWEB)

    Grove, E.; Gunther, W.

    1992-01-01

    The effect of aging upon the Babcock Wilcox (B W) and Combustion Engineering (CE) Control Rod Drive (CRD) systems has been evaluated as part of the US NRC Nuclear Plant Aging Research (NPAR) program. Operating experience data for the 1980--1990 time period was reviewed to identify predominant failure modes, causes, and effects. These results, in conjunction with an assessment of component materials and operating environment, conclude that both systems are susceptible to age degradation. System failures have resulted in significant plant effects, including power reductions, plant shutdowns, scrams, and Engineered Safety Feature (ESF) actuation. Current industry inspection and maintenance practices were assessed. Some of these practices effectively address aging, while others do not.

  17. OPR1000 Control Rod Drop Accident Simulation using the SPACE Code

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chang Keun; Ha, Sang Jun; Moon, Chan Kook [Korea Hydro and Nuclear Power, Daejeon (Korea, Republic of)

    2012-05-15

    The Korea nuclear industry has developed a best estimated two-phase three-filed thermal-hydraulic analysis code, SPACE (Safety and Performance Analysis Code for Nuclear Power Plants), for safety analysis and design of a PWR (Pressurized Water Reactor). As the first phase, the demo version of the SPACE code was released in March 2010. The code has been verified and improved according to the Validation and Verification (V and V) matrix prepared for the SPACE code as the second phase of the development. In this study, a Control Rod Drop accident has been simulated using the SPACE code as one aspect of the V and V work. The results from this test were compared with tests of the RETRAN and CESEC codes

  18. Control Rod Withdrawal Events Analyses for the Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Ha, Kwiseo; Jeong, Taekyeong; Jeong, Jaeho; Chang, Wonpyo; Lee, Seungwon; An, Sangjun; Lee, Kwilim [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    To confirm the limiting condition, based on the maximum allowable reactivity insertion of 0.3 $, three cases from the end of cycle (EOC) are selected. In addition, assuming the failure of CRSS by earthquake, additional cases is defined at beginning of cycle (BOC). When the CRW occurs, the reactor can be protected by plant protection system (PPS). In this study, PPS mechanism is sequentially studied for all initiating events. For design basis accidents (DBA), the reactor can be scrammed by reactor protection system (RPS). The first and seconds RPS signals are checked during transients. When RPS is failed, so called as anticipated transient without scram (ATWS), the reactor will be protected by diverse protection system (DPS). In this study, in order to analyze various initiating events related control rod withdrawal, four kinds of operating condition is defined. TOP events are analyzed using MARS-LMR. The influence of various plant protection system such as RPS and DPS are investigated.

  19. Recent rod and section mill control systems. Saikin no jomo atsuenki system

    Energy Technology Data Exchange (ETDEWEB)

    Meguro, H.; Aritoshi, T.; Todaka, Y. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1993-10-10

    The present report introduces the recent trend of rod and section mill control systems. It is confirmed that if a GTO pulse width modulation (PWM) inverter is applied as a driving system, the milling characteristics are heightened due to an improvement in speed response performance. It means that the AC drive is substituted for the conventional DC drive by PWM vector control inverter with GTO elements. The AC drive has the advantage of heightening the accuracy and yield of products, and efficiency of facilities. Also as a driving system, development is being made of a GTO cyclone converter which connects a GTO and thyristor in antiparallel, makes the power factor to be 1 and decreases the low order higher harmonics. The control system is composed of computer, man/machine interface and programmable controller. As an advanced control theory on the point of being put to practical use, there are observer theory and H[infinity] theory, both of which belong to the linear control. As a simulation system, prepared are a program to which a mathematical model of rolling process was introduced, and program to be used for supporting the operational confirmation of plants. 5 refs., 7 figs.

  20. Treatment of early-onset scoliosis with a hybrid of a concave magnetic driver (magnetic controlled growth rod) and a contralateral passive sliding rod construct with apical control: preliminary report on 17 cases.

    Science.gov (United States)

    Skov, Simon T; Wijdicks, Sebastiaan P J; Bünger, Cody; Castelein, René M; Li, Haisheng; Kruyt, Moyo C

    2018-01-01

    Magnetic controlled growth rods (MCGRs) are increasingly popular for surgical treatment of severe early-onset scoliosis (EOS), because they allow noninvasive extensions with good growth maintenance. We combined an MCGR with a contralateral passive sliding rod construct with apical control on the convex side to improve efficiency in terms of costs and three-dimensional (3D) correction. To investigate the feasibility, 3D correction, spinal growth, and complications of the apical control MCGR sliding rod hybrid. Two-center retrospective cohort study. A consecutive series of 17 children with EOS from two European spine centers were treated with the hybrid principle: 13 primary cases and 4 conversion cases from other growth instrumentation. Median age at surgery was 9 years (range: 6-18). Median follow-up time was 24 months (range: 12-31). Cobb angles (frontal Cobb, kyphosis, lordosis), rotation, spinal length gain, growth rate, and complications. Radiographs and patient files were reviewed. All the patients received fully financed treatment within the national public health-care systems. Mean preoperative frontal Cobb angle was 59°, reduced postoperatively to 30° and was maintained throughout follow-up. Mean rotation of the apical vertebra improved from 27° to 18°, but was partially lost over time. Kyphosis decreased and lordosis was largely unaltered. Instrumented spine growth was maintained at a mean of 12 mm per year. One child had surgical revision because of progressive trunk shift, unrelated to the technique. The same child fell and sustained T1 and T2 fractures that were treated conservatively. Another child is planned for revision because of MCGR distraction failure. These early results show satisfactory frontal Cobb curve reduction and maintenance of spinal growth after using a new hybrid concept of a single magnetic growth rod and contralateral apical control sliding rods. A single magnetic growth rod in this combination may work equally well as

  1. Fuel rod pressure in nuclear power reactors: Statistical evaluation of the fuel rod internal pressure in LWRs with application to lift-off probability

    Energy Technology Data Exchange (ETDEWEB)

    Jelinek, Tomas

    2001-02-01

    In this thesis, a methodology for quantifying the risk of exceeding the Lift-off limit in nuclear light water power reactors is outlined. Due to fission gas release, the pressure in the gap between the fuel pellets and the cladding increases with burnup of the fuel. An increase in the fuel-clad gap due to clad creep would be expected to result in positive feedback, in the form of higher fuel temperatures, leading to more fission gas release, higher rod pressure, etc, until the cladding breaks. An increase in the fuel-clad gap that leads to this positive feedback is a phenomenon called Lift-off and is a limitation that must be considered in the fuel core management. Lift-off is a consequence of very high internal fuel rod pressure. The internal fuel rod pressure is therefore used as a Lift-off indicator. The internal fuel rod pressure is closely connected to the fission gas release into the fuel rod plenum and is thus used to increase the database. It is concluded that the dominating error source in the prediction of the pressure in Boiling Water Reactors (BWR), is the power history. There is a bias in the fuel pressure prediction that is dependent on the fuel rod position in the fuel assembly for BWRs. A methodology to quantify the risk of the fuel rod internal pressure exceeding a certain limit is developed; the risk is dependent of the pressure prediction and the fuel rod position. The methodology is based on statistical treatment of the discrepancies between predicted and measured fuel rod internal pressures. Finally, a methodology to estimate the Lift-off probability of the whole core is outlined.

  2. Activation calculation of steel of the control rods of TRIGA Mark III reactor; Calculo de activacion del acero de las barras de control del reactor TRIGA Mark III

    Energy Technology Data Exchange (ETDEWEB)

    Garcia M, T.; Cruz G, H. S.; Ruiz C, M. A.; Angeles C, A., E-mail: teodoro.garcia@inin.gob.mx [ININ, Carretera Mexico-Toluca sn, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    In the pool of TRIGA Mark III reactor of the Instituto Nacional de Investigaciones Nucleares (ININ), there are control rods that were removed from the core, and which are currently on shelves of decay. These rods were part of the reactor core when only had fuel standard (from 1968-1989). To conduct a proper activation analysis of the rods, is very important to have well-characterized the materials which are built, elemental composition of the same ones, the atomic densities and weight fractions of the elements that constitute them. To determine the neutron activation of the control rods MCNP5 code was used, this code allows us to have well characterized the radionuclides inventory that were formed during irradiation of the control rods. This work is limited to determining the activation of the steel that is part of the shielding of the control rods, the nuclear fuel that is in the fuel follower does not include. The calculation model of the code will be validated with experimental measurements and calculating the activity of fission products of the fuel follower which will take place at the end of 2014. (Author)

  3. Adhesive plasters. [Patent application; coatings for crucibles, control rods, etc

    Science.gov (United States)

    Holcombe, C.E. Jr.; Swain, R.L.; Banker, J.G.; Edwards, C.C.

    1975-09-26

    Adhesive plaster compositions are provided by treating particles of Y/sub 2/O/sub 3/, Eu/sub 2/O/sub 3/, Gd/sub 2/O/sub 3/, or Nd/sub 2/O/sub 3/ with dilute acid solutions. The resulting compositions were found to harden spontaneously into rigid reticulated masses resembling plaster of Paris. Upon heating, the hardened material is decomposed into the oxide, yet retains the reticulated rigid structure. 1 table.

  4. Sensitivity analysis of an Advanced Gas-cooled Reactor control rod model

    Energy Technology Data Exchange (ETDEWEB)

    Scott, M.; Green, P.L. [Dynamics Research Group, Department of Mechanical Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); O’Driscoll, D. [EDF Energy, Barnett Way, Barnwood, Gloucester GL4 3RS (United Kingdom); Worden, K.; Sims, N.D. [Dynamics Research Group, Department of Mechanical Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

    2016-08-15

    Highlights: • A model was made of the AGR control rod mechanism. • The aim was to better understand the performance when shutting down the reactor. • The model showed good agreement with test data. • Sensitivity analysis was carried out. • The results demonstrated the robustness of the system. - Abstract: A model has been made of the primary shutdown system of an Advanced Gas-cooled Reactor nuclear power station. The aim of this paper is to explore the use of sensitivity analysis techniques on this model. The two motivations for performing sensitivity analysis are to quantify how much individual uncertain parameters are responsible for the model output uncertainty, and to make predictions about what could happen if one or several parameters were to change. Global sensitivity analysis techniques were used based on Gaussian process emulation; the software package GEM-SA was used to calculate the main effects, the main effect index and the total sensitivity index for each parameter and these were compared to local sensitivity analysis results. The results suggest that the system performance is resistant to adverse changes in several parameters at once.

  5. Estimation of dose rate around the spent control rods of a BWR; Estimacion de la rapidez de dosis alrededor de las barras de control gastadas de un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Cancino P, G.

    2016-10-01

    The energy can come from fossil renewable sources (solar (natural gas, oil), wind, hydro, tidal, geothermal, biomass, bio energy and nuclear. Nuclear power can be obtained by fission reactions and fusion (still under investigation) atomic nuclei. Fission, is a partition of a very heavy nucleus (Uranium 235, for example) into two lighter nuclei. Much of the world's electric power is generated from the energy released by fission processes. In a nuclear power reactor, light water as the BWR, there are many important elements that allow safe driving operation, one of them are the elements or control systems, the burnable poison or neutron absorber inherently allow control power reactor. The control rods, which consist mostly of stainless steel and absorbing elements (such as boron carbide, hafnium, cadmium, among others) of thermal neutrons is able to initiate, regulate or stop the reactor power. These, due to the use of depleted burned or absorbing material and therefore reach their lifespan, which can be 15 years or have other values depending on the manufacturer. Control rods worn should be removed, stored or confined in expressly places. Precisely at this stage arises the importance of knowing their radiological condition to manipulate safely and without incident to the people health responsible for conducting these proceedings state arises. This thesis consists in the estimation of the dose rate in spent control rod made of boron carbide, from a typical BWR reactor. It will be estimated by direct radiation measurements with measurement equipment for radiotherapy ionization chamber, in six spent control rods, which were taken at different reactor operating cycles and are in a spent fuel pool. Using bracket electromechanical and electronic equipment for positioning and lifting equipment for radiation measurement around the control rod in the axial and radial arrangement for proper scanning. Finally will be presented a graphic corresponding to the dose

  6. Simulation of a control rod ejection in a VVER-1000 reactor with the program Relap5-3D

    Energy Technology Data Exchange (ETDEWEB)

    Carbajo, J.J.; Gehin, J.C.; Yoder, G.L. [Oak Ridge National Lab., TN (United States); Ivanov, V.K. [Russian Research Centre Kurchatov Inst., Moscow (Russian Federation)

    2001-07-01

    The RELAP5-3D code has been employed to simulate the ejection of a control rod at the Balakovo-4 plant, a VVER-1000 V320 plant located in Russia. The reactor core contains 163 assemblies, three of them Lead Test Assemblies (LTAs) with mixed oxide (MOX) fuel, and the remaining 160 assemblies with UO{sub 2} fuel. The worth of the ejected control rod was $ 0,225 or 142 pcm. Results from point and three-dimensional (3-D) or nodal kinetics calculations are presented. The results from both models are similar with no significant differences. All calculated results are within safety limits, with no fuel melting or cladding failures predicted to occur. (author)

  7. Managing the reactivity excess of the gas turbine-modular helium reactor by burnable poison and control rods

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, Alberto [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)]. E-mail: alby@neutron.kth.se

    2006-01-15

    The gas turbine-modular helium reactor coupled to the deep burn in-core fuel management strategy offers the extraordinary capability to incinerate over 50% of the initial inventory of fissile material. This extraordinary feature, coming from an advanced and well tested fuel element design, which takes advantage of the TRISO particles technology, is maintained while the reactor is loaded with the most different types of fuels. In the present work, we assumed the reactor operating at the equilibrium of the fuel composition, obtained by a 6 years irradiation of light water reactor waste, and we investigated the effects of the introduction of the burnable poison and the control rods; we equipped the core with all the three types of control rods: operational, startup and shutdown ones. We employed as burnable poison natural erbium, due to the {sup 167}Er increasing neutron capture microscopic cross-section in the energy range where the neutron spectrum exhibits the thermal peak; in addition, we utilized boron carbide, with 90% enrichment in {sup 1}B, as the absorption material of the control rods. Concerning the burnable poison studies, we focused on the k {sub eff} value, the {sup 167}Er mass during burnup, the influence of modifying the radius of the BISO particles kernel and the fuel and moderator coefficients of temperature. Concerning the control rods studies, we investigated the reactivity worth, the changes in the neutron flux profile due to a partial insertion, the influence of modifying the radius of the BISO particles kernel and the {beta} {sub eff}, at the beginning of the operation.

  8. Rodding Surgery

    Science.gov (United States)

    ... above-the-knee splint or lightweight plaster or fiberglass splint instead. Bracing may be used after the ... level. Potential Complications Complications from rodding surgery include risks related to:  General anesthesia,  Fractures during the procedure,  ...

  9. On the Rod Drop technique in integral reactivity measures in control banks and reactor safety; Sobre a tecnica de Rod Drop em medidas de reatividade integral em bancos de controle e seguranca de reatores

    Energy Technology Data Exchange (ETDEWEB)

    Stefani, Giovanni Laranjo

    2013-07-01

    This work presents a study on the effect of shading in neutron detectors, when used in measures of reactivity with the rod drop technique. Shading can be understood as a change in the efficiency of the detectors, when it is given in detected neutrons fission occurred in the reactor, more evident in the detectors closest to the bank being inserted. The method of analysis was based on simulations of reactor IPEN/MB-01, using the code CITATION and MCNP program. In both cases, the results were static, showing Neutronic flows in only two situations: before insertion of the control rod and after insertion. The measure of reactivity in this case was achieved using the expression derived from the source jerk technique. In addition to theoretical study, data from a rod drop experiment conducted in the reactor IPEN/MB-01 were also used. In this case, the reactivity was obtained using inverse kinetic method, since experimental data were set of values that vary with time. In all cases, correction factors for the shadowing effect have been proposed. (author)

  10. Fine cutting edge shaped Bi2O3rods/reduced graphene oxide (RGO) composite for supercapacitor and visible-light photocatalytic applications.

    Science.gov (United States)

    Maruthamani, D; Vadivel, S; Kumaravel, M; Saravanakumar, B; Paul, Bappi; Dhar, Siddhartha Sankar; Habibi-Yangjeh, Aziz; Manikandan, A; Ramadoss, Govindarajan

    2017-07-15

    Bi2O3 rods/RGO composite has been synthesized by a simple precipitation and calcination method. The crystallnity, structural, and morphological features were studied by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and high resolution transmission electron microscopy (HR-TEM) techniques. The supercapacitor behavior was studied using cyclic voltammetry, galvanostatic charge discharge and impedance analysis, respectively. The Bi2O3 rods/RGO nanocomposite exhibits a maximum specific capacitance of 1041Fg-1 at a current density of 2Ag-1. The photocatalytic activity of Bi2O3 rods/RGO composite was evaluated by photocatalytic degradation of methylene blue (MB) dye under visible-light irradiation. The enhancement of photocatalytic properties of Bi2O3 rods/RGO composite attributed to the synergistic effect between Bi2O3 rods and graphene sheets which effectively prevents recombination of the photogenerated electron-hole pairs in Bi2O3 rods. The present study provides a new approach in improving the performance of Bi2O3 rods/RGO composite in energy and environmental applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Neutronic design and comparative characteristics of new pin type control rod for 14-MW TRIGA-SSR reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iorgulis, C.; Truta, C. [Institute for Nuclear Research, 0300 Pitesti (Romania)

    2001-07-01

    This paper presents the structural changes of the control rods (CR-s) which will be done in order to manufacture new ones and therefore to replace the original rods and to increase the present safety features of TRIGA 14 MW reactor in Pitesti. Few years ago two CR-s became inoperable due to the combined effect of welding corrosion, water penetration into the absorbent section of the CR and finally the swelling caused from the high internal pressure of the radiolysis-generated gases (gases which accelerated welding corrosion, water penetration, etc). Although safe reactor operation is not yet affected a decision to redesign a new CR was taken, entirely suitable to the general reactor design. The new CR will use boron carbide (same absorbent as in the original one); this baron carbide will be packed in a different way. A set of 16 Incoloy pins filled with a column of boron carbide pellets, leak-tight welded, will be manufactured. These 16 pins will be mounted in a square array with 5 pins on each side of the square (corner pins being the same far two sides). Neutronic analysis on the preliminary design was done using specific computer codes (WIMS, DFA, and MCNP). Reactivity worth of this new rod would be slight less (8%) than that of the original one, but still with full compensation capacity. Helium release analysis showed that gas pressure in the Incoloy tube after 15 years of normal operation would not exceed 57 ATM. (author)

  12. Light emitting composite rods based on porous silicon in ormosils and polymer matrices for optical applications

    Science.gov (United States)

    Naziruddin Khan, M.; Al Dwayyan, A. S.; Aldalbahi, Ali

    2017-06-01

    Porous silicon (PSi) colloidal solution was directly encapsulated in ormosils and polymer sols to develop nanocomposite based rods. PSi is highly crystalline of around 5-8 nm particles size confirmed by Transmission electron microscopy. SEM images indicate that structural morphology of PSi in the ormosils and polymer environment are different. No major effect on infrared property of PSi particles in the Ormosils and polymers are observed. Absorption and emission property of PSi is influenced when the PSi combined in Ormosils and polymer matrix. Significant photoluminescence stability of PSi in the both matrices is found. Subsequently the spontaneous emission of polished PSi composite ormosils and polymer rods were studied under the pico second tunable laser source. The exhibited spontaneous emission is quite significant. Remarkable stability and optically active of PSi particles in polymer over the ormosils is observed over time. Such composites based on PSi in ormosils and polymer may possibly be improved if high concentration of colloidal solution is employed for further optical test under laser.

  13. Nondestructive and Destructive Examination Studies on Removed-from-Service Control Rod Drive Mechanism Penetrations

    Energy Technology Data Exchange (ETDEWEB)

    Cumblidge, Stephen E.; Crawford, Susan L.; Doctor, Steven R.; Seffens, Rob J.; Schuster, George J.; Toloczko, Mychailo B.; Harris, Robert V.; Bruemmer, Stephen M.

    2007-06-07

    Studies conducted at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, focused on assessing the effectiveness of nondestructive examination (NDE) techniques for inspecting control rod drive mechanism (CRDM) nozzles and J-groove weldments. The primary objectives of this work are to provide information to the U.S. Nuclear Regulatory Commission (NRC) on the effectiveness of NDE methods as related to the in-service inspection of CRDM nozzles and J-groove weldments and to enhance the knowledge base of primary water stress corrosion cracking (PWSCC) through destructive characterization of the CRDM assemblies. Two CRDM assemblies were removed from service, decontaminated, and then used in a series of NDE and destructive examination (DE) measurements; this report addresses the following questions: 1) What did each NDE technique detect? 2) What did each NDE technique miss? 3) How accurately did each NDE technique characterize the detected flaws? 4) Why did the NDE techniques perform or not perform? Two CRDM assemblies including the CRDM nozzle, the J-groove weld, buttering, and a portion of the ferritic head material were selected for this study. This report focuses on a CRDM assembly that contained suspected PWSCC, based on in-service inspection data and through-wall leakage. The NDE measurements used to examine the CRDM assembly followed standard industry techniques for conducting in-service inspections of CRDM nozzles and the crown of the J-groove welds and buttering. These techniques included eddy current testing (ET), time-of-flight diffraction ultrasound, and penetrant testing. In addition, laboratory-based NDE methods were employed to conduct inspections of the CRDM assembly with particular emphasis on inspecting the J-groove weld and buttering. These techniques included volumetric ultrasonic inspection of the J-groove weld metal and visual testing via replicant material of the J-groove weld. The results from these NDE studies were used to

  14. Comparative Studies on Friction and Wear Performance between Glass-fiber Reinforced Polyamide 66 Composite and Ductile Irons on Ceramic Al2O3 Counterface in Sucker Rod Centralizer Application

    National Research Council Canada - National Science Library

    Xu, X; Su, Z. G; Liu, S. Y; Shen, Y. S; An, J

    2010-01-01

    The tribological behaviors of three materials for sucker rod centralizer application including glass-fiber reinforced polyamide 66 composite, ductile iron and quenched ductile iron were investigated...

  15. Development of in-vessel type control rod drive mechanism for a innovative small reactor (Contract research)

    Energy Technology Data Exchange (ETDEWEB)

    Yoritsune, Tsutomu; Ishida, Toshihisa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    Although the control rod drive mechanism of an existing large scale light water reactor is generally installed outside the reactor vessel, an in-vessel type control rod drive mechanism (INV-CRDM) is installed inside the reactor vessel. The INV-CRDM contributes to compactness and simplicity of the reactor system, and it can eliminate the possibility of a rod ejection accident. Therefore, INV-CRDM is an important technology adopted in an innovative small reactor. Japan Atomic Energy Research Institute (JAERI) has developed this type of CRDM driven by an electric motor, which can work under high temperature and high pressure water for the advanced marine reactor. On the basis of this research result, a driving motor coil and a bearing were developed to be used under the high temperature steam, severe condition for an innovative small reactor. About the driving motor, we manufactured the driving motor available for high temperature steam and carried out performance test under room temperature atmosphere to confirm the electric characteristic and coolability of the driving coil. With these test results and the past test results under high temperature water, we analyzed and evaluated the electric performance and coolability of the driving coil under high temperature steam. Concerning bearing, we manufactured the test pieces using some candidate material for material characteristic test and carried out the rolling wear test under high temperature steam to select the material. Consequently, we confirmed that performance of the driving coil for the advanced type driving motor, is enough to be used under high temperature steam. And, we evaluated the performance of the bearing and selected the material of the bearing, which can be used under high temperature steam. From these results, we have obtained the prospect that the INV-CRDM can be used for an innovative small reactor under steam atmosphere could be developed. (author)

  16. Development of external coupling for calculation of the control rod worth in terms of burn-up for a WWER-1000 nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Noori-Kalkhoran, Omid, E-mail: o_noori@yahoo.com [Reactor Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Yarizadeh-Beneh, Mehdi [Faculty of Engineering, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Ahangari, Rohollah [Reactor Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of)

    2016-08-15

    Highlights: • Calculation of control rod worth in term of burn-up. • Calculation of differential and integral control rod worth. • Developing an external couple. • Modification of thermal-hydraulic profiles in calculations. - Abstract: One of the main problems relating to operation of a nuclear reactor is its safety and controlling system. The most widely used control systems for thermal reactors are neutron absorbent rods. In this study a code based method has been developed for calculation of integral and differential control rod worth in terms of burn-up for a WWER-1000 nuclear reactor. External coupling of WIMSD-5B, PARCS V2.7 and COBRA-EN has been used for this purpose. WIMSD-5B has been used for cell calculation and handling burn-up of the core in various days. PARCS V2.7 has been used for neutronic calculation of core and critical boron concentration search. Thermal-hydraulic calculation has been performed by COBRA-EN. An external coupling algorithm has been developed by MATLAB to couple and transfer suitable data between these codes in each step. Steady-State Power Picking Factors (PPFs) of the core and control rod worth for different control rod groups have been calculated from Beginning Of Cycle (BOC) to 289.7 Effective Full Power Days (EFPDs) in some steps. Results have been compared with the results of Bushehr Nuclear Power Plant (BNPP) Final Safety Analysis Report (FSAR). The results show a good agreement and confirm the ability of developed coupling in calculation of control rod worth in terms of burn-up.

  17. Broadband Vibration Attenuation Using Hybrid Periodic Rods

    Directory of Open Access Journals (Sweden)

    S. Asiri

    2008-12-01

    Full Text Available This paper presents both theoretically and experimentally a new kind of a broadband vibration isolator. It is a table-like system formed by four parallel hybrid periodic rods connected between two plates. The rods consist of an assembly of periodic cells, each cell being composed of a short rod and piezoelectric inserts. By actively controlling the piezoelectric elements, it is shown that the periodic rods can efficiently attenuate the propagation of vibration from the upper plate to the lower one within critical frequency bands and consequently minimize the effects of transmission of undesirable vibration and sound radiation. In such a system, longitudinal waves can propagate from the vibration source in the upper plate to the lower one along the rods only within specific frequency bands called the "Pass Bands" and wave propagation is efficiently attenuated within other frequency bands called the "Stop Bands". The spectral width of these bands can be tuned according to the nature of the external excitation. The theory governing the operation of this class of vibration isolator is presented and their tunable filtering characteristics are demonstrated experimentally as functions of their design parameters. This concept can be employed in many applications to control the wave propagation and the force transmission of longitudinal vibrations both in the spectral and spatial domains in an attempt to stop/attenuate the propagation of undesirable disturbances.

  18. Analysis of NEA-NSC PWR Uncontrolled Control Rod Withdrawal at Zero Power Benchmark Cases with NODAL3 Code

    Directory of Open Access Journals (Sweden)

    Tagor Malem Sembiring

    2017-01-01

    Full Text Available The in-house coupled neutronic and thermal-hydraulic (N/T-H code of BATAN (National Nuclear Energy Agency of Indonesia, NODAL3, based on the few-group neutron diffusion equation in 3-dimensional geometry using the polynomial nodal method, has been verified with static and transient PWR benchmark cases. This paper reports the verification of NODAL3 code in the NEA-NSC PWR uncontrolled control rods withdrawal at zero power benchmark. The objective of this paper is to determine the accuracy of NODAL3 code in solving the continuously slow and fast reactivity insertions due to single and group of control rod bank withdrawn while the power and temperature increment are limited by the Doppler coefficient. The benchmark is chosen since many organizations participated using various methods and approximations, so the calculation results of NODAL3 can be compared to other codes’ results. The calculated parameters are performed for the steady-state, transient core averaged, and transient hot pellet results. The influence of radial and axial nodes number was investigated for all cases. The results of NODAL3 code are in very good agreement with the reference solutions if the radial and axial nodes number is 2 × 2 and 2 × 18 (total axial layers, respectively.

  19. Using nonlinearity and spatiotemporal property modulation to control effective structural properties: dynamic rods

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel; Blekhman, Iliya I.

    2007-01-01

    the effective propagation speed of long waves by varying the amplitude of a superimposed high-frequency standing wave. It should be possible to change most properties related to structural stiffness, energy dissipation, and equilibrium states this way, by exploiting the general effects of stiffening, biasing......, and smoothening that characterize mechanically high-frequency excited structures. This work explores fundamental issues for spatiotemporally modulated nonlinear materials. First the effective stress-strain relation of a generally nonlinear material with a prescribed HF strain field is derived, discussed......, and exemplified. Then simple approximate analytical expressions are derived for the effective wave speed and natural frequencies for one-dimensional wave propagation in a nonlinear elastic rod, where the spatiotemporal modulation is imposed as a high-frequency standing wave, supposed to be given. Finally the more...

  20. Wear process of control rod, experience feedback; Mecanisme d'usure des crayons de grappe de commande: apports de l'expertise

    Energy Technology Data Exchange (ETDEWEB)

    Cauvin, R.; Gauthier, A. [Electricite de France (EDF), 75 - Paris (France). Exploitation du Parc Nucleaire; Hertz, D. [FRAMATOME, 92 - Paris-La-Defence (France); Zbinden, M.; Lelait, L. [Electricite de France (EDF), 92 - Clamart (France). Direction des Etudes et Recherches

    1998-07-01

    One of the main factors limiting the life time of control rod assemblies is wear of control rod cladding (austenitic stainless steel) on the guidance.To identify the wear mechanism, an expertise was performed on control rods from EDF 900 MW and 1300 MW PW units. All the different types of wear against discontinuous guidance were examined: different shapes, smooth or angular, and different kinetics, from the slowest to the more rapid. Experimental observation techniques were surface examination with Scanning Electron Microscope and metallography on cross sections. Two different modes were identified: impact and sliding. Wear surfaces are very smooth, with a thin oxide layer (thickness less than 1 micron). No strain hardening is observed close to the surface. Thus, wear mechanisms involving high loading levels seem unlikely. As there is no evidence of metal transfer on the wear surface, a wear mechanism by adhesion can be excluded. Experimental observations suggest a corrosion wear mechanism for the control rods wear against discontinuous guidance. Feedback from EDF reactors control rod assemblies operation shows that surface coating by chromium or surface hardening by ion-nitriding reduce wear in discontinuous guidance. An explanation of the protective effect of these surface treatments is proposed. (authors)

  1. Disposal of waste channels and control rods and radioactive waste; Gestion de canales usados y barras de control como residuos radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Alvarez, L.

    2015-07-01

    Iberdrola and ENRESA are jointly developing a project for the characterization and conditioning of around 200 control rods and 70 used channel from Cofrentes Nuclear Power Plant. This treatment line for high level waste with a radiologic inventory that avoids using the El Cabril low level waste repository is new in Spain and incorporates specific features like the option to carry on with the conditioning stage prior to having a licensed package and available storage facility for this type of waste. (Author)

  2. Feasibility study of the university of Utah TRIGA reactor power upgrade - Part I: Neutronics-based study in respect to control rod system requirements and design

    Directory of Open Access Journals (Sweden)

    Ćutić Avdo

    2013-01-01

    Full Text Available We present a summary of extensive studies in determining the highest achievable power level of the current University of Utah TRIGA core configuration in respect to control rod requirements. Although the currently licensed University of Utah TRIGA power of 100 kW provides an excellent setting for a wide range of experiments, we investigate the possibility of increasing the power with the existing fuel elements and core structure. Thus, we have developed numerical models in combination with experimental procedures so as to assess the potential maximum University of Utah TRIGA power with the currently available control rod system and have created feasibility studies for assessing new core configurations that could provide higher core power levels. For the maximum determined power of a new University of Utah TRIGA core arrangement, a new control rod system was proposed.

  3. Calculation of neutron activation of control rods of a nuclear reactor, using MCNP5; Calculo de activacion neutronica de barras de control de un reactor nuclear, utilizando MCNP5

    Energy Technology Data Exchange (ETDEWEB)

    Pena V, J.D.

    2016-07-01

    The control rods of a nuclear reactor are activated by neutron irradiation. The generated activity produces a dose around the rod which is irrelevant inside the reactor, but significant when the rod is withdrawn and placed in a storage pool, because this dose is a potential risk to the surrounding personnel. On the other hand, most of the activation occurs in the stainless steel components of the rod. The Monte Carlo model can reliably determine the activation produced in a stainless steel part exposed to a neutron flux in a reactor and the dose measurement around this part. This thesis presents the Monte Carlo models developed for the activation of the control rods of the TRIGA Mark III reactor of Instituto Nacional de Investigaciones Nucleares (ININ) when only standard fuel was available. Therefore, the validations of the Monte Carlo models are reliable. (Author)

  4. Impact of mesh points number on the accuracy of deterministic calculations of control rods worth for Tehran research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Boustani, Ehsan [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Amirkabir University of Technology, Tehran (Iran, Islamic Republic of). Energy Engineering and Physics Dept.; Khakshournia, Samad [Amirkabir University of Technology, Tehran (Iran, Islamic Republic of). Energy Engineering and Physics Dept.

    2016-12-15

    In this paper two different computational approaches, a deterministic and a stochastic one, were used for calculation of the control rods worth of the Tehran research reactor. For the deterministic approach the MTRPC package composed of the WIMS code and diffusion code CITVAP was used, while for the stochastic one the Monte Carlo code MCNPX was applied. On comparing our results obtained by the Monte Carlo approach and those previously reported in the Safety Analysis Report (SAR) of Tehran research reactor produced by the deterministic approach large discrepancies were seen. To uncover the root cause of these discrepancies, some efforts were made and finally was discerned that the number of spatial mesh points in the deterministic approach was the critical cause of these discrepancies. Therefore, the mesh optimization was performed for different regions of the core such that the results of deterministic approach based on the optimized mesh points have a good agreement with those obtained by the Monte Carlo approach.

  5. PANTHER solution to the NEA-NSC 3-D PWR core transient benchmark. Uncontrolled withdrawal of control rods at zero power

    Energy Technology Data Exchange (ETDEWEB)

    Kuijper, J.C.

    1994-10-01

    This report contains the results of PANTHER calculations for the ``NEA-NSC 3-D PWR Core Transient Benchmark: Uncontrolled Withdrawal of Control Rods at Zero Power``. PANTHER was able to model the benchmark problems without modifications to the code. All the calculations were performed in 3-D. (orig.).

  6. Design, Fabrication, and Characteristic Experiment of a Hybrid Electromagnet for Bottom-mounted Control Rod Drive Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Hyung; Lee, Jin-Haeng; Yoo, Yeon-Sik; Cho, Yeong-Garp; Ryu, Jeong-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    A control rod drive mechanism (CRDM) is located in the reactor pool top (Top-mounted) or a reactivity control mechanism room under the reactor pool bottom (Bottom-mounted). The function of the CRDM is to insert, withdraw, or maintain neutron absorbing material at any required position in the reactor core in order to keep reactivity control of the core. There are so many kinds of CRDMs, such as magnetic-jack type, hydraulic type, rack and pinion type, chain type, and linear or rotary step motor and so on. As a part of a new project, we have completed the design, fabrication, and characteristic experiment of the prototype bottom-mounted CRDM (BMCRDM). The measured carrying capacity of proto-type hybrid electromagnet is approximately 2.8 (kgf) larger than that of 3D-FEM result. The major reasons of the disagreement between the measured and calculated results are as follows. A. B-H Curve differences of ferromagnetic materials B. Fabrication tolerance and the measured maximum temperature at the center of winding for proto-type hybrid electromagnet, 106 .deg. C, appeared to be 5 .deg. C higher than the analytical result. The major reasons of the disagreement between the measured and calculated results are as follows. A. Difficult for exact modeling of winding including impregnated epoxy, coil insulator, and isolator.

  7. Quality Control Applications

    CERN Document Server

    Chorafas, Dimitris N

    2013-01-01

    Quality control is a constant priority in electrical, mechanical, aeronautical, and nuclear engineering – as well as in the vast domain of electronics, from home appliances to computers and telecommunications. Quality Control Applications provides guidance and valuable insight into quality control policies; their methods, their implementation, constant observation and associated technical audits. What has previously been a mostly mathematical topic is translated here for engineers concerned with the practical implementation of quality control. Once the fundamentals of quality control are established, Quality Control Applications goes on to develop this knowledge and explain how to apply it in the most effective way. Techniques are described and supported using relevant, real-life, case studies to provide detail and clarity for those without a mathematical background. Among the many practical examples, two case studies dramatize the importance of quality assurance: A shot-by-shot analysis of the errors made ...

  8. Improvement in Jc performance below liquid nitrogen temperature for SmBa2Cu3Oy superconducting films with BaHfO3 nano-rods controlled by low-temperature growth

    Directory of Open Access Journals (Sweden)

    S. Miura

    2016-01-01

    Full Text Available For use in high-magnetic-field coil-based applications, the critical current density (Jc of REBa2Cu3Oy (REBCO, where RE = rare earth coated conductors must be isotropically improved, with respect to the direction of the magnetic field; these improvements must be realized at the operating conditions of these applications. In this study, improvement of the Jc for various applied directions of magnetic field was achieved by controlling the morphology of the BaHfO3 (BHO nano-rods in a SmBCO film. We fabricated the 3.0 vol. % BHO-doped SmBCO film at a low growth temperature of 720 °C, by using a seed layer technique (Ts = 720 °C film. The low-temperature growth resulted in a morphological change in the BHO nano-rods. In fact, a high number density of (3.1 ± 0.1 × 103 μm−2 of small (diameter: 4 ± 1 nm, discontinuous nano-rods that grew in various directions, was obtained. In Jc measurements, the Jc of the Ts = 720 °C film in all directions of the applied magnetic field was higher than that of the non-doped SmBCO film. The Jcmin (6.4 MA/cm2 of the former was more than 6 times higher than that (1.0 MA/cm2 of the latter at 40 K, under 3 T. The aforementioned results indicated that the discontinuous BHO nano-rods, which occurred with a high number density, exerted a 3D-like flux pinning at the measurement conditions considered. Moreover, at 4.2 K and under 17 T, a flux pinning force density of 1.6 TN/m3 was realized; this value was comparable to the highest value recorded, to date.

  9. Implementation of a methodology to perform the uncertainty and sensitivity analysis of the control rod drop in a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Reyes F, M. del C.

    2015-07-01

    A methodology to perform uncertainty and sensitivity analysis for the cross sections used in a Trace/PARCS coupled model for a control rod drop transient of a BWR-5 reactor was implemented with the neutronics code PARCS. A model of the nuclear reactor detailing all assemblies located in the core was developed. However, the thermohydraulic model designed in Trace was a simple model, where one channel representing all the types of assemblies located in the core, it was located inside a simple vessel model and boundary conditions were established. The thermohydraulic model was coupled with the neutronics model, first for the steady state and then a Control Rod Drop (CRD) transient was performed, in order to carry out the uncertainty and sensitivity analysis. To perform the analysis of the cross sections used in the Trace/PARCS coupled model during the transient, Probability Density Functions (PDFs) were generated for the 22 parameters cross sections selected from the neutronics parameters that PARCS requires, thus obtaining 100 different cases for the Trace/PARCS coupled model, each with a database of different cross sections. All these cases were executed with the coupled model, therefore obtaining 100 different outputs for the CRD transient with special emphasis on 4 responses per output: 1) The reactivity, 2) the percentage of rated power, 3) the average fuel temperature and 4) the average coolant density. For each response during the transient an uncertainty analysis was performed in which the corresponding uncertainty bands were generated. With this analysis it is possible to observe the results ranges of the responses chose by varying the uncertainty parameters selected. This is very useful and important for maintaining the safety in the nuclear power plants, also to verify if the uncertainty band is within of safety margins. The sensitivity analysis complements the uncertainty analysis identifying the parameter or parameters with the most influence on the

  10. Electrically Controlled Optical Metamaterials Based on Dispersions of Nano-Rods

    Science.gov (United States)

    2011-11-15

    dispersion medium Optical metamaterials , liquid crystals, dielectrophoretic effect, transformation optics, cloaking effect 37 Oleg D. Lavrentovich 330 672...point in space and time, suitable for application in devices such as an “optical invisibility cloak ” and an “optical black hole”. We proposed an...designed to avoid a certain region of the medium, one obtains an invisibility cloak , as any object placed within this region would not interact with

  11. INFLUENCE OF DYNAMIC MAGNETIZATION TO IMPROVE THE EFFICIENCY OF ELECTROMAGNETIC-ACOUSTIC TRANSFORMATION WITH WAVEGUIDE CONTROL RODS

    Directory of Open Access Journals (Sweden)

    D. V. Zlobin

    2017-01-01

    Full Text Available The disadvantage of the electromagnetic-acoustic (EMA method receiving ultrasonic waves are low efficiency. The traditional way to enhance its effectiveness is increase the bias field. The aim of the study was research the way to improve the efficiency of the EMA transformation, using a time-varying bias field.The researches held with the help of a specially designed installation that allows the magnetization to be performed by a constant and alternating magnetic field (dynamic bias, synchronously with the passage of the received pulse. The object of the study were rods made of different grades of steel with a diameter of 4–6 mm, in which the symmetrical zero mode S0 of the rod wave was excited by the EMA method (in the frequency range of about 40 kHz. A comparative analysis of the amplitudes and form pulses of multiple reflections during static and dynamic reversal of magnetization and with a full cycle of magnetization reversal conducted.The result of the efficiency measurements EMA reception during static and dynamic bias found a significant (up to 5 times increase in the signal amplitude on the receiving transducer. Taking into account that the main contribution to the excitation mechanism and the reception mechanism made the magnetostrictive effect on low frecuncy, it can assumed that using a dynamic bias field is impacting significant on the effective mobility of magnetic domains (that is changes the dynamic magnetic susceptibility of the material. It is established that it is possible to monitor steel at lower values of the bias field, and, consequently, to reduce the mass dimensions of the magnetic system.Thus, in the course of the researchers found of effect of dynamic bias and effect of dynamic bias increase acoustic pulse amplitude of the signal of the received EMA method. Using this method will improve the quality EMA testing by creating more efficient EMA transducer. Taking into account that the value of the detected effect

  12. Internal leakage fault detection and tolerant control of single-rod hydraulic actuators

    National Research Council Canada - National Science Library

    Yao, Jianyong; Yang, Guichao; Ma, Dawei

    2014-01-01

    ... failures of the system components. Therefore, fault detection and diagnosis (FDD) and fault tolerant control (FTC) of hydraulic systems have received more and more attentions. FDD is a potential technique to provide efficient condition monitoring and/or preventive maintenance for hydraulic systems but is also a very challenging task, as it is extremely...

  13. Laser Ultrasonic System for Surface Crack Visualization in Dissimilar Welds of Control Rod Drive Mechanism Assembly of Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Yun-Shil Choi

    2014-01-01

    Full Text Available In this paper, we propose a J-groove dissimilar weld crack visualization system based on ultrasonic propagation imaging (UPI technology. A full-scale control rod drive mechanism (CRDM assembly specimen was fabricated to verify the proposed system. An ultrasonic sensor was contacted at one point of the inner surface of the reactor vessel head part of the CRDM assembly. Q-switched laser beams were scanned to generate ultrasonic waves around the weld bead. The localization and sizing of the crack were possible by ultrasonic wave propagation imaging. Furthermore, ultrasonic spectral imaging unveiled frequency components of damage-induced waves, while wavelet-transformed ultrasonic propagation imaging enhanced damage visibility by generating a wave propagation video focused on the frequency component of the damage-induced waves. Dual-directional anomalous wave propagation imaging with adjacent wave subtraction was also developed to enhance the crack visibility regardless of crack orientation and wave propagation direction. In conclusion, the full-scale specimen test demonstrated that the multiple damage visualization tools are very effective in the visualization of J-groove dissimilar weld cracks.

  14. Peptidic ligands to control the three-dimensional self-assembly of quantum rods in aqueous media.

    Science.gov (United States)

    Bizien, Thomas; Even-Hernandez, Pascale; Postic, Marie; Mazari, Elsa; Chevance, Soizic; Bondon, Arnaud; Hamon, Cyrille; Troadec, David; Largeau, Ludovic; Dupuis, Christophe; Gosse, Charlie; Artzner, Franck; Marchi, Valérie

    2014-09-24

    The use of peptidic ligands is validated as a generic chemical platform allowing one to finely control the organization in solid phase of semiconductor nanorods originally dispersed in an aqueous media. An original method to generate, on a macroscopic scale and with the desired geometry, three-dimensional supracrystals composed of quantum rods is introduced. In a first step, nanorods are transferred in an aqueous phase thanks to the substitution of the original capping layer by peptidic ligands. Infrared and nuclear magnetic resonance spectroscopy data prove that the exchange is complete; fluorescence spectroscopy demonstrates that the emitter optical properties are not significantly altered; electrophoresis and dynamic light scattering experiments assess the good colloidal stability of the resulting aqueous suspension. In a second step, water evaporation in a microstructured environment yields superstructures with a chosen geometry and in which nanorods obey a smectic B arrangement, as shown by electron microscopy. Incidentally, bulk drying in a capillary tube generates a similar local order, as evidenced by small angle X-ray scattering. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Approach to criticality in cold core of the Unit 1 of the cycle 10 of the Laguna Verde power plant with control rods similar in design to the original ones and the advanced ones; Aproximacion a criticidad en frio de la Unidad 1 del ciclo 10 de la CLV con barras de control de diseno similar al original y avanzadas

    Energy Technology Data Exchange (ETDEWEB)

    Perusquia, R.; Ramirez, J.R.; Ortiz, J.J.; Hernandez, J.L.; Montes, J.L. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: rpc@nuclear.inin.mx

    2004-07-01

    In the Laguna Verde power plant (CLV) worn out control bars have been replacing for control rods of advanced design. At the moment of the 109 rods of similar design to the original of the Unit 1 of the CLV, 14 of them have been substituted with two types of different advanced control rods. The same as the original rods the advanced rods use boron carbide as control element for neutrons, but additionally they use hafnium, to achieve a longer useful half life. The rods of similar design to the original are homogeneous axially on the other hand the advanced presenting several zones. In principle the advanced rods were designed to be neutronically compatible to the original rods. However the differences in the design and of constituents assumed to consider a different performance during the operation. Since the one numbers of advanced bars is growing with the number of cycles of the CLV reactor has requested to the National Institute of Nuclear Research (ININ) to evaluate in detailed form the performance of the control rods. Previously the calculations and analysis of cycle design that that were carried out assumed that control rods should be of similar design as the original. Using the HELIOS/CM-LENDS system, the effect of the inclusion of advanced rods was analyzed in the approximation of the criticality in cold (20 C) in the cycle 10 of the Unit 1. Four scenarios were poposed, where the type of the rod of substitution control is varied. The value of reactivity was calculated for the rods similar in design to the original and for the advanced one. By comparison of these values, it was found that the value of reactivity of the control rods of the advanced design was superior to the value for rods similar to the original ones by 7.6% for one of the advanced designs and of 13.6% for the other one. (Author)

  16. The application of atlantoaxial screw and rod fixation in revision operations for postoperative re-dislocation in children.

    Science.gov (United States)

    Ma, XiangYang; Yin, QingShui; Xia, Hong; Wu, ZengHui; Yang, JinCheng; Liu, JingFa; Xu, JunJie; Qiu, Feng

    2015-03-01

    We evaluate the feasibility, safety, and efficacy of atlantoaxial screw and rod fixation for revision operations in the treatment of re-dislocation after atlantoaxial operations in children. Eight consecutive children with atlantoaxial instability required a revision operation due to atlantoaxial re-dislocation caused by the failure of the initial posterior wire fixation. The children were 5-11 years of age with an average age of 8.5 years. The posterior atlantoaxial screw and rod fixation and fusion operation was then performed. Autograft bones harvested from rib (in 3 patients), local bone (2 patients), and the iliac crest bone (3 patients) were used. There were no complications such as vertebral artery or spinal cord injury during the operations or loosening or fracture of the fixations after the operations. Stability and reduction of the atlantoaxial segments were achieved in all patients postoperatively. Follow-up time was 24-55 months, with an average of 35 months. All patients achieved solid osseous fusion demonstrated on plain radiographs or CT scanning. Atlantoaxial screw and rod fixation is feasible in children and may be considered for use during the initial operation in the treatment of atlantoaxial dislocation in children to minimize the need for a revision operation. If a revision operation is required, atlantoaxial screw-rod fixation is a safe and effective method. Because the anatomical structure is complicated in revision operation patients, CAD-RP technology could guide the the procedures of exposure and screw placement.

  17. CONTROL ROD ROTATING MECHANISM

    Science.gov (United States)

    Baumgarten, A.; Karalis, A.J.

    1961-11-28

    A threaded rotatable shaft is provided which rotates in response to linear movement of a nut, the shaft being surrounded by a pair of bellows members connected to either side of the nut to effectively seal the reactor from leakage and also to store up energy to shut down the reactor in the event of a power failure. (AEC)

  18. Development of a parallel processing couple for calculations of control rod worth in terms of burn-up in a WWER-1000 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Noori-Kalkhoran, Omid; Ahangari, R. [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of). Reactor Research school; Shirani, A.S. [Shahid Beheshti Univ., Tehran (Iran, Islamic Republic of). Faculty of Engineering

    2017-03-15

    In this study a code based method has been developed for calculation of integral and differential control rod worth in terms of burn-up for a WWER-1000 reactor. Parallel processing of WIMSD-5B, PARCS V2.7 and COBRA-EN has been used for this purpose. WIMSD-5B has been used for cell calculation and handling burn-up of core at different days. PARCS V2.7?has been used for neutronic calculation of core and critical boron concentration search. Thermal-hydraulic calculation has been performed by COBRA-EN. A Parallel processing algorithm has been developed by MATLAB to couple and transfer suitable data between these codes in each step. Steady-State Power Picking Factors (PPFs) of the core and Control rod worth have been calculated from Beginning Of Cycle (BOC) to 289.7 Effective full Power Days (EFPDs) in some steps. Results have been compared with Bushehr Nuclear Power Plant (BNPP) Final Safety Analysis Report (FSAR) results. The results show great similarity and confirm the ability of developed coupling in calculation of control rod worth in terms of burn-up.

  19. Calibrating and Controlling the Quantum Efficiency Distribution of Inhomogeneously Broadened Quantum Rods by Using a Mirror Ball

    DEFF Research Database (Denmark)

    Hansen, Per Lunnemann; Rabouw, Freddy T.; van Dijk-Moes, Relinde J. A.

