WorldWideScience

Sample records for based inspection techniques

  1. CANDU in-reactor quantitative visual-based inspection techniques

    Science.gov (United States)

    Rochefort, P. A.

    2009-02-01

    This paper describes two separate visual-based inspection procedures used at CANDU nuclear power generating stations. The techniques are quantitative in nature and are delivered and operated in highly radioactive environments with access that is restrictive, and in one case is submerged. Visual-based inspections at stations are typically qualitative in nature. For example a video system will be used to search for a missing component, inspect for a broken fixture, or locate areas of excessive corrosion in a pipe. In contrast, the methods described here are used to measure characteristic component dimensions that in one case ensure ongoing safe operation of the reactor and in the other support reactor refurbishment. CANDU reactors are Pressurized Heavy Water Reactors (PHWR). The reactor vessel is a horizontal cylindrical low-pressure calandria tank approximately 6 m in diameter and length, containing heavy water as a neutron moderator. Inside the calandria, 380 horizontal fuel channels (FC) are supported at each end by integral end-shields. Each FC holds 12 fuel bundles. The heavy water primary heat transport water flows through the FC pressure tube, removing the heat from the fuel bundles and delivering it to the steam generator. The general design of the reactor governs both the type of measurements that are required and the methods to perform the measurements. The first inspection procedure is a method to remotely measure the gap between FC and other in-core horizontal components. The technique involves delivering vertically a module with a high-radiation-resistant camera and lighting into the core of a shutdown but fuelled reactor. The measurement is done using a line-of-sight technique between the components. Compensation for image perspective and viewing elevation to the measurement is required. The second inspection procedure measures flaws within the reactor's end shield FC calandria tube rolled joint area. The FC calandria tube (the outer shell of the FC) is

  2. Principles and applications of neutron based inspection techniques

    International Nuclear Information System (INIS)

    Neutron based explosive inspection systems can detect a wide variety of substances of importance for a variety of purposes from national security threats (e.g., nuclear materials, explosives, narcotics) to customs dutiable goods, to hazardous substances to protect the environment. The inspection is generally founded on the nuclear interactions of the neutrons with the various nuclides present and the detection of resultant characteristic emissions. These can be discrete γ lines resulting from the thermal (n, γ) neutron capture process or inelastic neutron scattering (n, n'γ) occurring with fast neutrons. The two types of reactions are generally complementary. The capture process provides energetic and highly penetrating γ rays in most inorganic substances and hydrogen. Fast neutrons inelastic scattering provide relatively strong γ-ray signatures in light elements such as carbon and oxygen. In some specific important cases, unique signatures are provided by the neutron (n, γ) process in light elements such as nitrogen, where unusually high-energy γ rays are produced. This forms the basis for key explosive detection techniques. The detection of nuclear materials, both fissionable (e.g., 238U) and fissile (e.g., 235U), is generally based on the fissions induced by the probing neutrons and detecting one or more of the unique signatures of the fission process. These include prompt and delayed neutrons and prompt and delayed γ rays. These signatures are not discrete in energy (typically they are continua) but temporally and energetically significantly different from the background, thus making them readily distinguishable. The penetrability of fast neutrons as probes, and the γ rays and fission neutrons as signatures makes neutron interrogation applicable to the inspection of large conveyances such as cars, trucks, and marine containers. Neutron based inspection techniques have a broad applications. They can be used as stand-alone for complete scans of objects

  3. Principles and applications of neutron based inspection techniques

    International Nuclear Information System (INIS)

    Neutron based explosive inspection systems can detect a wide variety of substances of importance, for a variety of purposes from national security threats (e.g., nuclear materials, explosives, narcotics) to customs duties, shipment control and validation, and for protection of the environment. The inspection is generally founded on the nuclear interactions of the neutrons with the various nuclides present and the detection of resultant characteristic emissions. These can be discrete gamma lines resulting from the thermal (n,γ) neutron capture process or inelastic neutron scattering (n,n'γ) occurring with fast neutrons. The two types of reactions are generally complementary. The capture process provides energetic and highly penetrating gamma rays in most inorganic substances and in hydrogen, while fast neutron inelastic scattering provides relatively strong gamma-ray signatures in light elements such as carbon and oxygen. In some specific important cases, though, unique signatures are provided by the neutron capture process in light elements such as nitrogen, where unusually high energy gamma rays are produced. This forms the basis for key explosive detection techniques. The detection of nuclear materials, both fissionable (e.g., 238U) and fissile (e.g., 235U), are generally based on the fissions induced by the probing neutrons and detecting one or more of the unique signatures of the fission process. These include prompt and delayed neutrons and prompt and delayed gamma rays. These signatures are not discrete in energy (typically they are continua) but temporally and energetically significantly different from the background, thus making them readily distinguishable. The penetrability of fast neutrons as probes and the gamma rays and fission neutrons as signatures make neutron interrogation applicable for large conveyances such as cars, trucks and marine containers. The neutron-based techniques can be used in a variety of scenarios and operational modes. They can

  4. The role of neutron based inspection techniques in the post 9/11/01 era

    Science.gov (United States)

    Gozani, Tsahi

    2004-01-01

    Non-intrusive inspection of objects of all sizes, from luggage to shipping containers and from postal parcels to trucks is a vital component of any national security from aviation to the control of all land and sea ports of entries. The paramount importance of these inspections is more obvious now, in the post 9/11 era, as the spectrum of threats is wider and the probability of occurrence more real. The urgent need for reliable inspection underscores the key attributes they must possess: High specificity High sensitivity Provide automatic decision The technologies being currently employed in the field, such as standard X-ray, X-ray based computed tomography, and trace detection (for luggage), and X-ray or γ-ray based radiography (for containers) are inherently deficient for lacking some or all of these attributes. The neutron based technologies, on the other hand, possess all three. They provide therefore accurate, rapid and automatic detection of a wide array of threats: explosives, chemical agents, nuclear materials and devices, other hazardous materials, drugs, etc. The nuclear based techniques achieve this feat through the production of characteristic elemental gamma rays by nuclear reactions, primarily (n,γ) with thermal neutrons and (n,n 'γ) with fast neutrons. The principles and status of neutron based inspection techniques are reviewed below.

  5. Study on in-vessel ISI for JOYO. Laser based ultra sonic non-destructive inspection and manipulation technique

    International Nuclear Information System (INIS)

    This report describes the feasibility study on the in-vessel inspection technique to be applied for the experimental fast reactor JOYO. Since JOYO is a sodium cooled fast reactor and the core structure components are in high temperature and fast neutron irradiation environment, material strength yields to decrease due to heat fatigue and irradiation induced embrittlement. The present surveillance method of testing structural material mechanical property, monitoring subassembly outlet temperature and sodium leak monitoring are not sufficient to detect abnormalities with a small crack. Therefore, the direct inspection method to confirm the core structure integrity needs to be developed considering the recent innovative technology. Since the core structure has a complicated form and components under sodium are not visible, the manipulator technology is essential which has various positioning functions. The core support plate was selected to be an important inspection item, and the method which combines ultrasonic non-destructive inspection technology and manipulator technology was examined. As a result, the concept of core support plate inspection equipment under sodium condition was obtained by contacting ultrasonic sensor from inner side of the core support plate. Another concept was examined by applying laser based ultrasonic inspection technology. This method has advantage of remote control operation because of no-contacting inspection and it was confirmed to be feasible for JOYO in-vessel inspection method from viewpoint of defective detection accuracy and laser transmission ability by means of fiber cable. This is promising for in-vessel inspection without sodium draining. Based on this study, the development of in-vessel inspection equipment is continued and the proto-type will be demonstrated in JOYO. (author)

  6. Principles and applications of neutron based inspection techniques in counter terrorism

    International Nuclear Information System (INIS)

    Non-intrusive inspection of objects of all sizes, from luggage to shipping containers and from postal parcels to trucks is a vital component of any national security effort from aviation to the control of all land and sea ports of entry.The neutron-based technologies are unique in meeting all key requirements of reliable inspections. They provide accurate, rapid and objective detection of a wide array of threats explosives, chemical agents, nuclear materials and devices, other hazardous materials, drugs, etc. The technologies being currently employed in the field, such as standard x-ray, x-ray based computed tomography, and trace detection (for luggage), and x-ray or γ-ray based radiography (for containers) are inherently deficient for lacking some or all of these key attributes. The neutron-based technologies, on the other hand, possess to various high degrees all the required attributes. They achieve this feat through their penetration and the production and detection of characteristic elemental gamma rays created mainly in two nuclear reactions: (n,γ-) with thermal neutrons and (n,nNγ-) with fast neutrons produced by appropriate accelerators. These nuclear processes are the basis for several inspection technologies such as the TNA (thermal neutron analysis), FNA (fast neutron analysis), PNI (conventional microsecond pulsed neutron inspection combining the previous two), and PFNA (nanosecond pulsed fast neutron analysis). The principles of operation, applications, and advances in inspection systems will be reviewed

  7. a Holistic Approach for Inspection of Civil Infrastructures Based on Computer Vision Techniques

    Science.gov (United States)

    Stentoumis, C.; Protopapadakis, E.; Doulamis, A.; Doulamis, N.

    2016-06-01

    In this work, it is examined the 2D recognition and 3D modelling of concrete tunnel cracks, through visual cues. At the time being, the structural integrity inspection of large-scale infrastructures is mainly performed through visual observations by human inspectors, who identify structural defects, rate them and, then, categorize their severity. The described approach targets at minimum human intervention, for autonomous inspection of civil infrastructures. The shortfalls of existing approaches in crack assessment are being addressed by proposing a novel detection scheme. Although efforts have been made in the field, synergies among proposed techniques are still missing. The holistic approach of this paper exploits the state of the art techniques of pattern recognition and stereo-matching, in order to build accurate 3D crack models. The innovation lies in the hybrid approach for the CNN detector initialization, and the use of the modified census transformation for stereo matching along with a binary fusion of two state-of-the-art optimization schemes. The described approach manages to deal with images of harsh radiometry, along with severe radiometric differences in the stereo pair. The effectiveness of this workflow is evaluated on a real dataset gathered in highway and railway tunnels. What is promising is that the computer vision workflow described in this work can be transferred, with adaptations of course, to other infrastructure such as pipelines, bridges and large industrial facilities that are in the need of continuous state assessment during their operational life cycle.

  8. Optical techniques for nuclear reactor inspection

    International Nuclear Information System (INIS)

    Optical inspection techniques available and relevant to the various stages of the life cycle of a nuclear reactor are briefly reviewed. Experience in the three main types of nuclear reactor of interest to the CEGB, Magnox, AGR and PWR, is discussed. Conventional optical systems and stereoscopic viewing systems are described together with specialized and novel techniques, mainly Marchwood Engineering Laboratory's developments, which have proved valuable in tackling a variety of inspection problems. (U.K.)

  9. Risk based inspection programmes; Risikobaserte inspeksjonsprogrammer

    Energy Technology Data Exchange (ETDEWEB)

    Haugland, Haakon

    1998-07-01

    Risk based inspection is a method of selecting which parts or components of an offshore installation should be inspected and when if the resources available for inspection is to be fully exploited. By inspecting the components involving the highest risk, an optimum risk reduction is achieved. The risk level is a function of fault probability and fault consequence.

  10. Application of phased array techniques to coarse grain components inspection

    International Nuclear Information System (INIS)

    Ultrasonic inspection of cast stainless steel components from primary and auxiliary cooling circuits of 'French Nuclear Power Plant has to face with major difficulties due to the coarse grained structure of these materials. Attenuation losses and structural noise are encountered, which limits the performances of defect detection ability, mostly in terms of degraded signal-to-noise ratio and poor sensitivity. To overcome such problems, theoretical and experimental studies have been achieved at the French Atomic Energy Commission, with support from the French Institute for Radiological Protection and Nuclear Safety. Experimental studies have been performed over stainless steel specimen of known coarse structure (equi-axial grains and/or elongated grains), containing artificial reflectors (cylindrical holes and electro-eroded surface breaking notches). Those mock-ups have been inspected using contact probes of different array designs (linear or matrix splitting), and using pulse echo or dual-element techniques. Such arrays allow to control the ultrasonic beam so as to investigate different inspection angles and focusing depths. Experiments were carried out using oblique longitudinal waves, using delay laws computed by a specific model, taking account of acoustical and geometrical properties of the probes and the inspected component. In addition, specific reconstruction techniques have been investigated to enhance the signal-to-noise ratio as well as spatial resolution. These techniques are based on beam-forming summation and multi-angle inspections. Experimental results show that such techniques allow to reduce the speckle noise and to optimise the beam resolution. Those increased performances allow to detect and to size small planar defects located at the inner wall of a thick specimen, using corner and tip diffraction echoes. (authors)

  11. Development of inspection technique for CRDM housing canopy seals

    International Nuclear Information System (INIS)

    Canopy seals in CRDM (Control Rod Drive Mechanism) housing are welded seals joining stainless steel material in approximately 2 mm thickness and play an important role in leakproof for CRDM Housing. In the past, a leakage phenomenon from lower canopy seal occurred in 1984, and those from middle occurred in 1995 and 1996 respectively at domestic power plants. The cause was the stress corrosion cracking (hereafter we call it SCC) generated in the adjoining base metal of the canopy seal weld (heat affected zone). Taking the opportunity of this phenomenon, in order to detect SCC in the earlier stage and to protect leakage occurrence in advance, the technical development of the surface and volumetric inspection for the canopy seals has become an urgent task. Development and improvement for the eddy current flaw detection testing (hereafter we call it ECT) and ultrasonic flaw detection testing (hereafter we call it UT) have been conducted from 1984 up to now. This paper summarizes changes of the development of these inspection techniques and the outlines of the developed inspection techniques. (author)

  12. Proposal for inclusion of the risk based inspection technique in Regulatory Standard NR 13; Proposta de inclusao da tecnica de inspecao baseada em risco na Norma Regulamentadora NR 13

    Energy Technology Data Exchange (ETDEWEB)

    Esteves, Vinicius Teixeira; Lima, Marco Aurelio Oliveira [Det Norske Veritas Ltda. (DNV), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    In Brazil, the Regulatory Standard n. 13 (NR 13) establishes requirements for the inspection of boilers and pressure vessels which has main objective of preventing accidents with these types of equipment. Additionally, it has the Risk-Based Inspection (RBI) technique as an effective way to manage the mechanical integrity of various types of static mechanical equipment by through an inspection planning based on the risk factor. In this study, it is being proposed to include the RBI technique, in the NR 13, for the planning and definition of periods for the safety inspection of boilers and pressure vessels in order to promote an increase in the operational safety in process industries in Brazil. In this study it was carried out a critical analysis of NR 13 and RBI, and beyond that a bibliographic research of various international documents that relate the operational safety of pressurized equipment with the inspection activity, and the acceptability of RBI by governments, agencies and organizations around the world. It is considered that the inclusion and formal acceptance of RBI technique in the NR 13 must be accompanied by a rigorous control to avoid the 'trivialization' of its use and ensure the implementation rational, efficient and reliable. Finally, it was developed and suggested basic elements and minimum requirements to be inserted in the NR 13, to be attended, in order mandatory, by the companies that choose the implementation and use of the RBI technique as a tool for the planning of safety inspection of boilers and pressure vessels. It is concluded that the formal acceptance of the RBI technique in the NR 13 could aggregate much value to this standard, with regard to the prevention of accidents involving boilers or pressure vessels, and provide a technological jump to the companies that make use of RBI technique in Brazil. (author)

  13. Optimized inspection techniques and structural analysis in lifetime management

    International Nuclear Information System (INIS)

    Preservation of the option of extending the service lifetime of a nuclear power plant beyond its normal design lifetime requires correct remaining lifetime management from the very beginning of plant operation. The methodology used in plant remaining lifetime management is essentially based on the use of standard inspections, surveillance and monitoring programs and calculations, such as thermal-stress and fracture mechanics analysis. The inspection techniques should be continuously optimized, in order to be able to detect and dimension existing defects with the highest possible degree of accuracy. The information obtained during the inspection is combined with the historical data of the components: design, quality, operation, maintenance, and transients, and with the results of destructive testing, fracture mechanics and thermal fatigue analysis. These data are used to estimate the remaining lifetime of nuclear power plant components, systems and structures with the highest degree possible of accuracy. The use of this methodology allows component repairs and replacements to be reduced or avoided and increases the safety levels and availability of the nuclear power plant. Use of this strategy avoids the need for heavy investments at the end of the licensing period

  14. Development of ultrasonic immersion inspection technique for spent fuel canisters

    International Nuclear Information System (INIS)

    This report summarizes ultrasonic nondestructive testing development for metal matrix supported spent fuel disposal canisters. The work has concentated in two areas: inspection for lack of bond at the shell/matrix interface and inspection for voids in the matrix. The capabilities and limitations of these techniques have been fully established. Unbonded areas as small as 4 mm in diameter and voids 6 mm in diameter, 25 mm deep in the matrix, can readily be detected

  15. Defect sizing using automated ultrasonic inspection techniques at RNL

    International Nuclear Information System (INIS)

    RNL has developed and applied automated wide-beam pulse-echo and time-of-flight techniques with synthetic aperture processing for sizing defects in clad thick-section weldments and nozzle corner regions. These techniques were amongst those used in the four test plate inspections making up the UKAEA Defect Detection Trials. In this report a critical appraisal is given of the sizing procedures adopted by RNL in these inspections. Several factors influencing sizing accuracy are discussed and results from particular defects highlighted. The time-of-flight technique with colour graphics data display is shown to be highly effective in imaging near-vertical buried defects and underclad defects of height greater than 5 mm. Early characterisation of any identified defect from its ultrasonic response under pulse-echo inspection is seen as a desirable aid to the selection of an appropriate advanced sizing technique for buried defects. (author)

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

    International Nuclear Information System (INIS)

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

  17. Risk-based methodology for USNRC inspections

    International Nuclear Information System (INIS)

    This paper describes the development and trial applications of a risk-based methodology to enhance the inspection processes for US nuclear power plants. Objectives of risk-based methods to complement prescriptive engineering approaches in US Nuclear Regulatory Commission (USNRC) inspection programs are presented. Insights from time-dependent risk profiles of plant configurational from Individual Plant Evaluation (IPE) studies were integrated to develop a framework for optimizing inspection efforts in NRC regulatory initiatives. Lessons learned from NRC pilot applications of the risk-based methodology for evaluation of the effectiveness of operational risk management programs at US nuclear power plant sites are also discussed

  18. Inspection of reinforced concrete samples by Compton backscattering technique

    International Nuclear Information System (INIS)

    Reinforced concrete structures require frequent monitoring to ensure the concrete quality during its service life and for evaluation of in situ existing conditions. Compton backscattering of gamma rays is a nondestructive technique used for material characterization and detection of defects and inclusions in materials and can be employed on reinforced concrete. The methodology allows one-sided inspection of large structures, is relatively inexpensive and can be portable. The concept is based on detection of backscattered radiation produced from a collimated beam aimed at the sample. By measuring the spectrum of these scattered gamma rays it is possible to determine local density perturbations. In this work we used the Compton backscattering technique to locate and measure steel, defects and crushed stone inside concrete. The samples were irradiated with gamma rays from a Ø2 mm diameter collimated 241Am (100 mCi) source and the inelastically scattered photons were recorded at an angle of 135° by a high resolution CdTe semiconductor detector. Scanning was achieved by lateral movement of the sample blocks across the source and detector field of view in steps of 1 mm. A previous optimization of the experimental setup was performed with Monte Carlo simulation. The results showed that it was possible to locate inclusions and defects with Ø8 mm positioned at a depth of 20 mm below the surface of the sample. It was observed that aggregates such as crushed stone could mask defects at specific points due to high attenuation of the incident and scattered beam. - Highlights: ► Compton Backscattering was used to inspect reinforced concrete samples. ► The positioning of rebars, defects and crushed stone was achieved. ► High attenuation presented by crushed stone can mask defects at specific points

  19. Inspection of reinforced concrete samples by Compton backscattering technique

    Science.gov (United States)

    Boldo, E. M.; Appoloni, C. R.

    2014-02-01

    Reinforced concrete structures require frequent monitoring to ensure the concrete quality during its service life and for evaluation of in situ existing conditions. Compton backscattering of gamma rays is a nondestructive technique used for material characterization and detection of defects and inclusions in materials and can be employed on reinforced concrete. The methodology allows one-sided inspection of large structures, is relatively inexpensive and can be portable. The concept is based on detection of backscattered radiation produced from a collimated beam aimed at the sample. By measuring the spectrum of these scattered gamma rays it is possible to determine local density perturbations. In this work we used the Compton backscattering technique to locate and measure steel, defects and crushed stone inside concrete. The samples were irradiated with gamma rays from a Ø2 mm diameter collimated 241Am (100 mCi) source and the inelastically scattered photons were recorded at an angle of 135° by a high resolution CdTe semiconductor detector. Scanning was achieved by lateral movement of the sample blocks across the source and detector field of view in steps of 1 mm. A previous optimization of the experimental setup was performed with Monte Carlo simulation. The results showed that it was possible to locate inclusions and defects with Ø8 mm positioned at a depth of 20 mm below the surface of the sample. It was observed that aggregates such as crushed stone could mask defects at specific points due to high attenuation of the incident and scattered beam.

  20. In-vessel visual inspection system using super resolution technique

    International Nuclear Information System (INIS)

    In-Vessel Visual Inspection (IVVI) is usually conducted as indirect visual inspection with remote TV cameras. We often face the following issues in IVVI. When IVVI is conducted at narrow space in the vessel, it is difficult for inspectors to set the cameras to the best position remotely and manually. When the cameras are quickly moved to reduce hours of IVVI, the visibility becomes poor because of motion blurs. For overcoming these problems, we focused on 'Super Resolution (SR)' that is one of image processing techniques and developed a prototype system to perform the SR in IVVI. This SR technique can enhance the resolution of images with software without expensive hardware. This report shows the overview of the prototype system and its evaluation. (author)

  1. Development of FBR visual inspection technique in sodium

    International Nuclear Information System (INIS)

    Because the reactor vessel of Fast Breeder Reactor is filled with opaque liquid sodium, it is expected to develop an acoustic visual inspection technique in sodium. The acoustic 3 dimensional image processing technique and the elemental parts of the visual inspection equipment in sodium have been developed at the first stage of the in-sodium visual inspection technique development. The cross correlation processing has been applied to improve the S/N ratio in the acoustic echo that are deteriorated by wetting in sodium and the low sensitivity that are also deteriorated by rather smaller diameter to integrate the high density multiple acoustic sensors. The improvement of S/N ratio has been realized by the cross correlation between acoustic echo data that is reflected from the objects and M-series continuous wave that is transmitted from the acoustic transducer. The high speed parallel processing circuits, in which DSPs (Digital Signal Processors) are included, have been developed to realize high speed processing by employing (the circuits connected to) each of sensors in parallel. Synthetic Aperture Focussing Technique (SAFT) has been applied to the acoustic 3-dimensional image processing. The amounts of ellipsoids must be drawn into the 3-dimensional memory to compose the 3-dimensional image by SAFT. Then, a high performance work-station has been employed to deal with enormous data to compose the acoustic 3 dimensional image. Motors and cables, which can be operated under the condition of high-temperature and high-radiation environment, have been developed as the parts of the manipulator which will be used for visual inspection equipment in sodium. A prototype drive mechanism consists of the manipulator with three joints and a scanner with an arrayed acoustic sensors which a sweeps in fan-shape mechanically. The manipulatory type prototype drive mechanism and the signal processing device have been developed and tested, and the acoustic 3-dimensional image of pyramid

  2. Inspection of integrated circuits through the microfocus radiography technique

    International Nuclear Information System (INIS)

    The application of microfocus radiography technique for integrated circuits inspection is evaluated. The experiments were performed according to the international standards for micro-electronic components. In order to define the operational parameters, factors such as contrast and image definition were considered, and by varying the voltage and amperage applied to the X-ray apparatus it was tried to obtain radiographic images with an adequate resolution. the results show that this technique is a promising tool for evaluating these components. 17 refs., 16 figs., 2 tabs

  3. Development of magnetographic technique for inspecting containment welds through coatings

    International Nuclear Information System (INIS)

    The magnetographic technique was investigated for NDE of containment welds without removing paint. This technique used a magnetic yoke to magnetize a localized region of the steel containment; the leakage field from a flaw was transferred to magnetic tape placed on the containment surface and subsequently read either by means of a magnetic field sensor scanned over the tape or by the visual indications on the tape. Four specimen configurations were fabricated for the experimental evaluations. The first, a flat-plate specimen containing electric discharge machined (EDM) notches, was fabricated for initial evaluations. The three others that contained cracks consisted of one welded flat plate and two simulated containment structures representing, respectively, the longitudinal and circumferential welds in the containment wall and the 90 degree angle encountered at the base of the containment and penetrations. During the project, two types of tape were investigated, magnetic recording and Magnafilm, a tape-like material designed to produce a permanent visual indication of the magnetic leakage field from a flaw. The results show that although the magnetic recording tape did not provide sufficient sensitivity, an inspection using Magnafilm visual indications appears suitable. The latter can reliably detect containment weld cracks 6mm long through paint thicknesses up to 0.23mm and cracks longer than 6mm through paint thicknesses up to 0.38mm. Detection of cracks 6mm long through paint 0.38mm thick can be achieved by scanning the Magnafilm with a magnetic tape head; however, this approach will also tend to produce more false indications

  4. Inspection of an artificial heart by the neutron radiography technique

    International Nuclear Information System (INIS)

    The neutron radiography technique was employed to inspect an artificial heart prototype which is being developed to provide blood circulation for patients expecting heart transplant surgery. The radiographs have been obtained by the direct method with a gadolinium converter screen along with the double coated Kodak-AA emulsion film. The artificial heart consists of a flexible plastic membrane located inside a welded metallic cavity, which is employed for blood pumping purposes. The main objective of the present inspection was to identify possible damages in this plastic membrane, produced during the welding process of the metallic cavity. The obtained radiographs were digitized as well as analysed in a PC and the improved images clearly identify several damages in the plastic membrane, suggesting changes in the welding process

  5. Inspection of an artificial heart by the neutron radiography technique

    Science.gov (United States)

    Pugliesi, R.; Geraldo, L. P.; Andrade, M. L. G.; Menezes, M. O.,; Pereira, M. A. S.; Maizato, M. J. S.

    1999-11-01

    The neutron radiography technique was employed to inspect an artificial heart prototype which is being developed to provide blood circulation for patients expecting heart transplant surgery. The radiographs have been obtained by the direct method with a gadolinium converter screen along with the double coated Kodak-AA emulsion film. The artificial heart consists of a flexible plastic membrane located inside a welded metallic cavity, which is employed for blood pumping purposes. The main objective of the present inspection was to identify possible damages in this plastic membrane, produced during the welding process of the metallic cavity. The obtained radiographs were digitized as well as analysed in a PC and the improved images clearly identify several damages in the plastic membrane, suggesting changes in the welding process.

  6. Inspection of an artificial heart by the neutron radiography technique

    CERN Document Server

    Pugliesi, R; Andrade, M L G; Menezes, M O; Pereira, M A S; Maizato, M J S

    1999-01-01

    The neutron radiography technique was employed to inspect an artificial heart prototype which is being developed to provide blood circulation for patients expecting heart transplant surgery. The radiographs have been obtained by the direct method with a gadolinium converter screen along with the double coated Kodak-AA emulsion film. The artificial heart consists of a flexible plastic membrane located inside a welded metallic cavity, which is employed for blood pumping purposes. The main objective of the present inspection was to identify possible damages in this plastic membrane, produced during the welding process of the metallic cavity. The obtained radiographs were digitized as well as analysed in a PC and the improved images clearly identify several damages in the plastic membrane, suggesting changes in the welding process.

  7. Vibrational Based Inspection Of A Steel Mast

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    1994-01-01

    The aim of this paper is to present the results from a research project concerning vibrational based inspection of a 20 meter high steel mast containing well defined damages. Introductory analyses dealing with among other things evaluation of potential damage indicators and determination of...

  8. IEC-based neutron generator for security inspection system

    International Nuclear Information System (INIS)

    Use of a combined X-ray and neutron source for security inspections based on Inertial Electrostatic Confinement (IEC) fusion is discussed. Current inspection systems typically use X-ray techniques, but thermal neutron analysis (TNA) and fast neutron analysis (FNA), allow expanded detection of certain types of explosives. The integrated unit proposed here uses three separate IEC sources producing 14 and 2.45 MeV neutrons plus soft X-rays. This combination allows multiple detection methods with the composite signal analysis being done by a fuzzy logic system, significantly reducing false signals. (author)

  9. Leather inspection based on wavelets

    OpenAIRE

    Sobral, João Luís Ferreira

    2005-01-01

    This paper presents a new methodology to detect leather defects, based on the wavelet transform. The methodology uses a bank of optimised filters, where each filter is tuned to one defect type. Filter shape and wavelet sub-band are selected based the maximisation of the ratio between features values on defect regions and on normal regions. The proposed methodology can detect defects even when small features variations are present, which are not detect by generic texture classification techniq...

  10. Inspection-Repair based Availability Optimization of Distribution Systems using Teaching Learning based Optimization

    Science.gov (United States)

    Tiwary, Aditya; Arya, L. D.; Arya, Rajesh; Choube, S. C.

    2015-03-01

    This paper describes a technique for optimizing inspection and repair based availability of distribution systems. Optimum duration between two inspections has been obtained for each feeder section with respect to cost function and subject to satisfaction of availability at each load point. Teaching learning based optimization has been used for availability optimization. The developed algorithm has been implemented on radial and meshed distribution systems. The result obtained has been compared with those obtained with differential evolution.

  11. Development of visual inspection technique under sodium in FBR

    International Nuclear Information System (INIS)

    The reactor vessel of a fast breeder reactor (FBR) is filled with optically opaque liquid sodium. Therefore, the ultrasonic imaging technique is useful for inspecting in-vessel structures in sodium. We have developed a high-speed and high-resolution three-dimensional image processing technique. For imaging in the sodium, a two-dimensional matrix transducer and the M-series transmitting signal were used. Cross-correlation processing between the transmitted signal and received signal was used to enhance the S/N ratio. Image synthesis also attempts enhancement of resolution by means of the synthetic aperture focusing (SAFT). It has been confirmed that clear and high-resolution three-dimensional ultrasonic images are acquired at a distance of 0.8m in the in-water visualizing test. (author)

  12. Procedure for the determination of gap and base ground surface configurations beneath the bottom plate of storage tanks using neutron gauging inspection techniques : including radiation safety procedure and emergency procedure

    International Nuclear Information System (INIS)

    The procedure is intended for the neutron gauging inspection of gap between the bottom plate and the foundation of bulk storage tanks, which potentially exhibit uneven sinking of the bottom plate and the foundation. Its describes the requirements for the performance of neutron back scattered inspection techniques (or radiometric non-destructive evaluation techniques), using an isotopic neutron source associated with neutron detecting systems, to detect and size the gap between the bottom plate and the foundations as well as to quantify the presence of hydrogenous materials (e.g. oil or water) underneath the bottom plate. This procedure is not only outline the requirements for the neutron gauging inspection, but also describes the requirements which shall be taken into account in formulating the radiation safety and emergency procedures for the neutron gauging inspection works

  13. Principles and status of neutron-based inspection technologies

    Science.gov (United States)

    Gozani, Tsahi

    2011-06-01

    Nuclear based explosive inspection techniques can detect a wide range of substances of importance for a wide range of objectives. For national and international security it is mainly the detection of nuclear materials, explosives and narcotic threats. For Customs Services it is also cargo characterization for shipment control and customs duties. For the military and other law enforcement agencies it could be the detection and/or validation of the presence of explosive mines, improvised explosive devices (IED) and unexploded ordnances (UXO). The inspection is generally based on the nuclear interactions of the neutrons (or high energy photons) with the various nuclides present and the detection of resultant characteristic emissions. These can be discrete gamma lines resulting from the thermal neutron capture process (n,γ) or inelastic neutron scattering (n,n'γ) occurring with fast neutrons. The two types of reactions are generally complementary. The capture process provides energetic and highly penetrating gamma rays in most inorganic substances and in hydrogen, while fast neutron inelastic scattering provides relatively strong gamma-ray signatures in light elements such as carbon and oxygen. In some specific important cases unique signatures are provided by the neutron capture process in light elements such as nitrogen, where unusually high-energy gamma ray is produced. This forms the basis for key explosive detection techniques. In some cases the elastically scattered source (of mono-energetic) neutrons may provide information on the atomic weight of the scattering elements. The detection of nuclear materials, both fissionable (e.g., 238U) and fissile (e.g., 235U), are generally based on the fissions induced by the probing neutrons (or photons) and detecting one or more of the unique signatures of the fission process. These include prompt and delayed neutrons and gamma rays. These signatures are not discrete in energy (typically they are continua) but temporally

  14. Inspection of pipeline girth welds with ultrasonic phased array technique

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A novel automatic ultrasonic system used for the inspection of pipeline girth welds is developed, in which a linear phased array transducer using electronic scan is adopted. Optimal array parameters are determined based on a mathematical model of acoustic field for linear phased array derived from Huygens' principle. The testing method and the system structure are introduced. The experimental results show that the phased array transducer system has the same detectability as that of conventional ultrasonic transducer system, but the system architecture can be simplified greatly, and the testing flexibility and the testing speed can be improved greatly.

  15. Use of artificial intelligence techniques for visual inspection systems prototyping. Application to magnetoscopy

    International Nuclear Information System (INIS)

    The automation of visual inspection is a complex task that requires collaboration between experts, for example inspection specialist, vision specialist. on-line operators. Solving such problems through prototyping promotes this collaboration: the use of a non specific programming environment allows rapid, concrete checking of method validity, thus leading incrementally to the final system. In this context, artificial intelligence techniques permit easy, extensible, and modular design of the prototype, together with heuristic solution building. We define and achieve the SPOR prototyping environment, based on object-oriented programming and rules-basis managing. The feasibility and the validity of an heuristic method for automated visual inspection in fluoroscopy have been proved through prototyping in SPOR. (author)

  16. Risk-based inspection in the context of nuclear power plants

    International Nuclear Information System (INIS)

    Nuclear power plant owners have to consider several aspects like safety, availability, costs and radiation exposure during operation of nuclear power plants. They also need to demonstrate to regulatory bodies that risk assessment and inspection planning processes are being implemented in effective and appropriate manner. Risk-Based Inspection (RBI) is a methodology that, unlike time-based inspection, involves a quantitative assessment of both failure probability and consequence associated with each safety-related item. A correctly implemented RBI program classifies individual equipment by its risks and prioritizes inspection efforts based on this classification. While in traditional deterministic approach, the inspection frequencies are constant, in the RBI approach the inspection interval for each item depends on the risk level. Regularly, inspection intervals from RBI result in risk levels lower or equal than deterministic inspection intervals. According to the literature, RBI solutions improve integrity and reduce costs through a more effective inspection. Risk-Informed In-service Inspection (RI-ISI) is the equivalent term used in the nuclear area. Its use in nuclear power plants around world is briefly reviewed in this paper. Identification of practice methodologies for performing risk-based analyses presented in this paper can help both Brazilian nuclear power plant operator and regulatory body in evaluating the RI-ISI technique feasibility as a tool for optimizing inspections within nuclear plants. (author)

  17. Inspection technique for internal defects in glasses using machine vision

    International Nuclear Information System (INIS)

    The necessity for the automatic inspection system of glasses is highly increased in high-quality glass industry. In this paper, machine vision approach to inspect the internal defect in glass is tried. Our new inspection algorithm which considers the optical characteristics of internal defects shows good experimental performance.

  18. In service inspection of pipes based on risk methods

    International Nuclear Information System (INIS)

    The politics of the Nuclear Regulatory Commission (by its initials in English NRC) of the United States of America on the use of the Probabilistic Safety Analysis (PSA) in activities of nuclear regulation it foments the use of this analysis technique to improve the decisions making, to reduce the unnecessary work in maintenance aspects, inspection and tests and to improve the regulatory efficiency. The inspection programs in service (ISI by its initials in English) developed by the American Society of Mechanical Engineers (by its initials in English ASME) it has been the one primary mechanism to prove the mechanical equipment in plants of nuclear energy, these programs indeed have been carried out in plants of nuclear energy by more of two decades. Their purpose is to identify the conditions, such as indications of cracks that are precursory of flights and ruptures which violate the integrity principles of the pressure frontier. The inspection in service activities include ultrasonic tests, surface tests and penetrating liquids test, also activities that include the scaffolds construction, removal of insulations and welding polishing. The inspections in service every 18 months during the times outside of service are executed. One of the objectives is to lower the costs of the inspections during the times outside of service and to reduce the exposure to the radiation by part of the personnel during these times out for inspections, while it is increased or it maintains the personnel's safety and the reliability. As part of the methodology a pipe segment is selected for which a fault in any point has the same consequences, being calculated the fault probability of the tube using the dimensions of the segment. In this work the inspection in service methodology is applied based on risk to an aspersion system of low pressure of the Laguna Verde Nucleo electric Central. For this system a reduction in the number of welding to inspect of 103 to only 15 is obtained

  19. Reliability-Based Inspection Planning for Structural Systems

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    A general model for reliability-based optimal inspection and repair strategies for structural systems is described. The total expected costs in the design lifetime is minimized with the number of inspections, the inspection times and efforts as decision variables. The equivalence of this model with...... a preposterior analysis from statistical decision theory is discussed. It is described how information obtained by an inspection can be used in a repair decision. Stochastic models for inspection, measurement and repair actions are presented. The general model is applied for inspection and repair...

  20. Performance-based inspection and maintenance strategies

    Energy Technology Data Exchange (ETDEWEB)

    Vesely, W.E.

    1995-04-01

    Performance-based inspection and maintenance strategies utilize measures of equipment performance to help guide inspection and maintenance activities. A relevant measure of performance for safety system components is component unavailability. The component unavailability can also be input into a plant risk model such as a Probabilistic Risk Assessment (PRA) to determine the associated plant risk performance. Based on the present and projected unavailability performance, or the present and projected risk performance, the effectiveness of current maintenance activities can be evaluated and this information can be used to plan future maintenance activities. A significant amount of information other than downtimes or failure times is collected or can be collected when an inspection or maintenance is conducted which can be used to estimate the component unavailability. This information generally involves observations on the condition or state of the component or component piecepart. The information can be detailed such as the amount of corrosion buildup or can be general such as the general state of the component described as {open_quotes}high degradation{close_quotes}, {open_quotes}moderate degradation{close_quotes}, or {open_quotes}low degradation{close_quotes}. Much of the information collected in maintenance logs is qualitative and fuzzy. As part of an NRC Research program on performance-based engineering modeling, approaches have been developed to apply Fuzzy Set Theory to information collected on the state of the component to determine the implied component or component piecepart unavailability. Demonstrations of the applications of Fuzzy Set Theory are presented utilizing information from plant maintenance logs. The demonstrations show the power of Fuzzy Set Theory in translating engineering information to reliability and risk implications.

  1. Risk based inspection for atmospheric storage tank

    Science.gov (United States)

    Nugroho, Agus; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

    2016-04-01

    Corrosion is an attack that occurs on a metallic material as a result of environment's reaction.Thus, it causes atmospheric storage tank's leakage, material loss, environmental pollution, equipment failure and affects the age of process equipment then finally financial damage. Corrosion risk measurement becomesa vital part of Asset Management at the plant for operating any aging asset.This paper provides six case studies dealing with high speed diesel atmospheric storage tank parts at a power plant. A summary of the basic principles and procedures of corrosion risk analysis and RBI applicable to the Process Industries were discussed prior to the study. Semi quantitative method based onAPI 58I Base-Resource Document was employed. The risk associated with corrosion on the equipment in terms of its likelihood and its consequences were discussed. The corrosion risk analysis outcome used to formulate Risk Based Inspection (RBI) method that should be a part of the atmospheric storage tank operation at the plant. RBI gives more concern to inspection resources which are mostly on `High Risk' and `Medium Risk' criteria and less on `Low Risk' shell. Risk categories of the evaluated equipment were illustrated through case study analysis outcome.

  2. Verification of Remote Inspection Techniques for Reactor Internal Structures of Liquid Metal Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Lee, Jae Han

    2007-02-15

    The reactor internal structures and components of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection as major in-service inspection (ISI) methods of reactor internal structures and components. Reactor internals of LMR can not be visually examined due to opaque liquid sodium. The under-sodium viewing techniques using an ultrasonic wave should be applied for the visual inspection of reactor internals. Recently, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium inspection. In this study, visualization technique, ranging technique and monitoring technique have been suggested for the remote inspection of reactor internals by using the waveguide sensor. The feasibility of these remote inspection techniques using ultrasonic waveguide sensor has been evaluated by an experimental verification.

  3. Application of ultrasonic phased array technique for inspection of stud bolts in nuclear reactor vessel

    International Nuclear Information System (INIS)

    The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Cracks initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It take too much time to inspect stud bolt by using conventional ultrasonic technique. In addition, there were numerous spurious signal reflected from every thread. In this study, the advanced ultrasonic phased array technique was introduced for inspect stud bolts. The phased array technique provide fast inspection and high detectability of defects. There are sector scanning and linear scanning method in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated.

  4. Coke drums inspection and evaluation using stress and strain analysis techniques

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Marcio Issamu [Tricom Tecnologia e Servicos de Manutencao Industrial Ltda., Piquete, SP (Brazil); Samman, Mahmod [Houston Engineering Solutions, Houston, TX (United States); Tinoco, Ediberto Bastos; Marangone, Fabio de Castro; Silva, Hezio Rosa da; Barcelos, Gustavo de Carvalho [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Coke drums deform due to a complex combination of mechanical and thermal cyclic stresses. Bulges have progressive behavior and represent the main maintenance problem related to these drums. Bulge failure typically result in through-wall cracks, leaks, and sometimes fires. Such failures generally do not represent a great risk to personnel. Repairs needed to maintain reliability of these vessels might require extensive interruption to operation which in turn considerably impacts the profitability of the unit. Therefore the condition, progression and severity of these bulges should be closely monitored. Coke drums can be inspected during turnaround with 3D Laser Scanning and Remote Visual Inspection (RVI) tools, resulting in a detailed dimensional and visual evaluation of the internal surface. A typical project has some goals: inspect the equipment to generate maintenance or inspection recommendations, comparison with previous results and baseline data. Until recently, coke drum structural analysis has been traditionally performed analyzing Stress Concentration Factors (SCF) thought Finite Element Analysis methods; however this technique has some serious technical and practical limitations. To avoid these shortcomings, the new strain analysis technique PSI (Plastic Strain Index) was developed. This method which is based on API 579/ ASME FFS standard failure limit represents the state of the art of coke drum bulging severity assessment has an excellent correlation with failure history. (author)

  5. Generic service water system risk-based inspection guide

    International Nuclear Information System (INIS)

    The risk-based inspection guide is intended to supplement US Nuclear Regulatory Commission (NRC) Temporary Instruction 2515/115, ''Service Water System Operational Performance Inspection (SWSOPI).'' The purpose of this guide is to assist NRC inspection team leaders and team members to prioritize inspection items and refine inspection plans so their inspections will address those elements that dominate the risk associated with the service water system. This generic document presents risk insights obtained from probabilistic risk assessments and historical operating experience. Because it is intended to assist inspections at all commercial US power reactors (which have wide variations in service water system designs), some items may not be applicable to every plant. Where possible, the risk significance of the potential inspection items has been related to particular characteristics of plant design or environmental conditions so that inspectors can determine which items may be applicable to a specific plant

  6. Risk based inspection experience from the European chemical- and petrochemical industries

    International Nuclear Information System (INIS)

    As an inspection vendor with 60 years of experience and with more than 25 years of experience as manufacturer of the Automated Ultrasonic NDT systems, the P-scan systems, FORCE Institute is continuously analysing the market for NDT. This is done to assure that both the equipment product line and the service mix provided by FORCE Institute are meeting the requirements from the industry today and in the future. The concept of Risk Based Inspection Programmes were adopted early by the offshore industry and has in the recent years been adopted by many other industries as a reliable and cost efficient way of maintaining a production facility. A Risk/Reliability Based Inspection Programme is a 'living organism' that constantly needs information if it shall be of any value and NDT information is only one type of information that is required. The NDT information required is normally related to corrosion/base material information and weld integrity information. NDT as an integrated part of a plants maintenance system is, in Europe, currently influenced by the following tendencies which all are related to 'Risk Based Inspection': · Increased use of Base-Line Inspections · Reduction in the use of repeated inspections(qualitative- instead of quantitative Inspections). · Inspection results are fed directly into the plant maintenance system. · Fitness-for-Purpose acceptance criteria instead of conventional acceptance criteria. As repeatability and accuracy is a key issue for the data, automated ultrasonic inspection is increasingly used as an alternative to manual ultrasonic inspection, but due to the physical size of most automated ultrasonic inspection systems the gain in productivity has not been as significant as the gain in repeatability and accuracy. In this paper some of FORCE Institute's practical experiences with examinations carried out in connection with Risk Based Inspection is used to illustrate the above described tendencies. Not only examples using automated

  7. A Robot Based Automatic Paint Inspection System

    Science.gov (United States)

    Atkinson, R. M.; Claridge, J. F.

    1988-06-01

    The final inspection of manufactured goods is a labour intensive activity. The use of human inspectors has a number of potential disadvantages; it can be expensive, the inspection standard applied is subjective and the inspection process can be slow compared with the production process. The use of automatic optical and electronic systems to perform the inspection task is now a growing practice but, in general, such systems have been applied to small components which are accurately presented. Recent advances in vision systems and robot control technology have made possible the installation of an automated paint inspection system at the Austin Rover Group's plant at Cowley, Oxford. The automatic inspection of painted car bodies is a particularly difficult problem, but one which has major benefits. The pass line of the car bodies is ill-determined, the surface to be inspected is of varying surface geometry and only a short time is available to inspect a large surface area. The benefits, however, are due to the consistent standard of inspection which should lead to lower levels of customer complaints and improved process feedback. The Austin Rover Group initiated the development of a system to fulfil this requirement. Three companies collaborated on the project; Austin Rover itself undertook the production line modifications required for body presentation, Sira Ltd developed the inspection cameras and signal processing system and Unimation (Europe) Ltd designed, supplied and programmed the robot system. Sira's development was supported by a grant from the Department of Trade and Industry.

  8. Vibrational Based Inspection of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Rytter, Anders

    University of Aalborg from 1988 to 1991. Secondly, a research project, In-Field Vibration Based Inspection of Civil Engineering Structures, which has been performed as a pilot project by the Consulting Engineers Rambøll, Hannemann and Højlund in cooperation with the department of Building Technology and......The thesis has been written in relation to two different research projects. Firstly, an offshore test programme, Integrated Experimental/Numerical Analysis of the Dynamic behavior of offshore structures, which was performed at the department of Building Technology and Structural Engineering at the...... Structural Engineering at the University of Aalborg since the beginning of 1992. Both projects have been supported by the Danish Technical Research Council. Further, the first mentioned project was supported by the Danish Energy Agency. Their financial support is gratefully acknowledged....

  9. Nondestructive inspection of chemical warfare based on API-TOF

    International Nuclear Information System (INIS)

    Background: Real-time, fast, accurate, nondestructive inspection (NDI) and quantitative analysis for chemical warfare are very imperative for chemical defense, anti-terror and nation security. Purpose: Associated Particles Technique (APT)/Neutron Time of Flight (TOF) has been developed for non-invasive inspection of sealed containers with chemical warfare agents. Methods: A prototype equipment for chemical warfare is consisted of an APT neutron generator with a 3×3 matrix of semiconductor detectors of associated alpha-particles, the shielding protection of neutron and gamma-ray, arrayed NaI(Tl)-based detectors of gamma-rays, fully-digital data acquisition electronics, data analysis, decision-making software, support platform and remote control system. Inelastic scattering gamma-ray pulse height spectra of sarin, VX, mustard gas and adamsite induced by 14-MeV neutron are measured. The energies of these gamma rays are used to identify the inelastic scattering elements, and the intensities of the peaks at these energies are used to reveal their concentrations. Results: The characteristic peaks of inelastic scattering gamma-ray pulse height spectra show that the prototype equipment can fast and accurately inspect chemical warfare. Conclusion: The equipment can be used to detect not only chemical warfare agents but also other hazardous materials, such as chemical/toxic/drug materials, if their chemical composition is in any way different from that of the surrounding materials. (authors)

  10. Study on flaw detection and evaluation technique for turbine rotor disc using ultrasonic inspection

    International Nuclear Information System (INIS)

    Rim or web part of the turbine rotor disc can be inspected by magnetic test(MT) or penetration test(PT) because of easy accessibility to them. but, unless disc is separated from a rotor, above NDT inspection of hub, keyway part and bore surface is not applicable because of difficult accessibility to them. MT method which has been used for inspection of the LP turbine disc, should be replaced by a new method as it has caused an increase of the manpower followed by blade separation and prolonged shut-down periods. So, ultrasonic inspection that can be inspected promptly and elucidated crack size, is urgently required for a disc, and can not but depend on this method. However, due to complexity of their shape and structure, and unestablishment of inspection technique, ultrasonic inspection for a disc has many difficulties such as inspection method, flaw evaluation and signal analysis etc. Thus, in this study, ultrasonic inspection technique to detect and assess flows occurred in turbine rotor disc was developed, and also their inspection procedure was established for guarantee of safety and reliability on turbine for a power plant.

  11. Risk Based Inspection Planning of Ageing Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Ersdal, Gerhard

    2008-01-01

    system aspects are considered incl. assessment of the acceptable annual probability of failure for one component dependent on the number of critical components. Information obtained from inspection of one component can be used not only to update the inspection plan for that component, but also for other...... nearby components. An example indicates that a high degree of correlation between the uncertain parameters in different components is needed in order to obtain substantial information which can be used in inspection planning. Fatigue failure of one (or more) components does not necessary imply total...

  12. Inspection Based Evaluation of a Danish Road Bridge

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper it is shown how an inspection-based evaluation of a Danish road bridge may be performed using the BRIDGE1 and BRIDGE2 bridge management systems produced within the EC-supported research programme "Assessment of Performance and Optimal Strategies for Inspection and Maintenance of Con...... Concrete Structures using Reliability Based Expert Systems"....

  13. Benefits of Risk Based Inspection Planning for Offshore Structures

    DEFF Research Database (Denmark)

    Straub, D.M.; Goyet, J.; Sørensen, John Dalsgaard;

    2006-01-01

    The economical benefits of applying risk-based inspection planning (RBI) for offshore structures subject to fatigue are evaluated based on experiences from past industrial projects. To this end, the factors influencing the cost of inspection, repair and failure of structures are discussed and...... financial benefit of RBI is assessed....

  14. Development and validation of nondestructive inspection techniques for composite doubler repairs on commercial aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Roach, D.; Walkington, P.

    1998-05-01

    Composite doublers, or repair patches, provide an innovative repair technique which can enhance the way aircraft are maintained. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is possible to bond a single boron-epoxy composite doubler to the damaged structure. In order for the use of composite doublers to achieve widespread use in the civil aviation industry, it is imperative that methods be developed which can quickly and reliably assess the integrity of the doubler. In this study, a specific composite application was chosen on an L-1011 aircraft in order to focus the tasks on application and operation issues. Primary among inspection requirements for these doublers is the identification of disbonds, between the composite laminate and aluminum parent material, and delaminations in the composite laminate. Surveillance of cracks or corrosion in the parent aluminum material beneath the doubler is also a concern. No single nondestructive inspection (NDI) method can inspect for every flaw type, therefore it is important to be aware of available NDI techniques and to properly address their capabilities and limitations. A series of NDI tests were conducted on laboratory test structures and on full-scale aircraft fuselage sections. Specific challenges, unique to bonded composite doubler applications, were highlighted. An array of conventional and advanced NDI techniques were evaluated. Flaw detection sensitivity studies were conducted on applicable eddy current, ultrasonic, X-ray and thermography based devices. The application of these NDI techniques to composite doublers and the results from test specimens, which were loaded to provide a changing flaw profile, are presented in this report. It was found that a team of these techniques can identify flaws in composite doubler installations well before they reach critical size.

  15. Thermal wave imaging techniques for inspection of plywood materials

    Science.gov (United States)

    Mulaveesala, Ravibabu; Venkata Nagarjuna, P.; Ravi, Dadda; Amarnath, Muniyappa

    2012-06-01

    Infrared non-destructive testing and evaluation (IRNDT&E) is an emerging approach for materials characterization due to its capability to test wide variety of solid materials such as metals, composites and semiconductors of industrial interest. Further it supports thorough inspection and evaluation by its unique remote and fast and whole field testing capabilities. Wood is one of the most commonly used house hold building material it has both structural and decorative applications. It is used both in natural and processed form like ply wood, veneer, ply-board etc. Defects like knots, worm track, delaminations, glue smear etc. influences its in-service capabilities. Even though various non-destructive methods such as optical, ultrasonic and radiography are commonly used to inspect wooden materials, infrared imaging has its own advantage due to its safe, whole field inspection capabilities. This paper describes the applicability of the transient thermal wave imaging (TWI) method for inspection of ply wood. This paper highlights applicability of transient pulsed thermal imaging approach for finding out the hidden defects. Capability of the proposed method and its defect detection capabilities have been highlighted through experimental results.