    2013-01-01

    -in-rod emitters. The emitters are of large current interest due to their improved stability and reduced blinking. We retrieve a room-temperature ensemble average quantum efficiency of 0.87 ± 0.08 at a mean lifetime around 20 ns. We confirm a log-normal distribution of decay rates as often assumed in literature...

  20. Tie rod insertion test

    CERN Multimedia

    B. LEVESY

    2002-01-01

    The superconducting coil is inserted in the outer vaccum tank and supported by a set of tie rods. These tie rods are made of titanium alloy. This test reproduce the final insertion of the tie rods inside the outer vacuum tank.

  1. A methodology for obtaining the control rods patterns in a BWR using systems based on ants colonies; Una metodologia para obtener los patrones de barras de control en un BWR usando sistemas basados en colonias de hormigas

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz S, J.J. [Depto. de Sistemas Nucleares, ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Requena R, I. [Universidad de Granada, 18071 Granada (Spain)]. e-mail: jjortiz@nuclear.inin.mx

    2003-07-01

    In this work the AZCATL-PBC system based on a technique of ants colonies for the search of control rods patterns of those reactors of the Nuclear Power station of Laguna Verde (CNLV) is presented. The technique was applied to a transition cycle and one of balance. For both cycles they were compared the k{sub ef} values obtained with a Haling calculation and the control rods pattern proposed by AZCATL-PBC for a burnt one fixed. It was found that the methodology is able to extend the length of the cycle with respect to the Haling prediction, maintaining sure to the reactor. (Author)

  2. From Current Collectors to Electrodes : Aluminium Rod Structures for Three-dimensional Li-ion Micro-battery Applications

    OpenAIRE

    Oltean, Gabriel

    2014-01-01

    The potential use of 3D aluminium nanorod structures as current collectors and negative electrodes for 3D Li-ion micro-batteries was studied based on the use of relatively simple and cost-effective electrochemical and sol-gel deposition techniques. Aluminium rod structures were synthesised by galvanostatic electrodeposition using commercial porous membranes as templates. It was shown that the use of a short (i.e., 50 ms long) potential pulse (i.e., -0.9 V vs. Al3+/Al) applied prior to a pulse...

  3. Investigation of combined free and forced convection in a 2 x 6 rod bundle during controlled flow transients

    Energy Technology Data Exchange (ETDEWEB)

    Bates, J.M.; Khan, E.U.

    1980-10-01

    An experimental study was performed to obtain local fluid velocity and temperature measurements in the mixed (combined free and forced) convection regime for specific flow coastdown transients. A brief investigation of steady-state flows for the purely free-convection regime was also completed. The study was performed using an electrically heated 2 x 6 rod bundle contained in a flow housing. In addition a transient data base was obtained for evaluating the COBRA-WC thermal-hydraulic computer program (a modified version of the COBRA-IV code).

  4. Determination of power peak factor using control rods, ex-core detectors and neural networks; Determinacao do fator de pico de potencia utilizando barras de controle, detectores ex-core e redes neurais

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Rose Mary Gomes do Prado

    2005-07-01

    This work presents a methodology based on the artificial neural network technique to predict in real time the power peak factor in a form that can be implemented in reactor protection systems. The neural network inputs were those available in the reactor protection systems, namely, the axial and quadrant power differences obtained from measured ex-core detector signals, and the position of control rods. The response of ex core detector signals was measured in experiments especially performed in the IPEN/MB-01 zero-power reactor. Several reactor states with different power density distribution were obtained by positioning the control rods in different configurations. The power distribution and its peak factor were calculated for each of these reactor states using the Citation code. The obtained results show that the power peak factor correlates well with the control rod position and the quadrant power difference, and with a lesser degree with the axial power differences. The data presented an inherent organisation and could be classified into different classes of power peak factor behaviour as a function of position of control rods, axial power difference and quadrant power difference. The RBF networks were able to identify classes and interpolate the power peak factor values. The relative error for the power peak factor estimation ranged from 0.19 % to 0.67 %, less than the one that was obtained performing a power density distribution map with in-core detectors. It was observed that the positions of control rods bear the detailed and localised information about the power density distribution, and that the axial and the quadrant power difference describe its global variations in the axial and radial directions. The results showed that the RBF and MLP networks produced similar results, and that a neural network correlation can be implemented in power reactor protection systems. (author)

  5. Why Rods and Cocci

    Indian Academy of Sciences (India)

    Bacteria exhibit a wide variety of shapes but the commonly studied species of bacteria are generally either spherical in shape which are called cocci (singular coccus) or have a cylindrical shape and are called rods or bacilli (singular bacillus). In reality rods and cocci are the ends of a continuum. Sonle of the cocci are.

  6. Sucker rod string design of the pumping systems

    Directory of Open Access Journals (Sweden)

    Chun Hua Liu

    2015-05-01

    Full Text Available The existing design of sucker rod string mainly focuses on the simplifying assumptions that rod string was exposed to simple tension loading. And its goal was to have equal modified stress at the top of each taper. The improved rod design was to have the same degree of safety at each section, and it used a dynamic force distribution that was proportional along the whole string. However, the available procedures did not provide the desired accuracy of its pertinent analysis, and the operators could not identify the specific phenomena that occur in CBM wells. In this paper, the mathematical models of rod loads and string length were developed based on the cyclic nature of rod string loading; the fatigue endurance method is used to design the single rod string; and the tapered rod string is designed to have an equal equivalent stress at the top of each section. Its application characteristics are demonstrated by the example of CBM wells in Ordos Basin. The interpretations of results show that the previous design gave the single rods a larger diameter and the top rods in the string a greater percent than the proposed method. The calculation should concern about inertial, vibration and friction forces to illustrate the elastic force waves travelling in the rod material with the speed of sound. The single string should be designed using fatigue endurance ratings due to asymmetric pulsating tension of rod loading; and the tapered string should involve a balanced design by setting the fatigue endurance at each section equal. A shorter stroke length gives a greater rod taper percentage and an increased load capacity results to an enhanced rod diameter. The rod diameter increases with the pump size and load capacity for the single string, and the rod taper percentage of the top rod strings increases with plunger diameter for the tapered string. The proposed research improves efficiency of the pumping system, assures good operating conditions, and reduces

  7. Sucker rod string design of the pumping systems

    Directory of Open Access Journals (Sweden)

    Chun Hua Liu

    2015-08-01

    Full Text Available The existing design of sucker rod string mainly focuses on the simplifying assumptions that rod string was exposed to simple tension loading. And its goal was to have equal modified stress at the top of each taper. The improved rod design was to have the same degree of safety at each section, and it used a dynamic force distribution that was proportional along the whole string. However, the available procedures did not provide the desired accuracy of its pertinent analysis, and the operators could not identify the specific phenomena that occur in CBM wells. In this paper, the mathematical models of rod loads and string length were developed based on the cyclic nature of rod string loading; the fatigue endurance method is used to design the single rod string; and the tapered rod string is designed to have an equal equivalent stress at the top of each section. Its application characteristics are demonstrated by the example of CBM wells in Ordos Basin. The interpretations of results show that the previous design gave the single rods a larger diameter and the top rods in the string a greater percent than the proposed method. The calculation should concern about inertial, vibration and friction forces to illustrate the elastic force waves travelling in the rod material with the speed of sound. The single string should be designed using fatigue endurance ratings due to asymmetric pulsating tension of rod loading; and the tapered string should involve a balanced design by setting the fatigue endurance at each section equal. A shorter stroke length gives a greater rod taper percentage and an increased load capacity results to an enhanced rod diameter. The rod diameter increases with the pump size and load capacity for the single string, and the rod taper percentage of the top rod strings increases with plunger diameter for the tapered string. The proposed research improves efficiency of the pumping system, assures good operating conditions, and reduces

  8. Control and optimal control theories with applications

    CERN Document Server

    Burghes, D N

    2004-01-01

    This sound introduction to classical and modern control theory concentrates on fundamental concepts. Employing the minimum of mathematical elaboration, it investigates the many applications of control theory to varied and important present-day problems, e.g. economic growth, resource depletion, disease epidemics, exploited population, and rocket trajectories. An original feature is the amount of space devoted to the important and fascinating subject of optimal control. The work is divided into two parts. Part one deals with the control of linear time-continuous systems, using both transfer fun

  9. Physico-chemical characterization of aerosols produced by a PWR control rods vaporization; Caracterisation physico-chimique des aerosols emis par la vaporisation des barres de controles d'un REP

    Energy Technology Data Exchange (ETDEWEB)

    Rabu, B.; Pagano, C.; Tourasse, M. [CEA/Grenoble, DRN/DEC/SECC, 38 (France); Gros d' Aillon, L.; Boucenna, A. [CEA/Grenoble, Dept. de Thermohydraulique et de Physique, DTP, 38 (France); Boulaud, D. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, 91 - Gif-sur-Yvette (France); Dubourg, R. [CEA/Cadarache, Inst. de Protection et de Surete Nucleaire, IPSN/DRS/SEMAR, 13 - Saint-Paul-lez-Durance (France)

    2000-07-01

    During a PWR type reactor accident, the aerosols produced by the vaporization of the control rods condition the released fission products evolution, for instance, the iodine or the tellurium. The EMAIC experiment has to characterize the aerosols emitted during the core degradation. The IPSN and EDF finances this program, realized at the CEA Grenoble. The results should allow the simulation of the aerosols source resulting from the vaporization to introduce in the ASTEC code, serious accident codes system. (A.L.B.)

  10. Monitoring Control Applications at CERN

    CERN Document Server

    Bernard, F; Milcent, H; Petrova, L B; Varela, F

    2011-01-01

    The Industrial Controls and Engineering (EN-ICE) group [1] of the Engineering Department at CERN has produced, and is responsible for the operation of around 60 applications, which control critical processes in the domains of cryogenics, quench protection systems, power interlocks for the Large Hadron Collider and other subsystems of the accelerator complex. These applications require 24/7 operation and a quick reaction to problems. For this reason the EN-ICE group is presently developing the Monitoring Operation of cOntrols Networks (MOON) tool to detect, anticipate and inform of possible anomalies in the integrity of the applications. The tool builds on top of Simatic WinCC Open Architecture (WinCC OA) [2] SCADA and makes usage of the Joint COntrols Project (JCOP) [3] and the UNified INdustrial COntrol System (UNICOS) [4] Frameworks developed at CERN. The tool provides centralized monitoring and software management of the different elements integrating the control systems like Windows and L...

  11. Axial Rod Coupling Design

    National Research Council Canada - National Science Library

    Smith, David R

    2003-01-01

    .... The axial rod and coupling has been designed to withstand external survival loads ( 8.3 kN (1,870 lb) for Ring 5), and to maintain its length to within 7 microns after disassembly and reassembly...

  12. Engine Modelling for Control Applications

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1997-01-01

    In earlier work published by the author and co-authors, a dynamic engine model called a Mean Value Engine Model (MVEM) was developed. This model is physically based and is intended mainly for control applications. In its newer form, it is easy to fit to many different engines and requires little...... engine data for this purpose. It is especially well suited to embedded model applications in engine controllers, such as nonlinear observer based air/fuel ratio and advanced idle speed control. After a brief review of this model, it will be compared with other similar models which can be found...

  13. Neural Networks in Control Applications

    DEFF Research Database (Denmark)

    Sørensen, O.

    The intention of this report is to make a systematic examination of the possibilities of applying neural networks in those technical areas, which are familiar to a control engineer. In other words, the potential of neural networks in control applications is given higher priority than a detailed...... examined, and it appears that considering 'normal' neural network models with, say, 500 samples, the problem of over-fitting is neglible, and therefore it is not taken into consideration afterwards. Numerous model types, often met in control applications, are implemented as neural network models...... Kalmann filter) representing state space description. The potentials of neural networks for control of non-linear processes are also examined, focusing on three different groups of control concepts, all considered as generalizations of known linear control concepts to handle also non-linear processes...

  14. Validation of the ultrasonic and Eddy current techniques to inspect the accommodation of the elements of (CRDH) control rod drive; Validacion de las tecnicas de ultrasonidos y corrientes inducidas para inspeccionar los alojamientos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A.; Gomez, P.; Sanchez, J.; Resa, P.

    2013-07-01

    Tecnatom development in the past with ultrasonic inspection procedures to examine vessels BWR of several Central nuclear (CRDH) control rod drive elements, accommodations. In each case, inspection techniques have relied on both the volume of required test postulated defects. Also, taking into account the possible access to the component, developed mechanical equipments of different characteristics.

  15. Applications of sliding mode control

    CERN Document Server

    Ghommam, Jawhar; Zhu, Quanmin

    2017-01-01

    This book presents essential studies and applications in the context of sliding mode control, highlighting the latest findings from interdisciplinary theoretical studies, ranging from computational algorithm development to representative applications. Readers will learn how to easily tailor the techniques to accommodate their ad hoc applications. To make the content as accessible as possible, the book employs a clear route in each paper, moving from background to motivation, to quantitative development (equations), and lastly to case studies/illustrations/tutorials (simulations, experiences, curves, tables, etc.). Though primarily intended for graduate students, professors and researchers from related fields, the book will also benefit engineers and scientists from industry. .

  16. Outcomes of support rod usage in loop stoma formation.

    Science.gov (United States)

    Whiteley, Ian; Russell, Michael; Nassar, Natasha; Gladman, Marc A

    2016-06-01

    Traditionally, support rods have been used when creating loop stomas in the hope of preventing retraction. However, their effectiveness has not been clearly established. This study aimed to investigate the rate of stoma rod usage and its impact on stoma retraction and complication rates. A prospective cohort of 515 consecutive patients who underwent loop ileostomy/colostomy formation at a tertiary referral colorectal unit in Sydney, Australia were studied. Mortality and unplanned return to theatre rates were calculated. The primary outcome measure of interest was stoma retraction, occurring within 30 days of surgery. Secondary outcome measures included early stoma complications. The 10-year temporal trends for rod usage, stoma retraction, and complications were examined. Mortality occurred in 23 patients (4.1 %) and unplanned return to theatre in 4 patients (0.8 %). Stoma retraction occurred in four patients (0.78 %), all without rods. However, the rate of retraction was similar, irrespective of whether rods were used (P = 0.12). There was a significant decline in the use of rods during the study period (P stoma retraction rates. Early complications occurred in 94/432 patients (21.8 %) and were more likely to occur in patients with rods (64/223 versus 30/209 without rods, P Stoma retraction is a rare complication and its incidence is not significantly affected by the use of support rods. Further, complications are common post-operatively, and the rate appears higher when rods are used. The routine use of rods warrants judicious application. WHAT DOES THIS PAPER ADD TO THE LITERATURE?: It remains unclear whether support rods prevent stoma retraction. This study, the largest to date, confirms that stoma retraction is a rare complication and is not significantly affected by the use of rods. Consequently, routine rod usage cannot be recommended, particularly as it is associated with increased stoma complications.

  17. MONITORING CONTROL APPLICATIONS AT CERN

    CERN Document Server

    Bernard, F; Milcent, H; Petrova, L B; Varlea, F

    2011-01-01

    The Industrial Controls and Engineering (EN-ICE) group [1] of the Engineering Department at CERN has produced, and is responsible for the operation of around 60 applications, which control critical processes in the domains of cryogenics, quench protection systems, power interlocks for the Large Hadron Collider and other sub-systems of the accelerator complex. These applications require 24/7 operation and a quick reaction to problems. For this reason the EN-ICE group is presently developing the Monitoring Operation of cOntrols Networks (MOON) tool to detect, anticipate and inform of possible anomalies in the integrity of the applications. The tool builds on top of Simatic WinCC Open Architecture (WinCC OA) [2] SCADA and makes usage of the Joint COntrols Project (JCOP) [3] and the UNified INdustrial COntrol System (UNICOS) [4] Frameworks developed at CERN. The tool provides centralized monitoring and software management of the different elements integrating the control systems like Windows and Linux servers, PL...

  18. Biomedical applications of control engineering

    CERN Document Server

    Hacısalihzade, Selim S

    2013-01-01

    Biomedical Applications of Control Engineering is a lucidly written textbook for graduate control engin­eering and biomedical engineering students as well as for medical prac­ti­tioners who want to get acquainted with quantitative methods. It is based on decades of experience both in control engineering and clinical practice.   The book begins by reviewing basic concepts of system theory and the modeling process. It then goes on to discuss control engineering application areas like ·         Different models for the human operator, ·         Dosage and timing optimization in oral drug administration, ·         Measuring symptoms of and optimal dopaminergic therapy in Parkinson’s disease, ·         Measure­ment and control of blood glucose le­vels both naturally and by means of external controllers in diabetes, and ·         Control of depth of anaesthesia using inhalational anaesthetic agents like sevoflurane using both fuzzy and state feedback controllers....

  19. Articulated rods – a novel class of molecular rods based on oligospiroketals (OSK

    Directory of Open Access Journals (Sweden)

    Pablo Wessig

    2015-01-01

    Full Text Available We developed a new type of molecular rods consisting of two (or more rigid units linked by a flexible joint. Consequently we called these constructs articulated rods (ARs. The syntheses of ARs were carried out by a flexible and modular approach providing access to a number of compounds with various functionalizations in terminal positions. First applications were presented with pyrene, cinnamoyl and anthracenyl labelled ARs.

  20. Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anna Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Susan L.; Cinson, Anthony D.; MacFarlan, Paul J.; Hanson, Brady D.; Mathews, Royce

    2012-08-01

    The objective of this investigation was to evaluate the efficacy of ultrasonic testing (UT) for primary water leak path assessments of reactor pressure vessel (RPV) upper head penetrations. Operating reactors have experienced leakage when stress corrosion cracking of nickel-based alloy penetrations allowed primary water into the annulus of the interference fit between the penetration and the low-alloy steel RPV head. In this investigation, UT leak path data were acquired for an Alloy 600 control rod drive mechanism nozzle penetration, referred to as Nozzle 63, which was removed from the North Anna Unit 2 reactor when the RPV head was replaced in 2002. In-service inspection prior to the head replacement indicated that Nozzle 63 had a probable leakage path through the interference fit region. Nozzle 63 was examined using a phased-array UT probe with a 5.0-MHz, eight-element annular array. Immersion data were acquired from the nozzle inner diameter surface. The UT data were interpreted by comparing to responses measured on a mockup penetration with known features. Following acquisition of the UT data, Nozzle 63 was destructively examined to determine if the features identified in the UT examination, including leakage paths and crystalline boric acid deposits, could be visually confirmed. Additional measurements of boric acid deposit thickness and low-alloy steel wastage were made to assess how these factors affect the UT response. The implications of these findings for interpreting UT leak path data are described.

  1. Binary TLBO algorithm assisted to investigate the supper scattering plasmonic nano rod

    Science.gov (United States)

    Kaboli, M.; Akhlaghi, M.

    2017-07-01

    A new efficient binary optimization method based Teaching-Learning-Based Optimization (TLBO) algorithm is proposed to design an array of plasmonic nano-rods in order to achieve maximum scattering coefficient spectrum. In binary TLBO (BTLBO), a group of learner consists a matrix with binary entries; control the presence ("1") or the absence ("0") of nano-rods in the array. Simulation results show that scattering coefficient strongly depends on the localized position of nano-particles and non-periodic structures have more appropriate response in term of scattering coefficient. This approach can be useful in optical applications such as plasmonic nano-antenna.

  2. Morphoelastic rods. Part I: A single growing elastic rod

    KAUST Repository

    Moulton, D.E.

    2013-02-01

    A theory for the dynamics and statics of growing elastic rods is presented. First, a single growing rod is considered and the formalism of three-dimensional multiplicative decomposition of morphoelasticity is used to describe the bulk growth of Kirchhoff elastic rods. Possible constitutive laws for growth are discussed and analysed. Second, a rod constrained or glued to a rigid substrate is considered, with the mismatch between the attachment site and the growing rod inducing stress. This stress can eventually lead to instability, bifurcation, and buckling. © 2012 Elsevier Ltd. All rights reserved.

  3. Neural Networks in Control Applications

    DEFF Research Database (Denmark)

    Sørensen, O.

    simulated process and compared. The closing chapter describes some practical experiments, where the different control concepts and training methods are tested on the same practical process operating in very noisy environments. All tests confirm that neural networks also have the potential to be trained......The intention of this report is to make a systematic examination of the possibilities of applying neural networks in those technical areas, which are familiar to a control engineer. In other words, the potential of neural networks in control applications is given higher priority than a detailed...... study of the networks themselves. With this end in view the following restrictions have been made: - Amongst numerous neural network structures, only the Multi Layer Perceptron (a feed-forward network) is applied. - Amongst numerous training algorithms, only four algorithms are examined, all...

  4. Calibration of silicone rubber rods as passive samplers for pesticides at two different flow velocities: Modeling of sampling rates under water boundary layer and polymer control.

    Science.gov (United States)

    Martin, Alexis; Margoum, Christelle; Jolivet, Antoine; Assoumani, Azziz; El Moujahid, Bachir; Randon, Jérôme; Coquery, Marina

    2017-11-28

    There is a need to determine time-weighted average concentrations of polar contaminants such as pesticides by passive sampling in environmental waters. Calibration data for silicone rubber-based passive samplers are lacking for this class of compounds. The calibration data, sampling rate (R s ), and partition coefficient between silicone rubber and water (K sw ) were precisely determined for 23 pesticides and 13 candidate performance reference compounds (PRCs) in a laboratory calibration system over 14 d for 2 water flow velocities, 5 and 20 cm s -1 . The results showed that an in situ exposure duration of 7 d left a silicone rubber rod passive sampler configuration in the linear or curvilinear uptake period for 19 of the pesticides studied. A change in the transport mechanism from polymer control to water boundary layer control was observed for pesticides with a log K sw of approximately 3.3. The PRC candidates were not fully relevant to correct the impact of water flow velocity on R s . We therefore propose an alternative method based on an overall resistance to mass transfer model to adjust R s from laboratory experiments to in situ hydrodynamic conditions. We estimated diffusion coefficients (D s ) and thickness of water boundary layer (δ w ) as adjustable model parameters. Log D s values ranged from -12.13 to -10.07 m 2  s -1 . The estimated δ w value showed a power function correlation with water flow velocity. Environ Toxicol Chem 2018;9999:1-11. © 2017 SETAC. © 2017 SETAC.

  5. Neural Networks in Control Applications

    DEFF Research Database (Denmark)

    Sørensen, O.

    The intention of this report is to make a systematic examination of the possibilities of applying neural networks in those technical areas, which are familiar to a control engineer. In other words, the potential of neural networks in control applications is given higher priority than a detailed...... study of the networks themselves. With this end in view the following restrictions have been made: - Amongst numerous neural network structures, only the Multi Layer Perceptron (a feed-forward network) is applied. - Amongst numerous training algorithms, only four algorithms are examined, all...... in a recursive form (sample updating). The simplest is the Back Probagation Error Algorithm, and the most complex is the recursive Prediction Error Method using a Gauss-Newton search direction. - Over-fitting is often considered to be a serious problem when training neural networks. This problem is specifically...

  6. New models of droplet deposition and entrainment for prediction of CHF in cylindrical rod bundles

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Haibin, E-mail: hb-zhang@xjtu.edu.cn [School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Department of Chemical Engineering, Imperial College, London SW7 2BY (United Kingdom); Hewitt, G.F. [Department of Chemical Engineering, Imperial College, London SW7 2BY (United Kingdom)

    2016-08-15

    Highlights: • New models of droplet deposition and entrainment in rod bundles is developed. • A new phenomenological model to predict the CHF in rod bundles is described. • The present model is well able to predict CHF in rod bundles. - Abstract: In this paper, we present a new set of model of droplet deposition and entrainment in cylindrical rod bundles based on the previously proposed model for annuli (effectively a “one-rod” bundle) (2016a). These models make it possible to evaluate the differences of the rates of droplet deposition and entrainment for the respective rods and for the outer tube by taking into account the geometrical characteristics of the rod bundles. Using these models, a phenomenological model to predict the CHF (critical heat flux) for upward annular flow in vertical rod bundles is described. The performance of the model is tested against the experimental data of Becker et al. (1964) for CHF in 3-rod and 7-rod bundles. These data include tests in which only the rods were heated and data for simultaneous uniform and non-uniform heating of the rods and the outer tube. It was shown that the predicted CHFs by the present model agree well with the experimental data and with the experimental observation that dryout occurred first on the outer rods in 7-rod bundles. It is expected that the methodology used will be generally applicable in the prediction of CHF in rod bundles.

  7. Cone rod dystrophies

    Directory of Open Access Journals (Sweden)

    Hamel Christian P

    2007-02-01

    Full Text Available Abstract Cone rod dystrophies (CRDs (prevalence 1/40,000 are inherited retinal dystrophies that belong to the group of pigmentary retinopathies. CRDs are characterized by retinal pigment deposits visible on fundus examination, predominantly localized to the macular region. In contrast to typical retinitis pigmentosa (RP, also called the rod cone dystrophies (RCDs resulting from the primary loss in rod photoreceptors and later followed by the secondary loss in cone photoreceptors, CRDs reflect the opposite sequence of events. CRD is characterized by primary cone involvement, or, sometimes, by concomitant loss of both cones and rods that explains the predominant symptoms of CRDs: decreased visual acuity, color vision defects, photoaversion and decreased sensitivity in the central visual field, later followed by progressive loss in peripheral vision and night blindness. The clinical course of CRDs is generally more severe and rapid than that of RCDs, leading to earlier legal blindness and disability. At end stage, however, CRDs do not differ from RCDs. CRDs are most frequently non syndromic, but they may also be part of several syndromes, such as Bardet Biedl syndrome and Spinocerebellar Ataxia Type 7 (SCA7. Non syndromic CRDs are genetically heterogeneous (ten cloned genes and three loci have been identified so far. The four major causative genes involved in the pathogenesis of CRDs are ABCA4 (which causes Stargardt disease and also 30 to 60% of autosomal recessive CRDs, CRX and GUCY2D (which are responsible for many reported cases of autosomal dominant CRDs, and RPGR (which causes about 2/3 of X-linked RP and also an undetermined percentage of X-linked CRDs. It is likely that highly deleterious mutations in genes that otherwise cause RP or macular dystrophy may also lead to CRDs. The diagnosis of CRDs is based on clinical history, fundus examination and electroretinogram. Molecular diagnosis can be made for some genes, genetic counseling is

  8. Control rod cluster drop time anomaly Guandong nuclear power station (Daya bay) and Electricite de France nuclear power stations (1450 MWe N4 Series); Anomalie de temps de chute des grappes de controle centrale de guang dong (daya bay) et centrales d`electricite de France (Palier N4-1450 MWE)

    Energy Technology Data Exchange (ETDEWEB)

    Olivera, J.J.; Naury, S.; Tricot, N.; Tran Dai, P.; Gama, J.M.

    1996-12-31

    The anomaly of control rod cluster drop time revealed at Guandong Nuclear Power Station in Daya Bay and in the Chooz B1 pilot unit for the N4 series, led to the replacement of the M1 type control rod cluster guide tubes with 1300 MWe PWR type guide tubes, adapted to the geometry of the Guandong reactors and the 1450 MWe reactors of the N4 series. The comparison of the drop times obtained with the 1300 MWe type control rod cluster guide 1300 MWe type control rod cluster guide tubes gave satisfactory results. These met the safety criterion for N4 series control rod cluster drop times (2.15 under hot shutdown conditions). The drop time tests which will be carried out in middle of and at the end of cycle 1 of Chooz B1 should make it possible to finally validate the solution already successfully implemented at Guandong. However, this anomaly has revealed the limits of representativeness of the experimental test loops with regard to the real reactor configuration. In view of this, it has been deemed necessary to ask Electricite de France to pursue its analysis both on the understanding of the phenomena which led to this anomaly and on the limits of the representativeness of the experimental test loops. (authors).

  9. Pattern selection dynamics in rod eutectics

    Science.gov (United States)

    Serefoglu, Melis

    The cooperative or diffusively coupled growth of multiple phases during solidification is one of the most widely observed and generally important classes of phase transformations in materials. Technologically, low melting temperature and small freezing range contribute to excellent casting fluidity and fine composite structures give rise to favorable properties. Both of these features contribute to the wide application of eutectic alloys in the casting, welding, and soldering of engineered components. Despite the broad-based technological importance, many fundamental questions regarding eutectic solidification remain unanswered, severely limiting our ability to employ computational methods in the prediction of microstructure for the effective design of new materials and processes. At the core of the most persistent questions, lie problems involving multicomponent thermodynamics, solid-liquid and solid-solid interfacial phenomena, morphological stability, chemical and thermal diffusion, and nucleation phenomena. In the current study, pattern selection dynamics in rod eutectics are investigated using systematic directional solidification experiments and phase field simulations. Directional solidification of a succinonitrile-camphor (SCN-DC) transparent alloy in thin slab geometries of various thicknesses reveals two main points. First, a velocity is indentified at which a transition in array basis vectors is observed in specimens with many rows of rods (i.e. bulk). This transition amounts to a 90 degree rotation of the rod array, shifting from alignment of 1st nearest neighbors to alignment of 2nd nearest neighbors along the slide wall. Second, significant array distortion is observed with decreasing slide thickness, delta, which ultimately leads to a single-row (quasi-3D) morphology where delta/lambda is on the order of unity. In our analysis of these observations, we use a geometrical model to describe the rod arrangement as a function of slide thickness, providing

  10. Semiconductor Quantum Rods as Single Molecule FluorescentBiological Labels

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Aihua; Gu, Weiwei; Boussert, Benjamine; Koski, Kristie; Gerion, Daniele; Manna, Liberato; Le Gros, Mark; Larabell, Carolyn; Alivisatos, A. Paul

    2006-05-29

    In recent years, semiconductor quantum dots have beenapplied with great advantage in a wide range of biological imagingapplications. The continuing developments in the synthesis of nanoscalematerials and specifically in the area of colloidal semiconductornanocrystals have created an opportunity to generate a next generation ofbiological labels with complementary or in some cases enhanced propertiescompared to colloidal quantum dots. In this paper, we report thedevelopment of rod shaped semiconductor nanocrystals (quantum rods) asnew fluorescent biological labels. We have engineered biocompatiblequantum rods by surface silanization and have applied them fornon-specific cell tracking as well as specific cellular targeting. Theproperties of quantum rods as demonstrated here are enhanced sensitivityand greater resistance for degradation as compared to quantum dots.Quantum rods have many potential applications as biological labels insituations where their properties offer advantages over quantumdots.

  11. Rewetting of a low superheated rod with saturated water

    Energy Technology Data Exchange (ETDEWEB)

    Portillo, O.; Reyes, R.; Wayner, P.C. Jr.

    1999-07-01

    The study of the rewetting of a superheated surface has application in several technological fields. It is related to the control mechanism for loss of coolant accident (LOCA) in nuclear reactors. An adsorption model as the precursory mechanism for rewetting of a superheated surface is extended from its application to non-polar liquids to a polar fluid, and modeling calculations are compared with experimental data found in the literature. The adsorption model is based on interfacial forces acting at the tip of the rewetting front, the three-phase region. In this region, solid, liquid and vapor interfaces generate a contact angle that depends on the degree of superheat and describes the velocity of rewetting. The contact angle is a function of interfacial forces calculated through the disjoining pressure of the adsorbed film precursory of the rewetting. The influences of van der Waals and electrostatic intermolecular forces in the film thickness are analyzed. The authors find that the order of magnitude of the film thickness in the controlling region is of a few angstroms: thus, only van der Waals intermolecular forces define the interactions. For the prediction of the velocity of rewetting the temperature profile along the rod's surface is required and a one-dimensional and a two-dimensional heat conduction balances are solved. The thermophysical properties in the adsorption model are predicted by ASPEN PLUS data bank and from ASME steam tables. Variations of the predicted values have a strong influence on the results. The surface boundary condition on the rod contains an evaporative heat transfer coefficient that is calculated from the fitted experimental rewetting velocities and the two-dimensional temperature field in the rod. Using this calculation scheme the values of the evaporative heat transfer coefficient are obtained in the normal range of values. Therefore the adsorption model gives results that are consistent with experimental observations.

  12. Correlated and uncorrelated invisible temporal white noise alters mesopic rod signaling.

    Science.gov (United States)

    Hathibelagal, Amithavikram R; Feigl, Beatrix; Kremers, Jan; Zele, Andrew J

    2016-03-01

    We determined how rod signaling at mesopic light levels is altered by extrinsic temporal white noise that is correlated or uncorrelated with the activity of one (magnocellular, parvocellular, or koniocellular) postreceptoral pathway. Rod and cone photoreceptor excitations were independently controlled using a four-primary photostimulator. Psychometric (Weibull) functions were measured for incremental rod pulses (50 to 250 ms) in the presence (or absence; control) of perceptually invisible subthreshold extrinsic noise. Uncorrelated (rod) noise facilitates rod detection. Correlated postreceptoral pathway noise produces differential changes in rod detection thresholds and decreases the slope of the psychometric functions. We demonstrate that invisible extrinsic noise changes rod-signaling characteristics within the three retinogeniculate pathways at mesopic illumination depending on the temporal profile of the rod stimulus and the extrinsic noise type.

  13. Sucker-rod pumping handbook production engineering fundamentals and long-stroke rod pumping

    CERN Document Server

    Takacs, Gabor

    2015-01-01

    Sucker-Rod Pumping Handbook presents the latest information on the most common form of production enhancement in today's oil industry, making up roughly two-thirds of the producing oilwell operations in the world. The book begins with an introduction to the main features of sucker rod pumping and an explanation and comparison of lift methods. It goes on to provide the technical and practical knowledge needed to introduce the new and practicing production engineer and operator to the equipment, technology, and applications required to maintain optimum operating conditions.

  14. Active and passive vibration isolation in piezoelectric phononic rods with external voltage excitation

    Directory of Open Access Journals (Sweden)

    Qicheng Zhang

    2017-05-01

    Full Text Available Active piezoelectric materials are applied to one-dimensional phononic crystals, for the control of longitudinal vibration propagation both in active and passive modes. Based on the electromechanical coupling between the acoustical vibration and electric field, the electromechanical equivalent method is taken to theoretically predict the transmission spectrum of the longitudinal vibration. It is shown that the phononic rod can suppress the vibration efficiently at the frequencies of interest, by actively optimizing the motions of piezoelectric elements. In an illustrated phononic rod of 11.2cm long, active tunable isolations of more than 20dB at low frequencies (500Hz-14kHz are generated by controlling the excitation voltages of piezoelectric elements. Meanwhile, passive fixed isolation at high frequencies (14k-63kHz are presented by its periodicity characteristics. Finite element simulations and vibration experiments on the rod demonstrate the effectiveness of the approach in terms of its vibration isolation capabilities and tunable characteristics. This phononic rod can be manufactured easily and provides numerous potential applications in designing isolation mounts and platforms.

  15. Optical, structural and morphological studies of (ZnO) nano-rod thin films for biosensor applications using sol gel technique

    Science.gov (United States)

    Wahab, H. A.; Salama, A. A.; El-Saeid, A. A.; Nur, O.; Willander, M.; Battisha, I. K.

    Uniformly distributed ZnO nano-rods (NRs) with diameters in nano-scale have been successfully grown in two stages; the first at annealing temperature (250-300 °C) for seed layer preparation on glass substrate by using sol gel technique and the second at low temperature (90-95 °C) by aqueous chemical growth (ACG) method. The same prepared thin film samples were grown on the surface of silver wire (0.25 mm in diameters) to produce electrochemical nano-sensors. The structure and the morphology of the prepared samples will be evaluated using XRD, Scanning electron microscope SEM. The absorption coefficient (α) and the band gap (Eg) for ZnO NRs thin films were determined. (α) was decreased by increasing the annealing temperature due to the increase of the surface roughness caused by higher temperature, where the creation of surface roughness gives rise to multi-reflections which, capture the reflected radiation and enhance the absorptivity. We are presenting an iron ion (Fe3+) potentiometric sensor based on functionalized ZnO nano-rods with selective iono-phore (18 crown 6). Zinc oxide nanorods (NRs) thin films with a diameter of about 68 up to 94 nm were grown on silver wire and gold coated glass.

  16. Synthesis of hierarchical TiO2 flower-rod and application in CdSe/CdS co-sensitized solar cell

    Science.gov (United States)

    Yu, Libo; Li, Zhen; Liu, Yingbo; Cheng, Fa; Sun, Shuqing

    2014-12-01

    A hierarchical double-layered TiO2 flower-rod structure composed of three-dimensional (3D) TiO2 flowers and one-dimensional (1D) nanorods on transparent fluorine-doped tin oxide (FTO) conducting glass has been synthesized by a facile hydrothermal method. The possible formation mechanism of the hierarchical architecture is also proposed. When used in CdSe/CdS quantum dots co-sensitized solar cells (QDSSCs), the 1D ordered rutile nanorods at bottom can accelerate the electron transfer rate by providing direct electrical pathway for photogenerated electrons, while the 3D flowers formed on the top of nanorods can increase the adsorption of QDs due to the enlarged areas, and can also be used as a scattering layer. The performance of the CdSe/CdS/TiO2 flower-rod solar cell can achieve a short-circuit current density (Jsc) of 13.46 mA cm-2, and a open-circuit voltage (Voc) of 0.42 V, with a maximum power conversion efficiency of 2.31% under one sun illumination (AM 1.5 G, 100 mW cm-2), which is greatly higher than that of CdSe/CdS/TiO2 nanorod solar cell (1.63%).

  17. On the application of electrochemical techniques for the preparation of {sup 57}Co source core, encapsulation and quality evaluation for radiometric assay of nuclear fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Dash, A.; Kumar, M.; Udhayakumar, J.; Gandhi, S.S.; Venkatesh, M. [Bhabha Atomic Reseach Center, Trombay, Mumbai (India). Radiopharmaceuticals Div.; Satpati, A.K. [Bhabha Atomic Reseach Center, Trombay, Mumbai (India). Analytical Chemistry Div.; Nuwad, J.; Shukla, R.; Pillai, C.G.S. [Bhabha Atomic Reseach Center, Trombay, Mumbai (India). Chemistry Div.; Venugopal, V. [Bhabha Atomic Reseach Center, Trombay, Mumbai (India). Radiochemistry and Isotope Group

    2011-07-01

    This paper describes an electrochemical method for the preparation of {sup 57}Co source to be used in quality evaluation of nuclear fuel rods. The electrolytic cell, the experimental set up used and the process of deposition are described. The effect of various parameters such as pH of the electrolyte, bath temperature, current density, content of cobalt in the bath, electrolyte volume in the cell and deposition time were investigated and optimized for maximum deposition. The texture and morphology of the electrodeposited samples were examined by X-ray diffraction (XRD), SEM and EDS analyses. Sources containing {proportional_to} 370 MBq (10 mCi) {sup 57}Co on a circular copper foil of 4 mm diameter could be prepared and encapsulated in an aluminum capsule. Quality assurance tests performed to ensure non-leachability, uniform distribution of activity and stability of the sources gave satisfactory results. (orig.)

  18. Application of the Integral Theory of Impact to the Qualification of Materials and the Development of a Simplified Rod Penetrator Model

    Science.gov (United States)

    1978-11-01

    material density ESTR normalized hydrodynamic mode energy, E of the layer, equal to .02505 x E* and E* has the units Btu/lbm THIK - the normalized line-of...one layer. P 7.86 g/cc CARD 5 DENS - P 7 - .462 p 17.0 gm/cc Btu 2/bec 2E, 200 1 t0/sft ESTR --- - x2.505x - - 5.01V+2 06 £2 31nib 10 ft Btu/ lbm sec...RODESCVCIVSI., ESTR ) - 7 HI5 3U $ROUTINE 14 THE ROD PRO1GRAM V COM’iUTES TML EFFECTIVE ESTAR OF THE RCOD C__-C0OMMON BMAXBIGMAELnVDESTbKEFREE,IHICKURHO,ESTP4T,CD

  19. On the Vortex Sound from Rotating Rods

    Science.gov (United States)

    Yudin, E. Y.

    1947-01-01

    The motion of different bodies imersed in liquid or gaseous media is accompanied by characteristic sound which is excited by the formation of unstable surfaces of separation behind the body, usually disintegrating into a system of discrete vortices(such as the Karman vortex street due to the flow about an infintely long rod, etc.).In the noise from fans,pumps,and similar machtnery, vortexnQif3eI?Yequently predominates. The purpose of this work is to elucidate certain questions of the dependence ofthis sound upon the aerodynamic parameters and the tip speed of the rotating rods,or blades. Although scme material is given below,insufficientto calculate the first rough approximation to the solution of this question,such as the mechanics of vortex formation,never the less certain conclusions maybe found of practical application for the reduction of noise from rotating blades.

  20. Evaluation of the reduction of boron-10 in the control rods in the BWR of the Laguna Verde Central, through steady state calculations; Evaluacion de la reduccion del Boro-10 en las barras de control en los BWR de la CLV, mediante calculos en estado estacionario

    Energy Technology Data Exchange (ETDEWEB)

    Montes T, J.L.; Perusquia, R.; Hernandez, J.L.; Ramirez S, J.R. [Departamento de Sistemas Nucleares, ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    One of the more important aspects related with the safety and economy in the operation of a nuclear power reactor, it is without a doubt the control of the reactivity. During the normal operation of a reactor of boiling water (BWR-Boiling Water Reactor), the control of the reactivity in the nucleus it is strongly determined by the efficiency of the control rods. In the case of the Laguna Verde Nuclear power station (CNLV) the nucleus of the reactors has 109 control rods grouped in 4 sets. The CNLV at the moment uses the CCC method (Control Cell Core) in the design of the cycle. With this method only the A2 group is used for the control of the reactivity at full power. With the purpose of quantifying the effect of the decrease of the burnable poison (B{sub 4}C) of the control rods and in particular to the effect due to the postulated lost of 10% of Boron 10, it was carried out a series of calculations of the nucleus in stationary state by means of the system of HELIOS/CM-PRESTO codes. In this work the main derived results of these 3D simulations(three dimensions) of the reactors of the CNLV are presented. It was analyzed the one behavior of the infinite neutron multiplication factor (K{sub infinite}), at fuel assemble cell level used in an equilibrium cycle for the CNLV. It was also analyzed the effect in the shutdown margin (ShutDown Margin- SDM) in cold condition CZP (Cold Zero Power). Its are also included those results of the ARI cases (All Rods In) and SRO (Strong Rod Out). From the cases in condition HFP (Hot Full Power) the behavior of the effective multiplication factor (K{sub eff}) is presented. (Author)

  1. ELECTROMAGNETIC APPARATUS FOR MOVING A ROD

    Science.gov (United States)

    Young, J.N.

    1957-08-20

    An electromagnetic device for moving an object in a linear path by increments is described. The device is specifically adapted for moving a neutron absorbing control rod into and out of the core of a reactor and consists essentially of an extension member made of magnetic material connected to one end of the control rod and mechanically flexible to grip the walls of a sleeve member when flexed, a magnetic sleeve member coaxial with and slidable between limit stops along the flexible extension, electromagnetic coils substantially centrally located with respect to the flexible extension to flex the extension member into gripping engagement with the sleeve member when ener gized, moving electromagnets at each end of the sleeve to attract the sleeve when energized, and a second gripping electromagnet positioned along the flexible extension at a distance from the previously mentioned electromagnets for gripping the extension member when energized. In use, the second gripping electromagnet is deenergized, the first gripping electromagnet is energized to fix the extension member in the sleeve, and one of the moving electromagnets is energized to attract the sleeve member toward it, thereby moving the control rod.

  2. Fasudil, a Clinically Used ROCK Inhibitor, Stabilizes Rod Photoreceptor Synapses after Retinal Detachment.

    Science.gov (United States)

    Townes-Anderson, Ellen; Wang, Jianfeng; Halász, Éva; Sugino, Ilene; Pitler, Amy; Whitehead, Ian; Zarbin, Marco

    2017-06-01

    Retinal detachment disrupts the rod-bipolar synapse in the outer plexiform layer by retraction of rod axons. We showed that breakage is due to RhoA activation whereas inhibition of Rho kinase (ROCK), using Y27632, reduces synaptic damage. We test whether the ROCK inhibitor fasudil, used for other clinical applications, can prevent synaptic injury after detachment. Detachments were made in pigs by subretinal injection of balanced salt solution (BSS) or fasudil (1, 10 mM). In some animals, fasudil was injected intravitreally after BSS-induced detachment. After 2 to 4 hours, retinae were fixed for immunocytochemistry and confocal microscopy. Axon retraction was quantified by imaging synaptic vesicle label in the outer nuclear layer. Apoptosis was analyzed using propidium iodide staining. For biochemical analysis by Western blotting, retinal explants, detached from retinal pigmented epithelium, were cultured for 2 hours. Subretinal injection of fasudil (10 mM) reduced retraction of rod spherules by 51.3% compared to control detachments ( n = 3 pigs, P = 0.002). Intravitreal injection of 10 mM fasudil, a more clinically feasible route of administration, also reduced retraction (28.7%, n = 5, P ROCK, was decreased with 30 μM fasudil ( n = 8-10 explants, P ROCK signaling with fasudil reduced photoreceptor degeneration and preserved the rod-bipolar synapse after retinal detachment. These results support the possibility, previously tested with Y27632, that ROCK inhibition may attenuate synaptic damage in iatrogenic detachments.

  3. A Novel Real-Time Path Servo Control of a Hardware-in-the-Loop for a Large-Stroke Asymmetric Rod-Less Pneumatic System under Variable Loads.

    Science.gov (United States)

    Lin, Hao-Ting

    2017-06-04

    This project aims to develop a novel large stroke asymmetric pneumatic servo system of a hardware-in-the-loop for path tracking control under variable loads based on the MATLAB Simulink real-time system. High pressure compressed air provided by the air compressor is utilized for the pneumatic proportional servo valve to drive the large stroke asymmetric rod-less pneumatic actuator. Due to the pressure differences between two chambers, the pneumatic actuator will operate. The highly nonlinear mathematical models of the large stroke asymmetric pneumatic system were analyzed and developed. The functional approximation technique based on the sliding mode controller (FASC) is developed as a controller to solve the uncertain time-varying nonlinear system. The MATLAB Simulink real-time system was a main control unit of a hardware-in-the-loop system proposed to establish driver blocks for analog and digital I/O, a linear encoder, a CPU and a large stroke asymmetric pneumatic rod-less system. By the position sensor, the position signals of the cylinder will be measured immediately. The measured signals will be viewed as the feedback signals of the pneumatic servo system for the study of real-time positioning control and path tracking control. Finally, real-time control of a large stroke asymmetric pneumatic servo system with measuring system, a large stroke asymmetric pneumatic servo system, data acquisition system and the control strategy software will be implemented. Thus, upgrading the high position precision and the trajectory tracking performance of the large stroke asymmetric pneumatic servo system will be realized to promote the high position precision and path tracking capability. Experimental results show that fifth order paths in various strokes and the sine wave path are successfully implemented in the test rig. Also, results of variable loads under the different angle were implemented experimentally.

  4. A Novel Real-Time Path Servo Control of a Hardware-in-the-Loop for a Large-Stroke Asymmetric Rod-Less Pneumatic System under Variable Loads

    Directory of Open Access Journals (Sweden)

    Hao-Ting Lin

    2017-06-01

    Full Text Available This project aims to develop a novel large stroke asymmetric pneumatic servo system of a hardware-in-the-loop for path tracking control under variable loads based on the MATLAB Simulink real-time system. High pressure compressed air provided by the air compressor is utilized for the pneumatic proportional servo valve to drive the large stroke asymmetric rod-less pneumatic actuator. Due to the pressure differences between two chambers, the pneumatic actuator will operate. The highly nonlinear mathematical models of the large stroke asymmetric pneumatic system were analyzed and developed. The functional approximation technique based on the sliding mode controller (FASC is developed as a controller to solve the uncertain time-varying nonlinear system. The MATLAB Simulink real-time system was a main control unit of a hardware-in-the-loop system proposed to establish driver blocks for analog and digital I/O, a linear encoder, a CPU and a large stroke asymmetric pneumatic rod-less system. By the position sensor, the position signals of the cylinder will be measured immediately. The measured signals will be viewed as the feedback signals of the pneumatic servo system for the study of real-time positioning control and path tracking control. Finally, real-time control of a large stroke asymmetric pneumatic servo system with measuring system, a large stroke asymmetric pneumatic servo system, data acquisition system and the control strategy software will be implemented. Thus, upgrading the high position precision and the trajectory tracking performance of the large stroke asymmetric pneumatic servo system will be realized to promote the high position precision and path tracking capability. Experimental results show that fifth order paths in various strokes and the sine wave path are successfully implemented in the test rig. Also, results of variable loads under the different angle were implemented experimentally.

  5. High-yield production of hydrophobins RodA and RodB from Aspergillus fumigatus in Pichia pastoris

    DEFF Research Database (Denmark)

    Pedersen, Mona Højgaard; Borodina, Irina; Moresco, Jacob Lange

    2011-01-01

    broth. Protein bands of expected sizes were detected by SDS-PAGE and western blotting, and the identity was further confirmed by tandem mass spectrometry. Both proteins were purified using his-affinity chromatography, and the high level of purity was verified by silver-stained SDS-PAGE. Recombinant Rod...... RodA showed a similar ability to emulsify air in water, while recombinant RodB could also emulsify oil in water better than the control protein bovine serum albumin (BSA). This is to our knowledge the first successful expression of hydrophobins from A. fumigatus in a eukaryote host, which makes...