  16. Application of Ultrasonic inspection Technique on Fuel Rod Seam Weld

    International Nuclear Information System (INIS)

    As of the end of March, 1996, 26 BWR power plants of which station capacity has reached up to 23,000 GW in total are in commercial operation in Japan, Japan Nuclear Fuel (JNF), a BWR fuel fabricator in Japan, has supplied fuels to those power plants for 25 years. This paper presents refinement of inspection technology applied to enhance completeness of fuel rod welding at JNF, which has cumulatively produced approximately 50,000 fuel bundles to the date in Japan. In this operation, TIG method has been employed for plug to tube welding of fuel rod, and X-ray radiography was formerly applied as nondestructive testing (NDT) means in order to verify weld integrity of every fuel rod. As there was limited capabilities of X-ray radiography such as shooting time and direction, and also inspection of fuel rod weld integrity is one of key characteristics of regulatory inspection according to the law, JNF has developed and applied more reliable and effective probe rotation type ultrasonic method. This paper presents refinement of inspection technology applied to enhance completeness of fuel rod welding at JNF

  17. Heat Exchanger Tube Inspection of Nuclear Power Plants using IRIS Technique

    International Nuclear Information System (INIS)

    Inspection of heat exchange tubing include steam generator of nuclear power plant mostly performed with eddy current method. Recently, various inspection technique is available such as remote field eddy current, flux leakage and ultrasonic methods. Each of these techniques has its merits and limitations. Electromagnetic techniques are very useful to locate areas of concern but sizing is hard because of the difficult interpretation of an electric signature. On the other hand, ultrasonic methods are very accurate in measuring wall loss damage, and are reliable for detecting cracks. Additionally ultrasound methods is not affected by support plates or tube sheets and variation of electrical conductivity or permeability. Ultrasound data is also easier to analyze since the data displayed is generally the remaining wall thickness. It should be emphasized that ultrasound is an important tool for sizing defects in tubing. In addition, it can be used in situations where eddy current or remote field eddy current is not reliable, or as a flaw assessment tool to supplement the electromagnetic data. The need to develop specialized ultrasonic tools for tubing inspection was necessary considering the limitations of electromagnetic techniques to some common inspection problems. These problems the sizing of wall loss in carbon steel tubes near the tube sheet or support plate, sizing internal erosion damage, and crack detection. This paper will present an IRIS(Internal Rotating Inspection System) ultrasonic tube inspection technique for heat exchanger tubing in nuclear power plant and verify inspection reliability for artificial flaw embedded to condenser tube

  18. Synthetic Aperture Focusing Technique in Ultrasonic Inspection of Coarse Grained Materials

    International Nuclear Information System (INIS)

    Experience from the ultrasonic inspection of nuclear power plants has shown that large focused transducers are relatively effective in suppressing grain (structure) noise. Operation of a large focused transducer can be thought of as an integration (coherent summation) of individual beams reflected from the target and received by individual points at the transducer surface. Synthetic aperture focusing technique (SAFT), in its simplest version mimics an acoustic lens used for focusing beams at a desired point in the region of interest. Thus, SAFT should be able to suppress the grain noise in the similar way as the focused transducer does. This report presents the results of investigation of SAFT algorithms applied for post-processing of ultrasonic data acquired in inspection of coarse grained metals. The performance of SAFT in terms of its spatial (cross-range) resolution and grain noise suppression is studied. The evaluation is made based on the experimental data obtained from the ultrasonic inspection of test specimens with artificial defects (side drilled holes). SAFT algorithms for both contact and immersion mode are introduced and experimentally verified

  19. A PLM-based automated inspection planning system for coordinate measuring machine

    Science.gov (United States)

    Zhao, Haibin; Wang, Junying; Wang, Boxiong; Wang, Jianmei; Chen, Huacheng

    2006-11-01

    With rapid progress of Product Lifecycle Management (PLM) in manufacturing industry, automatic generation of inspection planning of product and the integration with other activities in product lifecycle play important roles in quality control. But the techniques for these purposes are laggard comparing with techniques of CAD/CAM. Therefore, an automatic inspection planning system for Coordinate Measuring Machine (CMM) was developed to improve the automatization of measuring based on the integration of inspection system in PLM. Feature information representation is achieved based on a PLM canter database; measuring strategy is optimized through the integration of multi-sensors; reasonable number and distribution of inspection points are calculated and designed with the guidance of statistic theory and a synthesis distribution algorithm; a collision avoidance method is proposed to generate non-collision inspection path with high efficiency. Information mapping is performed between Neutral Interchange Files (NIFs), such as STEP, DML, DMIS, XML, etc., to realize information integration with other activities in the product lifecycle like design, manufacturing and inspection execution, etc. Simulation was carried out to demonstrate the feasibility of the proposed system. As a result, the inspection process is becoming simpler and good result can be got based on the integration in PLM.

  20. Vision Based Autonomous Robotic Control for Advanced Inspection and Repair

    Science.gov (United States)

    Wehner, Walter S.

    2014-01-01

    The advanced inspection system is an autonomous control and analysis system that improves the inspection and remediation operations for ground and surface systems. It uses optical imaging technology with intelligent computer vision algorithms to analyze physical features of the real-world environment to make decisions and learn from experience. The advanced inspection system plans to control a robotic manipulator arm, an unmanned ground vehicle and cameras remotely, automatically and autonomously. There are many computer vision, image processing and machine learning techniques available as open source for using vision as a sensory feedback in decision-making and autonomous robotic movement. My responsibilities for the advanced inspection system are to create a software architecture that integrates and provides a framework for all the different subsystem components; identify open-source algorithms and techniques; and integrate robot hardware.

  1. Disposal technique inspect of France's uranium mine and mill facilities decommissioning

    International Nuclear Information System (INIS)

    Invited by Linet F.L., the director of France Atomic Energy Committee, China disposal technique inspection delegation on uranium mine and mill facilities decommissioning (UMMFD) inspected France's UMMFD disposal techniques on Oct. 7∼30, 1997. Introduces in detail the disposal Standard, environmental radiation monitoring and evaluation, covering experiment and decommissioning disposal procedure, and gives certain case of France's uranium mine and mill facilities decommissioning disposal

  2. Application of reliability techniques to prioritize BWR [boiling water reactor] recirculation loop welds for in-service inspection

    International Nuclear Information System (INIS)

    In January 1988 the US Nuclear Regulatory Commission issued Generic Letter 88-01 together with NUREG-0313, Revision 2, ''Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping,'' to implement NRC long-range plans for addressing the problem of stress corrosion cracking in boiling water reactor piping. NUREG-0313 presents guidelines for categorizing BWR pipe welds according to their SCC condition (e.g., presence of known cracks, implementation of measures for mitigating SCC) as well as recommended inspection schedules (e.g., percentage of welds inspected, inspection frequency) for each weld category. NUREG-0313 does not, however, specify individual welds to be inspected. To address this issue, the Lawrence Livermore National Laboratory developed two recommended inspection samples for welds in a typical BWR recirculation loop. Using a probabilistic fracture mechanics model, LLNL prioritized loop welds on the basis of estimated leak probabilities. The results of this evaluation indicate that riser welds and bypass welds should be given priority attention over other welds. Larger-diameter welds as a group can be considered of secondary importance compared to riser and bypass welds. A ''blind'' comparison between the probability-based inspection samples and data from actual field inspections indicated that the probabilistic analysis generally captured the welds which the field inspections identified as warranting repair or replacement. Discrepancies between the field data and the analytic results can likely be attributed to simplifying assumptions made in the analysis. The overall agreement between analysis and field experience suggests that reliability techniques -- when combined with historical experience -- represent a sound technical basis on which to define meaningful weld inspection programs. 13 refs., 8 figs., 5 tabs

  3. IEC-Based Neutron Generator for Security Inspection System

    International Nuclear Information System (INIS)

    Large nuclear reactors are widely employed for electricity power generation, but small nuclear radiation sources can also be used for a variety of industrial/government applications. In this paper we will discuss the use of a small neutron source based on Inertial Electrostatic Confinement (IEC) of accelerated deuterium ions. There is an urgent need of highly effective detection systems for explosives, especially in airports. While current airport inspection systems are strongly based on X-ray technique, neutron activation including Thermal Neutron Analysis (TNA) and Fast Neutron Analysis (FNA) is powerful in detecting certain types of explosives in luggage and in cargoes. Basic elements present in the explosives can be measured through the (n, n'?) reaction initiated by fast neutrons. Combined with a time-of-flight technique, a complete imaging of key elements, hence of the explosive materials, is obtained. Among the various neutron source generators, the IEC is an ideal candidate to meet the neutron activation analysis requirements. Compared with other accelerators and radioisotopes such as 252Cf, the IEC is simpler, can be switched on or off, and can reliably produce neutrons with minimum maintenance. Theoretical and experimental studies of a spherical IEC have been conducted at the University of Illinois. In a spherical IEC device, 2.54-MeV neutrons of ∼108 n/s via DD reactions over recent years or 14-MeV neutrons of ∼2x1010 n/s via DT reactions can be obtained using an ion gun injection technique. The possibility of the cylindrical IEC in pulsed operation mode combining with pulsed FNA method would also be discussed. In this paper we examine the possibility of using an alternative cylindrical IEC configuration. Such a device was studied earlier at the University of Illinois and it provides a very convenient geometry for security inspection. However, to calculate the neutron yield precisely with this configuration, an understanding of the potential wall

  4. Development of an ultrasonic inspection technique for the dovetail of turbine rotor disks

    International Nuclear Information System (INIS)

    Non-destructive inspection of steam turbine rotor disks has become more important if high reliability of power plants is to be maintained. Defects in the rotor may be produced by a material secular change or increased number of start-stop operations, and they may cause unexpected trouble in the plant. The authors have been developing an ultrasonic inspection technique with a shorter inspection time for the dovetail of turbine rotor disks. This method allows the blades to be kept on the dovetail. In this report, they developed an inspection system to detect radial defects, which propagate in an axial radial direction. It has the following two features: use of the reflection at the dovetail for detection of hidden defects; and combination of single and double probe methods. In this inspection, the probes are set at the position and angle at which reflection waves from the notched part have maximum power. The probes are moved on the fixed rotor disks by a vehicle. The defects are detected by a change in received power of the single and double probe methods during probe scanning. The inspection time is about one-fourth that of magnetic particle inspection (MT), which requires blades to be removed from the dovetail. In application of this technique to inspection of artificial defects in a full size dovetail, a radial defect of 0.5 mm height could be detected. The defect detection sensitivity had its maximum value when the incidence angle at the dovetail was equal to 43--45 degree

  5. Ultrasonic inspection of composite hydrogen reservoirs using frequency diversity techniques

    International Nuclear Information System (INIS)

    During their service, cryogenic tanks are subjected to both hydrostatic and hygrothermic stresses. This can have as a consequence the initiation of the propagation of cracks within the structure of the material. Nevertheless, the analysis of ultrasonic signals collected during the inspection of composite materials must be dealt with carefully because of the presence of a strong background noise due to the reinforcement. This background noise results mostly from the interferences between the waves diffracted on the reinforcement. The target echo and the noise in which it is embedded both have the same frequency bandwidth. Thus we cannot use conventional linear filters to improve the signal-to-noise ratio

  6. Distributed heterogeneous inspecting system and its middleware-based solution

    Institute of Scientific and Technical Information of China (English)

    黄理灿; 吴朝晖; 潘云鹤

    2003-01-01

    There are many cases when an organization needs to monitor the data and operations of its supervised departments, especially those departments which are not owned by this organization and are managed by their own information systems. Distributed Heterogeneous Inspecting System (DHIS) is the system an organization uses to monitor its supervised departments by inspecting their information systems. In DHIS, the inspected systems are generally distributed, heterogeneous, and constructed by different companies. DHIS has three key processes-abstracting core data sets and core operation sets, collecting these sets, and inspecting these collected sets. In this paper, we present the concept and mathematical definition of DHIS, a metadata method for solving the interoperability, a security strategy for data transferring, and a middleware-based solution of DHIS. We also describe an example of the inspecting system at WENZHOU custom.

  7. Distributed heterogeneous inspecting system and its middleware-based solution

    Institute of Scientific and Technical Information of China (English)

    黄理灿; 吴朝晖; 潘云鹤

    2003-01-01

    There are many cases when an organization needs to monitor the data and operations of its super-vised departments, especially those departments which are not owned by this organization and are managed by their own information systems. Distributed Heterogeneous Inspecting System (DHIS) is the system an organization uses to monitor its supervised departments by inspecting their information systems. In DHIS, the inspected systems are generally distributed, heterogeneous, and constructed by different companies. DHIS has three key processes-abstracting core data sets and core operation sets, collecting these sets, and inspecting these collected sets. In this paper, we present the concept and mathematical definition of DHIS, a metadata method for solving the interoperability, a security strategy for data transferring, and a middleware-based solution of DHIS. We also describe an example of the inspecting system at WENZHOU custom.

  8. Optimal Risk-Based Inspection Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Rangel-Ramirez, Jose G.; Sørensen, John Dalsgaard

    2008-01-01

    monopile, tripod or jacket type foundation. Monopiles are at present the most typical foundation, but tripods and jackets are expected to be used in the future at larger water depths. The Support structures are facing deterioration processes such as fatigue and corrosion. To 'control' this deterioration......, inspection and maintenance activities are developed. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod types of wind turbine support structures. Based oil risk-based inspection planning methods used for oil & gas installations, a framework for...

  9. Optimal Risk-Based Inspection Planning for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2008-01-01

    monopile, tripod or jacket type foundation. Monopiles are at present the most typical foundation, but tripods and jackets are expected to be used in the future at larger water depths. The support structures are facing deterioration processes such as fatigue and corrosion. To ‘control' this deterioration......, inspection and maintenance activities are developed. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod types of wind turbine support structures. Based on risk-based inspection planning methods used for oil & gas installations, a framework for...

  10. Risk-based inspection--Development of guidelines

    International Nuclear Information System (INIS)

    Effective inservice inspection programs can play a significant role in minimizing equipment and structural failures. Most of the current inservice inspection programs for light water reactor (LWR) nuclear power plant components are based on experience and engineers' qualitative judgment. These programs include only an implicit consideration of risk, which combines the probability of failure of a component under its operation and loading conditions and the consequences of such failure, if it occurs. This document recommends appropriate methods for establishing a risk-based inspection program for LWR nuclear power plant components. The process has been built from a general methodology (Volume 1) and has been expanded to involve five major steps: defining the system; evaluating qualitative risk assessment results; using this and information from plant probabilistic risk assessments to perform a quantitative risk analysis; selecting target failure probabilities; and developing an inspection program for components using economic decision analysis and structural reliability assessment methods

  11. A practical approach to risk-based inservice inspection in U.S. nuclear power plants

    International Nuclear Information System (INIS)

    To provide guidelines for practical implementation of risk-based ISI, EPRI sponsored work to develop evaluation procedures and criteria for defining risk-based inservice inspection programs for nuclear power plant piping. These procedures and criteria include efficient means to identify risk significant piping segments, inspection locations, and available inspection techniques. These procedures were applied in a pilot study to assess the feasibility of successfully implementing risk-based inservice inspection programs at nuclear plants. The results from the pilot study indicate that implementation of risk-based inservice inspection programs can reduce the cost and radiation exposure associated with inservice inspection, while maintaining a high level of safety. The list of references provides additional details of these procedures and plant-specific applications. Also, an EPRI technical report has been published to document these procedures. Software has been developed to support and fully document this procedure. Additional development is adding an expert system to the present data base system. The approach compares well to approaches used (or being considered) in other industries and can easily be adapted to these other industries and to address economic and personnel safety in addition to public safety measures

  12. Ultrasonic turbine shaft inspection using the synthetic aperture focussing technique (SAFT)

    International Nuclear Information System (INIS)

    Ultrasonic imaging techniques developed for turbine shaft inspection result in a two-dimensional image of the defect distribution inside the specimen. It is shown, how the effect of reflectors outside of the image plane lead to misinterpretation of the reflector positions. The expansion of the two-dimensional imaging technique to three-dimensions will help to overcome these problems. (orig.)

  13. Inspection Workshop-6: OSI Technologies: Methodologies and Techniques for Application

    Energy Technology Data Exchange (ETDEWEB)

    Krioutchenkov, V.; Shchukin, V.; Sweeney, J.J.

    2000-09-14

    On-Site Inspection (OSI) Workshop-6 met 26-30 June 2000 in Vienna, hosted by the Provisional Technical Secretariat (PTS) of the CTBT Organization. The purpose of the workshop was to provide guidance on OSI Operational Manual (OM) development for Working Group B (WGB) of the CTBT preparatory Commission (PrepCom) in the general areas of equipment and logistics. The two main sessions of this workshop, titled ''OSI Equipment: Development of Functional and Operational Requirements, Specifications and Application Procedures'' and ''OSI Logistics: Continued Work on Standing Arrangements, Status of Inspectors and Support Equipment Issues'' reflected this focus. For this workshop, the schedule of work was divided into two parts: The first half of the week were sessions with formal paper presentations and discussion; the latter half of the week used two smaller subgroups to focus on and discuss separately equipment and logistics issues. Drawing heavily on the results of the five previous workshops, these subgroups produced material to be considered by Working Group B. This provisional material is intended to advance the process of equipment definition and procurement and establish procedures for logistics that can be incorporated into the OSI Operational Manual. The participants agreed that using subgroups in this workshop was an especially effective mechanism for discussion of different expert opinion on technical issues, and that having access to material presented at the previous five OSI workshops was particularly valuable.

  14. Development of ultrasonic techniques for feeder cracking inspection at Gentilly-2

    International Nuclear Information System (INIS)

    PLGS has been affected by cracks found in PHT systems. A feeder was found to leak in Dec. 1996 and the cause was a crack in outlet feeder S08. The cracking was attributed to the fact that the channel was unlocked at both ends. This incident was thought to be isolated until another leak was found in March 2001. Feeder K16 was the leaker and an extensive ultrasonic inspection has found two more cracked feeders. Gentilly-2 is a CANDU 6 that was built at the same time and using several identical suppliers as PLGS. Gentilly-2 was alerted of a possible aging mechanism and because of the similarities of both stations, had to respond rapidly to inspect its reactor. Gentilly-2 sent a team to learn the PLGS inspection method and to perform a similar campaign in April 2001. Further improvements to the inspection method were undertaken by Hydro-Quebec. The inspection could be improved and at the same time dose reduced significantly by developing a remote scanner that can deliver multiple transducers and execute the scanning without the help of a technician. The robotic development was done in 2002 and use on the reactor in June and September 2003. This paper covers the development of the feeder cracking inspection technique from the method developed by PLGS, the industry cracking procedure V18, and improvements done by Gentilly-2 to mechanize the inspection. (author)

  15. Proceedings of the Joint EC, OECD, IAEA Specialists Meeting on NDE Techniques Capability Demonstration and Inspection Qualification

    International Nuclear Information System (INIS)

    The 1997 International Specialists Meeting on NDE Techniques Capability Demonstration and Inspection Qualification was intended to provide an international forum for the discussion of recent developments, results and experience with NDE techniques capability demonstration and inspection qualification methods. The meeting provided an opportunity to compare and assess the qualification principles as proposed or applied by the American Performance Demonstration Initiative, the European Network on Inspection Qualification and the IAEA in its proposed guidelines specific to WWERs. The meeting addressed, in terms of state of the art, the capability demonstration of NDE procedures applied to the major nuclear reactor components. Special emphasis was placed on NDE techniques qualification to detect and size flaws in order to assure structural integrity during plant design life or beyond. National positions or experience were presented showing the typical variety of applications of one or two general principles or methodologies in agreement with national legal and traditional aspects. Experience developed by national qualification bodies and by pilot studies were rich in information concerning the difficulties which were encountered during the studies. Risk Based Inspection concepts were explained due to their relevance with the setting of the ISI objectives and therefore the level of qualification required for each situation considered

  16. Monte Carlo parametric studies of neutron interrogation with the Associated Particle Technique for cargo container inspections

    Science.gov (United States)

    Deyglun, Clément; Carasco, Cédric; Pérot, Bertrand

    2014-06-01

    The detection of Special Nuclear Materials (SNM) by neutron interrogation is extensively studied by Monte Carlo simulation at the Nuclear Measurement Laboratory of CEA Cadarache (French Alternative Energies and Atomic Energy Commission). The active inspection system is based on the Associated Particle Technique (APT). Fissions induced by tagged neutrons (i.e. correlated to an alpha particle in the DT neutron generator) in SNM produce high multiplicity coincidences which are detected with fast plastic scintillators. At least three particles are detected in a short time window following the alpha detection, whereas nonnuclear materials mainly produce single events, or pairs due to (n,2n) and (n,n'γ) reactions. To study the performances of an industrial cargo container inspection system, Monte Carlo simulations are performed with the MCNP-PoliMi transport code, which records for each neutron history the relevant information: reaction types, position and time of interactions, energy deposits, secondary particles, etc. The output files are post-processed with a specific tool developed with ROOT data analysis software. Particles not correlated with an alpha particle (random background), counting statistics, and time-energy resolutions of the data acquisition system are taken into account in the numerical model. Various matrix compositions, suspicious items, SNM shielding and positions inside the container, are simulated to assess the performances and limitations of an industrial system.

  17. Risk-based inspection in ASME Section XI

    International Nuclear Information System (INIS)

    By 1970 the first edition of the ASME Code Section XI, Inservice Inspection of Nuclear Reactor Coolant Systems was published. From its inception, the Section XI inservice inspection scope was based on a fundamental risk-based selection process. In other words the inservice inspection scope included components where the consequences of a pressure boundary failure were high. Once the consequence significant system boundaries were established, inspections would then be performed at locations believed to be most susceptible service induced failure. Current Section XI requirements require that inspection locations be selected on the basis of peak stress and fatigue usage values contained in the Design Reports. These original stress calculations were designed to qualify a design and assure that the plant would provide reliable service throughout its design life. For the most part, the fatigue usage values in these reports do not provide an accurate measure of service life. As service history has demonstrated, the use of Design Report stresses and fatigue usage values can be misleading. The Section XI ISI inspection requirements have always been intended to focus inspections at those locations in the plant that pose the greater risk to reactor safety. This fundamental principle behind the Section XI inspection requirements has guided Section XI since its inception. However, today Utility resources are limited. The move in many states to deregulate utilities and growing competition from independent power producers is challenging Owners to reduce operating and maintenance cost without sacrificing safety. These programs should allow plants to focus limited resources on those locations where damage mechanisms are active and consequences are high. This will provide for efficient use of plants resources and improve safety

  18. Singular Stokes-polarimetry as new technique for metrology and inspection of polarized speckle fields

    Science.gov (United States)

    Soskin, Marat S.; Denisenko, Vladimir G.; Egorov, Roman I.

    2004-08-01

    Polarimetry is effective technique for polarized light fields characterization. It was shown recently that most full "finger-print" of light fields with arbitrary complexity is network of polarization singularities: C points with circular polarization and L lines with variable azimuth. The new singular Stokes-polarimetry was elaborated for such measurements. It allows define azimuth, eccentricity and handedness of elliptical vibrations in each pixel of receiving CCD camera in the range of mega-pixels. It is based on precise measurement of full set of Stokes parameters by the help of high quality analyzers and quarter-wave plates with λ/500 preciseness and 4" adjustment. The matrices of obtained data are processed in PC by special programs to find positions of polarization singularities and other needed topological features. The developed SSP technique was proved successfully by measurements of topology of polarized speckle-fields produced by multimode "photonic-crystal" fibers, double side rubbed polymer films, biomedical samples. Each singularity is localized with preciseness up to +/- 1 pixel in comparison with 500 pixels dimensions of typical speckle. It was confirmed that network of topological features appeared in polarized light field after its interaction with specimen under inspection is exact individual "passport" for its characterization. Therefore, SSP can be used for smart materials characterization. The presented data show that SSP technique is promising for local analysis of properties and defects of thin films, liquid crystal cells, optical elements, biological samples, etc. It is able discover heterogeneities and defects, which define essentially merits of specimens under inspection and can"t be checked by usual polarimetry methods. The detected extra high sensitivity of polarization singularities position and network to any changes of samples position and deformation opens quite new possibilities for sensing of deformations and displacement of

  19. Key Techniques of the X-ray Inspection Real-time Imaging Pipeline Robot

    Institute of Scientific and Technical Information of China (English)

    Deng Zongquan(邓宗全); Xu Fengping; Zhang Xiaohua; Chen Hongjun

    2004-01-01

    This paper presents a robotic system for weld-joint inspection of the big-caliber pipeline, which is developed for the purpose of being utilized as automation platform for X-ray real-time imaging inspection technique (RTIIT). The robot can perform autonomous seeking and locating of weld-seam position in-pipe, and under the control of synchro-follow control technique it can accomplish the technologic task of weld inspection. The robotic system is equipped with a small focal spot and directional beam X-ray tube, so the higher definition image of weld-seam can be obtained. Several key techniques about the robotic system developed are also explained in detail. Its construction is outlined.

  20. Development of multifunction laser welding head (3). Surface inspection technique by laser-ultrasonics

    International Nuclear Information System (INIS)

    Multifunction laser welding head has been developed. The head is able to perform not only underwater laser welding as repair, but also laser peening as preventive maintenance and laser ultrasonic testing as inspection. For inspection with multifunction laser welding head, a new method of visualized weld defects in water by laser-ultrasonics has developed. To detect and visualize a surface of weld metal with welding bead, the authors have developed a new detection method by leaky wave induced by interaction with surface acoustic waves and defects. Furthermore, developing Synthetic Aperture Focus Technique (SAFT) for visualized inspection surface 2-dimensionally, we achieve the inspection result alike Penetrant Testing (PT) despite underwater environment with multifunction laser welding head. (author)

  1. Quality assurance and inspection techniques in use at Babcock and Wilcox

    International Nuclear Information System (INIS)

    When Babcock and Wilcox reentered the aluminum research reactor fuel element business, most of the equipment, processes and techniques were provided by our customers. Some of the equipment, both manufacturing and inspection, has been in use since the beginning of the program and dates back some 20 years. Babcock and Wilcox has applied the expertise and technology gained from our naval fuel program in several areas of research, fabrication and inspection to update this equipment. Areas of improvement are capacitance non-contact gaging, min-clad gage evaluation and the future of real time x-ray systems. With production and inspection costs rising, Babcock and Wilcox has also initiated alternative possibilities for inspecting components at lower costs and increased precision

  2. Automated inspection of pwr steam generator tubes with eddy current and ultrasonic techniques

    International Nuclear Information System (INIS)

    This paper reports that with a view to improve reactor safety and availability, the steam generator tubes of the seven Belgian nuclear plants are inspected, since 1985, with an automated non destructive examination system. Both eddy current and ultrasonic techniques are applied in function of the degradation phenomenon and the related plugging limit. The five years experience has shown that significant advantages in terms of increased accuracy and lower cost are related to the use of dedicated probes and a high level of automation. Owing to specialized data management, a preliminary field report is available one hour after the last tube has been inspected. Despite these capabilities, the inspection system uses commercially available instruments and desktop computers linked through a local area network. It demonstrates that improved inspection efficiency and low cost are achievable despite the use of sophisticated hardware and software in a nuclear environment

  3. Eddy Current Rail Inspection Using AC Bridge Techniques

    OpenAIRE

    Liu, Ze; Koffman, Andrew D; Waltrip, Bryan C; Wang, Yicheng

    2013-01-01

    AC bridge techniques commonly used for precision impedance measurements have been adapted to develop an eddy current sensor for rail defect detection. By using two detection coils instead of just one as in a conventional sensor, we can balance out the large baseline signals corresponding to a normal rail. We have significantly enhanced the detection sensitivity of the eddy current method by detecting and demodulating the differential signal of the two coils induced by rail defects, using a di...

  4. Phased arrays techniques and split spectrum processing for inspection of thick titanium casting components

    International Nuclear Information System (INIS)

    In aircraft structures, titanium parts and engine members are critical structural components, and their inspection crucial. However, these structures are very difficult to inspect ultrasonically because of their large grain structure that increases noise drastically. In this work, phased array inspection setups were developed to detected small defects such as simulated inclusions and porosity contained in thick titanium casting blocks, which are frequently used in the aerospace industry. A Cut Spectrum Processing (CSP)-based algorithm was then implemented on the acquired data by employing a set of parallel bandpass filters with different center frequencies. This process led in substantial improvement of the signal to noise ratio and thus, of detectability

  5. Improvement of testing techniques for inspecting steam turbine rotor in power plant

    International Nuclear Information System (INIS)

    Steam turbine rotor is important to the Utility industry, it degrades over time due to fatigue and corrosion under high temperature and high pressure environment. Periodic inspection is required in the wake of plant annual overhaul to ensure the integrity of turbine rotor. Non-Destructive Testing of turbine rotor is usually performed using magnetic particle testing with wet fluorescent magnetic particle. However, it is very difficult to ensure the reliability of inspection due to the limitation of using one NDT method only. The crack-susceptible areas, such as turbine blade, and blade root have high incidence of stress corrosion cracking, The blade root section is difficult to locate cracks because of the complex geometry which may cause inadequate magnetic field and poor accessibility. Improved inspection practices was developed by our Department, together with remaining life analysis, in maintaining the high availability of steam turbine rotor. The newly-developed inspection system based on the practical study of magnetic field strength distribution, quality of magnetic particle bath and a combination of different NDT methods with Eddy Current Testing using absolute pen-type coil and Visual Testing using reflective mirror to examine the key areas concerned are described. TPC' experience with the well-trained technicians together with the adequate inspection procedure in detecting blade-root flaws are also discussed in the paper. Many of these inspection improvement have been applied in the fields for several times and the inspection reliability has been enhanced substantially. Results are quite encouraging and satisfactory.

  6. Development of an Ultrasonic Inspection Technique for LP Turbine Rotor Disc

    International Nuclear Information System (INIS)

    Turbine rotor disc consists of disc, bore, keyway, hub, and rim in which the typical defects are located. And these part of disc has very complicated geometry, therefore proper transducer selection, wedge design, fabrication, classification and evaluation of the signal identification are required. In this research, test block with the artificial flaws at keyway and boresurface parts have been used in order to establish the ultrasonic inspection technique for flaw detectability on disc. The analysis of the signals from the test blocks was performed. The wedges were designed according to the curvature from the discs. All the ultrasonic signals were collected and identified for evaluation. The ultrasonic inspection technique for the flaw-detection was established from this research. And it is proved that the result of this research can be applicable in the field inspection

  7. Remote Inspection Techniques for Reactor Internals of Liquid Metal Reactor by using Ultrasonic Waveguide Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Kim, Seok Hun; Lee, Jae Han

    2006-02-15

    The primary components such as a reactor core, heat exchangers, pumps and internal structures of a liquid metal reactor (LMR) are submerged in hot sodium of reactor vessel. The division 3 of ASME code section XI specifies the visual inspection and continuous monitoring as major in-service inspection (ISI) methods of reactor internal structures. Reactor core and internal structures of LMR can not be visually examined due to an opaque liquid sodium. The under-sodium viewing and remote inspection techniques by using an ultrasonic wave should be applied for the in-service inspection of reactor internals. The remote inspection techniques using ultrasonic wave have been developed and applied for the visualization and ISI of reactor internals. The under sodium viewing technique has a limitation for the application of LMR due to the high temperature and irradiation environment. In this study, an ultrasonic waveguide sensor with a strip plate has been developed for an application to the under-sodium viewing and remote inspection. The Lamb wave propagation of a waveguide sensor has been analyzed and the zero-order antisymmetric A{sub 0} plate wave was selected as the application mode of the sensor. The A{sub 0} plate wave can be propagated in the dispersive low frequency range by using a liquid wedge clamped to the waveguide. A new technique is presented which is capable of steering the radiation beam angle of a waveguide sensor without a mechanical movement of the sensor assembly. The steering function of the ultrasonic radiation beam can be achieved by a frequency tuning method of the excitation pulse in the dispersive range of the A{sub 0} mode. The technique provides an opportunity to overcome the scanning limitation of a waveguide sensor. The beam steering function has been evaluated by an experimental verification. The ultrasonic C-scanning experiments are performed in water and the feasibility of the ultrasonic waveguide sensor has been verified. The various remote

  8. Conceptual study of spectral blank out technique on inspecting of some surrogated nuclear warheads

    International Nuclear Information System (INIS)

    The authors built up a nuclear warhead verification system based on an Intranet platform. The hardware of the system consists of an Intranet server, two personnel computers and a portable high purity germanium gamma-ray spectrometer. The software, Blanking-out, is made of two modules designed for the inspecting and inspected parties respectively. Both modules are interactive and communicate through the Intranet. When the system operates, any sensitive information carried by the high resolution gamma-ray spectrum collected by the detector will be meddled by the inspected module before the package of spectral data is sent to the inspecting module to prevent a disclosure of sensitive information. After receiving the spectral data, the inspecting module will display on the screen of the inspecting PC terminal the verification results in a form of blank-out spectrum (spectral blanking-out form) or a form of a piece of phrase (phrase form). The guideline to the spectral blanking-out is that: for those ranges of energy obligated to be inspected, the inspected module should ensure that the inspecting module can display truly their objective spectrum; and for the other ranges of energy, the inspected module can blank out certain parts of the spectra based on the knowledge of sensitive information. Phrase form is rather straightforward, answering the question whether the inspected warhead is a 'uranium-type', 'plutonium-type' or 'nonnuclear type'. The authors conducted a demonstration on some surrogates for nuclear warheads to see whether the nuclear warhead verification system possesses the capability of identifying the type of a warhead and blanking-out sensitive spectral information. The demonstration was carried out successfully. Phrase form is especially recommendable due to its stronger capability to prevent sensitive information from disclosure and its higher verification credibility. The demonstration also disclosed some deficiencies of the system, such as too much

  9. Reliable NDT data risk based inspection for offshore structures

    Energy Technology Data Exchange (ETDEWEB)

    Rouhan, A. [Bureau Veritas, Marine Div., Research Dept., Courbevoie (France)

    2002-07-01

    The monitoring of existing structures is more and more based on probabilistic approaches suck as risk based inspection (RBI). In order to minimise risks and costs in monitoring, reliable inspection data are of great importance, all the more inspection, maintenance and repair (IMR) campaigns are carried out at a low frequency. This is the case for offshore structures, with expensive non-destructive underwater inspections. This kind of harsh environment leads to lower in-situ performances than those obtained in laboratory. PoD data are often used in current RBI approaches. However, false alarms are not considered in spite of some results of the ICON project (InterCalibration of Offshore NDT), showing a significant number of false indications. In this paper, some data on underwater inspections on tubular nodes are presented. It is shown how ROC curves, Pod and PFI data where obtained within the ICON project. From a structural point of view, this paper then underlines the role of false alarms in a RBI process, using a cost function and both the probability of detection and the probability of false alarm. The basic policy ''repair when crack is detected'' and ''do nothing when no crack is detected'' is shown to be not optimal, underlining the necessity to use false alarms. (orig.)

  10. Development of ultrasonic inspection technique for crack detection in retaining rings

    International Nuclear Information System (INIS)

    The majority of retaining rings which are currently in service, are composed of a material which is susceptible to stress corrosion when exposed to moisture. Due to the inherent stress levels in the shrunk-on areas, they are particularly susceptible to stress corrosion attack. Therefore, retaining rings require non-destructive examination to avert catastrophic failure. Guidelines for retaining ring inspection issued by EPRI recommend ultrasonic manual and automated methods of inspection for rings in place. Application of the conventional manual method, using S-waves is difficult, and yields unreliable results. Due to the unreliability factor, utilities have been forced to depend upon surface examination methods, such as visual and penetrant techniques. In most instances, a surface exam will necessitate the costly and potentially damaging removal of the rings from the rotor to provide full access to areas of interest. Due to the various complexities of conventional ultrasonic retaining ring inspections, it is essential that the front end ultrasonics (i.e., transducers and techniques) be optimized to produce the best possible examination. For this reason, AMDATA has developed custom transducers and techniques to enhance automated detection capability of flaws in the various suspect areas of retaining rings. When the optimized techniques are applied to generate the best possible raw data, the Intraspect /98 trademark is then used to reliably apply technique, acquire the data and perform post processing evaluations. One of the most promising ultrasonic techniques for retaining ring inspection is creeping waves. This paper investigates the use of creeping waves for retaining ring inspection

  11. Eddy Current Rail Inspection Using AC Bridge Techniques.

    Science.gov (United States)

    Liu, Ze; Koffman, Andrew D; Waltrip, Bryan C; Wang, Yicheng

    2013-01-01

    AC bridge techniques commonly used for precision impedance measurements have been adapted to develop an eddy current sensor for rail defect detection. By using two detection coils instead of just one as in a conventional sensor, we can balance out the large baseline signals corresponding to a normal rail. We have significantly enhanced the detection sensitivity of the eddy current method by detecting and demodulating the differential signal of the two coils induced by rail defects, using a digital lock-in amplifier algorithm. We have also explored compensating for the lift-off effect of the eddy current sensor due to vibrations by using the summing signal of the detection coils to measure the lift-off distance. The dominant component of the summing signal is a constant resulting from direct coupling from the excitation coil, which can be experimentally determined. The remainder of the summing signal, which decreases as the lift-off distance increases, is induced by the secondary eddy current. This dependence on the lift-off distance is used to calibrate the differential signal, allowing for a more accurate characterization of the defects. Simulated experiments on a sample rail have been performed using a computer controlled X-Y moving table with the X-axis mimicking the train's motion and the Y-axis mimicking the train's vibrational bumping. Experimental results demonstrate the effectiveness of the new detection method. PMID:26401427

  12. Monte-Carlo Simulations of Radiation-Induced Activation in a Fast-Neutron and Gamma- Based Cargo Inspection System

    OpenAIRE

    Bromberger, B.; Bar, D.; Brandis, M.; Dangendorf, V.; Goldberg, M B; Kaufmann, F.; Mor, I.; Nolte, R.; SCHMIEDEL M.; Tittelmeier, K.; Vartsky, D.; H. Wershofen

    2012-01-01

    An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron and ga...

  13. Intercomparison of techniques for inspection and diagnostics of heavy water reactor pressure tubes. Additional information

    International Nuclear Information System (INIS)

    The reports from Argentina, Canada, India, Korea and Romania are presented concerning the projects carried out under the Coordinated Research Program (CRP) I3.30.10 of the International Agency for Atomic Energy - Vienna related to 'Intercomparison of Techniques for Pressure Tube Inspection and Diagnostics'

  14. The in-service inspection of coated steel welds using Eddy-Current Techniques

    International Nuclear Information System (INIS)

    Traditionally surface crack detection in coated Ferritic Steel Welds with Eddy-Current Techniques has been difficult due to the change in material properties in the Heat Affected Zone. These typically produce signals larger than crack signals. Sophisticated probe design and construction, combined with modern electronic equipment, have largely overcome the traditional problems and now enable the advantages of Eddy-Current Techniques to be applied to In-Service Inspection of Coated Ferritic Steel Structures in the as-welded conditions. Specifically, the advantage of the technique is that under quantifiable conditions an inspection may now be carried out through corrosion protection systems. It is the intention of this paper to review the current information available, establish the limiting parameters of the technique and detail the practical experiments conducted to determine the extent of the limiting parameters. The results of these experiments are detailed. Having determined the limiting factors, outline testing procedures have been established together with relative sensitivity settings.

  15. Risk-based inspection in the United States

    International Nuclear Information System (INIS)

    Risk-based in-service inspection (RB ISI) effectively concentrates limited and costly inspection resources on systems and locations most relevant to plant safety. The thought process used in the selection of NDE methods and procedures in a RB ISI program is expected to change toward integrating NDE into integrity management, with a concentration on understanding failure mechanisms. Identifying which damage mechanisms may be operative in specific locations and applying appropriate NDE methods to detect the presence of these damage mechanisms is fundamental to success. An overview of the RB ISI process for application to nuclear power plant piping is given with particular emphasis on the role of NDE and NDE reliability. A probabilistic model is outlined that provides a tool for evaluating various inspection strategies and their contribution to risk reduction

  16. Generic Reliability-Based Inspection Planning for Fatigue Sensitive Details

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Straub, Daniel; Faber, Michael Havbro

    fatigue sensitive details in fixed offshore steel jacket platforms and FPSO ship structures. Inspection and maintenance activities are planned such that code based requirements to the safety of personnel and environment for the considered structure are fulfilled and at the same time such that the overall...

  17. Inspection of the Grand Gulf Nuclear Station reactor coolant pump shaft using the cylindrically guided wave technique

    International Nuclear Information System (INIS)

    This paper describes the inspection of the Grand Gulf Nuclear Station reactor coolant pump shaft using the cylindrically guided wave technique. The topics of the paper include a description of the pump shaft problem, metallurgical testing results, nondestructive examination (NDE) requirements, NDE work conducted, conventional inspection technology, cylindrically guided wave technique (CGWT), and the results of CGWT inspection on boiling water reactor pump shaft. The paper consists of overheads from the presentation

  18. Multisensor-based robotic systems for inspection and manipulation tasks

    International Nuclear Information System (INIS)

    The advanced technology division of the US Department of Energy is sponsoring research at four universities (Florida, Michigan, Tennessee, and Texas) and the Oak Ridge National Laboratory (ORNL) directed toward the development of advanced robotic systems for use in nuclear environments. The primary motivation for using robotic technology in such hazardous environments is to reduce exposure and costs associated with performing tasks such as surveillance, maintenance, and repair. The main focus of research at the University of Tennessee has been to contribute to the development of autonomous inspection and manipulation systems, which utilize a wide array of sensory inputs in controlling the actions of a stationary robot. This involves several important research issues, including selection of sensor modalities, processing and analysis of data acquired by individual sensors, integration of sensory information, control of the robotic arm and end effectors, and efficient computational architectures for implementing various algorithms. Experimental research effort is directed toward design and evaluation of new methodologies using a laboratory-based robotic test bed. A unique feature of this test bed is a multisensor module that is useful in the characterization of the robots work space. In this paper, the authors describe the development of a robotic vision system for automatic spill detection, localization, and cleanup verification and the development of efficient techniques for analyzing range images using a parallel computer. The simulated spill cleanup scenario allows demonstration of the applicability of robotic systems to problems encountered in nuclear environments

  19. Pool inspection techniques for surveillance and further development of high burnup fuel assemblies

    International Nuclear Information System (INIS)

    The pool inspection techniques which have been used in fuel assembly surveillance programs for many years are suitable for high burnup fuel assemblies too. The techniques have been adapted to the requirements of new fuel assembly concepts with higher burnup potential. For high burnup, the emphasis within the scope of examination techniques available has shifted towards a characterization of the corrosion behaviour and surveillance of the geometrical dimensions of the fuel assemblies. In order to accomplish these tasks complementary techniques will have to be developed. (orig.)

  20. Interferometer -based Technology for Optical Nanoscale Inspection

    Directory of Open Access Journals (Sweden)

    Ryabko M.

    2014-02-01

    Full Text Available We demonstrate the interferometer-based approach for nanoscale grating Critical Dimension (CD measurements and prove the possibility to achieve no worse than 10 nm accuracy of measurements for 100 nm pitch gratings. The approach is based on phase shift measurement of light fields specularly reflected from periodical pattern and adjacent substrate with subsequent comparison between experimental and simulation results. RCWA algorithm is used to fit the measured results and extract the CD value. It is shown that accuracy of CD value measurement depends rather on the grating’s CD/pitch ratio than its CD value

  1. Long range guided wave inspection of a small-bone tube with the magnetostrictive transducer technique

    International Nuclear Information System (INIS)

    There are several incidents from the leakage of the pipes which are in the category of a safety class as well as a non-safety class in nuclear power plants. However, in many cases, because of their geometrical complexity and inaccessibility, it is difficult to inspect them by the conventional ultrasonic method. A long-range guided ultrasonic inspection, thus, is an option to inspect them during an outage period. The magnetostrictive transducer technique has several advantages for practical applications, for such as a 100-percent volumetric coverage of a long segment of a structure, the inspection time and its cost effective, with a relatively simple and easy transducer structure. This study investigated the applicability of a long-rang guided ultrasonic method for the detection of artificial notches even in the presence of various foreign objects. Both the torsional (T(0,1) mode) and the longitudinal (L(0,1) mode) guided ultrasonic waves were effective for the long-range inspection of the tubes. It showed that it had a good detectability for the notch in the tubes, even though several obstacles are attached in front of the notch.

  2. Development of Under-Sodium Inspection Technique Using Ultrasonic Waveguide Sensor

    International Nuclear Information System (INIS)

    The under-sodium inspection technique using ultrasonic waveguide sensor has been developed for the in-service inspection of a reactor core and in-vessel structures in the sodium-cooled fast reactor. The 10 m long prototype ultrasonic waveguide sensor modules have been designed and manufactured for the applications of under-sodium viewing and ranging. The real-scale test facility with a 13 m H-beam structure was constructed for the feasibility tests of the prototype ultrasonic waveguide sensor modules. The inspection program has been developed for the under-sodium inspection using the prototype ultrasonic waveguide sensor modules. The performance of the ultrasonic waveguide sensor modules has been successfully demonstrated in water. A novel under-sodium ultrasonic waveguide sensor with beryllium and nickel coating layers is suggested for the enhancement of the radiation and wetting performance of ultrasonic waveguide sensor in sodium. The sodium test facility with a glove box system and a sodium tank has been designed and fabricated to carry out the performance test of under-sodium ultrasonic waveguide sensor in sodium environment condition. The sensitivity and C-scan imaging tests have been carried out in sodium for evaluating performance of the under-sodium ultrasonic waveguide sensor. (author)

  3. Application of neutron radiography technique in the explosives and pyrotechnical components inspection

    International Nuclear Information System (INIS)

    The IPEN-CNEN/SP and the IAE/CTA performed a study concerning the quality control of pyrotechnic devices and explosives employed in rocket and satellite, by means of the neutron radiography technique. The radiographs were performed in a facility installed at the radial beam hole 08 of the IEA-R1 Nuclear Research Reactor of the IPEN-CNEN/SP. The results were evaluated by visual inspection as well as by digital image processing and demonstrated the techniques viability for this purpose and an improvement of the quality results due to this processing. (author). 8 refs, 5 figs, 1 tab

  4. Realtime Vision-Based Surface Defect Inspection of Steel Balls

    Institute of Scientific and Technical Information of China (English)

    Wang Zhong; Xing Qian; Fu Luhua; Sun Hong

    2015-01-01

    In the proposed system for online inspection of steel balls, a diffuse illumination is developed to enhance defect appearances and produce high quality images. To fully view the entire sphere, a novel unfolding method is put forward based on geometrical analysis, which only requires one-dimensional movement of the balls and a pair of cam-eras to capture images from different directions. Moreover, a realtime inspection algorithm is customized to improve both accuracy and efficiency. The precision and recall of the sample set were 87.7% and 98%, respectively. The aver-age time cost on image processing and analysis for a steel ballwas 47 ms, and the total time cost was less than 200 ms plus the cost of image acquisition and balls’ movement. The system can sort 18 000 balls per hour with a spatial reso-lution higher than 0.01 mm.

  5. Machine vision inspection of rice seed based on Hough transform

    Institute of Scientific and Technical Information of China (English)

    成芳; 应义斌

    2004-01-01

    A machine vision system was developed to inspect the quality of rice seeds. Five varieties of Jinyou402,Shanyou 10, Zhongyou207, Jiayou and Ilyou were evaluated. The images of both sides of rice seed with black background and white background were acquired with the image processing system for identifying external features of rice seeds. Five image sets consisting of 600 original images each were obtained. Then a digital image processing algorithm based on Hough transform was developed to inspect the rice seeds with incompletely closed glumes. The algorithm was implemented with all image sets using a Matlab 6.5 procedure. The results showed that the algorithm achieved an average accuracy of 96% for normal seeds, 92% for seeds with fine fissure and 87% for seeds with incompletely closed glumes. The algorithm was proved to be applicable to different seed varieties and insensitive to the color of the background.

  6. Application of non-destructive liner thickness measurement technique for manufacturing and inspection process of zirconium lined cladding tube

    International Nuclear Information System (INIS)

    Recently, in order to meet the difference of electric power demand owing to electric power situation, large scale load following operation has become necessary. Therefore, the development of the cladding tubes which withstand power variation has been carried out, as the result, zirconium-lined zircaloy 2 cladding tubes have been developed. In order to reduce the sensitivity to stress corrosion cracking, these zirconium-lined cladding tubes require uniform liner thickness over the whole surface and whole length. Kobe Steel Ltd. developed the nondestructive liner thickness measuring technique based on ultrasonic flaw detection technique and eddy current flaw detection technique. These equipments were applied to the manufacturing and inspection processes of the zirconium-lined cladding tubes, and have demonstrated superiority in the control and assurance of the liner thickness of products. Zirconium-lined cladding tubes, the development of the measuring technique for guaranteeing the uniform liner thickness and the liner thickness control in the manufacturing and inspection processes are described. (Kako, I.)

  7. Computer vision based end cap weld quality inspection system

    International Nuclear Information System (INIS)

    This paper describes a weld quality inspection system that has been developed for QA(F), NFC to evaluate the PHWR end cap welds. The system consists of a trinocular microscope with a video camera connected through a video reduction lens, PCI video frame grabber and PC based acquisition and analysis software. The software developed in the VC++ under windows operating system calculates the non-fusion percentage for the weld specimens in two different modes of computing i.e. Indian welding inspection method and Canadian welding inspection method. The software uses image processing and analysis algorithms to automatically identify the lack of fusion lines as per user supplied parameters for a specific set-up of the system. The lack of fusion lines and the region of interest that was used for computation are marked on the image and can be saved for future reference. GUI for user interaction to delete or add non-fusion lines is also provided. A report generation module has been integrated with the analysis software as per user requirements. Reports are generated for the end cap welding performance including machine set up, machine qualification and operator qualification information. (author)

  8. Safety Inspection System Based on the Internet of Things

    Directory of Open Access Journals (Sweden)

    Dong-Tao Hu

    2013-01-01

    Full Text Available The Safety inspection system uses the Internet of things technology to identify the location of mobile terminal automatically and bring up the correspondent safety inspection table through the equipments of Hand-hold Terminal and specific location wireless router. Inspection information including the inspection results, photos or video can be transport to general platform for storing and processing through the wireless network immediately. The process of safety inspection and hidden trouble rectification have been formed a closed-loop management system which start from the draft and inquiry of the inspection table to the implementation of safety inspection, the feedback of results, the instruction about of rectify hidden trouble, the inspection and acceptance of results. At last, it also solves the problem of timely record the dynamic checking information; make the operability of safety inspection system greatly enhanced.

  9. From PISC to risk informed inspection

    International Nuclear Information System (INIS)

    In this paper the correlation between inspection effectiveness, inspection qualification and risk informed inspection will be treated in view of harmonisation of inspection of nuclear plant components. Through the different phases of the PISC programme the necessity has been demonstrated to show the effectiveness of the inspection through a formal process of qualification in order to ensure that a certain level of effectiveness has been reached. Inspection qualification is indeed the way to quantify the capability level of inspection techniques used. The targets to be met by the inspection is information which should be obtained from risk based analyses. (author)

  10. Alternative instrumented inspection technique to the hydrostatic testing requirements of the ASME

    International Nuclear Information System (INIS)

    The Code of Federal Regulations (CFR) Title 10 requires that testing or inspection of a specified nuclear plant system or component is to the maximum extent practical in accordance with generally recognized codes and standards. Piping, pumps, and valves that are classified as ASME code class 1, 2, and 3 are required to be designed to enable the performance of in-service inspection (ISI) and testing as set forth in Section XI of the Boiler and Pressure Vessel Code. The application of instrumented inspection techniques (IIT) has been demonstrated as a suitable alternative to ASME Section XI requirements for pressure testing, system leakage, functional, hydrostatic, and pneumatic tests of class 1, 2, and 3 systems and components. The IIT method requires a preliminary systems analysis and special equipment in applying the best operational, technical, and economical methods to locate external and intersystem boundary leaks. The IIT identifies system leakages and in many instances the specific leak rate through individual boundary valves. It is in most cases nonintrusive on plant operations, more cost- and time-effective and, in keeping with ALARA considerations, results in radiation doses considerably lower than those taken during conventional testing

  11. Evaluation of computer-based ultrasonic inservice inspection systems

    International Nuclear Information System (INIS)

    This report presents the principles, practices, terminology, and technology of computer-based ultrasonic testing for inservice inspection (UT/ISI) of nuclear power plants, with extensive use of drawings, diagrams, and LTT images. The presentation is technical but assumes limited specific knowledge of ultrasonics or computers. The report is divided into 9 sections covering conventional LTT, computer-based LTT, and evaluation methodology. Conventional LTT topics include coordinate axes, scanning, instrument operation, RF and video signals, and A-, B-, and C-scans. Computer-based topics include sampling, digitization, signal analysis, image presentation, SAFI, ultrasonic holography, transducer arrays, and data interpretation. An evaluation methodology for computer-based LTT/ISI systems is presented, including questions, detailed procedures, and test block designs. Brief evaluations of several computer-based LTT/ISI systems are given; supplementary volumes will provide detailed evaluations of selected systems

  12. Evaluation of computer-based ultrasonic inservice inspection systems

    Energy Technology Data Exchange (ETDEWEB)

    Harris, R.V. Jr.; Angel, L.J.; Doctor, S.R.; Park, W.R.; Schuster, G.J.; Taylor, T.T. [Pacific Northwest Lab., Richland, WA (United States)

    1994-03-01

    This report presents the principles, practices, terminology, and technology of computer-based ultrasonic testing for inservice inspection (UT/ISI) of nuclear power plants, with extensive use of drawings, diagrams, and LTT images. The presentation is technical but assumes limited specific knowledge of ultrasonics or computers. The report is divided into 9 sections covering conventional LTT, computer-based LTT, and evaluation methodology. Conventional LTT topics include coordinate axes, scanning, instrument operation, RF and video signals, and A-, B-, and C-scans. Computer-based topics include sampling, digitization, signal analysis, image presentation, SAFI, ultrasonic holography, transducer arrays, and data interpretation. An evaluation methodology for computer-based LTT/ISI systems is presented, including questions, detailed procedures, and test block designs. Brief evaluations of several computer-based LTT/ISI systems are given; supplementary volumes will provide detailed evaluations of selected systems.

  13. Reliability-based inspection of prestressed concrete containment structures

    International Nuclear Information System (INIS)

    A study was undertaken to develop a reliability-based approach to the planning of inspection programs for prestressed concrete containment structures. The main function of the prestressing system is to ensure the leak integrity of the containment by maintaining a compressive state of stress under the tensile forces which arise in a hypothesized loss of coolant accident. Prestressing force losses (due to creep and shrinkage, stress relaxation or tendon corrosion) can lead to tensile stresses under accident pressure, resulting in loss of containment leak integrity due to concrete cracking and tensile yielding of the non-prestressed reinforcement. Therefore, the evaluation of prestressing inspection programs was based on their effectiveness in maintaining an acceptable reliability level with respect to a limit state representing yeilding of non-prestressed reinforcement. An annual target reliability of 10-4 was used for this limit state. As specified in CSA-N287.7, the evaluation of prestressing systems for containment structures is based on the results of lift-off tests to determine the prestressing force. For unbonded systems the tests are carried out on a randomly selected sample from each tendon group in the structure. For bonded systems, the test is carried out on an unbonded test beam that matches the section geometry and material properties of the containment structure. It was found that flexural testing is useful in updating the probability of concrete cracking under accident pressure. For unbonded systems, the analysis indicated that the sample size recommended by the CSA Standard (4% of the tendon population) is adequate. The CSA recommendation for a five year inspection interval is conservative unless severe degradation of the prestressing system, characterized by a high prestressing loss rate (>3%) and a large coefficient of variation of the measured prestressing force (>15%), is observed

  14. Risk-based Inspection Planning Optimisation of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramirez, José Rangel; Sørensen, John Dalsgaard

    2011-01-01

    inspection strategies to ‘control’ the deterioration in facilities such as offshore wind turbines (OWT), where fatigue and corrosion are typically affecting these structures. This article considers an RBI approach applied to OWT based on the developed methodologies for oil and gas installations, but......Wind industry is substantially propelled and the future scenarios designate offshore locations as important sites for energy production. With this development, offshore wind farms represent a feasible option to accomplish the needed energy, bringing with it technical and economical challenges...