  6. Comparison of different heuristic techniques for the optimization of control rod patterns; Comparacion de diferentes tecnicas heuristicas para la optimizacion del diseno de patrones de barras de control

    Energy Technology Data Exchange (ETDEWEB)

    Castillo M, J.A.; Ortiz S, J.J.; Perusquia C, R.; Montes T, J.L.; Hernandez M, J.L. [ININ, Carretera Mexico-Toluca s/n, 52750 La Marquesa, Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jacm@nuclear.inin.mx

    2007-07-01

    Presently work a comparison, using different methodologies, with the results obtained for the optimization of the design of control bar patterns for boiling water reactors is carried out. The results were obtained considering the same conditions for all the used methodologies, which are part of the combinatory optimization, these were programmed in FORTRAN 77 language under the UNIX platform in an ALPHA work station. The techniques used to carry out the optimization are the following ones, Genetic Algorithms, Dispersed Search, Taboo Search, Ants Colonies and Neural Networks. The objective function used is the same one in all the cases, in this its are included the MFLPD thermal limits (maximum fraction of power density to the end of the operation cycle), MPGR (Maxim rate of power generation at the end of the operation cycle) and MFLCPR (maximum fraction for the critical power ratio at the end of the operation cycle), of equal form it is included the criticality condition for the reactor and it is needed the Power Axial Profile in each step of burnt to be adjusted to a proposed Power Axial Profile. The CM-PRESTO code (Scandpower) was used to evaluate the proposed designs. The approach used for the comparison is essentially the k{sub eff} at the cycle end, as well as the thermal limits performance, nevertheless, it is also analyzed the exchanges number among the shallow and deep positions, and the total number of movements carried out during the complete cycle. (Author)

  7. Numerical simulation of the sucker-rod pumping system

    Directory of Open Access Journals (Sweden)

    Oldrich Joel Romero

    2014-11-01

    Full Text Available The sucker rod pump is an artificial lift method frequently applied in onshore petroleum wells. This system can be described using a numerical simulation based on the behavior of a rod string. In the past, the elastic behavior of the rod string made it difficult to model the system. However, since the 1960s and with the advent of digital computers, it has been modeled numerically. The rod string be-haves like a slender bar, and thus, the propagation of elastic waves along the bar can be represented by a one-dimensional equation. Gibbs (1963 presented a mathematical model based on the wave equation, which is described on the basis of the analysis of forces on the rod string and is incorporated into a boundary value problem involving partial differential equations. The use of the finite differ-ence method allows for a numerical solution by the discretization of the wave equation developed in the mathematical formulation with appropriate boundary and initial conditions. This work presents a methodology for implementing an academic computer code that allows simulation of the upstroke and downstroke motion of the rod string described by the wave equation under ideal operating conditions, assuming a harmonic motion of the rod at one end and downhole pump at the other end. The goal of this study is to generate the downhole dynamometer card, an important and consolidated tool that controls the pump system by diagnosing oper-ational conditions of the downhole pump.

  8. Application of Model Predictive Control to BESS for Microgrid Control

    Directory of Open Access Journals (Sweden)

    Thai-Thanh Nguyen

    2015-08-01

    Full Text Available Battery energy storage systems (BESSs have been widely used for microgrid control. Generally, BESS control systems are based on proportional-integral (PI control techniques with the outer and inner control loops based on PI regulators. Recently, model predictive control (MPC has attracted attention for application to future energy processing and control systems because it can easily deal with multivariable cases, system constraints, and nonlinearities. This study considers the application of MPC-based BESSs to microgrid control. Two types of MPC are presented in this study: MPC based on predictive power control (PPC and MPC based on PI control in the outer and predictive current control (PCC in the inner control loops. In particular, the effective application of MPC for microgrids with multiple BESSs should be considered because of the differences in their control performance. In this study, microgrids with two BESSs based on two MPC techniques are considered as an example. The control performance of the MPC used for the control microgrid is compared to that of the PI control. The proposed control strategy is investigated through simulations using MATLAB/Simulink software. The simulation results show that the response time, power and voltage ripples, and frequency spectrum could be improved significantly by using MPC.

  9. Composites reinforcement by rods a SAS study

    CERN Document Server

    Urban, V; Pyckhout-Hintzen, W; Richter, D; Straube, E

    2002-01-01

    The mechanical properties of composites are governed by size, shape and dispersion degree of so-called reinforcing particles. Polymeric fillers based on thermodynamically driven microphase separation of block copolymers offer the opportunity to study a model system of controlled rod-like filler particles. We chose a triblock copolymer (PBPSPB) and carried out SAS measurements with both X-rays and neutrons, in order to characterize separately the hard phase and the cross-linked PB matrix. The properties of the material depend strongly on the way that stress is carried and transferred between the soft matrix and the hard fibers. The failure of the strain-amplification concept and the change of topological contributions to the free energy and scattering factor have to be addressed. In this respect the composite shows a similarity to a two-network system, i.e. interpenetrating rubber and rod-like filler networks. (orig.)

  10. Sobre a técnica de Rod Drop em medidas de reatividade integral em bancos de controle e segurança de reatores

    OpenAIRE

    Giovanni Laranjo de Stefani

    2013-01-01

    Este trabalho apresenta um estudo sobre o efeito de sombreamento em detectores de nêutrons, quando estes são utilizados em medidas de reatividade com a técnica de rod drop. O sombreamento pode ser entendido como uma mudança na eciência dos detectores, quando esta é dada em nêutrons detectados/ssão ocorrida no reator, sendo mais evidente nos detectores mais próximos ao banco sendo inserido. O método de análise, fundamentalmente teórica, baseou-se em simulações do reator IPEN/MB-01 utilizando o...

  11. Advances and applications in nonlinear control systems

    CERN Document Server

    Volos, Christos

    2016-01-01

    The book reports on the latest advances and applications of nonlinear control systems. It consists of 30 contributed chapters by subject experts who are specialized in the various topics addressed in this book. The special chapters have been brought out in the broad areas of nonlinear control systems such as robotics, nonlinear circuits, power systems, memristors, underwater vehicles, chemical processes, observer design, output regulation, backstepping control, sliding mode control, time-delayed control, variables structure control, robust adaptive control, fuzzy logic control, chaos, hyperchaos, jerk systems, hyperjerk systems, chaos control, chaos synchronization, etc. Special importance was given to chapters offering practical solutions, modeling and novel control methods for the recent research problems in nonlinear control systems. This book will serve as a reference book for graduate students and researchers with a basic knowledge of electrical and control systems engineering. The resulting design proce...

  12. Motion simulation of hydraulic driven safety rod using FSI method

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jaeho; Kim, Sanghaun; Yoo, Yeonsik; Cho, Yeonggarp; Kim, Jong In [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    Hydraulic driven safety rod which is one of them is being developed by Division for Reactor Mechanical Engineering, KAERI. In this paper the motion of this rod is simulated by fluid structure interaction (FSI) method before manufacturing for design verification and pump sizing. A newly designed hydraulic driven safety rod which is one of reactivity control mechanism is simulated using FSI method for design verification and pump sizing. The simulation is done in CFD domain with UDF. The pressure drop is changed slightly by flow rates. It means that the pressure drop is mainly determined by weight of moving part. The simulated velocity of piston is linearly proportional to flow rates so the pump can be sized easily according to the rising and drop time requirement of the safety rod using the simulation results.

  13. The Third ATLAS ROD Workshop

    CERN Multimedia

    Poggioli, L.

    A new-style Workshop After two successful ATLAS ROD Workshops dedicated to the ROD hardware and held at the Geneva University in 1998 and in 2000, a new style Workshop took place at LAPP in Annecy on November 14-15, 2002. This time the Workshop was fully dedicated to the ROD-TDAQ integration and software in view of the near future integration activities of the final RODs for the detector assembly and commissioning. More precisely, the aim of this workshop was to get from the sub-detectors the parameters needed for T-DAQ, as well as status and plans from ROD builders. On the other hand, what was decided and assumed had to be stated (like EB decisions and URDs), and also support plans. The Workshop gathered about 70 participants from all ATLAS sub-detectors and the T-DAQ community. The quite dense agenda allowed nevertheless for many lively discussions, and for a dinner in the old town of Annecy. The Sessions The Workshop was organized in five main sessions: Assumptions and recommendations Sub-de...

  14. Modular Multilevel Converters: Control and Applications

    Directory of Open Access Journals (Sweden)

    Fernando Martinez-Rodrigo

    2017-10-01

    Full Text Available This review article is mainly oriented to the control and applications of modular multilevel converters (MMC. The main topologies of the switching modules are presented, for normal operation and for the elimination of DC faults. Methods to keep the capacitor voltage balanced are included. The voltage and current modulators, that are the most internal loops of control, are detailed. Voltage control and current control schemes are included which regulate DC link voltage and reactive power. The cases of unbalanced and distorted networks are analyzed, and schemes are proposed so that MMC contribute to improve the quality of the grid in these situations. The main applications in high voltage direct current (HVDC transmission along with other medium voltage (MV and low voltage (LV applications are included. Finally, the application to offshore wind farms is specifically analyzed.

  15. Design, modeling and optimization of poly-air gap actuators with global coils: application to multi-rod linear structures; Conception, modelisation et optimisation des actionneurs polyentrefers a bobinages globaux: application aux structures lineaires multi-tiges

    Energy Technology Data Exchange (ETDEWEB)

    Cavarec, P.E.

    2002-11-15

    The aim of this thesis is the study and the conception of splitted structures of global coil synchronous machines for the maximization of specific torque or thrust. This concept of machine, called multi-air gap, is more precisely applied to the elaboration of a new linear multi-rods actuator. It is clearly connected to the context of direct drive solutions. First, a classification of different electromagnetic actuator families gives the particular place of multi-air gaps actuators. Then, a study, based on geometrical parameters optimizations, underlines the interest of that kind of topology for reaching very high specific forces and mechanical dynamics. A similitude law, governing those actuators, is then extracted. A study of mechanical behaviour, taking into account mechanic (tolerance) and normal forces (guidance), is carried out. Hence, methods for filtering the ripple force, and decreasing the parasitic forces without affecting the useful force are presented. This approach drives to the multi-rods structures. A prototype is then tested and validates the feasibility of that kind of devices, and the accuracy of the magnetic models. This motor, having only eight rods for an active volume of one litre, reaches an electromagnetic force of 1000 N in static conditions. A method for estimate optimal performances of multi-rods actuators under several mechanical stresses is presented. (author)

  16. Optimal control with aerospace applications

    CERN Document Server

    Longuski, James M; Prussing, John E

    2014-01-01

    Want to know not just what makes rockets go up but how to do it optimally? Optimal control theory has become such an important field in aerospace engineering that no graduate student or practicing engineer can afford to be without a working knowledge of it. This is the first book that begins from scratch to teach the reader the basic principles of the calculus of variations, develop the necessary conditions step-by-step, and introduce the elementary computational techniques of optimal control. This book, with problems and an online solution manual, provides the graduate-level reader with enough introductory knowledge so that he or she can not only read the literature and study the next level textbook but can also apply the theory to find optimal solutions in practice. No more is needed than the usual background of an undergraduate engineering, science, or mathematics program: namely calculus, differential equations, and numerical integration. Although finding optimal solutions for these problems is a...

  17. Polypeptide-b-Poly(Phenyl Isocyanide) Hybrid Rod-Rod Copolymers: One-Pot Synthesis, Self-Assembly, and Cell Imaging.

    Science.gov (United States)

    Shi, Sheng-Yu; He, Ya-Guang; Chen, Wei-Wei; Liu, Na; Zhu, Yuan-Yuan; Ding, Yun-Sheng; Yin, Jun; Wu, Zong-Quan

    2015-08-01

    Hybrid rod-rod diblock copolymers, poly(γ-benzyl L-glutamate)-poly(4-cyano-benzoic acid 2-isopropyl-5-methyl-cyclohexyl ester) (PBLG-PPI), with determined chirality are facilely synthesized through sequential copolymerization of γ-benzyl-L-glutamate N-carboxyanhydride (BLG-NCA) and phenyl isocyanide monomers bearing chiral menthyl pendants using a Ni(cod)(bpy) complex as the catalyst in one-pot. Circular dichroism and absorption spectra reveal that each block of the block copolymers possesses a stable helical conformation with controlled helicity in solution due to the induction of chiral pendants. The two diastereomeric polymers self-assemble into helical nanofibrils with opposite handedness due to the different chiral induction of the L- and D-menthyl pendants, confirmed by transmission electron microscopy (TEM). Deprotection of the benzyl groups of the PBLG segment affords biocompatible amphiphilic diblock copolymers, poly(L-glutamic acid)-poly(4-cyano-benzoic acid 2-isopropyl-5-methyl-cyclohexyl ester) (PLGA-PPI), that can self-assemble into well-defined micelles by cosolvent induced aggregation. Very interestingly, a chiral rhodamine chromophores RhB(D) can be selectively encapsulated into the chiral polymeric micelles, which is efficiently internalized into living cells when directly monitored with a confocal microscope. This contribution will be useful for developing novel rod-rod biocompatible hybrid block copolymers with a controlled helicity, and may also provide unique chiral materials for potential bio-medical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Inhibition of Matrix Metalloproteinase 9 Enhances Rod Survival in the S334ter-line3 Retinitis Pigmentosa Model.

    Directory of Open Access Journals (Sweden)

    Jung-A Shin

    Full Text Available Retinitis Pigmentosa (RP is one of the most common forms of inherited visual loss with the initial degeneration of rod photoreceptors, followed by a progressive cone photoreceptor deterioration. Coinciding with this visual loss, the extracellular matrix (ECM is reorganized, which alters matrix metalloproteinase (MMP activity levels. A potential pathological role of MMPs, MMP-9 in particular, involves an excitotoxicity-mediated physiological response. In the current study, we examine the MMP-9 and MMP-2 expression levels in the rhodopsin S334ter-line3 RP rat model and investigate the impact of treatment with SB-3CT, a specific MMP-9 and MMP-2 inhibitor, on rod cell survival was tested. Retinal MMP-9 and MMP-2 expression levels were quantified by immunoblot analysis from S334ter-line3 rats compared to controls. Gelatinolytic activities of MMP-9 and MMP-2 by zymography were examined. The geometry of rod death was further evaluated using Voronoi analysis. Our results revealed that MMP-9 was elevated while MMP-2 was relatively unchanged when S334ter-line 3 retinas were compared to controls. With SB-3CT treatment, we observed gelatinolytic activity of both MMPs was decreased and diminished clustering associated with rod death, in addition to a robust preservation of rod photoreceptors. These results demonstrate that up-regulation of MMP-9 in retinas of S334ter-line3 are associated with rod death. The application of SB-3CT dramatically interferes with mechanisms leading to apoptosis in an MMP-9-dependent manner. Future studies will determine the feasibility of using SB-3CT as a potential therapeutic strategy to slow progression of vision loss in genetic inherited forms of human RP.

  19. Results of Post Irradiation Examinations of VVER Leaky Rods

    Energy Technology Data Exchange (ETDEWEB)

    Markov, D.; Perepelkin, S.; Polenok, V.; Zhitelev, V.; Mayorshina, G. [Head of Fuel Research Department, JSC ' SSC RIAR' , 433510, Dimitrovgrad-10, Ulyanovsk region (Russian Federation)

    2009-06-15

    The most important requirement imposed on fuel elements is to maintain integrity of fuel rod claddings under operation, storage and transportation, since it is directly related to the operational safety. However, failed rod claddings are sometimes observed under reactor operation. Identification and unloading of fuel assemblies with leaky rods from VVER is available only at the time of planned preventive maintenance. An unscheduled reactor shutdown due to the excess of coolant activity limit as well as a preterm unloading of the fuel assembly cause economic damage to nuclear plant. Therefore, models and calculation codes were developed to forecast coolant contamination and failed fuel rod behavior. Criteria based on calculations were set to determine the admissible number of the failed rods in core and the opportunity to continue the reactor operation or pre-term unloading of the fuel assembly with the failed rods. Nevertheless, to prevent the fuel rod failure (for unfailing operation) it is necessary to reveal disadvantages of the design, fabrication method and fuel operation conditions, and to eliminate defects. The most complete and significant information about spent fuel assemblies may be received following the post irradiation material examinations. In order to reveal failure origins and mechanism of changes in VVER fuel and failed rod cladding condition depending on the operation, the examinations of 12 VVER-1000 fuel assemblies and 3 VVER-440 fuel assemblies, operated under normal conditions up to the fuel burnup 13..47 MWd/kgU were carried out. To evaluate the rod cladding condition, reveal defects and determine their parameters, the ultrasonic control of cladding integrity, surface visual inspection, eddy current defectoscopy, measurement of geometrical parameters were applied. In separate cases we used the metallography, measured the hydrogen percentage and carried out the mechanical tests of o-ring samples. The pellet condition was evaluated in

  20. Performance of the NRX shut-off rods

    Energy Technology Data Exchange (ETDEWEB)

    Manson, R.E.

    1965-08-15

    A new type of shut-off rod of electromechanical design was developed by the American Machine and Foundry Company for use in the NRX reactor following the accident of 1952. The new rods were installed in May, 1956, as part of the control system conversion program which was completed in 1958. Some problems were encountered with limit switch adjustment but minor modifications in design led to much improved operation. he performance of the rods also improved as more experience was gained in the maintenance and adjustment of the various headgear components. Each headgear is now overhauled once a year on a routine basis. The present design of shut-off rod is considered to be very satisfactory. There has only been one occasion when a shut-off rod has failed to come fully down on a trip. Rods have failed to operate correctly on five other occasions but these occurred during shutdown periods or when the reactor was being shutdown manually. (author)

  1. Vibrational Power Flow Analysis of Rods and Beams

    Science.gov (United States)

    Wohlever, James Christopher; Bernhard, R. J.

    1988-01-01

    A new method to model vibrational power flow and predict the resulting energy density levels in uniform rods and beams is investigated. This method models the flow of vibrational power in a manner analogous to the flow of thermal power in a heat conduction problem. The classical displacement solutions for harmonically excited, hysteretically damped rods and beams are used to derive expressions for the vibrational power flow and energy density in the rod and beam. Under certain conditions, the power flow in these two structural elements will be shown to be proportional to the energy density gradient. Using the relationship between power flow and energy density, an energy balance on differential control volumes in the rod and beam leads to a Poisson's equation which models the energy density distribution in the rod and beam. Coupling the energy density and power flow solutions for rods and beams is also discussed. It is shown that the resonant behavior of finite structures complicates the coupling of solutions, especially when the excitations are single frequency inputs. Two coupling formulations are discussed, the first based on the receptance method, and the second on the travelling wave approach used in Statistical Energy Analysis. The receptance method is the more computationally intensive but is capable of analyzing single frequency excitation cases. The traveling wave approach gives a good approximation of the frequency average of energy density and power flow in coupled systems, and thus, is an efficient technique for use with broadband frequency excitation.

  2. Unfalsified Control; Application to automatic flight control system design

    Directory of Open Access Journals (Sweden)

    Adrian-Mihail STOICA

    2011-09-01

    Full Text Available Unfalsified Control Theory has been developed to provide a way for avoiding modeling uncertainties in controller design. It belongs to the class of control methods called Adaptive Supervisory Switching Control, which work by introducing in the control scheme a supervisory unit which chooses, from a set of candidate controllers the one most suited for the current plant. Unfalsified Control works by using a switching logic that dispenses with the need for a-priori knowledge of the dynamic model. At discrete moments of time, using the input/output data recorded up to that point, the supervisory calculates for each candidate controller a performance index, and compares it to a given threshold. Controllers surpassing that threshold are removed from the candidate controller set. This process is called falsification. If the controller in the loop is one such falsified controller it is replaced. In this paper we investigate the suitability of this method for aeronautical control applications. We review the theory behind this control scheme and adapt it to the case of controlling a fighter aircraft. We also provide a case study, where we test this control scheme on a simulated fighter aircraft.

  3. Decentralized neural control application to robotics

    CERN Document Server

    Garcia-Hernandez, Ramon; Sanchez, Edgar N; Alanis, Alma y; Ruz-Hernandez, Jose A

    2017-01-01

    This book provides a decentralized approach for the identification and control of robotics systems. It also presents recent research in decentralized neural control and includes applications to robotics. Decentralized control is free from difficulties due to complexity in design, debugging, data gathering and storage requirements, making it preferable for interconnected systems. Furthermore, as opposed to the centralized approach, it can be implemented with parallel processors. This approach deals with four decentralized control schemes, which are able to identify the robot dynamics. The training of each neural network is performed on-line using an extended Kalman filter (EKF). The first indirect decentralized control scheme applies the discrete-time block control approach, to formulate a nonlinear sliding manifold. The second direct decentralized neural control scheme is based on the backstepping technique, approximated by a high order neural network. The third control scheme applies a decentralized neural i...

  4. Touchless application control with Kinect sensor

    OpenAIRE

    Černivec, Andrej

    2014-01-01

    The aim of the thesis was to develop an application that would allow us to control any application on Windows operating system using a motion capture sensor. Sensor used for motion capture was Microsoft Kinect. Programing language used for developing was C#, the framework used was Microsoft .NET and the library used to communicate with the Kinect sensor was Kinect for Windows SDK. Libraries Coding4fun Kinect Toolkit and InputSimulator were used for the implementation of some additional functi...

  5. Application of artificial intelligence in process control

    CERN Document Server

    Krijgsman, A

    1993-01-01

    This book is the result of a united effort of six European universities to create an overall course on the appplication of artificial intelligence (AI) in process control. The book includes an introduction to key areas including; knowledge representation, expert, logic, fuzzy logic, neural network, and object oriented-based approaches in AI. Part two covers the application to control engineering, part three: Real-Time Issues, part four: CAD Systems and Expert Systems, part five: Intelligent Control and part six: Supervisory Control, Monitoring and Optimization.

  6. Method of targeted delivery of laser beam to isolated retinal rods by fiber optics.

    Science.gov (United States)

    Sim, Nigel; Bessarab, Dmitri; Jones, C Michael; Krivitsky, Leonid

    2011-11-01

    A method of controllable light delivery to retinal rod cells using an optical fiber is described. Photo-induced current of the living rod cells was measured with the suction electrode technique. The approach was tested with measurements relating the spatial distribution of the light intensity to photo-induced current. In addition, the ion current responses of rod cells to polarized light at two different orientation geometries of the cells were studied.

  7. Modular control system for embedded applications

    Directory of Open Access Journals (Sweden)

    Dostálek Petr

    2016-01-01

    Full Text Available This paper deals with hardware design of a modular control system intended for embedded applications demanding high computational power while maintaining low cost. The control system central unit is based on 32bit microcontroller MK60DN512 with ARM Cortex-M4 core manufactured by NXP Semiconductor. Module provides all the necessary signals on the two 2-row 40 pin headers and Ethernet communication interface in the form of a small daughter board. It is connected to the mainboard which must always contain 5 V stabilized power supply; other circuits are application specific. In our application the mainboard is equipped with SD card slot, RS232 and RS485 interface which is used for high speed interconnection with up to 15 expansion peripheral modules. This concept enables high flexibility to specific application demands without necessity of redesigning the control system. Controller is freely programmable in C language using any compatible integrated development environment – NXP Kinetis Design Studio, for example. Software development and debugging is simplified by our support program libraries including necessary routines for control and monitoring tasks.

  8. Fuzzy modeling and control theory and applications

    CERN Document Server

    Matía, Fernando; Jiménez, Emilio

    2014-01-01

    Much work on fuzzy control, covering research, development and applications, has been developed in Europe since the 90's. Nevertheless, the existing books in the field are compilations of articles without interconnection or logical structure or they express the personal point of view of the author. This book compiles the developments of researchers with demonstrated experience in the field of fuzzy control following a logic structure and a unified the style. The first chapters of the book are dedicated to the introduction of the main fuzzy logic techniques, where the following chapters focus on concrete applications. This book is supported by the EUSFLAT and CEA-IFAC societies, which include a large number of researchers in the field of fuzzy logic and control. The central topic of the book, Fuzzy Control, is one of the main research and development lines covered by these associations.

  9. Rod and lamellar growth of eutectic

    Directory of Open Access Journals (Sweden)

    M. Trepczyńska-Łent

    2010-04-01

    Full Text Available The paper presents adaptation problem of lamellar growth of eutectic. The formation of rod eutectic microstructure was investigated systematically. A new rod eutectic configuration was observed in which the rods form with elliptical cylindrical shape. A new interpretation of the eutectic growth theory was proposed.

  10. Solitary waves on nonlinear elastic rods. II

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.

    1987-01-01

    In continuation of an earlier study of propagation of solitary waves on nonlinear elastic rods, numerical investigations of blowup, reflection, and fission at continuous and discontinuous variation of the cross section for the rod and reflection at the end of the rod are presented. The results...

  11. Modeling of primary water stress corrosion cracking at control rod drive mechanism nozzles of pressurized water reactors; Modelagem da fratura por corrosao sob tensao nos bocais do mecanismo de acionamento das barras de controle de reator de agua pressurizada

    Energy Technology Data Exchange (ETDEWEB)

    Aly, Omar Fernandes

    2006-07-01

    One of the main failure mechanisms that cause risks to pressurized water reactors is the primary water stress corrosion cracking (PWSCC) occurring in alloys. It can occurs, besides another places, at the control reactor displacement mechanism nozzles. It is caused by the joint effect of tensile stress, temperature, susceptible metallurgical microstructure and environmental conditions of the primary water. These cracks can cause accidents that reduce nuclear safety by blocking the rod's displacement and may cause leakage of primary water, reducing the reactor's life. In this work it is proposed a study of the existing models and a modeling proposal to primary water stress corrosion cracking in these nozzles in a nickel based Alloy 600. It is been superposed electrochemical and fracture mechanics models, and validated using experimental and literature data. The experimental data were obtained at CDTN-Brazilian Nuclear Technology Development Center, in a recent installed slow strain rate testing equipment. In the literature it is found a diagram that indicates a thermodynamic condition for the occurrence of some PWSCC sub modes in Alloy 600: it was used potential x pH diagrams (Pourbaix diagrams), for Alloy 600 in high temperature primary water (300 deg C till 350 deg C). Over it, were located the PWSCC sub modes, using experimental data. It was added a third parameter called 'stress corrosion strength fraction'. However, it is possible to superpose to this diagram, other parameters expressing PWSCC initiation or growth kinetics from other models. Here is the proposition of the original contribution of this work: from an original experimental condition of potential versus pH, it was superposed, an empiric-comparative, a semi-empiric-probabilistic, an initiation time, and a strain rate damage models, to quantify respectively the PWSCC susceptibility, the failure time, and in the two lasts, the initiation time of stress corrosion cracking. It was

  12. Hemispherical-rod microlens as a variant fractional Fourier transformer.

    Science.gov (United States)

    Dragoman, D; Brenner, K H; Dragoman, M; Bähr, J; Krackhardt, U

    1998-10-01

    It is shown that a hemispherical-rod microlens can act as a fractional Fourier transform device with a continuously varying degree of fractionality. It is believed to be the first proposed device to perform such a task; its most immediate applications include optical tomography.

  13. Exploiting rod technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-06-01

    ROD development was proceeding apace until recent budgetary decisions caused funding support for ROD development to be drastically reduced. The funding which was originally provided by DARPA and the Balanced Technology Initiative (BTI) Office has been cut back to zero from $800K. To determine the aeroballistic coefficients of a candidate dart, ARDEC is currently supporting development out of its own 6.2 funds at about $100K. ARDEC has made slow progress toward achieving this end because of failures in the original dart during testing. It appears that the next dart design to be tested will diverge from the original concept visualized by DARPA and Science and Technology Associates (STA). STA, the design engineer, takes exception to these changes on the basis of inappropriate test conditions and insufficient testing. At this time, the full resolution of this issue will be difficult because of the current management structure, which separates the developer (ARDEC) from the designer (STA).

  14. Stimuli responsive nanomaterials for controlled release applications

    KAUST Repository

    Li, Song

    2012-01-01

    The controlled release of therapeutics has been one of the major challenges for scientists and engineers during the past three decades. Coupled with excellent biocompatibility profiles, various nanomaterials have showed great promise for biomedical applications. Stimuli-responsive nanomaterials guarantee the controlled release of cargo to a given location, at a specific time, and with an accurate amount. In this review, we have combined the major stimuli that are currently used to achieve the ultimate goal of controlled and targeted release by "smart" nanomaterials. The most heavily explored strategies include (1) pH, (2) enzymes, (3) redox, (4) magnetic, and (5) light-triggered release.

  15. Modular control of fusion power heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Demers, D. R.

    2012-08-24

    This work is motivated by the growing demand for auxiliary heating on small and large machines worldwide. Numerous present and planned RF experiments (EBW, Lower Hybrid, ICRF, and ECH) are increasingly complex systems. The operational challenges are indicative of a need for components of real-time control that can be implemented with a moderate amount of effort in a time- and cost-effective fashion. Such a system will improve experimental efficiency, enhance experimental quality, and expedite technological advancements. The modular architecture of this control-suite serves multiple purposes. It facilitates construction on various scales from single to multiple controller systems. It enables expandability of control from basic to complex via the addition of modules with varying functionalities. It simplifies the control implementation process by reducing layers of software and electronic development. While conceived with fusion applications in mind, this suite has the potential to serve a broad range of scientific and industrial applications. During the Phase-I research effort we established the overall feasibility of this modular control-suite concept. We developed the fundamental modules needed to implement open-loop active-control and demonstrated their use on a microwave power deposition experiment.

  16. Optimal control applications in electric power systems

    CERN Document Server

    Christensen, G S; Soliman, S A

    1987-01-01

    Significant advances in the field of optimal control have been made over the past few decades. These advances have been well documented in numerous fine publications, and have motivated a number of innovations in electric power system engineering, but they have not yet been collected in book form. Our purpose in writing this book is to provide a description of some of the applications of optimal control techniques to practical power system problems. The book is designed for advanced undergraduate courses in electric power systems, as well as graduate courses in electrical engineering, applied mathematics, and industrial engineering. It is also intended as a self-study aid for practicing personnel involved in the planning and operation of electric power systems for utilities, manufacturers, and consulting and government regulatory agencies. The book consists of seven chapters. It begins with an introductory chapter that briefly reviews the history of optimal control and its power system applications and also p...

  17. Steam by-pass reciprocating rod pump

    Energy Technology Data Exchange (ETDEWEB)

    Waterhouse, B. [Weatherford, Edmonton, AB (Canada)

    2008-07-01

    This article presented the design details of Weatherford's steam by-pass reciprocating rod rod pump which was designed to work under specific well conditions and individual applications, including Imperial Oil's Cold Lake bitumen recovery project located 230 km northeast of Edmonton, Alberta. Imperial Oil uses a cyclic steam stimulation (CSS) process to enhance bitumen recovery from the Clearwater oil sand reservoir. A typical wellbore reach can be up to 700 m and 80 degrees deviation at a target depth of 455 m TVD. These long well bore reaches along with high bottomhole angles and high produced fluid viscosities complicate the design of the artificial lift, which is essentially a modified conventional API pump. The hold-down section is a friction ring design incorporating stainless steel friction rings to provide positive holding force. The steam by-pass coupling is a reduced-diameter tube fitting between the API pump and the friction ring hold-down section. Three stages of the Imperial Cold Lake operation were described, namely the steam injection stage, soak phase stage and production stage. Typically, the steam by-pass pump is suspended in the tubing for the entire cycle. This presentation reviewed the operating steps of the pump, whose average run time in the field is about 15 months, depending on the potential for scaling or sand influx. tab., figs.

  18. Access control administration in healthcare applications.

    Science.gov (United States)

    Andreas, Mattas K; Ioannis, Mavridis K; George, Pangalos I

    2002-01-01

    The interconnection of information systems of different parties involved in healthcare applications leads to the need for information sharing across large-scale and highly distributed database systems. Applying appropriate access control policies in an effective and flexible way is a specific task for a number of local security officers that must operate according to a high-level access control administration system. The particular security requirements of healthcare information systems are reflected to the access control system, which must be flexible and dynamically adaptable to the daily activities. Decentralizing access control administration can be achieved in a uniform and consistent way when applying appropriate administrative rules and constraints. In this paper are presented the basic features of an access control administration model for interconnected information systems, as in the healthcare environment.

  19. Fuel rod assembly to manifold attachment

    Science.gov (United States)

    Donck, Harry A.; Veca, Anthony R.; Snyder, Jr., Harold J.

    1980-01-01

    A fuel element is formed with a plurality of fuel rod assemblies detachably connected to an overhead support with each of the fuel rod assemblies having a gas tight seal with the support to allow internal fission gaseous products to flow without leakage from the fuel rod assemblies into a vent manifold passageway system on the support. The upper ends of the fuel rod assemblies are located at vertically extending openings in the support and upper threaded members are threaded to the fuel rod assemblies to connect the latter to the support. The preferred threaded members are cap nuts having a dome wall encircling an upper threaded end on the fuel rod assembly and having an upper sealing surface for sealing contact with the support. Another and lower seal is achieved by abutting a sealing surface on each fuel rod assembly with the support. A deformable portion on the cap nut locks the latter against inadvertent turning off the fuel rod assembly. Orienting means on the fuel rod and support primarily locates the fuel rods azimuthally for reception of a deforming tool for the cap nut. A cross port in the fuel rod end plug discharges into a sealed annulus within the support, which serves as a circumferential chamber, connecting the manifold gas passageways in the support.

  20. iRODS: A Distributed Data Management Cyberinfrastructure for Observatories

    Science.gov (United States)

    Rajasekar, A.; Moore, R.; Vernon, F.

    2007-12-01

    Rule-Oriented Data System (iRODS) (http://irods.sdsc.edu) provides the mechanisms needed to describe not only management policies, but also to track how the policies are applied and their execution results. The iRODS data grid maps management policies to rules that control the execution of the remote micro-services. As an example, a rule can be created that automatically creates a replica whenever a file is added to a specific collection, or extracts its metadata automatically and registers it in a searchable catalog. For the replication operation, the persistent state information consists of the replica location, the creation date, the owner, the replica size, etc. The mechanism used by iRODS for providing policy virtualization is based on well-defined functions, called micro-services, which are chained into alternative workflows using rules. A rule engine, based on the event-condition-action paradigm executes the rule-based workflows after an event. Rules can be deferred to a pre-determined time or executed on a periodic basis. As the data management policies evolve, the iRODS system can implement new rules, new micro-services, and new state information (metadata content) needed to manage the new policies. Each sub- collection can be managed using a different set of policies. The discussion of the concepts in rule-based policy virtualization and its application to long-term and large-scale data management for observatories such as ORION and NEON will be the basis of the paper.

  1. Reinventing User Applications for Mission Control

    Science.gov (United States)

    Trimble, Jay Phillip; Crocker, Alan R.

    2010-01-01

    In 2006, NASA Ames Research Center's (ARC) Intelligent Systems Division, and NASA Johnson Space Centers (JSC) Mission Operations Directorate (MOD) began a collaboration to move user applications for JSC's mission control center to a new software architecture, intended to replace the existing user applications being used for the Space Shuttle and the International Space Station. It must also carry NASA/JSC mission operations forward to the future, meeting the needs for NASA's exploration programs beyond low Earth orbit. Key requirements for the new architecture, called Mission Control Technologies (MCT) are that end users must be able to compose and build their own software displays without the need for programming, or direct support and approval from a platform services organization. Developers must be able to build MCT components using industry standard languages and tools. Each component of MCT must be interoperable with other components, regardless of what organization develops them. For platform service providers and MOD management, MCT must be cost effective, maintainable and evolvable. MCT software is built from components that are presented to users as composable user objects. A user object is an entity that represents a domain object such as a telemetry point, a command, a timeline, an activity, or a step in a procedure. User objects may be composed and reused, for example a telemetry point may be used in a traditional monitoring display, and that same telemetry user object may be composed into a procedure step. In either display, that same telemetry point may be shown in different views, such as a plot, an alpha numeric, or a meta-data view and those views may be changed live and in place. MCT presents users with a single unified user environment that contains all the objects required to perform applicable flight controller tasks, thus users do not have to use multiple applications, the traditional boundaries that exist between multiple heterogeneous

  2. Process Management Development for Quality Monitoring on Resistance Weldment of Nuclear Fuel Rods

    Energy Technology Data Exchange (ETDEWEB)

    Na, Tae Hyung; Yang, Kyung Hwan; Kim, In Kyu [KEPCO, Daejeon (Korea, Republic of)

    2016-05-15

    The current, welding force, and displacement are displayed on the indicator during welding. However, real-time quality control is not performed. Due to the importance of fuel rod weldment, many studies on welding procedures have been conducted. However, there are not enough studies regarding weldment quality evaluation. On the other hand, there are continuous studies on the monitoring and control of welding phenomena. In resistance welding, which is performed in a very short time, it is important to find the process parameters that well represent the weld zone formation and the welding process. In his study, Gould attempted to analyze melt zone formation using the finite difference method. Using the artificial neural network, Javed and Sanders, Messler Jr et al., Cho and Rhee, Li and Gong et al. estimated the size of the melt zone by mapping a nonlinear functional relation between the weldment and the electrode head movement, which is a typical welding process parameter. Applications of the artificial intelligence method include fuzzy control using electrode displacement, fuzzy control using the optimal power curve, neural network control using the dynamic resistance curve, fuzzy adaptive control using the optimal electrode curve, etc. Therefore, this study induced quality factors for the real-time quality control of nuclear fuel rod end plug weldment using instantaneous dynamic resistance (IDR), which incorporates the instantaneous value of secondary current and voltage of the transformer, and using instantaneous dynamic force (IDF), obtained real-time during welding.

  3. Development of CCD controller for scientific application

    Science.gov (United States)

    Khan, M. S.; Pathan, F. M.; Shah, U. V., Prof; Makwana, D. H., Prof; Anandarao, B. G., Prof

    2010-02-01

    Photoelectric equipment has wide applications such as spectroscopy, temperature measurement in infrared region and in astronomical research etc. A photoelectric transducer converts radiant energy into electrical energy. There are two types of photoelectric transducers namely photo-multiplier tube (PMT) and charged couple device (CCD) are used to convert radiant energy into electrical signal. Now the entire modern instruments use CCD technology. We have designed and developed a CCD camera controller using camera chip CD47-10 of Marconi which has 1K × 1K pixel for space application only.

  4. Nonlinear stiffness profiles of external fixators constructed with composite rods.

    Science.gov (United States)

    Carlson, Kimberly R; Kraus, Karl H; Kowaleski, Michael P

    2006-12-01

    To determine if composite connecting rods confer nonlinear stiffness characteristics on unilateral and bilateral external skeletal fixators (ESF) in cranial-caudal bending and axial loading. Mechanical testing performed on models. Six models of 6-pin ESF constructs composed of birch dowels, a commercial ESF system, and composite connecting rods. Unilateral and bilateral ESF configurations were assembled using either specially designed composite titanium and silicone (composite group) or solid titanium (solid group) connecting rods. Mechanical testing was performed in axial loading and 4-point cranial-caudal bending. Stiffness was determined at a low and high-load range, and was considered increasing and nonlinear if the stiffness at high loads was greater than at low loads. The stiffness of the solid group was linear in all testing modes and configurations. Bilateral composite fixators had a nonlinear increasing stiffness in axial loading and cranial-caudal bending. Unilateral composite fixators had a nonlinear increasing stiffness in axial loading, but not cranial-caudal bending. Solid connecting rods conferred a higher stiffness in all testing modes and configurations. Composite connecting rods resulted in nonlinear increasing axial and bending stiffness in bilateral fixators, and in axial load in unilateral fixators. Conventional ESF can be constructed so that the stiffness increases as load increases. This provides the surgeon with additional options to control the local mechanical environment of a healing fracture, which may be used to enhance fracture healing.

  5. Reduction of intradiscal pressure by the use of polycarbonate-urethane rods as compared to titanium rods in posterior thoracolumbar spinal fixation.

    Science.gov (United States)

    Jacobs, Eva; Roth, Alex K; Arts, Jacobus J; van Rhijn, Lodewijk W; Willems, Paul C

    2017-08-21

    Loss of sagittal alignment and balance in adult spinal deformity can cause severe pain, disability and progressive neurological deficit. When conservative treatment has failed, spinal fusion using rigid instrumentation is currently the salvage treatment to stop further curve progression. However, fusion surgery is associated with high revision rates due to instrumentation failure and proximal junctional failure, especially if patients also suffer from osteoporosis. To address these drawbacks, a less rigid rod construct is proposed, which is hypothesized to provide a more gradual transition of force and load distribution over spinal segments in comparison to stiff titanium rods. In this study, the effect of variation in rod stiffness on the intradiscal pressure (IDP) of fixed spinal segments during flexion-compression loading was assessed. An ex vivo multisegment (porcine) flexion-compression spine test comparing rigid titanium rods with more flexible polycarbonate-urethane (PCU) rods was used. An increase in peak IDP was found for both the titanium and PCU instrumentation groups as compared to the uninstrumented controls. The peak IDP for the spines instrumented with the PCU rods was significantly lower in comparison to the titanium instrumentation group. These results demonstrated the differences in mechanical load transfer characteristics between PCU and titanium rod constructs when subjected to flexion-compression loading. The concept of stabilization with a less rigid rod may be an alternative to fusion with rigid instrumentation, with the aim of decreasing mechanical stress on the instrumented segments and the possible benefit of a decrease in the incidence of screw pullout.

  6. Controlled functionalization of nanoparticles & practical applications

    Science.gov (United States)

    Rashwan, Khaled

    With the increasing use of nanoparticles in both science and industry, their chemical modification became a significant part of nanotechnology. Unfortunately, most commonly used procedures provide just randomly functionalized materials. The long-term objective of our work is site- and stoichiometrically-controlled functionalization of nanoparticles with the utilization of solid supports and other nanostructures. On the examples of silica nanoparticles and titanium dioxide nanorods, we have obtained results on the solid-phase chemistry, method development, and modeling, which advanced us toward this goal. At the same time, we explored several applications of nanoparticles that will benefit from the controlled functionalization: imaging of titanium-dioxide-based photocatalysts, bioimaging by fluorescent nanoparticles, drug delivery, assembling of bone implants, and dental compositions. Titanium dioxide-based catalysts are known for their catalytic activity and their application in solar energy utilization such as photosplitting of water. Functionalization of titanium dioxide is essential for enhancing bone-titanium dioxide nanotube adhesion, and, therefore, for its application as an interface between titanium implants and bones. Controlled functionalization of nanoparticles should enhance sensitivity and selectivity of nanoassemblies for imaging and drug delivery applications. Along those lines, we studied the relationship between morphology and surface chemistry of nanoparticles, and their affinity to organic molecules (salicylic and caffeic acid) using Langmuir adsorption isotherms, and toward material surfaces using SEM- and TEM-imaging. We focused on commercial samples of titanium dioxide, titanium dioxide nanorods with and without oleic acid ligands, and differently functionalized silica nanoparticles. My work included synthesis, functionalization, and characterization of several types of nanoparticles, exploring their application in imaging, dentistry, and bone

  7. Control Improvisation with Application to Music

    Science.gov (United States)

    2013-11-04

    Control Improvisation with Application to Music Alexandre Donze Sophie Libkind Sanjit A. Seshia David Wessel Electrical Engineering and Computer...to Music 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...domain of music . More speci cally, we consider the scenario of generating a monophonic Jazz melody (solo) on a given song harmonization. The music is

  8. Database access control within a Java application

    OpenAIRE

    Plantec, Alain; Ribaud, Vincent; Saliou, Philippe

    2003-01-01

    International audience; The purpose of the work described in this article is to use database security mechanism as a data access control model in a Java application, developed through an UML-based process. This work relies on the CASE tool Designer from the Oracle company and its associated user and security policy. The three axis of this work are the following ones : • Introducing class diagrams towards Designer analysis and design models (entity-relation ship diagram, design diagrams). • Us...

  9. Experimental Study on Surrogate Nuclear Fuel Rods under Reversed Cyclic Bending

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong [ORNL; Wang, Jy-An John [ORNL

    2017-01-01

    The mechanical behavior of spent nuclear fuel (SNF) rods under reversed cyclic bending or bending fatigue must be understood to evaluate their vibration integrity in a transportation environment. This is especially important for high-burnup fuels (>45 GWd/MTU), which have the potential for increased structural damage. It has been demonstrated that the bending fatigue of SNF rods can be effectively studied using surrogate rods. In this investigation, surrogate rods made of stainless steel (SS) 304 cladding and aluminum oxide pellets were tested under load or moment control at a variety of amplitude levels at 5 Hz using the Cyclic Integrated Reversible-Bending Fatigue Tester developed at Oak Ridge National Laboratory. The behavior of the rods was further characterized using flexural rigidity and hysteresis data, and fractography was performed on the failed rods. The proposed surrogate rods captured many of the characteristics of deformation and failure mode observed in SNF, including the linear-to-nonlinear deformation transition and large residual curvature in static tests, PPI and PCMI failure mechanisms, and large variation in the initial structural condition. Rod degradation was measured and characterized by measuring the flexural rigidity; the degradation of the rigidity depended on both the moment amplitude applied and the initial structural condition of the rods. It was also shown that a cracking initiation site can be located on the internal surface or the external surface of cladding. Finally, fatigue damage to the bending rods can be described in terms of flexural rigidity, and the fatigue life of rods can be predicted once damage model parameters are properly evaluated. The developed experimental approach, test protocol, and analysis method can be used to study the vibration integrity of SNF rods in the future.

  10. Magnetically labeled cells with surface-modified fe3 o4 spherical and rod-shaped magnetic nanoparticles for tissue engineering applications.

    Science.gov (United States)

    Gil, Sara; Correia, Clara R; Mano, João F

    2015-04-22

    Magnetically targeted cells with internalized magnetic nanoparticles (MNPs) could allow the success of cell transplantation and cell-based therapies, overcoming low cell retention that occurs when delivering cells by intravenous or local injection. Upon magnetization, these cells could then accumulate and stimulate the regeneration of the tissue in situ. Magnetic targeting of cells requires a detailed knowledge between interactions of engineered nanomaterials and cells, in particular the influence of shape and surface functionalization of MNPs. For the first time, cellular internalization of amino surface-modified iron oxide nanoparticles of two different shapes (nanospheres or nanorods) is studied. MNPs show high cellular uptake and labeled cells could exhibit a strong reaction with external magnetic fields. Compared to nanorods, nanospheres show better internalization efficiency, and labeled cells exhibit strong transportation reaction with external magnetic fields. Contiguous viable cell-sheets are developed by magnetic-force-based tissue engineering. The results confirm that the developed magnetic-responsive nano-biomaterials have potential applicability in tissue engineering or cellular therapies. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Optimal Control Applications in Space Situational Awareness

    Science.gov (United States)

    Holzinger, Marcus J.

    There are currently more than 19,000 trackable objects in Earth orbit, 1,300 of which are active. With so many objects populating the space object catalog and new objects being added at an ever increasing rate, ensuring continued access to space is quickly becoming a cornerstone of national security policies. Space Situational Awareness (SSA) supports space operations, space flight safety, implementing international treaties and agreements, protecting of space capabilities, and protecting of national interests. With respect to objects in orbit, this entails determining their location, orientation, size, shape, status, purpose, current tasking, and future tasking. For active spacecraft capable of propulsion, the problem of determining these characteristics becomes significantly more difficult. Optimal control techniques can be applied to object correlation, maneuver detection, maneuver/spacecraft characterization, fuel usage estimation, operator priority inference, intercept capability characterization, and fuel-constrained range set determination. A detailed mapping between optimal control applications and SSA object characterization support is reviewed and related literature visited. Each SSA application will be addressed starting from first-principles using optimal control techniques. For each application, several examples of potential utility are given and discussed.

  12. Semi-analytical method for calculating aeroelastic effect of profiled rod flying at high velocity

    Directory of Open Access Journals (Sweden)

    Hui-jun Ning

    2015-03-01

    Full Text Available The key technique of a kinetic energy rod (KER warhead is to control the flight attitude of rods. The rods are usually designed to different shapes. A new conceptual KER named profiled rod which has large L/D ratio is described in this paper. The elastic dynamic equations of this profiled rod flying at high velocity after detonation are set up on the basis of Euler-Bernoulli beam, and the aeroelastic deformation of profiled rod is calculated by semi-analytical method for calculating the vibration characteristics of variable cross-section beam. In addition, the aeroelastic deformation of the undeformed profiled rod and the aeroelastic deformation of deformed profiled rod which is caused by the detonation of explosive are simulated by computational fluid dynamic and finite element method (CFD/FEM, respectively. A satisfactory agreement of these two methods is obtained by the comparison of two methods. The results show that the semi-analytical method for calculating the vibration characteristics of variable cross-section beam is applied to analyze the aeroelastic deformation of profiled rod flying at high velocity.

  13. Synthesis of Ag-ZnO with multiple rods (multipods) morphology and its application in the simultaneous photo-catalytic degradation of methyl orange and methylene blue.

    Science.gov (United States)

    Arab Chamjangali, M; Bagherian, G; Javid, A; Boroumand, S; Farzaneh, N

    2015-11-05

    In this study, the photo-decolorization of a mixture of methylene blue (MB) and methyl orange (MO) was investigated using Ag-ZnO multipods. The photo-catalyst used, ZnO multipods, was successfully synthesized. The surface of ZnO microstructure was modified by deposition of different amounts of Ag nanoparticles (Ag NPs) using the photo-reduction method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis and atomic absorption spectroscopy. The photo-catalytic efficiency of Ag-ZnO is mainly controlled by the amount of Ag NPs deposited on the ZnO surface. The results obtained suggest that Ag-ZnO containing 6.5% Ag NPs, has the highest photo-catalytic performance in the simultaneous photo-degradation of dyes at a shorter time. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Site controlled red-yellow-green light emitting InGaN quantum discs on nano-tipped GaN rods

    Science.gov (United States)

    Conroy, M.; Li, H.; Kusch, G.; Zhao, C.; Ooi, B.; Edwards, P. R.; Martin, R. W.; Holmes, J. D.; Parbrook, P. J.