  15. Usability study of a risk based inspection software

    OpenAIRE

    Balestrand, Christian

    2011-01-01

    Usability, or the “ease of use” of a software application, is important in order to allow for a user to carry out the intended task in an efficient and effective manner. For a technical software, as the risk based inspection (RBI) software studied in this thesis, such aspects is equally important. But in order to ensure a software which is “easy to use” there must be carried out usability activities in relation to the software’s development. The goal of the thesis was to carry ...

  16. Beam steering technique of ultrasonic waveguide sensor for under-sodium inspection of sodium fast reactor

    International Nuclear Information System (INIS)

    The reactor core and internal structures of a sodium fast reactor can not be visually examined due to the opaque sodium. The under sodium inspection technique using an ultrasonic wave should be applied for the in-service inspection of the reactor internals. Immersion sensor and waveguide sensor have been utilized for the under-sodium viewing application. The immersion sensor has a precise imaging capability, but may have high temperature restrictions and an uncertain life. The waveguide sensor has the advantages of simplicity and reliability, but limits in its movement. In this study, new ultrasonic techniques are being developed to overcome the scanning limitation of a waveguide sensor. A new technique is presented which is capable of steering an ultrasonic beam of an waveguide sensor without a mechanical movement of the sensor assembly. The steering function of the ultrasonic radiation beam can be achieved by a frequency tuning method of the excitation pulse in the dispersive low frequency range of the A0 Lamb wave. (authors)

  17. Feasibility of developing risk-based rankings of pressure boundary systems for inservice inspection

    Energy Technology Data Exchange (ETDEWEB)

    Vo, T.V.; Smith, B.W.; Simonen, F.A.; Gore, B.F.

    1994-08-01

    The goals of the Evaluation and Improvement of Non-destructive Examination Reliability for the In-service Inspection of Light Water Reactors Program sponsored by the Nuclear Regulatory Commission at Pacific Northwest Laboratory (PNL) are to (1) assess current ISI techniques and requirements for all pressure boundary systems and components, (2) determine if improvements to the requirements are needed, and (3) if necessary, develop recommendations for revising the applicable ASME Codes and regulatory requirements. In evaluating approaches that could be used to provide a technical basis for improved inservice inspection plans, PNL has developed and applied a method that uses results of probabilistic risk assessment (PRA) to establish piping system ISI requirements. In the PNL program, the feasibility of generic ISI requirements is being addressed in two phases. Phase I involves identifying and prioritizing the systems most relevant to plant safety. The results of these evaluations will be later consolidated into requirements for comprehensive inservice inspection of nuclear power plant components that will be developed in Phase II. This report presents Phase I evaluations for eight selected plants and attempts to compare these PRA-based inspection priorities with current ASME Section XI requirements for Class 1, 2 and 3 systems. These results show that there are generic insights that can be extrapolated from the selected plants to specific classes of light water reactors.

  18. Feasibility of developing risk-based rankings of pressure boundary systems for inservice inspection

    International Nuclear Information System (INIS)

    The goals of the Evaluation and Improvement of Non-destructive Examination Reliability for the In-service Inspection of Light Water Reactors Program sponsored by the Nuclear Regulatory Commission at Pacific Northwest Laboratory (PNL) are to (1) assess current ISI techniques and requirements for all pressure boundary systems and components, (2) determine if improvements to the requirements are needed, and (3) if necessary, develop recommendations for revising the applicable ASME Codes and regulatory requirements. In evaluating approaches that could be used to provide a technical basis for improved inservice inspection plans, PNL has developed and applied a method that uses results of probabilistic risk assessment (PRA) to establish piping system ISI requirements. In the PNL program, the feasibility of generic ISI requirements is being addressed in two phases. Phase I involves identifying and prioritizing the systems most relevant to plant safety. The results of these evaluations will be later consolidated into requirements for comprehensive inservice inspection of nuclear power plant components that will be developed in Phase II. This report presents Phase I evaluations for eight selected plants and attempts to compare these PRA-based inspection priorities with current ASME Section XI requirements for Class 1, 2 and 3 systems. These results show that there are generic insights that can be extrapolated from the selected plants to specific classes of light water reactors

  19. Study on in-vessel ISI for JOYO. Technical survey of under sodium non-destructive inspection technique and study of application concept

    International Nuclear Information System (INIS)

    This report is concerning the in-vessel in-service inspection (ISI) technology for the experimental fast reactor JOYO. The present ISI method in JOYO is not able to confirm the integrity of the core structure directly, expecting the visual inspection for the top of core assemblies from above the rotating plug. The purpose of this examination is to progress of the ISI method, and to confirm the integrity of the core structure directly. The core support plate is an important structure and it is selected for the object of in-vessel ISI. From the viewpoint of the influence on the plant, it is regarded important the method without all sodium draining, and the remote operation from above of the shielding plug. As a result, following technology is thought promising. Under sodium inspection technique by means of ultrasonic method (it is able to apply in-vessel ISI without all sodium draining). Nondestructive inspection technique by laser based ultrasonic method (it is superior in remote operating). The local sodium discharge mechanism (it makes possible to apply laser based ultra sonic method for under sodium inspection). These technologies were investigated, examined, and the concept applied to ISI in JOYO core support plate was examined. Moreover, the problem when these were applied to in-vessel ISI in JOYO was picked up. (author)

  20. Safety Inspection System Based on the Internet of Things

    OpenAIRE

    Dong-Tao Hu; Yu-Jie Wang; Jian Chen; Ying Sun

    2013-01-01

    The Safety inspection system uses the Internet of things technology to identify the location of mobile terminal automatically and bring up the correspondent safety inspection table through the equipments of Hand-hold Terminal and specific location wireless router. Inspection information including the inspection results, photos or video can be transport to general platform for storing and processing through the wireless network immediately. The process of safety i...

  1. Ultrasonic inspection techniques for two weld closures proposed for RSSF waste storage casks

    International Nuclear Information System (INIS)

    One method being considered for interim storage of high-level radioactive waste materials is to place these materials in large sealed stainless steel canisters and subsequently store these canisters in a second sealed steel storage cask. Weld procedures are proposed as the closure or seal for these vessels. Inspection of these closures to assure initial and long-term integrity of the closure welds presents a challenge to nondestructive testing. The environment is thermally (400 to 10000F) and radioactively (105 R/hr) hot necessitating remote inspection procedures. As a result of research work, ultrasonic test techniques were developed for inspecting the final weld closure of the waste cask. Special transducers, coupling techniques and fixturing were developed and demonstrated in a mockup test facility by remotely examining a 2-in. full penetration weld closure. The examination was performed at room ambient and at a temperature of 2000F. Testing at the desired temperature of 4000F was not completed due to a loss in transducer performance at temperatures in excess of 2000F. Upon completion of the mockup test demonstration, the cask was subjected to a drop test. The ultrasonic results of the pre- and post-examination of two weld closures (the 2-in. full penetration weld and the threaded plug with seal weld) are presented. After the completion of the drop test, both weld closures were radiographed. The radiographs verified the ultrasonic examination and the presence of weld defects in the same areas. Sectioning of the cask closure welds with metallographic verification was not completed at the time of this writing. As a result of the experience gained from the Retrievable Surface Storage Facility (RSSF) storage cask program, recommendations pertaining to the nondestructive engineering development program for Spent Unreprocessed Fuel (SURF) storage casks are presented

  2. A Laser-based Ultrasonic Inspection System to Detect Micro Fatigue Cracks

    International Nuclear Information System (INIS)

    Laser-based ultrasonic techniques have been established as a viable non-contact alternative to piezoelectric transducers for generating and receiving ultrasound. Laser-based ultrasonic inspection system provides a number of advantages over the conventional generation by piezoelectric transducers, especially a non-contact generation and detection of ultrasonic waves, high spatial scanning resolution, controllable narrow-band and wide-band spectrum, absolute measurements of the moving distance, use of fiber optics, and an ability to operate on curved and rough surfaces and at hard-to-access locations like a nuclear power plant. Ochiai and Miura used the laser-based ultrasound to detect micro fatigue cracks for the inspection of a material degradation in nuclear power plants. This widely applicable laser-based ultrasonic inspection system is comparatively expensive and provides low signal-to-noise ratio to measure ultrasound by using the laser interferometer. Many studies have been carried out to improve the measuring efficiency of the laser interferometer. One of the widely used laser interferometer types to measure the ultrasound is the Confocal Fabry-Perot Interferometer(CFPI). The measurement gain of the CFPI is slightly and continually varied according to the small change of the cavity length and the fluctuations of the measuring laser beam frequency with time. If we continually adjust the voltage of a PZT which is fixed to one of the interferometer mirrors, the optimum working point of the CFPI can be fixed. Though a static stabilizer can fix the gain of the CFPI where the CW laser beam is targeted at one position, it can not be used when the CW laser beam is scanned like a scanning laser source(SLS) technique. A dynamic stabilizer can be used for the scanning ultrasonic inspection system. A robust dynamic stabilizer is needed for an application to the industrial inspection fields. Kromine showed that the SLS technique is effective to detect small fatigue cracks

  3. Use of knowledge based systems for rational reliability analysis based inspection and maintenance planning for offshore structures

    International Nuclear Information System (INIS)

    The structural integrity of fixed offshore platforms is ensured by periodic inspections. In the past, decisions made as to when, where and how to inspect have been made by engineers using rules-of-thumb and general planning heuristics. It is now hoped that more rational inspection and maintenance scheduling may be carried out by applying recently developed techniques based on structural reliability methods. However, one of the problems associated with a theoretical approach is that it is not always possible to incorporate all the constraints that are present in a practical situation. These constraints modify the decisions made for analysis data input and the interpretation of the analysis results. Knowledge based systems provide a mean of encapsulating several different forms of information and knowledge within a computer system and hence can overcome this problem. In this paper, a prototype system being developed for integrating reliability based analysis with other constraints for inspection scheduling will be described. In addition, the scheduling model and the algorithms to carry out the scheduling will be explained. Furthermore, implementation details are also given

  4. Registration of point cloud data for HDD stamped base inspection

    Science.gov (United States)

    Suh, Sungho; Cho, Hansang

    2015-09-01

    As a part of the HDD manufacturing process, HDD stamped base, an exterior container, is one of the most essential components in which various parts become assembled to compose a hard disk drive (HDD). Height errors that are caused by pressing, breaking or cracking can occur on the base, because it is designed by a stamping method. In order to detect the height errors, the inspection process is essential in the production fields. In the current industry, CMM (Coordinate Measurement Machine) is one of the representative machines that inspect certain regions on the product. The machine probes a designated point by an operator and judges the defect by comparing the height of the point to the originally designed height. However, the method takes much time to inspect each designated point resulting in a total of 17 minutes. In order to reduce the total inspection time, we propose an inspection method using 3D point cloud data acquired from a holographic sensor. To compare the height from acquired 3D point cloud data with the one from the originally designed CAD data, the exact point cloud registration is important. There are differences between 2D image registration and 3D point cloud registration, such as translation on each plane, rotation, tilt, and nonlinear transformations. The relationship between the acquired 3D point cloud data and the originally designed CAD data can be obtained by projective transformation. If the projective transformation matrix between the two is obtained, 3D point cloud data registration can be performed. In order to calculate 3D projective transformation matrix, corresponding points between 3D point cloud data and CAD data are required. To find the corresponding points, we use the height map which is projected from 3D point cloud data onto XY plane. The height map has pixel intensity from the height value of each point. If the height maps from 3D point cloud data and CAD data are matched, corresponding points can be estimated. As one of the

  5. A physics-based defects model and inspection algorithm for automatic visual inspection

    Science.gov (United States)

    Xie, Yu; Ye, Yutang; Zhang, Jing; Liu, Li; Liu, Lin

    2014-01-01

    The representation of physical characteristics is the most essential feature of mathematical models used for the detection of defects in automatic inspection systems. However, the feature of defects and formation of the defect image are not considered enough in traditional algorithms. This paper presents a mathematical model for defect inspection, denoted as the localized defects image model (LDIM), is different because it modeling the features of manual inspection, using a local defect merit function to quantify the cost that a pixel is defective. This function comprises two components: color deviation and color fluctuation. Parameters related to statistical data of the background region of images are also taken into consideration. Test results demonstrate that the model matches the definition of defects, as defined by international industrial standards IPC-A-610D and IPC-A-600G. Furthermore, the proposed approach enhances small defects to improve detection rates. Evaluation using a defects images database returned a 100% defect inspection rate with 0% false detection. Proving that this method could be practically applied in manufacture to quantify inspection standards and minimize false alarms resulting from human error.

  6. Linac based photofission inspection system employing novel detection concepts

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, John, E-mail: jstevenson@rapiscansystems.com [Rapiscan Laboratories, Inc., 520 Almanor Avenue, Sunnyvale, CA 94085 (United States); Gozani, Tsahi, E-mail: tgozani@rapiscansystems.com [Rapiscan Laboratories, Inc., 520 Almanor Avenue, Sunnyvale, CA 94085 (United States); Elsalim, Mashal; Condron, Cathie; Brown, Craig [Rapiscan Laboratories, Inc., 520 Almanor Avenue, Sunnyvale, CA 94085 (United States)

    2011-10-01

    Rapiscan Systems is developing a LINAC based cargo inspection system for detection of special nuclear material (SNM) in cargo containers. The system, called Photofission Based Alarm Resolution (PBAR) is being developed under a DHD/DNDO Advanced Technology Demonstration (ATD) program. The PBAR system is based on the Rapiscan Eagle P9000 X-ray system, which is a portal system with a commercial 9 MeV LINAC X-ray source. For the purposes of the DNDO ATD program, a conveyor system was installed in the portal to allow scanning and precise positioning of 20 ft ISO cargo containers. The system uses a two step inspection process. In the first step, the basic scan, the container is quickly and completely inspected using two independent radiography arrays: the conventional primary array with high spatial resolution and a lower resolution spectroscopic array employing the novel Z-Spec method. The primary array uses cadmium tungstate (CdWO{sub 4}) detectors with conventional current mode readouts using photodiodes. The Z-Spec array uses small plastic scintillators capable of performing very fast (up to 10{sup 8} cps) gamma-ray spectroscopy. The two radiography arrays are used to locate high-Z objects in the image such as lead, tungsten, uranium, which could be potential shielding materials as well as SNM itself. In the current system, the Z-Spec works by measuring the energy spectrum of transmitted X-rays. For high-Z materials the higher end of the energy spectrum is more attenuated than for low-Z materials and thus has a lower mean energy and a narrower width than low- and medium-Z materials. The second step in the inspection process is the direct scan or alarm clearing scan. In this step, areas of the container image, which were identified as high Z, are re-inspected. This is done by precisely repositioning the container to the location of the high-Z object and performing a stationary irradiation of the area with X-ray beam. Since there are a large number of photons in the 9

  7. Linac based photofission inspection system employing novel detection concepts

    Science.gov (United States)

    Stevenson, John; Gozani, Tsahi; Elsalim, Mashal; Condron, Cathie; Brown, Craig

    2011-10-01

    Rapiscan Systems is developing a LINAC based cargo inspection system for detection of special nuclear material (SNM) in cargo containers. The system, called Photofission Based Alarm Resolution (PBAR) is being developed under a DHD/DNDO Advanced Technology Demonstration (ATD) program. The PBAR system is based on the Rapiscan Eagle P9000 X-ray system, which is a portal system with a commercial 9 MeV LINAC X-ray source. For the purposes of the DNDO ATD program, a conveyor system was installed in the portal to allow scanning and precise positioning of 20 ft ISO cargo containers. The system uses a two step inspection process. In the first step, the basic scan, the container is quickly and completely inspected using two independent radiography arrays: the conventional primary array with high spatial resolution and a lower resolution spectroscopic array employing the novel Z-Spec method. The primary array uses cadmium tungstate (CdWO 4) detectors with conventional current mode readouts using photodiodes. The Z-Spec array uses small plastic scintillators capable of performing very fast (up to 10 8 cps) gamma-ray spectroscopy. The two radiography arrays are used to locate high-Z objects in the image such as lead, tungsten, uranium, which could be potential shielding materials as well as SNM itself. In the current system, the Z-Spec works by measuring the energy spectrum of transmitted X-rays. For high-Z materials the higher end of the energy spectrum is more attenuated than for low-Z materials and thus has a lower mean energy and a narrower width than low- and medium-Z materials. The second step in the inspection process is the direct scan or alarm clearing scan. In this step, areas of the container image, which were identified as high Z, are re-inspected. This is done by precisely repositioning the container to the location of the high-Z object and performing a stationary irradiation of the area with X-ray beam. Since there are a large number of photons in the 9 MV

  8. Linac based photofission inspection system employing novel detection concepts

    International Nuclear Information System (INIS)

    Rapiscan Systems is developing a LINAC based cargo inspection system for detection of special nuclear material (SNM) in cargo containers. The system, called Photofission Based Alarm Resolution (PBAR) is being developed under a DHD/DNDO Advanced Technology Demonstration (ATD) program. The PBAR system is based on the Rapiscan Eagle P9000 X-ray system, which is a portal system with a commercial 9 MeV LINAC X-ray source. For the purposes of the DNDO ATD program, a conveyor system was installed in the portal to allow scanning and precise positioning of 20 ft ISO cargo containers. The system uses a two step inspection process. In the first step, the basic scan, the container is quickly and completely inspected using two independent radiography arrays: the conventional primary array with high spatial resolution and a lower resolution spectroscopic array employing the novel Z-Spec method. The primary array uses cadmium tungstate (CdWO4) detectors with conventional current mode readouts using photodiodes. The Z-Spec array uses small plastic scintillators capable of performing very fast (up to 108 cps) gamma-ray spectroscopy. The two radiography arrays are used to locate high-Z objects in the image such as lead, tungsten, uranium, which could be potential shielding materials as well as SNM itself. In the current system, the Z-Spec works by measuring the energy spectrum of transmitted X-rays. For high-Z materials the higher end of the energy spectrum is more attenuated than for low-Z materials and thus has a lower mean energy and a narrower width than low- and medium-Z materials. The second step in the inspection process is the direct scan or alarm clearing scan. In this step, areas of the container image, which were identified as high Z, are re-inspected. This is done by precisely repositioning the container to the location of the high-Z object and performing a stationary irradiation of the area with X-ray beam. Since there are a large number of photons in the 9 MV

  9. Integrating design and production planning with knowledge-based inspection planning system

    International Nuclear Information System (INIS)

    In this paper an intelligent environment to integrate design and inspection earlier to the design stage. A hybrid knowledge-based approach integrating computer-aided design (CAD) and computer-aided inspection planning (CAIP) was developed, thereafter called computer-aided design and inspection planning (CADIP). CADIP was adopted for automated dimensional inspection planning. Critical functional features were screened based on certain attributes for part features for inspection planning application. Testing the model resulted in minimizing the number of probing vectors associated with the most important features in the inspected prismatic part, significant reduction in inspection costs and release of human labor. In totality, this tends to increase customer satisfaction as a final goal of the developed system. (author)

  10. New approach for risk based inspection of H2S based Process Plants

    International Nuclear Information System (INIS)

    Highlights: • Study looks into improving the consequence evaluation in risk based inspection. • Ways to revise the quantity factors used in qualitative approach. • New approach based on computational fluid dynamics along with probit mathematics. • Demonstrated this methodology along with a suitable case study for the said issue. - Abstract: Recent trend in risk informed and risk based approaches in life management issues have certainly put the focus on developing estimation methods for real risk. Idea of employing risk as an optimising measure for in-service inspection, termed as risk based inspection, was accepted in principle from late 80s. While applying risk based inspection, consequence of failure from each component needs to be assessed. Consequence evaluation in a Process Plant is a crucial task. It may be noted that, in general, the number of components to be considered for life management is very large and hence the consequence evaluation resulting from their failures (individually) is a laborious task. Screening of critical components is usually carried out using simplified qualitative approach, which primarily uses influence factors for categorisation. This necessitates logical formulation of influence factors and their ranges with a suitable technical basis for acceptance from regulators. This paper describes application of risk based inspection for H2S based Process Plant along with the approach devised for handling the influence factor related to the quantity of H2S released

  11. New techniques provide low-cost X-ray inspection of highly attenuating materials

    International Nuclear Information System (INIS)

    As a result of an arms reduction treaty between the United States and the Russian Federation, both countries will each be storing over 40,000 containers of plutonium. To help detect any deterioration of the containers and prevent leakage, the authors are designing a digital radiography and computed tomography system capable of handling this volume reliably, efficiently, and at a lower cost. The materials to be stored have very high x-ray attenuations, and, in the past, were inspected using 1- to 24-MV x-ray sources. This inspection system, however, uses a new scintillating (Lockheed) glass and an integrating CCD camera. Preliminary experiments show that this will permit the use of a 450-kV x-ray source. This low-energy system will cost much less than others designed to use a higher-energy x-ray source because it will require a less expensive source, less shielding, and less floor space. Furthermore, they can achieve a tenfold improvement in spatial resolution by using their knowledge of the point-spread function of the x-ray imaging system and a least-squares fitting technique

  12. High performance coated board inspection system based on commercial components

    CERN Document Server

    Barjaktarovic, M; Radunovic, J

    2007-01-01

    This paper presents a vision system for defect (fault) detection on a coated board developed using three industrial firewire cameras and a PC. Application for image processing and system control was realized with the LabView software package. Software for defect detection is based on a variation of the image segmentation algorithm. Standard steps in image segmentation are modified to match the characteristics of defects. Software optimization was accomplished using SIMD (Single Instruction Multiple Data) technology available in the Intel Pentium 4 processors that provided real time inspection capability. System provides benefits such as: improvement in production process, higher quality of delivered coated board and reduction of waste. This was proven during successful exploitation of the system for more than a year.

  13. Innovative Ultrasonic Techniques for Inspection and Monitoring of Large Concrete Structures

    Directory of Open Access Journals (Sweden)

    Niederleithinger E.

    2013-07-01

    Full Text Available Ultrasonic echo and transmission techniques are used in civil engineering on a regular basis. New sensors and data processing techniques have lead to many new applications in the structural investigation as well as quality control. But concrete structures in the nuclear sector have special features and parameters, which pose problems for the methods and instrumentation currently available, e.g. extreme thickness, dense reinforcement, steel liners or special materials. Several innovative ultrasonic techniques have been developed to deal with these issues at least partly in lab experiments and pilot studies. Modern imaging techniques as multi-offset SAFT have been used e. g. to map delaminations. Thick concrete walls have successfully been inspected, partly through a steel liner. Embedded ultrasonic sensors have been designed which will be used in monitoring networks of large concrete structures above and below ground. In addition, sensitive mathematical methods as coda wave interferometry have been successfully evaluated to detect subtle changes in material properties. Examples of measurements and data evaluation are presented.

  14. Innovative Ultrasonic Techniques for Inspection and Monitoring of Large Concrete Structures

    Science.gov (United States)

    Wiggenhauser, H.; Niederleithinger, E.

    2013-07-01

    Ultrasonic echo and transmission techniques are used in civil engineering on a regular basis. New sensors and data processing techniques have lead to many new applications in the structural investigation as well as quality control. But concrete structures in the nuclear sector have special features and parameters, which pose problems for the methods and instrumentation currently available, e.g. extreme thickness, dense reinforcement, steel liners or special materials. Several innovative ultrasonic techniques have been developed to deal with these issues at least partly in lab experiments and pilot studies. Modern imaging techniques as multi-offset SAFT have been used e. g. to map delaminations. Thick concrete walls have successfully been inspected, partly through a steel liner. Embedded ultrasonic sensors have been designed which will be used in monitoring networks of large concrete structures above and below ground. In addition, sensitive mathematical methods as coda wave interferometry have been successfully evaluated to detect subtle changes in material properties. Examples of measurements and data evaluation are presented.

  15. Monte-Carlo Simulations of Radiation-Induced Activation in a Fast-Neutron and Gamma- Based Cargo Inspection System

    CERN Document Server

    Bromberger, B; Brandis, M; Dangendorf, V; Goldberg, M B; Kaufmann, F; Mor, I; Nolte, R; Schmiedel, M; Tittelmeier, K; Vartsky, D; Wershofen, H

    2012-01-01

    An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron and gamma radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. T...

  16. Inspection with non destructive assay techniques of the aluminium coating of the TRIGA Mark III reactor vat

    International Nuclear Information System (INIS)

    In June 2000, the Reactor Department assigned to the Scientific Research Direction of the National Institute of Nuclear Research requested to the Non-destructive Assays Laboratory (LEND), assigned to the Materials Science Management, the inspection and measurement of thickness of the aluminium coating (liner) of the TRIGA Mark III reactor vat with non-destructive assay techniques, due to that the aluminium coating is exposed mainly to undergo slimming on its back side due to corrosion phenomena. Activity that was able to be carried out from april until august 2001. It is worth pointing out that this type of inspection with these techniques was realized by first time. The non-destructive assays (NDA) are techniques which use indirect physical methods for inspecting the sanitation of components in process or in service, for detect lack of continuity or defects which affect their quality or usefulness. The application of those do not alter the physical, chemical, mechanical or dimensional properties of the part subject of inspection. The results of the application of the ultrasound inspection techniques, industrial radiography and penetrating liquids are presented. (Author)

  17. Use of the cylindrically guided wave technique for the inspection of stud bolts, valve stems and pump shafts

    International Nuclear Information System (INIS)

    Over the last several years, nuclear power plants have expressed concern about failures of bolting, valve stems, and pump shafts. This paper reports on the development of an ultrasonic technique to inspect these components. The authors have successfully demonstrated the cylindrically guided wave technique (CGWT) on a wide range of stud bolts. The CGWT employs zero-degree longitudinal waves constrained to travel within the boundary of the cylindrically shaped components during inspection. Theoretically explained, mode conversion occurs because the ultrasonic wave is guided down the length of the component. These mode-converted signals are dependent upon the diameter of the component under inspection and the longitudinal- and shear-wave velocities of the component material. This technique has also been successfully used on valve stems in the field. The geometry of the valve stem is very similar to that of the stud bolt

  18. A study on non-contact ultrasonic technique for on-line inspection of CFRP

    International Nuclear Information System (INIS)

    The advantages of carbon fiber reinforced plastic materials (CFRP) are: they are light structure materials, they have corrosion resistance, and higher specific strength and elasticity. The recently developed 3-dimentional fiber placement system is able to produce a more complex and various shaped structures due to less limitations of a product shape according to the problem in conventional fabrication process. This fiber placement system stacks the narrow prepreg tape on the mold according to the designed sequence and thickness. Non-destructive evaluation was rquired for these composites to evaluate changes in strength caused by defects such as delamination and porosity. Additionally, the expectent quality should be satisfied for the high cost fabrication process using the fiber placement system. Therefore, an on line non-destructive evaluation system is required and real-time complement is needed when the defects are detected [1]. Defect imaging by the ultrasonic C-scan method is a useful technique for defect detection in CFRP. However, the conventional ultrasonic C-scan technique cannot be applied during the fabrication process because the test piece should be immersed into the water. Therefore, non-contact ultrasonic techniques should be applied during the fabricating process. For the development of non-contact ultrasonic techniques available in non-destructive evaluation of CFRP, a recent laser-generated ultrasonic technique and an air-coupled transducer that transmit and receive ultrasounds in the air are studied [2-3]. In this study, generating and receiving techniques of laser-generated ultrasound and the characteristics of received signals upon the internal defects of CFRO were studied for non-contact inspection

  19. Development of a laser based inspection system for surface defect detection

    OpenAIRE

    Bhuian, Mohammed Belal Hossain

    2002-01-01

    The objective of this project was to design and develop a laser based inspection system for the detection of surface defects and to assess its potentiality for high-speed online applications. The basic components of this inspection system are a laser diode module as illumination source, a random access CMOS camera as detector unit, and an XYZ translation stage. Algorithms were developed to analyze the data obtained from the scanning of different sample surfaces. The inspection system was base...

  20. Application of dual-energy x-ray techniques for automated food container inspection

    Science.gov (United States)

    Shashishekhar, N.; Veselitza, D.

    2016-02-01

    Manufacturing for plastic food containers often results in small metal particles getting into the containers during the production process. Metal detectors are usually not sensitive enough to detect these metal particles (0.5 mm or lesser), especially when the containers are stacked in large sealed shipping packages; X-ray inspection of these packages provides a viable alternative. This paper presents the results of an investigation into dual-energy X-ray techniques for automated detection of small metal particles in plastic food container packages. The sample packages consist of sealed cardboard boxes containing stacks of food containers: plastic cups for food, and Styrofoam cups for noodles. The primary goal of the investigation was to automatically identify small metal particles down to 0.5 mm diameter in size or less, randomly located within the containers. The multiple container stacks in each box make it virtually impossible to reliably detect the particles with single-energy X-ray techniques either visually or with image processing. The stacks get overlaid in the X-ray image and create many indications almost identical in contrast and size to real metal particles. Dual-energy X-ray techniques were investigated and found to result in a clear separation of the metal particles from the food container stack-ups. Automated image analysis of the resulting images provides reliable detection of the small metal particles.

  1. Risk Based Inspection Methodology and Software Applied to Atmospheric Storage Tanks

    International Nuclear Information System (INIS)

    A new risk-based inspection (RBI) methodology and software is presented in this paper. The objective of this work is to allow management of the inspections of atmospheric storage tanks in the most efficient way, while, at the same time, accident risks are minimized. The software has been built on the new risk framework architecture, a generic platform facilitating efficient and integrated development of software applications using risk models. The framework includes a library of risk models and the user interface is automatically produced on the basis of editable schemas. This risk-framework-based RBI tool has been applied in the context of RBI for above-ground atmospheric storage tanks (AST) but it has been designed with the objective of being generic enough to allow extension to the process plants in general. This RBI methodology is an evolution of an approach and mathematical models developed for Det Norske Veritas (DNV) and the American Petroleum Institute (API). The methodology assesses damage mechanism potential, degradation rates, probability of failure (PoF), consequence of failure (CoF) in terms of environmental damage and financial loss, risk and inspection intervals and techniques. The scope includes assessment of the tank floor for soil-side external corrosion and product-side internal corrosion and the tank shell courses for atmospheric corrosion and internal thinning. It also includes preliminary assessment for brittle fracture and cracking. The data are structured according to an asset hierarchy including Plant, Production Unit, Process Unit, Tag, Part and Inspection levels and the data are inherited / defaulted seamlessly from a higher hierarchy level to a lower level. The user interface includes synchronized hierarchy tree browsing, dynamic editor and grid-view editing and active reports with drill-in capability.

  2. Risk Based Inspection Methodology and Software Applied to Atmospheric Storage Tanks

    Science.gov (United States)

    Topalis, P.; Korneliussen, G.; Hermanrud, J.; Steo, Y.

    2012-05-01

    A new risk-based inspection (RBI) methodology and software is presented in this paper. The objective of this work is to allow management of the inspections of atmospheric storage tanks in the most efficient way, while, at the same time, accident risks are minimized. The software has been built on the new risk framework architecture, a generic platform facilitating efficient and integrated development of software applications using risk models. The framework includes a library of risk models and the user interface is automatically produced on the basis of editable schemas. This risk-framework-based RBI tool has been applied in the context of RBI for above-ground atmospheric storage tanks (AST) but it has been designed with the objective of being generic enough to allow extension to the process plants in general. This RBI methodology is an evolution of an approach and mathematical models developed for Det Norske Veritas (DNV) and the American Petroleum Institute (API). The methodology assesses damage mechanism potential, degradation rates, probability of failure (PoF), consequence of failure (CoF) in terms of environmental damage and financial loss, risk and inspection intervals and techniques. The scope includes assessment of the tank floor for soil-side external corrosion and product-side internal corrosion and the tank shell courses for atmospheric corrosion and internal thinning. It also includes preliminary assessment for brittle fracture and cracking. The data are structured according to an asset hierarchy including Plant, Production Unit, Process Unit, Tag, Part and Inspection levels and the data are inherited / defaulted seamlessly from a higher hierarchy level to a lower level. The user interface includes synchronized hierarchy tree browsing, dynamic editor and grid-view editing and active reports with drill-in capability.

  3. Improved plant availability by advanced condition based inspections

    International Nuclear Information System (INIS)

    An industrial plant has to operate safely, reliably and efficiently at the lowest possible cost. Plant availability plays an important role regarding economic life optimisation. Industrial installations that are under pressure and are operating at high temperatures have a limited life due to creep and fatigue. It is, therefore, of critical importance to know the location of any possible weak spots in the installation. To avoid safety risks, unplanned plant shutdown and, as a consequence, high costs for unavailability, cycling and repair, periodic inspections and strain measurements are recommended. A Speckle Image Correlation Analysis (SPICA) system enables on-stream measurement of deformation due to creep in critical areas like the heat-affected zone in welds. Plant management and operators use the strain measurements to take action when necessary and, consequently, prevent failures. In those plants that have been provided with SPICA-technology for some years plant availability has improved significantly as a result. Another important development for yielding improved availability concerns steam drums. During some 20 years, KEMA has been performing automated ultrasonic steam drum inspections from outside. The Dutch authorities accepted this methodology in this period as an alternative (rather than an addition) after several pilot projects. An advantage of this inspection methodology is the possibility to record of the inspection results and possibility of thus trending these data. The resulting reduction of through time appeared a major benefit for plant owners. Since the authorities adopted the RBI approach during the last 10 years, another advantage of the inspection methodology became apparent: complete scanning and recording of the inspection data of circumferential and longitudinal (butt and fillet) welds, inspection of nozzle welds and inner radius as well as corrosion mapping has been covering all higher risk areas in these drums. This enhanced inspection

  4. Development and validation of a real-time synthetic aperture focusing technique for ultrasonic testing (SAFT-UT) system for in-service inspection of light water reactors

    International Nuclear Information System (INIS)

    The objectives of the program is to: 1) design, fabricate, and evaluate a real-time flaw detection and characterization system based on synthetic aperture focusing technique for ultrasonic testing (SAFT-UT) for inservice inspection (ISI) of all required light water reactors (LWR) components; 2) establish calibration and field test procedures; 3) demonstrate and validate the system through actual field reactor inspections; and 4) generate an engineering data base to support code acceptance of the real-time SAFT-UT technique. The program scope is defined by the following: 1) conduct laboratory tests to provide engineering data for defining SAFT-UT system performance; 2) complete the development of a special processor to make SAFT a real-time process for ISI application; and 3) fabricate and field test a fieldable real-time SAFT-UT system on nuclear reactor piping, nozzles and pressure vessels

  5. Inspection system for welded tubular joint based on ultrasonic phased array

    Institute of Scientific and Technical Information of China (English)

    Hao Guangping; Deng Zongquan; Shan Baohua; Yu Weizhen; Li Lifang

    2010-01-01

    A manual inspection of large-diameter tubular joints is difficult. As a result a scanner with three degrees of freedom (DOFs) was developed based on the scanning principle of ultrasonic phased array. The weld tracing is realized by a 2D0F motion of scanner. The pose of ultrasonic probe is controlled by the third one. The control strategy is put forward based on a programmable multi-axis controller. Four kinds of scanning modes can be implemented simultaneously employing this ultrasonic inspection system. Experiments on reference blocks of tubular joints reveal that the automatic ultrasonic phased array inspection system has the same inspection accuracy as a manual ultrasonic inspection. This system is superior to the manual ultrasonic system in terms of reliability and repeatability. The artificial defects of weld at tubular joint can be detected accurately with the presented inspection system.

  6. Evolving the inspection techniques for determination of volumetric dimensions of ground pore in heat transfer elements

    International Nuclear Information System (INIS)

    Ground Pore is the inherent defect observed in the weld joint of Heat Transfer Element (HTE) made up of CuCrZr where the two subcomponents are joined in lap configuration. It is therefore essential to ensure that such defects would not affect the desired function of Heat Transfer Element during its operation. A study has been initiated to assess the behavior of the ground pore by simulating the heat flux and other operational parameters on the welded sample cut from HTE. Determination of the volumetric dimensions of the pores before and after application of HTE operational condition is primary essential requirement to understand the behavior of the pores. It was assessed during initial efforts that, it is almost impossible to get the volumetric dimensions of the pores with the help of conventional volumetric examination methods in partial penetration joint configuration, where the expected pore dimensions are as low as 100 microns. Therefore, advanced nondestructive examination (NDE) techniques like computer tomography (CT) having accuracy of detecting defect up to 1 micron was explored and applied for the purpose. Considering the present generation devices, thickness up to 20mm for Copper alloys can be investigated, which meets the requirement for most applications in fusion devices. Apart from this, approach of using combination of two NDE techniques like radiography and water submerged ultrasonic techniques was also explored to determine defect volume. In this paper, the approach taken to establish and validate the inspection technique to determine the volumetric dimensions of weld defect in partial penetration configuration shall be presented. (author)

  7. Seed-a distributed data base architecture for global management of steam-generator inspection data

    International Nuclear Information System (INIS)

    This paper deals with a data management system - called SEED (Steam-generator Eddy-current Expert Database) for global handling of SG (steam generator) tube inspection data in nuclear power plants. The SEED integrates all stages in SG tube inspection process and supports all data such as raw eddy current data, inspection history data, SG tube information, etc. SEED implemented under client/server computing architecture for supporting LAN/WAN based graphical user interface facilities using WWW programming tools. (author)

  8. Sandy Damage Estimates Based on FEMA IA Registrant Inspection Data

    Data.gov (United States)

    Department of Housing and Urban Development — A FEMA housing inspection for renters is used to assess personal property loss and for owners to assess damage to their home as well as personal property. This...

  9. Robotized Inspection of Vertical Structures of a Solar Power Plant Using NDT Techniques

    OpenAIRE

    Torsten Felsch; Gunnar Strauss; Carmen Perez; José M. Rego; Iñaki Maurtua; Loreto Susperregi; Jorge R. Rodríguez

    2015-01-01

    Concentrated solar power (CSP) plants are expansive facilities that require substantial inspection and maintenance. A fully automated inspection robot increases the efficiency of maintenance work, reduces operating and maintenance costs, and improves safety and work conditions for service technicians. This paper describes a climbing robot that is capable of performing inspection and maintenance on vertical surfaces of solar power plants, e.g., the tubes of the receiver in a central tower CSP ...

  10. An Image Content Description Technique for the Inspection of Specular Objects

    Directory of Open Access Journals (Sweden)

    S. Bourennane

    2008-11-01

    Full Text Available This paper proposed an image content description method within the context of specular surface inspection. Such a method is based on a preliminary research concerning the generation of specific stripe patterns for the visual enhancement of defective surface parts of cylindrical specular objects. The goal of this paper is to address the stripe pattern interpretation within a general approach. For this purpose, different pattern recognition processes, consisting not only of the combination of different image segmentation, feature retrieval, and classification, but also of feature combination and selection, will be considered. Three top-down and one bottom-up approaches are evaluated for retrieving the most appropriate feature sets in terms of highest classification rates. It will be demonstrated that following a combination and appropriate selection of these feature sets, even better rates can be reached. With only half of the initial features, an increase of more than 2% is observable.

  11. Norovirus outbreak at a wildland fire base camp ignites investigation of restaurant inspection policies.

    Science.gov (United States)

    Britton, Carla L; Guzzle, Patrick L; Hahn, Christine G; Carter, Kris K

    2014-01-01

    Norovirus outbreaks occur worldwide and have been associated with congregate settings (e.g., military and recreational camps). Investigation of a norovirus outbreak at a wildland fire base camp identified 49 (27%) illnesses among approximately 180 responders. Epidemiologic evidence implicated a restaurant as the infection source. Eight (89%) of nine wildland fire responder groups who ate at the restaurant had ill members; no groups who ate elsewhere reported ill members. An environmental health specialist restaurant inspection identified lack of managerial knowledge to protect against foodborne disease one year after the restaurant's opening; earlier inspection after opening might have led to earlier intervention. States were surveyed to determine existence of any policy or rule for food establishment inspection after opening and inspection timing. Among 18 states, five had no state rule or policy; nine had a policy in place; and four required postopening inspection by rule. Further research is needed to evaluate post-opening inspection efficacy and timing. PMID:25185322

  12. A cargo inspection system based on pulsed fast neutron analysis (PFNATM)

    International Nuclear Information System (INIS)

    A cargo inspection system based on pulsed fast neutron analysis (PFNATM) is to be used at a border crossing to detect explosives and contraband hidden in trucks and cargo containers. Neutrons are produced by the interaction of deuterons in a deuterium target mounted on a moveable scan arm. The collimated pulsed fast neutron beam is used to determine the location and composition of objects in a cargo container. The neutrons produce secondary gamma rays that are characteristic of the object's elemental composition. The cargo inspection system building consists of an accelerator room and an inspection tunnel. The accelerator room is shielded and houses the injector, accelerator and the neutron production gas target. The inspection tunnel is partially shielded. The truck or container to be inspected will be moved through the inspection tunnel by a conveyor system. The facility and radiation source terms considered in the shielding design are described. (authors)

  13. DEVELOPMENT AND TEST OF BLIMP-BASED COMPACT LIDAR POWEWR-LINE INSPECTION SYSTEM

    Directory of Open Access Journals (Sweden)

    W. W. Pan

    2015-03-01

    Full Text Available This paper introduces a compact LIDAR system designed to inspect overhead transmission line for maintenance purposes. This LIDAR system is carried by a small unmanned helium airship, which is guided by GPS and laser ranging to fly automatically along the power-line over a limited distance. The 3D coordinates of the power line, power tower and power line channel features are gathered by LIDAR. Test have been accomplished using this blimp-based compact LIDAR power-line inspection system. Its inspections of a 500kV power lines also shows the high efficient inspection, less risk to personnel and more inspections per day compared with manual inspection.

  14. Pressure vessel inspection criteria based on fitness-for-purpose assessment

    International Nuclear Information System (INIS)

    The paper on pressure vessel inspection investigates the methodology required to establish an inspection strategy consistent with fracture mechanics analysis, i.e. to define allowable flaw sizes based on location within the vessel. The methodology is demonstrated using a sample problem for a typical pressurised water reactor pressure vessel, and shows the impact of certain assumptions on the inspection strategy. The results indicate that the flaw size varies with the shape of the assumed residual stress field and the through-thickness location. Also in general, the fracture mechanics evaluation allows flaws much larger than are allowed by the inspection acceptance criteria. (UK)

  15. Remote Impedance-based Loose Bolt Inspection Using a Radio-Frequency Active Sensing Node

    International Nuclear Information System (INIS)

    This paper introduces an active sensing node using radio-frequency (RF) telemetry. This device has brought the traditional impedance-based structural health monitoring (SHM) technique to a new paradigm. The RF active sensing node consists of a miniaturized impedance measuring device (AD5933), a microcontroller (ATmega128L), and a radio frequency (RF) transmitter (XBee). A macro-fiber composite (MFC) patch interrogates a host structure by using a self-sensing technique of the miniaturized impedance measuring device. All the process including structural interrogation, data acquisition, signal processing, and damage diagnostic is being performed at the sensor location by the microcontroller. The RF transmitter is used to communicate the current status of the host structure. The feasibility of the proposed SHM strategy is verified through an experimental study inspecting loose bolts in a bolt-jointed aluminum structure

  16. Non-Intrusive Techniques of Inspections During the Pre-Launch Phase of Space Vehicle

    Science.gov (United States)

    Thirumalainambi, Rejkumar; Bardina, Jorge E.

    2005-01-01

    This paper addresses a method of non-intrusive local inspection of surface and sub-surface conditions, interfaces, laminations and seals in both space vehicle and ground operations with an integrated suite of imaging sensors during pre-launch operations. It employs an advanced Raman spectrophotometer with additional spectrophotometers and lidar mounted on a flying robot to constantly monitor the space hardware as well as inner surface of the vehicle and ground operations hardware. This paper addresses a team of micro flying robots with necessary sensors and photometers to monitor the entire space vehicle internally and externally. The micro flying robots can reach altitude with least amount of energy, where astronauts have difficulty in reaching and monitoring the materials and subsurface faults. The micro flying robot has an embedded fault detection system which acts as an advisory system and in many cases micro flying robots act as a Supervisor to fix the problems. As missions expand to a sustainable presence in the Moon, and extend for durations longer than one year in lunar outpost, the effectiveness of the instrumentation and hardware has to be revolutionized if NASA is to meet high levels of mission safety, reliability, and overall success. The micro flying robot uses contra-rotating propellers powered by an ultra-thin, ultrasonic motor with currently the world's highest power weight ratio, and is balanced in mid-air by means of the world's first stabilizing mechanism using a linear actuator. The essence of micromechatronics has been brought together in high-density mounting technology to minimize the size and weight. The robot can take suitable payloads of photometers, embedded chips for image analysis and micro pumps for sealing cracks or fixing other material problems. This paper also highlights advantages that this type of non-intrusive techniques offer over costly and monolithic traditional techniques.

  17. Vision-based surface defect inspection of metal balls

    International Nuclear Information System (INIS)

    A machine vision system developed for inspecting metal ball surface defects is presented. The proposed system is capable of inspecting the entire surface of a ball by capturing multiple gray-scale images with two progressive CCD cameras as the ball rolls on an inclined rail. The specular reflectance of the metal surface is lessened by installing a shade around the ball. Defects are detected by simply comparing each captured image with its corresponding reference image. The system built for the experiment could sort two chrome balls per second with a spatial resolution better than 0.1 mm. (technical design note)

  18. Epidemiologic and economic evaluation of risk-based meat inspection for bovine cysticercosis in Danish cattle

    DEFF Research Database (Denmark)

    Calvo Artavia, Francisco Fernando; Nielsen, Liza Rosenbaum; Alban, L.

    2013-01-01

    simulation model for analysis of tentative risk-based meat inspection systems for BC in Danish cattle with regard to system sensitivity (SSSe), specificity and potential monetary benefits compared to the current system, which has an estimated SSSe of 15%. The relevant risk factors used to construct three...... slaughterline, allowing them to do with one meat inspector less. All abattoirs would gain on the price of sold uncut beef from the masseter muscles from visually inspected cattle. Under these assumptions, using gender and grazing were preferable due to them having SSSe only slightly lower than the current...... the current meat inspection and under the investigated risk-based meat inspection systems. Therefore, improving the sensitivity of the methods used for inspection of high-risk cattle would be beneficial....

  19. In service inspection for Superphenix vessels development of ultrasonic techniques available at high temperature

    International Nuclear Information System (INIS)

    The main and safety vessels of SUPERPHENIX 1 were designed to allow in-service inspections. The remote controlled inspection device MIR was developped for this purpose. The ultrasonic examination has required the development of all new transducers fitted with severe operating conditions prevailing in intervessels interval. A list of problems to be resolved and technological solutions which were found is given. Measurements of acoustical properties on actual probes are compared with theoretical values. It appears that concordance is good and that an in-service inspection using high temperature transducers is possible with a good spatial resolution and signal to noise ratio

  20. Nondestructive techniques of repeated in-service inspections in nuclear power plants. Part 3

    International Nuclear Information System (INIS)

    The application is described of acoustic emission in testing the state and behaviour of primary circuit components during stress, in hydrostatic pressure tests during in-service inspections, and in leak testing of components under pressure. Ultrasound holography is described in visualizing defects, and the use of thermography is discussed. The systems and positioners for remote control of testing during external and internal reactor vessel inspections are listed. Equipment by major world manufacturers meet the requirements of the ASME Standard, Section IX. Other regulations and codes are listed related to periodic in-service inspections of the primary coolant circuits of nuclear installations and to nuclear safety. (B.S.)

  1. Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    Probabilistic methodologies represent an important tool to identify the suitable strategy to inspect and deal with the deterioration in structures such as offshore wind turbines (OWT). Reliability based methods such as Risk Based Inspection (RBI) planning may represent a proper methodology to...... optimize inspection and maintenance (I&M) efforts, entailing to a suitable life-cycle performance without neglecting the economical aspect. Moreover, the integration of condition monitoring information (CMI) can be done through probabilistic inference. In this work, a reliability-based I&M planning OWT is...

  2. Deficiencies in oxygen, carbon and chlorine (n, n'γ) cross sections and their impact on nuclear based inspection systems

    International Nuclear Information System (INIS)

    Large discrepancies have been found among the various nuclear libraries, mainly in the production cross sections and angular distributions of gamma-rays following neutron interactions. These data are required for the design and application of contraband inspection systems based on neutron irradiation techniques. As a result of these discrepancies experiments were conducted to correct and complement the required data. Cross section evaluations of carbon, oxygen and chlorine are reviewed and compared with existing and the new experimental data. ((orig.))

  3. Inspection planning

    International Nuclear Information System (INIS)

    Slovenian Nuclear Safety Administration (SNSA) division of nuclear and radiological safety inspection has developed systematic approach to their inspections. To be efficient in their efforts regarding regular and other types of inspections, in past years, the inspection plan has been developed. It is yearly based and organized on a such systematic way, that all areas of nuclear safety important activities of the licensee are covered. The inspection plan assures appropriate preparation for conducting the inspections, allows the overview of the progress regarding the areas to be covered during the year. Depending on the licensee activities and nature of facility (nuclear power plant, research reactor, radioactive waste storage, others), the plan has different levels of intensity of inspections and also their frequency. One of the basic approaches of the plan is to cover all nuclear and radiological important activities on such way, that all regulatory requests are fulfilled. In addition, the inspection plan is a good tool to improve inspection effectiveness based on previous experience and allows to have the oversight of the current status of fulfillment of planned inspections. Future improvement of the plan is necessary in the light of newest achievements on this field in the nuclear world, that means, new types of inspections are planned and will be incorporated into plan in next year.(author)

  4. Advanced Ultrasonic Inspection Techniques for General Purpose Heat Source Fueled Clad Closure Welds

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, M.W.

    2001-01-11

    A radioisotope thermoelectric generator is used to provide a power source for long-term deep space missions. This General Purpose Heat Source (GPHS) is fabricated using iridium clad vent sets to contain the plutonium oxide fuel pellets. Integrity of the closure weld is essential to ensure containment of the plutonium. The Oak Ridge Y-12 Plant took the lead role in developing the ultrasonic inspection for the closure weld and transferring the inspection to Los Alamos National Laboratory for use in fueled clad inspection for the Cassini mission. Initially only amplitude and time-of-flight data were recorded. However, a number of benign geometric conditions produced signals that were larger than the acceptance threshold. To identify these conditions, a B-scan inspection was developed that acquired full ultrasonic waveforms. Using a test protocol the B-scan inspection was able to identify benign conditions such as weld shield fusion and internal mismatch. Tangential radiography was used to confirm the ultrasonic results. All but two of 29 fueled clads for which ultrasonic B-scan data was evaluated appeared to have signals that could be attributed to benign geometric conditions. This report describes the ultrasonic inspection developed at Y-12 for the Cassini mission.

  5. Robotized Inspection of Vertical Structures of a Solar Power Plant Using NDT Techniques

    Directory of Open Access Journals (Sweden)

    Torsten Felsch

    2015-03-01

    Full Text Available Concentrated solar power (CSP plants are expansive facilities that require substantial inspection and maintenance. A fully automated inspection robot increases the efficiency of maintenance work, reduces operating and maintenance costs, and improves safety and work conditions for service technicians. This paper describes a climbing robot that is capable of performing inspection and maintenance on vertical surfaces of solar power plants, e.g., the tubes of the receiver in a central tower CSP plant. Specifically, the service robot’s climbing mechanism is explained and the results of the nondestructive inspection methods are reviewed. The robot moves on the panels of the receiver in the tower and aligns the sensors correctly for inspection. The vertical movement of the climbing kinematics is synchronized with the movement of the tower’s crane. Various devices that detect surface defects and thickness losses inside the tube were integrated into the robot. Since the tubes are exposed to very high radiation, they need to be inspected regularly.

  6. Electron Optic Design of Arrayed E-Beam Microcolumns Based Systems for Wafer Defects Inspection

    OpenAIRE

    Kazmiruk, V. V.; Savitskaja, T. N.

    2008-01-01

    In this paper is considered a matter of the system for wafer defect inspection (WDIS) practical realization. Such systems are on the agenda as the next generation and substitution for light optics and single $e$-beam based WDISs.

  7. Development of nondestructive evaluation techniques for DAM inspection. Progress report, January 1995 through August 1997

    Energy Technology Data Exchange (ETDEWEB)

    Brown, A. E.; Thomas, G.H.

    1997-09-04

    The Lawrence Livermore National Laboratory has concluded a two and a half year study on the development of an ultrasonic inspection system to inspect post stressed steel tendons on dams and flood gates. The inspection systems were part of a program for the California Department of Water Resources. The effort included the identification of the location and amount of corrosion damage to the tendons, identification of the cause of corrosion, and the technology for inhibiting corrosion. Several NDE methods for inspecting and quantifying damage to steel reinforced concrete water pipes were investigated and presented to the DWR for their consideration. The additional methods included Ground Penetrating RADAR, Electro- Potential Measurements, Infrared Technology, Pipe Inspection Crawlers (designed to travel inside pipelines and simultaneously report on the pipe condition as viewed by ultrasonic methods and video cameras from within the pipeline.) Reference to consultants hired by LLNL for similar on-site corrosion inspections were given to the DWR. The LLNL research into industries that have products to prevent corrosion resulted in the identification of an Innsbruck, Austria, company. This company claims to have products to permanently protect post- or pre-stressed tendons. The caveat is that the tendon protection system must be installed when the tendons are installed because no retrofit is available. Corrosion mitigation on the steel reinforcements surrounding the concrete was addressed through active and passive cathodic protection schemes. The combination of corrosion and erosion were addressed during consideration for the inspection of water-pump impeller-blades that are used in the three stage, million horsepower, pumping stations at Edmunston.

  8. Risk Based Optimal Inspection and Repair Planning for Ship Structures Subjected to Corrosion Deterioration

    Institute of Scientific and Technical Information of China (English)

    李典庆; 张圣坤; 唐文勇

    2004-01-01

    A framework of risk based inspection and repair planning was presented to optimize for the ship structures subjected to corrosion deterioration. The planning problem was formulated as an optimization problem where the expected lifetime costs were minimized with a constraint on the minimum acceptable reliability index. The safety margins were established for the inspection events, the repair events and the failure events for ship structures. Moreover, the formulae were derived to calculate failure probabilities and repair probabilities. Based on them, a component subjected to corrosion is investigated for illustration of the process of selecting the optimal inspection and repair strategy. Furthermore, some sensitivity studies were provided. The results show that the optimal inspection instants should take place before the reliability index reaches the minimum acceptable reliability index. The optimal target failure probability is 10-3. In addition, a balance can be achieved between the risk cost and total expected inspection and repair costs by means of the risk-based optimal inspection and repair method, which is very effective in selecting the optimal inspection and repair strategy.

  9. Tagged neutron inspection system (TNIS) based on portable sealed generators

    International Nuclear Information System (INIS)

    A prototype of portable sealed neutron generator has been recently built to deliver 14 MeV neutron beams tagged by a YAP:Ce α-particle detector. In order to produce simultaneously multiple neutron beams to irradiate complex samples, a study of the position sensitivity of the α-particle detector has been performed. Possible applications in non-destructive analysis and future developments of the tagged neutron inspection system (TNIS) concept are discussed

  10. NDT method in determining the rate of corrosion applicable to risk based inspection

    International Nuclear Information System (INIS)

    Corrosion is a major problem in oil and gas industries, refineries and chemical process plants as the equipment is often exposed to corrosive environments or elevated temperature. Important equipment need to operate safely and reliably to avoid injuries to personnel and the public, and to prevent loss time and cost incurred due to loss of production and shutdown. The paper assess the approach in evaluating the technique of non-destructive testing (NDT) using Ultrasonic Testing (UT) in determining the rate of corrosion and remaining life of equipment applicable to Risk Based Inspection (RBI). Methods in determining the corrosion rate are presented using analytical method. Examples and data from MINT chiller water pipeline are presented to illustrate the application of these methods. (Author)

  11. Application of risk based inspection as a part of life management of nuclear power plants

    International Nuclear Information System (INIS)

    Full text: Risk Informed approach is a systematic effort to improve plant safety in a more efficient manner by distributing the available safety resources depending on the importance to plant safety. This approach has found immense application in various aspects associated with Nuclear Power Plants, including design, manufacturing, operation and regulation. Typical applications of Risk Informed approach are in Technical Specification, In-Service Inspection (ISI) requirements, Motor Operated Valve testing, Configuration Control etc. In order to cater to such variety of Probabilistic Safety Assessment (PSA) based Risk Informed requirements, a software package, 'Risk Monitor' has been developed by the authors. An important application of Risk informed approach that has been undertaken for Indian Pressurised Heavy Water Reactor (IPHWR) is towards Risk Informed In-Service Inspection (RI-ISI). Studies are being conducted to evolve an inspection plan that is optimised to provide effective inspections at the right location with a proper inspection frequency. Using risk informed approach, the identification of system / component for inspection resource allocation is based on the results from Level 1 PSA of a NPP. Even though this methodology can be employed on any of the nuclear components/systems such as mechanical systems, instrumentation, etc., as a starting point, piping has been considered for employing Risk Informed Inspection. Plant risk assessment is modelled through the analysis of Core Damage Frequency (CDF) using PSA models. Risk Informed Inspection program of piping involves the estimation of failure probability or frequency of a piping segment and estimation of consequences of piping failures. ISI program changes could affect the failure probability values of piping and can introduce a change in CDF. These effects can be brought out through the implementation of Risk Informed inspection strategy. Various importance measures like Fussel-Vesely, Birnbaum

  12. Combined electromagnetic techniques in inspection of pump rod; Tecnicas eletromagneticas combinadas na inspecao de hastes de bombeio

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Francisco Carlos Rodrigues; Martins, Marcus Vinicius Maciel [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    1998-07-01

    This work describes the experience acquired with the ground production installation of the PETROBRAS, state of Bahia, Brazil, where a procedures has been applied for rod inspection by using a semi-automatic electromagnetic technique, combined with magnetic particles test. Up to the present, this procedure is giving results which are technically promisers. Under the strictly economic viewpoint, some doubts were raised related to the establishing of the optimum point to the utilization.

  13. In service inspection of pipes based on risk methods; Inspeccion en servicio de tuberias basada en metodos de riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza G, G.; Viais J, J.; Carmona C, M. [ININ, Centro Nuclear ' Dr. Nabor Carrillo Flores' , Carretera Mexico Toluca, S/N. La Marquesa, Ocoyoacac, Mexico, C. P. 52750 (Mexico)]. e-mail: gmg@nuclear.inin.mx

    2006-07-01

    The politics of the Nuclear Regulatory Commission (by its initials in English NRC) of the United States of America on the use of the Probabilistic Safety Analysis (PSA) in activities of nuclear regulation it foments the use of this analysis technique to improve the decisions making, to reduce the unnecessary work in maintenance aspects, inspection and tests and to improve the regulatory efficiency. The inspection programs in service (ISI by its initials in English) developed by the American Society of Mechanical Engineers (by its initials in English ASME) it has been the one primary mechanism to prove the mechanical equipment in plants of nuclear energy, these programs indeed have been carried out in plants of nuclear energy by more of two decades. Their purpose is to identify the conditions, such as indications of cracks that are precursory of flights and ruptures which violate the integrity principles of the pressure frontier. The inspection in service activities include ultrasonic tests, surface tests and penetrating liquids test, also activities that include the scaffolds construction, removal of insulations and welding polishing. The inspections in service every 18 months during the times outside of service are executed. One of the objectives is to lower the costs of the inspections during the times outside of service and to reduce the exposure to the radiation by part of the personnel during these times out for inspections, while it is increased or it maintains the personnel's safety and the reliability. As part of the methodology a pipe segment is selected for which a fault in any point has the same consequences, being calculated the fault probability of the tube using the dimensions of the segment. In this work the inspection in service methodology is applied based on risk to an aspersion system of low pressure of the Laguna Verde Nucleo electric Central. For this system a reduction in the number of welding to inspect of 103 to only 15 is obtained

  14. Wavelet Based Image Denoising Technique

    Directory of Open Access Journals (Sweden)

    Sachin D Ruikar

    2011-03-01

    Full Text Available This paper proposes different approaches of wavelet based image denoising methods. The search for efficient image denoising methods is still a valid challenge at the crossing of functional analysis and statistics. In spite of the sophistication of the recently proposed methods, most algorithms have not yet attained a desirable level of applicability. Wavelet algorithms are useful tool for signal processing such as image compression and denoising. Multi wavelets can be considered as an extension of scalar wavelets. The main aim is to modify the wavelet coefficients in the new basis, the noise can be removed from the data. In this paper, we extend the existing technique and providing a comprehensive evaluation of the proposed method. Results based on different noise, such as Gaussian, Poisson’s, Salt and Pepper, and Speckle performed in this paper. A signal to noise ratio as a measure of the quality of denoising was preferred.

  15. Development of signal processing technique for inspection of defects in stud bolts of nuclear reactor vessel

    International Nuclear Information System (INIS)

    Bolt failure is a hazard factor for the safety of reactor vessels in nuclear power plants. However, in the practical application of ultrasonic technique for crack detection in stud bolt, the classification of crack signal from the signals reflected from threads in stud bolt is very difficult. In this study, shadow effect technique combined with new signal processing method has been investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of new signal processing concept is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different from the reference signals. It has shown that the small flaws can be effectively detected by novel ultrasonic technique combined with this new signal processing concept.

  16. Development of signal processing technique for inspection of defects in stud bolts of nuclear reactor vessel

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Hyun Deok; Lee, Joon Hyun; Choi, Sang Woo; Cho, Youn Ho [Pusan National University, Pusan (Korea, Republic of); Park, Moon Ho [Korea Plant Service and Engineering Co.,Ltd, Sungnam (Korea, Republic of)

    2004-05-15

    Bolt failure is a hazard factor for the safety of reactor vessels in nuclear power plants. However, in the practical application of ultrasonic technique for crack detection in stud bolt, the classification of crack signal from the signals reflected from threads in stud bolt is very difficult. In this study, shadow effect technique combined with new signal processing method has been investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of new signal processing concept is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different from the reference signals. It has shown that the small flaws can be effectively detected by novel ultrasonic technique combined with this new signal processing concept.

  17. Research on automatic inspection system for defects on precise optical surface based on machine vision

    Institute of Scientific and Technical Information of China (English)

    WANG Xue; XIE Zhi-jiang

    2006-01-01

    In manufacture of precise optical products, it is important to inspect and classify the potential defects existing on the products' surfaces after precise machining in order to obtain high quality in both functionality and aesthetics. The existing methods for detecting and classifying defects all are low accuracy or efficiency or high cost in inspection process. In this paper, a new inspection system based on machine vision has been introduced, which uses automatic focusing and image mosaic technologies to rapidly acquire distinct surface image, and employs Case-Based Reasoning(CBR)method in defects classification. A modificatory fuzzy similarity algorithm in CBR has been adopted for more quick and robust need of pattern recognition in practice inspection. Experiments show that the system can inspect surface diameter of 500mm in half an hour with resolving power of 0.8μm diameter according to digs or 0.5μm transverse width according to scratches. The proposed inspection principles and methods not only have meet manufacturing requirements of precise optical products, but also have great potential applications in other fields of precise surface inspection.

  18. In-Service Inspection of Wall-thinned Defects Using a Lock-in Technique of IR Thermography

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Kwae Hwan; Kim, Ju Hyun; Na, Man Gyun; Kim, Jin Weon [Chosun Univ., Gwangju (Korea, Republic of)

    2013-10-15

    In this study, a lock-in technique and power adjustment were applied to the cooling device for the IR thermography in order to detect the wall-thinned defects of the pipe specimen in a normal operation NPPs. According as the number of the cooling devices is increased and air volume transferred by the cooling device increases, wall-thinned defects inside pipes are more visible. By cooling the pipe using a lock-in technique in IR thermography, the boundary of the wall-thinned defective part is clear and the defect detection is easy. It is expected to detect the wall-thinned defects of piping during normal operation, to shorten the maintenance time of the NPPs, and to improve the work efficiency of the inspector. Recently, the safety problem of nuclear power plants (NPPs) has emerged as a global concern. As a result, the secondary system equipment in long-term aged NPPs has been growing interest. For these reasons, NDT for checking the integrity of the secondary system equipment is performed. The infrared (IR) thermography is one of the NDT. It is possible for us to solve the problems of the existing NDT. IR thermography can detect without contact the wall-thinned defects in pipes. Also, IR thermography using a lock-in technique for inspection is much safer and faster than other techniques. It is expected to be able to accurately detect the boundary of the non-defect parts and the defect parts, and shows a high utilization in the industrial field. Through this study, we have developed the inspection technique that can detect the defects by using the lock-in technique in IR thermography for inspection of pipes in the NPPs during the normal operation.

  19. In-Service Inspection of Wall-thinned Defects Using a Lock-in Technique of IR Thermography

    International Nuclear Information System (INIS)

    In this study, a lock-in technique and power adjustment were applied to the cooling device for the IR thermography in order to detect the wall-thinned defects of the pipe specimen in a normal operation NPPs. According as the number of the cooling devices is increased and air volume transferred by the cooling device increases, wall-thinned defects inside pipes are more visible. By cooling the pipe using a lock-in technique in IR thermography, the boundary of the wall-thinned defective part is clear and the defect detection is easy. It is expected to detect the wall-thinned defects of piping during normal operation, to shorten the maintenance time of the NPPs, and to improve the work efficiency of the inspector. Recently, the safety problem of nuclear power plants (NPPs) has emerged as a global concern. As a result, the secondary system equipment in long-term aged NPPs has been growing interest. For these reasons, NDT for checking the integrity of the secondary system equipment is performed. The infrared (IR) thermography is one of the NDT. It is possible for us to solve the problems of the existing NDT. IR thermography can detect without contact the wall-thinned defects in pipes. Also, IR thermography using a lock-in technique for inspection is much safer and faster than other techniques. It is expected to be able to accurately detect the boundary of the non-defect parts and the defect parts, and shows a high utilization in the industrial field. Through this study, we have developed the inspection technique that can detect the defects by using the lock-in technique in IR thermography for inspection of pipes in the NPPs during the normal operation

  20. Intercomparison of techniques for inspection and diagnostics of heavy water reactor pressure tubes. Determination of hydrogen concentration and blister characterization

    International Nuclear Information System (INIS)

    Heavy water reactors (HWRs) comprise significant numbers of today's operating nuclear power plants, and more are under construction. Efficient and accurate inspection and diagnostic techniques for various reactor components and systems, especially pressure tubes, are an important factor in ensuring reliable and safe plant operation. To foster international collaboration in the efficient and safe use of nuclear power, the IAEA conducted a Coordinated Research Project (CRP) on Intercomparison of Techniques for HWR Pressure Tube Inspection and Diagnostics. This CRP was carried out within the framework of the IAEA's Technical Working Group on Advanced Technologies for HWRs (the TWG-HWR). The TWG-HWR is a group of experts nominated by their governments and designated by the IAEA to provide advice and to support implementation of IAEA's project on advanced technologies for HWRs. The objective of the CRP was to compare non-destructive inspection and diagnostic techniques, in use and being developed, for structural integrity assessment of HWR pressure tubes. During the first phase of this CRP participants investigated the capability of different techniques to detect and characterize flaws. During the second phase participants collaborated to detect and characterize hydride blisters and to determine the hydrogen concentration in zirconium alloys. The intention was to identify the most effective pressure tube inspection and diagnostic methods and to identify further development needs. The organizations which participated in phase 2 of this CRP are: - Comision Nacional de Energia Atomica (CNEA), Argentina; - Atomic Energy of Canada Ltd. (AECL), Chalk River Laboratories (CRL), Canada; - Bhabha Atomic Research Centre (BARC), India; - Korea Atomic Energy Research Institute (KAERI), Republic of Korea; - National Institute for Research and Development for Technical Physics (NIRDTP), Romania; - Nuclear Non-Destructive Testing Research and Services (NNDT), Romania. IAEA-TECDOC-1499

  1. Camera Based 3D Mine-Shaft Inspection System

    OpenAIRE

    Wohlfeil, Jürgen; Spreckels, Volker; Strackenbrock, Bernhard; Schlienkamp, Andreas; Choinowski, André

    2015-01-01

    This paper describes the development of an Optical 3D Shaft Inspection System needed for the survey and monitoring of Water Handling Shafts in the German Ruhrgebiet. The development is part of the RAG R&D project “ABSMon”. The end of the German hard coal mining at the end of 2018 has been determined with the Steinkohlefinanzierungsgesetz (SteinkohleFinG) from 2007-12-20. About three hundred years before now the near surface hard coal mining began in the southern Ruhr Area an...

  2. An artificial immune approach for optical image based vision inspection

    Institute of Scientific and Technical Information of China (English)

    Hong Zheng(郑宏); Nanfeng Xiao(肖南风); Jinhui Lan(蓝金辉)

    2003-01-01

    This paper presents a novel approach of visual inspection for texture surface defects. The approach usesartificial immune theory in learning the detection of texture defects. In this paper, texture defects areregards as non-self, and normal textures are regarded as self. Defect filters and segmentation thresholdsused for defect detection are regarded as antibodies. The clonal selection algorithm stemmed from thenatural immune system is employed to learn antibodies. Experimental results on textile image inspectionare presented to illustrate the merit and feasibility of the proposed method.

  3. Research and development on plant inspection presentation system cooperative with mobile robots and maintenance knowledge base

    International Nuclear Information System (INIS)

    In order to upgrade safety and reliability of nuclear power plants it is very important to develop a system of early detection of anomalies and realize adequate inspections responding to them. Based on accumulated basic technologies of cooperative active sensing systems for autonomous inspection mobile robots having active visual sensing and acoustic sensors with movable lighting and intelligent multimodal systems, 3D data processing visualization transmission technologies have been incorporated for compact storage of time and space dependent enormous inspection knowledge base. Surrounding server, simulating plant's environments with mobile robots and mockup systems, has been prepared and tested to realize this concept. Long-term operation of the server will be needed to accumulate inspection database and their efficient utilization. (T. Tanaka)

  4. Design of inspection and maintenance models based on the CCC-chart

    OpenAIRE

    Chan, LY

    2003-01-01

    In this research, six maintenance models are constructed based on whether minor inspection, major inspection, minor maintenance and major maintenance are performed on a system. The system to study is a production process in which items produced can be classified as either conforming or nonconforming, and a statistical process control chart called CCC-chart (cumulative count control chart) can be applied to monitor the process. The maintenance models are analyzed quantitatively, and selection ...

  5. Intelligent Automated Nuclear Fuel Pellet Inspection System

    International Nuclear Information System (INIS)

    At the present time, nuclear pellet inspection is performed manually using naked eyes for judgment and decisionmaking on accepting or rejecting pellets. This current practice of pellet inspection is tedious and subject to inconsistencies and error. Furthermore, unnecessary re-fabrication of pellets is costly and the presence of low quality pellets in a fuel assembly is unacceptable. To improve the quality control in nuclear fuel fabrication plants, an automated pellet inspection system based on advanced techniques is needed. Such a system addresses the following concerns of the current manual inspection method: (1) the reliability of inspection due to typical human errors, (2) radiation exposure to the workers, and (3) speed of inspection and its economical impact. The goal of this research is to develop an automated nuclear fuel pellet inspection system which is based on pellet video (photographic) images and uses artificial intelligence techniques

  6. Evaluation of eddy current and magnetic techniques for inspecting rebars in bridge barrier rails

    Science.gov (United States)

    Lo, C. C. H.; Nakagawa, N.

    2013-01-01

    This paper reports on a feasibility study of using eddy current (EC) and magnetic flux leakage (MFL) methods to detect corrosion damage in rebars that anchor concrete barrier rails to the road deck of bridge structures. EC and MFL measurements were carried out on standalone rebars with and without artificial defects of 25% and 50% material loss, using a commercial EC-based rebar locator and a MFL system that was developed using giant magnetoresistance sensors to detect leakage fluxes from the defects. Both techniques can readily detect the defects at a distance of 2.5″ (63.5 mm). The amplitudes of the EC and MFL signals vary monotonically with the amount of material loss, indicating the potential of using the techniques to quantify material loss of standalone rebars.

  7. Development of an automatic post-weld inspection system based on laser vision

    Institute of Scientific and Technical Information of China (English)

    Fu Xibin; Lin Sanbao; Fan Chenglei; Yang Chunli; Luo Lu

    2008-01-01

    In order to overcome the limitations of manual post-weld visual inspection approach, an automated inspection system is developed which uses three-dimensional laser vision system based on the principle of optical triangulation. The system hardware consists of a modular development kit (MDK), a computer, an actuating mechanism and so on. In image processing algorithms, extraction accuracy of centric line of laser stripe is the critical factor that determines the system performance. So according to the features of laser stripe image, a novel algorithm is developed to detect the central line of laser stripe fast and accurately. Experiments have demonstrated that this system can be used in various weld features inspection of both butt and fillet types of weld. Compared with traditional manual inspection method, this method has obvious dominance. The three-dimensional reconstruction result shows that this system has high accuracy and reliability.

  8. A Bevel Gear Quality Inspection System Based on Multi-Camera Vision Technology.

    Science.gov (United States)

    Liu, Ruiling; Zhong, Dexing; Lyu, Hongqiang; Han, Jiuqiang

    2016-01-01

    Surface defect detection and dimension measurement of automotive bevel gears by manual inspection are costly, inefficient, low speed and low accuracy. In order to solve these problems, a synthetic bevel gear quality inspection system based on multi-camera vision technology is developed. The system can detect surface defects and measure gear dimensions simultaneously. Three efficient algorithms named Neighborhood Average Difference (NAD), Circle Approximation Method (CAM) and Fast Rotation-Position (FRP) are proposed. The system can detect knock damage, cracks, scratches, dents, gibbosity or repeated cutting of the spline, etc. The smallest detectable defect is 0.4 mm × 0.4 mm and the precision of dimension measurement is about 40-50 μm. One inspection process takes no more than 1.3 s. Both precision and speed meet the requirements of real-time online inspection in bevel gear production. PMID:27571078

  9. A real-time surface inspection system for precision steel balls based on machine vision

    Science.gov (United States)

    Chen, Yi-Ji; Tsai, Jhy-Cherng; Hsu, Ya-Chen

    2016-07-01

    Precision steel balls are one of the most fundament components for motion and power transmission parts and they are widely used in industrial machinery and the automotive industry. As precision balls are crucial for the quality of these products, there is an urgent need to develop a fast and robust system for inspecting defects of precision steel balls. In this paper, a real-time system for inspecting surface defects of precision steel balls is developed based on machine vision. The developed system integrates a dual-lighting system, an unfolding mechanism and inspection algorithms for real-time signal processing and defect detection. The developed system is tested under feeding speeds of 4 pcs s‑1 with a detection rate of 99.94% and an error rate of 0.10%. The minimum detectable surface flaw area is 0.01 mm2, which meets the requirement for inspecting ISO grade 100 precision steel balls.

  10. Development of nuclear fuel rod inspection technique using ultrasonic resonance phenomenon

    International Nuclear Information System (INIS)

    Acoustic resonance scattering from a nuclear fuel rod in water is analyzed. A new model for the background which is attributed to the interference of reflected wave and diffracted wave is found and here named the inherent background. The resonance spectrum of a fuel rod is obtained by subtracting the inherent background from the scattered pressure. And also analyzed are the effect of material damping of cladding tube and pellet on the resonance spectrum of a fuel rod. The propagation characteristics of circumferential waves which cause the resonances of cladding tube is produced and the appropriate resonance modes for the application to the inspection of assembled fuel rods are selected. The resonance modes are experimentally measured for pre- and post-irradiated fuel rods and the validation of the fuel rod inspection using ultrasonic resonance phenomenon is examined. And thin ultrasonic sensors accessible into the narrow interval (about 2-3mm) between assembled fuel rods are designed and manufactured. 14 refs. (Author)

  11. Innovative image processing techniques applied to the thermographic inspection of PFC with SATIR facility

    International Nuclear Information System (INIS)

    The components used in fusion devices, especially high heat flux Plasma Facing Components (PFC), have to withstand heat fluxes in the range of 10-20 MW/m2. So, they require high reliability which can be only guaranteed by accurate Non Destructive Examinations (NDE). The SATIR test bed operating at Commissariat a l'Energie Atomique (CEA) Cadarache performs NDE using transient infrared thermography sequence which compares the thermal response of a tested element to a Reference element assumed to be defect free. The control parameter is called DTrefmax. In this paper, we present two innovative image processing techniques of the SATIR signal allowing the qualification of a component without any Reference element. The first method is based on a spatial image autocorrelation and the second on the resolution of an Inverse Heat Conduction Problem (IHCP) using a BEM (Boundary Element Method) technique. After a validation step performed on numerical data, these two methods have been applied to SATIR experimental data. The results show that these two techniques allow accurate defect detection, without using a Reference tile. They can be used in addition to the DTrefmax, for the qualification of plasma facing components.

  12. Recent developments of non-destructive inspection techniques in Takasago R/D center

    International Nuclear Information System (INIS)

    Eddy current testing (ECT) has been widely used in in-service-inspection of generator tubes in nuclear power plants. A bobbin coil probe is mainly and routinely used for fully length inspection of all SG tubes in Japan. From the view point of delectability, a mechanically rotating pancake probe is superior among various ECT probes. Therefore, it is highly desirable to develop a new ECT probe which has similar performance to them rotating pancake probe and has similar capability in actual inspection speed to the bobbin coil probe. In this paper, we will explain the new ECT probe. Main results are as follows. (1) It was shown that the new probe with 4 detecting coils and one slant exciting coil was superior in flaw delectability compared with various kinds of conventional probes. (2) It was shown that electric circuits of amplifiers, multiplexer and so on in the probe itself was very useful to reduce the number of signal cables from detecting coils and to increase signal to noise ratio. (3) we designed and made the ECT probe with thin film coils for detecting coils and with miniaturized electric circuits. In experiments, the prototype probe could detect successfully both axial and circumferential EDM notch of 20% tube thickness. It is confirmed that thin film coils have potential to be used for the new ECT probes and basic functions of electric circuits work very well. (Authors)

  13. Non-destructive inservice inspections

    International Nuclear Information System (INIS)

    In order to assess the possible damages occurring in the components and structures of operating nuclear power plants during service the main components and structures are periodically inspected by non-destructive testing techniques. The reliability of non-destructive testing techniques applied in these inservice inspections is of major importance because the decisions concerning the needs for repair of components are mainly based on the results of inspections. One of the targets of this research program has been to improve the reliability of non-destructive testing. This has been addressed in the sub-projects which are briefly summarised here. (author)

  14. Development and validation of a real-time SAFT-UT [synthetic aperture focusing technique for ultrasonic testing] system for the inspection of light water reactor components: Annual report, October 1985-September 1986

    International Nuclear Information System (INIS)

    The Pacific Northwest Laboratory is working to design, fabricate, and evaluate a real-time flaw detection and characterization system based on the synthetic aperture focusing technique for ultrasonic testing (SAFT-UT). The system is designed to perform inservice inspection of light-water reactor components. Included objectives of this program for the Nuclear Regulatory Commission are to develop procedures for system calibration and field operation, to validate the system through laboratory and field inspections, and to generate an engineering data base to support ASME Code acceptance of the technology. This progress report covers the programmatic work from October 1985 through September 1986. 45 figs., 8 tabs

  15. 3D VISION-BASED DIETARY INSPECTION FOR THE CENTRAL KITCHEN AUTOMATION

    Directory of Open Access Journals (Sweden)

    Yue-Min Jiang

    2014-12-01

    Full Text Available This paper proposes an intelligent and automatic dietary inspection system which can be applied to the dietary inspection for the application of central kitchen automation. The diet specifically designed for the patients are required with providing personalized diet such as low sodium intake or some necessary food. Hence, the proposed system can benefit the inspection process that is often performed manually. In the proposed system, firstly, the meal box can be detected and located automatically with the vision-based method and then all the food ingredients can be identified by using the color and LBP-HF texture features. Secondly, the quantity for each of food ingredient is estimated by using the image depth information. The experimental results show that the dietary inspection accuracy can approach 80%, dietary inspection efficiency can reach1200ms, and the food quantity accuracy is about 90%. The proposed system is expected to increase the capacity of meal supply over 50% and be helpful to the dietician in the hospital for saving the time in the diet inspection process.

  16. Potential of Uav-Based Laser Scanner and Multispectral Camera Data in Building Inspection

    Science.gov (United States)

    Mader, D.; Blaskow, R.; Westfeld, P.; Weller, C.

    2016-06-01

    Conventional building inspection of bridges, dams or large constructions in general is rather time consuming and often cost expensive due to traffic closures and the need of special heavy vehicles such as under-bridge inspection units or other large lifting platforms. In consideration that, an unmanned aerial vehicle (UAV) will be more reliable and efficient as well as less expensive and simpler to operate. The utilisation of UAVs as an assisting tool in building inspections is obviously. Furthermore, light-weight special sensors such as infrared and thermal cameras as well as laser scanner are available and predestined for usage on unmanned aircraft systems. Such a flexible low-cost system is realized in the ADFEX project with the goal of time-efficient object exploration, monitoring and damage detection. For this purpose, a fleet of UAVs, equipped with several sensors for navigation, obstacle avoidance and 3D object-data acquisition, has been developed and constructed. This contribution deals with the potential of UAV-based data in building inspection. Therefore, an overview of the ADFEX project, sensor specifications and requirements of building inspections in general are given. On the basis of results achieved in practical studies, the applicability and potential of the UAV system in building inspection will be presented and discussed.

  17. Intercomparison of techniques for inspection and diagnostics of heavy water reactor pressure tubes: Flaw detection and characterization [Phase 1

    International Nuclear Information System (INIS)

    Nuclear power plants with heavy water reactors (HWRs) comprise nine percent of today's operating nuclear units, and more are under construction. Efficient and accurate inspection and diagnostic techniques for various reactor components and systems are an important factor in assuring reliable and safe plant operation. To foster international collaboration in the efficient and safe use of nuclear power, the IAEA conducted a Coordinated Research Programme (CRP) on Inter-comparison of Techniques for HWR Pressure Tube Inspection and Diagnostics. This CRP was carried out within the frame of the IAEA Department of Nuclear Energy's Technical Working Group on Advanced Technologies for HWRs (the TWG-HWR). The TWG-HWR is a group of experts nominated by their governments and designated by the IAEA to provide advice and to support implementation of the IAEA's project on advanced technologies for HWRs. The objective of the CRP was to inter-compare non-destructive inspection and diagnostic techniques, in use and being developed, for structural integrity assessment of HWR pressure tubes. During the first phase of this CRP, participants have investigated the capability of different techniques to detect and characterize flaws. During the second phase of this CRP, participants collaborated to detect and characterize hydride blisters and to determine the hydrogen concentration in Zirconium alloys. The intent was to identify the most effective pressure tube inspection and diagnostic methods, and to identify further development needs. The organizations that have participated in this CRP are: - The Comision Nacional de Energia Atomica (CNEA), Argentina; - Atomic Energy of Canada Ltd. (AECL); Chalk River Laboratories (CRL), Canada; - The Research Institute of Nuclear Power Operations (RINPO), China National Nuclear Corporation (CNNC), China; - Bhabha Atomic Research Centre (BARC), India; - The Korea Electric Power Research Institute (KEPRI), Republic of Korea; - The Korea Atomic Energy

  18. GASVOL 18'' gas pipeline - risk based inspection study

    Energy Technology Data Exchange (ETDEWEB)

    Bjoernoey, Ola H.; Etterdal, Birger A. [Det Norske Veritas (DNV), Oslo (Norway); Guarize, Rosimar; Oliveira, Luiz F.S. [Det Norske Veritas (DNV) (Brazil); Faertes, Denise; Dias, Ricardo [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    This paper describes a risk based approach and inspection planning as part of the Pipeline Integrity Management (PIM) system for the 95.5 km long 18'' GASVOL gas pipeline in the South eastern region of Brazil transporting circa 5 000 000 m3 dry gas per day. Pipeline systems can be subject to several degradation mechanisms and inspection and monitoring are used to ensure system integrity. Modern pipeline regulations and codes are normally based on a core safety or risk philosophy. The detailed design requirements presented in design codes are practical interpretations established so as to fulfill these core objectives. A given pipeline, designed, constructed and installed according to a pipeline code is therefore the realization of a structure, which, along its whole length, meets the applicable safety objectives of that code. The main objective of Pipeline Integrity Management (PIM) is to control and document the integrity of the pipeline for its whole service life, and to do this in a cost-effective manner. DNV has a specific approach to RBI planning, starting with an initial qualitative assessment where pipelines and damage type are ranked according to risk and potential risk reduction by an inspection and then carried forward to a quantitative detailed assessment where the level of complexity and accuracy can vary based on availability of information and owner needs. Detailed assessment requires significant effort in data gathering. The findings are dependent upon the accuracy of the inspection data, and on DNV's interpretation of the pipeline reference system and simplifications in the inspection data reported. The following specific failure mechanisms were investigated: internal corrosion, external corrosion, third party interference, landslides and black powder. RBI planning, in general words, is a 'living process'. In order to optimize future inspections, it is essential that the analyses utilize the most recent information regarding

  19. Cargo inspection system based on pulsed fast neutron analysis

    Science.gov (United States)

    Brown, Douglas R.; Coates, Allison; Kuo, Stelly N.; Loveman, Robert; Pentaleri, Ed; Rynes, Joel C.

    1997-02-01

    The pulsed fast neutron analysis (PFNA) cargo inspection system (CIS) uses a nanosecond pulsed beam of fast neutrons to interrogate the contents of small volume elements -- voxels -- of a cargo container or truck. A color display shows the three-dimensional location of suspected contraband, such as drugs or explosives. The neutrons interact with the elemental contents of each vowel, and gamma rays characteristic of the elements are collected in an array of detectors. The elemental signals and their ratios give unique signatures for drugs and other contraband. From the time of arrival of the gamma rays, the position of the vowel within the truck is determined. The PFNA CIS is designed to scan five or more trucks per hour. The operator interface has been designed to assist in the rapid identification of drugs, explosives or other contraband. This paper describes the system and the tests for drugs and explosives that have been carried out during the past year. These tests were aimed at exploring the envelope of performance of the system.

  20. Robotized system for in-pipe inspection using pressure tolerant electronics technique

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ramon R.; Hsu, Liu; Peixoto, Alessandro J.; Gomes, Luiz P.C.S. [Coordenacao dos Programas de Pos-graduacao de Engenharia (UFRJ/COPPE), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Eletrica. Grupo de Simulacao e Controle em Automacao e Robotica (GSCAR)]. E-mail: ramon, liu, jacoud, lpgomes@coep.ufrj.br; Reis, Ney R.S. dos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Lab. de Robotica]. E-mail: salvireis@cenpes.petrobras.com.br

    2003-07-01

    This paper reports the development and experimental evaluation of a robotized system devised to perform two kinds of measurements inside a pipeline: the thickness of the internal wall painting layer and the internal radius. The thickness measurement allows the inspection of the painting layer quality and by measuring several radii it is possible to estimate the pipeline transversal section shape. The proposed scheme is shown to yield very satisfactory results on an actual 14'' (inches) pipeline in a real site. (author)

  1. Cost Optimal Reliability Based Inspection and Replacement Planning of Piping Subjected to CO2 Corrosion

    DEFF Research Database (Denmark)

    Hellevik, S. G.; Langen, I.; Sørensen, John Dalsgaard

    1999-01-01

    A methodology for cost optimal reliability based inspection and replacement planning of piping subjected to CO2 corrosion is described. Both initial (design phase) and in-service planning are dealt with. The methodology is based on the application of methods for structural reliability analysis...

  2. Risk-Based Inspection and Maintenance Planning Optimization of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ramírez, José G. Rangel; Sørensen, John Dalsgaard

    2009-01-01

    A risk-based inspection planning (RBI) approach applied to offshore wind turbines (OWT) is presented, based on RBI methodology developed in the last decades in the oil and gas industry. In wind farm (IWF) and single-alone locations are considered using a code-established turbulence models includi...

  3. Pre-service and inservice inspection of heat exchanger tube bundles by means of ultrasonics; A new and powerful technique

    International Nuclear Information System (INIS)

    For the inservice inspection of ferritic steam generator tubes of LFMBR's a new and complete inservice inspection system has been developed, based upon ultrasound. This method measures wallthickness and registrates eventually faulting areas in one and the same relatively fast run in all kinds of tube geometries. In addition its potential to recognize, to size and to evaluate even very small eefects appears to be very large. The system shows a very good defect detection reliability and it can be applied in most areas where eddy current meets either unfriendly conditions or cannot even be applied. On-line data handling provides the desired output even in graphical representation directly after the measurements have been made

  4. Monitoring and inspection techniques for long term storage of higher activity waste packages

    International Nuclear Information System (INIS)

    In 2009, following recent changes in United Kingdom (UK) Government Policy, the Nuclear Decommissioning Authority (NDA) identified a knowledge gap in the area of long term interim storage of waste packages. A cross-industry Integrated Project Team (IPT) for Interim Storage was created with responsibility for delivering Industry Guidance on the storage of packaged Higher Activity Waste (HAW) for the current UK civil decommissioning and clean-up programmes. This included a remit to direct research and development projects via the NDA's Direct Research Portfolio (DRP) to fill the knowledge gap. The IPT for Interim Storage published Industry Guidance in 2012 which established a method to define generic package performance criteria and made recommendations on monitoring and inspection. The package performance method consists of the following steps; identification of the package safety function, identification of evolutionary processes that may affect safety function performance, determination of measurable indicators of these evolutionary processes and calibration of the indicators into package performance zones. This article provides an overview of three projects funded by the NDA's DRP that the UK National Nuclear Laboratory (NNL) have completed to address monitoring and inspection needs of waste packages in interim storage. (orig.)

  5. Risk-based Inspection Guide for the Susquehanna Station HPCI system

    International Nuclear Information System (INIS)

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A system Risk-based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Susquehanna Steam Electric Station (SSES) which is operated by Pennsylvania Power ampersand Light (PP ampersand L). Included in this S-RIG is a discussion of the role of HPCI in mitigating accidents and a presentation of PRA-based failure modes which could prevent proper operation of the system. The S-RIG uses industry operating experience, including plant-specific illustrative examples, to augment the basic PRA failure modes. It is designed to be used as a reference for both routine inspections and the evaluation of the significance of component failures

  6. Risk-based Inspection Guide for the Susquehanna Station HPCI system

    Energy Technology Data Exchange (ETDEWEB)

    Travis, R; Higgins, J; Gunther, W; Shier, W [Brookhaven National Lab., Upton, NY (United States)

    1992-11-01

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A system Risk-based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Susquehanna Steam Electric Station (SSES) which is operated by Pennsylvania Power & Light (PP&L). Included in this S-RIG is a discussion of the role of HPCI in mitigating accidents and a presentation of PRA-based failure modes which could prevent proper operation of the system. The S-RIG uses industry operating experience, including plant-specific illustrative examples, to augment the basic PRA failure modes. It is designed to be used as a reference for both routine inspections and the evaluation of the significance of component failures.

  7. Nondestructive, in-process inspection of inertia friction welding : an investigation into a new sensing technique.

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, D. A. (Daniel A.); Cola, M. J. (Mark J.); Dave, V. R. (Vivek R.); Dozhier, N. G. (Nathan G.); Carpenter, R. W. (Robert W.)

    2002-01-01

    This paper investigates the capabilities of a new sensor for in-process monitoring of quality during friction welding. The non-contact sensor is composed of microphones that are mounted in an aluminum ring which surrounds the weld joint. The sensor collects the acoustical energy (in the form of sound pressure) that is emitted during the plastic deformation and phase transformations (if applicable) in friction welding processes. The focus in this preliminary investigation is to search for and identify features within the acoustical emission that are indicative of bond quality. Bar-to-bar inertia friction welding (one form of friction welding) of copper to 304L stainless steel is used in this proof-of-concept study. This material combination exhibits only marginal weldability and is ideally suited for validating the capabilities of this new sensing technique. A probabilistic neural network is employed in this work to analyze the acoustical emission's frequency spectrum in an attempt to classify acceptable, conditional, and unacceptable welds. Our preliminary findings indicate that quality-based process features do exist within the frequency spectrum of the acoustical signature. The results from this analysis are presented. Future work in improving the sensing and interpretation of the data is discussed in an effort to develop a robust method of quality-based, in-process monitoring of friction welds.

  8. Risk-based prioritization and its application to inspection of valves in the water sector

    International Nuclear Information System (INIS)

    Isolation valves facilitate the effective operation and maintenance of water supply networks, but their sheer number presents a significant asset management challenge. If left unmanaged, valve reliability issues can become widespread. Inspections provide a means of increasing reliability, but a survey of industry practices indicated that some utilities did not have such a program in place. To improve asset management and reduce business risk exposure, such utilities need an effective means of commencing inspection programs. From a theoretical perspective, risk concepts provide a means of optimizing maintenance effort. However, in the face of poor data on reliability or condition, pragmatic approaches to risk-based prioritization are needed. One such approach, risk indexing, is considered in this paper. Background on the research is presented, including the application of risk-based inspection concepts within the water sector. The development of a risk indexing scheme is then investigated, drawing on two industry workshops in which the analytical hierarchy process was used to set relative weights. It is concluded that risk indexing provides the basis for a rational prioritization process in the absence of data on valve reliability or condition. - Highlights: ► Importance of valve inspections to water network reliability. ► Theoretical perspective of risk concepts that provide a means of optimizing inspection programs. ► Pragmatic approaches to prioritization in light of poor valve data. ► Development and assessment of a risk index scheme. ► Use of the analytical hierarchy process to set relative weights of risk factors.

  9. Visualization techniques (colposcopy, direct visual inspection, and spectroscopic and other visual methods). Summary of task force 7.

    Science.gov (United States)

    Wright, Thomas C; Menton, Michael; Myrtle, James F; Chow, Carl; Singer, Albert

    2002-01-01

    Visual screening techniques include both low-technology approaches, such as direct visual inspection (DVI), and high-technology approaches, such as those that utilize electrooptical detectors to identify cervical cancer precursors and invasive cervical cancer. Simple visual screening techniques, such as DVI, consist of washing the cervix with a solution of 5% acetic acid (e.g., vinegar) and then inspecting it using either the naked eye or with a low-power magnifying device to identify areas of acetowhitening, which frequently correspond to cervical squamous intraepithelial lesions (SILs). The simple visual screening methods are being evaluated as an alternative to cytology in low-resource settings where screening using cervical cytology is not feasible. Multiple studies have shown DVI to have sensitivity similar to that of cervical cytology for identifying women with high grade SIL but much lower specificity. The novel high-technology visual screening methods that utilize electrooptical sensors to identify cervical abnormalities are still in the developmental phases but offer considerable potential. PMID:12365209

  10. Evaluation of a new approach for the inspection of austenitic dissimilar welds using ultrasonic phased array techniques

    International Nuclear Information System (INIS)

    The inspection of the safe-end weld of pressurized water reactors is well known to be challenging. The fundamental obstacle to accurately characterising the defects of austenitic welds is the distortion of the sound field due to the anisotropic inhomogeneous material. This paper describes the evaluation of the next generation of ultrasonic procedures which use phased array techniques and models to account for the distortion of the sound field, such that the detection, positioning and sizing of defects is improved in comparison to current capabilities. Electron back scatter diffraction (EBSD) techniques were used to evaluate the texture of the weld and then the microstructural information was input to a model capable of propagating ultrasonic waves through the anisotropic inhomogeneous medium. With knowledge of the distortion, 2 strategies were developed for improving inspection: 1) adapting focal laws using time reversal concepts to improve sensitivity and 2) generating translation tables to correct positional and sizing errors of indications. This paper presents the final results of the project funded by the UK Technology Strategy Board. (authors)

  11. Two non-destructive neutron inspection techniques: prompt gamma-ray activation analysis and cold neutron tomography

    OpenAIRE

    Baechler, Sébastien; Dousse, Jean-Claude; Jolie, Jan

    2005-01-01

    Deux techniques d’inspection non-destructives utilisant des faisceaux de neutrons froids ont été développées à la source de neutrons SINQ de l’Institut Paul Scherrer : (1) l’analyse par activation neutronique prompte (PGAA) et (2) la tomographie neutronique. L’analyse par PGA (Prompt Gamma-ray Activation) est une méthode nucléaire qui permet de déterminer la concentration d’éléments présents dans un échantillon. Cette technique consiste à détecter les rayons gamma prompts émis par l’échantill...

  12. An Empirical Comparative Study of Checklist based and Ad Hoc Code Reading Techniques in a Distributed Groupware Environment

    CERN Document Server

    Akinola, Olalekan S

    2009-01-01

    Software inspection is a necessary and important tool for software quality assurance. Since it was introduced by Fagan at IBM in 1976, arguments exist as to which method should be adopted to carry out the exercise, whether it should be paper based or tool based, and what reading technique should be used on the inspection document. Extensive works have been done to determine the effectiveness of reviewers in paper based environment when using ad hoc and checklist reading techniques. In this work, we take the software inspection research further by examining whether there is going to be any significant difference in defect detection effectiveness of reviewers when they use either ad hoc or checklist reading techniques in a distributed groupware environment. Twenty final year undergraduate students of computer science, divided into ad hoc and checklist reviewers groups of ten members each were employed to inspect a medium sized java code synchronously on groupware deployed on the Internet. The data obtained were...

  13. The API methodology for risk-based inspection (RBI) analysis for the petroleum and petrochemical industry

    International Nuclear Information System (INIS)

    Twenty-one petroleum and petrochemical companies are currently sponsoring a project within the American Petroleum Institute (API) to develop risk-based inspection (RBI) methodology for application in the refining and petrochemical industry. This paper describes that particular RBI methodology and provides a summary of the three levels of RBI analysis developed by the project. Also included is a review of the first pilot project to validate the methodology by applying RBI to several existing refining units. The failure for pressure equipment in a process unit can have several undesirable effects. For the purpose of RBI analysis, the API RBI program categorizes these effects into four basic risk outcomes: flammable events, toxic releases, major environmental damage, and business interruption losses. API RBI is a strategic process, both qualitative and quantitative, for understanding and reducing these risks associated with operating pressure equipment. This paper will show how API RBI assesses the potential consequences of a failure of the pressure boundary, as well as assessing the likelihood (probability) of failure. Risk-based inspection also prioritizes risk levels in a systematic manner so that the owner-user can then plan an inspection program that focuses more resources on the higher risk equipment; while possibly saving inspection resources that are not doing an effective job of reducing risk. At the same time, if consequence of failure is a significant driving force for high risk equipment items, plant management also has the option of applying consequence mitigation steps to minimize the impact of a hazardous release, should one occur. The target audience for this paper is engineers, inspectors, and managers who want to understand what API Risk-Based Inspection is all about, what are the benefits and limitations of RBI, and how inspection practices can be changed to reduce risks and/or save costs without impacting safety risk. (Author)

  14. Automatic Inspection and Processing of Accessory Based on Vision Stitching and Spectral Illumination

    Directory of Open Access Journals (Sweden)

    Wen-Yang Chang

    2014-08-01

    Full Text Available The study investigates automatic inspection and processing of the stem accessories based on vision stitching and spectral illumination. The vision stitching mainly involves algorithms of white balance, scale-invariant feature transforms (SIFT and roundness for whole image of automatic accessory inspection. The illumination intensities, angles, and spectral analyses of light sources are analyzed for image optimal inspections. The unrealistic color casts of feature inspection is removed using a white balance algorithm for global automatic adjustment. The SIFT is used to extract and detect the image features for big image stitching. The Hough transform is used to detect the parameters of a circle for roundness of the bicycle accessories. The feature inspections of a stem contain geometry size, roundness, and image stitching. Results showed that maximum errors of 0°, 10°, 30°, and 50° degree for the spectral illumination of white light LED arrays with differential shift displacements are 4.4, 4.2, 6.8, and 3.5 %, respectively. The deviation error of image stitching for the stem accessory in x and y coordinates are 2 pixels. The SIFT and RANSAC enable to transform the stem image into local feature coordinates.

  15. BONDING OF MINIATURE PARTS WITH ADHESIVES AND VISION BASED PROCEDURE INSPECTION

    Institute of Scientific and Technical Information of China (English)

    Wang Xiaodong; Jürgen Hesselbach

    2004-01-01

    Bonding with adhesives is an important technique for building up hybrid microsystems.Some adhesives are tested with capillary dispensing system for microassembly,and volume of droplets less than 10 nl with good repeatability can be acquired.1-part UV curing adhesive hardens rapidly and is suitable for bonding of transparent microparts.Light-activated adhesive starts the curing process in an adjustable short period of time after the radiation of visible light,and thus suits bonding of non-transparent microparts.A method is proposed for bonding the guides of a miniature linear motor being developed by collaborate research center 516 (SFB516) in Germany.With the method high assembly accuracy in the vertical direction can be guaranteed.By making small grooves on the stator for containing adhesive,the deterioration of the accuracy due to the thickness of adhesive layer can be avoided.The criteria on deciding the size of the groove are given and analyzed.Vision based inspection method is introduced for automatic assembly of the guides.The dispensing volume and position of dispensed adhesive droplets can be detected for ensuring the bonding quality.

  16. GIS-based automated management of highway surface crack inspection system

    Science.gov (United States)

    Chung, Hung-Chi; Shinozuka, Masanobu; Soeller, Tony; Girardello, Roberto

    2004-07-01

    An automated in-situ road surface distress surveying and management system, AMPIS, has been developed on the basis of video images within the framework of GIS software. Video image processing techniques are introduced to acquire, process and analyze the road surface images obtained from a moving vehicle. ArcGIS platform is used to integrate the routines of image processing and spatial analysis in handling the full-scale metropolitan highway surface distress detection and data fusion/management. This makes it possible to present user-friendly interfaces in GIS and to provide efficient visualizations of surveyed results not only for the use of transportation engineers to manage road surveying documentations, data acquisition, analysis and management, but also for financial officials to plan maintenance and repair programs and further evaluate the socio-economic impacts of highway degradation and deterioration. A review performed in this study on fundamental principle of Pavement Management System (PMS) and its implementation indicates that the proposed approach of using GIS concept and its tools for PMS application will reshape PMS into a new information technology-based system that can provide convenient and efficient pavement inspection and management.

  17. Generative inspection process planner for integrated production

    Energy Technology Data Exchange (ETDEWEB)

    Brown, C.W. (Allied-Signal Aerospace Co., Kansas City, MO (USA). Kansas City Div.); Gyorog, D.A. (Kansas Univ., Lawrence, KS (USA). Dept. of Mechanical Engineering)

    1990-04-01

    This work describes the design prototype development of a generative process planning system for dimensional inspection. The system, IPPEX (Inspection Process Planning EXpert), is a rule-based expert system for integrated production. Using as advanced product modeler, relational databases, and artificial intelligence techniques, IPPEX generates the process plan and part program for the dimensional inspection of products using CMMs. Through an application interface, the IPPEX system software accesses product definition from the product modeler. The modeler is a solid geometric modeler coupled with a dimension and tolerance modeler. Resource data regarding the machines, probes, and fixtures are queried from databases. IPPEX represents inspection process knowledge as production rules and incorporates an embedded inference engine to perform decision making. The IPPEX system, its functional architecture, system architecture, system approach, product modeling environment, inspection features, inspection knowledge, hierarchical planning strategy, user interface formats, and other fundamental issues related to inspection planning and part programming for CMMs are described. 27 refs., 16 figs., 4 tabs.

  18. Magnetic Flux Leakage Sensing-Based Steel Cable NDE Technique

    Directory of Open Access Journals (Sweden)

    Seunghee Park

    2014-01-01

    Full Text Available Nondestructive evaluation (NDE of steel cables in long span bridges is necessary to prevent structural failure. Thus, an automated cable monitoring system is proposed that uses a suitable NDE technique and a cable-climbing robot. A magnetic flux leakage- (MFL- based inspection system was applied to monitor the condition of cables. This inspection system measures magnetic flux to detect the local faults (LF of steel cable. To verify the feasibility of the proposed damage detection technique, an 8-channel MFL sensor head prototype was designed and fabricated. A steel cable bunch specimen with several types of damage was fabricated and scanned by the MFL sensor head to measure the magnetic flux density of the specimen. To interpret the condition of the steel cable, magnetic flux signals were used to determine the locations of the flaws and the levels of damage. Measured signals from the damaged specimen were compared with thresholds that were set for objective decision-making. In addition, the measured magnetic flux signals were visualized as a 3D MFL map for intuitive cable monitoring. Finally, the results were compared with information on actual inflicted damages, to confirm the accuracy and effectiveness of the proposed cable monitoring method.

  19. Innovative Ultrasonic Techniques for Inspection and Monitoring of Large Concrete Structures

    OpenAIRE

    Niederleithinger E.; Wiggenhauser H.

    2013-01-01

    Ultrasonic echo and transmission techniques are used in civil engineering on a regular basis. New sensors and data processing techniques have lead to many new applications in the structural investigation as well as quality control. But concrete structures in the nuclear sector have special features and parameters, which pose problems for the methods and instrumentation currently available, e.g. extreme thickness, dense reinforcement, steel liners or special materials. Several innovative ultra...

  20. Mobile robot teleoperation system for plant inspection based on collecting and utilizing environment data

    International Nuclear Information System (INIS)

    This paper describes about development of a mobile robot teleoperation system for plant inspection. In our system, the robot is an agent for collecting the environment data and is also teleoperated by the operator utilizing such accumulated environment data which is displayed on the operation interface. The robot equips many sensors for detecting the state of the robot and the environment. Such redundant sensory system can be also utilized to collect the working environment data on-site while the robot is patrolling. Here, proposed system introduces the framework of collecting and utilizing environment data for adaptive plant inspection using the teleoperated robot. A view simulator is primarily aiming to facilitate evaluation of the visual sensors and algorithms and is also extended as the Environment Server, which is the core technology of the digital maintenance field for the plant inspection. In order to construct detailed seamless digital maintenance field mobile robotic technology is utilized to supply environment data to the server. The sensory system on the robot collect the environment data on-site and such collected data is uploaded to the Environment Server for compiling accurate digital environment data base. The robot operator also can utilize accumulated environment data by referring to the Environment Server. In this paper, we explain the concept of our teleoperation system based on collecting and utilizing environment data. Using developed system, inspection patrol experiments were attempted in the plant mock-up. Experimental results are shown by using an omnidirectional mobile robot with sensory system and the Environment Server. (author)

  1. A new track inspection car based on a laser camera system

    Institute of Scientific and Technical Information of China (English)

    Shengwei Ren; Shiping Gu; Guiyang Xu; Zhan Gao; Qibo Feng

    2011-01-01

    @@ We develop and build a new type of inspection car.A beam that is not rigidly connected to the train axle boxes and can absorb the vibration and impact caused by the high speed train is used, and a laser-camera measurement system based on the machine vision method is adopted.This method projects structural light onto the track and measures gauge and longitudinal irregularity.The measurement principle and model are discussed.Through numerous practical experiments, the rebuilt car is found to considerably eliminate the measurement errors caused by vibration and impact, thereby increasing measurement stability under high speeds.This new kind of inspection cars have been used in several Chinese administration bureaus.%We develop and build a new type of inspection car. A beam that is not rigidly connected to the train axle boxes and can absorb the vibration and impact caused by the high speed train is used, and a laser-camera measurement system based on the machine vision method is adopted. This method projects structural light onto the track and measures gauge and longitudinal irregularity. The measurement principle and model are discussed. Through numerous practical experiments, the rebuilt car is found to considerably eliminate the measurement errors caused by vibration and impact, thereby increasing measurement stability under high speeds. This new kind of inspection cars have been used in several Chinese administration bureaus.