    2016-05-01

    We report a method of growing site controlled InGaN multiple quantum discs (QDs) at uniform wafer scale on coalescence free ultra-high density (>80%) nanorod templates by metal organic chemical vapour deposition (MOCVD). The dislocation and coalescence free nature of the GaN space filling nanorod arrays eliminates the well-known emission problems seen in InGaN based visible light sources that these types of crystallographic defects cause. Correlative scanning transmission electron microscopy (STEM), energy-dispersive X-ray (EDX) mapping and cathodoluminescence (CL) hyperspectral imaging illustrates the controlled site selection of the red, yellow and green (RYG) emission at these nano tips. This article reveals that the nanorod tips' broad emission in the RYG visible range is in fact achieved by manipulating the InGaN QD's confinement dimensions, rather than significantly increasing the In%. This article details the easily controlled method of manipulating the QDs dimensions producing high crystal quality InGaN without complicated growth conditions needed for strain relaxation and alloy compositional changes seen for bulk planar GaN templates.We report a method of growing site controlled InGaN multiple quantum discs (QDs) at uniform wafer scale on coalescence free ultra-high density (>80%) nanorod templates by metal organic chemical vapour deposition (MOCVD). The dislocation and coalescence free nature of the GaN space filling nanorod arrays eliminates the well-known emission problems seen in InGaN based visible light sources that these types of crystallographic defects cause. Correlative scanning transmission electron microscopy (STEM), energy-dispersive X-ray (EDX) mapping and cathodoluminescence (CL) hyperspectral imaging illustrates the controlled site selection of the red, yellow and green (RYG) emission at these nano tips. This article reveals that the nanorod tips' broad emission in the RYG visible range is in fact achieved by manipulating the InGaN QD

  15. Optimal control novel directions and applications

    CERN Document Server

    Aronna, Maria; Kalise, Dante

    2017-01-01

    Focusing on applications to science and engineering, this book presents the results of the ITN-FP7 SADCO network’s innovative research in optimization and control in the following interconnected topics: optimality conditions in optimal control, dynamic programming approaches to optimal feedback synthesis and reachability analysis, and computational developments in model predictive control. The novelty of the book resides in the fact that it has been developed by early career researchers, providing a good balance between clarity and scientific rigor. Each chapter features an introduction addressed to PhD students and some original contributions aimed at specialist researchers. Requiring only a graduate mathematical background, the book is self-contained. It will be of particular interest to graduate and advanced undergraduate students, industrial practitioners and to senior scientists wishing to update their knowledge.

  16. Site controlled Red-Yellow-Green light emitting InGaN Quantum Discs on nano-tipped GaN rods

    KAUST Repository

    Conroy, Michele Ann

    2016-03-10

    We report a method of growing site controlled InGaN multiple quantum discs (QDs) at uniform wafer scale on coalescence free ultra-high density (>80%) nanorod templates by metal organic chemical vapour deposition (MOCVD). The dislocation and coalescence free nature of the GaN space filling nanorod arrays eliminates the well-known emission problems seen in InGaN based visible light sources that these types of crystallographic defects cause. Correlative scanning transmission electron microscopy (STEM), energy-dispersive x-ray (EDX) mapping and cathodoluminescence (CL) hyperspectral imaging illustrates the controlled site selection of the red, yellow and green (RYG) emission at these nano tips. This article reveals that the nanorod tips’ broad emission in the RYG visible range is in fact achieved by manipulating the InGaN QD’s confinement dimensions, rather than significantly increasing the In%. This article details the easily controlled method of manipulating the QDs dimensions producing high crystal quality InGaN without complicated growth conditions needed for strain relaxation and alloy compositional changes seen for bulk planar GaN templates.

  17. Robust and Adaptive Control With Aerospace Applications

    CERN Document Server

    Lavretsky, Eugene

    2013-01-01

    Robust and Adaptive Control shows the reader how to produce consistent and accurate controllers that operate in the presence of uncertainties and unforeseen events. Driven by aerospace applications the focus of the book is primarily on continuous-dynamical systems.  The text is a three-part treatment, beginning with robust and optimal linear control methods and moving on to a self-contained presentation of the design and analysis of model reference adaptive control (MRAC) for nonlinear uncertain dynamical systems. Recent extensions and modifications to MRAC design are included, as are guidelines for combining robust optimal and MRAC controllers. Features of the text include: ·         case studies that demonstrate the benefits of robust and adaptive control for piloted, autonomous and experimental aerial platforms; ·         detailed background material for each chapter to motivate theoretical developments; ·         realistic examples and simulation data illustrating key features ...

  18. Compact Hybrid Laser Rod and Laser System

    Science.gov (United States)

    Busch, George E. (Inventor); Amzajerdian, Farzin (Inventor); Pierrottet, Diego F. (Inventor)

    2017-01-01

    A hybrid fiber rod includes a fiber core and inner and outer cladding layers. The core is doped with an active element. The inner cladding layer surrounds the core, and has a refractive index substantially equal to that of the core. The outer cladding layer surrounds the inner cladding layer, and has a refractive index less than that of the core and inner cladding layer. The core length is about 30 to 2000 times the core diameter. A hybrid fiber rod laser system includes an oscillator laser, modulating device, the rod, and pump laser diode(s) energizing the rod from opposite ends. The rod acts as a waveguide for pump radiation but allows for free-space propagation of laser radiation. The rod may be used in a laser resonator. The core length is less than about twice the Rayleigh range. Degradation from single-mode to multi-mode beam propagation is thus avoided.

  19. Determination of Ultimate Torque for Multiply Connected Cross Section Rod

    Directory of Open Access Journals (Sweden)

    V. L. Danilov

    2015-01-01

    Full Text Available The aim of this work is to determine load-carrying capability of the multiply cross-section rod. This calculation is based on the model of the ideal plasticity of the material, so that the desired ultimate torque is a torque at which the entire cross section goes into a plastic state.The article discusses the cylindrical multiply cross-section rod. To satisfy the equilibrium equation and the condition of plasticity simultaneously, two stress function Ф and φ are introduced. By mathematical transformations it has been proved that Ф is constant along the path, and a formula to find its values on the contours has been obtained. The paper also presents the rationale of the line of stress discontinuity and obtained relationships, which allow us to derive the equations break lines for simple interaction of neighboring circuits, such as two lines, straight lines and circles, circles and a different sign of the curvature.After substitution into the boundary condition at the end of the stress function Ф and mathematical transformations a formula is obtained to determine the ultimate torque for the multiply cross-section rod.Using the doubly connected cross-section and three-connected cross-section rods as an example the application of the formula of ultimate torque is studied.For doubly connected cross-section rod, the paper offers a formula of the torque versus the radius of the rod, the aperture radius and the distance between their centers. It also clearly demonstrates the torque dependence both on the ratio of the radii and on the displacement of hole. It is shown that the value of the torque is more influenced by the displacement of hole, rather than by the ratio of the radii.For the three-connected cross-section rod the paper shows the integration feature that consists in selection of a coordinate system. As an example, the ultimate torque is found by two methods: analytical one and 3D modeling. The method of 3D modeling is based on the Nadai

  20. Investigation of wave propagation in double cylindrical rods considering the effect of prestress

    Science.gov (United States)

    Li, Chunlei; Han, Qiang; Liu, Yijie; Liu, Xiucheng; Wu, Bin

    2015-09-01

    This paper presents the investigation of guided wave propagation in prestressed double-cylinder structure. Based on Hertzian contact theory, the interaction between two rods is treated as a plane strain problem and the stress state in the waveguide under the static load is obtained. The stress state is considered as a prestressed configuration for elastic wave propagation analysis in double cylindrical rods. The elastodynamic equation of the prestressed structure is established with the updated Lagrangian formulation and the wave finite element (WFE) method. Firstly, the equation is verified by the application on an aluminum rod compared with the Euler-Bernoulli beam theory. Then, dispersion curves for single rod and double cylindrical rods without prestress are computed. Besides, at the dimensionless frequency 0.25 the propagating modes in double cylindrical rods are identified with mode shapes and displacement vectors. The guided waves in double rods consist of the modes different from single rod. Particularly, there exist two kinds of torsional-like modes, one of which has a twist center and the other has two. The latter changes obviously with the increase of prestress in the waveguide. At low frequencies, torsional-like modes are very sensitive to the variation of prestress; in addition, the prestress configuration has little influence on propagating modes at mid-frequencies but some at high frequencies.

  1. Biosynthesis of Zinc Oxide Nano-rods Using Xanthomonas campestris

    Directory of Open Access Journals (Sweden)

    Zahra sadat Mahdi

    2017-06-01

    Full Text Available Introduction: one dimensional nanocrystals especially nano-rods have attracted a great deal of attention due to their unique properties and wide applications in industry. Chemical and physical methods which are currently used to produce zinc oxide nano- rods, often leave toxic chemicals on surface of nanoparticles limiting their applications for health and medical purposes. Therefore, biological synthesis of zinc oxide nanoparticles has been considered as an environmentally friendly process and a potential alternative to chemical and physical methods. Materials and methods: Nano-rods of zinc oxide were produced by Xanthomonas campestris using zinc nitrate hexa hydrate as substrate, in a shaker incubator at 37 ° C and pH 7. The powder produced was then calcined at 600 ° C for 2 hours after drying. The synthesized ZnO nanoparticles were characterized using FTIR, XRD, SEM, EDX and UV–vis spectroscopy. Results: FTIR analysis was used to identify functional groups involved in the biosynthesis of ZnO NPs. The peak observed at 563 cm-1 corresponds to the stretching vibrations of ZnO NPs. XRD analysis revealed that the hexagonal ZnO nanoparticles synthesized were pure and crystalline in nature. The morphology and size of the powder were investigated using SEM analysis and the results showed that ZnO nano-rods have a diameter ranging from 122–200 nm with an average length about 300 nm. EDX analysis was performed for determination of the elemental composition and purity of samples. The recorded EDX spectrum revealed the high purity of the synthesized ZnO nano-rods without detection of any impurities. The absorption peak at 376 nm indicating the presence of zinc oxide nanoparticles was further confirmed by UV-Vis spectroscopy. Discussion and conclusion: The current research work describes a low-cost, unreported, nontoxic, simple, safe and eco-friendly method for the biosynthesis of zinc oxide nanoparticle using xanthomonas campestris as the reducing

  2. SCADOP: Phenomenological modeling of dryout in nuclear fuel rod bundles

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Arnab, E-mail: arnie@barc.gov.in; Chandraker, D.K., E-mail: dineshkc@barc.gov.in; Vijayan, P.K., E-mail: vijayanp@barc.gov.in

    2015-11-15

    applicable to tubes as well as rod bundles. For application to rod bundles, the flow field was calculated using subchannel methodology. The model developed has been validated against experimental data in tubes and rod bundles. In the process a computer code SCADOP has been developed for analysis of dryout in rod bundles.

  3. Manipulating electromagnetic wave propagating non-reciprocally by a chain of ferrite rods.

    Science.gov (United States)

    Ju, Cheng; Wu, Rui-Xin; Li, Zhen; Poo, Yin; Liu, Shi-Yang; Lin, Zhi-Fang

    2017-09-04

    We demonstrated that non-reciprocal wave propagation could be manipulated by a magnetic rod chain under bias DC magnetic fields. Made of ferrite material YIG and designed working in the microwave X-band, the rod chain exhibited almost a total reflection when the incident wave obliquely impinged on the rod chain, but exhibited nearly a total transmission when the wave reversed its propagation direction. The non-reciprocal wave propagation was due to the non-reciprocal diffraction of the rod chain for the orders 0 and ± 1. Further, the non-reciprocal wave propagation was directly observed by using the field mapping technique. The unique non-reciprocal wave property of the magnetic rod chain provides a new way to control the flow of EM waves.

  4. History and applications in controlled environments

    Energy Technology Data Exchange (ETDEWEB)

    Downs, R.J. [North Carolina State Univ., Raleigh, NC (United States)

    1994-12-31

    The widespread application of electric (often called artificial) light in greenhouses, growing rooms, and plant growth chambers would presuppose that the role of phytochrome would be considered in the selection and use of such lighting systems. Part of the problem is that many students, and indeed an unfortunate number of senior scientists, seem to regard phytochrome as a laboratory phenomenon without much application in the real world. They simply have not grasped the concept that phytochrome is functioning through all stages of plant development, wherever plants are grown. It is certainly true, as Meijer (1971) stated, that one cannot compare experimental results obtained under very strict laboratory conditions with plant irradiation in glasshouses and in growth rooms. For example, the action spectrum for flowering of the long-day plant, Hyoscyamus niger, clearly shows that red radiation is the most efficient portion of the spectrum for promoting flower initiation, but in practical photoperiod control red or fluorescent lamps do not promote flowering nearly as well as the mixture of red and far-red in incandescent lamps. Nevertheless, much evidence exists that documents phytochrome control of plant growth and development in controlled environments and under natural conditions. When Karl Norris developed the first practical portable spectroradiometer about 1962 some of the first measurements were to determine the red/far-red ratios under tree canopies. These measurements showed clearly the predominance of far-red in the understory and suggested that far-red was contributing to the elongation exhibited by many species growing in the shade, and possibly was a factor in the induction of light requirements in seeds. Subsequently we used Catalpa leaves as far-red filters to make light-insensitive lettuce seed light requiring.

  5. Tipping Time of a Quantum Rod

    Science.gov (United States)

    Parrikar, Onkar

    2010-01-01

    The behaviour of a quantum rod, pivoted at its lower end on an impenetrable floor and restricted to moving in the vertical plane under the gravitational potential, is studied analytically under the approximation that the rod is initially localized to a "small-enough" neighbourhood around the point of classical unstable equilibrium. It is shown…

  6. Computing Temperatures In Optically Pumped Laser Rods

    Science.gov (United States)

    Farrukh, Usamah O.

    1991-01-01

    Computer program presents new model solving temperature-distribution problem for laser rods of finite length and calculates both radial and axial components of temperature distributions in these rods. Contains several self-checking schemes to prevent over-writing of memory blocks and to provide simple tracing of information in case of trouble. Written in Microsoft FORTRAN 77.

  7. Self-contact for rods on cylinders

    NARCIS (Netherlands)

    G.H.M. van der Heijden; M.A. Peletier (Mark); R. Planqué (Robert)

    2004-01-01

    textabstractWe study self-contact phenomena in elastic rods that are constrained to lie on a cylinder. By choosing a particular set of variables to describe the rod centerline the variational setting is made particularly simple: the strain energy is a second-order functional of a single scalar

  8. Controllable Synthesis of Formaldehyde Modified Manganese Oxide Based on Gas-Liquid Interfacial Reaction and Its Application of Electrochemical Sensing.

    Science.gov (United States)

    Bai, Wushuang; Sheng, Qinglin; Nie, Fei; Zheng, Jianbin

    2015-12-30

    Controllable synthesis of manganese oxides was performed via a simple one-step synthetic method. Then obtained manganese oxides which exhibit flower-like, cloud-like, hexagon-like, and rod-like morphologies were modified by formaldehyde based on a simple self-made gas-liquid reaction device respectively and the modified manganese oxides with coral-like, scallop-like and rod-like morphology were synthesized accordingly. The obtained materials were characterized and the formation mechanism was also researched. Then the modified manganese oxides were used to fabricate electrochemical sensors to detect H2O2. Comparison of electrochemical properties between three kinds of modified manganese oxides was investigated and the best one has been successfully employed as H2O2 sensor which shows a low detection limit of 0.01 μM, high sensitivity of 162.69 μA mM(-1) cm(-2), and wide linear range of 0.05 μM-12.78 mM. The study provides a new method for controllable synthesis of metal oxides, and electrochemical application of formaldehyde modified manganese oxides will provides a new strategy for electrochemical sensing with high performance, low cost, and simple fabrication.

  9. Application of control theory to dynamic systems simulation

    Science.gov (United States)

    Auslander, D. M.; Spear, R. C.; Young, G. E.

    1982-01-01

    The application of control theory is applied to dynamic systems simulation. Theory and methodology applicable to controlled ecological life support systems are considered. Spatial effects on system stability, design of control systems with uncertain parameters, and an interactive computing language (PARASOL-II) designed for dynamic system simulation, report quality graphics, data acquisition, and simple real time control are discussed.

  10. Using Variable Speed Control on Pump Application

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Aida Spahiu

    2012-06-01

    Full Text Available Pumps are one of the most common variable speed drive (VSD system applications and special interest has focused on improving their energy efficiency by using variable speed control instead of throttling or other less efficient flow control methods. Pumps are the single largest user of electricity in industry in the European Union, consuming 160 TWh per annum of electricity and accounting for 79 million tonnes of carbon dioxide (CO2 emissions [1]. Centrifugal pumps are the most likely pump style to provide a favorable return based on energy savings when applied with a variable speed drive. To help illustrate this, are conducted benchmark testing to document various head and flow scenarios and their corresponding effect on energy savings. Paper shows the relationship of static and friction head in the energy efficiency equation and the effect of motor, pump and VSD efficiencies. The received results are good reference points for engineers and managers of water sector in Albania to select the best prospects for maximizing efficiency and energy savings.

  11. IDCDACS: IDC's Distributed Application Control System

    Science.gov (United States)

    Ertl, Martin; Boresch, Alexander; Kianička, Ján; Sudakov, Alexander; Tomuta, Elena

    2015-04-01

    The Preparatory Commission for the CTBTO is an international organization based in Vienna, Austria. Its mission is to establish a global verification regime to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which bans all nuclear explosions. For this purpose time series data from a global network of seismic, hydro-acoustic and infrasound (SHI) sensors are transmitted to the International Data Centre (IDC) in Vienna in near-real-time, where it is processed to locate events that may be nuclear explosions. We newly designed the distributed application control system that glues together the various components of the automatic waveform data processing system at the IDC (IDCDACS). Our highly-scalable solution preserves the existing architecture of the IDC processing system that proved successful over many years of operational use, but replaces proprietary components with open-source solutions and custom developed software. Existing code was refactored and extended to obtain a reusable software framework that is flexibly adaptable to different types of processing workflows. Automatic data processing is organized in series of self-contained processing steps, each series being referred to as a processing pipeline. Pipelines process data by time intervals, i.e. the time-series data received from monitoring stations is organized in segments based on the time when the data was recorded. So-called data monitor applications queue the data for processing in each pipeline based on specific conditions, e.g. data availability, elapsed time or completion states of preceding processing pipelines. IDCDACS consists of a configurable number of distributed monitoring and controlling processes, a message broker and a relational database. All processes communicate through message queues hosted on the message broker. Persistent state information is stored in the database. A configurable processing controller instantiates and monitors all data processing

  12. Design, Manufacture and Analysis of Al/SiC MMCs for Connecting Rod

    Science.gov (United States)

    Ramasubramanian, S.; Chandrasekaran, M.; Sridhar, R.; Karunakaran, K.

    2017-03-01

    The Metal matrix composite materials is particularly are widely used in automotive engineering applications. In this work discuss with production of Al/SiC composite and investigate it’s suitability for the application on Connecting Rod. The results were compared with conventional material C70 Steel. The connecting rod is manufactured using the stir casting method. The basic properties were obtained by mechanical testing. The test results were used for FEA. The connecting rod is designed and meshed using solid works and hyper mesh, and then analysis is done used by ANSYS work bench 14.0 software. The results show that the composite connecting rod is more efficient than the conventional ones.

  13. Lightning Current Observation on UHVAC Transmission Lines by Improved Magnetic Steel Rod Method

    Directory of Open Access Journals (Sweden)

    Anfeng Jiang

    2014-09-01

    Full Text Available Lightning stroke is the main threaten to the safe operation of UHVAC transmission lines. The magnetic steel rod method had been widely used as a traditional method for lightning accident and lightning current investigation in high voltage transmission lines. For the application of the magnetic steel rod method on UHVAC transmission lines, this paper proposed a practical and easy improved method of installing the magnetic steel rods directly on the transmission towers. The residual magnetism curve and accuracy verification of the proposed method was obtained through complex steel structure impulse current experiments. The magnetic steel rod location on UHVAC transmission tower was analyzed by the numerical analysis software MagNet. The application results of the proposed method on the first demonstration and test UHVAC transmission line is presented. The obtained datasets after one storm season was analyzed through Electromagnetic Transients Program. It is shown that the proposed method is feasible.

  14. Induced Current Measurement of Rod Vibrations

    Science.gov (United States)

    Sawicki, Charles A.

    2003-01-01

    The longitudinal normal modes of vibration of rods are similar to the modes seen in pipes open at both ends. A maximum of particle displacement exists at both ends and an integral number (n) of half wavelengths fit into the rod length. The frequencies fn of the normal modes is given by Eq. (1), where L is the rod length and V is the wave velocity: fn = nV/2L. Many methods have been used to measure the velocity of these waves. The Kundt's tube method commonly used in student labs will not be discussed here. A simpler related method has been described by Nicklin.2 Kluk3 measured velocities in a wide range of materials using a frequency counter and microphone to study sounds produced by impacts. Several earlier methods4,5 used phonograph cartridges complete with needles to detect vibrations in excited rods. A recent interesting experiment6 used wave-induced changes in magnetization produced in an iron rod by striking one end. The travel time, measured as the impulsive wave reflects back and forth, gave the wave velocity for the iron rod. In the method described here, a small magnet is attached to the rod with epoxy, and vibrations are detected using the current induced in a few loops of wire. The experiment is simple and yields very accurate velocity values.

  15. Buffer Rod Design for Measurement of Specific Gravity in the Processing of Industrial Food Batters

    DEFF Research Database (Denmark)

    Fox, Paul D.; Smith, Penny Probert

    2002-01-01

    A low cost perspex buffer rod design for the measurement of specific gravity during the processing of industrial food batters is reported. Operation was conducted in pulsed mode using a 2.25 MHz, 15 mm diameter transducer and the intensity and an analytic calibration curve relating buffer rod...... output to specific gravity is obtained. The probe design may have application to other similar mixtures or industrial sludges in which similar material properties are observed....

  16. Bijels stabilized using rod-like particles.

    Science.gov (United States)

    Hijnen, Niek; Cai, Dongyu; Clegg, Paul S

    2015-06-14

    Bicontinuous interfacially jammed emulsion gels, in short 'bijels', rely on a trapped layer of colloidal particles for their stability. These structures have traditionally been created using spherical colloidal particles. Here we show for the first time the use of rod-shape particles to stabilize bijels. We show that domain size decreases more rapidly with particle concentration in the case of rods compared to spheres. Large-scale analysis and detailed examination of images show that the packing fraction of rods is much higher than expected, in part, due to the role of 'flippers'.

  17. Electrically reconfigurable optical metamaterials based on orientationally ordered dispersions of metal nano-rods in dielectric fluids

    Science.gov (United States)

    Golovin, Andrii B.; Xiang, Jie; Nastishin, Yuriy A.; Lavrentovich, Oleg D.

    2010-08-01

    Optical metamaterials capture the imagination with potential applications such as sub-wave imaging, invisibility cloaking and solar energy collection. The challenge is to learn how to construct and reconfigure a metamaterial with a spatially varying refractive index. We describe an approach based on colloidal dispersion of metal nano-rods in a dielectric fluid placed in a non-uniform electric field. Because of the dielectrophoretic effect, the nano-rods accumulate in the regions with the maximum field and align along the field lines. High concentration of nano-rods lowers the effective local refractive index of the dispersion. The nano-rods are much smaller than the wavelength of light. We illustrate the approach with a dispersion of gold nanorods (length 40-70 nm, diameter 10-20 nm) in toluene, using flat and cylindrical cells. In the first case, the electric field is created by two mutually perpendicular electrodes, in the second case, it is created by two coaxial electrodes. When the field is applied, the initially isotropic dispersion of nanorods transforms into birefringent orientationally ordered structures with the director following the electric field lines. We describe how the optical properties of the field-induced structures are controlled by dichroism and birefringence of the dispersion and determine the spatial variation of the field-induced optical phase retardation. In cylindrical capillaries, the index gradient bends lights around the central electrode, thus reducing its visibility. Our approach can be used as a starting point for the development of self-assembled and reconfigurable optical metamaterials with optical properties controlled by the dielectrophoretic effect on submicron scales.

  18. Review of Recent Type-2 Fuzzy Controller Applications

    Directory of Open Access Journals (Sweden)

    Kevin Tai

    2016-06-01

    Full Text Available Type-2 fuzzy logic controllers (T2 FLC can be viewed as an emerging class of intelligent controllers because of their abilities in handling uncertainties; in many cases, they have been shown to outperform their Type-1 counterparts. This paper presents a literature review on recent applications of T2 FLCs. To follow the developments in this field, we first review general T2 FLCs and the most well-known interval T2 FLS algorithms that have been used for control design. Certain applications of these controllers include robotic control, bandwidth control, industrial systems control, electrical control and aircraft control. The most promising applications are found in the robotics and automotive areas, where T2 FLCs have been demonstrated and proven to perform better than traditional controllers. With the development of enhanced algorithms, along with the advancement in both hardware and software, we shall witness increasing applications of these frontier controllers.

  19. Application of a genetic algorithm for the optimization of enrichment zoning and Gadolinia fuel (UO{sub 2}/Gd{sub 2}O{sub 3}) rod designs in OPR1000s

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Tae Je; Kim, Jong Kyung [Hanyang University, Seoul (Korea, Republic of)

    2012-04-15

    A new effective methodology for optimizing the enrichment of low-enriched zones as well as gadolinia fuel (UO{sub 2}/Gd{sub 2}O{sub 3}) rod designs in PLUS7 fuel assemblies was developed to minimize the maximum peak power in the core and to maximize the cycle lifetime. An automated link code was developed to integrate the genetic algorithm (GA) and the core design code package of ALPHA/PHOENIX-P/ANC and to generate and evaluate the candidates to be optimized efficiently through the integrated code package. This study introduces an optimization technique for the optimization of gadolinia fuel rod designs in order to effectively reduce the peak powers for a few hot assemblies simultaneously during the cycle. Coupled with the gadolinia optimization, the optimum enrichments were determined using the same automated code package. Applying this technique to the reference core of Ulchin Unit 4 Cycle 11, the gadolinia fuel rods in each hot assembly were optimized to different numbers and positions from their original designs, and the maximum peak power was decreased by 2.5%, while the independent optimization technique showed a decrease of 1.6% for the same fuel assembly. The lower enrichments at the fuel rods adjacent to the corner gap (CG), guide tube (GT), and instrumentation tube (IT) were optimized from the current 4.1, 4.1, 4.1 w/o to 4.65, 4.2, 4.2 w/o. The increase in the cycle lifetime achieved through this methodology was 5 effective full-power days (EFPD) on an ideal equilibrium cycle basis while keeping the peak power as low as 2.3% compared with the original design.

  20. Analysis of Longitudinal Waves in Rod-Type Piezoelectric Phononic Crystals

    Directory of Open Access Journals (Sweden)

    Longfei Li

    2016-04-01

    Full Text Available Phononic crystals can be used to control elastic waves due to their frequency bands. This paper analyzes the passive and active control as well as the dispersion properties of longitudinal waves in rod-type piezoelectric phononic crystals over large frequency ranges. Based on the Love rod theory for modeling the longitudinal wave motions in the constituent rods and the method of reverberation-ray matrix (MRRM for deriving the member transfer matrices of the constituent rods, a modified transfer matrix method (MTMM is proposed for the analysis of dispersion curves by combining with the Floquet–Bloch principle and for the calculation of transmission spectra. Numerical examples are provided to validate the proposed MTMM for analyzing the band structures in both low and high frequency ranges. The passive control of longitudinal-wave band structures is studied by discussing the influences of the electrode’s thickness, the Poisson’s effect and the elastic rod inserts in the unit cell. The influences of electrical boundaries (including electric-open, applied electric capacity, electric-short and applied feedback control conditions on the band structures are investigated to illustrate the active control scheme. From the calculated comprehensive frequency spectra over a large frequency range, the dispersion properties of the characteristic longitudinal waves in rod-type piezoelectric phononic crystals are summarized.

  1. Anisotropy in CdSe quantum rods

    Energy Technology Data Exchange (ETDEWEB)

    Li, Liang-shi [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    The size-dependent optical and electronic properties of semiconductor nanocrystals have drawn much attention in the past decade, and have been very well understood for spherical ones. The advent of the synthetic methods to make rod-like CdSe nanocrystals with wurtzite structure has offered us a new opportunity to study their properties as functions of their shape. This dissertation includes three main parts: synthesis of CdSe nanorods with tightly controlled widths and lengths, their optical and dielectric properties, and their large-scale assembly, all of which are either directly or indirectly caused by the uniaxial crystallographic structure of wurtzite CdSe. The hexagonal wurtzite structure is believed to be the primary reason for the growth of CdSe nanorods. It represents itself in the kinetic stabilization of the rod-like particles over the spherical ones in the presence of phosphonic acids. By varying the composition of the surfactant mixture used for synthesis we have achieved tight control of the widths and lengths of the nanorods. The synthesis of monodisperse CdSe nanorods enables us to systematically study their size-dependent properties. For example, room temperature single particle fluorescence spectroscopy has shown that nanorods emit linearly polarized photoluminescence. Theoretical calculations have shown that it is due to the crossing between the two highest occupied electronic levels with increasing aspect ratio. We also measured the permanent electric dipole moment of the nanorods with transient electric birefringence technique. Experimental results on nanorods with different sizes show that the dipole moment is linear to the particle volume, indicating that it originates from the non-centrosymmetric hexagonal lattice. The elongation of the nanocrystals also results in the anisotropic inter-particle interaction. One of the consequences is the formation of liquid crystalline phases when the nanorods are dispersed in solvent to a high enough

  2. Application of magnetostrictive smart materials in rotor servoflap control

    Science.gov (United States)

    Ghorayeb, Solomon R.; Hansen, Toby T.; Straub, Friedrich K.

    1995-05-01

    The main theme of this research project has been to analytically develop a proof-of-concept design to demonstrate the effectiveness of a smart material actuator employing ETREMA TERFENOL-DTM for helicopter rotor servoflap control. This design enables the control of the rotor blade flap with an actuator embedded in the blade itself. By moving the control to the rotor blades, the swashplate system could be eliminated. Requirements such as applied load and motions were the key issues that needed to be accounted for in order to achieve a successful design employing the `giant' magnetostrictive material. A series of loading conditions characterized by an additive process of Steady-State. Cyclic, and Active control functions were considered for Sustained flight. Optimization of the overall system gave rise to a system gain of 3.7 for Sustained motion. At this same optimal gain value, and using an ETREMA TERFENOL-DTM rod length of at least 22.7 inches, a net peak-to-peak displacement of as high as 42 mils (1.07 mm) was obtained.

  3. Application framework for programmable network control

    NARCIS (Netherlands)

    Strijkers, R.; Cristea, M.; de Laat, C.; Meijer, R.; Clemm, A.; Wolter, R.

    2011-01-01

    We present a framework that enables application developers to create complex and application specific network services. The essence of our approach is to utilize programmable network elements to create a software representation of network elements in the application. We show that the typical pattern

  4. Applicator Training Manual for: Aquatic Weed Control.

    Science.gov (United States)

    Herron, James W.

    The aquatic weeds discussed in this manual include algae, floating weeds, emersed weeds, and submerged weeds. Specific requirements for pesticide application are given for static water, limited flow, and moving water situations. Secondary effects of improper application rates and faulty application are described. Finally, techniques of limited…

  5. The rod as an instrument of discipline

    OpenAIRE

    Milton Luiz Torres; Centro Universitário Adventista de São Paulo, São Paulo, SP

    2013-01-01

    Both in biblical literature as in ancient extrabiblical literature, the use of the rod appears primarily related to the capacity or to the authority of the one who holds it. It is, above all, an instrument of power. This article investigates the implications of using the rod as a tool of correction and discipline, taking into account the symbolism, culture and literary tradition associated with the use of that instrument of discipline for correction and transformation of those subjected to it...

  6. High Power Performance of Rod Fiber Amplifiers

    DEFF Research Database (Denmark)

    Johansen, Mette Marie; Michieletto, Mattia; Kristensen, Torben

    2015-01-01

    An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W.......An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W....

  7. IMPACT CONICAL ROD ON HARD LIMITER

    Directory of Open Access Journals (Sweden)

    Ulitin G.

    2014-12-01

    Full Text Available The problem is considered of longitudinal impact conical rod in article. A recommendation on the use of the approximate method of calculation is based on an analysis of the influence of design parameters on the value of the main oscillation frequency. There was obtained an equation of the displacement and stress of the rod. Engineering dependence has been proposed to determine the maximum force in the impact section.

  8. Microelectrophoresis of Silica Rods Using Confocal Microscopy

    Science.gov (United States)

    2017-01-01

    The electrophoretic mobility and the zeta potential (ζ) of fluorescently labeled colloidal silica rods, with an aspect ratio of 3.8 and 6.1, were determined with microelectrophoresis measurements using confocal microscopy. In the case where the colloidal particles all move at the same speed parallel to the direction of the electric field, we record a xyz-stack over the whole depth of the capillary. This method is faster and more robust compared to taking xyt-series at different depths inside the capillary to obtain the parabolic flow profile, as was done in previous work from our group. In some cases, rodlike particles do not move all at the same speed in the electric field, but exhibit a velocity that depends on the angle between the long axis of the rod and the electric field. We measured the orientation-dependent velocity of individual silica rods during electrophoresis as a function of κa, where κ–1 is the double layer thickness and a is the radius of the rod associated with the diameter. Thus, we determined the anisotropic electrophoretic mobility of the silica rods with different sized double layers. The size of the double layer was tuned by suspending silica rods in different solvents at different electrolyte concentrations. We compared these results with theoretical predictions. We show that even at already relatively high κa when the Smoluchowski limiting law is assumed to be valid (κa > 10), an orientation dependent velocity was measured. Furthermore, we observed that at decreasing values of κa the anisotropy in the electrophoretic mobility of the rods increases. However, in low polar solvents with κa mobility of the rods decreased. We argue that this decrease is due to end effects, which was already predicted theoretically. When end effects are not taken into account, this will lead to strong underestimation of the experimentally determined zeta potential. PMID:28045541

  9. Rod Outer Segment Development Influences AAV-Mediated Photoreceptor Transduction After Subretinal Injection.

    Science.gov (United States)

    Petit, Lolita; Ma, Shan; Cheng, Shun-Yun; Gao, Guangping; Punzo, Claudio

    2017-06-01

    Vectors based on the adeno-associated virus (AAV) are currently the preferred tools for delivering genes to photoreceptors (PR) in small and large animals. AAVs have been applied successfully in various models of PR dystrophies. However, unknown barriers still limit AAV's efficient application in several forms of severe PR degenerations due to insufficient transgene expression and/or treated cells at the time of injection. Optimizations of PR gene therapy strategies will likely benefit from the identification of the cellular factors that influence PR transduction. Interestingly, recent studies have shown that the AAV transduction profile of PRs differs significantly between neonatal and adult mouse retinas after subretinal injection. This phenomenon may provide clues to identify host factors that influence the efficiency of AAV-mediated PR transduction. This study demonstrates that rod outer segments are critical modulators of efficient AAV-mediated rod transduction. During retinal development, rod transduction correlated temporally and spatially with the differentiation order of PRs when vectors were introduced subretinally but not when introduced intravitreally. All subretinally injected vectors had an initial preference to transduce cones in the absence of formed rod outer segments and then displayed a preference for rods as the cells matured, independently of the expression cassette or AAV serotype. Consistent with this observation, altered development of rod outer segments was associated with a strong reduction of rod transduction and an increase in the percentage of transduced cones by 2- to 2.8-fold. A similar increase of cone transduction was observed in the adult retinal degeneration 1 (rd1) retina compared to wild-type mice. These results suggest that the loss of rod outer segments in diseased retinas could markedly affect gene transfer efficiency of AAV vectors by limiting the ability of AAVs to infect dying rods efficiently. This information could be

  10. Lawn and Turf Pest Control: A Guide for Commercial Applicators.

    Science.gov (United States)

    Khan, M. S.

    This manual is designed for use in training commercial pesticide applicators. It gives identification and control information for common lawn and turf diseases, insects, nematodes, weeds, and vertebrate pests. It also discusses phytotoxicity, environmental concerns, and application methods. (BB)

  11. The fractional - order controllers: Methods for their synthesis and application

    OpenAIRE

    Petras, I.

    2000-01-01

    This paper deals with fractional-order controllers. We outline mathematical description of fractional controllers and methods of their synthesis and application. Synthesis method is a modified root locus method for fractional-order systems and fractional-order controllers. In the next section we describe how to apply the fractional controller on control systems.

  12. Robot Control System based on Web Application and RFID Technology

    Directory of Open Access Journals (Sweden)

    Barenji Ali Vatankhah

    2015-01-01

    Full Text Available This paper discusses an integration driven framework for enabling the RFID based identification of parts to perform robotic distributor operations in the random mix based parts control based on web application. The RFID technology senses newly arriving parts to be distribution robot, the robot is able to recognize them and perform cooperative distributing via web-based application. The developed web application control system is implemented in the educational robotic arm. RFID system sends real time information from parts to the web application and web based application makes a decision for control of the robot arm, controller of robot controls the robot as based on the decision from web application. The proposed control system has increases the reconfiguration and scalability of robot system.

  13. Strike action electromagnetic machine for immersion of rod elements into ground

    Science.gov (United States)

    Usanov, K. M.; Volgin, A. V.; Chetverikov, E. A.; Kargin, V. A.; Moiseev, A. P.; Ivanova, Z. I.

    2017-10-01

    During construction, survey work, and drilling shallow wells by striking, operations associated with dipping and removing the rod elements are the most common. At the same time relatively long, with small diameter, elements, in which the ratio of length to diameter l/d is 100 or more, constitute a significant proportion. At present, the application of power pulse linear electromagnetic motors to drive drum machines is recognized to be highly effective. However, the mechanical method of transmission of shocks does not allow dipping long longitudinally unstable core elements. In this case, mechanical energy must be transferred from the motor to the rod through its side surface. The design of the strike action electromagnetic machine with a through axial channel for non-mechanical end striking of the pile of long, longitudinally unstable metal rods is proposed. Electromagnetic striking machine for non-mechanical end striking rod elements provides operations characterized by ecological compatibility, safety and high quality.

  14. Polyetheretherketone (PEEK) rods: short-term results in lumbar spine degenerative disease.

    Science.gov (United States)

    Colangeli, S; Barbanti Brodàno, G; Gasbarrini, A; Bandiera, S; Mesfin, A; Griffoni, C; Boriani, S

    2015-06-01

    Pedicle screw and rod instrumentation has become the preferred technique for performing stabilization and fusion in the surgical treatment of lumbar spine degenerative disease. Rigid fixation leads to high fusion rates but may also contribute to stress shielding and adjacent segment degeneration. Thus, the use of semirigid rods made of polyetheretherketone (PEEK) has been proposed. Although the PEEK rods biomechanical properties, such as anterior load sharing properties, have been shown, there are few clinical studies evaluating their application in the lumbar spine surgical treatment. This study examined a retrospective cohort of patients who underwent posterior lumbar fusion for degenerative disease using PEEK rods, in order to evaluate the clinical and radiological outcomes and the incidence of complications.

  15. Fuzzy Logic Controller for Low Temperature Application

    Science.gov (United States)

    Hahn, Inseob; Gonzalez, A.; Barmatz, M.

    1996-01-01

    The most common temperature controller used in low temperature experiments is the proportional-integral-derivative (PID) controller due to its simplicity and robustness. However, the performance of temperature regulation using the PID controller depends on initial parameter setup, which often requires operator's expert knowledge on the system. In this paper, we present a computer-assisted temperature controller based on the well known.

  16. Calcium-activated potassium current clamps the dark potential of vertebrate rods.

    Science.gov (United States)

    Moriondo, A; Pelucchi, B; Rispoli, G

    2001-07-01

    Vertebrate photoreceptors respond to light with a graded hyperpolarization from a membrane potential in the dark of approximately -35 mV. The present work investigates the physiological role of the Ca2+-activated K+ current in the photovoltage generation in mechanically isolated rods from salamander retina. Membrane current or voltage in isolated rods was recorded from light- and dark-adapted rods under voltage- or current-clamp conditions, respectively. In light-adapted rods of the salamander, selective blockade of Ca2+-activated K+ channels by means of charybdotoxin depolarized the plasma membrane of current-clamped rods by approximately 30 mV, from a resting potential of approximately -35 mV. A similar depolarization was observed if external Ca2+ (1 mM) was substituted with Ba2+ or Sr2+. Under control conditions, the injection of currents of increasing amplitude (up to -100 pA, to mimic the current entering the rod outer segment) could not depolarize the membrane potential beyond a saturating value of approximately -20 mV. However, in the presence of charybdotoxin, rods depolarized up to +20 mV. In experiments with dark-adapted current-clamped rods, charybdotoxin perfusion lead to transient depolarizations up to 0 mV and steady-state depolarizations of approximately 5 mV above the dark resting potential. Finally, the recovery phase of the voltage response to a flash of light in the presence of charybdotoxin showed a transient overshoot of the membrane potential. It was concluded that Ca2+-activated K+ current is necessary for clamping the rod photovoltage to values close to the dark potential, thus allowing faithful single photon detection and correct synaptic transmission.

  17. Model of ASTM Flammability Test in Microgravity: Iron Rods

    Science.gov (United States)

    Steinberg, Theodore A; Stoltzfus, Joel M.; Fries, Joseph (Technical Monitor)

    2000-01-01

    There is extensive qualitative results from burning metallic materials in a NASA/ASTM flammability test system in normal gravity. However, this data was shown to be inconclusive for applications involving oxygen-enriched atmospheres under microgravity conditions by conducting tests using the 2.2-second Lewis Research Center (LeRC) Drop Tower. Data from neither type of test has been reduced to fundamental kinetic and dynamic systems parameters. This paper reports the initial model analysis for burning iron rods under microgravity conditions using data obtained at the LERC tower and modeling the burning system after ignition. Under the conditions of the test the burning mass regresses up the rod to be detached upon deceleration at the end of the drop. The model describes the burning system as a semi-batch, well-mixed reactor with product accumulation only. This model is consistent with the 2.0-second duration of the test. Transient temperature and pressure measurements are made on the chamber volume. The rod solid-liquid interface melting rate is obtained from film records. The model consists of a set of 17 non-linear, first-order differential equations which are solved using MATLAB. This analysis confirms that a first-order rate, in oxygen concentration, is consistent for the iron-oxygen kinetic reaction. An apparent activation energy of 246.8 kJ/mol is consistent for this model.

  18. 75 FR 65658 - Importer of Controlled Substances; Notice of Application

    Science.gov (United States)

    2010-10-26

    ... applicants for registration to import a basic class of any controlled substances in schedule I or II are, and... classes of controlled substances listed in schedule II: Drug Schedule Raw Opium (9600) II Concentrate of...

  19. Aileron controls for wind turbine applications

    Science.gov (United States)

    Miller, D. R.; Putoff, R. L.

    1984-01-01

    Horizontal axis wind turbines which utilize partial or full variable blade pitch to regulate rotor speed were examined. The weight and costs of these systems indicated a need for alternate methods of rotor control. Aileron control is an alternative which has potential to meet this need. Aileron control rotors were tested on the Mod-O wind turbine to determine their power regulation and shutdown characteristics. Test results for a 20 and 38% chord aileron control rotor are presented. Test is shown that aileron control is a viable method for safety for safely controlling rotor speed, following a loss of general load.

  20. A cone beam computed tomography inspection method for fuel rod cladding tubes

    Science.gov (United States)

    Fu, Jian; Tan, Renbo; Wang, Qianli; Deng, Jingshan; Liu, Ming

    2012-10-01

    Fuel rods in nuclear power plants consist of UO2 pellets enclosed in Zirconium alloy (Zircaloy) cladding tube, which is composed of a body and a plug. The body is manufactured separately from the plug and, before its use, the plug is welded with the body. It is vitally important for the welding zone to remain free from defects after the fuel pellets are loaded into the cladding tube to prevent the radioactive fission products from leaking. X-ray computed tomography (CT) is in principle a feasible inspection method for the welding zone, but it faces several challenges due to the high attenuation of Zircaloy. In this paper, a cone beam CT method is proposed to address these issues and perform the welding flaw inspection. A Zircaloy compensator is adopted to narrow the signal range, a structure-based background removal technique to reveal the defects, a linear extension technique to determine the reference X-ray intensity signal and FDK algorithm to reconstruct the slice images. A prototype system, based on X-ray tube source and flat panel detector, has been developed and the experiments in this system have demonstrated that the welding void and the incomplete joint penetrations could be detected by this method. This approach may find applications in the quality control of nuclear fuel rods.

  1. Application of fuzzy logic in robot control

    Science.gov (United States)

    Kemppainen, Seppo; Roening, Juha

    1992-11-01

    During the past several years, fuzzy control has emerged as a suitable control strategy for many complex and nonlinear control problems. The control provided by fuzzy logic is both smooth and accurate. Also the 'if-then' rules of fuzzy control systems are easy to understand and relatively easy to develop. This paper presents a toolkit which is used in the implementation of fuzzy control system. The toolkit consists of C++ class library which computes inferences in fuzzy logic. The toolkit is used to implement a fuzzy control system which controls the movement of a simulated mobile robot. The proposed architecture consists of several rulesets. Each ruleset specializes in some control task, for example, there are rulesets for going around an obstacle, avoiding a moving obstacle, going through a door, etc. The multiple ruleset fuzzy control system is used to guide the simulated mobile robot to a given goal in an unknown environment. With the proposed multiple ruleset architecture complex control problems can be solved while single rulesets remain simple and efficient.

  2. In vitro degradation, flexural, compressive and shear properties of fully bioresorbable composite rods.

    Science.gov (United States)

    Felfel, R M; Ahmed, I; Parsons, A J; Walker, G S; Rudd, C D

    2011-10-01

    Several studies have investigated self-reinforced polylactic acid (SR-PLA) and polyglycolic acid (SR-PGA) rods which could be used as intramedullary (IM) fixation devices to align and stabilise bone fractures. This study investigated totally bioresorbable composite rods manufactured via compression moulding at ~100 °C using phosphate glass fibres (of composition 50P(2)O(5)-40CaO-5Na(2)O-5Fe(2)O(3) in mol%) to reinforce PLA with an approximate fibre volume fraction (v(f)) of 30%. Different fibre architectures (random and unidirectional) were investigated and pure PLA rods were used as control samples. The degradation profiles and retention of mechanical properties were investigated and PBS was selected as the degradation medium. Unidirectional (P50 UD) composite rods had 50% higher initial flexural strength as compared to PLA and 60% higher in comparison to the random mat (P50 RM) composite rods. Similar initial profiles for flexural modulus were also seen comparing the P50 UD and P50 RM rods. Higher shear strength properties were seen for P50 UD in comparison to P50 RM and PLA rods. However, shear stiffness values decreased rapidly (after a week) whereas the PLA remained approximately constant. For the compressive strength studies, P50 RM and PLA rods remained approximately constant, whilst for the P50 UD rods a significantly higher initial value was obtained, which decreased rapidly after 3 days immersion in PBS. However, the mechanical properties decreased after immersion in PBS as a result of the plasticisation effect of water within the composite and degradation of the fibres. The fibres within the random and unidirectional composite rods (P50 RM and P50 UD) degraded leaving behind microtubes as seen from the SEM micrographs (after 28 days degradation) which in turn created a porous structure within the rods. This was the main reason attributed for the increase seen in mass loss and water uptake for the composite rods (~17% and ~16%, respectively). Copyright

  3. Applications of sliding mode control in science and engineering

    CERN Document Server

    Lien, Chang-Hua

    2017-01-01

    Gathering 20 chapters contributed by respected experts, this book reports on the latest advances in and applications of sliding mode control in science and engineering. The respective chapters address applications of sliding mode control in the broad areas of chaos theory, robotics, electrical engineering, physics, chemical engineering, memristors, mechanical engineering, environmental engineering, finance, and biology. Special emphasis has been given to papers that offer practical solutions, and which examine design and modeling involving new types of sliding mode control such as higher order sliding mode control, terminal sliding mode control, super-twisting sliding mode control, and integral sliding mode control. This book serves as a unique reference guide to sliding mode control and its recent applications for graduate students and researchers with a basic knowledge of electrical and control systems engineering.

  4. High Level Control Applications for SOLEIL Commissioning and Operation

    CERN Document Server

    Nadolski, Laurent S; Ho, Katy; Leclercq, Nicolas; Ounsy, Majid; Petit, Sylvain

    2005-01-01

    The SOLEIL control system, namely TANGO developed in collaboration with ESRF, is now mature and stable. TANGO has also been chosen now by several other laboratories. High-level control applications implemented in the control room for the storage ring, the two transfer lines, and the booster will be described in this paper. Three kinds of tools for commissioning are used. First the generic TANGO tools (alarms, simple graphical control applications), which allow us to control in a simple way any TANGO Device Server. Secondly a Matlab Middle Layer (adapted from ALS and SPEAR3): Matlab is fully interconnected with TANGO; it is used primarily for writing Physics control applications. Finally Globalscreen, a commercial SCADA software devoted for building operation applications has been selected (panels for controlling or displaying setpoint, readback values, status of equipments). In addition an overview of the historical and short-term databases for the accelerators will be given. They have been developed in house...

  5. Wetting of a partially immersed compliant rod

    Science.gov (United States)

    Hui, Chung-Yuen; Jagota, Anand

    2016-11-01

    The force on a solid rod partially immersed in a liquid is commonly used to determine the liquid-vapor surface tension by equating the measured force required to remove the rod from the liquid to the vertical component of the liquid-vapor surface tension. Here, we study how this process is affected when the rod is compliant. For equilibrium, we enforce force and configurational energy balance, including contributions from elastic energy. We show that, in general, the contact angle does not equal that given by Young's equation. If surface stresses are tensile, the strain in the immersed part of the rod is found to be compressive and to depend only on the solid-liquid surface stress. The strain in the dry part of the rod can be either tensile or compressive, depending on a combination of parameters that we identify. We also provide results for compliant plates partially immersed in a liquid under plane strain and plane stress. Our results can be used to extract solid surface stresses from such experiments.

  6. The application of intelligent process control to space based systems

    Science.gov (United States)

    Wakefield, G. Steve

    1990-01-01

    The application of Artificial Intelligence to electronic and process control can help attain the autonomy and safety requirements of manned space systems. An overview of documented applications within various industries is presented. The development process is discussed along with associated issues for implementing an intelligence process control system.

  7. Embedded Fuzzy Controller for Industrial Applications

    OpenAIRE

    Ferenc Farkas; Sándor Halász

    2006-01-01

    The concept of the fuzzy logic makes feasible the creation of fuzzy controllerswith low cost 16 bit microcontroller having the same performance as of controllers realizedwith more expensive Digital Signal Processor (DSP). In this article the implementation ofsuch a fuzzy controller is proposed for 16 bit microcontroller with fast fuzzyficationinference-defuzzyfication algorithm. Because the microcontroller receives information fromthe process via Analog-Digital Converter(s) and controls the p...

  8. Bent Telescopic Rods in Patients With Osteogenesis Imperfecta.

    Science.gov (United States)

    Lee, R Jay; Paloski, Michael D; Sponseller, Paul D; Leet, Arabella I

    2016-09-01

    Telescopic rods require alignment of 2 rods to enable lengthening. A telescopic rod converts functionally into a solid rod if either rod bends, preventing proper engagement. Our goal was to characterize implant bending as a mode of failure of telescopic rods used in the treatment of osteogenesis imperfecta in children. We conducted a retrospective review of our osteogenesis imperfecta database for patients treated with intramedullary telescopic rods at our institution from 1992 through 2010 and identified 12 patients with bent rods. The 6 boys and 6 girls had an average age at the time of initial surgery of 3.1 years (range, 1.8 to 8.3 y) and a total of 51 telescoping rods. Clinic notes, operative reports, and radiographs were reviewed. The rods were analyzed for amount of lengthening, characteristics of bending, presence of cut out, or disengagement from an anchor point. Bends in the rods were characterized by their location on the implant component. The bent and straight rods were compared. Data were analyzed with the Mann-Whitney test (statistical significance set at P≤0.05). Of the 51 telescoping rods, 17 constructs (33%) bent. The average interval between surgery and rod bending was 4.0 years (range, 0.9 to 8.2 y). Before bending, 11 of 17 telescoping rods had routine follow-up radiographs for review. In 10 of the rods, bending was present when early signs of rod failure were first detected. Rod bending did not seem to be related to rod size. There was no area on the rod itself that seemed more susceptible to bending. Rod bending can be an early sign of impending rod failure. When rod bending is first noted, it may predispose the rod to other subsequent failures such as loss of proximal and distal fixation and cut out. Rod bending should be viewed as an indicator for closer monitoring of the patient and discussions regarding future need for rod exchange. Level III-retrospective review.

  9. Color dissociation artifacts in double Maddox rod cyclodeviation testing.

    Science.gov (United States)

    Simons, K; Arnoldi, K; Brown, M H

    1994-12-01

    The double Maddox rod test, based on a red Maddox rod in front of one eye and a clear Maddox rod in front of the other, is used to measure cyclodeviation, typically in patients with superior oblique muscle pareses. Discrepant results between the double Maddox rod test and other torsion measures, and reports of "paradoxic" cyclodeviation in the normal eye of some patients with superior oblique paresis, suggest the two-color format of the double Maddox rod test may produce artifactual torsion measures. Forty patients with superior oblique paresis were tested twice using the double Maddox rod test, reversing the red and white Maddox rods between eyes for the second test, and 18 were tested further with same-color red or clear Maddox rods in front of both eyes. With the standard double Maddox rod test, 33 (83%) of 40 patients localized their cyclodeviation to the eye viewing through the red Maddox rod, irrespective of laterality of the paresis or fixation preference. In all 33 patients, laterality of the perceived torsion changed between eyes when testing was repeated with red and white Maddox rods interchanged between eyes. With same-color Maddox rods before both eyes, 17 (94%) of 18 patients localized extorsion to the paretic eye. There was 7.6:1 ratio of luminance transmission and a 1.6:1 ratio of grating spatial frequency bandpass in the plano meridian between the clear and red Maddox rods, which appear to be responsible for the double Maddox rod test artifact. The traditional double Maddox rod test may produce artifactual cyclodeviation measurements. An alternative version of the test, based on same-color Maddox rods in front of both eyes, is proposed. The relatively high spatial frequency bandpass characteristics of the plano meridian of the Maddox rod (as high as 20/25 Snellen equivalent resolution through the clear Maddox rod) also suggests double Maddox rod testing should be conducted in a dark room to avoid biases from visual environment cues.

  10. Development of burnup dependent fuel rod model in COBRA-TF

    Science.gov (United States)

    Yilmaz, Mine Ozdemir

    predictions. After confirming that the new fuel thermal conductivity model in CTF worked and provided consistent results with FRAPTRAN predictions for a single fuel rod configuration, the same type of analysis was carried out for a bigger system which is the 4x4 PWR bundle consisting of 15 fuel pins and one control guide tube. Steady- state calculations at Hot Full Power (HFP) conditions for control guide tube out (unrodded) were performed using the 4x4 PWR array with CTF/TORT-TD coupled code system. Fuel centerline, surface and average temperatures predicted by CTF/TORT-TD with and without the new fuel thermal conductivity model were compared against CTF/TORT-TD/FRAPTRAN predictions to demonstrate the improvement in fuel centerline predictions when new model was used. In addition to that constant and CTF dynamic gap conductance model were used with the new thermal conductivity model to show the performance of the CTF dynamic gap conductance model and its impact on fuel centerline and surface temperatures. Finally, a Rod Ejection Accident (REA) scenario using the same 4x4 PWR array was run both at Hot Zero Power (HZP) and Hot Full Power (HFP) condition, starting at a position where half of the control rod is inserted. This scenario was run using CTF/TORT-TD coupled code system with and without the new fuel thermal conductivity model. The purpose of this transient analysis was to show the impact of thermal conductivity degradation (TCD) on feedback effects, specifically Doppler Reactivity Coefficient (DRC) and, eventually, total core reactivity.

  11. Robust control through signal constraints with application to predictive control

    NARCIS (Netherlands)

    de Vries, R.A.J.

    2006-01-01

    This thesis presents a novel approach to robust controller design. It describes how linear constraints can be derived on the output of an arbitrary controller, that guarantee robust bounded-input/bounded-output stability and asymptotic perfect tracking of the reference when the external signals

  12. Microcomputer controlled PWM inverter for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Gasso, A.; Prart, L.; Closas, L. (Barcelona Univ. (Spain))

    1988-09-01

    This paper covers the design of a microcomputer controlled two-branch PWM inverter bridge using power MOSFETs. In this system, the microcomputer simultaneously handles other functions of the photovoltaic system, making the associated circuitry simple. The work also discusses the limitations of this control system.

  13. Optimal control application to an Ebola model

    Directory of Open Access Journals (Sweden)

    Ebenezer Bonyah

    2016-04-01

    Full Text Available Ebola virus is a severe, frequently fatal illness, with a case fatality rate up to 90%. The outbreak of the disease has been acknowledged by World Health Organization as Public Health Emergency of International Concern. The threat of Ebola in West Africa is still a major setback to the socioeconomic development. Optimal control theory is applied to a system of ordinary differential equations which is modeling Ebola infection through three different routes including contact between humans and a dead body. In an attempt to reduce infection in susceptible population, a preventive control is put in the form of education and campaign and two treatment controls are applied to infected and late-stage infected (super human population. The Pontryagins maximum principle is employed to characterize optimality control, which is then solved numerically. It is observed that time optimal control is existed in the model. The activation of each control showed a positive reduction of infection. The overall effect of activation of all the controls simultaneously reduced the effort required for the reduction of the infection quickly. The obtained results present a good framework for planning and designing cost-effective strategies for good interventions in dealing with Ebola disease. It is established that in order to reduce Ebola threat all the three controls must be taken into consideration concurrently.

  14. Electro-Optic Effects in Colloidal Dispersion of Metal Nano-Rods in Dielectric Fluid

    Directory of Open Access Journals (Sweden)

    Oleg D. Lavrentovich

    2011-02-01

    Full Text Available In modern transformation optics, one explores metamaterials with properties that vary from point to point in space and time, suitable for application in devices such as an “optical invisibility cloak” and an “optical black hole”. We propose an approach to construct spatially varying and switchable metamaterials that are based on colloidal dispersions of metal nano-rods (NRs in dielectric fluids, in which dielectrophoretic forces, originating in the electric field gradients, create spatially varying configurations of aligned NRs. The electric field controls orientation and concentration of NRs and thus modulates the optical properties of the medium. Using gold (Au NRs dispersed in toluene, we demonstrate electrically induced change in refractive index on the order of 0.1.

  15. High power breakdown testing of a photonic band-gap accelerator structure with elliptical rods

    Directory of Open Access Journals (Sweden)

    Brian J. Munroe

    2013-01-01

    Full Text Available An improved single-cell photonic band-gap (PBG structure with an inner row of elliptical rods (PBG-E was tested with high power at a 60 Hz repetition rate at X-band (11.424 GHz, achieving a gradient of 128  MV/m at a breakdown probability of 3.6×10^{-3} per pulse per meter at a pulse length of 150 ns. The tested standing-wave structure was a single high-gradient cell with an inner row of elliptical rods and an outer row of round rods; the elliptical rods reduce the peak surface magnetic field by 20% and reduce the temperature rise of the rods during the pulse by several tens of degrees, while maintaining good damping and suppression of high order modes. When compared with a single-cell standing-wave undamped disk-loaded waveguide structure with the same iris geometry under test at the same conditions, the PBG-E structure yielded the same breakdown rate within measurement error. The PBG-E structure showed a greatly reduced breakdown rate compared with earlier tests of a PBG structure with round rods, presumably due to the reduced magnetic fields at the elliptical rods vs the fields at the round rods, as well as use of an improved testing methodology. A post-testing autopsy of the PBG-E structure showed some damage on the surfaces exposed to the highest surface magnetic and electric fields. Despite these changes in surface appearance, no significant change in the breakdown rate was observed in testing. These results demonstrate that PBG structures, when designed with reduced surface magnetic fields and operated to avoid extremely high pulsed heating, can operate at breakdown probabilities comparable to undamped disk-loaded waveguide structures and are thus viable for high-gradient accelerator applications.

  16. Polyetheretherketone (PEEK) Rods in Lumbar Spine Degenerative Disease: A Case Series.

    Science.gov (United States)

    Ormond, D Ryan; Albert, Ladislau; Das, Kaushik

    2016-08-01

    Retrospective case series. The purpose of our study was to retrospectively review the results of posterior lumbar fusion using polyetheretherketone (PEEK) rods. Pedicle screw and rod instrumentation has become the preferred technique for performing stabilization and fusion in the lumbar spine for degenerative disease. Rigid fixation with titanium rods leads to high fusion rates, but may also contribute to stress shielding and adjacent segment degeneration (ASD). Thus, some have advocated using semirigid rods made of PEEK. Although the biomechanical properties of PEEK rods have shown improved stress-shielding characteristics and anterior load-sharing properties, there are very few clinical studies evaluating their application in the lumbar spine. We evaluated a retrospective cohort of 42 patients who underwent posterior lumbar fusion from 2007 to 2009 for the treatment of lumbar spine degenerative disease using PEEK rods. Reoperation rate was the primary outcome evaluated. Fusion rate was also evaluated. Eight of the 42 patients with PEEK rods required reoperation. Reasons for reoperation mainly included ASD (5/8) and nonunion with cage migration (3/8). Radiographically, documented fusion rate was 86%. Mean follow-up was 31.4 months. No statistical differences were found in fusion rates or reoperation between age above 55 years and younger than 55 years (P=1.00), male and female (P=0.110), single or multilevel fusion (P=0.67), and fusion with and without an interbody graft (P=0.69). Smokers showed a trend towards increased risk of reoperation for ASD or instrumentation failure (P=0.056). PEEK rods demonstrate a similar fusion and reoperation rate in comparison to other instrumentation modalities in the treatment of degenerative lumbar spine disease.

  17. Breaking of rod-shaped model material during compression

    Directory of Open Access Journals (Sweden)

    Lukas Kulaviak

    2017-01-01

    Full Text Available The breakage of a model anisometric dry granular material caused by uniaxial compression was studied. The bed of uniform rod-like pasta particles (8 mm long, aspect ratio 1:8 was compressed (Gamlen Tablet Press and their size distribution was measured after each run (Dynamic Image Analysing. The compression dynamics was recorded and the effect of several parameters was tested (rate of compression, volume of granular bed, pressure magnitude and mode of application. Besides the experiments, numerical modelling of the compressed breakable material was performed as well, employing the DEM approach (Discrete Element Method. The comparison between the data and the model looks promising.

  18. Breaking of rod-shaped model material during compression

    Science.gov (United States)

    Lukas, Kulaviak; Vera, Penkavova; Marek, Ruzicka; Miroslav, Puncochar; Petr, Zamostny; Zdenek, Grof; Frantisek, Stepanek; Marek, Schongut; Jaromir, Havlica

    2017-06-01

    The breakage of a model anisometric dry granular material caused by uniaxial compression was studied. The bed of uniform rod-like pasta particles (8 mm long, aspect ratio 1:8) was compressed (Gamlen Tablet Press) and their size distribution was measured after each run (Dynamic Image Analysing). The compression dynamics was recorded and the effect of several parameters was tested (rate of compression, volume of granular bed, pressure magnitude and mode of application). Besides the experiments, numerical modelling of the compressed breakable material was performed as well, employing the DEM approach (Discrete Element Method). The comparison between the data and the model looks promising.

  19. Electromechanical actuation for thrust vector control applications

    Science.gov (United States)

    Roth, Mary Ellen

    At present, actuation systems for the Thrust Vector Control (TVC) for launch vehicles are hydraulic systems. The Advanced Launch System (ALS), a joint initiative between NASA and the Air Force, is a launch vehicle that is designed to be cost effective, highly reliable and operationally efficient with a goal of reducing the cost per pound to orbit. As part of this initiative, an electromechanical actuation system is being developed as an attractive alternative to the hydraulic systems used today. NASA-Lewis is developing and demonstrating an Induction Motor Controller Actuation System with a 40 hp peak rating. The controller will integrate 20 kHz resonant link Power Management and Distribution (PMAD) technology and Pulse Population Modulation (PPM) techniques to implement Field Oriented Vector Control (FOVC) of a new advanced induction motor. Through PPM, multiphase variable frequency, variable voltage waveforms can be synthesized from the 20 kHz source. FOVC shows that varying both the voltage and frequency and their ratio (V/F), permits independent control of both torque and speed while operating at maximum efficiency at any point on the torque-speed curve. The driver and the FOVC will be microprocessor controlled. For increased system reliability, a Built-in Test (BITE) capability will be included. This involves introducing testability into the design of a system such that testing is calibrated and exercised during the design, manufacturing, maintenance and prelaunch activities. An actuator will be integrated with the motor controller for performance testing of the EMA TVC system. The design and fabrication of the motor controller is being done by General Dynamics Space Systems Division. The University of Wisconsin-Madison will assist in the design of the advanced induction motor and in the implementation of the FOVC theory. A 75 hp electronically controlled dynamometer will be used to test the motor controller in all four quadrants of operation using flight type

  20. Modeling nonlinear problems in the mechanics of strings and rods the role of the balance laws

    CERN Document Server

    O'Reilly, Oliver M

    2017-01-01

    This book presents theories of deformable elastic strings and rods and their application to broad classes of problems. Readers will gain insights into the formulation and analysis of models for mechanical and biological systems. Emphasis is placed on how the balance laws interplay with constitutive relations to form a set of governing equations. For certain classes of problems, it is shown how a balance of material momentum can play a key role in forming the equations of motion. The first half of the book is devoted to the purely mechanical theory of a string and its applications. The second half of the book is devoted to rod theories, including Euler’s theory of the elastica, Kirchhoff ’s theory of an elastic rod, and a range of Cosserat rod theories. A variety of classic and recent applications of these rod theories are examined. Two supplemental chapters, the first on continuum mechanics of three-dimensional continua and the second on methods from variational calculus, are included to provide relevant ...

  1. Quantitative Robust Control Engineering: Theory and Applications

    Science.gov (United States)

    2006-09-01

    to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data...the D tank as a dashed line [mg/l] and the control input IR(t) is shown as a solid line [ per unit of the influent flow rate] with the G22(z...1992). Discrete quantitative feedback technique, Capítulo 16 en el libro : Digital Control Systems: theory, hardware, software, 2ª edicion. McGraw

  2. An in vitro biomechanical comparison of single-rod, dual-rod, and dual-rod with transverse connector in anterior thoracolumbar instrumentation.

    Science.gov (United States)

    Reddy, Chandan G; Magnetta, Michael; Dahdaleh, Nader S; Demmer, Matthew; Iyamah, Kingsley Abode; Lim, Tae-Hong; Torner, James C; Hitchon, Patrick W

    2012-04-01

    After thoracolumbar corpectomy, standard anterolateral instrumentation may consist of dual rods with cross-connectors. However, when the vertebral bodies are small or involved with disease, only 1 rod may be possible. To compare the biomechanics of an in vitro L1 corpectomy model using 1 rod, 2 rods, or 2 rods with 2 cross-connectors. Eight fresh frozen human cadaveric spines were potted from T9 to L3. Pure moments of 1.5, 3, and 4.5 Nm were applied, and the motion of the spine was measured using 3 infrared cameras. Loads were applied in flexion and extension, right and left lateral bending, and right and left axial rotation. Each spine was first tested in the intact state. After performing an L1 corpectomy and replacement with a carbon fiber reinforced polymer cage, 3 constructs were tested: single rod (1R), dual rod (2R), and dual rod with 2 transverse connectors (CC). Analysis of variance suggests significant main effects of load (P < .0001), axis (P = .022), construct (P =.0019), and individual spine (P < .0001). Overall, the single-rod construct is significantly less rigid than the intact spine in axial rotation. There is no significant difference between the intact spine and either the dual-rod construct or the dual-rod cross-connector construct. In our in vitro model of anterior spinal stabilization after corpectomy and grafting, a single-rod construct is significantly less rigid than the intact spine. Addition of a second rod returns the rigidity of the spine to the intact state. A dual-rod cross-connector construct is significantly more rigid than a single-rod construct.

  3. Rod stiffness as a risk factor of proximal junctional kyphosis after adult spinal deformity surgery: comparative study between cobalt chrome multiple-rod constructs and titanium alloy two-rod constructs.

    Science.gov (United States)

    Han, Sanghyun; Hyun, Seung-Jae; Kim, Ki-Jeong; Jahng, Tae-Ahn; Lee, Subum; Rhim, Seung-Chul

    2017-07-01

    Little is known about the effect of rod stiffness as a risk factor of proximal junctional kyphosis (PJK) after adult spinal deformity (ASD) surgery. The aim of this study was to compare radiographic outcomes after the use of cobalt chrome multiple-rod constructs (CoCr MRCs) and titanium alloy two-rod constructs (Ti TRCs) for ASD surgery with a minimum 1-year follow-up. Retrospective case-control study in two institutes. We included 54 patients who underwent ASD surgery with fusion to the sacrum in two academic institutes between 2002 and 2015. Radiographic outcomes were measured on the standing lateral radiographs before surgery, 1 month postoperatively, and at ultimate follow-up. The outcome measures were composed of pre- and postoperative sagittal vertical axis (SVA), pre- and postoperative lumbar lordosis (LL), pre- and postoperative thoracic kyphosis (TK)+LL+pelvic incidence (PI), pre- and postoperative PI minus LL, level of uppermost instrumented vertebra (UIV), evaluation of fusion after surgery, the presence of PJK, and the occurrence of rod fracture. We reviewed the medical records of 54 patients who underwent ASD surgery. Of these, 20 patients had CoCr MRC and 34 patients had Ti TRC. Baseline data and radiographic measurements were compared between the two groups. The Mann-Whitney U test, the chi-square test, and the Fisher exact test were used to compare outcomes between the groups. The patients of the groups were similar in terms of age, gender, diagnosis, number of three-column osteotomy, levels fused, bone mineral density, preoperative TK, pre- and postoperative TK+LL+PI, SVA difference, LL change, pre- and postoperative PI minus LL, and location of UIV (upper or lower thoracic level). However, there were significant differences in the occurrence of PJK and rod breakage (PJK: CoCr MRC: 12 [60%] vs. Ti TRC: 9 [26.5%], p=.015; occurrence of rod breakage: CoCr MRC: 0 [0%] vs. Ti TRC: 11 [32.4%], p=.004). The time of PJK was less than 12 months after

  4. Recent advances in electrical engineering and control applications

    CERN Document Server

    Bououden, Sofiane; Zelinka, Ivan

    2017-01-01

    This book of proceedings includes papers presenting the state of art in electrical engineering and control theory as well as their applications. The topics focus on classical as well as modern methods for modeling, control, identification and simulation of complex systems with applications in science and engineering. The papers were selected from the hottest topic areas, such as control and systems engineering, renewable energy, faults diagnosis—faults tolerant control, large-scale systems, fractional order systems, unconventional algorithms in control engineering, signals and communications. The control and design of complex systems dynamics, analysis and modeling of its behavior and structure is vitally important in engineering, economics and in science generally science today. Examples of such systems can be seen in the world around us and are a part of our everyday life. Application of modern methods for control, electronics, signal processing and more can be found in our mobile phones, car engines, hom...

  5. The application of mean control chart in managing industrial processes

    Directory of Open Access Journals (Sweden)

    Papić-Blagojević Nataša

    2013-01-01

    Full Text Available Along with the advent of mass production comes the problem of monitoring and maintaining the quality of the product, which stressed the need for the application of selected statistical and mathematical methods in the control process. The main objective of applying the methods of statistical control is continuous quality improvement through permanent monitoring of the process in order to discover the causes of errors. Shewart charts are the most popular method of statistical process control, which performs separation of controlled and uncontrolled variations along with detection of increased variations. This paper presents the example of Shewart mean control chart with application in managing industrial process.

  6. Function and application of isotope controlled materials

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Koichi; Suzuki, Hiroshi; Araki, Hiroshi; Fujita, Mitsutane; Hirano, Toshiyuki; Numazawa, Takenori; Noda, Tetsuji [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan)

    2000-02-01

    As large amounts of silicone isotopes were separated in previous research, we tried to develop function of isotope controlled materials. Molecular vibration excitation control to control laser wavelength, physical properties of isotope control materials and nuclear transformation function were studied. A gas circulation system for isotope laser development was manufactured. When a part of {sup 16}O in CO{sub 2} were changed by {sup 18}O, the stretching mode of CO{sub 2} became unsymmetrical mode. P17 and P19 of laser oscillation were observed. They are odd lines that have never been observed. SiF{sub 4} and Si{sub 2}F{sub 6} were decomposed by plasma CVD method. About 28% Si crystal was obtained by controlling the reaction temperature at about 350 to 450degC. Homogeneous P single crystal(100) with 10 mm diameter was obtained. Thermal conductivity of B single crystal with {sup 10}B showed 1.5 times as much as that of natural components. Calculation of displacement damages, change of components, induced radioactivity and decay heat were improved by arrangement of simulation code. (S.Y.)

  7. Labview Application For A Vehicle Control

    Directory of Open Access Journals (Sweden)

    Douglas Paladine Vieira

    2002-01-01

    Full Text Available This article deals with the construction of a vehicle driven by electric motors and that is automated, that is, that can move anywhere without human intervention. The control was done using the software Labview, with data acquisition and generation of control signs. The vehicle has an infrared sensors system that indicates the existence of an obstacle ahead the vehicle, informing it that it should stop and bypass the obstacle. The program is the responsible for the engine control, making it possible for the prototype to run and bypass the objects that block its way. The possibility of remote-controlling a vehicle is very important is risky situations for human beings, for example in radioactive places. The main advantage of this system is the total flexibility for making alterations in the control software, without being necessary to touch the physical part of the prototype. The conclusion of this work is that the system is efficient and able to move in a room with objects without touching them.

  8. Optimization and Control of Bilinear Systems Theory, Algorithms, and Applications

    CERN Document Server

    Pardalos, Panos M

    2008-01-01

    Covers developments in bilinear systems theory Focuses on the control of open physical processes functioning in a non-equilibrium mode Emphasis is on three primary disciplines: modern differential geometry, control of dynamical systems, and optimization theory Includes applications to the fields of quantum and molecular computing, control of physical processes, biophysics, superconducting magnetism, and physical information science

  9. 76 FR 77253 - Importer of Controlled Substances; Notice of Application

    Science.gov (United States)

    2011-12-12

    ... applicants for registration to import a basic class of any controlled substance in schedule I or II are, and... manufacturer of a controlled substance in schedule I or II, and prior to issuing a regulation under 21 U.S.C...) to be registered as an importer of Remifentanil (9739), a basic class of controlled substance listed...

  10. GPR application to historical buildings structural control

    Science.gov (United States)

    Pettinelli, E.; Barone, P. M.; Mattei, E.; Di Matteo, A.

    2009-04-01

    Preservation of historical buildings requires particular care, as any intervention must conducted in a way which does not alter or damage the style, structure or contents of the edifice. In order to properly plan the restoration of a building, non-destructive techniques can be extensively used to detect structural elements and weaknesses. Ground Penetrating Radar is particularly well adapted to this type of work, as the method is non-invasive, rapid, and provides high resolution images of contrasting subsurface materials. In the present work we show three case-histories on three historical buildings - different in age, structure and geometry - in which GPR technique has been successfully used. To obtain 2D time slices of the investigated area, high frequency bistatic GPR (900 MHz and 1GHz antennas) was applied in each site, acquiring data along several parallel profiles. The first case presented here, is the GPR detection of the fractures and the internal lesions in the architrave of the Porticus Octaviae, a Roman building partially restored, located downtown Rome. The second case shows the application of the GPR to detect the internal structure of the floors above the vaulted ceilings that houses a series of 16th century frescos in the important Zuccari Palace, also located in Rome. Finally, the third case illustrates the application of GPR to reconstruct the geometry and the reinforcement structures of the floors and the inside walls of the Provincial Palace of Pescara, dated back to the Fascist age. These three examples show that GPR technique is a valid support which, in exhaustive way, can highlight the state of conservation of historical buildings. In particular, this technique can produce fundamental information for the restorers, in terms of location, dimension, and geometry of the internal lesions in the structure, helping them in developing the best possible protection plan for an historical building. REFERENCES Annan A.P.; 2004: Ground Penetrating Radar

  11. Advances in control system technology for aerospace applications

    CERN Document Server

    2016-01-01

    This book is devoted to Control System Technology applied to aerospace and covers the four disciplines Cognitive Engineering, Computer Science, Operations Research, and Servo-Mechanisms. This edited book follows a workshop held at the Georgia Institute of Technology in June 2012, where the today's most important aerospace challenges, including aerospace autonomy, safety-critical embedded software engineering, and modern air transportation were discussed over the course of two days of intense interactions among leading aerospace engineers and scientists. Its content provide a snapshot of today's aerospace control research and its future, including Autonomy in space applications, Control in space applications, Autonomy in aeronautical applications, Air transportation, and Safety-critical software engineering.

  12. Different control applications on a vehicle using fuzzy logic control

    Indian Academy of Sciences (India)

    ksf and ksr are front and rear suspension spring constants; ktf and ktr are the stiffness of front and rear wheels; cf and cr are front and rear suspension damping ..... Rao M V C, Prahlad V 1997 A tunable fuzzy logic controller for vehicle active suspension systems. Fuzzy Sets and Systems, 85: 11–21. Sakman L E, Guclu R, ...

  13. Locus of Control and Performance: Widening Applicabilities

    Science.gov (United States)

    Manichander, T.

    2014-01-01

    In an attempt to explain the evidence which indicates that internal perception of control is positively related to academic achievement, this paper suggests that mediating motivational and cognitive reactions, which differentiate internals from externals, may account for this relationship. Furthermore, on the basis of data which suggest that the…

  14. Oligo(naphthylene–ethynylene) Molecular Rods

    DEFF Research Database (Denmark)

    Cramer, Jacob Roland; Ning, Yanxiao; Shen, Cai

    2013-01-01

    of palladium-catalyzed Sonogashira reactions between naphthyl halides and acetylenes. The triazene functionality was used as a protected iodine precursor to allow linear extension of the molecular rods during the synthe-ses. The carboxylic acid groups in the target molecules were protected as esters during...

  15. Modeling and simulation performance of sucker rod beam pump

    Energy Technology Data Exchange (ETDEWEB)

    Aditsania, Annisa, E-mail: annisaaditsania@gmail.com [Department of Computational Sciences, Institut Teknologi Bandung (Indonesia); Rahmawati, Silvy Dewi, E-mail: silvyarahmawati@gmail.com; Sukarno, Pudjo, E-mail: psukarno@gmail.com [Department of Petroleum Engineering, Institut Teknologi Bandung (Indonesia); Soewono, Edy, E-mail: esoewono@math.itb.ac.id [Department of Mathematics, Institut Teknologi Bandung (Indonesia)

    2015-09-30

    Artificial lift is a mechanism to lift hydrocarbon, generally petroleum, from a well to surface. This is used in the case that the natural pressure from the reservoir has significantly decreased. Sucker rod beam pumping is a method of artificial lift. Sucker rod beam pump is modeled in this research as a function of geometry of the surface part, the size of sucker rod string, and fluid properties. Besides its length, sucker rod string also classified into tapered and un-tapered. At the beginning of this research, for easy modeling, the sucker rod string was assumed as un-tapered. The assumption proved non-realistic to use. Therefore, the tapered sucker rod string modeling needs building. The numerical solution of this sucker rod beam pump model is computed using finite difference method. The numerical result shows that the peak of polished rod load for sucker rod beam pump unit C-456-D-256-120, for non-tapered sucker rod string is 38504.2 lb, while for tapered rod string is 25723.3 lb. For that reason, to avoid the sucker rod string breaks due to the overload, the use of tapered sucker rod beam string is suggested in this research.

  16. Wireless Sensor/Actuator Network Design for Mobile Control Applications

    Directory of Open Access Journals (Sweden)

    Youxian Sung

    2007-10-01

    Full Text Available Wireless sensor/actuator networks (WSANs are emerging as a new generationof sensor networks. Serving as the backbone of control applications, WSANs will enablean unprecedented degree of distributed and mobile control. However, the unreliability ofwireless communications and the real-time requirements of control applications raise greatchallenges for WSAN design. With emphasis on the reliability issue, this paper presents anapplication-level design methodology for WSANs in mobile control applications. Thesolution is generic in that it is independent of the underlying platforms, environment,control system models, and controller design. To capture the link quality characteristics interms of packet loss rate, experiments are conducted on a real WSAN system. From theexperimental observations, a simple yet efficient method is proposed to deal withunpredictable packet loss on actuator nodes. Trace-based simulations give promisingresults, which demonstrate the effectiveness of the proposed approach.

  17. Mandatory Access Control applications to web hosting

    Science.gov (United States)

    Prandini, Marco; Faldella, Eugenio; Laschi, Roberto

    "Hosting" represents a commonplace solution for the low-cost implementation of web sites through the efficient sharing of the resources of a single server. The arising security problems, however, are not always easily dealt with under the Discretionary Access Control model implemented by traditional operating systems. More robust separation between the hosted sites, as well as more robust protection of the host system, can be attained by exploiting the features typical of Mandatory Access Control systems. Recently, these systems have recently been made available to the vast Linux community through projects like SELinux and grsecurity. This paper describes the architecture of a secure hosting server, integrating SELinux functionalities into the Apache/PHP platform, designed with the goal of increasing security without adding administrative burdens or impacting performance.

  18. Distributed population dynamics: Optimization and control applications

    OpenAIRE

    Barreiro-Gómez, Julián; Obando, Germán; Quijano Silva, Nicanor

    2017-01-01

    © 2017 IEEE. Personal use for this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to serves or lists, or reuse of any copyrighted component of this work in other works. Population dynamics have been widely used in the design of learning and control systems for networked enginee...

  19. Distributed population dynamics: Optimization and control applications

    OpenAIRE

    Barreiro-Gómez, Julian; Obando, Germán; Quijano, Nicanor

    2016-01-01

    © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Population dynamics have been widely used in the design of learning and control systems for networked engineer...

  20. Insights into the optical and anti-bacterial properties of biogenic PbSe quantum rods

    Directory of Open Access Journals (Sweden)

    Jaya Mary Jacob

    2016-07-01

    Full Text Available The detailed optical properties of lead selenide (PbSe quantum rods biosynthesized in marine Aspergillus terreus were apprehended theoretically using ab initio calculations based on the experimental absorption spectrum. These studies indicate that the absorption coefficient of the biosynthesized PbSe quantum rods increases linearly with incident photon energies. The variation of other optical constants like extinction coefficient, refractive index and reflectance was comparable to that of the chemically synthesized counterparts. Further, the high dielectric constant and remarkable fluorescence of the biogenic PbSe quantum rods pronounce their application in opto-electronic devices in the Near Infra-Red and Ultraviolet spectral regime. The biosynthesized PbSe quantum rods were also found to possess appreciable anti-bacterial activity against various gram positive and gram negative bacterial species thus enhancing the relevance of the same for practical utility. Based on these results it can be concluded that biogenic PbSe quantum rods can be envisaged as potential candidates for bio-imaging, bio-sensing and other photo-voltaic applications.

  1. A methodology for obtaining the control rod patterns in a BWR using genetic algorithms; Una metodologia para obtener los patrones de barras de control en un BWR usando algoritmos geneticos

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz S, J.J.; Montes T, J.L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Requena R, I. [Universidad de Granada, 18071 Granada (Spain)]. e-mail: jjortiz@nuclear.inin.mx

    2003-07-01

    In this work the GACRP system based on the genetic algorithms technique for the obtaining of the drivers of control bars in a BWR reactor is presented. This methodology was applied to a transition cycle and a one of balance of the Laguna Verde nuclear power station (CNLV). For each one of the studied cycles, it was executed the methodology with a fixed length of the cycle and it was compared the effective multiplication factor of neutrons at the end of the cycle that it is obtained with the proposed drivers of control bars and the multiplication factor of neutrons obtained by means of a Haling calculation. It was found that it is possible to extend several days the length of both cycles with regard to the one Haling calculation. (Author)

  2. A Robust Controller Structure for Pico-Satellite Applications

    DEFF Research Database (Denmark)

    Kragelund, Martin Nygaard; Green, Martin; Kristensen, Mads

    This paper describes the development of a robust controller structure for use in pico-satellite missions. The structure relies on unknown disturbance estimation and use of robust control theory to implement a system that is robust to both unmodeled disturbances and parameter uncertainties. As one...... possible application, a satellite mission with the purpose of monitoring shipping routes for oil spills has been considered. However, it is the aim of the control structure to be widely applicable and adaptable for a vide variety of pico-satellite missions. The robust control structure has been evaluated...

  3. 5th International Conference on Optimization and Control with Applications

    CERN Document Server

    Teo, Kok; Zhang, Yi

    2014-01-01

    This book presents advances in state-of-the-art solution methods and their applications to real life practical problems in optimization, control and operations research. Contributions from world-class experts in the field are collated here in two parts, dealing first with optimization and control theory and then with techniques and applications. Topics covered in the first part include control theory on infinite dimensional Banach spaces, history-dependent inclusion and linear programming complexity theory. Chapters also explore the use of approximations of Hamilton-Jacobi-Bellman inequality for solving periodic optimization problems and look at multi-objective semi-infinite optimization problems, and production planning problems.  In the second part, the authors address techniques and applications of optimization and control in a variety of disciplines, such as chaos synchronization, facial expression recognition and dynamic input-output economic models. Other applications considered here include image retr...

  4. LED Retrofit Kits, TLEDs, and Lighting Controls: An Application Guide

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-03-01

    This document provides guidance for retrofitting existing fluorescent troffers including the LED and associated control options available, the pro/cons and costs/benefits of each option, and agency specific requirements (where applicable).

  5. Approximate viability for nonlinear evolution inclusions with application to controllability

    Directory of Open Access Journals (Sweden)

    Omar Benniche

    2016-12-01

    Full Text Available We investigate approximate viability for a graph with respect to fully nonlinear quasi-autonomous evolution inclusions. As application, an approximate null controllability result is given.

  6. DSP applications in advanced, intelligent motion control: the future

    Energy Technology Data Exchange (ETDEWEB)

    Beierke, S. [Texas Instruments Deutschland GmBh, Freising (Germany); Vas, P. [Univ. of Aberdeen, Dept. of Engineering (United Kingdom)

    2000-08-01

    Recently there has been a rapid increase in the number of DSPs for various motion control applications. However, in the future, further significant increase is expected due to wider applications in existing and new areas (e.g. household appliances, automotive auxiliaries, micro-electromechanical systems, military applications, etc.). The present paper discusses the state-of-art Texas Instruments fixed point and floating point DSPs used in motion control applications and will also focus on future activities. Currently new chip technologies are being developed which involve copper interconnects, silicon-on-insulator wafers, insulators with- low dielectric constants, etc. It is expected that future single-chip DSPs for advanced intelligent motion control will have higher performance, reduced costs, simpler designs, will incorporate various sensors, different modules for optimised PWM generation, efficiency control, vector and direct torque control (sensorless and quasisensorless solutions as well), condition monitoring, selfcommissioning, artificial-intelligence-based control, etc. A manufacturer's task of implementing sensorless and/or quasisensorless torque control schemes for induction, synchronous and switched reluctance motor drives will be significantly reduced by the application of the newly developed DSPs. The paper will discuss these issues and will also show some implementation results in various sensorless (classical DTC; DTC with torque-ripple reduction schemes; vector) and quasisensorless ac drives (e.g. a vector controlled induction motor drive). (orig.)

  7. Application of Object-Based Industrial Controls for Cryogenics

    CERN Document Server

    Casas-Cubillos, J; Gomes, P; Pezzetti, M; Sicard, Claude Henri; Varas, F J

    2002-01-01

    The first application of the CERN Unified Industrial Control system (UNICOS) has been developed for the 1.8 K refrigerator at point 1.8 in mid-2001. This paper presents the engineering methods used for application development, in order to reach the objectives of maintainability and reusability, in the context of a development done by an external consortium of engineering firms. It will also review the lessons learned during this first development and the improvements planned for the next applications.

  8. Visual basic application in computer hardware control and data ...

    African Journals Online (AJOL)

    Speech Recognition Technology enables text acquisition via users' dictation and knowledge gain through system dictation. In this paper the application of speech recognition technology in hardware device control and data acquisition is experimented using Visual Basic and the Speech Application Programming Interface ...

  9. 77 FR 5847 - Manufacturer of Controlled Substances; Notice of Application

    Science.gov (United States)

    2012-02-06

    ... Enforcement Administration Manufacturer of Controlled Substances; Notice of Application Pursuant to Sec. 1301..., Siemens Healthcare Diagnostics Inc., 100 GBC Drive, Mail Stop 514, Newark, Delaware 19702, made application by renewal to the Drug Enforcement Administration (DEA) to be registered as a bulk manufacturer of...

  10. Porous tantalum rod implant is an effective and safe choice for early-stage femoral head necrosis: a meta-analysis of clinical trials.

    Science.gov (United States)

    Zhang, Yang; Li, Le; Shi, Zhan-jun; Wang, Jian; Li, Zhi-han

    2013-02-01

    Femoral head necrosis (FHN) is a debilitating disease which seriously affects the patients' quality of life, especially the young. The porous tantalum rod has the advantages of high volumetric porosity, low modulus of elasticity, and excellent osteoinduction, with exceptional biocompatibility and safety record in clinical application, which makes it an ideal choice for FHN patients. However, there has not been a systematic analysis for its efficacy and safety. This meta-analysis of six randomized controlled trials and controlled clinical trials with 256 participants was performed to investigate the efficacy and safety of porous tantalum rod, by means of comparing with vascularized or non-vascularized bone grafting. Porous tantalum has its advantages in functional evaluation of Harris Hip Score, with a significant lower incidence of femoral head collapse. The surgical blood loss is low and the operative time is short with no increase in complication rate. Our preliminary analysis provided that the porous tantalum rod was a less invasive method and was effective and well tolerant for early-stage FHN patients. Further specially designed clinical trials for long-term follow-up and socioeconomic assessment are needed before a final determination.

  11. Active noise control technique and its application on ships

    Directory of Open Access Journals (Sweden)

    CHEN Kean

    2017-08-01

    Full Text Available Due to the rapid development during past three decades, Active Noise Control(ANC has become a highly complementary noise control approach in comparison with traditional approaches, and has formed a complete system including basic theory, investigation approach, key techniques and system implementation. Meanwhile, substantial progress has been achieved in such fields as the practical application, industrialization development and commercial popularization of ANC, and this developed technique provides a practical and feasible choice for the active control of ship noise. In this review paper, its sound field analysis, system setup and key techniques are summarized, typical examples of ANC-based engineering applications including control of cabin noise and duct noise are briefly described, and a variety of forefronts and problems associated with the applications of ANC in ship noise control, such as active sound absorption, active sound insulation and smart acoustic structure, are subsequently discussed.

  12. Distributed Mode Filtering Rod Fiber Amplifier With Improved Mode Stability

    DEFF Research Database (Denmark)

    Laurila, Marko; Alkeskjold, Thomas Tanggaard; Broeng, Jes

    2012-01-01

    We report 216W of average output power from a photonic crystal rod fiber amplifier. We demonstrate 44% power improvement before onset of the mode instability by operating the rod fiber in a leaky guiding regime.......We report 216W of average output power from a photonic crystal rod fiber amplifier. We demonstrate 44% power improvement before onset of the mode instability by operating the rod fiber in a leaky guiding regime....

  13. ROD INTERNAL PRESSURE QUANTIFICATION AND DISTRIBUTION ANALYSIS USING FRAPCON

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Kostadin [Pennsylvania State University, University Park; Jessee, Matthew Anderson [ORNL

    2016-01-01

    The discharge rod internal pressure (RIP) and cladding hoop stress (CHS) distributions are quantified forWatts BarNuclearUnit 1 (WBN1) fuel rods by modeling core cycle design data, intercycle assembly movements, operation data (including modeling significant trips and downpowers), and as-built fuel enrichments and densities of each fuel rod in FRAPCON-3.5. An alternate model for the amount of helium released from zirconium diboride (ZrB2) integral fuel burnable absorber (IFBA) layers is derived and applied to FRAPCON output data to quantify the RIP and CHS for these fuel rods. SCALE/Polaris is used to quantify fuel rod-specific spectral quantities and the amount of gaseous fission products produced in the fuel for use in FRAPCON inputs. Fuel rods with ZrB2 IFBA layers (i.e., IFBA rods) are determined to have RIP predictions that are elevated when compared to fuel rod without IFBA layers (i.e., standard rods) despite the fact that IFBA rods often have reduced fill pressures and annular fuel blankets. Cumulative distribution functions (CDFs) are prepared from the distribution of RIP predictions for all standard and IFBA rods. The provided CDFs allow for the determination of the portion of WBN1 fuel rods that exceed a specified RIP limit. Lastly, improvements to the computational methodology of FRAPCON are proposed.

  14. Measurement of the Speed of Sound in a Metal Rod.

    Science.gov (United States)

    Mak, Se-yuen; Ng, Yee-kong; Wu, Kam-wah

    2000-01-01

    Suggests two improved methods to measure the speed of sound in a metal rod. One employs a fast timer to measure the time required for a compression pulse to travel along the rod from end to end, and a second uses a microphone to measure the frequency of the fundamental mode of a freely suspending singing rod. (Author/ASK)

  15. 77 FR 1504 - Stainless Steel Wire Rod From India

    Science.gov (United States)

    2012-01-10

    ... COMMISSION Stainless Steel Wire Rod From India Determination On the basis of the record \\1\\ developed in the... antidumping duty order on stainless steel wire rod From India would be likely to lead to continuation or... contained in USITC Publication 4300 (January 2012), entitled Stainless Steel Wire Rod From India...

  16. Controlled Vocabulary Service Application for Environmental Data Store

    Science.gov (United States)

    Ji, P.; Piasecki, M.; Lovell, R.

    2013-12-01

    In this paper we present a controlled vocabulary service application for Environmental Data Store (EDS). The purpose for such application is to help researchers and investigators to archive, manage, share, search, and retrieve data efficiently in EDS. The Simple Knowledge Organization System (SKOS) is used in the application for the representation of the controlled vocabularies coming from EDS. The controlled vocabularies of EDS are created by collecting, comparing, choosing and merging controlled vocabularies, taxonomies and ontologies widely used and recognized in geoscience/environmental informatics community, such as Environment ontology (EnvO), Semantic Web for Earth and Environmental Terminology (SWEET) ontology, CUAHSI Hydrologic Ontology and ODM Controlled Vocabulary, National Environmental Methods Index (NEMI), National Water Information System (NWIS) codes, EPSG Geodetic Parameter Data Set, WQX domain value etc. TemaTres, an open-source, web -based thesaurus management package is employed and extended to create and manage controlled vocabularies of EDS in the application. TemaTresView and VisualVocabulary that work well with TemaTres, are also integrated in the application to provide tree view and graphical view of the structure of vocabularies. The Open Source Edition of Virtuoso Universal Server is set up to provide a Web interface to make SPARQL queries against controlled vocabularies hosted on the Environmental Data Store. The replicas of some of the key vocabularies commonly used in the community, are also maintained as part of the application, such as General Multilingual Environmental Thesaurus (GEMET), NetCDF Climate and Forecast (CF) Standard Names, etc.. The application has now been deployed as an elementary and experimental prototype that provides management, search and download controlled vocabularies of EDS under SKOS framework.

  17. Implementing a genomic data management system using iRODS in the Wellcome Trust Sanger Institute

    Directory of Open Access Journals (Sweden)

    Sale Kevin

    2011-09-01

    Full Text Available Abstract Background Increasingly large amounts of DNA sequencing data are being generated within the Wellcome Trust Sanger Institute (WTSI. The traditional file system struggles to handle these increasing amounts of sequence data. A good data management system therefore needs to be implemented and integrated into the current WTSI infrastructure. Such a system enables good management of the IT infrastructure of the sequencing pipeline and allows biologists to track their data. Results We have chosen a data grid system, iRODS (Rule-Oriented Data management systems, to act as the data management system for the WTSI. iRODS provides a rule-based system management approach which makes data replication much easier and provides extra data protection. Unlike the metadata provided by traditional file systems, the metadata system of iRODS is comprehensive and allows users to customize their own application level metadata. Users and IT experts in the WTSI can then query the metadata to find and track data. The aim of this paper is to describe how we designed and used (from both system and user viewpoints iRODS as a data management system. Details are given about the problems faced and the solutions found when iRODS was implemented. A simple use case describing how users within the WTSI use iRODS is also introduced. Conclusions iRODS has been implemented and works as the production system for the sequencing pipeline of the WTSI. Both biologists and IT experts can now track and manage data, which could not previously be achieved. This novel approach allows biologists to define their own metadata and query the genomic data using those metadata.

  18. 75 FR 36680 - Importer of Controlled Substances; Notice of Application

    Science.gov (United States)

    2010-06-28

    ... basic classes of controlled substances listed in schedule II: Drug Schedule Raw Opium (9600) II... Register on September 23, 1975, (40 FR 43745), all applicants for registration to import a basic class of any controlled substances in schedule I or II are, and will continue to be, required to demonstrate to...

  19. Fast-acting nuclear reactor control device

    Science.gov (United States)

    Kotlyar, Oleg M.; West, Phillip B.

    1993-01-01

    A fast-acting nuclear reactor control device for moving and positioning a fety control rod to desired positions within the core of the reactor between a run position in which the safety control rod is outside the reactor core, and a shutdown position in which the rod is fully inserted in the reactor core. The device employs a hydraulic pump/motor, an electric gear motor, and solenoid valve to drive the safety control rod into the reactor core through the entire stroke of the safety control rod. An overrunning clutch allows the safety control rod to freely travel toward a safe position in the event of a partial drive system failure.

  20. On the applications of statistical process control in health care.

    Science.gov (United States)

    Adeoti, O A

    2009-01-01

    Statistical Process Control (SPC), a sub-area of Statistical Quality Control (SQC) has been widely used in the manufacturing industry for a long time to monitor and improve processes. However, the use of SPC in other application areas in particular healthcare has been met with resistance due to lack of evidence or lack of conviction regarding their power of utility. Literature and computer programmes (Medline and PsychoInfo databases) were searched for relevant information. This paper provides an overview of SPC, and its primary tool- the control chart, the challenges and the benefits of the application of SPC as tool for health care improvement.

  1. Fuzzy logic applications to expert systems and control

    Science.gov (United States)

    Lea, Robert N.; Jani, Yashvant

    1991-01-01

    A considerable amount of work on the development of fuzzy logic algorithms and application to space related control problems has been done at the Johnson Space Center (JSC) over the past few years. Particularly, guidance control systems for space vehicles during proximity operations, learning systems utilizing neural networks, control of data processing during rendezvous navigation, collision avoidance algorithms, camera tracking controllers, and tether controllers have been developed utilizing fuzzy logic technology. Several other areas in which fuzzy sets and related concepts are being considered at JSC are diagnostic systems, control of robot arms, pattern recognition, and image processing. It has become evident, based on the commercial applications of fuzzy technology in Japan and China during the last few years, that this technology should be exploited by the government as well as private industry for energy savings.

  2. Numerical Simulation and Experimental Validation of an Integrated Sleeve-Wedge Anchorage for CFRP Rods

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Smith, Scott T.; Täljsten, Björn

    2011-01-01

    The tensioning of carbon fibre-reinforced polymer (CFRP) rods for prestressed concrete applications or post-tensioning repair and strengthening has met with mixed success. This is primarily due to limitations inherent in the use of traditional wedge anchors typically used for steel tendons...

  3. Control charts 101: a guide to health care applications.

    Science.gov (United States)

    Amin, S G

    2001-01-01

    A control chart can be an effective way to display process data over time. It can differentiate common cause variation from special cause variation through the application of several probability-based interpretation rules. In addition, a control chart can be helpful in evaluating the effectiveness of a change. There are numerous types of control charts, and this tutorial was developed to guide the user through the selection process.

  4. Computer simulation of the behaviour and performance of a CANDU fuel rod

    Energy Technology Data Exchange (ETDEWEB)

    Marino, A.C. [Comison Nacional de Energia Atomica (Argentina)

    1997-07-01

    At the Argentine Atomic Energy Commission (Comision Nacional de Energia Atomica, CNEA) the BACO code (for 'BArra COmbustible', fuel rod) was developed. It allows the simulation of the thermo-mechanical performance of a cylindrical fuel rod in a Pressurized Heavy Water Reactor (PHWR). The standard present version of the code (2.30), is a powerful tool for a relatively easy and complete evaluation of fuel behaviour predictions. Input parameters and, therefore, output ones may include statistical dispersion. As a demonstration of BACO capabilities we include a review of CANDU fuel applications, and the calculation and a parametric analysis of a characteristic CANDU fuel. (author)

  5. Procedure for improving temperature distribution via rods and columns -- B Pile

    Energy Technology Data Exchange (ETDEWEB)

    Menegus, R.L.