  2. Preliminary study on the development of an in-service inspection technique for graphite components in the HTTR

    International Nuclear Information System (INIS)

    Development of a nondestructive measuring method on a residual strain and/or stress accumulating in the graphite component is one of major research subjects in the HTTR. For the purpose of the development of the method deformation characteristic under a small magnitude of a pressure load was measured using graphite specimens on which several levels of residual strains were produced. The pressure load was applied using a microhardness testing machine. In the experiment indentation load to depth characteristic and a microhardness were measured as a function of the residual strain. In this paper we describe the deformation characteristic influenced by the residual strain, and discuss the applicability of the micro-indentation method to the estimation of the residual strain arising in graphite components as an inservice inspection technique. (author)

  3. Automatic classification and defect verification based on inspection technology with lithography simulation

    Science.gov (United States)

    Kato, Masaya; Inuzuka, Hideki; Kosuge, Takeshi; Yoshikawa, Shingo; Kanno, Kayoko; Imai, Hidemichi; Miyashita, Hiroyuki; Vacca, Anthony; Fiekowsky, Peter; Fiekowsky, Dan

    2015-10-01

    Even small defects on the main patterns can create killer defects on the wafer, whereas the same defect on or near the decorative patterns may be completely benign to the wafer functionality. This ambiguity often causes operators and engineers to put a mask "on hold" to be analyzed by an AIMS™ tool which slows the manufacturing time and increases mask cost. In order to streamline the process, mask shops need a reliable way to quickly identify the wafer impact of defects during mask inspection review reducing the number of defects requiring AIMS™ analysis. Source Mask Optimization (SMO) techniques are now common on sub 20nm node critical reticle patterns These techniques create complex reticle patterns which often makes it difficult for inspection tool operators to identify the desired wafer pattern from the surrounding nonprinting patterns in advanced masks such as SMO, Inverse Lithography Technology (ILT), Negative Tone Development (NTD). In this study, we have tested a system that generates aerial simulation images directly from the inspection tool images. The resulting defect dispositions from a program defect test mask along with numerous production mask defects have been compared to the dispositions attained from AIMS™ analysis. The results of our comparisons are presented, as well as the impact to mask shop productivity.

  4. Railroad inspection based on ACFM employing a non-uniform B-spline approach

    Science.gov (United States)

    Chacón Muñoz, J. M.; García Márquez, F. P.; Papaelias, M.

    2013-11-01

    The stresses sustained by rails have increased in recent years due to the use of higher train speeds and heavier axle loads. For this reason surface and near-surface defects generate by Rolling Contact Fatigue (RCF) have become particularly significant as they can cause unexpected structural failure of the rail, resulting in severe derailments. The accident that took place in Hatfield, UK (2000), is an example of a derailment caused by the structural failure of a rail section due to RCF. Early detection of RCF rail defects is therefore of paramount importance to the rail industry. The performance of existing ultrasonic and magnetic flux leakage techniques in detecting rail surface-breaking defects, such as head checks and gauge corner cracking, is inadequate during high-speed inspection, while eddy current sensors suffer from lift-off effects. The results obtained through rail inspection experiments under simulated conditions using Alternating Current Field Measurement (ACFM) probes, suggest that this technique can be applied for the accurate and reliable detection of surface-breaking defects at high inspection speeds. This paper presents the B-Spline approach used for the accurate filtering the noise of the raw ACFM signal obtained during high speed tests to improve the reliability of the measurements. A non-uniform B-spline approximation is employed to calculate the exact positions and the dimensions of the defects. This method generates a smooth approximation similar to the ACFM dataset points related to the rail surface-breaking defect.

  5. Reactive underwater object inspection based on artificial electric sense.

    Science.gov (United States)

    Lebastard, Vincent; Boyer, Frédéric; Lanneau, Sylvain

    2016-01-01

    Weakly electric fish can perform complex cognitive tasks based on extracting information from blurry electric images projected from their immediate environment onto their electro-sensitive skin. In particular they can be trained to recognize the intrinsic properties of objects such as their shape, size and electric nature. They do this by means of novel perceptual strategies that exploit the relations between the physics of a self-generated electric field, their body morphology and the ability to perform specific movement termed probing motor acts (PMAs). In this article we artificially reproduce and combine these PMAs to build an autonomous control strategy that allows an artificial electric sensor to find electrically contrasted objects, and to orbit around them based on a minimum set of measurements and simple reactive feedback control laws of the probe's motion. The approach does not require any simulation models and could be implemented on an autonomous underwater vehicle (AUV) equipped with artificial electric sense. The AUV has only to satisfy certain simple geometric properties, such as bi-laterally (left/right) symmetrical electrodes and possess a reasonably high aspect (length/width) ratio. PMID:27458187

  6. Single Mode Guided Wave Technique For Pipe Inspection Using Laser Ultrasound

    International Nuclear Information System (INIS)

    The laser ultrasonic technique has been considered as a useful non-contact method to generate the ultrasonic guided wave in pipe. In practical applications of the guided wave technique, however, it is very important, though often difficult, to identify propagating modes. In this paper, we propose a wavelength-matched method using the ring-arrayed laser illumination that enables to generate only the specific longitudinal mode of which wavelength is determined by the array pitch. The effect of ring-arrayed illumination is uniformly launching the wavelength-matched guided wave along the circumferential direction. In this paper, experimental system is constructed, and pipe specimens are tested. The detector is the air-coupled transducer that is able to detect only a single mode by tuning its detection angle. Experimental results show that the predicted mode is clearly generated and detected. The proposed technique is fully non-contact, and it also has the advantage of greatly enhanced mode selectivity.

  7. Opportunistic condition-based maintenance and aperiodic inspections for a two-unit series system

    OpenAIRE

    Olde Keizer, Minou C.A.; Ruud H. Teunter

    2014-01-01

    Condition-Based Maintenance (CBM) intends to perform maintenance right before a failure occurs by estimating the pending moment of failure based on monitoring a certain condition, such as vibration or temperature. This paper considers a two-unit series system with economic dependencies. The aperiodic inspection moments are optimized simultaneously with the critical levels at which maintenance is performed in order to minimize cost and/or maximize availability. For this purpose, a stochastic m...

  8. A pilot application of risk-based methods to establish in-service inspection priorities for nuclear components at Surry Unit 1 Nuclear Power Station

    International Nuclear Information System (INIS)

    As part of the Nondestructive Evaluation Reliability Program sponsored by the US Nuclear Regulatory Commission, the Pacific Northwest Laboratory is developing a method that uses risk-based approaches to establish in-service inspection plans for nuclear power plant components. This method uses probabilistic risk assessment (PRA) results and Failure Modes and Effects Analysis (FEMA) techniques to identify and prioritize the most risk-important systems and components for inspection. The Surry Nuclear Power Station Unit 1 was selected for pilot applications of this method. The specific systems addressed in this report are the reactor pressure vessel, the reactor coolant, the low-pressure injection, and the auxiliary feedwater. The results provide a risk-based ranking of components within these systems and relate the target risk to target failure probability values for individual components. These results will be used to guide the development of improved inspection plans for nuclear power plants. To develop inspection plans, the acceptable level of risk from structural failure for important systems and components will be apportioned as a small fraction (i.e., 5%) of the total PRA-estimated risk for core damage. This process will determine target (acceptable) risk and target failure probability values for individual components. Inspection requirements will be set at levels to assure that acceptable failure probabilistics are maintained

  9. A pilot application of risk-based methods to establish in-service inspection priorities for nuclear components at Surry Unit 1 Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    Vo, T.; Gore, B.; Simonen, F.; Doctor, S. [Pacific Northwest Lab., Richland, WA (United States)

    1994-08-01

    As part of the Nondestructive Evaluation Reliability Program sponsored by the US Nuclear Regulatory Commission, the Pacific Northwest Laboratory is developing a method that uses risk-based approaches to establish in-service inspection plans for nuclear power plant components. This method uses probabilistic risk assessment (PRA) results and Failure Modes and Effects Analysis (FEMA) techniques to identify and prioritize the most risk-important systems and components for inspection. The Surry Nuclear Power Station Unit 1 was selected for pilot applications of this method. The specific systems addressed in this report are the reactor pressure vessel, the reactor coolant, the low-pressure injection, and the auxiliary feedwater. The results provide a risk-based ranking of components within these systems and relate the target risk to target failure probability values for individual components. These results will be used to guide the development of improved inspection plans for nuclear power plants. To develop inspection plans, the acceptable level of risk from structural failure for important systems and components will be apportioned as a small fraction (i.e., 5%) of the total PRA-estimated risk for core damage. This process will determine target (acceptable) risk and target failure probability values for individual components. Inspection requirements will be set at levels to assure that acceptable failure probabilistics are maintained.

  10. PWR nozzle 'crotch corner' inspection: an effective additional ultrasonic technique for radial cracks

    International Nuclear Information System (INIS)

    An ultrasonic non-destructive technique for testing the integrity of the nozzle crotch corner of a PWR pressure vessel is described which uses two angled probes to detect the specular reflection from one probe to the other via a crack lying in the important radial plane of the nozzle. (U.K.)

  11. Development of advanced techniques for life management and inspection of advanced heavy water reactor (AWHR) coolant channel components

    International Nuclear Information System (INIS)

    Operating life of pressure tubes of Pressurized Heavy Water Reactor (PHWR) is limited due to the presence of various issues associated with the material like hydrogen pick up, delayed hydride cracking, axial elongation and increase in diameter due to irradiation creep and growth. Periodic monitoring of the health of the pressure tube under in-situ conditions is essential to ensure the safe operation of the reactor. New designs of reactor call for innovative design philosophy, modification in fabrication route of pressure tube, development of reactor specific tools, both analytical and hardware for assessing the fitness for service of the pressure tube. Feedback from existing reactors has enhanced the understanding about life limiting parameters. This paper gives an insight into the life limiting issues associated with pressure tube and the efforts pursued for development of life management techniques for coolant channel of Advanced Heavy Water Reactor (AHWR) designed in India. The tools and techniques for in-situ property/hydrogen measurement, pulsed eddy current technique for zirconium alloy in-homogeneity characterization, horizontal shear wave EMAT system for dissimilar metal weld inspection, sliver sampling of vertical channel etc. are elaborated in the paper. (author)

  12. Reliability-Based Design and Planning of Inspection and Monitoring of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Marquez-Dominguez, Sergio

    and offshore wind turbine foundations with the aim of improving the design, decreasing structural costs and increasing benefits. Recently, wind energy technology has started to adopt risk and reliability based inspection planning (RBI) as a methodology based on Bayesian decision theories together......Maintaining and developing a sustainable wind industry is the main motivation of this PhD thesis entitled “Reliability-based design and planning of inspection and monitoring of offshore wind turbines”. In this thesis, statistical methods and probability theory are important mathematical tools used...... produced by the natural phenomena, i.e. wind and waves. This load interaction has an important influence on the dynamical behaviour as well as on the fatigue damage of the wind turbine structure, influencing its reliability and stability. In summation, wind, currents and sea loads can be considered...

  13. A Multi-Objective Genetic Algorithm for determining efficient Risk-Based Inspection programs

    International Nuclear Information System (INIS)

    This paper proposes a coupling between Risk-Based Inspection (RBI) methodology and Multi-Objective Genetic Algorithm (MOGA) for defining efficient inspection programs in terms of inspection costs and risk level, which also comply with restrictions imposed by international standards and/or local government regulations. The proposed RBI+MOGA approach has the following advantages: (i) a user-defined risk target is not required; (ii) it is not necessary to estimate the consequences of failures; (iii) the inspection expenditures become more manageable, which allows assessing the impact of prevention investments on the risk level; (iv) the proposed framework directly provides, as part of the solution, the information on how the inspection budget should be efficiently spent. Then, genetic operators are tailored for solving this problem given the huge size of the search space. The ability of the proposed RBI+MOGA in providing efficient solutions is evaluated by means of two examples, one of them involving an oil and gas separator vessel subject to internal and external corrosion that cause thinning. The obtained results indicate that the proposed genetic operators significantly reduce the search space to be explored and RBI+MOGA is a valuable method to support decisions concerning the mechanical integrity of plant equipment. - Highlights: • This paper proposes an original RBI multi-objective-based framework. • The exhaustive evaluation of these feasible programs is impossible in practice. • Thus, the effort to accomplish the analysis is fairly reduced. • Tool to support efficient decisions related to mechanical integrity of equipment

  14. Development of fluorescence based handheld imaging devices for food safety inspection

    Science.gov (United States)

    Lee, Hoyoung; Kim, Moon S.; Chao, Kuanglin; Lefcourt, Alan M.; Chan, Diane E.

    2013-05-01

    For sanitation inspection in food processing environment, fluorescence imaging can be a very useful method because many organic materials reveal unique fluorescence emissions when excited by UV or violet radiation. Although some fluorescence-based automated inspection instrumentation has been developed for food products, there remains a need for devices that can assist on-site inspectors performing visual sanitation inspection of the surfaces of food processing/handling equipment. This paper reports the development of an inexpensive handheld imaging device designed to visualize fluorescence emissions and intended to help detect the presence of fecal contaminants, organic residues, and bacterial biofilms at multispectral fluorescence emission bands. The device consists of a miniature camera, multispectral (interference) filters, and high power LED illumination. With WiFi communication, live inspection images from the device can be displayed on smartphone or tablet devices. This imaging device could be a useful tool for assessing the effectiveness of sanitation procedures and for helping processors to minimize food safety risks or determine potential problem areas. This paper presents the design and development including evaluation and optimization of the hardware components of the imaging devices.

  15. Advances based on digital technology named TEDDY+ for inspection of eddy current

    International Nuclear Information System (INIS)

    As a result of the recent developing line of eddy current data acquisition system a new product based on digital technology named TEDDY+, comes to the market. With only 4 kg of weight constitutes a great advance with regards to other equipment's available in the market. These advances, have enabled, among others, to increase considerably the signal to noise (S/N) ratio, avoid typical saturation problems in the eddy current signal, increase the inspection speed, eliminate the reference probe, detect the air/tube signal in real time, and the possibility to integrate the tester inside a push puller thanks to its reduced size and to have integrated as part of the ET equipment the mechanical systems control board. Two product lines have been developed, one oriented to any market and application (nuclear market, industrial and aeronautical, chemical and petrochemical, etc) and other specially dedicated to the massive inspection of tubes, named TEDDY+SP (Suitcase Pusher). Both lines are prepared to use eddy current arrays which clearly constitute the future of the eddy current inspection systems. The new TEDDY+ line of products presented in this paper constitutes one of the most powerful and reliable existing in the market. These improvements and novelties place the new ET inspection system from Tecnatom as one of the most powerful and reliable in the market. (Author)

  16. A distant real-time radar NDE technique for the in-depth inspection of glass fiber reinforced polymer-retrofitted concrete columns

    Science.gov (United States)

    Yu, Tzu-Yang; Buyukozturk, Oral

    2008-03-01

    A novel real-time radar NDE technique for the in-depth inspection of glass fiber reinforced polymer (GFRP)-retrofitted concrete columns is proposed. In this technique, continuous wave radar signals are transmitted in the far-field region (distant inspection), and reflected signals are collected by the same signal transmitter. Collected radar signals are processed by tomographic reconstruction methods for real-time image reconstruction. In-depth condition in the near-surface region of GFRP-concrete systems is revealed and evaluated by reconstructed images.

  17. Isis: An expert system for risk-based inservice inspection assessment

    International Nuclear Information System (INIS)

    The ASME Section XI Working Group on Implementation of Risk-Based (RB) Examination produced a code case to define risk-based selection rules that could be used for In-Service Inspection (ISI) of Class 1, 2 and 3 piping. To provide guidelines for practical implementation of the code case, EPRI sponsored work to develop evaluation procedures and criteria. The approach focuses inspections on locations which are selected based upon an explicit consideration of experienced degradation mechanisms and potential consequences. Software has been developed to execute and document this approach. Data and expert system modules address system operating characteristics, design attributes, the potential for damage mechanisms and the impact of component failures (i.e., loss of pressure boundary integrity). These modules are integrated in a stand alone software package. In addition, because the system is microcomputer based, the software is not cumbersome or costly to deploy. The goal of this effort was to develop a tool that will accomplish two tasks. That is, (1) Reduce the cost of the Risk Based Inservice Inspection (RBISI) evaluation effort by increasing the productivity of the BISI analyst, and (2) Provide a structured analytical and documentation package that lends itself to increases in consistency within an individual plant application, as well as across the industry

  18. Reliability-Based Planning of Inspection, Operation and Maintenance for Offshore Oil & Gas Structures and Wind Turbines

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    Reliability-based cost-optimal planning of inspection, maintenance and operation has many applications. In this paper applications for planning of inspections for oil & gas jacket structures and of operation and maintenance of offshore wind turbines are described and illustrated by examples....

  19. Application of EPRI risk-based inservice inspection procedure to combustion engineering design of nuclear power plant

    International Nuclear Information System (INIS)

    The EPRI developed risk-based inservice inspection procedure is used to select the elements for inservice inspection on a section of the high pressure safety injection system of the Entergy Operations ANO2 nuclear plant. This plant is the pilot plant in a six utility-eleven plant EPRI tailored collaboration program to apply the general EPRI procedures to Combustion Engineering NSSS designs. The procedure results in a reduction of candidate inspection locations from 14, based on current ASME Section XI rules for B-J welds to 3, based on the risk-based selection criteria

  20. The Liquisolid Technique: Based Drug Delivery System

    OpenAIRE

    Izhar Ahmed Syed; E. Pavani

    2012-01-01

    The “Liquisolid” technique is a novel and capable addition towards such an aims for solubility enhancement and dissolution improvement, thereby it increases the bioavailability. It contains liquid medications in powdered form. This technique is an efficient method for formulating water insoluble and water soluble drugs. This technique is based upon the admixture of drug loaded solutions with appropriate carrier and coating materials. The use of non-volatile solvent causes improved wettability...

  1. Presence and numbers of Campylobacter, Escherichia coli and Salmonella determined in boiler carcass rinses from United States processing plants in the hazard analysis and critical control point-based inspection models project

    Science.gov (United States)

    In 1999, the USDA-Food Safety Inspection Service introduced an inspection system called The HACCP-Based Inspection Models Project (HIMP). HIMP varies from traditional inspection in that more emphasis is placed on system inspection and verification. Each carcass is still visually inspected but some...

  2. Inspection-based, Automatic Support for Obtaining Usable Web Sites for Vision Impaired Users

    OpenAIRE

    Correani, Francesco; Leporini, Barbara; Patern?, Fabio

    2004-01-01

    The aim of this work is to provide designers and developers of Web applications with support to obtain systems that are usable for vision-impaired users. To this end, we have defined a number of design criteria to improve Web site navigation through screen readers or other similar devices. A navigation test by blind and vision-impaired subjects showed that our criteria improved Web site usability both qualitatively and quantitatively. An inspection-based tool has been developed to ease applic...

  3. The Theory of Theft: An Inspection Game Model of the Stolen Base Play in Baseball

    OpenAIRE

    Theodore L. Turocy

    2004-01-01

    This paper applies the theory of equilibrium in mixed strategies in an inspection game model to describe the strategic interaction in the stolen base play in baseball. A parsimonious simultaneous-move game model offers predictions about how the observable conduct of the teams on offense and defense responds as the characteristics of the players involved change. The theory organizes observations from play-by-play data from Major League Baseball, where highly-motivated, experienced professional...

  4. Vibration measurement-based simple technique for damage detection of truss bridges: A case study

    Directory of Open Access Journals (Sweden)

    Sudath C. Siriwardane

    2015-10-01

    Full Text Available The bridges experience increasing traffic volume and weight, deteriorating of components and large number of stress cycles. Therefore, assessment of the current condition of steel railway bridges becomes necessary. Most of the commonly available approaches for structural health monitoring are based on visual inspection and non-destructive testing methods. The visual inspection is unreliable as those depend on uncertainty behind inspectors and their experience. Also, the non-destructive testing methods are found to be expensive. Therefore, recent researches have noticed that dynamic modal parameters or vibration measurement-based structural health monitoring methods are economical and may also provide more realistic predictions to damage state of civil infrastructure. Therefore this paper proposes a simple technique to locate the damage region of railway truss bridges based on measured modal parameters. The technique is discussed with a case study. Initially paper describes the details of considered railway bridge. Then observations of visual inspection, material testing and in situ load testing are discussed under separate sections. Development of validated finite element model of the considered bridge is comprehensively discussed. Hence, variations of modal parameters versus position of the damage are plotted. These plots are considered as the main reference for locating the damage of the railway bridge in future periodical inspection by comparing the measured corresponding modal parameters. Finally the procedure of periodical vibration measurement and damage locating technique are clearly illustrated.

  5. US DOE-AECL cooperative program for development of high-level radioactive waste container fabrication, closure, and inspection techniques

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) and Atomic Energy of Canada Limited (AECL) plan to initiate a cooperative research program on development of manufacturing processes for high-level radioactive waste containers. This joint program will benefit both countries in the development of processes for the fabrication, final closure in a hot-cell, and certification of the containers. Program activity objectives can be summarized as follows: to support the selection of suitable container fabrication, final closure, and inspection techniques for the candidate materials and container designs that are under development or are being considered in the US and Canadian repository programs; and to investigate these techniques for alternate materials and/or container designs, to be determined in future optimization studies relating to long-term performance of the waste packages. The program participants will carry out this work in a conditional phased approach, and the scope of work for subsequent years will evolve subject to developments in earlier years. The overall term of this cooperative program is planned to run roughly three years. 5 refs., 2 tabs

  6. Automated Visual Inspection: Position Identification of Object for Industrial Robot Application based on Color and Shape

    Directory of Open Access Journals (Sweden)

    Muralindran Mariappan

    2016-01-01

    Full Text Available Inspection task is traditionally carried out by human. However, Automated Visual Inspection (AVI has gradually become more popular than human inspection due to the advantageous in the aspect of high precision and short processing time. Therefore, this paper proposed a system which identifies the object’s position for industrial robot based on colors and shapes where, red, green, blue and circle, square, triangle are recognizable. The proposed system is capable to identify the object’s position in three modes, either based on color, shape or both color and shape of the desired objects. During the image processing, RGB color space is utilized by the proposed system while winner take all approach is used to classify the color of the object through the evaluation of the pixel’s intensity value of the R, G and B channel. Meanwhile, the shapes and position of the objects are determined based on the compactness and the centroid of the region respectively. Camera settings, such as brightness, contrast and exposure is another important factor which can affect the performance of the proposed system. Lastly, a Graphical User Interface was developed. The experimental result shows that the developed system is highly efficient when implemented in the selected database.

  7. Development of ultrasonic testing DSP inspection technique for class 1 system piping in nuclear power plants

    International Nuclear Information System (INIS)

    The purpose of this study is to explore the utilization of new constant-Q SSP in ultrasonic NDE. Various engineering problems are reviewed, and suggestions for implementation of the technique are provided. The filters of new Constant-Q SSP centered on frequency points, and normalized type of the filtered signals was not nromalized. The new Constant-Q SSP uses the frequency-dependant response of the interfering coherent noise produced by unresolvable scatters in the resolution range cell of a transducer. It is implemented by splitting the frequency spectrum of the received signal with gaussian bandpass filters. The principles of the SSP and the various optimization algorithms are recalled, and the conventional decomposition method for the SSP was presented

  8. Image Based Authentication Using Steganography Technique

    OpenAIRE

    Satish Kumar Sonker; Sanjeev Kumar; Amit Kumar; Dr. Pragya Singh

    2013-01-01

    In the world of Information Security we are generally using Traditional (Text based) or multi factor Authentication Approach. Through which we are facing a lot of problems and it’s also less secure too. In these types conventional method attacks like brute-force attack, Dictionary Attack etc., are possible. This paper proposes the Image Based Authentication Using Steganography Technique considering the advantage of steganography technique along with the image. Including steganography in image...

  9. Bridging of inspection with corrosion management

    International Nuclear Information System (INIS)

    Formerly, Inspection and Corrosion Engineers have less interaction and sharing of information to each other even they are working in the same plant or organization. Inspection finding either from visual inspection or NDT techniques rarely shared with corrosion engineers. Similarly corrosion engineers rarely discussed their corrosion prediction and potential damage mechanism with inspection engineers. A demanding request of more holistic plant safety and asset integrity promoted the introduction and implementation of Risk Based Inspection (RBI). RBI analysis demands the input mainly from both disciplines i.e. Inspection and Corrosion Engineers. Most of RBI methodologies are once-off analysis approach which also promoted once-off interaction between Inspection and Corrosion Engineers. PETRONAS has developed a methodology with supporting software, integrating both Inspection and Corrosion disciplines. PETRONAS Risk Based Inspection (PRBI) is intended to promote continuous integration of Inspection and Corrosion management of the plant through out the whole life cycle starting from the design stage to fabrication, operation and decommissions stage. (author)

  10. The Potential of Acousto-Ultrasonic Techniques for Inspection of Baked Carbon Anodes

    Directory of Open Access Journals (Sweden)

    Moez Ben Boubaker

    2016-07-01

    Full Text Available High quality baked carbon anodes contribute to the optimal performance of aluminum reduction cells. However, the currently decreasing quality and increasing variability of anode raw materials (coke and pitch make it challenging to manufacture the anodes with consistent overall quality. Intercepting faulty anodes (e.g., presence of cracks and pores before they are set in reduction cells and deteriorate their performance is therefore important. This is a difficult task, even in modern and well-instrumented anode plants, because lab testing using core samples can only characterize a small proportion of the anode production due to the costly, time-consuming, and destructive nature of the analytical methods. In addition, these results are not necessarily representative of the whole anode block. The objective of this work is to develop a rapid and non-destructive method for quality control of baked anodes using acousto-ultrasonic (AU techniques. The acoustic responses of anode samples (sliced sections were analyzed using a combination of temporal features computed from AU signals and principal component analysis (PCA. The AU signals were found sensitive to pores and cracks and were able to discriminate the two types of defects. The results were validated qualitatively by submitting the samples to X-ray Computed Tomography (CT scan.

  11. A Longitudinal Mode Electromagnetic Acoustic Transducer (EMAT) Based on a Permanent Magnet Chain for Pipe Inspection.

    Science.gov (United States)

    Cong, Ming; Wu, Xinjun; Qian, Chunqiao

    2016-01-01

    A new electromagnetic acoustic transducer (EMAT) design, employing a special structure of the permanent magnet chain, is proposed to generate and receive longitudinal guided waves for pipe inspection based on the magnetostriction mechanism. Firstly, a quantitative analysis of the excitation forces shows the influence of the radial component can be ignored. Furthermore, as the axial component of the static magnetic field is dominant, a method of solenoid testing coils connected in series is adopted to increase the signal amplitude. Then, two EMAT configurations are developed to generate and receive the L(0,2) guided wave mode. The experimental results show the circumferential notch can be identified and located successfully. Finally, a detailed investigation of the performance of the proposed EMATs is given. Compared to the conventional EMAT configuration, the proposed configurations have the advantages of small volume, light weight, easy installation and portability, which is helpful to improve inspection efficiency. PMID:27213400

  12. Report on inspection of the performance based incentive program at the Richland Operations Office

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-10

    The Fiscal Year (FY) 1995 Performance Based Incentive (PBI) Program at the Department of Energy`s (DOE) Richland Operations Office (Richland) was initiated by Richland as one part of the broader DOE Contract Reform Initiative being implemented at the Hanford Site in FY 1995. This program was identified as an area of concern by the Office of Inspections as a result of previous inspection work. Specifically, during a limited review of the construction of an Effluent Treatment Facility at the Hanford Site, we were unable to identify any written policies describing PBI program controls or implementation procedures. We were told that Richland Operations Office Program Management personnel were not directly involved in the selection of the Effluent Treatment Facility project for the PBI Program, or in the determination that this particular PBI would be established with a potential fee of $1 million.

  13. An airport cargo inspection system based on X-ray and thermal neutron analysis (TNA)

    International Nuclear Information System (INIS)

    A cargo inspection system incorporating a high-resolution X-ray imaging system with a material-specific detection system based on Ancore Corporation's patented thermal neutron analysis (TNA) technology can detect bulk quantities of explosives and drugs concealed in trucks or cargo containers. The TNA process utilises a 252Cf neutron source surrounded by a moderator. The neutron interactions with the inspected object result in strong and unique gamma-ray signals from nitrogen, which is a key ingredient in modern high explosives, and from chlorinated drugs. The TNA computer analyses the gamma-ray signals and automatically determines the presence of explosives or drugs. The radiation source terms and shielding design of the facility are described. For the X-ray generator, the primary beam, leakage radiation, and scattered primary and leakage radiation were considered. For the TNA, the primary neutrons and tunnel scattered neutrons as well as the neutron-capture gamma rays were considered. (authors)

  14. Surface defect inspection of TFT-LCD panels based on 1D Fourier method

    Science.gov (United States)

    Zhang, Teng-da; Lu, Rong-sheng

    2016-01-01

    Flat panel displays have been used in a wide range of electronic devices. The defects on their surfaces are an important factor affecting the product quality. Automated optical inspection (AOI) method is an important and effective means to perform the surface defection inspection. In this paper, a kind of defect extraction algorithm based on one dimensional (1D) Fourier theory for the surface defect extraction with periodic texture background is introduced. In the algorithm, the scanned surface images are firstly transformed from time domain to frequency domain by 1D Fourier transform. The periodic texture background on the surface is then removed by using filtering methods in the frequency domain. Then, a dual-threshold statistical control method is applied to separate the defects from the surface background. Traditional 1D Fourier transform scheme for detecting ordinary defects is very effective; however, the method is not where the defect direction is close to horizontal in periodic texture background. In order to tackle the problem, a mean threshold method based on faultless image is put forward. It firstly calculates the upper and lower control limits of the every reconstructed line scanned image with faultless and then computes the averages of the upper and lower limits. The averages then act as the constant double thresholds to extract the defects. The experimental results of different defects show that the method developed in the paper is very effective for TFT-LCD panel surface defect inspection even in the circumstance that the defect directions are close to horizontal.

  15. Auxiliary feedwater system risk-based inspection guide for the Point Beach nuclear power plant

    International Nuclear Information System (INIS)

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Point Beach was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRS. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Point Beach plant

  16. Auxiliary feedwater system risk-based inspection guide for the Virgil C. Summer Nuclear Power Plant

    International Nuclear Information System (INIS)

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the emergency/auxiliary feedwater (EFW/AFW) system at press water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses costing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify genetic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Virgil C. Summer plant was selected as one m a series of plants for study. The product of this effort is a priority listing of AFW failures which have occurred at the plant and at other PWRS. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at Virgil C. Summer plant

  17. The Model Transformation-based Tool Building Techniques and Their Implementation

    OpenAIRE

    Edgars Rencis

    2012-01-01

    Abstract In Doctoral Thesis „The Model Transformation-based Tool Building Techniques and Their Implementation” a model transformation- and metamodel-based domainspecific tool building area is inspected paying the main attention to the problem of making the development and usage of such tools easier. The tool building platform GRAF is examined since it has been partly developed by the author. This platform is supplemented with several services alleviating both the development...

  18. Complete robotic inspection line using PC-based control, supervision and parameterization software

    OpenAIRE

    Norberto Pires, J.; Paulo, Sérgio

    2005-01-01

    Non-flat ceramic products, like toilets and bidets, are fully inspected at the end of the production process, to search for structural, surface and functional defects. Ceramic pieces are transported to the inspection lines assembled in pallets, carried by electro-mechanical fork-lifters or automatic guided vehicles. Pallets need to be disassembled, while feeding with the inspection lines where human operators execute the inspection tasks. Also, the pieces that pass inspection need to be palle...

  19. Review of P-scan computer-based ultrasonic inservice inspection system. Supplement 1

    International Nuclear Information System (INIS)

    This Supplement reviews the P-scan system, a computer-based ultrasonic system used for inservice inspection of piping and other components in nuclear power plants. The Supplement was prepared using the methodology described in detail in Appendix A of NUREG/CR-5985, and is based on one month of using the system in a laboratory. This Supplement describes and characterizes: computer system, ultrasonic components, and mechanical components; scanning, detection, digitizing, imaging, data interpretation, operator interaction, data handling, and record-keeping. It includes a general description, a review checklist, and detailed results of all tests performed

  20. The SAFT-UT (synthetic aperture focusing technique for ultrasonic testing) real-time inspection system: Operational principles and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Hall, T. E.; Reid, L. D.; Doctor, S. R.

    1988-06-01

    This document provides a technical description of the real-time imaging system developed for rapid flaw detection and characterization utilizing the synthetic aperture focusing technique for ultrasonic testing (SAFT-UT). The complete fieldable system has been designed to perform inservice inspection of light-water reactor components. Software was written on a DEC LSI 11/23 computer system to control data collection. The unprocessed data is transferred to a VAX 11/730 host computer to perform data processing and image display tasks. A parallel architecture peripheral to the host computer, referred to as the Real-Time SAFT Processor, rapidly performs the SAFT processing function. From the host's point of view, this device operates on the SAFT data in such a way that one may consider it to be a specialized or SAFT array processor. A guide to SAFT-UT theory and conventions is included, along with a detailed description of the operation of the software, how to install the software, and a detailed hardware description.

  1. Development of under-sodium three-dimensional visual inspection technique using matrix-arrayed ultrasonic transducer

    International Nuclear Information System (INIS)

    We have developed an advanced under-sodium ultrasonic visual inspection technique in order to observe in-vessel structures in a Fast Breeder Reactor (FBR) whose reactor vessel is filled with opaque liquid sodium. The final goal of this work is achievement of resolution equivalent to that of an image obtained by optical fiber scope. The under-sodium ultrasonic visualizing system consists of a matrix-arrayed transducer and a signal-processing device. The matrix-arrayed transducer, in which 36x36 piezoelectric elements are arranged with 5 mm interval and sealed by a thin metal diaphragm, can realize a 3-dimensional image with high resolution. Regarding signal processing, the 3-dimensional image synthetic processing and the cross correlation processing for the purpose of improving S/N ratio of ultrasonic echoes are implemented on a high-speed parallel processor. Under-sodium imaging test was carried out, and it was confirmed that a 3-dimensional image of the blind target, which was prepared without information beforehand, could be visualized clearly with less than 2.0 mm resolution under-sodium. (author)

  2. An Empirical Comparative Study of Checklist-based and Ad Hoc Code Reading Techniques in a Distributed Groupware Environment

    Directory of Open Access Journals (Sweden)

    Adenike O. Osofisan

    2009-09-01

    Full Text Available Software inspection is a necessary and important tool for software quality assurance. Since it was introduced by Fagan at IBM in 1976, arguments exist as to which method should be adopted to carry out the exercise, whether it should be paper-based or tool-based, and what reading technique should be used on the inspection document. Extensive works have been done to determine the effectiveness of reviewers in paper-based environment when using ad hoc and checklist reading techniques. In this work, we take the software inspection research further by examining whether there is going to be any significant difference in defect detection effectiveness of reviewers when they use either ad hoc or checklist reading techniques in a distributed groupware environment. Twenty final year undergraduate students of computer science, divided into ad hoc and checklist reviewers groups of ten members each were employed to inspect a medium-sized java code synchronously on groupware deployed on the Internet. The data obtained were subjected to tests of hypotheses using independent t-test and correlation coefficients. Results from the study indicate that there are no significant differences in the defect detection effectiveness, effort in terms of time taken in minutes and false positives reported by the reviewers using either ad hoc or checklist based reading techniques in the distributed groupware environment studied.Key words: Software Inspection, Ad hoc, Checklist, groupware.

  3. Vision-based inspection for periodic defects in steel wire rod production

    Science.gov (United States)

    Park, Changhyun; Choi, Seho; Won, Sangchul

    2010-01-01

    Defective rollers in rolling plants often create spatially periodic defects on the product surface. It is essential for operators to receive early warnings of such periodic defects and take appropriate action to avoid a large quantity of defective products. We present a robust and efficient real-time method for inspecting periodic defects in continuous steel wire rods. The proposed inspection method consists of two parts: (1) an algorithm for detecting all defect candidates and (2) an algorithm to detect periodicities in the detected defect candidates and to determine their periods. The first algorithm exploits the translation-invariant property of the Haar undecimated discrete wavelet transform to improve the signal-to-noise ratio of the surface image. The second algorithm is based on analysis of the frequency spectrum of defect candidate positions. It identifies periodicities of the defect candidates by finding repeating impulse-like spectra. The inspection system using the proposed method is applied to a real production line and detects periodic defects in real time and identifies their periodicities with high accuracy.

  4. A long standoff profilometer for surface inspection in adverse environments based on conoscopic holography

    Science.gov (United States)

    Enguita, Jose M.; Alvarez, Ignacio; Fraga, Cesar; Marina, Jorge; Fernandez, Yolanda; Sirat, Gabriel

    2005-06-01

    One of the more challenging applications of optical metrology is real-time dimensional control and surface inspection in industrial applications, where strong requirements of cost, setup and applicability in adverse environments, greatly limit the number of applicable technologies. This paper shows an optic profilometer developed specifically for this purpose. This device, based on Conoscopic holography, is able to obtain a distance profile of a target in a single-axis scan; works from long distances and still keeps good resolution with a very easy and reliable setup. The first part of the paper introduces the working principles of Conoscopic holography and shows the sensor set-up. Necessary algorithms for obtaining the distance information are presented and the whole process is illustrated with real captures of test objects. The second part focuses on a real example of this technology applied in an on-line inspection system in steel continuous casting funded by the European Committee for Steel and Carbon, and which is currently working in Aceralia LDA steelmaking factory in Asturias, Spain). The system is placed in the process line and performs on-line detection of surface defects over hot steel slabs from a distance of 1200 mm. 100% of the production can be inspected without interfering with the process and without adding any delay.

  5. Development of the repair technique using by the local polishing system with high quality optical inspection camera for the L-band superconducting rf cavity

    International Nuclear Information System (INIS)

    To develop cavity repair techniques is important for quality control of the superconducting rf cavity to get more better yield for high accelerating gradient. A high-quality optical inspection system with a high-resolution camera was developed as a tool of inspection of the cavities in 2008. It enables 2-D surface analysis on a defect of cavity inner surface by using striped illumination and image processing. For more detailed surface analysis, a replica technique was applied to cavity surface. By connecting defect information with quench location information, the cause of the performance limitation can be categorized by a geometrical defect or by issue of surface treatment and assembly work. By applying optical inspection at each step of the treatment, we can also obtain an information of defect appearance and its development. The cavities that quenched at low field by one or few geometrical defects can be improved by removing the defects at quench location. A local polishing system with a small grinding machine was developed for this purpose. This repair method was applied on the 9-cell cavities, and we succeeded to improve the cavity performance by the combination of local polishing and light electro-polish (EP). The method and results of the cavity inspection including the replica techniques and local polishing are presented in this paper. (author)

  6. Flow Modeling Based Wall Element Technique

    Directory of Open Access Journals (Sweden)

    Sabah Tamimi

    2012-08-01

    Full Text Available Two types of flow where examined, pressure and combination of pressure and Coquette flow of confined turbulent flow with a one equation model used to depict the turbulent viscosity of confined flow in a smooth straight channel when a finite element technique based on a zone close to a solid wall has been adopted for predicting the distribution of the pertinent variables in this zone and examined even with case when the near wall zone was extended away from the wall. The validation of imposed technique has been tested and well compared with other techniques.

  7. A Shape Based Image Search Technique

    Directory of Open Access Journals (Sweden)

    Aratrika Sarkar

    2014-08-01

    Full Text Available This paper describes an interactive application we have developed based on shaped-based image retrieval technique. The key concepts described in the project are, imatching of images based on contour matching; iimatching of images based on edge matching; iiimatching of images based on pixel matching of colours. Further, the application facilitates the matching of images invariant of transformations like i translation ; ii rotation; iii scaling. The key factor of the system is, the system shows the percentage unmatched of the image uploaded with respect to the images already existing in the database graphically, whereas, the integrity of the system lies on the unique matching techniques used for optimum result. This increases the accuracy of the system. For example, when a user uploads an image say, an image of a mango leaf, then the application shows all mango leaves present in the database as well other leaves matching the colour and shape of the mango leaf uploaded.

  8. Risk-based maintenance-Techniques and applications

    International Nuclear Information System (INIS)

    Plant and equipment, however well designed, will not remain safe or reliable if it is not maintained. The general objective of the maintenance process is to make use of the knowledge of failures and accidents to achieve the possible safety with the lowest possible cost. The concept of risk-based maintenance was developed to inspect the high-risk components usually with greater frequency and thoroughness and to maintain in a greater manner, to achieve tolerable risk criteria. Risk-based maintenance methodology provides a tool for maintenance planning and decision making to reduce the probability of failure of equipment and the consequences of failure. In this paper, the risk analysis and risk-based maintenance methodologies were identified and classified into suitable classes. The factors affecting the quality of risk analysis were identified and analyzed. The applications, input data and output data were studied to understand their functioning and efficiency. The review showed that there is no unique way to perform risk analysis and risk-based maintenance. The use of suitable techniques and methodologies, careful investigation during the risk analysis phase, and its detailed and structured results are necessary to make proper risk-based maintenance decisions

  9. Application of risk-based methods to inservice inspection of piping systems

    International Nuclear Information System (INIS)

    Research efforts have been underway in the American Society of Mechanical Engineers (ASME) and industry to define appropriate methods for the application of risk-based technology in the development of inservice inspection (ISI) programs for piping systems in nuclear power plants. This paper discusses a pilot application of these methods to the inservice inspection of piping systems of Northeast Utilities Millstone Unit 3 nuclear power station. This demonstration study, which has been sponsored by the Westinghouse Owners Group (WOG), applies probabilistic safety assessment (PSA) models that have already been developed to meet regulatory requirements for an individual plant examination (IPE). The approach calculates the relative importance for each component within the systems of interest. This risk-importance is based on the frequency of core damage resulting from the structural failure of the component. The process inductively determines the effects that such failures have on the desired operational characteristics of the system being analyzed. Structural reliability/risk assessment (SRRA) models based on probabilistic structural mechanics methods are used to estimate failure probabilities for important components. Locations within a system with varying failure probabilities can be defined to focus ISI resources. This paper will discuss the above process and results to show that application of risk-based methods in the development of ISI programs can potentially result in significant savings while maintaining a high level of safety

  10. Reliability-based design and planning of inspection and monitoring of offshore wind turbines

    DEFF Research Database (Denmark)

    Dominguez, Sergio Marquez

    When the wind is blowing fiercely, wind turbines must resist. Wind turbines have to withstand the rough environmental conditions in the most reliable manner and start to produce renewable energy when the wind becomes friendly again. Never give up ‘wind turbine’ face the winds and be proud of...... contributing as an energy sources. Reading this thesis, the reader will get the basic knowledge necessary for successful application of the main theories of structural reliability applied to both onshore and offshore wind turbine substructures considering building materials as steel and concrete. Additionally...... probability and statistics for application in structural reliability-based risk inspections....

  11. Evaluation of ray-based methods for the simulation of UT welds inspection

    International Nuclear Information System (INIS)

    The reliability of ray-based approaches for the simulation of inspection of austenitic or bimetallic welds is assessed. A first modeling approach consists in describing the weld as a set of several anisotropic homogeneous domains with a given grain orientation. In this case, the rays travel in straight lines inside each domain. A second modeling approach uses dynamic ray tracing, considering a smooth description of the crystallographic orientation. Simulation results using both approaches are presented, discussed and compared to finite elements results. (authors)

  12. Inspection And Adaptive Robot Applications Based On Three-Dimensional Vision Measurements

    Science.gov (United States)

    Schmidt, Richard Q.

    1985-01-01

    Several industrial applications have been implemented based on a 3-D vision sensor developed by Robotic Vision Systems, Inc. (RVSI). The sensor, known as the Robo Sensor, uses structured light and optical triangulation to obtain 3-D data in real time on surfaces within its field of view. This paper will describe the Robo Sensor vision system and some of the manufacturing tasks in which the sensors have been installed. The applications range from adaptively positioning welding robots for the General Motors car production to inspection of large propeller surfaces for the U.S. Navy. Extension of the technology to provide 3-D volumetric sensing is also presented.

  13. High Pressure Coolant Injection (HPCI) System Risk-Based Inspection Guide for Browns Ferry Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    Wong, S.; DiBiasio, A.; Gunther, W. [Brookhaven National Lab., Upton, NY (United States)

    1993-09-01

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A System Risk-Based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Browns Ferry Nuclear Power Plant, Units 1, 2 and 3. The role of. the HPCI system in mitigating accidents is discussed in this S-RIG, along with insights on identified risk-based failure modes which could prevent proper operation of the system. The S-RIG provides a review of industry-wide operating experience, including plant-specific illustrative examples to augment the PRA and operational considerations in identifying a catalogue of basic PRA failure modes for the HPCI system. It is designed to be used as a reference for routine inspections, self-initiated safety system functional inspections (SSFIs), and the evaluation of risk significance of component failures at the nuclear power plant.

  14. High Pressure Coolant Injection (HPCI) System Risk-Based Inspection Guide for Browns Ferry Nuclear Power Station

    International Nuclear Information System (INIS)

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A System Risk-Based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Browns Ferry Nuclear Power Plant, Units 1, 2 and 3. The role of. the HPCI system in mitigating accidents is discussed in this S-RIG, along with insights on identified risk-based failure modes which could prevent proper operation of the system. The S-RIG provides a review of industry-wide operating experience, including plant-specific illustrative examples to augment the PRA and operational considerations in identifying a catalogue of basic PRA failure modes for the HPCI system. It is designed to be used as a reference for routine inspections, self-initiated safety system functional inspections (SSFIs), and the evaluation of risk significance of component failures at the nuclear power plant

  15. Coplanarity inspection of BGA solder balls based on laser interference structure light

    Science.gov (United States)

    Wei, Zhe; Xiao, Zexin; Zhang, Xuefei; Zhou, Haiying

    2011-11-01

    Using laser interference structure light for profilometry is a rapid, non-contact, full-field profile and high accuracy measuring method.And it has been a promising technique in complicated geometrical shape measurement. In this paper, a fast and cost-effective measurement method of coplanarity inspection of ball grid array (BGA) solder balls is proposed. Laser interference structure light can be obtained by using the principle of shearing interferometry. The collimated and beam expanded laser produced interference fringe by the high reflection rate optical flat. After laser interference fringe project on the surface of object and the structured light would modulated. The light signal pass through the image optical grabber and captured by the CCD image sensor. The height of each point on object can be demodulated by the imaging processing software.This method to construct the measurement appliance for coplanarity inspection of ball grid array (BGA) chip solder ball. Experiments have shown that the coplanarity measurement of BGA solder balls is very efficient and effective with the measurement. The measurement accuracy achieve micrometer level. The processing time of the measurement accuracy is less than 3s on a personal computer. This measurement appliance could completely meet the demand of measure.

  16. The Application of Non-Destructive Techniques in the Quality Control Inspection and Testing of Fuel Materials for the Dragon Reactor Experiment

    International Nuclear Information System (INIS)

    The O.E.C.D. high temperature gas-cooled reactor experiment. Dragon, is graphite-moderated and helium-cooled and employs fission product-retaining fuel of the coated-particle type. The development and use of this new type of fuel have required the application of a variety of non-destructive techniques for quality control, inspection and testing. This paper describes certain of the methods which are employed in the inspection of fuel materials both in the development phase and subsequently in production. Physical methods of analysis are used for control of the chemical analysis of fuel cartridges and assessment of fuel contamination of fuel-particle coatings, and particular gamma spectrometric and alpha-scintillation counting techniques are described. The general quality of coated particles is assessed and metrology of coatings performed by means of micro-radiography with the X-ray projection microscope; the procedure is outlined and typical results are presented. Fuel cartridges which consist of fuel particles in a graphite matrix are inspected for homogeneity of fuel distribution and freedom from defects by fluoroscopy and panoramic slit-scanning radiography. Colour radiography is also employed to a limited extent and the various techniques are presented together with illustrative examples of the results obtained. The fuel elements are fabricated almost entirely from various grades of graphite, and eddy-current non-destructive testing techniques are being developed to permit inspection of raw materials and finished machined components for freedom from significant defects. A brief description of these techniques is given. (author)

  17. IMAGE ANALYSIS BASED ON EDGE DETECTION TECHNIQUES

    Institute of Scientific and Technical Information of China (English)

    纳瑟; 刘重庆

    2002-01-01

    A method that incorporates edge detection technique, Markov Random field (MRF), watershed segmentation and merging techniques was presented for performing image segmentation and edge detection tasks. It first applies edge detection technique to obtain a Difference In Strength (DIS) map. An initial segmented result is obtained based on K-means clustering technique and the minimum distance. Then the region process is modeled by MRF to obtain an image that contains different intensity regions. The gradient values are calculated and then the watershed technique is used. DIS calculation is used for each pixel to define all the edges (weak or strong) in the image. The DIS map is obtained. This help as priority knowledge to know the possibility of the region segmentation by the next step (MRF), which gives an image that has all the edges and regions information. In MRF model,gray level l, at pixel location i, in an image X, depends on the gray levels of neighboring pixels. The segmentation results are improved by using watershed algorithm. After all pixels of the segmented regions are processed, a map of primitive region with edges is generated. The edge map is obtained using a merge process based on averaged intensity mean values. A common edge detectors that work on (MRF) segmented image are used and the results are compared. The segmentation and edge detection result is one closed boundary per actual region in the image.

  18. Monte-Carlo simulations of neutron-induced activation in a Fast-Neutron and Gamma-Based Cargo Inspection System

    Science.gov (United States)

    Bromberger, B.; Bar, D.; Brandis, M.; Dangendorf, V.; Goldberg, M. B.; Kaufmann, F.; Mor, I.; Nolte, R.; Schmiedel, M.; Tittelmeier, K.; Vartsky, D.; Wershofen, H.

    2012-03-01

    An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. The induced activity was determined by analyzing the gamma spectra. Based on the calculated radioactive inventory in the container, the dose levels due to the induced gamma radiation were calculated at several distances from the container and in relevant time windows after the irradiation, in order to evaluate the radiation exposure of the cargo handling staff, air crew and passengers during flight. The possibility of remanent long-lived radioactive inventory after cargo is delivered to the client is also of concern and was evaluated.

  19. Rapid Tooling Technique Based on Stereolithograph Prototype

    Institute of Scientific and Technical Information of China (English)

    丁浩; 狄平; 顾伟生; 朱世根

    2001-01-01

    Rapid tooling technique based on the sterelithograph prototype is investigated. The epoxy tooling technological process was elucidated. It is analyzed in detail that the epoxy resin formula is easy to cast, curing process, and release agents. The transitional plaster model is also proposed. The mold to encrust mutual.inductors with epoxy and mold to inject plastic soapboxes was made with the technique The tooling needs very little time and cost, for the process is only to achieve the nice replica of the prototype. It is benefit for the trial and small batch of production.

  20. 农产品农药残留速测技术的应用探讨%Application of Instant Inspection Techniques of Pesticide Residues in Agricultural Products

    Institute of Scientific and Technical Information of China (English)

    王娇

    2012-01-01

    The application of instant inspection techniques in detecting pesticides residues in vegetables can effectively prevent poisonous vegetables into the market, creating positive social benefits. This article examines the necessity and feasibility in applying instant inspection techniques as well as its advantages and drawbacks in a bid to provide reference for its promotion and application.%应用农药残留速测技术检测蔬菜的农药残留,可有效的防止“毒菜”进入市场,具有良好的社会效益。分析应用农药残留速测技术的必要性和可行性,通过适用性试验,探讨此法的优点及存在的问题,为其推广应用提供参考。

  1. Studi Aplikasi Metode Risk Based Inspection (RBI Semi-Kuantitatif API 581 pada Production Separator

    Directory of Open Access Journals (Sweden)

    Moamar Al Qathafi

    2015-03-01

    Full Text Available Risk Based Inspection (RBI merupakan sebuah metode untuk merancang inspeksi dengan menggunakan dasar resiko yang dimiliki oleh alat pada unit kerja. Pada tugas akhir ini peralatan yang diteliti adalah Production Separator. Dimana production separator merupakan salah satu jenis pressure vessel. Pressure vessel adalah alat yang memiliki tekanan dan temperatur berbeda dengan kondisi lingkungan untuk menyesuaikan dengan fluida. Sebagaimana yang telah diketahui, bahwa setiap alat yang menggunakan tekanan dalam kerjanya diperlukan sebuah inspeksi untuk meyakinkan alat dapat berkerja secara baik. Hal ini dikarenakan jika terjadi kegagalan maka akibat yang ditimbulkan sangat besar baik pada manusia maupun lingkungan. Metode yang digunakan dalam tugas akhir ini adalah metode Risk Based Inspection Semi-Kuantitatif API 581, yang nantinya akan menghasilkan nilai resiko dan risk level dari alat. Hasil dari analisis menunjukkan bahwa terdapat 24 bagian memiliki tingkat resiko medium risk dan 4 bagian memiliki tingkat resiko medium high risk. Dengan mekanisme kerusakan thinning maka disarankan untuk melakukan inspeksi selanjutnya tidak melebihi setengah sisa umur pakai. Untuk metode inspeksi yang disarankan adalah visual examination dan ultrasonic test.

  2. Low-Cost Impact Detection and Location for Automated Inspections of 3D Metallic Based Structures

    Directory of Open Access Journals (Sweden)

    Carlos Morón

    2015-05-01

    Full Text Available This paper describes a new low-cost means to detect and locate mechanical impacts (collisions on a 3D metal-based structure. We employ the simple and reasonably hypothesis that the use of a homogeneous material will allow certain details of the impact to be automatically determined by measuring the time delays of acoustic wave propagation throughout the 3D structure. The location of strategic piezoelectric sensors on the structure and an electronic-computerized system has allowed us to determine the instant and position at which the impact is produced. The proposed automatic system allows us to fully integrate impact point detection and the task of inspecting the point or zone at which this impact occurs. What is more, the proposed method can be easily integrated into a robot-based inspection system capable of moving over 3D metallic structures, thus avoiding (or minimizing the need for direct human intervention. Experimental results are provided to show the effectiveness of the proposed approach.

  3. Characterization of spent fuel elements stored at IEA-R1 research reactor based on visual inspections and sipping tests

    International Nuclear Information System (INIS)

    Aluminum spent nuclear fuels are susceptible to corrosion attack, or mechanical damage from improper handling, while in pool reactor storage. Storage practices have been modified to reduce the potential for damage, based on recommendations presented at second WS on Spent Fuel Characterization, promoted by IAEA. In this work, we present the inspection program proposed to the IEA-R1 stored spent fuel elements, in order to provide information on the physical condition during the interim storage time under wet condition at the reactor pool. The inspection program is based on non-destructive tests results (visual inspection and sipping tests) already periodically performed to exam the IEA-R1 stored spent fuel and fuel elements from the core reactor. To record the available information and examination results it was elaborated a document in the format of a catalogue containing the proposed inspection program for the IEA-R1 stored spent fuel, the description of the visual inspection and sipping tests systems, a compilation of information and images result from the tests performed for all stored standard spent fuel element and, in annexes, copies of the reference documents. That document constitutes an important step of the effective implementation of the referred IEA-R1 spent fuel inspection program and can be used to address regulatory and operational needs for the demonstration, for example, of safe storage throughout the pool storage period. (author)

  4. The Liquisolid Technique: Based Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Izhar Ahmed Syed

    2012-04-01

    Full Text Available The “Liquisolid” technique is a novel and capable addition towards such an aims for solubility enhancement and dissolution improvement, thereby it increases the bioavailability. It contains liquid medications in powdered form. This technique is an efficient method for formulating water insoluble and water soluble drugs. This technique is based upon the admixture of drug loaded solutions with appropriate carrier and coating materials. The use of non-volatile solvent causes improved wettability and ensures molecular dispersion of drug in the formulation and leads to enhance solubility. By using hydrophobic carriers (non-volatile solvents one can modify release (sustained release of drugs by this technique. Liquisolid system is characterized by flow behavior, wettability, powder bed hydrophilicity, saturation solubility, drug content, differential scanning calorimetry, Fourier transform infra red spectroscopy, powder X-ray diffraction, scanning electron microscopy, in-vitro release and in-vivo evaluation. By using this technique, solubility and dissolution rate can be improved, sustained drug delivery systems be developed for the water soluble drugs.

  5. Interactive early warning technique based on SVDD

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    After reviewing current researches on early warning,it is found that"bad" data of some systems is not easy to obtain,which makes methods proposed by these researches unsuitable for monitored systems.An interactive early warning technique based on SVDD(support vector data description)is proposed to adopt"good" data as samples to overcome the difficulty in obtaining the"bad"data.The process consists of two parts:(1)A hypersphere is fitted on"good"data using SVDD.If the data object are outside the hypersphere,it would be taken as"suspicious";(2)A group of experts would decide whether the suspicious data is"bad"or"good",early warning messages would be issued according to the decisions.And the detailed process of implementation is proposed.At last,an experiment based on data of a macroeconomic system is conducted to verify the proposed technique.

  6. NFC based Inspection and Qualification Management (NIQM) System Preventing Counterfeit and Fraudulent Item

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Choong Koo; Kim, Young Joo [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2013-10-15

    Design, manufacturing, fabrication, transportation and installation of the devices and equipment for nuclear power plants shall be conducted under the thorough quality assurance program for the nuclear safety. However, from late in the 1980s, NRC began to issue a number of communications alerting licenses to issues involving counterfeit and fraudulent items. A number of incidents identified by the NRC in the 1980s and 1990s catalyzed the US nuclear industry to adopt standard precautions to guard against counterfeit items. The purpose of this paper is to develop the NFC (Near Field Communication) based Inspection and Qualification Management(NIQM) system preventing counterfeit and fraudulent items. NFC is one of the latest wireless communication technologies. As a short-range wireless connectivity technology, NFC offers safe-yet simple and intuitive-communication between electronic devices. As described above, NFC technology can be applied to the inspection and qualification management system very effectively to prevent counterfeit and fraudulent items. In addition, NIQM system can use existing data and information through the interface with legacy system.

  7. NFC based Inspection and Qualification Management (NIQM) System Preventing Counterfeit and Fraudulent Item

    International Nuclear Information System (INIS)

    Design, manufacturing, fabrication, transportation and installation of the devices and equipment for nuclear power plants shall be conducted under the thorough quality assurance program for the nuclear safety. However, from late in the 1980s, NRC began to issue a number of communications alerting licenses to issues involving counterfeit and fraudulent items. A number of incidents identified by the NRC in the 1980s and 1990s catalyzed the US nuclear industry to adopt standard precautions to guard against counterfeit items. The purpose of this paper is to develop the NFC (Near Field Communication) based Inspection and Qualification Management(NIQM) system preventing counterfeit and fraudulent items. NFC is one of the latest wireless communication technologies. As a short-range wireless connectivity technology, NFC offers safe-yet simple and intuitive-communication between electronic devices. As described above, NFC technology can be applied to the inspection and qualification management system very effectively to prevent counterfeit and fraudulent items. In addition, NIQM system can use existing data and information through the interface with legacy system

  8. Laser Remote Sensing: Velocimetry Based Techniques

    Science.gov (United States)

    Molebny, Vasyl; Steinvall, Ove

    Laser-based velocity measurement is an area of the field of remote sensing where the coherent properties of laser radiation are the most exposed. Much of the published literature deals with the theory and techniques of remote sensing. We restrict our discussion to current trends in this area, gathered from recent conferences and professional journals. Remote wind sensing and vibrometry are promising in their new scientific, industrial, military, and biomedical applications, including improving flight safety, precise weapon correction, non-contact mine detection, optimization of wind farm operation, object identification based on its vibration signature, fluid flow studies, and vibrometry-associated diagnosis.

  9. Graph based techniques for tag cloud generation

    DEFF Research Database (Denmark)

    Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

    2013-01-01

    Tag cloud is one of the navigation aids for exploring documents. Tag cloud also link documents through the user defined terms. We explore various graph based techniques to improve the tag cloud generation. Moreover, we introduce relevance measures based on underlying data such as ratings...... or citation counts for improved measurement of relevance of tag clouds. We show, that on the given data sets, our approach outperforms the state of the art baseline methods with respect to such relevance by 41 % on Movielens dataset and by 11 % on Bibsonomy data set....

  10. Application of the perspective-based reading technique in the nuclear I and C context. CORSICA work report 2011

    Energy Technology Data Exchange (ETDEWEB)

    Lahtinen, J.

    2012-07-01

    Inspections and reviews are one of the most effective ways of detecting errors in software development. The methods are also cost-effective because defects can be spotted early in the development, and thus the cost of repairing the defects is lower. Reading techniques are the procedures that are used in the inspection or review of a software artefact. The most common procedures are simple ad-hoc reading and a checklist- based reading technique. However, more advanced and detailed procedures have been created for various purposes. This report reviews the state-of-the-art software reading techniques used in inspections and reviews, and briefly reviews some of the empirical research in this context. The majority of the empirical research results indicate that, for example, perspective-based reading is more cost-effective and can detect more defects than more basic reading techniques. This report also describes how perspective-based reading can be applied to the inspection of nuclear-domain requirement specifications. For this purpose, seven perspective-based reading scenarios have been created. (orig.)

  11. Inspection and Repair Techniques and Strategies for Alloy 600 PWSCC in Reactor Vessel Head CRD Nozzles and Welds

    International Nuclear Information System (INIS)

    As a result of the Alloy 600 PWSCC CRD nozzle leaks discovered in the fall of 2000 and spring of 2001 in several US plants, the NRC has recommended a more pro-active effort by U.S. utilities to inspect similarly susceptible nozzles in all US plants. The primary safety concern is circumferential cracks that can permit the nozzle to separate from the head at high velocity and produce a large-break leak in the reactor vessel. A secondary concern is head leakage from any through-wall cracks in the nozzle or J-groove weld area. Although the fundamental weld and seal design are similar for all US PWR plants, the various surrounding geometry and repair probability considerations require multiple inspection and repair alternatives. Geometry issues include the head insulation design that influences the ability to perform visual examinations from above the head, and the presence or absence of thermal sleeves and funnels governing the type of NDE probes than can be used. Repair probability considerations primarily include the likelihood for repair of a small or large number of nozzles and the length of time the repair must last before a head replacement. This paper discusses the various inspection and repair alternatives offered by one service vendor and discusses a decision process for planning the inspection and repair effort. (authors)

  12. Language Based Techniques for Systems Biology

    DEFF Research Database (Denmark)

    Pilegaard, Henrik

    calculi have similarly been used for the study of bio-chemical reactive systems. In this dissertation it is argued that techniques rooted in the theory and practice of programming languages, language based techniques if you will, constitute a strong basis for the investigation of models of biological......Process calculus is the common denominator for a class of compact, idealised, domain-specific formalisms normally associated with the study of reactive concurrent systems within Computer Science. With the rise of the interactioncentred science of Systems Biology a number of bio-inspired process...... systems as formalised in a process calculus. In particular it is argued that Static Program Analysis provides a useful approach to the study of qualitative properties of such models. In support of this claim a number of static program analyses are developed for Regev’s BioAmbients – a bio-inspired variant...

  13. 3D VISION-BASED DIETARY INSPECTION FOR THE CENTRAL KITCHEN AUTOMATION

    OpenAIRE

    Yue-Min Jiang; Ho-Hsin Lee; Cheng-Chang Lien; Chun-Feng Tai; PiChun Chu; Ting-Wei Yang

    2014-01-01

    This paper proposes an intelligent and automatic dietary inspection system which can be applied to the dietary inspection for the application of central kitchen automation. The diet specifically designed for the patients are required with providing personalized diet such as low sodium intake or some necessary food. Hence, the proposed system can benefit the inspection process that is often performed manually. In the proposed system, firstly, the meal box can be detected and loc...

  14. Path Planning Based on Dimension Reduction and Region Clipping for Aircraft Fuel Tank Inspection Robot

    Directory of Open Access Journals (Sweden)

    Qingji Gao

    2014-06-01

    Full Text Available A continuum robot for inspecting aircraft fuel tank is designed to improve the performance of manual maintenance. Path planning for this kind of robot is challenging due to their complex kinematics models. In an environment without obstacles, a strategy of path planning is proposed in this paper. Dimension reduction method is presented and an imaginary straight line between the starting point and the target is made up as a reference line to simplify the problem. A novel search method based on region clipping deduced from continuity analysis of position function is proposed to decrease computing time complexity. Minimum distance summation (MDS is calculated to decide the optimal path relatively. Simulation results and analysis demonstrate excellent performance of region clipping search method and feasibility of path planning.

  15. Wavelet based edge detection algorithm for web surface inspection of coated board web

    Science.gov (United States)

    Barjaktarovic, M.; Petricevic, S.

    2010-07-01

    This paper presents significant improvement of the already installed vision system. System was designed for real time coated board inspection. The improvement is achieved with development of a new algorithm for edge detection. The algorithm is based on the redundant (undecimated) wavelet transform. Compared to the existing algorithm better delineation of edges is achieved. This yields to better defect detection probability and more accurate geometrical classification, which will provide additional reduction of waste. Also, algorithm will provide detailed classification and more reliably tracking of defects. This improvement requires minimal changes in processing hardware, only a replacement of the graphic card would be needed, adding only negligibly to the system cost. Other changes are accomplished entirely in the image processing software.

  16. Wavelet based edge detection algorithm for web surface inspection of coated board web

    International Nuclear Information System (INIS)

    This paper presents significant improvement of the already installed vision system. System was designed for real time coated board inspection. The improvement is achieved with development of a new algorithm for edge detection. The algorithm is based on the redundant (undecimated) wavelet transform. Compared to the existing algorithm better delineation of edges is achieved. This yields to better defect detection probability and more accurate geometrical classification, which will provide additional reduction of waste. Also, algorithm will provide detailed classification and more reliably tracking of defects. This improvement requires minimal changes in processing hardware, only a replacement of the graphic card would be needed, adding only negligibly to the system cost. Other changes are accomplished entirely in the image processing software.

  17. NRU light water reflector inspections

    International Nuclear Information System (INIS)

    In 2009 May, the National Research Universal (NRU) calandria leaked. In the next year the calandria was inspected with six new techniques, repaired, and the repair inspected with four additional new techniques. The calandria is surrounded by a light water reflector vessel. Concerns that the same corrosion mechanism may have damaged the reflector vessel led to plans to inspect the full circumference of the reflector wall for corrosion damage, through a 64 mm diameter port, from 10 m away, while inspecting from the corroded surface. The ultrasonic technique is intended to produce a very fine inspection grid, through the corroded surface, using a very small probe body over the approximately 5 m2 to be inspected. The calandria vessel inspections were successfully performed, in a short time period, under difficult conditions. This paper will discuss Operating Experience (OPEX) from the 2009/2010 calandria wall inspections and industry dialogue that were applied to the Reflector Wall Inspection (RWI) project. Interaction with the CANDU Inspection Qualification Bureau (CIQB) on procedures, training plans, and mock-up training, led to improvements in how these activities were performed for the RWI project. Experience with shift turnover meetings led to improvements in how the inspection team captures lessons learned, trends issues, and eliminates reoccurring design and procedure problems. Experience with collected and analyzed data, inspection shift logs, and video captured from inspections and repairs, were used to improve inspection performance. Finally, OPEX from radiation/activation and the calibration process reduced dose through tool design and procedure changes. (author)

  18. Hand-eye-vision based control for an inspection robot’s autonomous line grasping

    Institute of Scientific and Technical Information of China (English)

    王伟; 吴功平; 白玉成; 肖华; 杨智勇; 严宇; 何缘; 徐显金; 苏帆

    2014-01-01

    In order to ensure that the off-line arm of a two-arm-wheel combined inspection robot can reliably grasp the line in case of autonomous obstacle crossing, a control method is proposed for line grasping based on hand-eye visual servo. On the basis of the transmission line’s geometrical characteristics and the camera’s imaging principle, a line recognition and extraction method based on structure constraint is designed. The line’s intercept and inclination are defined in an imaging space to represent the robot’s change of pose and a law governing the pose decoupling servo control is developed. Under the integrated consideration of the influence of light intensity and background change, noise (from the camera itself and electromagnetic field) as well as the robot’s kinetic inertia on the robot’s imaging quality in the course of motion and the grasping control precision, a servo controller for grasping the line of the robot’s off-line arm is designed with the method of fuzzy control. An experiment is conducted on a 1:1 simulation line using an inspection robot and the robot is put into on-line operation on a real overhead transmission line, where the robot can grasp the line within 18 s in the case of autonomous obstacle-crossing. The robot’s autonomous line-grasping function is realized without manual intervention and the robot can grasp the line in a precise, reliable and efficient manner, thus the need of actual operation can be satisfied.

  19. Biometric Iris Recognition Based on Hybrid Technique

    Directory of Open Access Journals (Sweden)

    Khattab M. Ali Alheeti

    2011-12-01

    Full Text Available Iris Recognition is one of the important biometric recognition systems that identify people based on theireyes and iris. In this paper the iris recognition algorithm is implemented via histogram equalization andwavelet techniques. In this paper the iris recognition approach is implemented via many steps, these stepsare concentrated on image capturing, enhancement and identification. Different types of edge detectionmechanisms; Canny scheme, Prewitt scheme, Roberts scheme and Sobel scheme are used to detect irisboundaries in the eyes digital image. The implemented system gives adequate results via different types ofiris images.

  20. Inservice inspection of primary circuit components of VVER 440-Type nuclear power plants

    International Nuclear Information System (INIS)

    The Technical Research Centre of Finland (VTT) has since 1979 performed the inservice inspections of the primary circuits, steam generators and other ASME XI safety class 1 components of the Loviisa reactors (VVER440). A presentation of the performance of the inservice inspections is given in this paper. The main volumetric examination method used in the inservice inspection is the ultrasonic examination. The primary piping of Loviisa reactors is made of austenitic steel and the conventional ultrasonic technique cannot be applied due to the strong attenuation of ultrasonic waves. The special technique developed for the ultrasonic inspection of the welds in the primary piping as well as for the welds of main gate valves will be presented. As these inspections especially in older reactors have to be carried out in a radioactive environment, mechanized inspection equipment has been constructed to perform the work. An inspection manipulator is also used to inspect the base metal of the primary circuit in areas where mixing up of hot and cool water can cause thermal shocks and consequently lead to cracking. Because the ultrasonic inspection of main gate valves is strongly restricted by the valve geometry and material properties, an acoustic emission technique has been developed to improve the reliability of the inservice inspections. For steam generator tubing the eddy current inspection technique has been applied. Due to the different design of steam generators in VVER440 reactors, the performance of the inspection differs from the practice normally applied in U-tube steam generators. For the inspection of studs in primary circuit components both ultrasonic and eddy current techniques have been developed. A mechanized inspection equipment has been constructed to perform both ultrasonic and eddy current inspections simultaneously for large studs. For smaller studs and for threads in stud holes e.g. in steam generators mechanized eddy current inspection technique has

  1. Artificial Intelligence based technique for BTS placement

    International Nuclear Information System (INIS)

    The increase of the base transceiver station (BTS) in most urban areas can be traced to the drive by network providers to meet demand for coverage and capacity. In traditional network planning, the final decision of BTS placement is taken by a team of radio planners, this decision is not fool proof against regulatory requirements. In this paper, an intelligent based algorithm for optimal BTS site placement has been proposed. The proposed technique takes into consideration neighbour and regulation considerations objectively while determining cell site. The application will lead to a quantitatively unbiased evaluated decision making process in BTS placement. An experimental data of a 2km by 3km territory was simulated for testing the new algorithm, results obtained show a 100% performance of the neighbour constrained algorithm in BTS placement optimization. Results on the application of GA with neighbourhood constraint indicate that the choices of location can be unbiased and optimization of facility placement for network design can be carried out

  2. A vision-based self-calibration method for robotic visual inspection systems.

    Science.gov (United States)

    Yin, Shibin; Ren, Yongjie; Zhu, Jigui; Yang, Shourui; Ye, Shenghua

    2013-01-01

    A vision-based robot self-calibration method is proposed in this paper to evaluate the kinematic parameter errors of a robot using a visual sensor mounted on its end-effector. This approach could be performed in the industrial field without external, expensive apparatus or an elaborate setup. A robot Tool Center Point (TCP) is defined in the structural model of a line-structured laser sensor, and aligned to a reference point fixed in the robot workspace. A mathematical model is established to formulate the misalignment errors with kinematic parameter errors and TCP position errors. Based on the fixed point constraints, the kinematic parameter errors and TCP position errors are identified with an iterative algorithm. Compared to the conventional methods, this proposed method eliminates the need for a robot-based-frame and hand-to-eye calibrations, shortens the error propagation chain, and makes the calibration process more accurate and convenient. A validation experiment is performed on an ABB IRB2400 robot. An optimal configuration on the number and distribution of fixed points in the robot workspace is obtained based on the experimental results. Comparative experiments reveal that there is a significant improvement of the measuring accuracy of the robotic visual inspection system. PMID:24300597

  3. A PCA and ELM Based Adaptive Method for Channel Equalization in MFL Inspection

    Directory of Open Access Journals (Sweden)

    Zhenning Wu

    2014-01-01

    Full Text Available Magnetic flux leakage (MFL as an efficient method for pipeline flaw detection plays important role in pipeline safety. This nondestructive test technique assesses the health of the buried pipeline. The signal is gathered by an array of hall-effect sensors disposed at the magnetic neutral plane of a pair of permanent magnet in the pipeline inspection gauge (PIG clinging to the inner surface of the pipe wall. The magnetic flux measured by the sensors reflects the health condition of the pipe. The signal is influenced by not only the condition of the pipe, but also by the lift-off value of the sensors and various properties of electronic component. The consistency of the position of the sensors is almost never satisfied and each sensor measures differently. In this paper, a new scheme of channel equalization is proposed for MFL signal in order to correct sensor misalignments, which eventually improves accuracy of defect characterization. The algorithm proposed in this paper is adaptive to the effects of error on the disposition of the sensor due to manufacturing imperfections and movements of the sensors. The algorithm is tested by data acquired from an experimental pipeline. The results show the effectiveness of the proposed algorithm.

  4. Reliable evaluation of acceptability of weld for final disposal based on the canister copper weld inspection using different NDT methods

    International Nuclear Information System (INIS)

    The inspection of the sealing weld is an important phase for the evaluation of the acceptability of final disposal canister, but the weld is only a part of the 3D shielding of copper shell. The main tasks for reliable NDT evaluation requires an extensive evaluation of the parameters - which contains typical inspection related items like repeatability, S/N ratio, POD, setting up the equipment for inspection, and all practices for inspections. The other parameters are material parameters, their variation must be taken into account in the evaluation of NDT reliability. Further parameters include human factors, i. e. human inspectors and their interaction with technical systems; their effects were studied on an example of the evaluation of eddy current data. Final parameters are related to evaluation of detected defects, which means sizing and base for acceptance and this can be done in different ways. Some examples are given and results are compared with different methods for instance between radiographic testing and ultrasonic testing by raw data analysis and PA-SAFT results. Also, preliminary curves for the evaluation of metallographic results of 55 defects will be shown by EB weld measurements. Some practical items concerning copper inspections will be also discussed related to acceptability.

  5. Inspection and repair techniques in the reactor vessel of the experimental fast reactor Joyo. Development of repair techniques for UCS replacement of Joyo

    International Nuclear Information System (INIS)

    Development of repair techniques in the reactor vessel of sodium cooled fast reactors is important to secure its safety and integrity. With the incident as an opportunity, repair techniques for Upper Core Structure (UCS) replacement was developed in Joyo. Since the UCS of Joyo was designed as an eternal structure and it has high dose rate due to the irradiation for over 30 years, the following subjects were mainly discussed in this study as critical tasks. (1) Prevention of deformation during jack-up and retrieval of the UCS, (2) Reducing UCS cask weight In order to resolve above (1), the allowable load to prevent the deformation of the UCS and guide sleeve were evaluated using finite element method analysis code with 3-D model. Furthermore, the general design of the equipment were established based on the requirement of monitoring and control of the factors (load, flatness, inclination and pull-up speed etc.) and gap observation to achieve UCS jack-up and retrieval. Concerning with above (2), multistage cask without crane and door valve was suggested in this study. As a result of this study, total weight of cask (including UCS) was reduced to be less than 100ton, which is the maximum load of the crane in the reactor containment vessel of Joyo. The UCS replacement is scheduled in 2014. Achievement of the UCS replacement and accumulated experience will be able to provide valuable insights for further improving and verifying repair techniques in sodium cooled fast reactors. (author)

  6. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper an optimal inspection strategy for concrete bridges based on periodic routine and detailed inspections is presented. The failure mode considered is corrosion of the reinforcement due to chlorides. A simple modelling of the corrosion and of the inspection strategy is presented. The...... optimal inspection strategy is determined from an optimization problem, where the design variables are time intervals between detailed inspections and the concrete cover. The strategy is illustrated on a simple structure, namely a reinforced concrete beam....

  7. Estimation of Characteristics of a Software Team for Implementing Effective Inspection Process through Inspection Performance Metric

    CERN Document Server

    Nair, T R Gopalakrishnan

    2011-01-01

    The continued existence of any software industry depends on its capability to develop nearly zero-defect product, which is achievable through effective defect management. Inspection has proven to be one of the promising techniques of defect management. Introductions of metrics like, Depth of Inspection (DI, a process metric) and Inspection Performance Metric (IPM, a people metric) enable one to have an appropriate measurement of inspection technique. This article elucidates a mathematical approach to estimate the IPM value without depending on shop floor defect count at every time. By applying multiple linear regression models, a set of characteristic coefficients of the team is evaluated. These coefficients are calculated from the empirical projects that are sampled from the teams of product-based and service-based IT industries. A sample of three verification projects indicates a close match between the IPM values obtained from the defect count (IPMdc) and IPM values obtained using the team coefficients usi...

  8. Modeling and optimizing periodically inspected software rejuvenation policy based on geometric sequences

    International Nuclear Information System (INIS)

    Software aging is characterized by an increasing failure rate, progressive performance degradation and even a sudden crash in a long-running software system. Software rejuvenation is an effective method to counteract software aging. A periodically inspected rejuvenation policy for software systems is studied. The consecutive inspection intervals are assumed to be a decreasing geometric sequence, and upon the inspection times of software system and its failure features, software rejuvenation or system recovery is performed. The system availability function and cost rate function are obtained, and the optimal inspection time and rejuvenation interval are both derived to maximize system availability and minimize cost rate. Then, boundary conditions of the optimal rejuvenation policy are deduced. Finally, the numeric experiment result shows the effectiveness of the proposed policy. Further compared with the existing software rejuvenation policy, the new policy has higher system availability. - Highlights: • A periodically inspected rejuvenation policy for software systems is studied. • A decreasing geometric sequence is used to denote the consecutive inspection intervals. • The optimal inspection times and rejuvenation interval are found. • The new policy is capable of reducing average cost and improving system availability

  9. On automatic visual inspection of reflective surfaces

    DEFF Research Database (Denmark)

    Kulmann, Lionel

    1995-01-01

    surveyed visual inspection system design methods and presented available image processing hardware to perform high resolution image capture. We present general usable practical visual inspection system solutions, when performing high resolution visual inspection of surfaces. We have presented known and new...... surfaces, providing new and exciting applications subject to automated visual inspection. Several contextual features have been surveyed along with introduction of novel methods to perform data-dependent enhancement of local surface appearance . Morphological methods have been described and utilized in...... algorithms for detecting 3-dimensional surface damages based on images from a novel structured lighting setup enhancing the appearance of these defects in specular surfaces. A hardware implementable polynomial classifier structure has been described and compared to better known techniques based on...

  10. Comparison of a magnetostrictive and an EMAT guided wave technique for the long-range pipe inspection

    International Nuclear Information System (INIS)

    An EMAT sensor and a magnetostrictive sensor were developed for the long-range guided wave inspection of pipe. An array of EMAT were designed and fabricated for the generation and reception of torsional guided waves. Also a magnetostrictive sensor with a circumferentially magnetized Ni strip and coil for alternating magnetization were fabricated for torsional guided waves, T(0,1) mode. These two approaches were applied to the feeder pipe with various artificial notches. The advantages and limitations of the EMAT method and magnetostrictive method compared in the viewpoint of field application.

  11. To develop a flying fish egg inspection system by a digital imaging base system

    Science.gov (United States)

    Chen, Chun-Jen; Jywe, Wenyuh; Hsieh, Tung-Hsien; Chen, Chien Hung

    2015-07-01

    This paper develops an automatic optical inspection system for flying fish egg quality inspection. The automatic optical inspection system consists of a 2-axes stage, a digital camera, a lens, a LED light source, a vacuum generator, a tube and a tray. This system can automatically find the particle on the flying egg tray and used stage to driver the tube onto the particle. Then use straw and vacuum generator to pick up the particle. The system pick rate is about 30 particles per minute.

  12. Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

    Science.gov (United States)

    Prayogo, Galang Sandy; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

    2016-04-01

    Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

  13. Process flow measurement based on tracer techniques

    International Nuclear Information System (INIS)

    Flow measurement methods based on the tracer techniques are the transit time method as well as methods based on tracer dilution. These methods can be applied to the on-site calibration of flowmeters and to measuring the flowrate where no flowmeter is installed. The accuracy of the tracer methods depends on the prevailing measuring conditions. In this report the accuracy of the transit time method under field conditions is estimated to be 1-2% on the 99,7% confidence level. The accuracy of the isotope dilution method is estimated as slightly better, namely about 0.5% at its best. An even better accuracy, about 0.2%, could be achieved by developing the method and the measuring equipment. Tests were carried out with the transit time method for water and steam flow. While measuring water flow the effect of different measuring parameters upon the repeatability of the method were looked into. Such were the number of the detectors and the distance between the measuring points. Different means of tracer injection were tested, as well. These had less effect than expected. The accuracies achieved in steam flow measurements were of the same order of magnitude as in water flow measurements. The tracers used were 137mBa for water flow and 41Ar for steam flow measurements

  14. Inspection Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — FDA is disclosing the final inspection classification for inspections related to currently marketed FDA-regulated products. The disclosure of this information is...

  15. 40-Gbps optical backbone network deep packet inspection based on FPGA

    Science.gov (United States)

    Zuo, Yuan; Huang, Zhiping; Su, Shaojing

    2014-11-01

    In the era of information, the big data, which contains huge information, brings about some problems, such as high speed transmission, storage and real-time analysis and process. As the important media for data transmission, the Internet is the significant part for big data processing research. With the large-scale usage of the Internet, the data streaming of network is increasing rapidly. The speed level in the main fiber optic communication of the present has reached 40Gbps, even 100Gbps, therefore data on the optical backbone network shows some features of massive data. Generally, data services are provided via IP packets on the optical backbone network, which is constituted with SDH (Synchronous Digital Hierarchy). Hence this method that IP packets are directly mapped into SDH payload is named POS (Packet over SDH) technology. Aiming at the problems of real time process of high speed massive data, this paper designs a process system platform based on ATCA for 40Gbps POS signal data stream recognition and packet content capture, which employs the FPGA as the CPU. This platform offers pre-processing of clustering algorithms, service traffic identification and data mining for the following big data storage and analysis with high efficiency. Also, the operational procedure is proposed in this paper. Four channels of 10Gbps POS signal decomposed by the analysis module, which chooses FPGA as the kernel, are inputted to the flow classification module and the pattern matching component based on TCAM. Based on the properties of the length of payload and net flows, buffer management is added to the platform to keep the key flow information. According to data stream analysis, DPI (deep packet inspection) and flow balance distribute, the signal is transmitted to the backend machine through the giga Ethernet ports on back board. Practice shows that the proposed platform is superior to the traditional applications based on ASIC and NP.

  16. Flying Robot Based Viewpoint Selection for the Electricity Transmission Equipment Inspection

    OpenAIRE

    Chang-an Liu; Rui-fang Dong; Hua Wu

    2014-01-01

    In the process of inspection for the electricity transmission equipment using flying robots, an automatic way to find the best viewpoint to get the high quality of image would be beneficial to observe the state of the electricity transmission equipment. Finding the best viewpoint belongs to the viewpoint selection problem. A strategy is proposed in this paper to find the best viewpoint for the electricity transmission equipment inspection, according to which the candidate viewpoints can be ge...

  17. Risk-Informed Decisions Optimization in Inspection and Maintenance

    International Nuclear Information System (INIS)

    The Risk-Informed Approach (RIA) used to support decisions related to inspection and maintenance program is considered. The use of risk-informed methods can help focus the adequate in-service inspections and control on the more important locations of complex dynamic systems. The focus is set on the highest risk measured as conditional core damage frequency, which is produced by the frequencies of degradation and final failure at different locations combined with the conditional failure consequence probability. The probabilities of different degradation states per year and consequences are estimated quantitatively. The investigation of inspection and maintenance process is presented as the combination of deterministic and probabilistic analysis based on general risk-informed model, which includes the inspection and maintenance program features. Such RIA allows an optimization of inspection program while maintaining probabilistic and fundamental deterministic safety requirements. The failure statistics analysis is used as well as the evaluation of reliability of inspections. The assumptions regarding the effectiveness of the inspection methods are based on a classification of the accessibility of the welds during the inspection and on the different techniques used for inspection. The probability of defect detection is assumed to depend on the parameters either through logarithmic or logit transformation. As example the modeling of the pipe systems inspection process is analyzed. The means to reduce a number of inspection sites and the cumulative radiation exposure to the NPP inspection personnel with a reduction of overall risk is presented together with used and developed software. The developed software can perform and administrate all the risk evaluations and ensure the possibilities to compare different options and perform sensitivity analysis. The approaches to define an acceptable level of risk are discussed. These approaches with appropriate software in

  18. Non-Destructive Techniques Based on Eddy Current Testing

    Directory of Open Access Journals (Sweden)

    Ernesto Vázquez-Sánchez

    2011-02-01

    Full Text Available Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future.

  19. A portable nondestructive real-time detection system for inspection of pork quality attributes using Vis/NIR spectral technique

    Science.gov (United States)

    Sun, Hongwei; Peng, Yankun

    2016-05-01

    There are many preferences expressing the quality of pork: color, pH, especially TVB-N content. Different quality pork has different spectral feature (in range of 400 to 1000nm). To detect quality attributes of pork easily, real-time, nondestructively, a portable device based on Vis/NIR spectral technique was developed. The device is mainly made up of four units: light source, spectrometer, controller and display screen. After hardware platform established, reflectance spectra of 44 samples were collected from this system. And their physicochemical characteristics such as color parameters, pH value and the content of total volatile basic-nitrogen (TVB-N) were measured in standard methods. Spectrum data acquired were processed by Savitzky-Golay filter(S-G) for noise removal, and then operated by standard normal variable transformation (SNV) for baseline drifts relieving. The partial least squares regression (PLSR) was used to build prediction models for L*, a*, b* pH* and TVB-N content, which could gain good prediction results with Rp of 0.92, 0.91, 0.92, 0.95 and 0.96 respectively. The results demonstrated that this device could be a promising tool applied to detecting pork quality attributes portably, real-time and nondestructively.

  20. Decision making for stable inspection planning of deteriorating structures based on constraint reliability and uncertainties

    Directory of Open Access Journals (Sweden)

    Jalal alsarraf

    2014-06-01

    Full Text Available Life-time cost minimization is considered as the optimal criterion for planning of inspection, repair and maintenance of structures. However, most of the probabilities and the cost items related to the cost analysis generally contain inevitable uncertainties in actual cases. The appropriateness of inspection planning may be lost by several errors induced by such uncertainties. In this study, a cost minimization method with the constraint of reliability is developed in order to obtain stable inspection planning against the estimation errors of the parameters. In the analysis, the life-time cost optimization is carried out under the constraint that the failure probabilities of the members are controlled below the respective target values allowed for the members. First, initial target failure probabilities are assumed for each member. Then, the robustness of the inspection planning is investigated by adjusting the parameters within the range of uncertainties. The initial values of the target failure probabilities are altered until an acceptable result is obtained. The applicability of the proposed method is examined for a structure with several uncertain parameters. A sequential cost minimization method is employed to optimize the life-time cost. It is made clear that by using this approach, the stability of the life-time cost is maintained without losing the benefit of the cost minimization method. Keywords: Crack, Fatigue, Inspection, Numerical Model, Reliability, Structure.

  1. FLOWCER - a flowmeter based on radiotracer techniques

    International Nuclear Information System (INIS)

    One of the most difficult problems in the field of flow measurement is the lack of a portable, clamp-on type of flowmeter of good accuracy. This is a serious restriction in non-continuous flow measurements and on-site calibrations of flow meters. One possibility of constructing a meter capable for these measurements is to use tracer techniques, particularly radioisotope tracers. A flow measurement instrument, FLOWCER, has been developed in the Reactor Laboratory of the Technical Research Centre of Finland (VTT). The instrument is based on the radioisotope transit time method. The device can be used for the accurate instantaneous measurement of volume flow rate in ducts. The tracer used is 137mBa produced in a portable isotope generator. Because of the short half-life (2.6 min) of 137mBa the measurement is radiologically very safe. The device consists of the isotope generator, an injection device for the tracer, radiation detectors, a data logger unit and a micro-computer. Also a transducer for various other quantities than flow may be connected to the analog input channels of the FLOWCER. The measurement program can be modified for measurements of different types. The FLOWCER has been used for the measurememts of energy and material balances, for the on-site calibrations of flow meters and for pump efficiency analysis. The application most frequently used has been the on-site calibration of flow meters. According to the present experience (over 100 calibrated flow meters) the accuracy level of flow measurements can be increased by a factor of ten or more by using the transit time method for on-site calibration

  2. Modeling of a remote inspection system for NSSS components

    International Nuclear Information System (INIS)

    Safety inspection for safety-critical unit of nuclear power plant has been processed using off-line technology. Thus we can not access safety inspection system and inspection data via network such as internet. We are making an on-line control and data access system based on WWW and JAVA technologies which can be used during plant operation to overcome these problems. Users can access inspection systems and inspection data only using web-browser. This report discusses about analysis of the existing remote system and essential techniques such as Web, JAVA, client/server model, and multi-tier model. This report also discusses about a system modeling that we have been developed using these techniques and provides solutions for developing an on-line control and data access system

  3. Modeling of a remote inspection system for NSSS components

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yoo Rark; Kim, Jae Hee; Lee, Jae Cheol

    2003-03-01

    Safety inspection for safety-critical unit of nuclear power plant has been processed using off-line technology. Thus we can not access safety inspection system and inspection data via network such as internet. We are making an on-line control and data access system based on WWW and JAVA technologies which can be used during plant operation to overcome these problems. Users can access inspection systems and inspection data only using web-browser. This report discusses about analysis of the existing remote system and essential techniques such as Web, JAVA, client/server model, and multi-tier model. This report also discusses about a system modeling that we have been developed using these techniques and provides solutions for developing an on-line control and data access system.

  4. Inspection Robot Based Mobile Sensing and Power Line Tracking for Smart Grid.

    Science.gov (United States)

    Byambasuren, Bat-Erdene; Kim, Donghan; Oyun-Erdene, Mandakh; Bold, Chinguun; Yura, Jargalbaatar

    2016-01-01

    Smart sensing and power line tracking is very important in a smart grid system. Illegal electricity usage can be detected by remote current measurement on overhead power lines using an inspection robot. There is a need for accurate detection methods of illegal electricity usage. Stable and correct power line tracking is a very prominent issue. In order to correctly track and make accurate measurements, the swing path of a power line should be previously fitted and predicted by a mathematical function using an inspection robot. After this, the remote inspection robot can follow the power line and measure the current. This paper presents a new power line tracking method using parabolic and circle fitting algorithms for illegal electricity detection. We demonstrate the effectiveness of the proposed tracking method by simulation and experimental results. PMID:26907274

  5. Inspection Robot Based Mobile Sensing and Power Line Tracking for Smart Grid

    Directory of Open Access Journals (Sweden)

    Bat-erdene Byambasuren

    2016-02-01

    Full Text Available Smart sensing and power line tracking is very important in a smart grid system. Illegal electricity usage can be detected by remote current measurement on overhead power lines using an inspection robot. There is a need for accurate detection methods of illegal electricity usage. Stable and correct power line tracking is a very prominent issue. In order to correctly track and make accurate measurements, the swing path of a power line should be previously fitted and predicted by a mathematical function using an inspection robot. After this, the remote inspection robot can follow the power line and measure the current. This paper presents a new power line tracking method using parabolic and circle fitting algorithms for illegal electricity detection. We demonstrate the effectiveness of the proposed tracking method by simulation and experimental results.

  6. DCT-based cyber defense techniques

    Science.gov (United States)

    Amsalem, Yaron; Puzanov, Anton; Bedinerman, Anton; Kutcher, Maxim; Hadar, Ofer

    2015-09-01

    With the increasing popularity of video streaming services and multimedia sharing via social networks, there is a need to protect the multimedia from malicious use. An attacker may use steganography and watermarking techniques to embed malicious content, in order to attack the end user. Most of the attack algorithms are robust to basic image processing techniques such as filtering, compression, noise addition, etc. Hence, in this article two novel, real-time, defense techniques are proposed: Smart threshold and anomaly correction. Both techniques operate at the DCT domain, and are applicable for JPEG images and H.264 I-Frames. The defense performance was evaluated against a highly robust attack, and the perceptual quality degradation was measured by the well-known PSNR and SSIM quality assessment metrics. A set of defense techniques is suggested for improving the defense efficiency. For the most aggressive attack configuration, the combination of all the defense techniques results in 80% protection against cyber-attacks with PSNR of 25.74 db.

  7. Supplier and Producer Profit Sharing Models Based on Inspection Sampling Policy

    OpenAIRE

    Chiuh-Cheng Chyu; I-Ping Huang

    2010-01-01

    This research presents three profit sharing models of a key item in a two-echelon supply chain production. The first model maximizes the supplier’s profit while allowing the producer to take his own optimal inspection sampling policy. The second model is developed exclusively to the supplier’s advantage. The last model adopts a collaborative strategy that permits both parties to negotiate an inspection policy, and aims to maximize total profit. In this two-echelon supply chain, the supplier d...

  8. A fluorescent micro capsule manufacture of magnetic particle testing for advanced inspection technique of heat exchanger tube

    International Nuclear Information System (INIS)

    Fine magnetic particles having UV fluorescence are commonly used in magnetic crack detection technique. Stress corrosion cracking sometimes happens in nuclear power plants. To apply this technique to maintain the heat exchanger tubes, it is desired that these particles has performance to be collected with ease. To collect these fine magnetic particles from millimeter size crack depth, a chemosynthesis technique to produce the micro capsules successfully produced hundreds micron sized capsules containing the fine magnetic particles. The synthesized micro capsules indicated the collective sensitivity for lines of magnetic force. (author)

  9. Sensor-based monitoring and inspection of surface morphology in ultraprecision manufacturing processes

    Science.gov (United States)

    Rao, Prahalad Krishna

    This research proposes approaches for monitoring and inspection of surface morphology with respect to two ultraprecision/nanomanufacturing processes, namely, ultraprecision machining (UPM) and chemical mechanical planarization (CMP). The methods illustrated in this dissertation are motivated from the compelling need for in situ process monitoring in nanomanufacturing and invoke concepts from diverse scientific backgrounds, such as artificial neural networks, Bayesian learning, and algebraic graph theory. From an engineering perspective, this work has the following contributions: 1. A combined neural network and Bayesian learning approach for early detection of UPM process anomalies by integrating data from multiple heterogeneous in situ sensors (force, vibration, and acoustic emission) is developed. The approach captures process drifts in UPM of aluminum 6061 discs within 15 milliseconds of their inception and is therefore valuable for minimizing yield losses. 2. CMP process dynamics are mathematically represented using a deterministic multi-scale hierarchical nonlinear differential equation model. This process-machine inter-action (PMI) model is evocative of the various physio-mechanical aspects in CMP and closely emulates experimentally acquired vibration signal patterns, including complex nonlinear dynamics manifest in the process. By combining the PMI model predictions with features gathered from wirelessly acquired CMP vibration signal patterns, CMP process anomalies, such as pad wear, and drifts in polishing were identified in their nascent stage with high fidelity (R2 ~ 75%). 3. An algebraic graph theoretic approach for quantifying nano-surface morphology from optical micrograph images is developed. The approach enables a parsimonious representation of the topological relationships between heterogeneous nano-surface fea-tures, which are enshrined in graph theoretic entities, namely, the similarity, degree, and Laplacian matrices. Topological invariant

  10. Flood alert system based on bayesian techniques

    Science.gov (United States)

    Gulliver, Z.; Herrero, J.; Viesca, C.; Polo, M. J.

    2012-04-01

    The problem of floods in the Mediterranean regions is closely linked to the occurrence of torrential storms in dry regions, where even the water supply relies on adequate water management. Like other Mediterranean basins in Southern Spain, the Guadalhorce River Basin is a medium sized watershed (3856 km2) where recurrent yearly floods occur , mainly in autumn and spring periods, driven by cold front phenomena. The torrential character of the precipitation in such small basins, with a concentration time of less than 12 hours, produces flash flood events with catastrophic effects over the city of Malaga (600000 inhabitants). From this fact arises the need for specific alert tools which can forecast these kinds of phenomena. Bayesian networks (BN) have been emerging in the last decade as a very useful and reliable computational tool for water resources and for the decision making process. The joint use of Artificial Neural Networks (ANN) and BN have served us to recognize and simulate the two different types of hydrological behaviour in the basin: natural and regulated. This led to the establishment of causal relationships between precipitation, discharge from upstream reservoirs, and water levels at a gauging station. It was seen that a recurrent ANN model working at an hourly scale, considering daily precipitation and the two previous hourly values of reservoir discharge and water level, could provide R2 values of 0.86. BN's results slightly improve this fit, but contribute with uncertainty to the prediction. In our current work to Design a Weather Warning Service based on Bayesian techniques the first steps were carried out through an analysis of the correlations between the water level and rainfall at certain representative points in the basin, along with the upstream reservoir discharge. The lower correlation found between precipitation and water level emphasizes the highly regulated condition of the stream. The autocorrelations of the variables were also

  11. DEVELOPMENT OF INSPECTION SYSTEM FOR CORROSION CRACK IN R.C. FOR SECOND TUNNEL LINING BY USING KNOWLEDGE-BASED SYSTEM

    Directory of Open Access Journals (Sweden)

    Yousif Abdulwahid Mansoor

    2012-01-01

    Full Text Available During the last two or three decades, incidence of failure of reinforced concrete structures has been seen widely for many reasons, such as increasing service loads and/or durability problems and the economic losses due to such failures are costly. Nowadays, the size and the form of repair and rehabilitation market are too large since there has been an increased emphasis on repair and retrofitting of defected structures over demolition and new construction. For safety in concrete tunnel, periodic inspection has been conducted using many testing technologies and techniques. However, these technologies cannot replace visual inspection because of their slow and complicated procedures. For this reason, the Knowledge-Based Systems (KBS are used with lab tests results to diagnose R.C tunnel lining corrosion crack damage (DICRCTL. In this study, we attempt to propose an alternative to the human expert, to give technical decisions in diagnosing corrosion crack damages in second segment of R.C. tunnel lining. To overcome this requirement, an expert system is developed to achieve the research aim. This proposed system was constructed on a knowledge base that incorporates with the gathered information, tests in the form of rules which is suitable to implement in an expert system environment to diagnostic advisory nature. The proposed application results show an easy, fast and satisfactory answer to engineering needs.

  12. Steam Generator Inspection Planning Expert System

    International Nuclear Information System (INIS)

    Applying Artificial Intelligence technology to steam generator non-destructive examination (NDE) can help identify high risk locations in steam generators and can aid in preparing technical specification compliant eddy current test (ECT) programs. A steam Generator Inspection Planning Expert System has been developed which can assist NDE or utility personnel in planning ECT programs. This system represents and processes its information using an object oriented declarative knowledge base, heuristic rules, and symbolic information processing, three artificial intelligence based techniques incorporated in the design. The output of the system is an automated generation of ECT programs. Used in an outage inspection, this system significantly reduced planning time

  13. A risk-based approach to maintenance planning utilizing in-line inspection data

    Energy Technology Data Exchange (ETDEWEB)

    Fenyvesi, L.L. [TransCanada PipeLines Ltd., Calgary, AB (Canada); Colquhoun, I.; Kania, R.; Gu, B. [GE Power Systems (Canada)

    2004-07-01

    The pipeline industry routinely performs in-line inspections (ILI) to manage external corrosion in pipelines. ILIs are followed by repairs of defects that fail a deterministic criterion. Re-inspection is then performed after a prescribed time interval has elapsed. However, due to uncertainties associated with magnetic flux leakage (MFL) defect sizing and corrosion growth rates, a deterministic repair and re-inspection may result in nonessential maintenance expenditure. In addition, critical features may sometimes remain unidentified. This paper suggested that in order to evaluate the sensitivity of a defect's failure probability more effectively, a better approach would be to evaluate corrosion defects by viewing the process as an analysis of a set of stochastic variables rather than deterministic values. Therefore, this paper outlined the proposed stochastic approach in which tool error and growth rate uncertainty were explicitly considered. Computer simulation was used along with a process for continuously improving the characterization of each variable through a feedback loop. In order to minimize analysis time, the paper also outlined alternative methods to Monte Carlo, such as Importance Sampling. The approach has been successfully applied in field situations. It was shown that the approach can incorporate new information through repeat inspections or field excavations. 6 refs., 10 figs.

  14. Inspection qualification as a tool to risk based ET ISI of VVER type SG tubes

    Energy Technology Data Exchange (ETDEWEB)

    Horacek, L. [Nuclear Research Institue Rez plc (Czech Republic)

    2002-07-01

    A Pilot study on Eddy current inspection qualification of VVER 440 steam generator tubes, discussed in this paper, followed the ENIQ methodology principles and covered briefly the assumed scope of ET qualification, relevant elaborated qualification documents, known ISI limitations and a review of input information on component and defects determined for Eddy current inspection qualification of VVER 440 steam generator tubes. The information includes the fabrication of the test blocks with SG tube segments provided by intended defect simulations of realistic SCC type and basic data on the realistic SCC type defects manufacturing technology. Lessons learned from the development of manufacturing technology of SSC type of defects, regional blind tests, elaboration of the preliminary technical justification for Eddy current automated inspections, potential optimisation of inspection procedures, laboratory and practical open trials are summarised in the paper. The results of the Pilot study also especially in relation to POD curve being determined seem to be useful for practical operational ISI programme and Risk informed ISI decisions and the establishment of plugging criteria of VVER 440 and VVER 1000 type steam generator tubes. (orig.)

  15. Deposition uniformity inspection in IC wafer surface

    International Nuclear Information System (INIS)

    This paper focuses on the task of automatic visual inspection of color uniformity on the surface of integrated circuits (IC) wafers arising from the layering process. The oxide thickness uniformity within a given wafer with a desired target thickness is of great importance for modern semiconductor circuits with small oxide thickness. The non-uniform chemical vapor deposition (CVD) on a wafer surface will proceed to fail testing in Wafer Acceptance Test (WAT). Early detection of non-uniform deposition in a wafer surface can reduce material waste and improve production yields. The fastest and most low-priced inspection method is a machine vision-based inspection system. In this paper, the proposed visual inspection system is based on the color representations which were reflected from wafer surface. The regions of non-uniform deposition present different colors from the uniform background in a wafer surface. The proposed inspection technique first learns the color data via color space transformation from uniform deposition of normal wafer surfaces. The individual small region statistical comparison scheme then proceeds to the testing wafers. Experimental results show that the proposed method can effectively detect the non-uniform deposition regions on the wafer surface. The inspection time of the deposited wafers is quite compatible with the atmospheric pressure CVD time

  16. Corrosion mapping in ducts using the automated ultrasonic technique C-Scan - correlation with results given by pig inspection; Mapeamento de corrosao em dutos atraves da tecnica ultrassonica C-Scan

    Energy Technology Data Exchange (ETDEWEB)

    Feres Filho, Pedro; Moura, Nestor Carlos de [Physical Acoustics South America (PASA), Sao Paulo, SP (Brazil)

    2005-07-01

    In-service inspection has received diverse contributions from technologies and documents with the objective of maximizing equipment availability and minimizing inadequate repairs. Amongst the available technologies, there are the automated ultrasound tests, in the B and C-scan versions. This paper describes an evaluation methodology based on the correlation between the test techniques of instrumented electromagnetic PIG and automated ultrasound, both applied with the purpose of detecting and mapping areas with corrosion in pipes for oil transport. The main objective of the application of the C-scan methodology, in this case, was the measuring and detailing of the corroded area, thus providing an adequate maintenance plan through the substitution or installation of a double gutter. The result demonstrates the correlation between the measurements taken by the PIG and the sizing of the regions done using the C-scan method, consisting of the length, width and thickness values in the points affected by the corrosion. (author)

  17. NRU light water reflector inspections

    Energy Technology Data Exchange (ETDEWEB)

    Lumsden, R.H.; Hebert, H.; Zahn, N.; Simpson, N.W. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2011-07-01

    In 2009 May, the National Research Universal (NRU) calandria leaked. In the next year the calandria was inspected with six new techniques, repaired, and the repair inspected with four additional new techniques. The calandria is surrounded by a light water reflector vessel. Concerns that the same corrosion mechanism may have damaged the reflector vessel led to plans to inspect the full circumference of the reflector wall for corrosion damage, through a 64 mm diameter port, from 10 m away, while inspecting from the corroded surface. The ultrasonic technique is intended to produce a very fine inspection grid, through the corroded surface, using a very small probe body over the approximately 5 m{sup 2} to be inspected. The calandria vessel inspections were successfully performed, in a short time period, under difficult conditions. This paper will discuss Operating Experience (OPEX) from the 2009/2010 calandria wall inspections and industry dialogue that were applied to the Reflector Wall Inspection (RWI) project. Interaction with the CANDU Inspection Qualification Bureau (CIQB) on procedures, training plans, and mock-up training, led to improvements in how these activities were performed for the RWI project. Experience with shift turnover meetings led to improvements in how the inspection team captures lessons learned, trends issues, and eliminates reoccurring design and procedure problems. Experience with collected and analyzed data, inspection shift logs, and video captured from inspections and repairs, were used to improve inspection performance. Finally, OPEX from radiation/activation and the calibration process reduced dose through tool design and procedure changes. (author)

  18. Segmentation of Color Images Based on Different Segmentation Techniques

    OpenAIRE

    Purnashti Bhosale; Aniket Gokhale

    2013-01-01

    In this paper, we propose an Color image segmentation algorithm based on different segmentation techniques. We recognize the background objects such as the sky, ground, and trees etc based on the color and texture information using various methods of segmentation. The study of segmentation techniques by using different threshold methods such as global and local techniques and they are compared with one another so as to choose the best technique for threshold segmentation. Further segmentation...

  19. Autofluorescence based diagnostic techniques for oral cancer

    OpenAIRE

    Balasubramaniam, A. Murali; Sriraman, Rajkumari; Sindhuja, P; Mohideen, Khadijah; Parameswar, R. Arjun; Muhamed Haris, K. T.

    2015-01-01

    Oral cancer is one of the most common cancers worldwide. Despite of various advancements in the treatment modalities, oral cancer mortalities are more, particularly in developing countries like India. This is mainly due to the delay in diagnosis of oral cancer. Delay in diagnosis greatly reduces prognosis of the treatment and also cause increased morbidity and mortality rates. Early diagnosis plays a key role in effective management of oral cancer. A rapid diagnostic technique can greatly aid...

  20. Research on defects inspection of solder balls based on eddy current pulsed thermography.

    Science.gov (United States)

    Zhou, Xiuyun; Zhou, Jinlong; Tian, Guiyun; Wang, Yizhe

    2015-01-01

    In order to solve tiny defect detection for solder balls in high-density flip-chip, this paper proposed feasibility study on the effect of detectability as well as classification based on eddy current pulsed thermography (ECPT). Specifically, numerical analysis of 3D finite element inductive heat model is generated to investigate disturbance on the temperature field for different kind of defects such as cracks, voids, etc. The temperature variation between defective and non-defective solder balls is monitored for defects identification and classification. Finally, experimental study is carried on the diameter 1mm tiny solder balls by using ECPT and verify the efficacy of the technique. PMID:26473871

  1. Differential Laser Doppler based Non-Contact Sensor for Dimensional Inspection with Error Propagation Evaluation

    Directory of Open Access Journals (Sweden)

    Ketsaya Vacharanukul

    2006-06-01

    Full Text Available To achieve dynamic error compensation in CNC machine tools, a non-contactlaser probe capable of dimensional measurement of a workpiece while it is being machinedhas been developed and presented in this paper. The measurements are automatically fedback to the machine controller for intelligent error compensations. Based on a well resolvedlaser Doppler technique and real time data acquisition, the probe delivers a very promisingdimensional accuracy at few microns over a range of 100 mm. The developed opticalmeasuring apparatus employs a differential laser Doppler arrangement allowing acquisitionof information from the workpiece surface. In addition, the measurements are traceable tostandards of frequency allowing higher precision.