    1945-10-05

    Since the development of relationships between rod changes and temperature shifts, the temperature distribution of the B Pile has been improved as much as possible by shifting the rods. Certain unbalances have been found which can only be removed by improvement of the poison pattern. At present the maximum imperfection in the B Pile is 5% diagonal quadrupole unbalance. An estimate of the poison pattern needed to correct these imperfections is given herein. This poison pattern has been calculated as an example of application of the principles and is not intended as a recommendation.

  6. Lasing in self-assembled microcavities of CdSe/CdS core/shell colloidal quantum rods

    Science.gov (United States)

    Zavelani-Rossi, Margherita; Lupo, Maria Grazia; Krahne, Roman; Manna, Liberato; Lanzani, Guglielmo

    2010-06-01

    Colloidal semiconductor quantum rods have demonstrated many advantageous properties as light emitters such as high quantum yield, tunable emission wavelength, and polarized emission. This makes them an interesting optical gain material for laser applications. We report room-temperature gain lifetimes in core/shell CdSe/CdS quantum rods exceeding 300 ps, and show that the long gain lifetimes result from the significant reduction of Auger recombination in our quantum rods, even though the electrons are delocalized over the rod volume. We also fabricate devices by deposition of small droplets of quantum rod solution onto flat substrates. The evaporation dynamics of the droplets are governed by the coffee stain effect which leads to the formation of well defined micron-size stripes. These stripes consist of densely packed, laterally aligned quantum rods and provide optical feedback originating from the abrupt changes of refractive index at the stripe borders. We exploit the optical gain and the coffee stain mediated self-assembly and show that we can fabricate novel microlasers solely by deposition of droplets of quantum rod solutions on flat substrates.

  7. Rod Driven Frequency Entrainment and Resonance Phenomena

    Directory of Open Access Journals (Sweden)

    Christina Salchow

    2016-08-01

    Full Text Available A controversy exists on photic driving in the human visual cortex evoked by intermittent photic stimulation. Frequency entrainment and resonance phenomena are reported for frequencies higher than 12 Hz in some studies while missing in others. We hypothesized that this might be due to different experimental conditions, since both high and low intensity light stimulation were used. However, most studies do not report radiometric measurements, which makes it impossible to categorize the stimulation according to photopic, mesopic, and scotopic vision. Low intensity light stimulation might lead to scotopic vision, where rod perception dominates. In this study, we investigated photic driving for rod-dominated visual input under scotopic conditions. Twelve healthy volunteers were stimulated with low intensity light flashes at 20 stimulation frequencies, leading to rod activation only. The frequencies were multiples of the individual alpha frequency (α of each volunteer in the range from 0.40–2.30*α. 306-channel whole head magnetoencephalography recordings were analyzed in time, frequency, and spatiotemporal domains with the Topographic Matching Pursuit algorithm. We found resonance phenomena and frequency entrainment for stimulations at or close to the individual alpha frequency (0.90–1.10*α and half of the alpha frequency (0.40–0.55*α. No signs of resonance and frequency entrainment phenomena were revealed around 2.00*α. Instead, on-responses at the beginning and off-responses at the end of each stimulation train were observed for the first time in a photic driving experiment at frequencies of 1.30–2.30*α, indicating that the flicker fusion threshold was reached. All results, the resonance and entrainment as well as the fusion effects, provide evidence for rod-dominated photic driving in the visual cortex.

  8. Control of the neutronic and thermohydraulic conditions of power ramps in an irradiation loop for PWR fuel rod; Controle des conditions neutroniques et thermohydrauliques des rampes de puissance dans une boucle d`irradiation de combustibles de reacteur a eau pressurisee

    Energy Technology Data Exchange (ETDEWEB)

    Moulin, D.J.F.

    1993-09-10

    In order to study the power transients effects on PWR fuel rod clad, ramp tests in a pressurized water loop, are carried out at OSIRIS reactor. The present thesis deals with the on-line control of the device, during power ramp and conditioning irradiation. Based on a convolution-type resolution of the kinetics equations, a dynamic compensation of the Silver self-powered neutron detector was developed. With this method, the uncertainty of the ramp end-point is lower than 1%, thus it is very suited for monitoring both transient, as well as steady state conditions. Furthermore, a thermohydraulic model of the irradiation device is described: heat transfer equations, including gamma heating in materials, are solved to obtain temperatures and thermal fluxes of steady states. Results from the model and temperature measurements of the coolant are used together for fuel power determination, in real time. The clad external temperature profile is also calculated and displayed, to improve the irradiation monitoring. (author), 51 refs., 12 annexes, 66 figs.

  9. Wearable Device Control Platform Technology for Network Application Development

    Directory of Open Access Journals (Sweden)

    Heejung Kim

    2016-01-01

    Full Text Available Application development platform is the most important environment in IT industry. There are a variety of platforms. Although the native development enables application to optimize, various languages and software development kits need to be acquired according to the device. The coexistence of smart devices and platforms has rendered the native development approach time and cost consuming. Cross-platform development emerged as a response to these issues. These platforms generate applications for multiple devices based on web languages. Nevertheless, development requires additional implementation based on a native language because of the coverage and functions of supported application programming interfaces (APIs. Wearable devices have recently attracted considerable attention. These devices only support Bluetooth-based interdevice communication, thereby making communication and device control impossible beyond a certain range. We propose Network Application Agent (NetApp-Agent in order to overcome issues. NetApp-Agent based on the Cordova is a wearable device control platform for the development of network applications, controls input/output functions of smartphones and wearable/IoT through the Cordova and Native API, and enables device control and information exchange by external users by offering a self-defined API. We confirmed the efficiency of the proposed platform through experiments and a qualitative assessment of its implementation.

  10. A nonlinear theory for fibre-reinforced magneto-elastic rods

    Science.gov (United States)

    Ciambella, Jacopo; Favata, Antonino; Tomassetti, Giuseppe

    2018-01-01

    We derive a model for the finite motion of a fibre-reinforced magneto-elastic rod. The reinforcing particles are assumed weakly and uniformly magnetized, rigid and firmly embedded into the elastomeric matrix. We deduce closed-form expressions of the quasi-static motion of the rod in terms of the external magnetic field and of the body forces. The dependences of the motion on the shape of the inclusions, their orientation, their anisotropic magnetic properties and the Young modulus of the matrix are analysed and discussed. Two case studies are presented, in which the rod is used as an actuator suspended in a cantilever configuration. This work can foster new applications in the field of soft-actuators.

  11. Access Control of Web- and Java-Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.

    2013-01-01

    Cybersecurity has become a great concern as threats of service interruption, unauthorized access, stealing and altering of information, and spreading of viruses have become more prevalent and serious. Application layer access control of applications is a critical component in the overall security solution that also includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. An access control solution, based on an open-source access manager augmented with custom software components, was developed to provide protection to both Web-based and Javabased client and server applications. The DISA Security Service (DISA-SS) provides common access control capabilities for AMMOS software applications through a set of application programming interfaces (APIs) and network- accessible security services for authentication, single sign-on, authorization checking, and authorization policy management. The OpenAM access management technology designed for Web applications can be extended to meet the needs of Java thick clients and stand alone servers that are commonly used in the JPL AMMOS environment. The DISA-SS reusable components have greatly reduced the effort for each AMMOS subsystem to develop its own access control strategy. The novelty of this work is that it leverages an open-source access management product that was designed for Webbased applications to provide access control for Java thick clients and Java standalone servers. Thick clients and standalone servers are still commonly used in businesses and government, especially for applications that require rich graphical user interfaces and high-performance visualization that cannot be met by thin clients running on Web browsers

  12. Hardened plungers and piston rods for high-pressure compressors

    Energy Technology Data Exchange (ETDEWEB)

    1942-07-07

    This report was a summary of information on dimensions, materials, and operating conditions, as well as experience in the use of piston rods and plungers at Gelsenkirchen. The surface hardening of these parts and their resulting life and wear were of prime importance. Nitriding hardening was one of the best processes for the production of wearproof surfaces. Case hardening and autogeneous hardening had been found satisfactory. Heat hardening had been found to be a cheap process in many applications. Surfaces could be obtained by hard chrome plating which would have the same or higher wear resistance as nitriding and excel in the depth of hardness. However, the heat hardening alone produced hard layers which had sufficiently good properties for plungers and piston rods of the booster compressors, gas-circulation pumps, paste presses, compressors and possibly pressure-release machines. This plant possessed a hardening installation which offered the advantage of production of most of the required equipment right at the works. This was particularly important if a grinding machine was available. This arrangement had to be supplemented with a shaft furnace in which parts could be heated to remove stresses before and after machining. 5 tables.

  13. Complex systems and networks dynamics, controls and applications

    CERN Document Server

    Yu, Xinghuo; Chen, Guanrong; Yu, Wenwu

    2016-01-01

    This elementary book provides some state-of-the-art research results on broad disciplinary sciences on complex networks. It presents an in-depth study with detailed description of dynamics, controls and applications of complex networks. The contents of this book can be summarized as follows. First, the dynamics of complex networks, for example, the cluster dynamic analysis by using kernel spectral methods, community detection algorithms in bipartite networks, epidemiological modeling with demographics and epidemic spreading on multi-layer networks, are studied. Second, the controls of complex networks are investigated including topics like distributed finite-time cooperative control of multi-agent systems by applying homogenous-degree and Lyapunov methods, composite finite-time containment control for disturbed second-order multi-agent systems, fractional-order observer design of multi-agent systems, chaos control and anticontrol of complex systems via Parrondos game and many more. Third, the applications of ...

  14. Between a Map and a Data Rod

    Science.gov (United States)

    Teng, W. L.; Rui, H.; Strub, R. F.; Vollmer, B.

    2015-12-01

    A "Digital Divide" has long stood between how NASA and other satellite-derived data are typically archived (time-step arrays or "maps") and how hydrology and other point-time series oriented communities prefer to access those data. In essence, the desired method of data access is orthogonal to the way the data are archived. Our approach to bridging the Divide is part of a larger NASA-supported "data rods" project to enhance access to and use of NASA and other data by the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) Hydrologic Information System (HIS) and the larger hydrology community. Our main objective was to determine a way to reorganize data that is optimal for these communities. Two related objectives were to optimally reorganize data in a way that (1) is operational and fits in and leverages the existing Goddard Earth Sciences Data and Information Services Center (GES DISC) operational environment and (2) addresses the scaling up of data sets available as time series from those archived at the GES DISC to potentially include those from other Earth Observing System Data and Information System (EOSDIS) data archives. Through several prototype efforts and lessons learned, we arrived at a non-database solution that satisfied our objectives/constraints. We describe, in this presentation, how we implemented the operational production of pre-generated data rods and, considering the tradeoffs between length of time series (or number of time steps), resources needed, and performance, how we implemented the operational production of on-the-fly ("virtual") data rods. For the virtual data rods, we leveraged a number of existing resources, including the NASA Giovanni Cache and NetCDF Operators (NCO) and used data cubes processed in parallel. Our current benchmark performance for virtual generation of data rods is about a year's worth of time series for hourly data (~9,000 time steps) in ~90 seconds. Our approach is a specific

  15. Controllable deformation of salt water-filled carbon nanotubes using an electric field with application to molecular sieving

    Science.gov (United States)

    Ye, Hongfei; Zheng, Yonggang; Zhang, Zhongqiang; Zhang, Hongwu; Chen, Zhen

    2016-08-01

    Precisely controlling the deformation of carbon nanotubes (CNTs) has practical application in the development of nanoscale functional devices, although it is a challenging task. Here, we propose a novel method to guide the deformation of CNTs through filling them with salt water and applying an electric field. With the electric field along the axial direction, the height of CNTs is enlarged by the axial electric force due to the internal ions and polar water molecules. Under an electric field with two mutually orthogonal components, the transverse electric force could further induce the bending deformation of CNTs. Based on the classical rod and beam theories, two mechanical models are constructed to verify and quantitatively describe the relationships between the tension and bending deformations of CNTs and the electric field intensity. Moreover, by means of the electric field-driven tension behavior of CNTs, we design a stretchable molecular sieve to control the flow rate of mixed gas and collect a single high-purity gas. The present work opens up new avenues in the design and fabrication of nanoscale controlling units.

  16. On acoustic emission for damage detection and failure prediction in fiber reinforced polymer rods using pattern recognition analysis

    Science.gov (United States)

    Shateri, Mohammadhadi; Ghaib, Maha; Svecova, Dagmar; Thomson, Douglas

    2017-06-01

    Fiber reinforced polymer (FRP) rods are used for pre-stressing and reinforcing in civil engineering applications. Damage in FRP rods can lead to sudden brittle failure, therefore, a reliable method that provides indicators of damage progression and potential failure in FRP rods is highly desirable. Acoustic emission (AE) signal analysis has been used for damage detection and monitoring of FRP materials. In this study, a new AE event detection algorithm, utilizing the root mean square envelope of AE signal, is applied to AE data to isolate each AE event separately, even when AE events are nearly coincident. A fuzzy c-means (FCM) clustering algorithm is used to classify these isolated AE events into 3 clusters. Scanning electron microscopy images of FRP rod cross-sections also show 3 types of damage. The hypothesis in this study is that each cluster represents a damage mechanism. The number of events in each cluster is monitored versus the percent of the ultimate load. The ratio of the number of AE events in one of the FCM clusters to the number of AE events in another FCM cluster was useful for providing an indication of when the stress levels have reached the point where the loads may cause the FRP rod to fail. The results of applying this parameter to four FRP rods show a significant slope change (factor of 10) in this ratio at around 40% and 60% of the ultimate load for glass FRP rods and carbon FRP rods, respectively. This method may prove useful in damage progression and failure prediction of the FRP rods in prefabricated structures where pre-stressed FRP is used and in field monitoring of FRP materials.

  17. Indirect control of flexible demand for power system applications

    DEFF Research Database (Denmark)

    Sossan, Fabrizio

    This thesis addresses the topic of control of flexible demand to provide support to the operation of the electric power system. We focus on the indirect control approach, a framework that enables demand response by means of a consumption incentive signal. Initially, the concept of flexibility...... Flexhouse, a facility of DTU Elektro for testing demand side management strategies, as experimental site. In the latter case, we develop four applications where flexible demand is required to support power system operations. The applications are: integration of the operation of flexible demand...... and storage in the operation of the future power system, we develop a model predictive control strategy for a smart building with the objective of supplying iii space heating and providing regulating power to the grid according to a dynamic electricity price. We named this application energy replacement...

  18. Application of optical transmission in control power system

    Science.gov (United States)

    Kuźma, Adam; Zajkowski, Maciej

    2011-06-01

    The advantage of fiber optic data transmission systems is their insensitivity to electromagnetic radiation, in which the optical fiber. Some exemplary applications of fiber optic transmission in power electronics and electric drives which due to their specific job bring significant electromagnetic interference. Electrical signal wires are in an area of very strong electromagnetic field so that the transmission distortion may occur. The paper presents existing and possible applications of optical links using optical fibers, in the control of power systems.

  19. Application of multi-function display and control technology

    Science.gov (United States)

    Spiger, R. J.; Farrell, R. J.; Holcomb, G. A.

    1982-01-01

    The NASA orbiter spacecraft incorporates a complex array of systems, displays, and controls. The incorporation of discrete dedicated controls into a multifunction display and control system (MFDCS) offers the potential for savings in weight, power, panel space, and crew training time. Technology identified as applicable to a MFDCS is applied to the orbiter orbital maneuvering system (OMS) and the electrical power distribution and control system (EPDCS) to derive concepts for a MFDCS design. Several concepts of varying degrees of performance and complexity are discussed and a suggested concept for further development is presented in greater detail. Both the hardware and software aspects and the human factors considerations of the designs are included.

  20. Development of Plant Control Diagnosis Technology and Increasing Its Applications

    Science.gov (United States)

    Kugemoto, Hidekazu; Yoshimura, Satoshi; Hashizume, Satoru; Kageyama, Takashi; Yamamoto, Toru

    A plant control diagnosis technology was developed to improve the performance of plant-wide control and maintain high productivity of plants. The control performance diagnosis system containing this technology picks out the poor performance loop, analyzes the cause, and outputs the result on the Web page. Meanwhile, the PID tuning tool is used to tune extracted loops from the control performance diagnosis system. It has an advantage of tuning safely without process changes. These systems are powerful tools to do Kaizen (continuous improvement efforts) step by step, coordinating with the operator. This paper describes a practical technique regarding the diagnosis system and its industrial applications.

  1. Nanoporous Silicified Phospholipids and Application to Controlled Glycolic Acid Release

    Directory of Open Access Journals (Sweden)

    Kang SangHwa

    2008-01-01

    Full Text Available Abstract This work demonstrates the synthesis and characterization of novel nanoporous silicified phospholipid bilayers assembled inorganic powders. The materials are obtained by silicification process with silica precursor at the hydrophilic region of phospholipid bilayers. This process involves the co-assembly of a chemically active phospholipids bilayer within the ordered porosity of a silica matrix and holds promise as a novel application for controlled drug release or drug containers with a high level of specificity and throughput. The controlled release application of the synthesized materials was achieved to glycolic acid, and obtained a zero-order release pattern due to the nanoporosity.

  2. Neural network based adaptive output feedback control: Applications and improvements

    Science.gov (United States)

    Kutay, Ali Turker

    Application of recently developed neural network based adaptive output feedback controllers to a diverse range of problems both in simulations and experiments is investigated in this thesis. The purpose is to evaluate the theory behind the development of these controllers numerically and experimentally, identify the needs for further development in practical applications, and to conduct further research in directions that are identified to ultimately enhance applicability of adaptive controllers to real world problems. We mainly focus our attention on adaptive controllers that augment existing fixed gain controllers. A recently developed approach holds great potential for successful implementations on real world applications due to its applicability to systems with minimal information concerning the plant model and the existing controller. In this thesis the formulation is extended to the multi-input multi-output case for distributed control of interconnected systems and successfully tested on a formation flight wind tunnel experiment. The command hedging method is formulated for the approach to further broaden the class of systems it can address by including systems with input nonlinearities. Also a formulation is adopted that allows the approach to be applied to non-minimum phase systems for which non-minimum phase characteristics are modeled with sufficient accuracy and treated properly in the design of the existing controller. It is shown that the approach can also be applied to augment nonlinear controllers under certain conditions and an example is presented where the nonlinear guidance law of a spinning projectile is augmented. Simulation results on a high fidelity 6 degrees-of-freedom nonlinear simulation code are presented. The thesis also presents a preliminary adaptive controller design for closed loop flight control with active flow actuators. Behavior of such actuators in dynamic flight conditions is not known. To test the adaptive controller design in

  3. Application of statistical process control in healthcare improvement: systematic review.

    Science.gov (United States)

    Thor, Johan; Lundberg, Jonas; Ask, Jakob; Olsson, Jesper; Carli, Cheryl; Härenstam, Karin Pukk; Brommels, Mats

    2007-10-01

    To systematically review the literature regarding how statistical process control--with control charts as a core tool--has been applied to healthcare quality improvement, and to examine the benefits, limitations, barriers and facilitating factors related to such application. Original articles found in relevant databases, including Web of Science and Medline, covering the period 1966 to June 2004. From 311 articles, 57 empirical studies, published between 1990 and 2004, met the inclusion criteria. A standardised data abstraction form was used for extracting data relevant to the review questions, and the data were analysed thematically. Statistical process control was applied in a wide range of settings and specialties, at diverse levels of organisation and directly by patients, using 97 different variables. The review revealed 12 categories of benefits, 6 categories of limitations, 10 categories of barriers, and 23 factors that facilitate its application and all are fully referenced in this report. Statistical process control helped different actors manage change and improve healthcare processes. It also enabled patients with, for example asthma or diabetes mellitus, to manage their own health, and thus has therapeutic qualities. Its power hinges on correct and smart application, which is not necessarily a trivial task. This review catalogs 11 approaches to such smart application, including risk adjustment and data stratification. Statistical process control is a versatile tool which can help diverse stakeholders to manage change in healthcare and improve patients' health.

  4. Region based Brain Computer Interface for a home control application.

    Science.gov (United States)

    Akman Aydin, Eda; Bay, Omer Faruk; Guler, Inan

    2015-08-01

    Environment control is one of the important challenges for disabled people who suffer from neuromuscular diseases. Brain Computer Interface (BCI) provides a communication channel between the human brain and the environment without requiring any muscular activation. The most important expectation for a home control application is high accuracy and reliable control. Region-based paradigm is a stimulus paradigm based on oddball principle and requires selection of a target at two levels. This paper presents an application of region based paradigm for a smart home control application for people with neuromuscular diseases. In this study, a region based stimulus interface containing 49 commands was designed. Five non-disabled subjects were attended to the experiments. Offline analysis results of the experiments yielded 95% accuracy for five flashes. This result showed that region based paradigm can be used to select commands of a smart home control application with high accuracy in the low number of repetitions successfully. Furthermore, a statistically significant difference was not observed between the level accuracies.

  5. Casting technology for manufacturing metal rods from simulated metallic spent fuels

    Science.gov (United States)

    Leeand, Y. S.; Lee, D. B.; Kim, C. K.; Shin, Y. J.; Lee, J. H.

    2000-09-01

    A uranium metal rod 13.5 mm in diameter and 1,150 mm long was produced from simulated metallic spent fuels with advanced casting equipment using the directional-solidification method. A vacuum casting furnace equipped with a four-zone heater to prevent surface oxidation and the formation of surface shrinkage holes was designed. By controlling the axial temperature gradient of the casting furnace, deformation by the surface shrinkage phenomena was diminished, and a sound rod was manufactured. The cooling behavior of the molten uranium was analyzed using the computer software package MAGMAsoft.

  6. Model Oriented Application Generation for Industrial Control Systems

    CERN Document Server

    Copy, B; Blanco Vinuela, E; Fernandez Adiego, B; Nogueira Ferandes, R; Prieto Barreiro, I

    2011-01-01

    The CERN Unified Industrial Control Systems framework (UNICOS) is a software generation methodology and a collection of development tools that standardizes the design of industrial control applications [1]. A Software Factory, named the UNICOS Application Builder (UAB) [2], was introduced to ease extensibility and maintenance of the framework, introducing a stable metamodel, a set of platformindependent models and platformspecific configurations against which code generation plugins and configuration generation plugins can be written. Such plugins currently target PLC programming environments (Schneider and SIEMENS PLCs) as well as SIEMENS WinCC Open Architecture SCADA (previously known as ETM PVSS) but are being expanded to cover more and more aspects of process control systems. We present what constitutes the UNICOS metamodel and the models in use, how these models can be used to capture knowledge about industrial control systems and how this knowledge can be leveraged to generate both code and configuratio...

  7. New approaches in intelligent control techniques, methodologies and applications

    CERN Document Server

    Kountchev, Roumen

    2016-01-01

    This volume introduces new approaches in intelligent control area from both the viewpoints of theory and application. It consists of eleven contributions by prominent authors from all over the world and an introductory chapter. This volume is strongly connected to another volume entitled "New Approaches in Intelligent Image Analysis" (Eds. Roumen Kountchev and Kazumi Nakamatsu). The chapters of this volume are self-contained and include summary, conclusion and future works. Some of the chapters introduce specific case studies of various intelligent control systems and others focus on intelligent theory based control techniques with applications. A remarkable specificity of this volume is that three chapters are dealing with intelligent control based on paraconsistent logics.

  8. Robust technology and system for management of sucker rod pumping units in oil wells

    Science.gov (United States)

    Aliev, T. A.; Rzayev, A. H.; Guluyev, G. A.; Alizada, T. A.; Rzayeva, N. E.

    2018-01-01

    We propose a technology for calculating the robust, normalized correlation functions of the signal from the force sensor on the rod string attached to the hanger of the sucker rod pumping unit. The robust normalized correlation functions are used to form sets of informative attribute combinations, each of which corresponds to a technical condition of the sucker rod pumping unit. We demonstrate how these sets can be used to solve identification and management problems in the oil production process in real time using inexpensive controllers. The results obtained from using the system on real objects are also presented in this paper. It was determined that the energy saved and prolonged overhaul period substantially increased the cost-effectiveness.

  9. Sb-SnO2 nanoparticles onto kaolinite rods: assembling process and interfacial investigation

    Science.gov (United States)

    Hu, Peiwei; Yang, Huaming

    2012-04-01

    In this article, we reported the synthesis of novel Sb-SnO2/kaolinite (SK) nanocomposites by assembling antimony-doped tin oxide (ATO) nanoparticles on the surface of kaolinite rods without addition of dispersant. The samples were characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution TEM, X-ray photoelectron spectroscopy (XPS), and N2 adsorption-desorption techniques. The crystal size and loading density of ATO nanoparticles onto kaolinite rods could be controlled through the synthetic conditions. The color and resistivity of the composites varied with the loading density of ATO nanoparticles. Investigations of the interfacial binding between ATO layer and rod surface indicated that surface characteristics could facilitate the deposition of various metal oxides nanoparticles. XPS analysis demonstrated that the entrance of Sb5+ into SnO2 crystallite led to the improvement of conductivity and the color change of the composites. The formation mechanism for SK composites was also discussed.

  10. Randomized Algorithms for Systems and Control: Theory and Applications

    Science.gov (United States)

    2008-05-01

    IEIIT-CNR Randomized Algorithms for Systems and Control: Theory and Applications NATO LS Glasgow, Pamplona , Cleveland @RT 2008 Roberto Tempo IEIIT...Glasgow, Pamplona , Cleveland @RT 2008 roberto.tempo@polito.it IEIIT-CNR References R. Tempo, G. Calafiore and F. Dabbene, “Randomized Algorithms for...Analysis and Control of Uncertain Systems,” Springer-Verlag, London, 2005 R Tempo and H Ishii “Monte Carlo and Las Vegas NATO LS Glasgow, Pamplona , Cleveland

  11. Theoretical Development and Application of Discrete Time Quantized Data Controllers

    Science.gov (United States)

    1986-01-01

    Dr. R. P. Judd and P. L. McIntosh School of Engineering & Computer Science Oakland University By Rochester, MI 48063 APPROVED FOR PUBLIC RELEASE...applicable) School of Engr & Cmptr Science 6c. ADDRESS (City, State, and ZIP Code) 7b. ADDRESS (City, State, and ZIP Code) Rochester, MI 48063 8a...controlled external; dcl num state..combs fixed external;’ dcl num..lnput,.combs fixed external; dcl quamtum ~step.size-s (1:n) float controlled external; dcl

  12. Control algorithms and applications of the wavefront sensorless adaptive optics

    Science.gov (United States)

    Ma, Liang; Wang, Bin; Zhou, Yuanshen; Yang, Huizhen

    2017-10-01

    Compared with the conventional adaptive optics (AO) system, the wavefront sensorless (WFSless) AO system need not to measure the wavefront and reconstruct it. It is simpler than the conventional AO in system architecture and can be applied to the complex conditions. Based on the analysis of principle and system model of the WFSless AO system, wavefront correction methods of the WFSless AO system were divided into two categories: model-free-based and model-based control algorithms. The WFSless AO system based on model-free-based control algorithms commonly considers the performance metric as a function of the control parameters and then uses certain control algorithm to improve the performance metric. The model-based control algorithms include modal control algorithms, nonlinear control algorithms and control algorithms based on geometrical optics. Based on the brief description of above typical control algorithms, hybrid methods combining the model-free-based control algorithm with the model-based control algorithm were generalized. Additionally, characteristics of various control algorithms were compared and analyzed. We also discussed the extensive applications of WFSless AO system in free space optical communication (FSO), retinal imaging in the human eye, confocal microscope, coherent beam combination (CBC) techniques and extended objects.

  13. Investigation of the radiation risk due to environmental contamination by 241Am from lightning rods disposed at uncontrolled garbage dumps.

    Science.gov (United States)

    Marumo, Júlio T; Isiki, Vera L K; Miyamoto, Hissae; Ferreira, Rafael V P; Bellini, Maria H; de Lima, Luis F C P

    2008-02-01

    Radioactive lightning rods were manufactured in Brazil until 1989, when the licenses for using radioactive sources in these products were lifted by the national nuclear authority. Since then, these rods have been replaced by the Franklin type and collected as radioactive waste. However, only 20% of the estimated total number of installed rods has been delivered to the Brazilian Nuclear Commission. This situation causes concern, since there is the possibility of the rods to be disposed as domestic waste. In Brazil, 64% of the municipal solid waste is disposed at garbage dumps without sufficient control. In addition, (241)Am, the radionuclide most commonly employed, is classified as a high-toxicity element, when incorporated. In the present study, (241)Am migration experiments were performed by means of a lysimeter system, in order to evaluate the risk of contamination caused by radioactive lightning rods disposed as common solid waste. (241)Am sources removed from lightning rods were placed inside lysimeters filled with organic waste that was collected at the restaurant of the Instituto de Pesquisas Energéticas e Nucleares. The generated leachate was periodically analyzed, and characteristics such as pH, redox potential, solid content and the concentration of the radioactive material were determined. The equivalent dose for members of the public was calculated considering ingestion of contaminated drinking water as the major path of exposure. Estimated doses were about 20-times below the effective dose limit of 1 mSv year(-1) for members of the public as recommended by the International Commission on Radiological Protection. This suggests the radiation risk caused by lightning rods disposed at uncontrolled garbage dumps to be low. It should be noted, however, that the number of investigated lightning rods was quite small. The results of this study might therefore not be entirely representative and should be interpreted with care. They provide, however, a very first

  14. The ATLAS tile calorimeter ROD injector and multiplexer board

    Energy Technology Data Exchange (ETDEWEB)

    Valero, A., E-mail: alberto.valero@cern.c [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC, Paterna, 46071 Valencia (Spain); Castillo, V.; Ferrer, A. [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC, Paterna, 46071 Valencia (Spain); Gonzalez, V. [Departamento de Ingenieria electronica, Universidad de Valencia, Burjassot, 46100 Valencia (Spain); Hernandez, Y.; Higon, E. [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC, Paterna, 46071 Valencia (Spain); Sanchis, E. [Departamento de Ingenieria electronica, Universidad de Valencia, Burjassot, 46100 Valencia (Spain); Solans, C. [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC, Paterna, 46071 Valencia (Spain); Torres, J. [Departamento de Ingenieria electronica, Universidad de Valencia, Burjassot, 46100 Valencia (Spain); Valls, J.A. [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC, Paterna, 46071 Valencia (Spain)

    2011-02-11

    The ATLAS Tile Calorimeter is a sampling detector composed by cells made of iron-scintillator tiles. The calorimeter cell signals are digitized in the front-end electronics and transmitted to the Read-Out Drivers (RODs) at the first level trigger rate. The ROD receives triggered data from up to 9856 channels and provides the energy, phase and quality factor of the signals to the second level trigger. The back-end electronics is divided into four partitions containing eight RODs each. Therefore, a total of 32 RODs are used to process and transmit the data of the TileCal detector. In order to emulate the detector signals in the production and commissioning of ROD modules a board called ROD Injector and Multiplexer Board (RIMBO) was designed. In this paper, the RIMBO main functional blocks, PCB design and the different operation modes are described. It is described the crucial role of the board within the TileCal ROD test-bench in order to emulate the front-end electronics during the validation of ROD boards as well as during the evaluation of the ROD signal reconstruction algorithms. Finally, qualification and performance results for the injection operation mode obtained during the Tile Calorimeter ROD production tests are presented.

  15. Determination of the rod-wise fission gas release fraction in a complete fuel assembly using non-destructive gamma emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Holcombe, Scott, E-mail: scott.holcombe@ife.no [Institute for Energy Technology – OECD Halden Reactor Project, Halden (Norway); Andersson, Peter; Svärd, Staffan Jacobsson [Division of Applied Nuclear Physics, Uppsala University, Uppsala (Sweden); Hallstadius, Lars [Westinghouse Electric Sweden AB, Fredholmsgatan 22, 72163 Västerås (Sweden)

    2016-11-21

    nine rods had cooled for approximately 22 years. All fuel rods had operated at high linear heat rates (around 70 kW/m), thus leading to relatively high FGR fractions. Here, the FGR fraction was determined to be ~24% in the high-burnup rods, and ~17% in the low-burnup rods. The tomography measurement results were in good agreement with the results from individual rod scanning, demonstrating the feasibility of tomography for this application. The capability of tomography to assess individual fuel rods without the need to dismantle the assembly can be particularly valuable in cases of fuels that do not allow disassembly, such as experimental HBWR fuel fitted with extensive instrumentation.

  16. Type-2 Fuzzy Logic in Intelligent Control Applications

    CERN Document Server

    Castillo, Oscar

    2012-01-01

    We describe in this book, hybrid intelligent systems based mainly on type-2 fuzzy logic for intelligent control. Hybrid intelligent systems combine several intelligent computing paradigms, including fuzzy logic, and bio-inspired optimization algorithms, which can be used to produce powerful automatic control systems. The book is organized in three main parts, which contain a group of chapters around a similar subject. The first part consists of chapters with the main theme of theory and design algorithms, which are basically chapters that propose new models and concepts, which can be the basis for achieving intelligent control with interval type-2 fuzzy logic. The second part of the book is comprised of chapters with the main theme of evolutionary optimization of type-2 fuzzy systems in intelligent control with the aim of designing optimal type-2 fuzzy controllers for complex control problems in diverse areas of application, including mobile robotics, aircraft dynamics systems and hardware implementations. Th...

  17. Models for fuel rod behaviour at high burnup

    Energy Technology Data Exchange (ETDEWEB)

    Jernkvist, Lars O.; Massih, Ali R. [Quantum Technologies AB, Uppsala Science Park, Uppsala (Sweden)

    2004-12-01

    This report deals with release of fission product gases and irradiation-induced restructuring in uranium dioxide nuclear fuel. Waterside corrosion of zirconium alloy clad tubes to light water reactor fuel rods is also discussed. Computational models, suitable for implementation in the FRAPCON-3.2 computer code, are proposed for these potentially life-limiting phenomena. Hence, an integrated model for the calculation or thermal fission gas release by intragranular diffusion, gas trapping in grain boundaries, irradiation-induced re-solution, grain boundary saturation, and grain boundary sweeping in UO{sub 2} fuel, under time varying temperature loads, is formulated. After a brief review of the status of thermal fission gas release modelling, we delineate the governing equations for the aforementioned processes. Grain growth kinetic modelling is briefly reviewed and pertinent data on grain growth of high burnup fuel obtained during power ramps in the Third Risoe Fission Gas Release Project are evaluated. Sample computations are performed, which clearly show the connection between fission gas release and gram growth as a function of time at different isotherms. Models are also proposed for the restructuring of uranium dioxide fuel at high burnup, the so-called rim formation, and its effect on fuel porosity build-up, fuel thermal conductivity and fission gas release. These models are assessed by use of recent experimental data from the High Burnup Rim Project, as well as from post irradiation examinations of high-burnup fuel, irradiated in power reactors. Moreover, models for clad oxide growth and hydrogen pickup in PWRs, applicable to Zircaloy-4, ZIRLO or M5 cladding, are formulated, based on recent in-reactor corrosion data for high-burnup fuel rods. Our evaluation of these data indicates that the oxidation rate of ZIRLO-type materials is about 20% lower than for standard Zircaloy-4 cladding under typical PWR conditions. Likewise, the oxidation rate of M5 seems to be

  18. Internal Administrative Control: Its Applicability to the Marine Corps.

    Science.gov (United States)

    1984-06-01

    SISTEM EVALUATION ..... 93 F. SUMMARY ..... . . . . . . . . . . . .. 96 V. AN OZERATIONAI rEZINITICN OF ADMINISTRATIVE CCN7FOL 98 1I. ANAIISIS...levied reslonsitility on the independenit auditor tc review *the accumulated evidence in accordance with generally accepted auditing standards and to...within the auditing profession over the definition. of internal control and its applicability to the indepeadent auditor . The AICPA formally adopted

  19. Modelling primate control of grasping for robotics applications

    CSIR Research Space (South Africa)

    Kleinhans, A

    2014-09-01

    Full Text Available -1 European Conference on Computer Vision (ECCV) Workshops, Zurich, Switzerland, 7 September 2014 Modelling primate control of grasping for robotics applications Ashley Kleinhans1, Serge Thill2, Benjamin Rosman1, Renaud Detry3 & Bryan Tripp4 1 CSIR...

  20. Application of fuzzy logic in the control of polymerization reactors

    NARCIS (Netherlands)

    Roffel, B.; Chin, P.A.

    1993-01-01

    Polymer reactors are ideal candidates for the application of fuzzy control. Many polymerization reactions are difficult to model, process measurements are often only available from laboratory analysis at infrequent time intervals and trace impurities can have a marked effect on the reaction. All

  1. DARC: Next generation decentralized control framework for robot applications

    DEFF Research Database (Denmark)

    Kjærgaard, Morten; Andersen, Nils Axel; Ravn, Ole

    2013-01-01

    This paper presents DARC, a next generation control framework for robot applications. It is designed to be equally powerful in prototyping research projects and for building serious commercial robots running on low powered embedded hardware, thus closing the gab between research and industry...

  2. Robust Control for High-Speed Visual Servoing Applications

    DEFF Research Database (Denmark)

    Ellekilde, Lars-Peter; Favrholdt, Peter; Paulin, Mads

    2007-01-01

    This paper presents a new control scheme for visual servoing applications. The approach employs quadratic optimization, and explicitly handles both joint position, velocity and acceleration limits. Contrary to existing techniques, our method does not rely on large safety margins and slow task exe...

  3. Biopolymers in controlled release devices for agricultural applications.

    Science.gov (United States)

    The use of biopolymers such as starch for agricultural applications including controlled release devices is growing due the environmental benefits. Recently, concerns have grown about the worldwide spread of parasitic mites (Varroa destructor) that infect colonies of honey bees (Apis mellifera L.). ...

  4. Closed-Loop Optimal Control Implementations for Space Applications

    Science.gov (United States)

    2016-12-01

    COVERED Master’s thesis , Jan-Dec 2016 4. TITLE AND SUBTITLE CLOSED-LOOP OPTIMAL CONTROL IMPLEMENTATIONS FOR SPACE APPLICATIONS 5. FUNDING NUMBERS... Mechanical and Aerospace Engineering iv THIS PAGE INTENTIONALLY LEFT BLANK v ABSTRACT This thesis explores concepts for a closed-loop optimal...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release. Distribution is unlimited. CLOSED-LOOP

  5. Application of infinite model predictive control methodology to other advanced controllers.

    Science.gov (United States)

    Abu-Ayyad, M; Dubay, R; Hernandez, J M

    2009-01-01

    This paper presents an application of most recent developed predictive control algorithm an infinite model predictive control (IMPC) to other advanced control schemes. The IMPC strategy was derived for systems with different degrees of nonlinearity on the process gain and time constant. Also, it was shown that IMPC structure uses nonlinear open-loop modeling which is conducted while closed-loop control is executed every sampling instant. The main objective of this work is to demonstrate that the methodology of IMPC can be applied to other advanced control strategies making the methodology generic. The IMPC strategy was implemented on several advanced controllers such as PI controller using Smith-Predictor, Dahlin controller, simplified predictive control (SPC), dynamic matrix control (DMC), and shifted dynamic matrix (m-DMC). Experimental work using these approaches combined with IMPC was conducted on both single-input-single-output (SISO) and multi-input-multi-output (MIMO) systems and compared with the original forms of these advanced controllers. Computer simulations were performed on nonlinear plants demonstrating that the IMPC strategy can be readily implemented on other advanced control schemes providing improved control performance. Practical work included real-time control applications on a DC motor, plastic injection molding machine and a MIMO three zone thermal system.

  6. Chaos in electric drive systems analysis control and application

    CERN Document Server

    Chau, K T

    2011-01-01

    In Chaos in Electric Drive Systems: Analysis, Control and Application authors Chau and Wang systematically introduce an emerging technology of electrical engineering that bridges abstract chaos theory and practical electric drives. The authors consolidate all important information in this interdisciplinary technology, including the fundamental concepts, mathematical modeling, theoretical analysis, computer simulation, and hardware implementation. The book provides comprehensive coverage of chaos in electric drive systems with three main parts: analysis, control and application. Corresponding drive systems range from the simplest to the latest types: DC, induction, synchronous reluctance, switched reluctance, and permanent magnet brushless drives.The first book to comprehensively treat chaos in electric drive systemsReviews chaos in various electrical engineering technologies and drive systemsPresents innovative approaches to stabilize and stimulate chaos in typical drivesDiscusses practical application of cha...

  7. Access Control of Web and Java Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.; Johnson, Bryan

    2011-01-01

    Cyber security has gained national and international attention as a result of near continuous headlines from financial institutions, retail stores, government offices and universities reporting compromised systems and stolen data. Concerns continue to rise as threats of service interruption, and spreading of viruses become ever more prevalent and serious. Controlling access to application layer resources is a critical component in a layered security solution that includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. In this paper we discuss the development of an application-level access control solution, based on an open-source access manager augmented with custom software components, to provide protection to both Web-based and Java-based client and server applications.

  8. Mathematical Modeling of the Thermal State of the Spatial Layered Rod Structures

    Directory of Open Access Journals (Sweden)

    I. V. Stankevich

    2016-01-01

    Full Text Available The paper considers the features of finite element technology to determine the temperature state of layered rod structures with complex spatial design. The area of research, on the one hand, is defined by the fact that the rod structures (frames are so-called “skeletal framework” of aviation, machinery, shipbuilding products and structures for industrial construction and an issue of implementation of most research and industrial projects, strongly promising from the practical point of view, depends largely on the level of reliability, bearing capacity, and general performance of its “skeletal framework”. On the other hand, the laminates have a wide range and unique combination of valuable properties such as high strength, corrosion resistance, electrical conductivity, thermal conductivity, heat resistance, abrasion resistance and many others. The use of layered metal compositions allows to increase the reliability and durability of a large range of parts and equipment and to reduce significantly the consumption of high-alloyed steels and nonferrous metals. A temperature field is one of the main factors to determine the expected performance of multilayer rod structures, operation conditions of which imply intensive thermal loading.The paper shows how within a single finite element model that approximates the spatial design of steel structures consisting of multilayer curvilinear rods, at the stage of discretization in space to take into account the thermo-physical properties of all materials, forming layer of each timber. Using the technique described in the paper has been created a complex of application programs that allows us to solve a wide class of scientific and applied problems, and explore the impact of various structural, technological and operational factors on the temperature state of multilayer rod structures. The paper presents research results of the multilayer rod design. It shows that the high conductivity layer available

  9. Calculation model of non-linear dynamic deformation of composite multiphase rods

    Directory of Open Access Journals (Sweden)

    Mishchenko Andrey Viktorovich

    2014-05-01

    Full Text Available The method of formulating non-linear physical equations for multiphase rods is suggested in the article. Composite multiphase rods possess various structures, include shear, polar, radial and axial inhomogeneity. The Timoshenko’s hypothesis with the large rotation angles is used. The method is based on the approximation of longitudinal normal stress low by basic functions expansions regarding the linear viscosity low. The shear stresses are calculated with the equilibrium equation using the subsidiary function of the longitudinal shift force. The system of differential equations connecting the internal forces and temperature with abstract deformations are offered by the basic functions. The application of power functions with arbitrary index allows presenting the compact form equations. The functional coefficients in this system are the highest order rigidity characteristics. The whole multiphase cross-section rigidity characteristics are offered the sums of the rigidity characteristics of the same phases individually. The obtained system allows formulating the well-known particular cases. Among them: hard plasticity and linear elastic deformation, different module deformation and quadratic Gerstner’s low elastic deformation. The reform of differential equations system to the quasilinear is suggested. This system contains the secant variable rigidity characteristics depending on abstract deformations. This system includes the sum of the same uniform blocks of different order. The rods phases defined the various set of uniform blocks phase materials. The integration of dynamic, kinematic and physical equations taking into account initial and edge condition defines the full dynamical multiphase rods problem. The quasilinear physical equations allow getting the variable flexibility matrix of multiphase rod and rods system.

  10. Rod strain after pedicle subtraction osteotomy

    DEFF Research Database (Denmark)

    Gehrchen, Poul Martin; Hallager, Dennis Winge; Dahl, Benny

    2016-01-01

    Pedicle subtraction osteotomy (PSO) can provide major sagittal correction for adult spinal deformity, sometimes achieving correction greater than 308. Surgeons have reported failure rates up to 30% within 2 years, increasing to 46% after 4 to 5 years (SDC Figure 1, http://links.lww.com/BRS/B87......). Revision following failure is difficult on the patient. PSO has achieved positive outcomes, but when used to correct posture in older patients with spinal deformity and fixed sagittal imbalance, rod breakage often leads to multiple surgical revisions. These complications must be avoided....

  11. Rodded shutdown system for a nuclear reactor

    Science.gov (United States)

    Golden, Martin P.; Govi, Aldo R.

    1978-01-01

    A top mounted nuclear reactor diverse rodded shutdown system utilizing gas fed into a pressure bearing bellows region sealed at the upper extremity to an armature. The armature is attached to a neutron absorber assembly by a series of shafts and connecting means. The armature is held in an uppermost position by an electromagnet assembly or by pressurized gas in a second embodiment. Deenergizing the electromagnet assembly, or venting the pressurized gas, causes the armature to fall by the force of gravity, thereby lowering the attached absorber assembly into the reactor core.

  12. 4-rod RFQ linac for ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Fujisawa, Hiroshi; Hamamoto, Nariaki; Inouchi, Yutaka [Nisshin Electric Co. Ltd., Kyoto (Japan)

    1997-03-01

    A 34 MHz 4-rod RFQ linac system has been upgraded in both its rf power efficiency and beam intensity. The linac is able to accelerate in cw operation 0.83 mA of a B{sup +} ion beam from 0.03 to 0.91 MeV with transmission of 61 %. The rf power fed to the RFQ is 29 kW. The unloaded Q-value of the RFQ has been improved approximately 61 % to 5400 by copper-plating stainless steel cooling pipes in the RFQ cavity. (author)

  13. Nonlinear localized elastoplastic waves in a rod

    Science.gov (United States)

    Erofeev, V. I.; Leonteva, A. V.; Malkhanov, A. O.

    2017-11-01

    It has been shown that longitudinal nonlinear stationary elastic-plastic waves can be formed in a rod. Waves can be both periodic and solitary (solitons), which is determined by the index of strain hardening of the material.The velocity of propagation of such waves is less than the speed of the elastic shear wave. Along with classical solitons, so-called “embedded solitons” can be formed, that is, double solitons, one of which with a smaller amplitude and widthis located inside the other with a larger amplitude and width.

  14. Uspon silovatelja: etnicitet, rod i nasilje

    OpenAIRE

    Mežnarić, Silva

    1993-01-01

    Članak raspravlja o uporabi silovanja kao politike u slučajevima kada se, do tragičnih posljedica, ukrštaju nasilje, rod i etnicitet. Prvo se ispituje kampanja srbijanskih medija 1990. na Kosovu protiv Albanaca kao silovatelja; zatim se analizira upotreba silovanja u prinudnom etničkom čišćenju prilikom srpske agresije na Bosnu, 1992-1993. Pokazuje se da je kampanja na Kosovu bila predigra stvarnom silovanju u Bosni. U oba je slučaja silovanje poslužilo u ograđivanju teritorija i definiranju ...

  15. Solitary waves on nonlinear elastic rods. I

    DEFF Research Database (Denmark)

    Sørensen, Mads Peter; Christiansen, Peter Leth; Lomdahl, P. S.

    1984-01-01

    Acoustic waves on elastic rods with circular cross section are governed by improved Boussinesq equations when transverse motion and nonlinearity in the elastic medium are taken into account. Solitary wave solutions to these equations have been found. The present paper treats the interaction between...... the solitary waves numerically. It is demonstrated that the waves behave almost like solitons in agreement with the fact that the improved Boussinesq equations are nearly integrable. Thus three conservation theorems can be derived from the equations. A new subsonic quasibreather is found in the case of a cubic...

  16. ADAPTIVE OUTPUT CONTROL: SUBJECT MATTER, APPLICATION TASKS AND SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Alexey A. Bobtsov

    2013-01-01

    Full Text Available The problem of adaptive output control for parametric and functionally uncertain plants is considered. Application examples illustrating the practical use of the discussed theory are given along with the mathematical formulation of the problem. A brief review of adaptive output control methods, by both linear and non-linear systems, is presented and an extensive bibliography, in which the reader will find a detailed description of the specific algorithms and their properties, is represented. A new approach to the output control problem - a method of consecutive compensator - is considered in detail.

  17. Optimal control theory applications to management science and economics

    CERN Document Server

    Sethi, Suresh P

    2006-01-01

    Optimal control methods are used to determine the best ways to control a dynamic system. This book applies theoretical work to business management problems developed from the authors' research and classroom instruction. The thoroughly revised new edition has been refined with careful attention to the text and graphic material presentation. Chapters cover a range of topics including finance, production and inventory problems, marketing problems, machine maintenance and replacement, problems of optimal consumption of natural resources, and applications of control theory to economics. The book in

  18. Engineering applications of discrete-time optimal control

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui; Ravn, Hans V.

    1990-01-01

    Many problems of design and operation of engineering systems can be formulated as optimal control problems where time has been discretisized. This is also true even if 'time' is not involved in the formulation of the problem, but rather another one-dimensional parameter. This paper gives a review...... of some well-known and new results in discrete time optimal control methods applicable to practical problem solving within engineering. Emphasis is placed on dynamic programming, the classical maximum principle and generalized versions of the maximum principle for optimal control of discrete time systems...

  19. PRODUCTIVITY OF TOMATO PLANTS PULVERIZED WITH CALCIUM AND BORON ON THE NUMBER OF RODS

    Directory of Open Access Journals (Sweden)

    A. R. Zeist

    2016-07-01

    Full Text Available Context in which mineral nutrients Ca and B and the form that plants are conducted has great influence on productive aspects of the tomato crop. The objective of this research was to evaluate the effect of tomato foliar sprays of Ca and B, and the number of stems. To run the experiment genotype tomato hybrid Absolute®, belonging to the group salad, the plot was sprayed with all combinations (C possible for (calcium (Ca + boron (B, and the subplot about the number of rods: (H1 - (one rod and H2 - (two rods. Throughout the cycle were evaluated: number of marketable fruits (CF and non-commercial (FNC and marketable fruit yield (PFC and non-commercial (PFNC. According to the results, it was found that there was only interaction to the number of non-marketable fruit variable. By means of spraying, it was found that the isolated foliar application of B, can increase the number of commercial fruit, and the combined foliar application of (Ca + B, allows to decrease the production of non-commercial fruits. And as to the number of rods, that driving with two tomato stem is more appropriate.