  2. Development of an in-service inspection technique for the intermediate heat exchanger tubes of the High-Temperature Engineering Test Reactor

    International Nuclear Information System (INIS)

    An experimental study is carried out to clarify the performance of an eddy current testing probe and probe-inserting equipment for the in-service inspection of the intermediate heat exchanger tubes of the High-Temperature Engineering Test Reactor. Artificial discontinuities are made with reference to the American Society of Mechanical Engineers standards for steam generator tubes in a light water reactor. It is confirmed that the probe can detect these discontinuities as well as smaller ones, such as a 0.5-mm-diam 100% through-wall hole and a 0.5-mm-wide groove, in a base-metal tube. For the welded joints, the back-excess weld metal is a main noise contributor, and a multiple-frequency method can remove the noise. The inspection performance, however, is lower. The probe-inserting equipment can smoothly insert and extract the probe. The winding of the cable causes a scattering in the probe traveling velocity values an a measurement error regarding the probe's location in the tube

  3. Path Based Mapping Technique for Robots

    Directory of Open Access Journals (Sweden)

    Amiraj Dhawan

    2013-05-01

    Full Text Available The purpose of this paper is to explore a new way of autonomous mapping. Current systems using perception techniques like LAZER or SONAR use probabilistic methods and have a drawback of allowing considerable uncertainty in the mapping process. Our approach is to break down the environment, specifically indoor, into reachable areas and objects, separated by boundaries, and identifying their shape, to render various navigable paths around them. This is a novel method to do away with uncertainties, as far as possible, at the cost of temporal efficiency. Also this system demands only minimum and cheap hardware, as it relies on only Infra-Red sensors to do the job.

  4. Speech recognition based on pattern recognition techniques

    Science.gov (United States)

    Rabiner, Lawrence R.

    1990-05-01

    Algorithms for speech recognition can be characterized broadly as pattern recognition approaches and acoustic phonetic approaches. To date, the greatest degree of success in speech recognition has been obtained using pattern recognition paradigms. The use of pattern recognition techniques were applied to the problems of isolated word (or discrete utterance) recognition, connected word recognition, and continuous speech recognition. It is shown that understanding (and consequently the resulting recognizer performance) is best to the simplest recognition tasks and is considerably less well developed for large scale recognition systems.

  5. Drum inspection robots: Application development

    International Nuclear Information System (INIS)

    Throughout the Department of Energy (DOE), drums containing mixed and low level stored waste are inspected, as mandated by the Resource Conservation and Recovery Act (RCRA) and other regulations. The inspections are intended to prevent leaks by finding corrosion long before the drums are breached. The DOE Office of Science and Technology (OST) has sponsored efforts towards the development of robotic drum inspectors. This emerging application for mobile and remote sensing has broad applicability for DOE and commercial waste storage areas. Three full scale robot prototypes have been under development, and another project has prototyped a novel technique to analyze robotically collected drum images. In general, the robots consist of a mobile, self-navigating base vehicle, outfitted with sensor packages so that rust and other corrosion cues can be automatically identified. They promise the potential to lower radiation dose and operator effort required, while improving diligence, consistency, and documentation

  6. User interface inspection methods a user-centered design method

    CERN Document Server

    Wilson, Chauncey

    2014-01-01

    User Interface Inspection Methods succinctly covers five inspection methods: heuristic evaluation, perspective-based user interface inspection, cognitive walkthrough, pluralistic walkthrough, and formal usability inspections. Heuristic evaluation is perhaps the best-known inspection method, requiring a group of evaluators to review a product against a set of general principles. The perspective-based user interface inspection is based on the principle that different perspectives will find different problems in a user interface. In the related persona-based inspection, colleagues assume the

  7. A color-based visualization technique for multielectrode spike trains.

    Science.gov (United States)

    Jurjut, Ovidiu F; Nikolić, Danko; Pipa, Gordon; Singer, Wolf; Metzler, Dirk; Mureşan, Raul C

    2009-12-01

    Multi electrode recordings of neuronal activity provide an overwhelming amount of data that is often difficult to analyze and interpret. Although various methods exist for treating multielectrode datasets quantitatively, there is a particularly prominent lack of techniques that enable a quick visual exploration of such datasets. Here, by using Kohonen self-organizing maps, we propose a simple technique that allows for the representation of multiple spike trains through a sequence of color-coded population activity vectors. When multiple color sequences are grouped according to a certain criterion, e.g., by stimulation condition or recording time, one can inspect an entire dataset visually and extract quickly information about the identity, stimulus-locking and temporal distribution of multi-neuron activity patterns. Color sequences can be computed on various time scales revealing different aspects of the temporal dynamics and can emphasize high-order correlation patterns that are not detectable with pairwise techniques. Furthermore, this technique is useful for determining the stability of neuronal responses during a recording session. Due to its simplicity and reliance on perceptual grouping, the method is useful for both quick on-line visualization of incoming data and for more detailed post hoc analyses. PMID:19846620

  8. Additive Manufacturing Infrared Inspection

    Science.gov (United States)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  9. A Survey Based on Opinion Classification Techniques.

    Directory of Open Access Journals (Sweden)

    Poongodi S

    2013-10-01

    Full Text Available The essential one is to collect the information as what the people think forever. Nowadays people can share everything in online Social network such as twitter, facebook. .People articulates their views and opinions regarding products and services. People can easily access and understand the opinions of others via web resources like as blog, review, and forum. These opinions are individual information which represents user’s opinions. The precise way for predicting opinions are to extract sentiments from the web, which could valuable for marketing research. Opinions are so vital that whenever need to make a decision before want to know others’ opinions. Opinion is not only important for a user but is also useful for an organization. This survey is about various methods and techniques used to classify the user opinions like as positive, negative.

  10. Comparison of Vibration-Based Damage Assessment Techniques

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Rytter, A.

    1995-01-01

    Three different vibration-based damage assessment techniques have been compared. One of the techniques uses the ratios between changes in experimentally and theoretically estimated natural frequencies, respectively, to locate a damage. The second technique relies on updating of a finite element...

  11. Key Point Based Data Analysis Technique

    Science.gov (United States)

    Yang, Su; Zhang, Yong

    In this paper, a new framework for data analysis based on the "key points" in data distribution is proposed. Here, the key points contain three types of data points: bridge points, border points, and skeleton points, where our main contribution is the bridge points. For each type of key points, we have developed the corresponding detection algorithm and tested its effectiveness with several synthetic data sets. Meanwhile, we further developed a new hierarchical clustering algorithm SPHC (Skeleton Point based Hierarchical Clustering) to demonstrate the possible applications of the key points acquired. Based on some real-world data sets, we experimentally show that SPHC performs better compared with several classical clustering algorithms including Complete-Link Hierarchical Clustering, Single-Link Hierarchical Clustering, KMeans, Ncut, and DBSCAN.

  12. An Automated Sorting System Based on Virtual Instrumentation Techniques

    Directory of Open Access Journals (Sweden)

    Rodica Holonec

    2008-07-01

    Full Text Available The application presented in this paper represents an experimental model and it refers to the implementing of an automated sorting system for pieces of same shape but different sizes and/or colors. The classification is made according to two features: the color and weight of these pieces. The system is a complex combination of NI Vision hardware and software tools, strain gauges transducers, signal conditioning connected to data acquisition boards, motion and control elements. The system is very useful for students to learn and experiment different virtual instrumentation techniques in order to be able to develop a large field of applications from inspection and process control to sorting and assembly

  13. Inspection program for U.S. research reactors

    International Nuclear Information System (INIS)

    This paper presents an established program for inspection of nuclear research reactors to ensure that systems and techniques are in accordance with regulatory requirements and to provide protection for the health and safety of the public. The inspection program, implemented from the time a facility gets licensed, remains in effect through operations, shutdown, decommissioning, and until the license is terminated. The program establishes inspection methodology for operating, safeguards, and decommissioning activities. Using a performance- based approach, inspectors focus their attention on activities important to safety. Inspection procedures allow the inspectors to assess facility safety and compliance to applicable requirements. A well designed inspection program is an integral part of the mechanism to ensure that the level of performance in the strategic areas of reactor safety, radiation safety, and safeguards is acceptable and provides adequate protection of public health and safety. (author)

  14. Activity Based Costing versus Traditional Technique

    OpenAIRE

    Dragomirescu Simona Elena; Solomon Daniela Cristina

    2011-01-01

    One of the current methods of management is Activity-Based Costing (ABC), method that allows the company to understand more clearly how and on what activity/product profit is achieved. In essence, the method involves identifying all specific activities of a product or service and distribution expenses to achieve them with greater accuracy than with traditional accounting methods. This involves not only costs determining closer to reality, but a better understanding of the factors that determi...

  15. An Authentication Technique Based on Classification

    Institute of Scientific and Technical Information of China (English)

    李钢; 杨杰

    2004-01-01

    We present a novel watermarking approach based on classification for authentication, in which a watermark is embedded into the host image. When the marked image is modified, the extracted watermark is also different to the original watermark, and different kinds of modification lead to different extracted watermarks. In this paper, different kinds of modification are considered as classes, and we used classification algorithm to recognize the modifications with high probability. Simulation results show that the proposed method is potential and effective.

  16. Survey of image-based representations and compression techniques

    OpenAIRE

    Shum, HY; Kang, SB; Chan, SC

    2003-01-01

    In this paper, we survey the techniques for image-based rendering (IBR) and for compressing image-based representations. Unlike traditional three-dimensional (3-D) computer graphics, in which 3-D geometry of the scene is known, IBR techniques render novel views directly from input images. IBR techniques can be classified into three categories according to how much geometric information is used: rendering without geometry, rendering with implicit geometry (i.e., correspondence), and rendering ...

  17. Performance of a tagged neutron inspection system (TNIS) based on portable sealed generators

    International Nuclear Information System (INIS)

    A portable sealed neutron generator has been modified to produce 14MeV tagged neutron beams with an embedded YAP:Ce scintillation detector. The system has been tested by detecting the coincident gamma-rays produced in the irradiation of a graphite sample by means of a standard NaI(Tl) scintillator. Time resolution of about δt=4-5ns (FWHM) has been measured. The sealed neutron tube has been operated up to 107neutron/s. Possible applications in non-destructive assays and future developments of the Tagged Neutron Inspection System concept are discussed

  18. Hospital Inspections

    Data.gov (United States)

    U.S. Department of Health & Human Services — Welcome to hospitalinspections.org, a website run by the Association of Health Care Journalists (AHCJ) that aims to make federal hospital inspection reports easier...

  19. Comparative study of Palito inspection and MFL Inspection

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Anne A. de; Miranda, Ivan Vicente Janvrot; Silva, Jose Augusto Pereira da [Pipeway Engenharia, Rio de Janeiro, RJ (Brazil); Guimaraes, Frederico S.; Magalhaes, Joao Alfredo P. [Minds at Work, Rio de Janeiro, RJ (Brazil); Sabino, Joao Marcos [Petroleo Brasileiro S.A. (PETROBRAS/UN-RN/CE), Natal, RN (Brazil). Unidade de Negocios Rio Grande do Norte e Ceara

    2009-07-01

    A 16 inches oil pipeline was surveyed with MFL and Palito pig in 2007. The MFL inspection was performed by Pipeway Engenharia while Palito inspection was performed by PETROBRAS. A comparison between the results of these two ILI inspections has been made to validate Palito Pig and to assess main characteristics and differences between the two techniques. The purpose of this paper is to detail the methodology applied to perform the comparison and to present a comparative study of results registered in the MFL and Palito inspections by Pipeway Engenharia, PETROBRAS/CENPES and CPTI/PUC-Rio. (author)

  20. On-site inspection: A brief overview and bibliography of techniques pertinent to assessing suspected nuclear test sites

    International Nuclear Information System (INIS)

    The purpose of this report is to provide a brief overview and bibliography of those techniques that may have application for the evaluation of a site to determine if a high energy release event is nuclear in nature. This effort is motivated by recognition of the changing world political climate and the perception that low yield and non-proliferation issues will grow in importance as countries become increasingly involved as signators to treaties that are intended to limit the development and testing of nuclear weapons. Along with an increasing interest in such issues is the awareness of the need to implement improved capabilities for treaty monitoring programs that must deal with assessing suspicious occurrences of high energy release events. In preparing this report, it is recognized that monitoring can take two main forms. The first involves the resolution of unidentified events detected by seismic and satellite National Technical Means. Events of an indeterminate nature could occur world-wide and could induce tension in neighboring countries. If an on-site measurement capability were available, a monitoring team could be sent to the suspected site of an event to take measurements that could confirm or disprove the occurrence of a clandestine nuclear test. The second monitoring form is the confirmation that a clandestine event is not masked by a declared event. For example, a large mining explosion could mask a decoupled nuclear explosion. On-site measurements before and during the test could confirm that a clandestine event did not occur and could provide assurance that the party carrying out the explosion is not taking advantage of clandestine testing opportunities. 48 refs

  1. FDI and Accommodation Using NN Based Techniques

    Science.gov (United States)

    Garcia, Ramon Ferreiro; de Miguel Catoira, Alberto; Sanz, Beatriz Ferreiro

    Massive application of dynamic backpropagation neural networks is used on closed loop control FDI (fault detection and isolation) tasks. The process dynamics is mapped by means of a trained backpropagation NN to be applied on residual generation. Process supervision is then applied to discriminate faults on process sensors, and process plant parameters. A rule based expert system is used to implement the decision making task and the corresponding solution in terms of faults accommodation and/or reconfiguration. Results show an efficient and robust FDI system which could be used as the core of an SCADA or alternatively as a complement supervision tool operating in parallel with the SCADA when applied on a heat exchanger.

  2. Development and application of proposed ASME Section XI Code changes for risk-based inspection of piping

    International Nuclear Information System (INIS)

    This synopsis has been written to describe a perspective on the development and application of ASME Section XI Code changes for risk-based inspection of piping. The content is specifically related to the use of risk-based technology for Inservice Inspection (ISI) of piping and efforts made to support the ASME Research/Westinghouse Owners Group/Millstone Unit 3 approach for use of this technology. The opinions contained herein may or may not reflect those of the ASME Codes and Standards Committees responsible for these activities. In order to take such a detailed technical subject and put it into an understandable format, the author has chosen to provide an analogy to simplify what is actually taking place. Risk-based technology in the ISI of piping can be likened to the process of making and using specifically ground prescription glasses to allow for better vision. It provides a process to develop and use these uniquely ground glasses that will dynamically focus on all the locations and obstacles within a plant's piping systems that could cause that plant to trip and fall; more importantly it identifies the locations where the fall could possibly hurt someone else. In this way, Nuclear Safety is being addressed

  3. NRF Based Nondestructive Inspection System for SNM by Using Laser-Compton-Backscattering Gamma-Rays

    Science.gov (United States)

    Ohgaki, H.; Omer, M.; Negm, H.; Daito, I.; Zen, H.; Kii, T.; Masuda, K.; Hori, T.; Hajima, R.; Hayakawa, T.; Shizuma, T.; Kando, M.

    2015-10-01

    A non-destructive inspection system for special nuclear materials (SNMs) hidden in a sea cargo has been developed. The system consists of a fast screening system using neutron generated by inertial electrostatic confinement (IEC) device and an isotope identification system using nuclear resonance fluorescence (NRF) measurements with laser Compton backscattering (LCS) gamma-rays has been developed. The neutron flux of 108 n/sec has been achieved by the IEC in static mode. We have developed a modified neutron reactor noise analysis method to detect fission neutron in a short time. The LCS gamma-rays has been generated by using a small racetrack microtoron accelerator and an intense sub-nano second laser colliding head-on to the electron beam. The gamma-ray flux has been achieved more than 105 photons/s. The NRF gamma-rays will be measured using LaBr3(Ce) scintillation detector array whose performance has been measured by NRF experiment of U-235 in HIGS facility. The whole inspection system has been designed to satisfy a demand from the sea port.

  4. Personnel neutron monitoring based on albedo technique

    International Nuclear Information System (INIS)

    This work deals with the study, design and test of a personal neutron monitor based on the detection of albedo neutrons from the body and its further relation to the incident flux. By this method, neutrons of energies below about 100 KeV can be efficiently detected, providing good information in the region where the biological effectiveness of neutron radiation starts to rise. The system consists of a pair of Thermoluminescent Detectors (6 LiF - 7 LiF) ∼ inside a polyethylene moderating body, in order to increase the sensitivity. The surface of the dosimeter facing away from the body is covered by a layer of a borated resin to assure appropriate shielding of incident low energy neutrons. The response of the dosimeter to monoenergetic neutrons from a 3 MeV Van de Graaff, to Am Be neutrons and to neutrons from a thermal column was investigated. The directional sensitivity, the effect of beam divergence was well as the effect of changes in dosimeter-to-body distances were also studied. (author)

  5. Inspection of disposal canisters components

    International Nuclear Information System (INIS)

    This report presents the inspection techniques of disposal canister components. Manufacturing methods and a description of the defects related to different manufacturing methods are described briefly. The defect types form a basis for the design of non-destructive testing because the defect types, which occur in the inspected components, affect to choice of inspection methods. The canister components are to nodular cast iron insert, steel lid, lid screw, metal gasket, copper tube with integrated or separate bottom, and copper lid. The inspection of copper material is challenging due to the anisotropic properties of the material and local changes in the grain size of the copper material. The cast iron insert has some acoustical material property variation (attenuation, velocity changes, scattering properties), which make the ultrasonic inspection demanding from calibration point of view. Mainly three different methods are used for inspection. Ultrasonic testing technique is used for inspection of volume, eddy current technique, for copper components only, and visual testing technique are used for inspection of the surface and near surface area

  6. Cronos, an advanced system for RCCA inspection

    International Nuclear Information System (INIS)

    The Rod Cluster Control Assembly (RCCA) is critical for the safe operation of nuclear power plants since its main function is to control neutron activity inside the core. These assemblies have a spider-shaped structure and are made up of a set of rods filled with a neutron absorbent. They are usually partially inserted in the fuel assemblies (normally only the lower part during normal operation) and may be completely inserted when necessary. The degradation mechanisms that may typically occur during the operation of the rod cluster control assemblies are as follows: - wear caused by friction of the rods against their guide structures; - increase in the diameter of the tips of the rods caused by irradiation-induced swelling of the absorbent. This increase in diameter causes deformation of the rod, which may generate cracks in the material of the rod and eventually hinder its insertion in the fuel assemblies. The RCCA's have traditionally been inspected with a view to verifying their correct status and guaranteeing their operability. Since the 1990's, Tecnatom has been performing eddy current inspections using systems based on different techniques (wrap-around, pancake and rotary probes). The new CRONOS inspection system (IS) developed by Tecnatom combines the eddy current (ET) and ultrasonic (UT) methods, incorporating the capacity to detect and characterise all the possible degradations that affect the RCCA's. At present Tecnatom has a mechanical system applicable to RCCA's for 17x17 fuel assemblies and is developing a second unit for 16x16 assemblies. Development of the CRONOS IS began in 2011 and the system has been used successfully in three inspections at Spanish NPPs (2 at Vandellos 2 and 1 at Asco 1) and one inspection in China (Ling Ao 2 NPP). The control cluster rods inspected are made of AISI304 or 316 stainless steel, with a chrome or nitride surface treatment, and have a nominal outer diameter of 9.68 mm and a thickness of between 0

  7. Huffman-based code compression techniques for embedded processors

    KAUST Repository

    Bonny, Mohamed Talal

    2010-09-01

    The size of embedded software is increasing at a rapid pace. It is often challenging and time consuming to fit an amount of required software functionality within a given hardware resource budget. Code compression is a means to alleviate the problem by providing substantial savings in terms of code size. In this article we introduce a novel and efficient hardware-supported compression technique that is based on Huffman Coding. Our technique reduces the size of the generated decoding table, which takes a large portion of the memory. It combines our previous techniques, Instruction Splitting Technique and Instruction Re-encoding Technique into new one called Combined Compression Technique to improve the final compression ratio by taking advantage of both previous techniques. The instruction Splitting Technique is instruction set architecture (ISA)-independent. It splits the instructions into portions of varying size (called patterns) before Huffman coding is applied. This technique improves the final compression ratio by more than 20% compared to other known schemes based on Huffman Coding. The average compression ratios achieved using this technique are 48% and 50% for ARM and MIPS, respectively. The Instruction Re-encoding Technique is ISA-dependent. It investigates the benefits of reencoding unused bits (we call them reencodable bits) in the instruction format for a specific application to improve the compression ratio. Reencoding those bits can reduce the size of decoding tables by up to 40%. Using this technique, we improve the final compression ratios in comparison to the first technique to 46% and 45% for ARM and MIPS, respectively (including all overhead that incurs). The Combined Compression Technique improves the compression ratio to 45% and 42% for ARM and MIPS, respectively. In our compression technique, we have conducted evaluations using a representative set of applications and we have applied each technique to two major embedded processor architectures

  8. Information-Driven Inspections

    International Nuclear Information System (INIS)

    New uranium enrichment capacity is being built worldwide in response to perceived shortfalls in future supply. To meet increasing safeguards responsibilities with limited resources, the nonproliferation community is exploring next-generation concepts to increase the effectiveness and efficiency of safeguards, such as advanced technologies to enable unattended monitoring of nuclear material. These include attribute measurement technologies, data authentication tools, and transmission and security methods. However, there are several conceptual issues with how such data would be used to improve the ability of a safeguards inspectorate such as the International Atomic Energy Agency (IAEA) to reach better safeguards conclusions regarding the activities of a State. The IAEA is pursuing the implementation of information-driven safeguards, whereby all available sources of information are used to make the application of safeguards more effective and efficient. Data from continuous, unattended monitoring systems can be used to optimize on-site inspection scheduling and activities at declared facilities, resulting in fewer, better inspections. Such information-driven inspections are the logical evolution of inspection planning - making use of all available information to enhance scheduled and randomized inspections. Data collection and analysis approaches for unattended monitoring systems can be designed to protect sensitive information while enabling information-driven inspections. A number of such inspections within a predetermined range could reduce inspection frequency while providing an equal or greater level of deterrence against illicit activity, all while meeting operator and technology holder requirements and reducing inspector and operator burden. Three options for using unattended monitoring data to determine an information-driven inspection schedule are to (1) send all unattended monitoring data off-site, which will require advances in data analysis techniques to

  9. Information-Driven Inspections

    Energy Technology Data Exchange (ETDEWEB)

    Laughter, Mark D [ORNL; Whitaker, J Michael [ORNL; Lockwood, Dunbar [U.S. Department of Energy, NNSA

    2010-01-01

    New uranium enrichment capacity is being built worldwide in response to perceived shortfalls in future supply. To meet increasing safeguards responsibilities with limited resources, the nonproliferation community is exploring next-generation concepts to increase the effectiveness and efficiency of safeguards, such as advanced technologies to enable unattended monitoring of nuclear material. These include attribute measurement technologies, data authentication tools, and transmission and security methods. However, there are several conceptual issues with how such data would be used to improve the ability of a safeguards inspectorate such as the International Atomic Energy Agency (IAEA) to reach better safeguards conclusions regarding the activities of a State. The IAEA is pursuing the implementation of information-driven safeguards, whereby all available sources of information are used to make the application of safeguards more effective and efficient. Data from continuous, unattended monitoring systems can be used to optimize on-site inspection scheduling and activities at declared facilities, resulting in fewer, better inspections. Such information-driven inspections are the logical evolution of inspection planning - making use of all available information to enhance scheduled and randomized inspections. Data collection and analysis approaches for unattended monitoring systems can be designed to protect sensitive information while enabling information-driven inspections. A number of such inspections within a predetermined range could reduce inspection frequency while providing an equal or greater level of deterrence against illicit activity, all while meeting operator and technology holder requirements and reducing inspector and operator burden. Three options for using unattended monitoring data to determine an information-driven inspection schedule are to (1) send all unattended monitoring data off-site, which will require advances in data analysis techniques to

  10. Earthquake Analysis of Structure by Base Isolation Technique in SAP

    OpenAIRE

    T. Subramani; J. Jothi

    2014-01-01

    This paper presents an overview of the present state of base isolation techniques with special emphasis and a brief on other techniques developed world over for mitigating earthquake forces on the structures. The dynamic analysis procedure for isolated structures is briefly explained. The provisions of FEMA 450 for base isolated structures are highlighted. The effects of base isolation on structures located on soft soils and near active faults are given in brief. Simple case s...

  11. Array-based techniques for fingerprinting medicinal herbs

    Directory of Open Access Journals (Sweden)

    Xue Charlie

    2011-05-01

    Full Text Available Abstract Poor quality control of medicinal herbs has led to instances of toxicity, poisoning and even deaths. The fundamental step in quality control of herbal medicine is accurate identification of herbs. Array-based techniques have recently been adapted to authenticate or identify herbal plants. This article reviews the current array-based techniques, eg oligonucleotides microarrays, gene-based probe microarrays, Suppression Subtractive Hybridization (SSH-based arrays, Diversity Array Technology (DArT and Subtracted Diversity Array (SDA. We further compare these techniques according to important parameters such as markers, polymorphism rates, restriction enzymes and sample type. The applicability of the array-based methods for fingerprinting depends on the availability of genomics and genetics of the species to be fingerprinted. For the species with few genome sequence information but high polymorphism rates, SDA techniques are particularly recommended because they require less labour and lower material cost.

  12. Radiation Protection and Nuclear Safety Regulatory Inspection: a happy marriage?

    International Nuclear Information System (INIS)

    As the subsidiary of the Belgian Federal Agency for Nuclear Control (FANC), Bel V performs the regulatory inspections and safety assessments in nuclear installations, according to the Belgian Royal Decree of July 20. 2001. This Royal Decree is not meant to give a recipe on how to perform inspections and therefore requires interpretation. This paper presents the inspection techniques and practices applied by the Bel V inspectors in order to comply with the spirit of the Royal Decree, using the available resources. AT Bel V the inspections are based on the sampling principle in combination with the experience feedback process. Inspections occur frequently, typically once a week. Concerning documentation, the inspector looks at a sample of documents, the licensee knows he has to produce high-quality documents that have to be correct and as a consequence the licensee has to set internal independent review. If the inspector were to look at every document, the licensee may consider the inspector as a mere reviewer as he checks every document and the global quality of the documentation may decrease. In order to optimize the inspections, the inspection reports circulate among all the members of Bel V (inspectors and experts). Everyone is invited to comment these reports if he deems that the inspector should be made aware of an important issue, that the inspector should take a closer look at a certain aspect,.... These remarks help the inspector to prepare the next inspection. The slides of the presentation have been added at the end of the paper

  13. Computer-vision-based registration techniques for augmented reality

    Science.gov (United States)

    Hoff, William A.; Nguyen, Khoi; Lyon, Torsten

    1996-10-01

    Augmented reality is a term used to describe systems in which computer-generated information is superimposed on top of the real world; for example, through the use of a see- through head-mounted display. A human user of such a system could still see and interact with the real world, but have valuable additional information, such as descriptions of important features or instructions for performing physical tasks, superimposed on the world. For example, the computer could identify and overlay them with graphic outlines, labels, and schematics. The graphics are registered to the real-world objects and appear to be 'painted' onto those objects. Augmented reality systems can be used to make productivity aids for tasks such as inspection, manufacturing, and navigation. One of the most critical requirements for augmented reality is to recognize and locate real-world objects with respect to the person's head. Accurate registration is necessary in order to overlay graphics accurately on top of the real-world objects. At the Colorado School of Mines, we have developed a prototype augmented reality system that uses head-mounted cameras and computer vision techniques to accurately register the head to the scene. The current system locates and tracks a set of pre-placed passive fiducial targets placed on the real-world objects. The system computes the pose of the objects and displays graphics overlays using a see-through head-mounted display. This paper describes the architecture of the system and outlines the computer vision techniques used.

  14. Knowledge-based inspection:modelling complex processes with the integrated Safeguards Modelling Method (iSMM)

    International Nuclear Information System (INIS)

    Increased level of complexity in almost every discipline and operation today raises the demand for knowledge in order to successfully run an organization whether to generate profit or to attain a non-profit mission. Traditional way of transferring knowledge to information systems rich in data structures and complex algorithms continue to hinder the ability to swiftly turnover concepts into operations. Diagrammatic modelling commonly applied in engineering in order to represent concepts or reality remains to be an excellent way of converging knowledge from domain experts. The nuclear verification domain represents ever more a matter which has great importance to the World safety and security. Demand for knowledge about nuclear processes and verification activities used to offset potential misuse of nuclear technology will intensify with the growth of the subject technology. This Doctoral thesis contributes with a model-based approach for representing complex process such as nuclear inspections. The work presented contributes to other domains characterized with knowledge intensive and complex processes. Based on characteristics of a complex process a conceptual framework was established as the theoretical basis for creating a number of modelling languages to represent the domain. The integrated Safeguards Modelling Method (iSMM) is formalized through an integrated meta-model. The diagrammatic modelling languages represent the verification domain and relevant nuclear verification aspects. Such a meta-model conceptualizes the relation between practices of process management, knowledge management and domain specific verification principles. This fusion is considered as necessary in order to create quality processes. The study also extends the formalization achieved through a meta-model by contributing with a formalization language based on Pattern Theory. Through the use of graphical and mathematical constructs of the theory, process structures are formalized enhancing

  15. Surface Inspection Of Automotive Bodies By Reflective Computer Vision

    Science.gov (United States)

    Hung, Y. Y.; Jin, G. C.; Tang, S. H.

    1988-12-01

    A simple but practical optical technique for automated surface inspection of car bodies is presented. The method which is based on light reflection is applicable to inspecting specularly reflective surfaces such as painted car bodies. A structured light signal consists of linear grating is imaged by a video camera via the surface to be inspected. With this arrangement, the surface being inspected acts as a mirror. Presence of surface flaws causes the grating to be locally perturbed. The grating-image is digitized and analyzed by a computer. Several algorithms are developed which automatically identifies the surface flaws by analyzing the perturbation in the grating-image. The technique allows surface flaws to be quantified in terms of slope deviation or depth variation. The sensitivity of the technique is very high permitting minute flaws to be detected. In the paper the theory of the technique will be presented together with experimental validation. The technique possesses numerous practical features such as requiring no special surface preparation, allowing evaluation in place, requiring minimum environmental safeguards, allowing rapid testing and evaluation, providing reliable and quantitative results, and it can be automated. Therefore the technique has clearly exhibited a great potential for being developed into a production-line inspection tool.

  16. Proof of pipeline strength based on measurements of inspection pigs; Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen

    Energy Technology Data Exchange (ETDEWEB)

    De la Camp, H.J.; Feser, G.; Hofmann, A.; Wolf, B.; Schmidt, H. [TUeV Sueddeutschland Bau und Betrieb GmbH, Muenchen (Germany); Herforth, H.E.; Juengling, K.H.; Schmidt, W. [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg

    2002-01-01

    The report is aimed at collecting and documenting the state of the art and the extensive know how of experts and pipeline operators with regard to judging the structural integrity of pipelines. In order to assess the actual mechanical strength of pipelines based on measurement results obtained by inspection pigs, guidance is given for future processing, which eventually can be used as a basis for an industry standard. A literature study of the commercially available types of inspection pigs describes and synoptically lists the respective pros and cons. In essence the report comprises besides check lists of operating data for the pipeline and the pig runs mainly the evaluation of defects and respective calculating procedures. Included are recommendations regarding maintenance planning, verification of defects as well as repetition of pig runs. (orig.) [German] Ziel des Berichtes ist die Erfassung und Dokumentation zum derzeitigen Stand der Technik und des vorhandenen umfangreichen Know-how von Sachverstaendigen und Pipelinebetreibern auf dem Gebiet der sicherheitstechnischen Beurteilung von Pipelines. Fuer den Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen wurde ein Leitfaden als Basis fuer die zukuenftige Vorgehensweise erstellt, der eventuell die Grundlage eines normativen Regelwerkes bilden kann. In einer Literaturstudie wurden die auf dem Markt befindlichen Pruefmolchtypen zusammenfassend beschrieben und ihre Vor- und Nachteile tabellarisch gegenuebergestellt und bewertet. Neben der Erstellung von Checklisten fuer notwendige Daten zum Betrieb der Pipeline und der Molchlaeufe bildet die Fehlerbewertung mit entsprechenden Berechnungsverfahren den Hauptteil dieses Berichtes. Hinweise zur Instandhaltungsplanung (Fehlerverifikation und Molchlaufwiederholung) werden gegeben. (orig.)

  17. Automatic noncontact ultrasonic inspection technique

    International Nuclear Information System (INIS)

    A system for EMAT, which generates ultrasound by electro-magnectic forces and performs nondestructive testing in noncontact, was established. By linking it with a 3 axis scanning system and a data acquisition and processing system the automation of EMAT testing was attempted. A EMAT sensor was fabricated and the directivity pattern of it was measured. To be suitable automation ir has a transmitter and a receiver in one case and the main beam direction of it can be controlled by the frequency of driving signal. A program which controls the EMAT system, the 3 axis scanner and the data acquisition and processing system was developed. It also processes acquired data and displays the processing results. IBM-PC/AT compatible PC was used as main controller and the stratage of the program is emulation of real devices on the PC monitor. To provide the performance of the established EMAT system, two aluminium blocks containing artificial flaws and a welded aluminium block were tested. The result of the tests were satisfactory.

  18. Inspection scheme

    International Nuclear Information System (INIS)

    As part of the Danish RERTR Program, three fuel elements with LEU U3O8-Al fuel and three fuel elements with LEU U3Si2-Al fuel were manufactured by NUKEM for irradiation testing in the DR-3 reactor at the Risoe National Laboratory in Denmark. The inspection scheme for the elements with U3O8-Al fuel is presented here as an illustration only. The inspection scheme for the elements with U3Si2-Al fuel was very similar. In this example, all document numbers, drawing numbers, and form numbers have been deleted or replaced with a generic identification. (author)

  19. Fusion Based Neutron Sources for Security Applications: Neutron Techniques

    OpenAIRE

    Albright, S.; Seviour, Rebecca

    2014-01-01

    The current reliance on X-Rays and intelligence for na- tional security is insufficient to combat the current risks of smuggling and terrorism seen on an international level. There are a range of neutron based security techniques which have the potential to dramatically improve national security. Neutron techniques can be broadly grouped into neutron in/neutron out and neutron in/photon out tech- niques. The use of accelerator based fusion devices will potentially enable to wide spread applic...

  20. Base Oils Biodegradability Prediction with Data Mining Techniques

    OpenAIRE

    Malika Trabelsi; Saloua Saidane; Sihem Ben Abdelmelek

    2010-01-01

    In this paper, we apply various data mining techniques including continuous numeric and discrete classification prediction models of base oils biodegradability, with emphasis on improving prediction accuracy. The results show that highly biodegradable oils can be better predicted through numeric models. In contrast, classification models did not uncover a similar dichotomy. With the exception of Memory Based Reasoning and Decision Trees, tested classification techniques achieved high classifi...

  1. Advanced ultrasonic inspection system for the ID-inspection of reactor pressure vessels of BWRs

    International Nuclear Information System (INIS)

    A newly-developed, modular ultrasonic examination system has been developed by Siemens for the ID inspection of BWR RPV'S. It is based on the phased-array technique with hybrid probes using the latest in manipulator and control equipment technology to allow the often hard-to-access weld areas of older reactor pressure vessels in US BWR plants to be examined within a very short time and with minimal radiation exposure of the examination personnel. New NRC stipulations requiring almost complete ultrasonic examination of all RPV welds can be fully satisfied using this system for the ID inspection of all longitudinal and circumferential welds above the jet pump baffle plate

  2. The detection of bulk explosives using nuclear-based techniques

    Energy Technology Data Exchange (ETDEWEB)

    Morgado, R.E.; Gozani, T.; Seher, C.C.

    1988-01-01

    In 1986 we presented a rationale for the detection of bulk explosives based on nuclear techniques that addressed the requirements of civil aviation security in the airport environment. Since then, efforts have intensified to implement a system based on thermal neutron activation (TNA), with new work developing in fast neutron and energetic photon reactions. In this paper we will describe these techniques and present new results from laboratory and airport testing. Based on preliminary results, we contended in our earlier paper that nuclear-based techniques did provide sufficiently penetrating probes and distinguishable detectable reaction products to achieve the FAA operational goals; new data have supported this contention. The status of nuclear-based techniques for the detection of bulk explosives presently under investigation by the US Federal Aviation Administration (FAA) is reviewed. These include thermal neutron activation (TNA), fast neutron activation (FNA), the associated particle technique, nuclear resonance absorption, and photoneutron activation. The results of comprehensive airport testing of the TNA system performed during 1987-88 are summarized. From a technical point of view, nuclear-based techniques now represent the most comprehensive and feasible approach for meeting the operational criteria of detection, false alarms, and throughput. 9 refs., 5 figs., 2 tabs.

  3. Application of glyph-based techniques for multivariate engineering visualization

    Science.gov (United States)

    Glazar, Vladimir; Marunic, Gordana; Percic, Marko; Butkovic, Zlatko

    2016-01-01

    This article presents a review of glyph-based techniques for engineering visualization as well as practical application for the multivariate visualization process. Two glyph techniques, Chernoff faces and star glyphs, uncommonly used in engineering practice, are described, applied to the selected data set, run through the chosen optimization methods and user evaluated. As an example of how these techniques function, a set of data for the optimization of a heat exchanger with a microchannel coil is adopted for visualization. The results acquired by the chosen visualization techniques are related to the results of optimization carried out by the response surface method and compared with the results of user evaluation. Based on the data set from engineering research and practice, the advantages and disadvantages of these techniques for engineering visualization are identified and discussed.

  4. Rapid analysis of steels using laser-based techniques

    International Nuclear Information System (INIS)

    Based on the data obtained by this study, we conclude that laser-based techniques can be used to provide at least semi-quantitative information about the elemental composition of molten steel. Of the two techniques investigated here, the Sample-Only method appears preferable to the LIBS (laser-induced breakdown spectroscopy) method because of its superior analytical performance. In addition, the Sample-Only method would probably be easier to incorporate into a steel plant environment. However, before either technique can be applied to steel monitoring, additional research is needed

  5. Model-based POD study of manual ultrasound inspection and sensitivity analysis using metamodel

    Science.gov (United States)

    Ribay, Guillemette; Artusi, Xavier; Jenson, Frédéric; Reece, Christopher; Lhuillier, Pierre-Emile

    2016-02-01

    The reliability of NDE can be quantified by using the Probability of Detection (POD) approach. Former studies have shown the potential of the model-assisted POD (MAPOD) approach to replace expensive experimental determination of POD curves. In this paper, we make use of CIVA software to determine POD curves for a manual ultrasonic inspection of a heavy component, for which a whole experimental POD campaign was not available. The influential parameters were determined by expert analysis. The semi-analytical models used in CIVA for wave propagation and beam-defect interaction have been validated in the range of variation of the influential parameters by comparison with finite element modelling (Athena). The POD curves are computed for « hit/miss » and « â versus a » analysis. The verification of Berens hypothesis is evaluated by statistical tools. A sensitivity study is performed to measure the relative influence of parameters on the defect response amplitude variance, using the Sobol sensitivity index. A meta-model is also built to reduce computing cost and enhance the precision of estimated index.

  6. INSPECTION OF CNC MADE PARTS

    OpenAIRE

    Prof. Yogesh R. Falak*; Rahul Patil; Kalpesh Bhagat,

    2015-01-01

    Inspection is an important process of manufacturing system. It is means of rejecting error parts and assuring good quality parts. The advantages of technological innovation in inspection equipment helped to overcome the problems associated with traditional approaches. Such means that used of labour intensive method increase in total manufacturing time and production cost. Advanced sensor and inspection technologies, interfaced with computer based systems to automate the operations...

  7. Dual view x-ray inspection system for foreign objects detection in canned food

    Science.gov (United States)

    Lu, Zhiwen; Peng, Ningsong

    2013-04-01

    X-ray inspection technique for foreign objects in food products can determine and mark the presence of contaminants within the product by using image processing and pattern recognition technique on the X-ray transmission images. This paper presents the dual view X-ray inspection technique for foreign objects in food jar via analyzing the weak points of the traditional single view X-ray inspection technique. In addition, a prototype with the new technique is developed in accordance with glass splinters detection within the food jar (glass jar especially) which is a typical tickler. Some algorithms such as: adaptive image segmentation based on contour tracking, nonlinear arctan function transform and etc., are applied to improve image quality and achieve effective inspection results. The false recognition rate is effectively reduced and the detection sensitivity is highly enhanced. Finally the actual test results of this prototype are given.

  8. Data Mining and Neural Network Techniques in Case Based System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper first puts forward a case-based system framework basedon data mining techniques. Then the paper examines the possibility of using neural n etworks as a method of retrieval in such a case-based system. In this system we propose data mining algorithms to discover case knowledge and other algorithms.

  9. An Agent Communication Framework Based on XML and SOAP Technique

    Institute of Scientific and Technical Information of China (English)

    李晓瑜

    2009-01-01

    This thesis introducing XML technology and SOAP technology,present an agent communication fi-amework based on XML and SOAP technique,and analyze the principle,architecture,function and benefit of it. At the end, based on KQML communication primitive lan- guages.

  10. Power system stabilizers based on modern control techniques

    Energy Technology Data Exchange (ETDEWEB)

    Malik, O.P.; Chen, G.P.; Zhang, Y.; El-Metwally, K. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering

    1994-12-31

    Developments in digital technology have made it feasible to develop and implement improved controllers based on sophisticated control techniques. Power system stabilizers based on adaptive control, fuzzy logic and artificial networks are being developed. Each of these control techniques possesses unique features and strengths. In this paper, the relative performance of power systems stabilizers based on adaptive control, fuzzy logic and neural network, both in simulation studies and real time tests on a physical model of a power system, is presented and compared to that of a fixed parameter conventional power system stabilizer. (author) 16 refs., 45 figs., 3 tabs.

  11. Simulation-based optimization parametric optimization techniques and reinforcement learning

    CERN Document Server

    Gosavi, Abhijit

    2003-01-01

    Simulation-Based Optimization: Parametric Optimization Techniques and Reinforcement Learning introduces the evolving area of simulation-based optimization. The book's objective is two-fold: (1) It examines the mathematical governing principles of simulation-based optimization, thereby providing the reader with the ability to model relevant real-life problems using these techniques. (2) It outlines the computational technology underlying these methods. Taken together these two aspects demonstrate that the mathematical and computational methods discussed in this book do work. Broadly speaking, the book has two parts: (1) parametric (static) optimization and (2) control (dynamic) optimization. Some of the book's special features are: *An accessible introduction to reinforcement learning and parametric-optimization techniques. *A step-by-step description of several algorithms of simulation-based optimization. *A clear and simple introduction to the methodology of neural networks. *A gentle introduction to converg...

  12. Safety System functional inspections

    International Nuclear Information System (INIS)

    The basic purpose of Safety System Functional Inspections (SSFI) is to carry out an impartial and independent assessment of previously selected safety systems, in order to determine whether they have been installed, tested, operated and managed in accordance with the original Design Bases and with the applicable regulatory requirements, codes and standards, that is, their Licensing Bases. These functional inspections are performed within the framework established by the Quality Assurance Programmes of electric utility owners, and in accordance with specifically prepared procedures previously approved for each power plant. These SSFIs verify, for safety systems and their support systems (eg HVAC systems, etc), the operational availability of inspected systems of components by researching and determining whether there have been generic or programmed deficiencies in the course of Operation, that will prevent the systems from adequately performing the functions for which they were originally designed. PSA and IPE results are used as the basis for selecting the systems that should undergo functional inspections. As a consequence of these SSFIs, final reports will be prepared, summarizing actions taken at the plants and contemplating discrepancies or deviations detected during inspection. The necessary corrective actions for these discrepancies will be indicated in either the design documentation or the Operation and Maintenance Procedures. (Author)

  13. A Hough Transform based Technique for Text Segmentation

    CERN Document Server

    Saha, Satadal; Nasipuri, Mita; Basu, Dipak Kr

    2010-01-01

    Text segmentation is an inherent part of an OCR system irrespective of the domain of application of it. The OCR system contains a segmentation module where the text lines, words and ultimately the characters must be segmented properly for its successful recognition. The present work implements a Hough transform based technique for line and word segmentation from digitized images. The proposed technique is applied not only on the document image dataset but also on dataset for business card reader system and license plate recognition system. For standardization of the performance of the system the technique is also applied on public domain dataset published in the website by CMATER, Jadavpur University. The document images consist of multi-script printed and hand written text lines with variety in script and line spacing in single document image. The technique performs quite satisfactorily when applied on mobile camera captured business card images with low resolution. The usefulness of the technique is verifie...

  14. Face Recognition Approach Based on Wavelet - Curvelet Technique

    Directory of Open Access Journals (Sweden)

    Muzhir Shaban Al-Ani

    2012-04-01

    Full Text Available In this paper, a novel face recognition approach based on wavelet-curvelet technique, is proposed. This algorithm based on the similarities embedded in the images, That utilize the wavelet-curvelet technique to extract facial features. The implemented technique can overcome on the other mathematical image analysis approaches. This approaches may suffered from the potential for a high dimensional feature space, Therefore it aims to reduce the dimensionality that reduce the required computational power and memory size. Then the Nearest Mean Classifier (NMC is adopted to recognize different faces. In this work, three major experiments were done. two face databases (MAFD & ORL, and higher recognition rate is obtained by the implementation of this techniques.

  15. Risk Informed Decision Making by a Public Safety Regulatory Authority in Canada: A Case Study involving Risk Based Scheduling of Periodic Inspections

    International Nuclear Information System (INIS)

    The Technical Standards and Safety Authority (TSSA) is an independent, not-for-profit organization that administers and enforces public safety laws associated with Amusement Devices, Elevating Devices, Boilers and Pressure Vessels, Fuels, Operating Engineers, and Upholstery and Stuffed Articles, under Ontario's Technical Standards and Safety Act through an administrative agreement with the province of Ontario in Canada. TSSA has introduced a risk informed decision-making framework across a wide variety of safety activities in each of the regulated sectors. One of these activities involves periodic engineering inspections of facilities and equipment during operation to ensure that the devices continue to operate safely. The inspection process reviews how the equipment and technology are being used, operated and maintained, and identifies any non-compliance to safety codes and regulations. TSSA has designed and implemented risk-based inspection scheduling models across most of its industry sectors to ensure that devices that present the highest risk to the public are inspected more often while low-risk units are assigned longer inspection cycles. The model development and implementation was carried out in three stages: 1) Concept development based on identification of risk factors representing the devices and equipment, human-device interaction, and location; 2) Model design using a semi-quantitative risk assessment approach; and 3) Implementation, including automated scheduling, monitoring, and measurement. This presentation will describe the three stages with specific reference to the model developed for the elevating devices sector. (authors)

  16. Apparatus for inspecting a group of containers and method of using same

    Science.gov (United States)

    Lee, Jr., James H.; Salton, Jonathan R.; Spletzer, Barry L.

    2012-02-28

    An apparatus and method for inspecting a plurality of containers are provided. Each container has an outer surface for housing at least one material therein. The techniques provided involve at least one inspection vehicle and at least one detector. Each inspection vehicle has a plurality of wheels for movably positioning about the plurality of containers. The wheels may have at least one magnet for selectively adhering to the outer surface of at least one of the containers whereby the inspection vehicle traverses the container(s). The detector is positionable proximate at least one of the containers. The detector may be deployable from the inspection vehicle to a position adjacent the container(s). The detector has at least one sensor for measuring at least one characteristic of the plurality of containers. At least one base station may be provided for communicating with the inspection vehicle(s) and/or detector(s).

  17. Intramuscular injection technique: an evidence-based approach.

    Science.gov (United States)

    Ogston-Tuck, Sherri

    2014-09-30

    Intramuscular injections require a thorough and meticulous approach to patient assessment and injection technique. This article, the second in a series of two, reviews the evidence base to inform safer practice and to consider the evidence for nursing practice in this area. A framework for safe practice is included, identifying important points for safe technique, patient care and clinical decision making. It also highlights the ongoing debate in selection of intramuscular injection sites, predominately the ventrogluteal and dorsogluteal muscles. PMID:25249123

  18. A Hough Transform based Technique for Text Segmentation

    OpenAIRE

    Saha, Satadal; Basu, Subhadip; Nasipuri, Mita; Basu, Dipak Kr.

    2010-01-01

    Text segmentation is an inherent part of an OCR system irrespective of the domain of application of it. The OCR system contains a segmentation module where the text lines, words and ultimately the characters must be segmented properly for its successful recognition. The present work implements a Hough transform based technique for line and word segmentation from digitized images. The proposed technique is applied not only on the document image dataset but also on dataset for business card rea...

  19. Combining Speedup techniques based on Landmarks and Containers

    Directory of Open Access Journals (Sweden)

    R. KALPANA

    2010-09-01

    Full Text Available The Dijkstra’s algorithm [1] , which is applied in many real world problems like mobile routing, road maps, railway networks, etc,. is used to find the shortest path between source and destination. There are many techniques available to speedup the algorithm while guaranteeing the optimality of the solution. The main focus of the work is to implement landmark technique and Containers separately and compare the results with random graphs and planar graphs. The combined speedup technique which is based on landmarks and containers were also experimented with random graphs and planar graphs to improvethe speedup of the shortest path queries.

  20. Finding Within Cluster Dense Regions Using Distance Based Technique

    OpenAIRE

    Wesam Ashour; Motaz Murtaja

    2012-01-01

    One of the main categories in Data Clustering is density based clustering. Density based clustering techniques like DBSCAN are attractive because they can find arbitrary shaped clusters along with noisy outlier. The main weakness of the traditional density based algorithms like DBSCAN is clustering the different density level data sets. DBSCAN calculations done according to given parameters applied to all points in a data set, while densities of the data set clusters may be totally different....

  1. An innovative design for using flexible printed coils for magnetostrictive-based longitudinal guided wave sensors in steel strand inspection

    International Nuclear Information System (INIS)

    Magnetostrictive sensors (MsSs) that can excite and receive guided waves are commonly used in detecting defects that may occur in cables and strands for supporting heavy structures. A conventional MsS has a hard sensing coil that is wound onto a bobbin with electric wires to generate the necessary dynamic magnetic field to excite the desired guided waves. This tailor-made hard coil is usually bulky and is not flexible enough to fit steel strands of various sizes. The conventional MsS also cannot be mounted to any steel strand that does not have a free end to allow the bobbin to pass through the structure of the tested strand. Such inflexibilities limit the use of conventional MsSs in practical situations. To solve these limitations, an innovative type of coil, called a flexible printed coil (FPC), which is made out of flexible printed film, has been designed to replace the inflexible hard coil. The flexible structure of the FPC ensures that the new MsS can be easily installed on and removed from steel strands with different diameters and without free ends. Moreover, the FPC-based MsS can be wrapped into multiple layers due to its thin and flexible design. Although multi-layer FPC creates a minor asymmetry in the dynamic magnetic field, the results of finite element analysis and experiments confirm that the longitudinal guided waves excited by a FPC-based MsS are comparable to those excited by a conventional hard coil MsS. No significant reduction in defect inspection performance was found; in fact, further advantages were identified when using the FPC-based MsS. When acting as the transmitter, the innovative FPC-based MsS can cover a longer inspection length of strand. When acting as the receiver, the FPC-based MsS is more sensitive to smaller defects that are impossible to detect using a hard coil MsS. Hence, the multi-layer FPC-based MsS has great potential for replacing the conventional hard coil MsS because of its convenient installation, and ease of fitting to

  2. Runtime Monitoring Technique to handle Tautology based SQL Injection Attacks

    Directory of Open Access Journals (Sweden)

    Ramya Dharam

    2015-05-01

    Full Text Available Software systems, like web applications, are often used to provide reliable online services such as banking, shopping, social networking, etc., to users. The increasing use of such systems has led to a high need for assuring confidentiality, integrity, and availability of user data. SQL Injection Attacks (SQLIAs is one of the major security threats to web applications. It allows attackers to get unauthorized access to the back-end database consisting of confidential user information. In this paper we present and evaluate a Runtime Monitoring Technique to detect and prevent tautology based SQLIAs in web applications. Our technique monitors the behavior of the application during its post- deployment to identify all the tautology based SQLIAs. A framework called Runtime Monitoring Framework, that implements our technique, is used in the development of runtime monitors. The framework uses two pre-deployment testing techniques, such as basis-path and data-flow to identify a minimal set of all legal/valid execution paths of the application. Runtime monitors are then developed and integrated to perform runtime monitoring of the application, during its post-deployment for the identified valid/legal execution paths. For evaluation we targeted a subject application with a large number of both legitimate inputs and illegitimate tautology based inputs, and measured the performance of the proposed technique. The results of our study show that runtime monitor developed for the application was successfully able to detect all the tautology based attacks without generating any false positives.

  3. Laser-based direct-write techniques for cell printing

    Science.gov (United States)

    Schiele, Nathan R; Corr, David T; Huang, Yong; Raof, Nurazhani Abdul; Xie, Yubing; Chrisey, Douglas B

    2016-01-01

    Fabrication of cellular constructs with spatial control of cell location (±5 μm) is essential to the advancement of a wide range of applications including tissue engineering, stem cell and cancer research. Precise cell placement, especially of multiple cell types in co- or multi-cultures and in three dimensions, can enable research possibilities otherwise impossible, such as the cell-by-cell assembly of complex cellular constructs. Laser-based direct writing, a printing technique first utilized in electronics applications, has been adapted to transfer living cells and other biological materials (e.g., enzymes, proteins and bioceramics). Many different cell types have been printed using laser-based direct writing, and this technique offers significant improvements when compared to conventional cell patterning techniques. The predominance of work to date has not been in application of the technique, but rather focused on demonstrating the ability of direct writing to pattern living cells, in a spatially precise manner, while maintaining cellular viability. This paper reviews laser-based additive direct-write techniques for cell printing, and the various cell types successfully laser direct-written that have applications in tissue engineering, stem cell and cancer research are highlighted. A particular focus is paid to process dynamics modeling and process-induced cell injury during laser-based cell direct writing. PMID:20814088

  4. Mobile X-ray inspection of light weight materials

    Energy Technology Data Exchange (ETDEWEB)

    Ewert, Uwe; Redmer, Bernhard; Raedel, Christoph; Osterloh, Kurt [Federal Inst. for Materials Research and Testing (BAM), Berlin (Germany); Schnars, Ulf; Henrich, Rudolf; Schimmelmann, Olaf [Airbus, Bremen/Stade (Germany); Bavendiek, Klaus; Jahn, Mirko [YXLON International, Hamburg (Germany)

    2008-07-01

    Digital detectors such as phosphor imaging plates (IP) and digital detector arrays (DDA) allow radiographic inspection with higher efficiency and improved image quality in comparison to the classic film technique. Mobile X-ray flash tubes are used routinely for veterinarian and security applications. New high sensitive IPs and DDAs enable to apply them for inspection of light materials with low X-ray attenuation as in aluminium, plastics and composites. A versatile computed tomography (CT) system was developed for in situ inspection of large aircraft components under production conditions. A gate based planar computed tomograph was developed and tested for inspection of integrity of the stringer incorporation. Successful test trials were performed to prove the detection rate of cracks in embedded stringers. Honey comb structures of aircrafts have to be inspected for water inclusions during in-service inspections. Thermography is a powerful method for in house inspections when variations in temperature caused e.g. by sunshine can be excluded. A new X-ray diaphragm was developed for mobile back scatter measurements of large components. This method is insensitive to heat alterations in the field and thus can be applied also outdoors. (orig.)