  20. Impedance Coordinative Control for Cascaded Converter in Bidirectional Application

    DEFF Research Database (Denmark)

    Tian, Yanjun; Deng, Fujin; Chen, Zhe

    2015-01-01

    Two stage cascaded converters are widely used in bidirectional applications, but the negative impedance may cause system instability. Actually the impedance interaction is much different between forward power flow and reversed power flow, which will introduce more uncertainty to the system...... stability. This paper proposes a control method for the constant power controlled converter in cascaded system, and consequently it can change the negative impedance of constant power converter into resistive impedance, which will improve the cascaded system stability, as well as merge the impedance...... difference between forward and reversed power flow. This paper addresses the analysis with the topology of cascaded dual-active-bridge converter (DAB) with inverter, and the proposed control method can also be implemented in unidirectional applications and other general cascaded converter system...

  1. APPLICATION OF MULTIVARIATE CONTROL CHARTS FOR MONITORING AN INDUSTRIAL PROCESS

    Directory of Open Access Journals (Sweden)

    Custodio da Cunha Alves

    2013-12-01

    Full Text Available The effective simultaneous monitoring of the many quality characteristics of a production process often depends on statistical tools that are becoming more and more specific. The goal of this paper is to investigate, via an industrial application, if there are significant differences in sensitivity between the use of Multivariate Cumulative Sum (MCUSUM, Multivariate Exponentially Weighted Average (MEWMA control charts and Hotelling T2 charts in the detection of small changes in the vector of means of the process. In doing this study, we used real data from a machining process. A MCUSUM control chart was applied to monitor the two quality characteristics of this process simultaneously. A MEWMA chart was also applied. The result was compared to the application of the Hotelling T2 chart, which showed that the MCUSUM and MEWMA control charts detected the change sooner. This study was fundamental in defining the best choice between the three charts for the multivariate statistical analysis of this industrial process.

  2. Control of Linear Parameter Varying Systems with Applications

    CERN Document Server

    Mohammadpour, Javad

    2012-01-01

    Control of Linear Parameter Varying Systems with Applications compiles state-of-the-art contributions on novel analytical and computational methods to address system modeling and identification, complexity reduction, performance analysis and control design for time-varying and nonlinear systems in the LPV framework. The book has an interdisciplinary character by emphasizing techniques that can be commonly applied in various engineering fields. It also includes a rich collection of illustrative applications in diverse domains to substantiate the effectiveness of the design methodologies and provide pointers to open research directions. The book is divided into three parts. The first part collects chapters of a more tutorial character on the background of LPV systems modeling and control. The second part gathers chapters devoted to the theoretical advancement of LPV analysis and synthesis methods to cope with the design constraints such as uncertainties and time delay. The third part of the volume showcases con...

  3. GASICA: Generic Automated Stress Induction and Control ApplicationDesign of an application for controlling the stress state

    Directory of Open Access Journals (Sweden)

    Benny Van Der Vijgh

    2014-12-01

    Full Text Available 1.In a multitude of research and therapy paradigms it is relevant to know, and desirably to control, the stress state of a patient or participant. Examples include research paradigms in which the stress state is the dependent or independent variable, or therapy paradigms where this state indicates the boundaries of the therapy. To our knowledge, no application currently exists that focuses specifically on the automated control of the stress state while at the same time being generic enough to be used in various therapy and research purposes. Therefore, we introduce GASICA, an application aimed at the automated control of the stress state in a multitude of therapy and research paradigms. The application consists of three components: a digital stressor game, a set of measurement devices and a feedback model. These three components form a closed loop (called a biocybernetic loop by Pope, Bogart, & Bartolome, 1995 and Fairclough, 2009 that continuously presents an acute psychological stressor, measures several physiological responses to this stressor, and adjusts the stressor intensity based on these measurements by means of the feedback model, hereby aiming to control the stress state. In this manner GASICA presents multidimensional and ecological valid stressors, whilst continuously in control of the form and intensity of the presented stressors, aiming at the automated control of the stress state. Furthermore, the application is designed as a modular open-source application to easily implement different therapy and research tasks using a high-level programming interface and configuration file, and allows for the addition of (existing measurement equipment, making it usable for various paradigms.

  4. Improvement to the pattern of control rods of the equilibrium cycle of 18 months for the CLV using bio-inspired algorithms; Mejora del patron de barras de control del ciclo de equilibrio de 18 meses para la CLV empleando algoritmos bio-inspirados

    Energy Technology Data Exchange (ETDEWEB)

    Perusquia, R.; Ortiz, J.J.; Montes, J.L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: rpc@nuclear.inin.mx

    2003-07-01

    Nowadays in the National Institute of Nuclear Research are carried out studies with some bio-inspired optimization techniques to improve the performance of the fuel cycles of the boiling water reactors of the Laguna Verde power plant (CLV). In the present work two bio-inspired techniques were applied with the purpose of improving the performance of a balance cycle of 18 months developed for the CLV: genetic algorithms (AG) and systems based on ants colonies (SCH). The design of the reference cycle it represents in several aspects an optimal cycle proposed starting from the experience of several operation decades with the boiling water reactors (BWR initials for Boiling Water Reactor) in the world. To try to improve their performance is beforehand a difficult challenge and it puts on test the feasibility of the optimization methods in the reloads design. The study of the bio-inspired techniques was centered exclusively on the obtaining of the control rod patterns (PBC) trying to overcome the capacity factor reached in the design of the reference cycle. It was fixed the cycle length such that the decrease of the coast down period would represent an increase of the capacity factor of the cycle; so that, it diminishes the annual cost associated with the capital cost of the plant. As consequence of the study, was found that the algorithm based on the ants colonies reaches to diminish the coast down period in five and half days respect to the original balance cycle, what represents an annual saving of $US 74,000. Since the original cycle was optimized, the above-mentioned, shows the ability of the SCH for the optimization of the cycle design. With the AG it was reach to approach to the original balance cycle with a coast down period greater in seven days estimating an annual penalization of $US 130,000. (Author)

  5. A Graph Based Approach to Nonlinear Model Predictive Control with Application to Combustion Control and Flow Control

    Science.gov (United States)

    2015-08-21

    nitrous oxides (NOx) are not considered because their formation process is not well understood [32]. 30 Figure 4.1: Single Output Neural Network ID...local minimum. Multiple-Input Multiple-Output (MIMO) results are obtained for the combustion control simulation. The second practical application...tasks are recorded so that the results obtained here may be reproduced. This dissertation develops a control system for general application to systems

  6. Disturbance Accommodating Adaptive Control with Application to Wind Turbines

    Science.gov (United States)

    Frost, Susan

    2012-01-01

    Adaptive control techniques are well suited to applications that have unknown modeling parameters and poorly known operating conditions. Many physical systems experience external disturbances that are persistent or continually recurring. Flexible structures and systems with compliance between components often form a class of systems that fail to meet standard requirements for adaptive control. For these classes of systems, a residual mode filter can restore the ability of the adaptive controller to perform in a stable manner. New theory will be presented that enables adaptive control with accommodation of persistent disturbances using residual mode filters. After a short introduction to some of the control challenges of large utility-scale wind turbines, this theory will be applied to a high-fidelity simulation of a wind turbine.

  7. ER fluid applications to vibration control devices and an adaptive neural-net controller

    Science.gov (United States)

    Morishita, Shin; Ura, Tamaki

    1993-07-01

    Four applications of electrorheological (ER) fluid to vibration control actuators and an adaptive neural-net control system suitable for the controller of ER actuators are described: a shock absorber system for automobiles, a squeeze film damper bearing for rotational machines, a dynamic damper for multidegree-of-freedom structures, and a vibration isolator. An adaptive neural-net control system composed of a forward model network for structural identification and a controller network is introduced for the control system of these ER actuators. As an example study of intelligent vibration control systems, an experiment was performed in which the ER dynamic damper was attached to a beam structure and controlled by the present neural-net controller so that the vibration in several modes of the beam was reduced with a single dynamic damper.

  8. COMPUTER MODEL OF TEMPERATURE DISTRIBUTION IN OPTICALLY PUMPED LASER RODS

    Science.gov (United States)

    Farrukh, U. O.

    1994-01-01

    Managing the thermal energy that accumulates within a solid-state laser material under active pumping is of critical importance in the design of laser systems. Earlier models that calculated the temperature distribution in laser rods were single dimensional and assumed laser rods of infinite length. This program presents a new model which solves the temperature distribution problem for finite dimensional laser rods and calculates both the radial and axial components of temperature distribution in these rods. The modeled rod is either side-pumped or end-pumped by a continuous or a single pulse pump beam. (At the present time, the model cannot handle a multiple pulsed pump source.) The optical axis is assumed to be along the axis of the rod. The program also assumes that it is possible to cool different surfaces of the rod at different rates. The user defines the laser rod material characteristics, determines the types of cooling and pumping to be modeled, and selects the time frame desired via the input file. The program contains several self checking schemes to prevent overwriting memory blocks and to provide simple tracing of information in case of trouble. Output for the program consists of 1) an echo of the input file, 2) diffusion properties, radius and length, and time for each data block, 3) the radial increments from the center of the laser rod to the outer edge of the laser rod, and 4) the axial increments from the front of the laser rod to the other end of the rod. This program was written in Microsoft FORTRAN77 and implemented on a Tandon AT with a 287 math coprocessor. The program can also run on a VAX 750 mini-computer. It has a memory requirement of about 147 KB and was developed in 1989.

  9. Grey Rod Test in HANARO Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Choo, K. N.; Kim, B. G.; Kang, Y. H. (and others)

    2008-08-15

    Westinghouse/KAERI/KNF agreed to perform an irradiation test in the HANARO reactor to obtain irradiation data on the new grey rods that will be part of an AP1000 system. As a preliminary test, two samples containing pure Ag (Reference) and Ag-In-Cd materials provided by Westinghouse Electric Company (WEC) were inserted in a KNF irradiation capsule of 07M-13N. The specimens were irradiated for 95.19days (4 cycles) in the CT test hole of the HANARO of a 30MW thermal output to have a fast neutron fluence of 1.11x10{sup 21}(n/cm{sup 2}) (E>1.0MeV). This report provides all the test conditions and data obtained during the irradiation test of the grey rods in HANARO requested by Westinghouse. The test was prepared according to the meeting minutes (June 26, 2007) and the on-going subject test was stopped midway by the request of Westinghouse.

  10. Push rod for moving mine cars

    Energy Technology Data Exchange (ETDEWEB)

    Shtokman, I.G.; Apukhtin, A.S.; Dudnik, M.Z.; Remizov, I.P.; Shakhtar, P.S.

    1981-01-01

    In the operation of the known pushrods for haulage of cars on horizontal shafts, it becomes necessary to slow down the moving cars. In normal working modes, braking of the cars is guaranteed by counter engagement of the linear motors. However when emergency situations develop, for example if there is some lack of voltage in the network, it becomes necessary to brake the cars which this device cannot guarantee. The purpose of the invention is to brake the cars with disconnection of power. The goal is achieved because the push rod containing a frame with inductors attached to it installed on the sides of the rail path opposite each other, in which the cabs of the cars fill the role of the rotor, the support stands are connected to the inductors by means of springs, and the frame with inductors is hinged to the support stand and has mechanism for regulating the gap between the inductors and the cars, made in the form of rollers attached to the frame for interaction with the outer sidewalls of the car is equipped with friction elements installed on the frame and electromagnets with spring-rods installed on the support stands arranged with the possibility of interacting with the frame, and each friction element is arranged with the possibility of interacting with the rollers.

  11. Model-Driven Development of Automation and Control Applications: Modeling and Simulation of Control Sequences

    Directory of Open Access Journals (Sweden)

    Timo Vepsäläinen

    2014-01-01

    Full Text Available The scope and responsibilities of control applications are increasing due to, for example, the emergence of industrial internet. To meet the challenge, model-driven development techniques have been in active research in the application domain. Simulations that have been traditionally used in the domain, however, have not yet been sufficiently integrated to model-driven control application development. In this paper, a model-driven development process that includes support for design-time simulations is complemented with support for simulating sequential control functions. The approach is implemented with open source tools and demonstrated by creating and simulating a control system model in closed-loop with a large and complex model of a paper industry process.

  12. Packaged peristaltic micropump for controlled drug delivery application

    Science.gov (United States)

    Vinayakumar, K. B.; Nadiger, Girish; R. Shetty, Vikas; Dinesh, N. S.; Nayak, M. M.; Rajanna, K.

    2017-01-01

    Micropump technology has evolved significantly in the last two decades and is finding a variety of applications ranging from μTAS (micro Total Analysis System) to drug delivery. However, the application area of the micropump is limited owing to: simple pumping mechanism, ease of handling, controlled (microliter to milliliter) delivery, continuous delivery, and accuracy in flow rate. Here, the author presents the design, development, characterization, and precision flow controlling of a DC-motor driven peristaltic pump for controlled drug delivery application. All the micropump components were fabricated using the conventional fabrication technique. The volume flow variation of the pump has been characterized for different viscous fluids. The change in volume flow due to change in back pressure has been presented in detail. The fail-safe mode operation of the pump has been tested and leak rate was measured (˜0.14% leak for an inlet pressure of 140 kPa) for different inlet pressures. The precision volume flow of the pump has been achieved by measuring the pinch cam position and load current. The accuracy in the volume flow has been measured after 300 rotations. Finally, the complete system has been integrated with the necessary electronics and an android application has been developed for the self-administration of bolus and basal delivery of insulin.

  13. On the Wave Stresses in the Rods of Anvil Hammers

    Directory of Open Access Journals (Sweden)

    V. M. Sinitskiy

    2014-01-01

    Full Text Available With operating anvil hammers, there are rigid impacts of die tools, and as a result, almost instantaneous impact stops of the falling parts of hammer. Such operating conditions lead to the accelerated breakdowns of rods because of significant wave stresses arising in them. Common differential and integral methods to estimate wave stresses are widespread in engineering practice. However, to use them a researcher has to possess certain skills and special software. We consider the method for estimating the wave stresses in the rods of anvil hammers based on Laplace transforms (LT of wave equation. The article shows a procedure to set up and solve differential wave equations by operator method. These equations describe the wave propagation process of strains and stresses in the rods of anvil hammers with rigid impact and taking into account a damping rod connection with the head of hammer. The method takes into consideration an influence of both piston and rod weights and of mechanical and geometrical characteristics of rod on the stress value in the placement of rod in hammer head. Results analysis shows that a sufficiently efficient method for practical improving the durability of rods is the method of damping impact load on the rod through setting the damping devices in the form either of elastic "pad" of one or another design or of hydraulic shock absorbers in the placement of its connection with the hammer head. In this case there is a change of the wave front, it becomes flatter. It is shown that the stresses in the rod are proportional to the amount of wave stresses because of the own impact of rod and piston, which make a total weight of the system. Effect of piston weight on the stresses value at the rod during impact is directly proportional to the ratio of its weight to the rod weight. The geometric parameters of rod and the speed of the falling parts before the impact also influence on the value of stresses in the rod.The represented

  14. Vortex patterns in a superconducting-ferromagnetic rod

    Energy Technology Data Exchange (ETDEWEB)

    Romaguera, Antonio R. de C, E-mail: antonio.romaguera@df.ufrpe.b [Departamento de Fi' sica, Universidade Federal Rural de Pernambuco, 52171-900 Recife, Pernambuco (Brazil); Doria, Mauro M. [Departamento de Fi' sica dos Solidos, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro (Brazil); Peeters, Francois M. [Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen (Belgium)

    2010-10-01

    A superconducting rod with a magnetic moment on top develops vortices obtained here through 3D calculations of the Ginzburg-Landau theory. The inhomogeneity of the applied field brings new properties to the vortex patterns that vary according to the rod thickness. We find that for thin rods (disks) the vortex patterns are similar to those obtained in presence of a homogeneous magnetic field instead because they consist of giant vortex states. For thick rods novel patterns are obtained as vortices are curve lines in space that exit through the lateral surface.

  15. TileCal ROD Hardware and Software Requirements

    CERN Document Server

    Castelo, J; Cuenca, C; Ferrer, A; Fullana, E; Higón, E; Iglesias, C; Munar, A; Poveda, J; Ruiz-Martínez, A; Salvachúa, B; Solans, C; Valls, J A

    2005-01-01

    In this paper we present the specific hardware and firmware requirements and modifications to operate the Liquid Argon Calorimeter (LiArg) ROD motherboard in the Hadronic Tile Calorimeter (TileCal) environment. Although the use of the board is similar for both calorimeters there are still some differences in the operation of the front-end associated to both detectors which make the use of the same board incompatible. We review the evolution of the design of the ROD from the early prototype stages (ROD based on commercial and Demonstrator boards) to the production phases (ROD final board based on the LiArg design), with emphasis on the different operation modes for the TileCal detector. We start with a short review of the TileCal ROD system functionality and then we detail the different ROD hardware requirements for options, the baseline (ROD Demo board) and the final (ROD final high density board). We also summarize the performance parameters of the ROD motherboard based on the final high density option and s...

  16. Fuel rod under power oscillations; calculations with the ENIGMA code

    Energy Technology Data Exchange (ETDEWEB)

    Ranta-Puska, Kari

    1999-05-15

    Power oscillations in a BWR may result from a series of events starting from a re-circulation pump trip or can be initiated during start-up at low-flow conditions by other perturbations. Whole core and regional oscillations have been observed. Severe consequences may be anticipated if the instability diverges and the reactor protection system fails (no scram) in all phases of the incident (ATWS). Power peaks higher than ten times of the pre-transient power level have been speculated to appear. Low-magnitude oscillations have been observed at the TVO plant, Olkiluoto 1987, and at the Lasalle-2 plant, 1988, and in other BWRs world-wide. Typically, a boiling water reactor has an unstable operational point at low flow and high power conditions. The physical phenomenon behind the instability is density wave oscillations leading to boiling boundary oscillations and void fraction fluctuations across the heated channel. These in turn, make the fission power vary. The typical frequency of the oscillations seems to be of the order of 0.5 Hz, and thus the power peak for a fuel rod is considerably wider than a RIA-pulse, for instance. Large oscillations can result in elevated fuel temperatures, accelerated fission gas release and additional internal loads on the cladding. These effects may be more severe for a high burnup rod with a large fission gas inventory and a closed gap. Therefore, an experiment has been proposed to be conducted at Halden reactor for simulating the fuel rod response under power oscillations. As there is lack of knowledge also on the relevant boundary conditions, pre-calculations with various input options have been performed and are further suggested. Calculations with FRAPTRAN code have shown the importance of the cladding-coolant heat transfer to the fuel temperature. The applicability of the ENIGMA code to this kind of transients was confirmed. To support the planning of the proposed Halden test, estimates on fuel and cladding temperatures as well as

  17. Local plate/rod descriptors of 3D trabecular bone micro-CT images from medial axis topologic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Peyrin, Francoise; Attali, Dominique; Chappard, Christine; Benhamou, Claude Laurent [CREATIS, UMR CNRS 5220, 69621 Villeurbanne (France); Inserm, U 630, 69621 Villeurbanne (France); Insa de Lyon, 69621 Villeurbanne (France); Universite Lyon I, 69621 Villeurbanne (France); Universite de Lyon, 69621 Villeurbanne (France) and ESRF (European Synchrotron Radiation Facility), BP 220, 38043 Grenoble (France); GIPSA Laboratory, UMR CNRS 5216, 38402 Grenoble (France); Inserm, U 658, 45032 Orleans Cedex 1 (France) and B20A, UMR7052 CNRS, Universite Paris 7, 75010 Paris (France); Inserm, U 658, 45032 Orleans Cedex 1 (France)

    2010-08-15

    Purpose: Trabecular bone microarchitecture is made of a complex network of plate and rod structures evolving with age and disease. The purpose of this article is to propose a new 3D local analysis method for the quantitative assessment of parameters related to the geometry of trabecular bone microarchitecture. Methods: The method is based on the topologic classification of the medial axis of the 3D image into branches, rods, and plates. Thanks to the reversibility of the medial axis, the classification is next extended to the whole 3D image. Finally, the percentages of rods and plates as well as their mean thicknesses are calculated. The method was applied both to simulated test images and 3D micro-CT images of human trabecular bone. Results: The classification of simulated phantoms made of plates and rods shows that the maximum error in the quantitative percentages of plate and rods is less than 6% and smaller than with the structure model index (SMI). Micro-CT images of human femoral bone taken in osteoporosis and early or advanced osteoarthritis were analyzed. Despite the large physiological variability, the present method avoids the underestimation of rods observed with other local methods. The relative percentages of rods and plates were not significantly different between osteoarthritis and osteoporotic groups, whereas their absolute percentages were in relation to an increase of rod and plate thicknesses in advanced osteoarthritis with also higher relative and absolute number of nodes. Conclusions: The proposed method is model-independent, robust to surface irregularities, and enables geometrical characterization of not only skeletal structures but entire 3D images. Its application provided more accurate results than the standard SMI on simple simulated phantoms, but the discrepancy observed on the advanced osteoarthritis group raises questions that will require further investigations. The systematic use of such a local method in the characterization of

  18. Helicopter individual-blade-control and its applications

    Science.gov (United States)

    Ham, N. D.

    1984-01-01

    A new, advanced type of active control for helicopters and its applications are described. The system, based on previously developed M.I.T. Individual-Blade-Control hardware, employs blade-mounted accelerometers to sense blade motion and feeds back information to control blade pitch in such a manner as to reduce the response of selected blade modes. A linear model of the blade and control system dynamics is used to give guidance in the design process as well as to aid in analysis of experimental results. System performance in wind tunnel tests is described, and evidence is given of the system's ability to provide substantial reduction in blade modal responses, including blade bending vibration.

  19. Neural networks for process control and optimization: two industrial applications.

    Science.gov (United States)

    Bloch, Gérard; Denoeux, Thierry

    2003-01-01

    The two most widely used neural models, multilayer perceptron (MLP) and radial basis function network (RBFN), are presented in the framework of system identification and control. The main steps for building such nonlinear black box models are regressor choice, selection of internal architecture, and parameter estimation. The advantages of neural network models are summarized: universal approximation capabilities, flexibility, and parsimony. Two applications are described in steel industry and water treatment, respectively, the control of alloying process in a hot dipped galvanizing line and the control of a coagulation process in a drinking water treatment plant. These examples highlight the interest of neural techniques, when complex nonlinear phenomena are involved, but the empirical knowledge of control operators can be learned.

  20. Control of coupled oscillator networks with application to microgrid technologies

    Science.gov (United States)

    Arenas, Alex

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions-a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable syn- chronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself.

  1. Control of coupled oscillator networks with application to microgrid technologies.

    Science.gov (United States)

    Skardal, Per Sebastian; Arenas, Alex

    2015-08-01

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions-a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable synchronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself.

  2. Development and Application of Coating Weight Control Technology

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Hyoung [Dongbu Steel, Incheon (Korea, Republic of)

    2010-08-15

    Precise coating weight control is very important issue on quality and minimizing operating costs on continuous galvanizing line. These days, many steel making companies are having a new understanding of cost importance by rise raw material prices and customers requirement for cost reduction. Dongbu steel also meets these situations and decided to develop the technologies. Dongbu Steel developed Integrated coating weight control system jointly with Objective Control Ltd. and installed 2CGL and 4CGL. Several technological functions were developed and realized to achieve true hands-off operation and maximum cost benefit by combining model-based preset and dynamic prediction models. We also installed it on 1 CGL on April, 2008. This paper will present the interface, functions and application result of the integrated coating weight control system including Zn saving and coating weight uniformity.

  3. An artificial neural network controller for intelligent transportation systems applications

    Energy Technology Data Exchange (ETDEWEB)

    Vitela, J.E.; Hanebutte, U.R.; Reifman, J. [Argonne National Lab., IL (United States). Reactor Analysis Div.

    1996-04-01

    An Autonomous Intelligent Cruise Control (AICC) has been designed using a feedforward artificial neural network, as an example for utilizing artificial neural networks for nonlinear control problems arising in intelligent transportation systems applications. The AICC is based on a simple nonlinear model of the vehicle dynamics. A Neural Network Controller (NNC) code developed at Argonne National Laboratory to control discrete dynamical systems was used for this purpose. In order to test the NNC, an AICC-simulator containing graphical displays was developed for a system of two vehicles driving in a single lane. Two simulation cases are shown, one involving a lead vehicle with constant velocity and the other a lead vehicle with varying acceleration. More realistic vehicle dynamic models will be considered in future work.

  4. Advanced discrete-time control designs and applications

    CERN Document Server

    Abidi, Khalid

    2015-01-01

    This book covers a wide spectrum of systems such as linear and nonlinear multivariable systems as well as control problems such as disturbance, uncertainty and time-delays. The purpose of this book is to provide researchers and practitioners a manual for the design and application of advanced discrete-time controllers.  The book presents six different control approaches depending on the type of system and control problem. The first and second approaches are based on Sliding Mode control (SMC) theory and are intended for linear systems with exogenous disturbances. The third and fourth approaches are based on adaptive control theory and are aimed at linear/nonlinear systems with periodically varying parametric uncertainty or systems with input delay. The fifth approach is based on Iterative learning control (ILC) theory and is aimed at uncertain linear/nonlinear systems with repeatable tasks and the final approach is based on fuzzy logic control (FLC) and is intended for highly uncertain systems with heuristi...

  5. MHC-IIB filament assembly and cellular localization are governed by the rod net charge.

    Directory of Open Access Journals (Sweden)

    Michael Rosenberg

    Full Text Available BACKGROUND: Actin-dependent myosin II molecular motors form an integral part of the cell cytoskeleton. Myosin II molecules contain a long coiled-coil rod that mediates filament assembly required for myosin II to exert its full activity. The exact mechanisms orchestrating filament assembly are not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: Here we examine mechanisms controlling filament assembly of non-muscle myosin IIB heavy chain (MHC-IIB. We show that in vitro the entire C-terminus region of net positive charge, found in myosin II rods, is important for self-assembly of MHC-IIB fragments. In contrast, no particular sequences in the rod region with net negative charge were identified as important for self-assembly, yet a minimal area from this region is necessary. Proper paracrystal formation by MHC-IIB fragments requires the 196aa charge periodicity along the entire coiled-coil region. In vivo, in contrast to self-assembly in vitro, negatively-charged regions of the coiled-coil were found to play an important role by controlling the intracellular localization of native MHC-IIB. The entire positively-charged region is also important for intracellular localization of native MHC-IIB. CONCLUSIONS/SIGNIFICANCE: A correct distribution of positive and negative charges along myosin II rod is a necessary component in proper filament assembly and intracellular localization of MHC-IIB.

  6. Heterologous expression of hydrophobins RodA and RodB from Aspergillus fumigatus in host Pichia pastoris

    DEFF Research Database (Denmark)

    Pedersen, Mona Højgaard; Borodina, Irina; Frisvad, Jens Christian

    proteins with the signal sequence of alfa-mating factor from Saccharomyces cerevisia known to work well for protein secretion from P. pastoris and the pPICZB plasmids had proteins cloned with their native signal sequences. The plasmids were linearized, transformed into P. pastoris strain X33...... and transformants were selected by zeocin resistance. The presence of the RodA and RodB genes in the transformants was confirmed by colony PCR. The expression of RodA and RodB genes was induced by growing cells in culture flasks for three days in buffered complex methanol medium as protein production was dependent...

  7. Cognitive interference modeling with applications in power and admission control

    KAUST Repository

    Mahmood, Nurul Huda

    2012-10-01

    One of the key design challenges in a cognitive radio network is controlling the interference generated at coexisting primary receivers. In order to design efficient cognitive radio systems and to minimize their unwanted consequences, it is therefore necessary to effectively control the secondary interference at the primary receivers. In this paper, a generalized framework for the interference analysis of a cognitive radio network where the different secondary transmitters may transmit with different powers and transmission probabilities, is presented and various applications of this interference model are demonstrated. The findings of the analytical performance analyses are confirmed through selected computer-based Monte-Carlo simulations. © 2012 IEEE.

  8. Statistical disclosure control for microdata methods and applications in R

    CERN Document Server

    Templ, Matthias

    2017-01-01

    This book on statistical disclosure control presents the theory, applications and software implementation of the traditional approach to (micro)data anonymization, including data perturbation methods, disclosure risk, data utility, information loss and methods for simulating synthetic data. Introducing readers to the R packages sdcMicro and simPop, the book also features numerous examples and exercises with solutions, as well as case studies with real-world data, accompanied by the underlying R code to allow readers to reproduce all results. The demand for and volume of data from surveys, registers or other sources containing sensible information on persons or enterprises have increased significantly over the last several years. At the same time, privacy protection principles and regulations have imposed restrictions on the access and use of individual data. Proper and secure microdata dissemination calls for the application of statistical disclosure control methods to the data before release. This book is in...

  9. Nanosilicon properties, synthesis, applications, methods of analysis and control

    CERN Document Server

    Ischenko, Anatoly A; Aslalnov, Leonid A

    2015-01-01

    Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and pro...

  10. Component-based analysis of embedded control applications

    DEFF Research Database (Denmark)

    Angelov, Christo K.; Guan, Wei; Marian, Nicolae

    2011-01-01

    instances of reusable, executable components—function blocks (FBs). System actors operate in accordance with a timed multitasking model of computation, whereby I/O signals are exchanged with the controlled plant at precisely specified time instants, resulting in the elimination of I/O jitter. The paper......The widespread use of embedded systems requires the creation of industrial software technology that will make it possible to engineer systems being correct by construction. That can be achieved through the use of validated (trusted) components, verification of design models, and automatic...... configuration of applications from validated design models and trusted components. This design philosophy has been instrumental for developing COMDES—a component-based framework for distributed embedded control systems. A COMDES application is conceived as a network of embedded actors that are configured from...

  11. A Modular Integrated RFID System for Inventory Control Applications

    Directory of Open Access Journals (Sweden)

    Ross Bunker

    2017-01-01

    Full Text Available Recent advances in single-board computer technology have allowed for lightweight, power-efficient devices, such as the Raspberry Pi, to take the place of desktop PCs in certain applications. This has the potential to disrupt the way many current systems are structured, particularly for inventory management and control applications. In this paper, we explore the design and topology of a modular Radio frequency identification (RFID system for inventory management comprised of self-contained, autonomous scanning, and stationary control PCs in a handheld/portable configuration. While similar solutions for such a system may exist on the commercial market, this proposed development provides a template for an open source flexible, low-cost solution that can be easily expanded to meet the needs of businesses with large and small inventories.

  12. Polymer-Dispersed Liquid Crystal Films For Light Control Applications

    Science.gov (United States)

    Montgomery, G. P.

    1989-07-01

    Polymer-dispersed liquid crystal (PDLC) films, comprised of liquid crystal microdroplets dispersed in polymer matrices, are attractive for a variety of indoor and outdoor light control applications since they can be switched electrically from a light-scattering off-state to a transparent on-state. This paper reviews the electro-optic properties of PDLC films which govern their performance in such diverse applications as electronic information displays, signs, room dividers, and solar energy control in buildings and automobiles. Factors governing the operating temperature range of PDLC films will be identified and temperature-dependent transmittance and response-time characteristics of these films will be presented. Spectral transmittance characteristics will be discussed and used to determine contrast ratios of PDLC films. Dual frequency addressing of PDLC films will be demonstrated and shown to be a viable technique for increasing contrast ratio of PDLC displays. Solar attenuation properties of PDLC films will be reviewed.

  13. Application of EMG signals for controlling exoskeleton robots.

    Science.gov (United States)

    Fleischer, Christian; Wege, Andreas; Kondak, Konstantin; Hommel, Günter

    2006-12-01

    Exoskeleton robots are mechanical constructions attached to human body parts, containing actuators for influencing human motion. One important application area for exoskeletons is human motion support, for example, for disabled people, including rehabilitation training, and for force enhancement in healthy subjects. This paper surveys two exoskeleton systems developed in our laboratory. The first system is a lower-extremity exoskeleton with one actuated degree of freedom in the knee joint. This system was designed for motion support in disabled people. The second system is an exoskeleton for a human hand with 16 actuated joints, four for each finger. This hand exoskeleton will be used in rehabilitation training after hand surgeries. The application of EMG signals for motion control is presented. An overview of the design and control methods, and first experimental results for the leg exoskeleton are reported.

  14. Applications of Control Charts in Medicine and Epidemiology

    OpenAIRE

    Sego, Landon Hugh

    2006-01-01

    We consider two applications of control charts in health care. The first involves the comparison of four methods designed to detect an increase in the incidence rate of a rare health event, such as a congenital malformation. A number of methods have been proposed: among these are the Sets method, two modifications of the Sets method, and the CUSUM method based on the Poisson distribution. Many of the previously published comparisons of these methods used unrealistic assumptions or ignored i...

  15. Stabilization of Finite Automata with Application to Hybrid Systems Control

    OpenAIRE

    Kobayashi, Koichi; Imura, Jun-ichi; Hiraishi, Kunihiko

    2011-01-01

    This paper discusses the state feedback stabilization problem of a deterministic finite automaton (DFA), and its application to stabilizing model predictive control (MPC) of hybrid systems. In the modeling of a DFA, a linear state equation representation recently proposed by the authors is used. First, this representation is briefly explained. Next, after the notion of equilibrium points and stabilizability of the DFA are defined, a necessary and sufficient condition for the DFA to be stabili...

  16. Application of plausible reasoning to AI-based control systems

    Science.gov (United States)

    Berenji, Hamid; Lum, Henry, Jr.

    1987-01-01

    Some current approaches to plausible reasoning in artificial intelligence are reviewed and discussed. Some of the most significant recent advances in plausible and approximate reasoning are examined. A synergism among the techniques of uncertainty management is advocated, and brief discussions on the certainty factor approach, probabilistic approach, Dempster-Shafer theory of evidence, possibility theory, linguistic variables, and fuzzy control are presented. Some extensions to these methods are described, and the applications of the methods are considered.

  17. Resonance hybridization and near field properties of strongly coupled plasmonic ring dimer-rod nanosystem

    Energy Technology Data Exchange (ETDEWEB)

    Koya, Alemayehu Nana; Ji, Boyu; Hao, Zuoqiang; Lin, Jingquan, E-mail: linjingquan@cust.edu.cn [School of Science, Changchun University of Science and Technology, Changchun 130022 (China)

    2015-09-21

    Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing.

  18. Resonance hybridization and near field properties of strongly coupled plasmonic ring dimer-rod nanosystem

    Science.gov (United States)

    Koya, Alemayehu Nana; Ji, Boyu; Hao, Zuoqiang; Lin, Jingquan

    2015-09-01

    Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing.

  19. Determining the best technique for digestion of resin from lightning rod contaminated by-Am-241

    Energy Technology Data Exchange (ETDEWEB)

    Oshiro, Mauricio T.; Bueno, Vanessa N.; Sakata, Solange K.; Potiens Junior, Ademar J., E-mail: apotiens@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Lightning rods containing radioactive Am-241 were sold in Brazil between 1970 and 1989, when the National Nuclear Energy Commission, CNEN, through Resolution No. 4/89 suspended the authorization to manufacture and installation. As a consequence the lightning rod became radioactive waste may present risks to human health and the environment the correct management for final disposal is required. One of the products of the decontamination lightning rod is the resin used in paint, that are possibly contaminated by Am-241, a highly toxic radioisotope. The objective was to determine the best method for digestion of this of resin from lightning rod contaminated by-Am-241 for subsequent analysis. Three methods for sample digestion were evaluated: the first involving the application of H{sub 2}SO{sub 4} and H{sub 2}O{sub 2} directly on the sample; In the second method, the pre-carbonized in an oven resin were added HNO{sub 3}, H{sub 2}O{sub 2}, HF, HClO{sub 4}, and H{sub 2}O oxidants and the third method involving the addition of H{sub 2}SO{sub 4}, HNO{sub 3}, H{sub 2}O{sub 2}, HClO{sub 4} and H{sub 2}O directly to the sample. To choose the most efficient method were expressed as yield, cost and time-effective.

  20. UNICOS CPC6: Automated Code Generation for Process Control Applications

    CERN Document Server

    Fernandez Adiego, B; Prieto Barreiro, I

    2011-01-01

    The Continuous Process Control package (CPC) is one of the components of the CERN Unified Industrial Control System framework (UNICOS) [1]. As a part of this framework, UNICOS-CPC provides a well defined library of device types, amethodology and a set of tools to design and implement industrial control applications. The new CPC version uses the software factory UNICOS Application Builder (UAB) [2] to develop CPC applications. The CPC component is composed of several platform oriented plugins PLCs and SCADA) describing the structure and the format of the generated code. It uses a resource package where both, the library of device types and the generated file syntax, are defined. The UAB core is the generic part of this software, it discovers and calls dynamically the different plug-ins and provides the required common services. In this paper the UNICOS CPC6 package is introduced. It is composed of several plug-ins: the Instance generator and the Logic generator for both, Siemens and Schneider PLCs, the SCADA g...

  1. APPLICATION FEATURES OF FUZZY CONTROLLERS ON EXAMPLE OF DC MOTOR SPEED CONTROL

    Directory of Open Access Journals (Sweden)

    G. L. Demidova

    2016-09-01

    Full Text Available A prerequisite for the use of intelligent control methods, including algorithms of fuzzy logic, is increasing complexity in all industries, especially when parameters of technical systems while in operation vary in wide range. The paper provides comparative analysis of the basic types of common fuzzy direct action controllers on the example of speed control system in the DC motor drive. Design features of these types of fuzzy controllers are shown. Their comparison with traditional PI controller is carried out through the use of simulation, including the conditions of uncertainty expressed in changing of equivalent moment of inertia of the motor shaft. As a result, the conclusion about the feasibility of fuzzy PID-type controller application is made. The features of fuzzy controllers outlined in the paper can be summarized to more complex motor drive systems and to other non-linear systems that require the maintenance of any parameter within a given range.

  2. Can We Control Contaminant Transport In Hydrologic Networks? Application Of Control Theory Concepts To Watershed Management

    Science.gov (United States)

    Yeghiazarian, L.; Riasi, M. S.

    2016-12-01

    Although controlling the level of contamination everywhere in the surface water network may not be feasible, it is vital to maintain safe water quality levels in specific areas, e.g. recreational waters. The question then is "what is the most efficient way to fully/partially control water quality in surface water networks?". This can be posed as a control problem where the goal is to efficiently drive the system to a desired state by manipulating few input variables. Such problems reduce to (1) finding the best control locations in the network to influence the state of the system; and (2) choosing the time-variant inputs at the control locations to achieve the desired state of the system with minimum effort. We demonstrate that the optimal solution to control the level of contamination in the network can be found through application of control theory concepts to transport in dendritic surface water networks.

  3. Application benefits of single-phase digitally controlled vacuum reclosers

    Energy Technology Data Exchange (ETDEWEB)

    Gadbury, J.E. [Cooper Industries, South Milwaukee, WI (United States). Cooper Power Systems

    1994-12-31

    The merging of digital control technology and vacuum interruption technology has given engineers a tool that allows them to successfully coordinate parts of their system where compromises would have been made in the past. This technology has recently been used in the area of single phase reclosers. The electronic method of recloser control is more flexible, more easily adjusted and tested, and more accurate than hydraulic control. The minimum trip level chosen does not alter the maximum continuous current capacity of the recloser as with traditional hydraulic control. The sequence coordination feature greatly enhances coordination. These benefits can all be provided without the need for additional distribution transformers, arresters, or other auxiliary power supplies. Installation costs of digitally controlled reclosers remain the same as the installation costs of hydraulic reclosers. Because of the innovations, single-phase digitally-controlled vacuum reclosers lend themselves to many specific applications. These would include long rural lines where several single phase reclosers are in series, single phase taps close to the substation where potential fault currents run high, remote areas where supervisory control and status indication would most likely be utilized, and in climates with low temperature extremes.

  4. Plasmonic rod-in-shell nanoparticles for photothermal therapy.

    Science.gov (United States)

    Wang, Shanshan; Xu, Hong; Ye, Jian

    2014-06-28

    The plasmonic gold nanoparticles are promising candidates for photothermal therapy (PTT) application. The optical properties of various gold nanoparticles have been widely investigated for PTT application in the first near-infrared (NIR) window (650-950 nm). However, few studies have been reported on the nanoparticles employed in the second NIR window (1000-1350 nm) where light penetrates deeper through the tissue. Recently, a new type of plasmonic rod-in-shell (RIS) nanoparticle that can be optically responsive in the second NIR window has been reported (ACS Nano, 2013, 7, 5330). In this article, we employed an extensive numerical exploration of the optical absorption properties of the RIS particles by tuning their dimensional parameters including the core length, gap size and shell thickness. A number of favorable optical properties of the RIS nanoparticles potentially for the better PTT effect have been observed including: (1) the strong and highly tunable optical absorption in the second NIR window with a particle size less than 100 nm; (2) a larger absorption cross-section both in the first and second NIR windows over a nanorod with the same gold mass; and (3) orientation-insensitive light absorption by particles in the first NIR window due to the overlapping of the longitudinal and transverse modes. These unique optical properties imply that the RIS nanoparticles could become promising candidates for the PTT application in the first and second NIR windows.

  5. THE USE OF NITINOL RODS IN SURGICAL TREATMENT OF DEGENERATIVE SCOLIOSIS. 2.5-YEAR FOLLOW-UP

    Directory of Open Access Journals (Sweden)

    Natalia Sergeyevna Morozova

    2016-03-01

    Full Text Available ABSTRACT Objectives: To compare the outcomes of surgical treatment with lumbar fixation using nitinol rods without fusion and with standard lumbar fixation with titanium rods and interbody fusion. Methods: Treatment results of 70 patients with degenerative lumbar scoliosis aged 40 to 82 were analyzed. In all cases pedicle screws and nitinol rods with a diameter of 5.5 mm were used. Thirty patients underwent fixation at L1-S1 and 40 patients underwent fixation at L1-L5. Spinal fusion was not performed. All patients had radiography, CT and MRI performed. The results were assessed according to the Oswestry scale, SRS 22, SF 36 and VAS. The minimum follow-up period for all patients was 2.5 years. For the control group, consisting of 72 patients, pedicle fixation with titanium rods and interbody fusion in the lumbosacral region were performed. Results: The average level of deformity correction equaled 25° (10° - 38°. The analysis of X-ray and CT-scans revealed a single patient with implant instability, two patients with bone resorption around the screws and one patient with rod fractures. Functional radiography 2.5 years after surgery showed an average mobility of the lumbar spine of 21° (15° - 30°. There were no problems at the adjacent levels. Conclusions: The use of nitinol rods in spinal deformity surgery is promising. This technology is an alternative to rigid fixation. Continued gathering of clinical data and its further evaluation is necessary.

  6. Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures

    Energy Technology Data Exchange (ETDEWEB)

    Paik, S Y; Zalk, D M; Swuste, P

    2008-03-03

    Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk related to these might be assessed, and how to manage these issues in the absence of this information. This study introduces a pilot CB tool or 'CB Nanotool' that was developed specifically for characterizing the health aspects of working with engineered nanoparticles and determining the level of risk and associated controls for five ongoing nanotechnology-related operations being conducted at two Department of Energy (DOE) research laboratories. Based on the application of the CB Nanotool, four of the five operations evaluated in this study were found to have implemented controls consistent with what was recommended by the CB Nanotool, with one operation even exceeding the required controls for that activity. The one remaining operation was determined to require an upgrade in controls. By developing this dynamic CB Nanotool within the realm of the scientific information available, this application of CB appears to be a useful approach for assessing the risk of nanomaterial operations, providing recommendations for appropriate engineering controls, and facilitating the allocation of resources to the activities that most need them.

  7. FireSignal application Node for subsystem control

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, A.S., E-mail: andre.duarte@ipfn.ist.utl.p [Instituto de Plasmas e Fusao Nuclear - Instituto Superior Tecnico, Avenida Rovisco Pais 1, 1049-001 Lisbon (Portugal); Santos, B.; Pereira, T.; Carvalho, B.B.; Fernandes, H.; Neto, A. [Instituto de Plasmas e Fusao Nuclear - Instituto Superior Tecnico, Avenida Rovisco Pais 1, 1049-001 Lisbon (Portugal); Janky, F.; Cahyna, P.; Pisacka, J.; Hron, M. [Institute of Plasma Physics AS CR, Association EURATOM/IPP.CR, Za Slovankou 3, 182 00 Prague (Czech Republic)

    2010-07-15

    Modern fusion experiments require the presence of several subsystems, responsible for the different parameters involved in the operation of the machine. With the migration from the pre-programmed to the real-time control paradigm, their integration in Control, Data Acquisition, and Communication (CODAC) systems became an important issue, as this implies not only the connection to a main central coordination system, but also communications with related diagnostics and actuators. A subsystem for the control and operation of the vacuum, gas injection and baking was developed and installed in the COMPASS tokamak. These tasks are performed by dsPIC microcontrollers that receive commands from a hub computer and send information regarding the status of the operation. Communications are done in the serial protocol RS-232 through fibre optics. Java software, with an intuitive graphical user interface, for controlling and monitoring of the subsystem was developed and installed in a hub computer. In order to allow operators to perform these tasks remotely besides locally, this was integrated in the FireSignal system. Taking advantage of FireSignal features, it was possible to provide the users with, not only the same functionalities of the local application but also a similar user interface. An independent FireSignal Java Node bridges the central server and the control application. This design makes possible to easily reuse the Node for other subsystems or integrate the vacuum slow control in the other CODAC systems. The complete system, with local and remote control, has been installed successfully on COMPASS and has been in operation since April this year.

  8. FireSignal Application Node for Subsystem Control

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, A.; Santos, B.; Pereira, T.; Carvalho, B.; Fernandes, H. [Instituto de Plasmas e Fusao Nuclear - Instituto Superior Tecnico, Lisbon (Portugal); Cahyna, P.; Pisacka, J.; Hron, M. [Institute of Plasma Physics AS CR, Association EURATOM/IPP.CR, Prague (Czech Republic)

    2009-07-01

    Modern fusion experiments require the presence of several sub-systems, responsible for the different parameters involved in the operation of the machine. With the migration from the pre-programmed to the real-time control paradigm, their integration in Control, Data Acquisition, and Communication (CODAC) systems became an important issue, as this implies not only the connection to a main central coordination system, but also communications with related diagnostics and actuators. A sub-system for the control and operation of the vacuum, gas injection and baking was developed and installed in the COMPASS tokamak. These tasks are performed by 'dsPIC' micro-controllers that receive commands from a computer and send information regarding the status of the operation. Communications are done in the serial protocol RS-232 through fibre optics at speeds up to 1 Mbaud. A Java software, with an intuitive graphical user interface, for controlling and monitoring the sub-system was developed and installed in a hub computer. In order to allow operators to perform these tasks remotely besides locally, this was integrated in the FireSignal system. Taking advantage of FireSignal features, it was possible to provide the users with, not only the same functionalities of the local application but also a similar user interface. An independent FireSignal Java node bridges the central server and the control application. This design makes possible to easily reuse the node for other subsystems or integrate the vacuum slow control in the other CODAC systems. This document is composed of an abstract and a poster. (authors)

  9. A throttle-less single-rod hydraulic cylinder positioning system: Design and experimental evaluation

    Directory of Open Access Journals (Sweden)

    Ehsan Jalayeri

    2015-05-01

    Full Text Available Modern industrial tote dumpers and lifters are equipped with long-stroke single-rod hydraulic cylinders. For years, valve-controlled cylinders have been used in tote dumpers. Valve-controlled actuators are highly inefficient due to huge power losses in throttling valves. They also need a cooling system to remove the wasted heat energy from the hydraulic oil. This article introduces a low-cost throttle-less hydraulic circuit to control the single-rod cylinder of a tote dumper. The system consists of a motor-driven gear pump, an On/Off solenoid valve, to redirect the differential flow of the single-rod hydraulic cylinder and a counterbalance valve, which makes the circuit controllable for assisting loads and keeps the load in position with no effort from the hydraulic pump. Experimental results demonstrate the performance of the circuit. A test rig has been designed to simulate a lifting load. The energy efficiency of the circuit is determined by comparing a valve-controlled circuit with the proposed circuit. The proposed circuit composition is not only efficient and simple but is also accurate in terms of position response using a proportional controller. The circuit is easy to control since the only needed measurement is the displacement of the actuator. The circuit, however, does not recycle energy.

  10. Growth and characterizations of GaN micro-rods on graphene films for flexible light emitting diodes

    Directory of Open Access Journals (Sweden)

    Kunook Chung

    2014-09-01

    Full Text Available We report the growth of GaN micro-rods and coaxial quantum-well heterostructures on graphene films, together with structural and optical characterization, for applications in flexible optical devices. Graphene films were grown on Cu foil by means of chemical vapor deposition, and used as the substrates for the growth of the GaN micro-rods, which were subsequently transferred onto SiO2/Si substrates. Highly Si-doped, n-type GaN micro-rods were grown on the graphene films using metal–organic chemical vapor deposition. The growth and vertical alignment of the GaN micro-rods, which is a critical factor for the fabrication of high-performance light-emitting diodes (LEDs, were characterized using electron microscopy and X-ray diffraction. The GaN micro-rods exhibited promising photoluminescence characteristics for optoelectronic device applications, including room-temperature stimulated emission. To fabricate flexible LEDs, InxGa1–xN/GaN multiple quantum wells and a p-type GaN layer were deposited coaxially on the GaN micro-rods, and transferred onto Ag-coated polymer substrates using lift-off. Ti/Au and Ni/Au metal layers were formed to provide electrical contacts to the n-type and p-type GaN regions, respectively. The micro-rod LEDs exhibited intense emission of visible light, even after transfer onto the flexible polymer substrate, and reliable operation was achieved following numerous cycles of mechanical deformation.

  11. Application of Special Cause Control Charts to Green Sand Process

    Directory of Open Access Journals (Sweden)

    Perzyk M.

    2015-12-01

    Full Text Available Statistical Process Control (SPC based on the well known Shewhart control charts, is widely used in contemporary manufacturing industry, including many foundries. However, the classic SPC methods require that the measured quantities, e.g. process or product parameters, are not auto-correlated, i.e. their current values do not depend on the preceding ones. For the processes which do not obey this assumption the Special Cause Control (SCC charts were proposed, utilizing the residual data obtained from the time-series analysis. In the present paper the results of application of SCC charts to a green sand processing system are presented. The tests, made on real industrial data collected in a big iron foundry, were aimed at the comparison of occurrences of out-of-control signals detected in the original data with those appeared in the residual data. It was found that application of the SCC charts reduces numbers of the signals in almost all cases It is concluded that it can be helpful in avoiding false signals, i.e. resulting from predictable factors.

  12. Transcription control engineering and applications in synthetic biology

    Directory of Open Access Journals (Sweden)

    Michael D. Engstrom

    2017-09-01

    Full Text Available In synthetic biology, researchers assemble biological components in new ways to produce systems with practical applications. One of these practical applications is control of the flow of genetic information (from nucleic acid to protein, a.k.a. gene regulation. Regulation is critical for optimizing protein (and therefore activity levels and the subsequent levels of metabolites and other cellular properties. The central dogma of molecular biology posits that information flow commences with transcription, and accordingly, regulatory tools targeting transcription have received the most attention in synthetic biology. In this mini-review, we highlight many past successes and summarize the lessons learned in developing tools for controlling transcription. In particular, we focus on engineering studies where promoters and transcription terminators (cis-factors were directly engineered and/or isolated from DNA libraries. We also review several well-characterized transcription regulators (trans-factors, giving examples of how cis- and trans-acting factors have been combined to create digital and analogue switches for regulating transcription in response to various signals. Last, we provide examples of how engineered transcription control systems have been used in metabolic engineering and more complicated genetic circuits. While most of our mini-review focuses on the well-characterized bacterium Escherichia coli, we also provide several examples of the use of transcription control engineering in non-model organisms. Similar approaches have been applied outside the bacterial kingdom indicating that the lessons learned from bacterial studies may be generalized for other organisms.

  13. Numerical Simulation of Fluidic Actuators for Flow Control Applications

    Science.gov (United States)

    Vasta, Veer N.; Koklu, Mehti; Wygnanski, Israel L.; Fares, Ehab

    2012-01-01

    Active flow control technology is finding increasing use in aerospace applications to control flow separation and improve aerodynamic performance. In this paper we examine the characteristics of a class of fluidic actuators that are being considered for active flow control applications for a variety of practical problems. Based on recent experimental work, such actuators have been found to be more efficient for controlling flow separation in terms of mass flow requirements compared to constant blowing and suction or even synthetic jet actuators. The fluidic actuators produce spanwise oscillating jets, and therefore are also known as sweeping jets. The frequency and spanwise sweeping extent depend on the geometric parameters and mass flow rate entering the actuators through the inlet section. The flow physics associated with these actuators is quite complex and not fully understood at this time. The unsteady flow generated by such actuators is simulated using the lattice Boltzmann based solver PowerFLOW R . Computed mean and standard deviation of velocity profiles generated by a family of fluidic actuators in quiescent air are compared with experimental data. Simulated results replicate the experimentally observed trends with parametric variation of geometry and inflow conditions.

  14. Tunable attractions directing nonequilibrium states in dispersions of hard rods

    NARCIS (Netherlands)

    Bruggen, M.P.B. van; Lekkerkerker, H.N.W.

    2000-01-01

    The effect of attractive interactions on the phase behavior of colloidal hard rods has been studied by the addition of nonadsorbing polymer. In these rod-polymer mixtures, four pathways of phase separation can be distinguished: nucleation and growth, spinodal decomposition, aggregation, and

  15. Switch isotropic/anisotropic wettability via dual-scale rods

    Directory of Open Access Journals (Sweden)

    Yang He

    2014-10-01

    Full Text Available It is the first time to demonstrate the comparison of isotropic/anisotropic wettability between dual-scale micro-nano-rods and single-scale micro-rods. Inspired by the natural structures of rice leaf, a series of micro-nano-rods and micro-rods with different geometric parameters were fabricated using micro-fabrication technology. Experimental measured apparent contact angles and advancing and receding contact angles from orthogonal orientations were characterized. The difference of contact angles from orthogonal orientation on dual-scale rods was much smaller than those on single-scale rods in both static and dynamic situation. It indicated that the dual-scale micro-nano-rods showed isotropic wettability, while single-scale micro-rods showed anisotropic wettability. The switch of isotropic/anisotropic wettability could be illustrated by different wetting state and contact line moving. It offers a facial way to switch isotropic/anisotropic wettability of the surface via dual-scale or single-scale structure.

  16. Numerical investigation of flow past a row of rectangular rods

    Directory of Open Access Journals (Sweden)

    S.Ul. Islam

    2016-09-01

    Full Text Available A numerical study of uniform flow past a row of rectangular rods with aspect ratio defined as R = width/height = 0.5 is performed using the Lattice Boltzmann method. For this study the Reynolds number (Re is fixed at 150, while spacings between the rods (g are taken in the range from 1 to 6. Depending on g, the flow is classified into four patterns: flip-flopping, nearly unsteady-inphase, modulated inphase-antiphase non-synchronized and synchronized. Sudden jumps in physical parameters were observed, attaining either maximum or minimum values, with the change in flow patterns. The mean drag coefficient (Cdmean of middle rod is higher than the second and fourth rod for flip-flopping pattern while in case of nearly unsteady-inphase the middle rod attains minimum drag coefficient. It is also found that the Strouhal number (St of first, second and fifth rod decreases as g increases while that of other two have mixed trend. The results further show that there exist secondary interaction frequencies together with primary vortex shedding frequency due to jet in the gap between rods for 1 ⩽ g ⩽ 3. For the average values of Cdmean and St, an empirical relation is also given as a function of gap spacing. This relation shows that the average values of Cdmean and St approach to those of single rectangular rod with increment in g.

  17. Probabilistic thermo-chemical analysis of a pultruded composite rod

    NARCIS (Netherlands)

    Baran, Ismet; Tutum, Cem C.; Hattel, Jesper H.

    2012-01-01

    In the present study the deterministic thermo-chemical pultrusion simulation of a composite rod taken from the literature [7] is used as a validation case. The predicted centerline temperature and cure degree profiles of the rod match well with those in the literature [7]. Following the validation

  18. Ultrasonic detection of cracks in uniaxial glass fibre rods

    CSIR Research Space (South Africa)

    Loveday, PW

    2006-01-01

    Full Text Available propagation in the rods. The authors attempt to model the excitation and transmission of waves along undamaged as well as damaged rods in order to predict the received signals, and we compare the model results with experimental data. Specially developed...

  19. 49 CFR 236.794 - Rod, up-and-down.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Rod, up-and-down. 236.794 Section 236.794 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., up-and-down. A rod used for connecting the semaphore arm to the operating mechanism of a signal. ...

  20. Damage development in rod-on-rod impact test on 1100 pure aluminum

    Science.gov (United States)

    Iannitti, G.; Bonora, N.; Bourne, N.; Ruggiero, A.; Testa, G.

    2017-01-01

    Stress triaxiality plays a major role in the nucleation and growth of ductile damage in metals and alloys. Although, the mechanisms responsible for ductile failure are the same at low and high strain rate, in impact dynamics, in addition to time resolved stress triaxiality and plastic strain accumulation, pressure also contributes to establish the condition for ductile failure to occur. In this work, ductile damage development in 1100 commercially pure aluminum was investigated by means of rod-on-rod (ROR) impact tests. Based on numerical simulations, using a continuum damage mechanics (CDM) model that accounts for the role of pressure on damage parameters and stochastic variability of such parameters, the impact velocity for no damage, incipient and fully developed damage were estimated. ROR tests at selected velocities were performed and damage distribution and extent were investigated by sectioning of soft recovered samples. Comparison between numerical simulations and experimental results is presented and discussed.

  1. Stochastic Model Predictive Control with Applications in Smart Energy Systems

    DEFF Research Database (Denmark)

    Sokoler, Leo Emil; Edlund, Kristian; Mølbak, Tommy

    2012-01-01

    to cover more than 50% of the total consumption by 2050. Energy systems based on significant amounts of renewable energy sources are subject to uncertainties. To accommodate the need for model predictive control (MPC) of such systems, the effect of the stochastic effects on the constraints must...... function). This is convenient for energy systems, since some constraints are very important to satisfy with a high probability, whereas violation of others are less prone to have a large economic penalty. In MPC applications the control action is obtained by solving an optimization problem at each sampling......, we show that tailored interior point algorithms are well suited to handle this type of problems. Namely, by utilizing structure-exploiting methods, we implement a special-purpose solver for control of smart energy systems. The solver is compared against general-purpose implementations. As a case...

  2. Economic model predictive control theory, formulations and chemical process applications

    CERN Document Server

    Ellis, Matthew; Christofides, Panagiotis D

    2017-01-01

    This book presents general methods for the design of economic model predictive control (EMPC) systems for broad classes of nonlinear systems that address key theoretical and practical considerations including recursive feasibility, closed-loop stability, closed-loop performance, and computational efficiency. Specifically, the book proposes: Lyapunov-based EMPC methods for nonlinear systems; two-tier EMPC architectures that are highly computationally efficient; and EMPC schemes handling explicitly uncertainty, time-varying cost functions, time-delays and multiple-time-scale dynamics. The proposed methods employ a variety of tools ranging from nonlinear systems analysis, through Lyapunov-based control techniques to nonlinear dynamic optimization. The applicability and performance of the proposed methods are demonstrated through a number of chemical process examples. The book presents state-of-the-art methods for the design of economic model predictive control systems for chemical processes. In addition to being...

  3. Indirect sensorless speed control of a PMSG for wind application

    DEFF Research Database (Denmark)

    Diaz, S.A.; Silva, C.; Juliet, J.

    2009-01-01

    In this paper, the sensorless control of a permanent magnet synchronous generator (PMSG) for wind turbine applications is presented. This kind of generator has many advantages, such as: high efficiency, high power density and low maintenance requirements. To improve these characteristics...... in sensorless strategies are avoided. The sensorless scheme proposed here is based on a synchronous d-q frame phaselocked loop (PLL) for back-emf estimation, as those used in voltage phase detection for grid connected converters. The wind turbine control includes maximum power point tracking (MPPT) using...... by a squirrel cage induction machine used as wind turbine emulator and the permanent magnet generator. A control program uses a simulated wind profile and gives the speed reference for the induction machine drive, considering the turbine torque production and the inertia of the system. Experimental results...

  4. Advances and applications in sliding mode control systems

    CERN Document Server

    Zhu, Quanmin

    2015-01-01

    This book describes the advances and applications in Sliding mode control (SMC) which is widely used as a powerful method to tackle uncertain nonlinear systems. The book is organized into 21 chapters which have been organised by the editors to reflect the various themes of sliding mode control. The book provides the reader with a broad range of material from first principles up to the current state of the art in the area of SMC and observation presented in a clear, matter-of-fact style. As such it is appropriate for graduate students with a basic knowledge of classical control theory and some knowledge of state-space methods and nonlinear systems. The resulting design procedures are emphasized using Matlab/Simulink software.    

  5. Delayless acceleration measurement method for motion control applications

    Energy Technology Data Exchange (ETDEWEB)

    Vaeliviita, S.; Ovaska, S.J. [Helsinki University of Technology, Otaniemi (Finland). Institute of Intelligent Power Electronics

    1997-12-31

    Delayless and accurate sensing of angular acceleration can improve the performance of motion control in motor drives. Acceleration control is, however, seldom implemented in practical drive systems due to prohibitively high costs or unsatisfactory results of most acceleration measurement methods. In this paper we propose an efficient and accurate acceleration measurement method based on direct differentiation of the corresponding velocity signal. Polynomial predictive filtering is used to smooth the resulting noisy signal without delay. This type of prediction is justified by noticing that a low-degree polynomial can usually be fitted into the primary acceleration curve. No additional hardware is required to implement the procedure if the velocity signal is already available. The performance of the acceleration measurement method is evaluated by applying it to a demanding motion control application. (orig.) 12 refs.

  6. Explicit Nonlinear Model Predictive Control Theory and Applications

    CERN Document Server

    Grancharova, Alexandra

    2012-01-01

    Nonlinear Model Predictive Control (NMPC) has become the accepted methodology to solve complex control problems related to process industries. The main motivation behind explicit NMPC is that an explicit state feedback law avoids the need for executing a numerical optimization algorithm in real time. The benefits of an explicit solution, in addition to the efficient on-line computations, include also verifiability of the implementation and the possibility to design embedded control systems with low software and hardware complexity. This book considers the multi-parametric Nonlinear Programming (mp-NLP) approaches to explicit approximate NMPC of constrained nonlinear systems, developed by the authors, as well as their applications to various NMPC problem formulations and several case studies. The following types of nonlinear systems are considered, resulting in different NMPC problem formulations: Ø  Nonlinear systems described by first-principles models and nonlinear systems described by black-box models; �...

  7. Robust control of integrated motor-transmission powertrain system over controller area network for automotive applications

    Science.gov (United States)

    Zhu, Xiaoyuan; Zhang, Hui; Cao, Dongpu; Fang, Zongde

    2015-06-01

    Integrated motor-transmission (IMT) powertrain system with directly coupled motor and gearbox is a good choice for electric commercial vehicles (e.g., pure electric buses) due to its potential in motor size reduction and energy efficiency improvement. However, the controller design for powertrain oscillation damping becomes challenging due to the elimination of damping components. On the other hand, as controller area network (CAN) is commonly adopted in modern vehicle system, the network-induced time-varying delays that caused by bandwidth limitation will further lead to powertrain vibration or even destabilize the powertrain control system. Therefore, in this paper, a robust energy-to-peak controller is proposed for the IMT powertrain system to address the oscillation damping problem and also attenuate the external disturbance. The control law adopted here is based on a multivariable PI control, which ensures the applicability and performance of the proposed controller in engineering practice. With the linearized delay uncertainties characterized by polytopic inclusions, a delay-free closed-loop augmented system is established for the IMT powertrain system under discrete-time framework. The proposed controller design problem is then converted to a static output feedback (SOF) controller design problem where the feedback control gains are obtained by solving a set of linear matrix inequalities (LMIs). The effectiveness as well as robustness of the proposed controller is demonstrated by comparing its performance against that of a conventional PI controller.

  8. Interfacial colloidal rod dynamics: Coefficients, simulations, and analysis

    Science.gov (United States)

    Yang, Yuguang; Bevan, Michael A.

    2017-08-01

    Colloidal rod diffusion near a wall is modeled and simulated based on a constrained Stokesian dynamic model of chains-of-spheres. By modeling colloidal rods as chains-of-spheres, complete diffusion tensors are computed for colloidal rods in bulk media and near interfaces, including hydrodynamic interactions, translation-rotation coupling, and all diffusion modes in the particle and lab frames. Simulated trajectories based on the chain-of-spheres diffusion tensor are quantified in terms of typical experimental quantities such as mean squared positional and angular displacements as well as autocorrelation functions. Theoretical expressions are reported to predict measured average diffusivities as well as the crossover from short-time anisotropic translational diffusion along the rod's major axis to isotropic diffusion. Diffusion modes are quantified in terms of closed form empirical fits to model results to aid their use in interpretation and prediction of experiments involving colloidal rod diffusion in interfacial and confined systems.

  9. Study of the anti-sand sucker rod pump

    Science.gov (United States)

    Wei, Hangxin; Lv, Bingxin; Xi, Wenkui; Yi, Peng

    2017-06-01

    In order to solve the problem of sand stuck in the sucker rod pump, an anti-sand sucker rod pump is designed. The anti-sand sucker rod pump includes the conventional sucker rod pump and the swirl flow device. The sand particles can be separated from the oil in the swirl flow device, so the plunger of the sucker rod pump cannot be stuck. The motion equation of the sand particles in oil is deduced. The virtual model of the swirl flow device is built in GAMBIT software. And simulation of solid-liquid two phase flow is simulated in software FLUENT. The simulation results show that the swirl flow device can realize the sand particles separation from the oil completely. So the pump can have the effect of anti-sands.

  10. Buckling of a thin rod under cylindrical constraint

    Science.gov (United States)

    Miller, Jay; Su, Tianxiang; Wicks, Nathan; Pabon, Jahir; Bertoldi, Katia; Reis, Pedro

    2013-03-01

    We investigate the buckling and post-buckling behavior of a thin elastic rod, under cylindrical constraint, with distributed loading. Our precision model experiments consist of injecting a custom-fabricated rod into a transparent glass pipe. Under imposed velocity (leading to frictional axial loading), a portion of the initially straight rod first buckles into a sinusoidal mode and eventually undergoes a secondary instability into a helical configuration. The buckling and post-buckling behavior is found to be highly dependent on the system's geometry, namely the injected rod length and the aspect ratio of the rod to pipe diameter, as well as material parameters. We quantify the critical loads for this sequence of instabilities, contrast our results with numerical experiments and rationalize the observed behavior through scaling arguments.

  11. Visual Recognition and Its Application to Robot Arm Control

    Directory of Open Access Journals (Sweden)

    Jih-Gau Juang

    2015-10-01

    Full Text Available This paper presents an application of optical word recognition and fuzzy control to a smartphone automatic test system. The system consists of a robot arm and two webcams. After the words from the control panel that represent commands are recognized by the robot system, the robot arm performs the corresponding actions to test the smartphone. One of the webcams is utilized to capture commands on the screen of the control panel, the other to recognize the words on the screen of the tested smartphone. The method of image processing is based on the Red-Green-Blue (RGB and Hue-Saturation-Luminance (HSL color spaces to reduce the influence of light. Fuzzy theory is used in the robot arm’s position control. The Optical Character Recognition (OCR technique is applied to the word recognition, and the recognition results are then checked by a dictionary process to increase the recognition accuracy. The camera which is used to recognize the tested smartphone also provides object coordinates to the fuzzy controller, then the robot arm moves to the desired positions and presses the desired buttons. The proposed control scheme allows the robot arm to perform different assigned test functions successfully.

  12. Fractional order PID controller for improvement of PMSM speed control in aerospace applications

    Science.gov (United States)

    Saraji, Ali Motalebi; Ghanbari, Mahmood

    2014-12-01

    Because of the benefits reduced size, cost and maintenance, noise, CO2 emissions and increased control flexibility and precision, to meet these expectations, electrical equipment increasingly utilize in modern aircraft systems and aerospace industry rather than conventional mechanic, hydraulic, and pneumatic power systems. Electric motor drives are capable of converting electrical power to drive actuators, pumps, compressors, and other subsystems at variable speeds. In the past decades, permanent magnet synchronous motor (PMSM) and brushless dc (BLDC) motor were investigated for aerospace applications such as aircraft actuators. In this paper, the fractional-order PID controller is used in the design of speed loop of PMSM speed control system. Having more parameters for tuning fractional order PID controller lead to good performance ratio to integer order. This good performance is shown by comparison fractional order PID controller with the conventional PI and tuned PID controller by Genetic algorithm in MATLAB soft wear.

  13. Fractional order PID controller for improvement of PMSM speed control in aerospace applications

    Energy Technology Data Exchange (ETDEWEB)

    Saraji, Ali Motalebi [Young Researchers and Elite Club, AliAbad Katoul Branch, Islamic Azad University, AliAbad Katoul (Iran, Islamic Republic of); Ghanbari, Mahmood [Department of Electrical Engineering, AliAbad Katoul Branch, Islamic Azad University, AliAbad Katoul (Iran, Islamic Republic of)

    2014-12-10

    Because of the benefits reduced size, cost and maintenance, noise, CO2 emissions and increased control flexibility and precision, to meet these expectations, electrical equipment increasingly utilize in modern aircraft systems and aerospace industry rather than conventional mechanic, hydraulic, and pneumatic power systems. Electric motor drives are capable of converting electrical power to drive actuators, pumps, compressors, and other subsystems at variable speeds. In the past decades, permanent magnet synchronous motor (PMSM) and brushless dc (BLDC) motor were investigated for aerospace applications such as aircraft actuators. In this paper, the fractional-order PID controller is used in the design of speed loop of PMSM speed control system. Having more parameters for tuning fractional order PID controller lead to good performance ratio to integer order. This good performance is shown by comparison fractional order PID controller with the conventional PI and tuned PID controller by Genetic algorithm in MATLAB soft wear.

  14. Applications of the PID control. Temperature and position servo-control; Applications de la commande PID. Asservissement temperature et position

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, D. [Institut Universitaire de Technologie, 86 - Poitiers (France)

    2004-09-15

    The proportional integral derived function (PID) control is certainly not the most efficient but it is the most widely control used in regulation systems. The implementation of a PID regulator does not offer all adjustment possibilities of modern methods and it is in general impossible to make open-loop tests to identify the regulated system. This paper presents two concrete applications of PID control systems: one for a temperature regulation and the other for the servo-control of a mechanical system driven by a brush-less motor. The adjustment is performed using the classical momentum and frequency methods: 1 - PID control; 2 - efficiencies obtained in close loop configuration; 3 - principle of the experimental adjustment method of PID systems; 4 - experimental identification in close-loop configuration; 5 - calculation principle of a PID corrector; 6 - PID control for a class 0 system; 7 - calculation of a PID corrector for a class 1 system; 8 - PID position regulation of a brush-less motor; 9 - remarks about the numerical calculation of the control; 10 - summary of the models presented. (J.S.)

  15. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Science.gov (United States)

    Ozana, Stepan; Pies, Martin; Docekal, Tomas

    2016-06-01

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  16. Case studies on design, simulation and visualization of control and measurement applications using REX control system

    Energy Technology Data Exchange (ETDEWEB)

    Ozana, Stepan, E-mail: stepan.ozana@vsb.cz; Pies, Martin, E-mail: martin.pies@vsb.cz; Docekal, Tomas, E-mail: docekalt@email.cz [VSB-Technical University of Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Cybernetics and Biomedical Engineering, 17. listopadu 15/2172, Ostrava-Poruba, 700 30 (Czech Republic)

    2016-06-08

    REX Control System is a professional advanced tool for design and implementation of complex control systems that belongs to softPLC category. It covers the entire process starting from simulation of functionality of the application before deployment, through implementation on real-time target, towards analysis, diagnostics and visualization. Basically it consists of two parts: the development tools and the runtime system. It is also compatible with Simulink environment, and the way of implementation of control algorithm is very similar. The control scheme is finally compiled (using RexDraw utility) and uploaded into a chosen real-time target (using RexView utility). There is a wide variety of hardware platforms and real-time operating systems supported by REX Control System such as for example Windows Embedded, Linux, Linux/Xenomai deployed on SBC, IPC, PAC, Raspberry Pi and others with many I/O interfaces. It is modern system designed both for measurement and control applications, offering a lot of additional functions concerning data archiving, visualization based on HTML5, and communication standards. The paper will sum up possibilities of its use in educational process, focused on control of case studies of physical models with classical and advanced control algorithms.

  17. Probabilistic analysis of PWR and BWR fuel rod performance using the code CASINO-SLEUTH

    Energy Technology Data Exchange (ETDEWEB)

    Bull, A.J.

    1987-05-01

    This paper presents a brief description of the Monte Carlo and response surface techniques used in the code, and a probabilistic analysis of fuel rod performance in PWR and BWR applications. The analysis shows that fission gas release predictions are very sensitive to changes in certain of the code's inputs, identifies the most dominant input parameters and compares their effects in the two cases.

  18. Synthesis of Novel π-Conjugated Rod-Rod-Rod Triblock Copolymers Containing Poly(3-hexylthiophene and Polyacetylene Segments by Combination of Quasi-Living GRIM and Living Anionic Polymerization

    Directory of Open Access Journals (Sweden)

    Tomoya Higashihara

    2011-01-01

    Full Text Available The first successful synthesis of a new rod-rod-rod triblock copolymer, polyacetylene(PA-b-poly(3-hexylthiophene(P3HT-b-PA could be synthesized by a combination of quasi-living Grignard metathesis (GRIM and living anionic polymerization. We first confirmed that poly(4-tolyl vinyl sulfoxide (PTVS, which is a soluble precursor for PA, could be synthesized by living anionic polymerization in THF at −78 °C, initiated with 3-methyl-1,1-diphenylpentyllithium as the initiator in the presence of in situ-generated lithium enolate. The molecular weights (MWs and polydispersities (PDIs were well controlled (MW = 5,200–27,000, PDI = 1.10–1.22, respectively. A coil-rod-coil triblock copolymer, PTVS-b-P3HT-b-PTVS, (6,000-12,500-6,000 could also be synthesized, initiated with a P3HT-based difunctional macroinitiator in the presence of lithium enolate. GPC-RALLS and 1H NMR analyses confirmed a high degree of structural homogeneity of PTVS-b-P3HT-b-PTVS. A thermal transformation reaction of the polymer was carried out in the film state at 170 °C for 2 h to afford PA-b-P3HT-b-PA quantitatively, as monitored by TGA and FT-IR analyses. The optical and electronic properties as well as the morphological behavior of the block copolymers were investigated by UV-vis spectroscopy, conductivity measurement, and AFM observation.

  19. Innovations and applications of the VERA quality control

    Science.gov (United States)

    Mayer, D.; Steiner, A.; Steinacker, R.

    2012-10-01

    Quality control (QC) is seen today as an important scientific field to increase the value of observational data. Whereas most QC methods are linked to atmospheric modeling (being part of the data assimilation procedure), in this paper the focus is on the application of a model independent QC method based on data self consistency recently published: VERA-QC. A special challenge is the QC of data in complex terrain which requires special treatment in terms of data selection and data transformation. In this context, some special VERA-QC modules such as the consideration of significant elevation differences of adjacent stations or the consideration of transformed temperature values will be discussed. The system detects gross errors as well as biases and offers objective correction proposals (deviations) for each observation. The essential gross error detection is not only based on the statistical behavior of station specific deviations, but also on the rate of cost function reduction. Beside a two dimensional application, higher dimensionalities may also be chosen, for instance including the time coordinate. Applications and results are discussed for pressure, temperature as well as for precipitation data which needs, however, a very dense observation network. Real time application of VERA-QC allows the production of high quality fields of meteorological parameters, which can be used, e.g. for nowcasting as well as for model unbiased validation of prognostic models.

  20. Effects of Fungicides, Time of Application, and Application Method on Control of Sclerotinia Blight in Peanut

    Directory of Open Access Journals (Sweden)

    Jason E. Woodward

    2015-01-01

    Full Text Available Field studies were conducted from 2007 to 2010 to evaluate the response of peanut cultivars to different fungicides, application timings, and methods. Overall, fungicides reduced Sclerotinia blight incidence and increased pod yields when applied to susceptible and partially resistant cultivars. Disease suppression was greater when full fungicide rates were applied preventatively; however, yields between fungicide treated plots were similar. Lower levels of disease and higher yields were achieved with the partially resistant cultivar Tamrun OL07 compared to the susceptible cultivars Flavor Runner 458 and Tamrun OL 02. Despite possessing improved resistance Tamrun OL07 responded to all fungicide applications. While similar levels of disease control were achieved with broadcast or banded applications made during the day or at night, the yield response for the different application methods was inconsistent among years. A negative relationship (slope = −73.8; R2=0.73; P<0.01 was observed between final disease incidence ratings and yield data from studies where a fungicide response was observed. These studies suggest that both boscalid and fluazinam are effective at controlling Sclerotinia blight in peanuts. Alternative management strategies such as nighttime and banded applications could allow for lower fungicide rates to be used; however, additional studies are warranted.

  1. Cytocompatibility, degradation, mechanical property retention and ion release profiles for phosphate glass fibre reinforced composite rods.

    Science.gov (United States)

    Felfel, R M; Ahmed, I; Parsons, A J; Palmer, G; Sottile, V; Rudd, C D

    2013-05-01

    Fibre reinforced composites have recently received much attention as potential bone fracture fixation applications. Bioresorbable composites based on poly lactic acid (PLA) and phosphate based glass fibre were investigated according to ion release, degradation, biocompatibility and mechanical retention profiles. The phosphate based glass fibres used in this study had the composition of 40P2O5-24MgO-16CaO-16Na2O-4Fe2O3 in mol% (P40). The degradation and ion release profiles for the composites showed similar trends with the amount of sodium and orthophosphate ions released being greater than the other cations and anions investigated. This was attributed to low Dietzal's field strength for the Na(+) in comparison with Mg(2+) and Ca(2+) and breakdown of longer chain polyphosphates into orthophosphate ions. P40 composites exhibited good biocompatibility to human mesenchymal stem cells (MSCs), which was suggested to be due to the low degradation rate of P40 fibres. After 63 days immersion in PBS at 37 °C, the P40 composite rods lost ~1.1% of mass. The wet flexural, shear and compressive strengths for P40 UD rods were ~70%, ~80% and ~50% of their initial dry values after 3 days of degradation, whereas the flexural modulus, shear and compressive strengths were ~70%, ~80%, and ~65% respectively. Subsequently, the mechanical properties remained stable for the duration of the study at 63 days. The initial decrease in mechanical properties was attributed to a combination of the plasticisation effect of water and degradation of the fibre-matrix interface, with the subsequent linear behaviour being attributed to the chemical durability of P40 fibres. P40 composite rods showed low degradation and ion release rates, good biocompatibility and maintained mechanical properties similar to cortical bone for the duration of the study. Therefore, P40 composite rods have huge potential as resorbable intramedullary nails or rods. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Non-convex shape effects on the dense random packing properties of assembled rods

    Science.gov (United States)

    Meng, Lingyi; Wang, Chao; Yao, Xiaohu

    2018-01-01

    The packing of rod-like particles, which is common in physical and mathematical studies, has arisen in a variety of industrial applications. Elongation effect on the packing properties of rod-like particle has been well investigated. Besides that, rod-like particles can be easily deformed into a large amount of non-convex shapes by simply bending or assembling several particles, in which effects of non-convex deformations should also be concerned. In this work, the packing behaviors of particulate systems composed of various non-convex deformations of rod-like particles are numerically simulated via the analytical model and the relaxation algorithm. The packing configurations are further optimized using the Monte Carlo method to eliminate the local ordered structures. 8 shapes of non-convex particles including 2-dimensional and 3-dimensional particles are employed in the packing systems. Independent of aspect ratio, the dense random packing densities of identical assembled rods are up to 20% higher than those of spherocylinders and are less dependent from the specific particle shape. However, the coordination numbers of various non-convex particle packings are quite different. With a parameter of convex ratio defined, a packing composed of more non-convex particles will have a higher coordination number. This indicates that for more non-convex particle packings, there are more constraints and entanglements among neighboring particles, resulting in a more stable configuration. The nearest-neighbor contact to a centered particle in 3DX-shaped particle packings is quite different from those of other shapes, which can be identified from the location of the first peak in the radial distribution function. It is also the cause to the distinct disparities of estimated excluded volumes of non-convex particles simulated in this work.

  3. Ordinary multiplication of distributions. Application to control of economic processes

    Science.gov (United States)

    Kim, A. V.; Kormyshev, V. M.; Serova, N. B.; Fitina, L. N.; Kozhakhmetov, A. B.

    2017-11-01

    There exist many physical and economic models, which cannot be described in terms of usual functions. Such problems require application of the theory of distributions (generalized functions) (P. Antosik, J. Mikusinski, R. Sikorski, 1973; J. F. Colombeau, 1984; A.V. Kim, 2015, 1988; S.L. Sobolev, 1950; L Schwartz, 1950-1951). One of the first and the most important problems of the distribution theory consist in impossibility of defining a multiplication of distribution. The problem is so important that still is in the focus of researchers, because of various applications to nonlinear singular models. In the paper, an ordinary multiplication of generalized functions (distributions) is proposed. The obtained results are applied in a problem of control of economic processes.

  4. Wind turbine control applications of turbine-mounted LIDAR

    Science.gov (United States)

    Bossanyi, E. A.; Kumar, A.; Hugues-Salas, O.

    2014-12-01

    In recent years there has been much interest in the possible use of LIDAR systems for improving the performance of wind turbine controllers, by providing preview information about the approaching wind field. Various potential benefits have been suggested, and experimental measurements have sometimes been used to claim surprising gains in performance. This paper reports on an independent study which has used detailed analytical methods for two main purposes: firstly to try to evaluate the likely benefits of LIDAR-assisted control objectively, and secondly to provide advice to LIDAR manufacturers about the characteristics of LIDAR systems which are most likely to be of value for this application. Many different LIDAR configurations were compared: as a general conclusion, systems should be able to sample at least 10 points every second, reasonably distributed around the swept area, and allowing a look-ahead time of a few seconds. An important conclusion is that the main benefit of the LIDAR will be to enhance of collective pitch control to reduce thrust-related fatigue loads; there is some indication that extreme loads can also be reduced, but this depends on other considerations which are discussed in the paper. LIDAR-assisted individual pitch control, optimal Cp tracking and yaw control were also investigated, but the benefits over conventional methods are less clear.

  5. A control strategy for PV stand-alone applications

    Science.gov (United States)

    Slouma, S.; Baccar, H.

    2015-04-01

    This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system.

  6. Fiber optic signal collection system for primary flight control applications

    Science.gov (United States)

    Harper, Sandy L.

    1994-10-01

    The FOPMN is a fiber-optic signal collection system for primary flight control applications. An avionics bay protected electro-optic interface unit transmits light down fiber optic cable to an optical sensor housed in the harsh environment of a hydraulic actuator. The interface unit also receives the sensor's reflected pattern and calculates independent positions from the multiplexed signals. This paper discusses the FOPMN method for fiber-optically sensing and multiplexing two channels of position of a TEF actuator's main ram cylinder. Currently installed in NASA Dryden's SRA F/A-18, the FOPMN has accumulated approximately 15 hours of flight time. A performance comparison is made between the FOPMN positions and the flight control computer's feedback mechanism (the actuator LVDTs). Included is a discussion of some of the lessons learned as a result of testing the FOPMN in the lab and in flight. The FOPMN is well on its way to proving itself as a robust fiber optic system with the ability to multiplex numerous optical sensors for primary flight control. The success of the FOPMN leads to the second phase of the project--optical loop closure. Our goal for this phase is to have four FOPMN sensor channels on the main ram and/or the main control valve of the actuator to serve as the quad redundant feedback mechanism for flight control.

  7. Improved methods in neural network-based adaptive output feedback control, with applications to flight control

    Science.gov (United States)

    Kim, Nakwan

    Utilizing the universal approximation property of neural networks, we develop several novel approaches to neural network-based adaptive output feedback control of nonlinear systems, and illustrate these approaches for several flight control applications. In particular, we address the problem of non-affine systems and eliminate the fixed point assumption present in earlier work. All of the stability proofs are carried out in a form that eliminates an algebraic loop in the neural network implementation. An approximate input/output feedback linearizing controller is augmented with a neural network using input/output sequences of the uncertain system. These approaches permit adaptation to both parametric uncertainty and unmodeled dynamics. All physical systems also have control position and rate limits, which may either deteriorate performance or cause instability for a sufficiently high control bandwidth. Here we apply a method for protecting an adaptive process from the effects of input saturation and time delays, known as "pseudo control hedging". This method was originally developed for the state feedback case, and we provide a stability analysis that extends its domain of applicability to the case of output feedback. The approach is illustrated by the design of a pitch-attitude flight control system for a linearized model of an R-50 experimental helicopter, and by the design of a pitch-rate control system for a 58-state model of a flexible aircraft consisting of rigid body dynamics coupled with actuator and flexible modes. A new approach to augmentation of an existing linear controller is introduced. It is especially useful when there is limited information concerning the plant model, and the existing controller. The approach is applied to the design of an adaptive autopilot for a guided munition. Design of a neural network adaptive control that ensures asymptotically stable tracking performance is also addressed.

  8. Nanoscale optical properties of indium gallium nitride/gallium nitride nanodisk-in-rod heterostructures.

    Science.gov (United States)

    Zhou, Xiang; Lu, Ming-Yen; Lu, Yu-Jung; Jones, Eric J; Gwo, Shangjr; Gradečak, Silvija

    2015-03-24

    III-nitride based nanorods and nanowires offer great potential for optoelectronic applications such as light emitting diodes or nanolasers. We report nanoscale optical studies of InGaN/GaN nanodisk-in-rod heterostructures to quantify uniformity of light emission on the ensemble level, as well as the emission characteristics from individual InGaN nanodisks. Despite the high overall luminescence efficiency, spectral and intensity inhomogeneities were observed and directly correlated to the compositional variations among nanodisks and to the presence of structural defect, respectively. Observed light quenching is correlated to type I1 stacking faults in InGaN nanodisks, and the mechanisms for stacking fault induced nonradiative recombinations are discussed in the context of band structure around stacking faults and Fermi level pinning at nanorod surfaces. Our results highlight the importance of controlling III-nitride nanostructure growths to further reduce defect formation and ensure compositional homogeneity for optoelectronic devices with high efficiencies and desirable spectrum response.

  9. Adaptive control of energy storage systems for power smoothing applications

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2017-01-01

    for systems with multiple ESS units to realize several objectives simultaneously including SoC limiting, SoC balancing and power smoothing. Experiment is conducted considering a pulsed load profile. The results demonstrate the effectiveness of the proposal concerning the mentioned control objectives.......Energy storage systems (ESSs) are desired and widely applied for power smoothing especially in systems with renewable generation and pulsed loads. High-pass-filter (HPF) is commonly applied in those applications in which the HPF extracts the high frequency fluctuating power and uses...

  10. Optimization of Control Self Assessment Application to Minimize Fraud

    Directory of Open Access Journals (Sweden)

    Wendy Endrianto

    2016-05-01

    Full Text Available This article discussed a method that can be done by a company to minimize fraud action by applying Control Self Assessment (CSA. The study was conducted by studying literature on the topics discussed that were presented descriptively in a systematic manner through the review one by one from the initial problem to solve the problem. It can be concluded that CSA is one form of auditing practices that emphasizes anticipatory action (preventive of the act of detection (detective that the concept of modern internal audit which is carried more precise in application. It is one alternative that is most efficient and effective in reducing fraud.

  11. New technology in digital signal controllers, study & applications

    Directory of Open Access Journals (Sweden)

    Jaime Fonseca Beltrán

    2012-05-01

    Full Text Available This paper addresses the new technologies of digital signal controllers (DSC, is a general reference of the different companies making this type of device, in order that the reader has a general idea of the various products available market, highlighting thedifferences it with its predecessors, so as to identify in a clear and precise differences. This work was conceived in order to provide the user, a transition in the management of PIC ® microcontrollers general purpose, to the management of advanced microcontrollerssuch as the dsPIC., Same to be found from the use of general purpose, even those who have special features designed to more specialized applications.

  12. Applications of nonlinear systems theory to control design

    Science.gov (United States)

    Hunt, L. R.; Villarreal, Ramiro

    1988-01-01

    For most applications in the control area, the standard practice is to approximate a nonlinear mathematical model by a linear system. Since the feedback linearizable systems contain linear systems as a subclass, the procedure of approximating a nonlinear system by a feedback linearizable one is examined. Because many physical plants (e.g., aircraft at the NASA Ames Research Center) have mathematical models which are close to feedback linearizable systems, such approximations are certainly justified. Results and techniques are introduced for measuring the gap between the model and its truncated linearizable part. The topic of pure feedback systems is important to the study.

  13. Application of Risk Management for Control and Monitoring Systems

    CERN Document Server

    Grau, S; Balda, F; Chouvelon, A

    2001-01-01

    This paper presents an application of the state of the art and new trends for risk management of safety-related control and monitoring systems, currently applied in the industry. These techniques not only enable to manage safety and reliability issues but they also help in the control of quality and economic factors affected by the availability and maintenance of the system. The method includes an unambiguous definition of the system in terms of functions and a systematic analysis of hazardous situations, undesired events and possible malfunctions. It also includes the identification and quantification of the risk associated to the system. The required risk reduction is specified in terms of safety integrity levels. The safety integrity level results in requirements, preventive measures, possible improvements and recommendations to assure the satisfactory management of the risk.

  14. Remote control of the industry processes. POWERLINK protocol application

    Science.gov (United States)

    Wóbel, A.; Paruzel, D.; Paszkiewicz, B.

    2017-08-01

    The present technological development enables the use of solutions characterized by a lower failure rate, and work with greater precision. This allows you to obtain the most efficient production, high speed production and reliability of individual components. The main scope of this article was POWERLINK protocol application for communication with the controller B & R through communication Ethernet for recording process parameters. This enables control of run production cycle using an internal network connected to the PC industry. Knowledge of the most important parameters of the production in real time allows detecting of a failure immediately after occurrence. For this purpose, the position of diagnostic use driver X20CP1301 B&R to record measurement data such as pressure, temperature valve between the parties and the torque required to change the valve setting was made. The use of POWERLINK protocol allows for the transmission of information on the status of every 200 μs.

  15. Mindcontrol: A web application for brain segmentation quality control.

    Science.gov (United States)

    Keshavan, Anisha; Datta, Esha; M McDonough, Ian; Madan, Christopher R; Jordan, Kesshi; Henry, Roland G

    2017-03-30

    Tissue classification plays a crucial role in the investigation of normal neural development, brain-behavior relationships, and the disease mechanisms of many psychiatric and neurological illnesses. Ensuring the accuracy of tissue classification is important for quality research and, in particular, the translation of imaging biomarkers to clinical practice. Assessment with the human eye is vital to correct various errors inherent to all currently available segmentation algorithms. Manual quality assurance becomes methodologically difficult at a large scale - a problem of increasing importance as the number of data sets is on the rise. To make this process more efficient, we have developed Mindcontrol, an open-source web application for the collaborative quality control of neuroimaging processing outputs. The Mindcontrol platform consists of a dashboard to organize data, descriptive visualizations to explore the data, an imaging viewer, and an in-browser annotation and editing toolbox for data curation and quality control. Mindcontrol is flexible and can be configured for the outputs of any software package in any data organization structure. Example configurations for three large, open-source datasets are presented: the 1000 Functional Connectomes Project (FCP), the Consortium for Reliability and Reproducibility (CoRR), and the Autism Brain Imaging Data Exchange (ABIDE) Collection. These demo applications link descriptive quality control metrics, regional brain volumes, and thickness scalars to a 3D imaging viewer and editing module, resulting in an easy-to-implement quality control protocol that can be scaled for any size and complexity of study. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Application of COMSOL in the solution of the neutron diffusion equations for fast nuclear reactors in stationary state; Aplicacion de COMSOL en la solucion de las ecuaciones de difusion de neutrones para reactores nucleares rapidos en estado estacionario

    Energy Technology Data Exchange (ETDEWEB)

    Silva A, L.; Del Valle G, E., E-mail: evalle@ipn.mx [IPN, Escuela Superior de Fisica y Matematicas, Av. IPN s/n, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico)

    2012-10-15

    This work shows an application of the program COMSOL Multi physics Ver. 4.2a in the solution of the neutron diffusion equations for several energy groups in nuclear reactors whose core is formed by assemblies of hexagonal transversal cut as is the cas of fast reactors. A reference problem of 4 energy groups is described of which takes the cross sections which are processed by means of a program that prepares the definition of the constants utilized in COMSOL for the generic partial differential equations that this uses. The considered solution domain is the sixth part of the core which is applied frontier conditions of reflection and incoming flux zero. The discretization mesh is elaborated in automatic way by COMSOL and the solution method is one of finite elements of Lagrange grade two. The reference problem is known as the Knk with and without control rod which led to propose the calculation of the effective multiplication factor in function of the control rod fraction from a value 0 (completely inserted control rod) until the value 1 (completely extracted control rod). Besides this the reactivity was determined as well as the change of this in function of control rod fraction. The neutrons scalar flux for each energy group with and without control rod is proportioned. The reported results show a behavior similar to the one reported in other works but using the discreet ordinates S{sub 2} approximation. (Author)

  17. Dynamics of entangled rod-coil block copolymers

    Science.gov (United States)

    Wang, Muzhou; Timachova, Ksenia; Alexander-Katz, Alfredo; Likhtman, Alexei E.; Olsen, Bradley D.

    2014-03-01

    Polymer science is exploring advanced materials which combine functional domains such as proteins and semiconducting polymers with traditional flexible polymers onto the same molecule. While many studies have focused on equilibrium structure-property relationships, little is known about how the conformational restrictions of rigid domains affect dynamical phenomena such as mechanical properties, processing pathways, and self-assembly kinetics. We have recently introduced a reptation theory for entangled rod-coil block copolymers as a model for this wider class of functional polymeric materials. The theory hypothesizes that the motion of rod-coils is slowed relative to rod and coil homopolymers because of a mismatch between the curvature of the rod and coil entanglement tubes. This effect leads to activated reptation and arm retraction as two relaxation mechanisms that govern the short and long rod regimes, respectively. These results were verified by tracer diffusion measurements using molecular dynamics simulation and forced Rayleigh scattering in both the rod-coil diblock and coil-rod-coil triblock configurations. The tracer diffusion results were then compared to experimental self-diffusion measurements which require a consideration of the motion of the surrounding chains.

  18. Transcriptional Regulation of Rod Photoreceptor Homeostasis Revealed by In Vivo NRL Targetome Analysis

    Science.gov (United States)

    Hao, Hong; Kim, Douglas S.; Klocke, Bernward; Johnson, Kory R.; Cui, Kairong; Gotoh, Norimoto; Zang, Chongzhi; Gregorski, Janina; Gieser, Linn; Peng, Weiqun; Fann, Yang; Seifert, Martin; Zhao, Keji; Swaroop, Anand

    2012-01-01

    A stringent control of homeostasis is critical for functional maintenance and survival of neurons. In the mammalian retina, the basic motif leucine zipper transcription factor NRL determines rod versus cone photoreceptor cell fate and activates the expression of many rod-specific genes. Here, we report an integrated analysis of NRL-centered gene regulatory network by coupling chromatin immunoprecipitation followed by high-throughput sequencing (ChIP–Seq) data from Illumina and ABI platforms with global expression profiling and in vivo knockdown studies. We identified approximately 300 direct NRL target genes. Of these, 22 NRL targets are associated with human retinal dystrophies, whereas 95 mapped to regions of as yet uncloned retinal disease loci. In silico analysis of NRL ChIP–Seq peak sequences revealed an enrichment of distinct sets of transcription factor binding sites. Specifically, we discovered that genes involved in photoreceptor function include binding sites for both NRL and homeodomain protein CRX. Evaluation of 26 ChIP–Seq regions validated their enhancer functions in reporter assays. In vivo knockdown of 16 NRL target genes resulted in death or abnormal morphology of rod photoreceptors, suggesting their importance in maintaining retinal function. We also identified histone demethylase Kdm5b as a novel secondary node in NRL transcriptional hierarchy. Exon array analysis of flow-sorted photoreceptors in which Kdm5b was knocked down by shRNA indicated its role in regulating rod-expressed genes. Our studies identify candidate genes for retinal dystrophies, define cis-regulatory module(s) for photoreceptor-expressed genes and provide a framework for decoding transcriptional regulatory networks that dictate rod homeostasis. PMID:22511886

  19. Rhodopsin expression level affects rod outer segment morphology and photoresponse kinetics.

    Directory of Open Access Journals (Sweden)

    Clint L Makino

    Full Text Available The retinal rod outer segment is a sensory cilium that is specialized for the conversion of light into an electrical signal. Within the cilium, up to several thousand membranous disks contain as many as a billion copies of rhodopsin for efficient photon capture. Disks are continually turned over, requiring the daily synthesis of a prodigious amount of rhodopsin. To promote axial diffusion in the aqueous cytoplasm, the disks have one or more incisures. Across vertebrates, the range of disk diameters spans an order of magnitude, and the number and length of the incisures vary considerably, but the mechanisms controlling disk architecture are not well understood. The finding that transgenic mice overexpressing rhodopsin have enlarged disks lacking an incisure prompted us to test whether lowered rhodopsin levels constrain disk assembly.The structure and function of rods from hemizygous rhodopsin knockout (R+/- mice with decreased rhodopsin expression were analyzed by transmission electron microscopy and single cell recording. R+/- rods were structurally altered in three ways: disk shape changed from circular to elliptical, disk surface area decreased, and the single incisure lengthened to divide the disk into two sections. Photocurrent responses to flashes recovered more rapidly than normal. A spatially resolved model of phototransduction indicated that changes in the packing densities of rhodopsin and other transduction proteins were responsible. The decrease in aqueous outer segment volume and the lengthened incisure had only minor effects on photon response amplitude and kinetics.Rhodopsin availability limits disk assembly and outer segment girth in normal rods. The incisure may buffer the supply of structural proteins needed to form larger disks. Decreased rhodopsin level accelerated photoresponse kinetics by increasing the rates of molecular collisions on the membrane. Faster responses, together with fewer rhodopsins, combine to lower overall

  20. Transcriptional regulation of rod photoreceptor homeostasis revealed by in vivo NRL targetome analysis.

    Directory of Open Access Journals (Sweden)

    Hong Hao

    Full Text Available A stringent control of homeostasis is critical for functional maintenance and survival of neurons. In the mammalian retina, the basic motif leucine zipper transcription factor NRL determines rod versus cone photoreceptor cell fate and activates the expression of many rod-specific genes. Here, we report an integrated analysis of NRL-centered gene regulatory network by coupling chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-Seq data from Illumina and ABI platforms with global expression profiling and in vivo knockdown studies. We identified approximately 300 direct NRL target genes. Of these, 22 NRL targets are associated with human retinal dystrophies, whereas 95 mapped to regions of as yet uncloned retinal disease loci. In silico analysis of NRL ChIP-Seq peak sequences revealed an enrichment of distinct sets of transcription factor binding sites. Specifically, we discovered that genes involved in photoreceptor function include binding sites for both NRL and homeodomain protein CRX. Evaluation of 26 ChIP-Seq regions validated their enhancer functions in reporter assays. In vivo knockdown of 16 NRL target genes resulted in death or abnormal morphology of rod photoreceptors, suggesting their importance in maintaining retinal function. We also identified histone demethylase Kdm5b as a novel secondary node in NRL transcriptional hierarchy. Exon array analysis of flow-sorted photoreceptors in which Kdm5b was knocked down by shRNA indicated its role in regulating rod-expressed genes. Our studies identify candidate genes for retinal dystrophies, define cis-regulatory module(s for photoreceptor-expressed genes and provide a framework for decoding transcriptional regulatory networks that dictate rod homeostasis.