  5. Mobile X-ray inspection of light weight materials

    International Nuclear Information System (INIS)

    Digital detectors such as phosphor imaging plates (IP) and digital detector arrays (DDA) allow radiographic inspection with higher efficiency and improved image quality in comparison to the classic film technique. Mobile X-ray flash tubes are used routinely for veterinarian and security applications. New high sensitive IPs and DDAs enable to apply them for inspection of light materials with low X-ray attenuation as in aluminium, plastics and composites. A versatile computed tomography (CT) system was developed for in situ inspection of large aircraft components under production conditions. A gate based planar computed tomograph was developed and tested for inspection of integrity of the stringer incorporation. Successful test trials were performed to prove the detection rate of cracks in embedded stringers. Honey comb structures of aircrafts have to be inspected for water inclusions during in-service inspections. Thermography is a powerful method for in house inspections when variations in temperature caused e.g. by sunshine can be excluded. A new X-ray diaphragm was developed for mobile back scatter measurements of large components. This method is insensitive to heat alterations in the field and thus can be applied also outdoors. (orig.)

  6. PCA Based Rapid and Real Time Face Recognition Technique

    Directory of Open Access Journals (Sweden)

    T R Chandrashekar

    2013-12-01

    Full Text Available Economical and efficient that is used in various applications is face Biometric which has been a popular form biometric system. Face recognition system is being a topic of research for last few decades. Several techniques are proposed to improve the performance of face recognition system. Accuracy is tested against intensity, distance from camera, and pose variance. Multiple face recognition is another subtopic which is under research now a day. Speed at which the technique works is a parameter under consideration to evaluate a technique. As an example a support vector machine performs really well for face recognition but the computational efficiency degrades significantly with increase in number of classes. Eigen Face technique produces quality features for face recognition but the accuracy is proved to be comparatively less to many other techniques. With increase in use of core processors in personal computers and application demanding speed in processing and multiple face detection and recognition system (for example an entry detection system in shopping mall or an industry, demand for such systems are cumulative as there is a need for automated systems worldwide. In this paper we propose a novel system of face recognition developed with C# .Net that can detect multiple faces and can recognize the faces parallel by utilizing the system resources and the core processors. The system is built around Haar Cascade based face detection and PCA based face recognition system with C#.Net. Parallel library designed for .Net is used to aide to high speed detection and recognition of the real time faces. Analysis of the performance of the proposed technique with some of the conventional techniques reveals that the proposed technique is not only accurate, but also is fast in comparison to other techniques.

  7. Use of combined ultrasonic techniques in testing of undercladding flaws from the outside

    International Nuclear Information System (INIS)

    The scope of different methodologies and terms used in ultrasonic inspections is very wide. On the other hand, almost all the techniques are based on the measurement of the same parameters. In this study the possibilities to combine the advantages of different techniques are surveyed in order to establish an effective inspection technique producing reliable results. (orig.) (14 refs., 21 figs., 1 tab.)

  8. A multi-criteria decision model to determine inspection intervals of condition monitoring based on delay time analysis

    International Nuclear Information System (INIS)

    In periodic monitoring, the main problem is determining the inspection interval of condition monitoring. For this problem, the decision variable is represented by the time of next inspection of condition monitoring. There are several studies that deal with prescribing inspection intervals. But only a few of these allow the decision maker to observe simultaneously more than one aspect. This does not accord with the natural tendency of the decision maker who desires to see the decision problem from a broader perspective, by having different viewpoints or dimensions of choices. Therefore, the main objective of this paper is to propose a decision model, which can simultaneously determine inspection intervals for condition monitoring regarding the failure behavior of equipment to be inspected, features of maintainability and decision maker preferences about cost and downtime

  9. Enabling inspection solutions for future mask technologies through the development of massively parallel E-Beam inspection

    Science.gov (United States)

    Malloy, Matt; Thiel, Brad; Bunday, Benjamin D.; Wurm, Stefan; Jindal, Vibhu; Mukhtar, Maseeh; Quoi, Kathy; Kemen, Thomas; Zeidler, Dirk; Eberle, Anna Lena; Garbowski, Tomasz; Dellemann, Gregor; Peters, Jan Hendrik

    2015-09-01

    The new device architectures and materials being introduced for sub-10nm manufacturing, combined with the complexity of multiple patterning and the need for improved hotspot detection strategies, have pushed current wafer inspection technologies to their limits. In parallel, gaps in mask inspection capability are growing as new generations of mask technologies are developed to support these sub-10nm wafer manufacturing requirements. In particular, the challenges associated with nanoimprint and extreme ultraviolet (EUV) mask inspection require new strategies that enable fast inspection at high sensitivity. The tradeoffs between sensitivity and throughput for optical and e-beam inspection are well understood. Optical inspection offers the highest throughput and is the current workhorse of the industry for both wafer and mask inspection. E-beam inspection offers the highest sensitivity but has historically lacked the throughput required for widespread adoption in the manufacturing environment. It is unlikely that continued incremental improvements to either technology will meet tomorrow's requirements, and therefore a new inspection technology approach is required; one that combines the high-throughput performance of optical with the high-sensitivity capabilities of e-beam inspection. To support the industry in meeting these challenges SUNY Poly SEMATECH has evaluated disruptive technologies that can meet the requirements for high volume manufacturing (HVM), for both the wafer fab [1] and the mask shop. Highspeed massively parallel e-beam defect inspection has been identified as the leading candidate for addressing the key gaps limiting today's patterned defect inspection techniques. As of late 2014 SUNY Poly SEMATECH completed a review, system analysis, and proof of concept evaluation of multiple e-beam technologies for defect inspection. A champion approach has been identified based on a multibeam technology from Carl Zeiss. This paper includes a discussion on the

  10. Ultrasonic inspection methodology

    International Nuclear Information System (INIS)

    Steam generator tubes are known to be susceptible to stress corrosion cracking (SCC). Primary water SCC (PWSCC) and more recently secondary water SCC (SWSCC) have been observed in some Belgian plants. To help dealing with these problems, Laborelec developed an ultrasonic (UT) inspection system. It has been used for the last two years on a sampling basis in several plants. The field and laboratory measurements confirmed the advantage of using UT for the early detection of small circumferential cracks while an excellent correlation was demonstrated between eddy current RPC and UT for axial PWSCC. In conclusion: The latest in-service inspections demonstrated an average measurement cycle of 50 to 60 seconds per tube including the manipulator displacement from tube to tube. A sample of about 250 tubes with axial cracks was measured on-site with the eddy current RPC technique and the new UT system. All the UT measured lengths were within ± 1.5 mm of the RPC results. The same results were obtained from the inspection of the tubes repaired with the nickel process (Doel 3). Some indications of circumferential secondary side stress corrosion cracking were recently observed. A comparison with the eddy current rotating pancake coil confirmed the improved detectability of the UT system. The field and laboratory results obtained with this UT inspection system demonstrated the advantage of applying the ultrasonic technique for the detection and sizing of small volume cracks like SCC. Also, the small focal spot of the UT beam provided a clear advantage for the detection of circumferential PWSCC in the presence of multiple axial cracks. With an average rate dose to 60 tubes per hour for the top of the tubesheet area, this UT system can be considered as an industrial tool for the inspection of steam generator tubes

  11. Mask pattern recovery by level set method based inverse inspection technology (IIT) and its application on defect auto disposition

    Science.gov (United States)

    Park, Jin-Hyung; Chung, Paul D. H.; Jeon, Chan-Uk; Cho, Han Ku; Pang, Linyong; Peng, Danping; Tolani, Vikram; Cecil, Tom; Kim, David; Baik, KiHo

    2009-10-01

    At the most advanced technology nodes, such as 32nm and 22nm, aggressive OPC and Sub-Resolution Assist Features (SRAFs) are required. However, their use results in significantly increased mask complexity, making mask defect disposition more challenging than ever. This paper describes how mask patterns can first be recovered from the inspection images by applying patented algorithms using Level Set Methods. The mask pattern recovery step is then followed by aerial/wafer image simulation, the results of which can be plugged into an automated mask defect disposition system based on aerial/wafer image. The disposition criteria are primarily based on wafer-plane CD variance. The system also connects to a post-OPC lithography verification tool that can provide gauges and CD specs, thereby enabling them to be used in mask defect disposition as well. Results on both programmed defects and production defects collected at Samsung mask shop are presented to show the accuracy and consistency of using the Level Set Methods and aerial/wafer image based automated mask disposition.

  12. Generic data base for security equipment and its utility in the safeguards inspection process. Final report 8151-79-FR-16

    International Nuclear Information System (INIS)

    This report contains material presented at the Nuclear Regulatory Commission (NRC) conference of regional inspectors in Atlanta, Georgia, on January 17, 1979. It describes the contents of the generic data base for security equipment, which was developed by SRI for NRC under a Sandia Laboratories' subcontract, and examines its potential utility in the process of inspection of NRC-licensed facilities

  13. Wavelet transformation based watermarking technique for human electrocardiogram (ECG).

    Science.gov (United States)

    Engin, Mehmet; Cidam, Oğuz; Engin, Erkan Zeki

    2005-12-01

    Nowadays, watermarking has become a technology of choice for a broad range of multimedia copyright protection applications. Watermarks have also been used to embed prespecified data in biomedical signals. Thus, the watermarked biomedical signals being transmitted through communication are resistant to some attacks. This paper investigates discrete wavelet transform based watermarking technique for signal integrity verification in an Electrocardiogram (ECG) coming from four ECG classes for monitoring application of cardiovascular diseases. The proposed technique is evaluated under different noisy conditions for different wavelet functions. Daubechies (db2) wavelet function based technique performs better than those of Biorthogonal (bior5.5) wavelet function. For the beat-to-beat applications, all performance results belonging to four ECG classes are highly moderate. PMID:16235811

  14. Remote ultrasonic inspection of Magnox reactor standpipes

    International Nuclear Information System (INIS)

    Although Magnox reactor standpipes are not subjected to routine in-service examination, it is occassionally necessary to inspect them for potential problems. Checks on wall thickness, weld integrity and the condition of inaccessible surfaces are made using remote ultrasonic immersion techniques from the bore. Special manipulators with rugged, inflatable seals allow the inspection zones to be completely flooded. The immersion technique has proved a reliable and safe method of inspection. Several of these applications are described. (author)

  15. Periodic inspections of the primary system

    International Nuclear Information System (INIS)

    An impression is given of the inspection techniques, preparations and background for periodic examinations of the primary system of the Dodewaard Nuclear Reactor over the past 10 years. Unfortunately reliable integral inspection techniques to enable 'listening-in' to developing faults, are not yet available. Until they are, inspections will continue to be executed from a distance using different continuous methods, often under water and with a shortage of space and in the presence of ionising radiations. (C.F.)

  16. Planning Annual Shutdown Inspection for BFB Boiler

    OpenAIRE

    Sorsa, Tatu

    2014-01-01

    The goal of this thesis was to create an illustrative guidebook of annual inspection planning for BFB boiler to help power plant operator when planning of annual inspection is topical. This thesis was made for Andritz Oy and it is based on inspection reports and experiences of BFB boiler’s maintenance and inspection staff. In this thesis it is shown how to plan an annual inspection for BFB boiler and thesis gives good tools and hints for operator to manage inspection from the beginning ...

  17. "Ayeli": Centering Technique Based on Cherokee Spiritual Traditions.

    Science.gov (United States)

    Garrett, Michael Tlanusta; Garrett, J. T.

    2002-01-01

    Presents a centering technique called "Ayeli," based on Cherokee spiritual traditions as a way of incorporating spirituality into counseling by helping clients identify where they are in their journey, where they want to be, and how they can get there. Relevant Native cultural traditions and meanings are explored. (Contains 25 references.) (GCP)

  18. Modal Analysis Based on the Random Decrement Technique

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Brincker, Rune

    1998-01-01

    This article describes the work carried out within the project: Modal Analysis Based on the Random Decrement Technique - Application to Civil Engineering Structures. The project is part of the research programme: Dynamics of Structures sponsored by the Danish Technical Research Counsil. The planned...

  19. Fixtureless geometric inspection of nonrigid parts using "generalized numerical inspection fixture"

    Science.gov (United States)

    Radvar Esfahlan, Hassan

    Free-form nonrigid parts form the substance of today's automotive and aerospace industries. These parts have different shapes in free state due to their dimensional and geometric variations, gravity and residual strains. For the geometric inspection of such compliant parts, special inspection fixtures, in combination with coordinate measuring systems (CMM) and/or optical data acquisition devices (scanners) are used. This inevitably causes additional costs and delays that result in a lack of competitiveness in the industry. The goal of this thesis is to facilitate the dimensional and geometrical inspection of flexible components from a point cloud without using a jig or secondary conformation operation. More specifically, we aim to develop a methodology to localize and quantify the profile defects in the case of thin shells which are typical to the aerospace and automotive industries. The presented methodology is based on the fact that the interpoint geodesic distance between any two points of a shape remains unchangeable during an isometric deformation. This study elaborates on the theory and general methods for the metrology of nonrigid parts. We have developed a Generalized Numerical Inspection Fixture (GNIF), a robust methodology which merges existing technologies in metric and computational geometry, nonlinear dimensionality reduction techniques, and finite element methods to introduce a general approach to the fixtureless geometrical inspection of nonrigid parts.

  20. Case-based reasoning diagnostic technique based on multi-attribute similarity

    Energy Technology Data Exchange (ETDEWEB)

    Makoto, Takahashi [Tohoku University, Miyagi (Japan); Akio, Gofuku [Okayama University, Okayamaa (Japan)

    2014-08-15

    Case-based diagnostic technique has been developed based on the multi-attribute similarity. Specific feature of the developed system is to use multiple attributes of process signals for similarity evaluation to retrieve a similar case stored in a case base. The present technique has been applied to the measurement data from Monju with some simulated anomalies. The results of numerical experiments showed that the present technique can be utilizes as one of the methods for a hybrid-type diagnosis system.

  1. The Real-Time Image Processing Technique Based on DSP

    Institute of Scientific and Technical Information of China (English)

    QI Chang; CHEN Yue-hua; HUANG Tian-shu

    2005-01-01

    This paper proposes a novel real-time image processing technique based on digital singnal processor (DSP). At the aspect of wavelet transform(WT) algorithm, the technique uses algorithm of second generation wavelet transform-lifting scheme WT that has low calculation complexity property for the 2-D image data processing. Since the processing effect of lifting scheme WT for 1-D data is better than the effect of it for 2-D data obviously, this paper proposes a reformative processing method: Transform 2-D image data to 1-D data sequence by linearization method, then process the 1-D data sequence by algorithm of lifting scheme WT. The method changes the image convolution mode,which based on the cross filtering of rows and columns. At the aspect of hardware realization, the technique optimizes the program structure of DSP to exert the operation power with the in-chip memorizer of DSP. The experiment results show that the real-time image processing technique proposed in this paper can meet the real-time requirement of video-image transmitting in the video surveillance system of electric power. So the technique is a feasible and efficient DSP solution.

  2. Video Multiple Watermarking Technique Based on Image Interlacing Using DWT

    Science.gov (United States)

    Ibrahim, Mohamed M.; Abdel Kader, Neamat S.; Zorkany, M.

    2014-01-01

    Digital watermarking is one of the important techniques to secure digital media files in the domains of data authentication and copyright protection. In the nonblind watermarking systems, the need of the original host file in the watermark recovery operation makes an overhead over the system resources, doubles memory capacity, and doubles communications bandwidth. In this paper, a robust video multiple watermarking technique is proposed to solve this problem. This technique is based on image interlacing. In this technique, three-level discrete wavelet transform (DWT) is used as a watermark embedding/extracting domain, Arnold transform is used as a watermark encryption/decryption method, and different types of media (gray image, color image, and video) are used as watermarks. The robustness of this technique is tested by applying different types of attacks such as: geometric, noising, format-compression, and image-processing attacks. The simulation results show the effectiveness and good performance of the proposed technique in saving system resources, memory capacity, and communications bandwidth. PMID:25587570

  3. Experiments on Adaptive Techniques for Host-Based Intrusion Detection

    International Nuclear Information System (INIS)

    This research explores four experiments of adaptive host-based intrusion detection (ID) techniques in an attempt to develop systems that can detect novel exploits. The technique considered to have the most potential is adaptive critic designs (ACDs) because of their utilization of reinforcement learning, which allows learning exploits that are difficult to pinpoint in sensor data. Preliminary results of ID using an ACD, an Elman recurrent neural network, and a statistical anomaly detection technique demonstrate an ability to learn to distinguish between clean and exploit data. We used the Solaris Basic Security Module (BSM) as a data source and performed considerable preprocessing on the raw data. A detection approach called generalized signature-based ID is recommended as a middle ground between signature-based ID, which has an inability to detect novel exploits, and anomaly detection, which detects too many events including events that are not exploits. The primary results of the ID experiments demonstrate the use of custom data for generalized signature-based intrusion detection and the ability of neural network-based systems to learn in this application environment

  4. An Observed Voting System Based On Biometric Technique

    Directory of Open Access Journals (Sweden)

    B. Devikiruba

    2015-08-01

    Full Text Available ABSTRACT This article describes a computational framework which can run almost on every computer connected to an IP based network to study biometric techniques. This paper discusses with a system protecting confidential information puts strong security demands on the identification. Biometry provides us with a user-friendly method for this identification and is becoming a competitor for current identification mechanisms. The experimentation section focuses on biometric verification specifically based on fingerprints. This article should be read as a warning to those thinking of using methods of identification without first examine the technical opportunities for compromising mechanisms and the associated legal consequences. The development is based on the java language that easily improves software packages that is useful to test new control techniques.

  5. Knowledge based systems advanced concepts, techniques and applications

    CERN Document Server

    1997-01-01

    The field of knowledge-based systems (KBS) has expanded enormously during the last years, and many important techniques and tools are currently available. Applications of KBS range from medicine to engineering and aerospace.This book provides a selected set of state-of-the-art contributions that present advanced techniques, tools and applications. These contributions have been prepared by a group of eminent researchers and professionals in the field.The theoretical topics covered include: knowledge acquisition, machine learning, genetic algorithms, knowledge management and processing under unc

  6. Proposing a Wiki-Based Technique for Collaborative Essay Writing

    Directory of Open Access Journals (Sweden)

    Mabel Ortiz Navarrete

    2014-10-01

    Full Text Available This paper aims at proposing a technique for students learning English as a foreign language when they collaboratively write an argumentative essay in a wiki environment. A wiki environment and collaborative work play an important role within the academic writing task. Nevertheless, an appropriate and systematic work assignment is required in order to make use of both. In this paper the proposed technique when writing a collaborative essay mainly attempts to provide the most effective way to enhance equal participation among group members by taking as a base computer mediated collaboration. Within this context, the students’ role is clearly defined and individual and collaborative tasks are explained.

  7. Hardware-based image processing for high-speed inspection of grains

    Science.gov (United States)

    A high-speed, low-cost, image-based sorting device was developed to detect and separate grains with slight color differences and small defects on grains The device directly combines a complementary metal–oxide–semiconductor (CMOS) color image sensor with a field-programmable gate array (FPGA) which...

  8. Nondestructive inspection for internal defects of rail based on photoacoustic elastography

    Science.gov (United States)

    Sun, Mingjian; Fu, Ying; Liu, Ting; Cheng, Xingzhen; Leng, Guanji; Feng, Naizhang

    2015-11-01

    Laser ultrasonic technique is used for the nondestructive testing technology of surface damage, but ignores the density variation in the sample. Photoacoustic elastography is adopted to obtain more rail information (such as the internal defects, the variation of sample's interior density) of the sample by collecting Rayleigh wave on rail surface and shear wave within the rail. In this paper, it is proved that the internal defects and the variation of density can be detected by photoacoustic elastography, using finite element analysis (FEA). We first use FEA to simulate the ultrasound excitation on the steel material surface excited by the laser source. Two cases of sample are modeled and analyzed, one is with defects of different depth and the other is with different density. Then, an isotropic model using ANSYS is employed and shear wave propagation is modeled. The preliminary results successfully recapitulate the trend of the change of shear wave's velocities, which shows that the defects can enhance the amplitude of shear wave. In addition, the velocities of shear wave would increase when the density of the sample enlarges. Results from computer simulations demonstrate the effectiveness of photoacoustic elastography with application to quantitative analysis for the structures of sample.

  9. Oil palm fresh fruit bunch ripeness classification based on rule- based expert system of ROI image processing technique results

    International Nuclear Information System (INIS)

    There is a processing need for a fast, easy and accurate classification system for oil palm fruit ripeness. Such a system will be invaluable to farmers and plantation managers who need to sell their oil palm fresh fruit bunch (FFB) for the mill as this will avoid disputes. In this paper,a new approach was developed under the name of expert rules-based systembased on the image processing techniques results of thethree different oil palm FFB region of interests (ROIs), namely; ROI1 (300x300 pixels), ROI2 (50x50 pixels) and ROI3 (100x100 pixels). The results show that the best rule-based ROIs for statistical colour feature extraction with k-nearest neighbors (KNN) classifier at 94% were chosen as well as the ROIs that indicated results higher than the rule-based outcome, such as the ROIs of statistical colour feature extraction with artificial neural network (ANN) classifier at 94%, were selected for further FFB ripeness inspection system

  10. Statistics and Machine Learning based Outlier Detection Techniques for Exoplanets

    Science.gov (United States)

    Goel, Amit; Montgomery, Michele

    2015-08-01

    Architectures of planetary systems are observable snapshots in time that can indicate formation and dynamic evolution of planets. The observable key parameters that we consider are planetary mass and orbital period. If planet masses are significantly less than their host star masses, then Keplerian Motion is defined as P^2 = a^3 where P is the orbital period in units of years and a is the orbital period in units of Astronomical Units (AU). Keplerian motion works on small scales such as the size of the Solar System but not on large scales such as the size of the Milky Way Galaxy. In this work, for confirmed exoplanets of known stellar mass, planetary mass, orbital period, and stellar age, we analyze Keplerian motion of systems based on stellar age to seek if Keplerian motion has an age dependency and to identify outliers. For detecting outliers, we apply several techniques based on statistical and machine learning methods such as probabilistic, linear, and proximity based models. In probabilistic and statistical models of outliers, the parameters of a closed form probability distributions are learned in order to detect the outliers. Linear models use regression analysis based techniques for detecting outliers. Proximity based models use distance based algorithms such as k-nearest neighbour, clustering algorithms such as k-means, or density based algorithms such as kernel density estimation. In this work, we will use unsupervised learning algorithms with only the proximity based models. In addition, we explore the relative strengths and weaknesses of the various techniques by validating the outliers. The validation criteria for the outliers is if the ratio of planetary mass to stellar mass is less than 0.001. In this work, we present our statistical analysis of the outliers thus detected.

  11. Sampling-Based Sweep Planning to Exploit Local Planarity in the Inspection of Complex 3d Structures

    OpenAIRE

    Englot, Brendan J.; Hover, Franz S.

    2012-01-01

    We present a hybrid algorithm that plans feasible paths for 100% sensor coverage of complex 3D structures. The structures to be inspected are segmented to isolate planar areas, and back-and-forth sweep paths are generated to view as much of these planar areas as possible while avoiding collision. A randomized planning procedure fills in the remaining gaps in coverage. The problem of selecting an order to traverse the elements of the inspection is solved by reduction to the traveling salesman ...

  12. Modelling in Optimal Inspection and Repair

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Rackwitz, R.; Faber, M.H.;

    1991-01-01

    A model for reliability based optimal inspection and repair strategies is described. The total expected costs in the lifetime is minimized with the number of inspections, the inspection times and efforts, the repair crack size limit and a design parameter as optimization variables. The equivalenc...

  13. Guided-wave tomography imaging plate defects by laser-based ultrasonic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jun Pil; Lim, Ju Young; Cho, Youn Ho [School of Mechanical Engineering, Pusan National University, Pusan (Korea, Republic of)

    2014-12-15

    Contact-guided-wave tests are impractical for investigating specimens with limited accessibility and rough surfaces or complex geometric features. A non-contact setup with a laser-ultrasonic transmitter and receiver is quite attractive for guided-wave inspection. In the present work, we developed a non-contact guided-wave tomography technique using the laser-ultrasonic technique in a plate. A method for Lamb-wave generation and detection in an aluminum plate with a pulsed laser-ultrasonic transmitter and Michelson-interferometer receiver was developed. The defect shape and area in the images obtained using laser scanning, showed good agreement with the actual defect. The proposed approach can be used as a non-contact online inspection and monitoring technique.

  14. Robotic inspection of fiber reinforced composites using phased array UT

    Science.gov (United States)

    Stetson, Jeffrey T.; De Odorico, Walter

    2014-02-01

    Ultrasound is the current NDE method of choice to inspect large fiber reinforced airframe structures. Over the last 15 years Cartesian based scanning machines using conventional ultrasound techniques have been employed by all airframe OEMs and their top tier suppliers to perform these inspections. Technical advances in both computing power and commercially available, multi-axis robots now facilitate a new generation of scanning machines. These machines use multiple end effector tools taking full advantage of phased array ultrasound technologies yielding substantial improvements in inspection quality and productivity. This paper outlines the general architecture for these new robotic scanning systems as well as details the variety of ultrasonic techniques available for use with them including advances such as wide area phased array scanning and sound field adaptation for non-flat, non-parallel surfaces.

  15. An Efficient Image Compression Technique Based on Arithmetic Coding

    Directory of Open Access Journals (Sweden)

    Prof. Rajendra Kumar Patel

    2012-12-01

    Full Text Available The rapid growth of digital imaging applications, including desktop publishing, multimedia, teleconferencing, and high visual definition has increased the need for effective and standardized image compression techniques. Digital Images play a very important role for describing the detailed information. The key obstacle for many applications is the vast amount of data required to represent a digital image directly. The various processes of digitizing the images to obtain it in the best quality for the more clear and accurate information leads to the requirement of more storage space and better storage and accessing mechanism in the form of hardware or software. In this paper we concentrate mainly on the above flaw so that we reduce the space with best quality image compression. State-ofthe-art techniques can compress typical images from 1/10 to 1/50 their uncompressed size without visibly affecting image quality. From our study I observe that there is a need of good image compression technique which provides better reduction technique in terms of storage and quality. Arithmetic coding is the best way to reducing encoding data. So in this paper we propose arithmetic coding with walsh transformation based image compression technique which is an efficient way of reduction

  16. Inspection focus technology of space tridimensional mapping camera based on astigmatic method

    Science.gov (United States)

    Wang, Zhi; Zhang, Liping

    2010-10-01

    The CCD plane of the space tridimensional mapping camera will be deviated from the focal plane(including the CCD plane deviated due to camera focal length changed), under the condition of space environment and vibration, impact when satellite is launching, image resolution ratio will be descended because defocusing. For tridimensional mapping camera, principal point position and focal length variation of the camera affect positioning accuracy of ground target, conventional solution is under the condition of vacuum and focusing range, calibrate the position of CCD plane with code of photoelectric encoder, when the camera defocusing in orbit, the magnitude and direction of defocusing amount are obtained by photoelectric encoder, then the focusing mechanism driven by step motor to compensate defocusing amount of the CCD plane. For tridimensional mapping camera, under the condition of space environment and vibration, impact when satellite is launching, if the camera focal length changes, above focusing method has been meaningless. Thus, the measuring and focusing method was put forward based on astigmation, a quadrant detector was adopted to measure the astigmation caused by the deviation of the CCD plane, refer to calibrated relation between the CCD plane poison and the asrigmation, the deviation vector of the CCD plane can be obtained. This method includes all factors caused deviation of the CCD plane, experimental results show that the focusing resolution of mapping camera focusing mechanism based on astigmatic method can reach 0.25 μm.

  17. Finding Within Cluster Dense Regions Using Distance Based Technique

    Directory of Open Access Journals (Sweden)

    Wesam Ashour

    2012-03-01

    Full Text Available One of the main categories in Data Clustering is density based clustering. Density based clustering techniques like DBSCAN are attractive because they can find arbitrary shaped clusters along with noisy outlier. The main weakness of the traditional density based algorithms like DBSCAN is clustering the different density level data sets. DBSCAN calculations done according to given parameters applied to all points in a data set, while densities of the data set clusters may be totally different. The proposed algorithm overcomes this weakness of the traditional density based algorithms. The algorithm starts with partitioning the data within a cluster to units based on a user parameter and compute the density for each unit separately. Consequently, the algorithm compares the results and merges neighboring units with closer approximate density values to become a new cluster. The experimental results of the simulation show that the proposed algorithm gives good results in finding clusters for different density cluster data set.

  18. Eddy current inspection methodology

    International Nuclear Information System (INIS)

    World-wide operating experience with nuclear pressurized water reactors shows that most steam generators show evidence of major degradation phenomena. Laborelec has designed several automated inspection systems using eddy current (bobbin coil, pancake coils and rotating coil) and ultrasound techniques. The bobbin coil is mostly used as a fast and global detection method while dedicated sensors, like the rotating pancake coil, are applied for an improved defect characterization. Experience has demonstrated that significant advantages in accuracy, reliability and cost are intimately related to the automation process. In conclusion: The concept of a multipurpose inspection system satisfies the safety goal and the utility requirements for reliability, accuracy and lower costs. An optimum was reached by equipment modularity, computer control and integrated design of sensors and instrumentation. What previously required several man-weeks of work is now achieved within a few hours time. With a presently unparalleled field performance, Laborelec has set the basis of new industrial standards

  19. The development of PC-based real time ultrasonic metal thickness inspection system

    International Nuclear Information System (INIS)

    This paper discusses the development of a PC-Based Real Time Ultrasonic Thickness Measurement system (UTMS) for metallic components such as pipes, pressure vessels and metal slabs. Metal thickness measurement for these components is crucial in industrial plants with dangerous environment, such as in oil and gas industry. From the measured metal thickness, a number of deductions could be made, for example the state and the rate of corrosion propagation inside a pipe or pressure vessel, etc. One of the most widely used methods in assessing metal thickness in industry is through the use of Ultrasonic technology. The benefits of using UTMS lies in the flexibility of data analysis, which includes signal processing, feature extraction, visualization capability and intelligent diagnosis. Data can be acquired in real-time and stored for future usage and application. The system was developed as a standalone computer software using Microsoft Visual-BASIC 6. (Author)

  20. Inspection of dissimilar metal welds in reactor pressure vessels in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Gadea, J.R.; Regidor, J.J.; Pelaez, J.A.; Serrano, P. [Tecnatom, S.A., San Sebastian de los Reyes, Madrid (Spain)

    2011-07-01

    MRP-139 recommendations for inspection of dissimilar metal (DM) welds in PWR vessels were launched in the last years in the USA. Basically, it increases the frequency of the examinations in these type of welds, with major emphasis in the hot loops, adding one intermediate inspection at the ten years interval in outlet nozzles. The spanish nuclear power plants (NPP's) have begun the implementation of this type of inspections on the vessel nozzles DM welds. As this type of inspections could have an impact in the critical path duration of the outage, it is necessary the use of a mechanical equipment able to examine the nozzles DM welds in a short vessel occupation time (VOT) with high quality, qualified techniques and minimum requirements of the refuelling platform. Tecnatom undertook the design and development of a new more advanced equipment, named TENIS-DM, for implementing the reactor pressure vessel (RPV) nozzles examination. This equipment was designed in order to accomplish the stringent requirements and the updated examination techniques; it was used for the inspection of the DM welds of Asco 1 NPP inlet and outlet nozzles in March 2011. Examination techniques and procedures were qualified through the GRUVAL validation program, based on ENIC methodology. Mechanical scanner was equipped with a large number of examination probes, and TV cameras -for visual inspection and also for monitoring the ultrasonic inspections. A remote operated submarine was also used to give support to the operational personnel during the manipulation of the equipment and its movements from one nozzle to the others. During two months before the inspection, tests of the complete inspection system were made on a nozzle mock-up installed in a 4 meters deep well at Tecnatom's facilities; this scenario was also used during the training sessions of the inspection crew. The defined technical and practical objectives were achieved: use of qualified techniques and minimal impact on the

  1. Inspection of dissimilar metal welds in reactor pressure vessels in Spain

    International Nuclear Information System (INIS)

    MRP-139 recommendations for inspection of dissimilar metal (DM) welds in PWR vessels were launched in the last years in the USA. Basically, it increases the frequency of the examinations in these type of welds, with major emphasis in the hot loops, adding one intermediate inspection at the ten years interval in outlet nozzles. The spanish nuclear power plants (NPP's) have begun the implementation of this type of inspections on the vessel nozzles DM welds. As this type of inspections could have an impact in the critical path duration of the outage, it is necessary the use of a mechanical equipment able to examine the nozzles DM welds in a short vessel occupation time (VOT) with high quality, qualified techniques and minimum requirements of the refuelling platform. Tecnatom undertook the design and development of a new more advanced equipment, named TENIS-DM, for implementing the reactor pressure vessel (RPV) nozzles examination. This equipment was designed in order to accomplish the stringent requirements and the updated examination techniques; it was used for the inspection of the DM welds of Asco 1 NPP inlet and outlet nozzles in March 2011. Examination techniques and procedures were qualified through the GRUVAL validation program, based on ENIC methodology. Mechanical scanner was equipped with a large number of examination probes, and TV cameras -for visual inspection and also for monitoring the ultrasonic inspections. A remote operated submarine was also used to give support to the operational personnel during the manipulation of the equipment and its movements from one nozzle to the others. During two months before the inspection, tests of the complete inspection system were made on a nozzle mock-up installed in a 4 meters deep well at Tecnatom's facilities; this scenario was also used during the training sessions of the inspection crew. The defined technical and practical objectives were achieved: use of qualified techniques and minimal impact on the critical

  2. Vibration based fault detection techniques for mechanical structures

    International Nuclear Information System (INIS)

    Fault detection techniques for mechanical structures and their application are becoming more important in recent years in the field of structure health monitoring. The intention of this paper is to present available state of the art methods that could be implemented in mechanical structures. Global based methods that contribute on detection, isolation and analysis of fault from changes in vibration characteristics of the structure are presented. Techniques are based on the idea that modal frequencies, mode shapes and modal damping as model properties of the structure can be determine as function of physical properties. In addition, if a fault appears in mechanical structure, this can be recognized as changes in the physical properties, which leads to cause changes in the modal properties of the structure. (Author)

  3. WAVELET-BASED WARPING TECHNIQUE FOR MOBILE DEVICES

    Directory of Open Access Journals (Sweden)

    Ekta Walia

    2014-07-01

    Full Text Available The role of digital images is increasing rapidly in mobile devices. They are used in many applications including virtual tours, virtual reality, e-commerce etc. Such applications synthesize realistic looking novel views of the reference images on mobile devices using the techniques like image-based rendering (IBR. However, with this increasing role of digital images comes the serious issue of processing large images which requires considerable time. Hence, methods to compress these large images are very important. Wavelets are excellent data compression tools that can be used with IBR algorithms to generate the novel views of compressed image data. This paper proposes a framework that uses wavelet-based warping technique to render novel views of compressed images on mobile/ handheld devices. The experiments are performed using Android Development Tools (ADT which shows the proposed framework gives better results for large images in terms of rendering time.

  4. Computer-vision-based gob inspection system for monitoring and control in the glass industry

    Science.gov (United States)

    Laizola, Eskarne; Jimenez, Antonio R.; Morgado, Fernando; Calvache, Mar; Seco, Fernando

    2003-05-01

    This paper presents a computer vision system for measuring the weight of gobs during a glass forming process, and a control strategy to correct automatically any weight deviation from a given set-point. During the formation of molten glass gobs, several noise sources can cause a deviation in the weight from a predefined reference value. Among them, there is a random white-noise disturbance caused by the lack of synchronisation of mechanical devices, the periodic disturbances due to changes in the spinning direction of the tube inside the feeder, and some long-term drifts caused by variations in temperature and viscosity of the raw glass material. The gob weight measurement system developed is based on a monochrome CCD high-resolution camera and photo-detector for synchronizing the frame acquisition. The molten glass provides the illumination, so a high contrast image is obtained with a bright object and dark background. Several image-processing algorithms are presented for reliable area estimation. Assuming that the gob is a symmetric geometry of revolution and uniform mass density, the proposed system estimates the weight of gobs with an accuracy better than +/-0.75%. A learning weight control strategy is proposed based on a PI-repetitive control scheme. The weight deviation from a set point is used as a control signal to adjust the glass flow into the feeder. This regulation scheme allows effective weight control, canceling mid and long-term effects. The tracking error, +/-1.5%, means a reduction of 40% when compared with a traditional PI controller.

  5. Visual inspection for CTBT verification

    Energy Technology Data Exchange (ETDEWEB)

    Hawkins, W.; Wohletz, K.

    1997-03-01

    On-site visual inspection will play an essential role in future Comprehensive Test Ban Treaty (CTBT) verification. Although seismic and remote sensing techniques are the best understood and most developed methods for detection of evasive testing of nuclear weapons, visual inspection can greatly augment the certainty and detail of understanding provided by these more traditional methods. Not only can visual inspection offer ``ground truth`` in cases of suspected nuclear testing, but it also can provide accurate source location and testing media properties necessary for detailed analysis of seismic records. For testing in violation of the CTBT, an offending party may attempt to conceal the test, which most likely will be achieved by underground burial. While such concealment may not prevent seismic detection, evidence of test deployment, location, and yield can be disguised. In this light, if a suspicious event is detected by seismic or other remote methods, visual inspection of the event area is necessary to document any evidence that might support a claim of nuclear testing and provide data needed to further interpret seismic records and guide further investigations. However, the methods for visual inspection are not widely known nor appreciated, and experience is presently limited. Visual inspection can be achieved by simple, non-intrusive means, primarily geological in nature, and it is the purpose of this report to describe the considerations, procedures, and equipment required to field such an inspection.

  6. Cognitive correlates of ultrasonic inspection performance

    International Nuclear Information System (INIS)

    This study provided a detailed examination of the thought processes required for conducting successful ultrasonic inspections of nuclear power plant components. When employed to detect or estimate the size of defects in components such as pipes and nozzles, an ultrasonic inspection can be a demanding cognitive task. A successful result requires the mental manipulation of a substantial amount of relevant information: knowledge about the component inspected, understanding of available ultrasonic techniques, and interpretation of an almost infinite variety of signal-characteristics obtained during the inspection. Reaching a correct conclusion from an inspection is a function of both the validity of the information obtained and the effectiveness with which the information is interpreted and weighed. Previous efforts to improve ultrasonic inspection performance have been directed mainly to the improvement of techniques and training for obtaining information. This study addressed improvement of the cognitive processes -- the mental manipulations required to reach a correct conclusion. The study was designed to learn what inspectors were doing and thinking while applying ultrasonic inspection techniques, and to relate key cognitive elements to inspection performance -- that is, to determine what aspects of these cognitive processes discriminate between effective and ineffective inspections. To this end, tape-recorded commentary was obtained and analyzed from 235 inspections of pipe-weld specimens. 26 refs., 39 figs

  7. A thermopneumatic micropump based on micro-engineering techniques

    OpenAIRE

    Pol, van der, P.; Lintel, van, H.T.G.; Elwenspoek, M; Fluitman, J.H.J.

    1990-01-01

    The design, working principle and realization of an electro-thermopneumatic liquid pump based on micro-engineering techniques are described. The pump, which is of the reciprocating displacement type, comprises a pump chamber, a thin silicon pump membrane and two silicon check valves to direct the flow. The dynamic pressure of an amount of gas contained in a cavity, controlled by resistive heating, actuates the pump membrane. The cavity, chambers, channels and valves are realized in silicon wa...

  8. Microanalysis of clay-based pigments by XRD techniques

    Czech Academy of Sciences Publication Activity Database

    Hradil, David; Bezdička, Petr; Hradilová, J.

    Catania : Technart, 2015. "O-48". [Technart 2015 : non-destructive and microanalytical techniques in art and cultural heritage. 27.04.2015-30.04.2015, Catania] R&D Projects: GA ČR GA14-22984S Keywords : micro-XRD * clay-based pigments * paintings Subject RIV: CA - Inorganic Chemistry http://technart2015.lns.infn.it/images/BoA.pdf

  9. WAVELET-BASED WARPING TECHNIQUE FOR MOBILE DEVICES

    OpenAIRE

    Ekta Walia; Vishal Verma,

    2014-01-01

    The role of digital images is increasing rapidly in mobile devices. They are used in many applications including virtual tours, virtual reality, e-commerce etc. Such applications synthesize realistic looking novel views of the reference images on mobile devices using the techniques like image-based rendering (IBR). However, with this increasing role of digital images comes the serious issue of processing large images which requires considerable time. Hence, methods to compress ...

  10. A microscopy technique based on bio-impedance sensors

    OpenAIRE

    Yúfera, A.; Huertas, Gloria; Olmo, Alberto

    2012-01-01

    It is proposed a microscopy for cell culture applications based on impedance sensors. The imagined signals are measured with the Electrical Cell-Substrate Spectroscopy (ECIS) technique, by identifying the cell area. The proposed microscopy allows real-time monitoring inside the incubator, reducing the contamination risk by human manipulation. It requires specific circuits for impedance measurements, a two-dimensional sensor array (pixels), and employing electrical models to decode efficiently...

  11. Ultrasonic Inspection Of Thick Sections

    Science.gov (United States)

    Friant, C. L.; Djordjevic, B. B.; O'Keefe, C. V.; Ferrell, W.; Klutz, T.

    1993-01-01

    Ultrasonics used to inspect large, relatively thick vessels for hidden defects. Report based on experiments in through-the-thickness transmission of ultrasonic waves in both steel and filament-wound composite cases of solid-fuel rocket motors.

  12. Ultrasonic inspection of turbine rotor discs for stress corrosion cracking

    International Nuclear Information System (INIS)

    Stress corrosion cracking in turbine discs and keyways has been recognised for a number of years as a problem. Magnox Electric has devised and implemented a strategy to manage the threat from SCC, based on a probabilistic risk assessment technique. An important input to the risk assessment is a knowledge of existing defects and Magnox Electric has undertaken a major programme of work to develop ultrasonic inspection techniques and equipment for SCC detection and sizing in the relevant disc geometries. (author)

  13. A Different Web-Based Geocoding Service Using Fuzzy Techniques

    Science.gov (United States)

    Pahlavani, P.; Abbaspour, R. A.; Zare Zadiny, A.

    2015-12-01

    Geocoding - the process of finding position based on descriptive data such as address or postal code - is considered as one of the most commonly used spatial analyses. Many online map providers such as Google Maps, Bing Maps and Yahoo Maps present geocoding as one of their basic capabilities. Despite the diversity of geocoding services, users usually face some limitations when they use available online geocoding services. In existing geocoding services, proximity and nearness concept is not modelled appropriately as well as these services search address only by address matching based on descriptive data. In addition there are also some limitations in display searching results. Resolving these limitations can enhance efficiency of the existing geocoding services. This paper proposes the idea of integrating fuzzy technique with geocoding process to resolve these limitations. In order to implement the proposed method, a web-based system is designed. In proposed method, nearness to places is defined by fuzzy membership functions and multiple fuzzy distance maps are created. Then these fuzzy distance maps are integrated using fuzzy overlay technique for obtain the results. Proposed methods provides different capabilities for users such as ability to search multi-part addresses, searching places based on their location, non-point representation of results as well as displaying search results based on their priority.

  14. Waste inspection tomography (WIT)

    International Nuclear Information System (INIS)

    The WIT program will provide an inspection system that offers the nuclear waste evaluator a unique combination of tools for regulatory-driven characterization of low-level waste (LLW), transuranic waste (TRU), and mixed waste drums. WIT provides nondestructive, noninvasive, and environmentally safe inspections using X-ray and gamma ray technologies, with reasonable cost and throughput. Two emission imaging techniques will be employed for characterizing materials in waste containers. The first of these is gamma emission tomography, commonly called single-photon emission computed tomography (SPECT). Rather than using an external radiation source, SPECT uses the emission of radioactive materials within the object of interest for imaging. In this case, emission from actual nuclear waste within a container will provide a three-dimensional image of the radioactive substances in the container. The second emission technique will use high-purity germanium detectors for gamma ray spectroscopy. This technique, called nondestructive assay (NDA), can identify the emitting isotopic species and strength. Work in emission tomography and assay of nuclear waste has been undertaken at Lawrence Livermore National Laboratory using a technique called Passive Tomography. Results from a process development unit are presented

  15. Safety Justification of Software Systems. Software Based Safety Systems. Regulatory Inspection Handbook

    International Nuclear Information System (INIS)

    The introduction of new software based technology in the safety systems in nuclear power plants also makes it necessary to develop new strategies for regulatory review and assessment of these new systems that is more focused on reviewing the processes at the different phases in design phases during the system life cycle. It is a general requirement that the licensee shall perform different kinds of reviews. From a regulatory point of view it is more cost effective to assess that the design activities at the suppliers and the review activities within the development project are performed with good quality. But the change from more technical reviews over to the development process oriented approach also cause problems. When reviewing development and quality aspects there are no 'hard facts' that can be judged against some specified criteria, the issues are more 'soft' and are more to build up structure of arguments and evidences that the requirements are met. The regulatory review strategy must therefore change to follow the development process over the whole life cycle from concept phase until installation and operation. Even if we know what factors that is of interest we need some guidance on how to interpret and judge the information.For that purpose SKl started research activities in this area at the end of the 1990s. In the first phase, in co-operation with Gustav Dahll at the Halden project, a life cycle model was selected. For the different phases a qualitative influence net was constructed of the type that is used in Bayesian Believe Network together with a discussion on different issues involved. In the second phase of the research work, in co-operation with Norman Wainwright, a former NII inspector, information from a selection of the most important sources as guidelines, IAEA and EC reports etc, was mapped into the influence net structure (the total list on used sources are in the report). The result is presented in the form of questions (Q) and a

  16. Safety Justification of Software Systems. Software Based Safety Systems. Regulatory Inspection Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Dahll, Gustav (OECD Halden Project, Halden (NO)); Liwaang, Bo (Swedish Nuclear Power Inspectorate, Stockholm (Sweden)); Wainwright, Norman (Wainwright Safety Advice (GB))

    2006-07-01

    The introduction of new software based technology in the safety systems in nuclear power plants also makes it necessary to develop new strategies for regulatory review and assessment of these new systems that is more focused on reviewing the processes at the different phases in design phases during the system life cycle. It is a general requirement that the licensee shall perform different kinds of reviews. From a regulatory point of view it is more cost effective to assess that the design activities at the suppliers and the review activities within the development project are performed with good quality. But the change from more technical reviews over to the development process oriented approach also cause problems. When reviewing development and quality aspects there are no 'hard facts' that can be judged against some specified criteria, the issues are more 'soft' and are more to build up structure of arguments and evidences that the requirements are met. The regulatory review strategy must therefore change to follow the development process over the whole life cycle from concept phase until installation and operation. Even if we know what factors that is of interest we need some guidance on how to interpret and judge the information.For that purpose SKl started research activities in this area at the end of the 1990s. In the first phase, in co-operation with Gustav Dahll at the Halden project, a life cycle model was selected. For the different phases a qualitative influence net was constructed of the type that is used in Bayesian Believe Network together with a discussion on different issues involved. In the second phase of the research work, in co-operation with Norman Wainwright, a former NII inspector, information from a selection of the most important sources as guidelines, IAEA and EC reports etc, was mapped into the influence net structure (the total list on used sources are in the report). The result is presented in the form of

  17. Ultrasonic inspection of austenitic welds

    International Nuclear Information System (INIS)

    The metallurgical structure of austenitic welds is described and contrasted with that found in ferritic welds. It is shown that this structure imparts a marked elastic anisotropy in the ultrasonic propagation parameters. Measurements of variations in the apparent attenuation of sound and deviations in the beam direction are described. The measurements are interpreted in terms of the measured velocity anisotropy. Two applications of the fundamental work are described. In the first it is shown how, by using short pulse compression wave probes, and with major modification of the welding procedure, a stainless steel fillet weld in an AGR boiler can be inspected. In the second application, alternative designs of a transition butt weld have been compared for ease of ultrasonic inspection. The effects of two different welding processes on such an inspection are described. Finally, the paper examines the prospects for future development of inspection and defect-sizing techniques for austenitic welds. (author)

  18. Hydrocarbon microseepage mapping using signature based target detection techniques

    Science.gov (United States)

    Soydan, Hilal; Koz, Alper; Şebnem Düzgün, H.; Aydin Alatan, A.

    2015-10-01

    In this paper, we compare the conventional methods in hydrocarbon seepage anomalies with the signature based detection algorithms. The Crosta technique [1] is selected as a basement in the experimental comparisons for the conventional approach. The Crosta technique utilizes the characteristic bands of the searched target for principal component transformation in order to determine the components characterizing the target in interest. Desired Target Detection and Classification Algorithm (DTDCA), Spectral Matched Filter (SMF), and Normalized Correlation (NC) are employed for signature based target detection. Signature based target detection algorithms are applied to the whole spectrum benefiting from the information stored in all spectral bands. The selected methods are applied to a multispectral Advanced SpaceBorne Thermal Emission and Radiometer (ASTER) image of the study region, with an atmospheric correction prior to the realization of the algorithms. ASTER provides multispectral bands covering visible, short wave, and thermal infrared region, which serves as a useful tool for the interpretation of the areas with hydrocarbon anomalies. The exploration area is selected as Gemrik Anticline which is located in South East Anatolia, Adıyaman, Bozova Oil Field, where microseeps can be observed with almost no vegetation cover. The spectral signatures collected with Analytical Spectral Devices Inc. (ASD) spectrometer from the reference valley [2] have been utilized as an input to the signature based detection algorithms. The experiments have indicated that DTDCA and MF outperforms the Crosta technique by locating the microseepage patterns along the mitigation pathways with a better contrast. On the other hand, NC has not been able to map the searched target with a visible distinction. It is concluded that the signature based algorithms can be more effective than the conventional methods for the detection of microseepage induced anomalies.

  19. Performance Based Novel Techniques for Semantic Web Mining

    Directory of Open Access Journals (Sweden)

    Mahendra Thakur

    2012-01-01

    Full Text Available The explosive growth in the size and use of the World Wide Web continuously creates new great challenges and needs. The need for predicting the users preferences in order to expedite and improve the browsing though a site can be achieved through personalizing of the websites. Most of the research efforts in web personalization correspond to the evolution of extensive research in web usage mining, i.e. the exploitation of the navigational patterns of the web site visitors. When a personalization system relies solely on usage-based results, however, valuable information conceptually related to what is finally recommended may be missed. Moreover, the structural properties of the web site are often disregarded. In this paper, we propose novel techniques that use the content semantics and the structural properties of a web site in order to improve the effectiveness of web personalization. In the first part of our work we present standing for Semantic Web Personalization, a personalization system that integrates usage data with content semantics, expressed in ontology terms, in order to compute semantically enhanced navigational patterns and effectively generate useful recommendations. To the best of our knowledge, our proposed technique is the only semantic web personalization system that may be used by non-semantic web sites. In the second part of our work, we present a novel approach for enhancing the quality of recommendations based on the underlying structure of a web site. We introduce UPR (Usage-based PageRank, a PageRank-style algorithm that relies on the recorded usage data and link analysis techniques. Overall, we demonstrate that our proposed hybrid personalization framework results in more objective and representative predictions than existing techniques.

  20. Inspection systems for valves monitoring at EDF

    International Nuclear Information System (INIS)

    Electricite de France (EDF) makes increasing use of valve inspection systems to guarantee safety in its pressurized water reactor plants, improve plant availability and facilitate condition-based maintenance. A portable system known as SAMIR has been developed for inspection of motor-operated valves, and is now used on EDF's 900-MW sites. For its 1300-MW units, EDF has chosen a more complete system which enables measuring thrust on the valve stem during a maneuver, using a sensor mounted on the yoke. To detect internal vale leaks, an on-site assessment has demonstrated the economic benefits of acoustic emission techniques. EDF has equipped its sites with analog leak detection systems which may soon be replaced by a digital model now being developed. (authors)

  1. Regression based peak load forecasting using a transformation technique

    International Nuclear Information System (INIS)

    This paper presents a regression based daily peak load forecasting method with a transformation technique. In order to forecast the load precisely through a year, the authors should consider seasonal load change, annual load growth and the latest daily load change. To deal with these characteristics in the load forecasting, a transformation technique is presented. This technique consists of a transformation function with translation and reflection methods. The transformation function is estimated with the previous year's data points, in order that the function converts the data points into a set of new data points with preserving the shape of temperature-load relationships in the previous year. Then, the function is slightly translated so that the transformed data points will fit the shape of temperature-load relationships in the year. Finally, multivariate regression analysis with the latest daily loads and weather observations estimates the forecasting model. Large forecasting errors caused by the weather-load nonlinear characteristic in the transitional seasons such as spring and fall are reduced. Performance of the technique which is verified with simulations on actual load data of Tokyo Electric Power Company is also described

  2. Development of a two-stage inspection process for the assessment of deteriorating infrastructure

    International Nuclear Information System (INIS)

    Inspection-based maintenance strategies can provide an efficient tool for the management of ageing infrastructure subjected to deterioration. Many of these methods rely on quantitative data from inspections, rather than qualitative and subjective data. The focus of this paper is on the development of an inspection-based decision scheme, incorporating analysis on the effect of the cost and quality of NDT tools to assess the condition of infrastructure elements/networks during their lifetime. For the first time the two aspects of an inspection are considered, i.e. detection and sizing. Since each stage of an inspection is carried out for a distinct purpose, different parameters are used to represent each procedure and both have been incorporated into a maintenance management model. The separation of these procedures allows the interaction between the two inspection techniques to be studied. The inspection for detection process acts as a screening exercise to determine which defects require further inspection for sizing. A decision tool is developed that allows the owner/manager of the infrastructural element/network to choose the most cost-efficient maintenance management plan based on his/her specific requirements.

  3. Noninvasive in vivo glucose sensing using an iris based technique

    Science.gov (United States)

    Webb, Anthony J.; Cameron, Brent D.

    2011-03-01

    Physiological glucose monitoring is important aspect in the treatment of individuals afflicted with diabetes mellitus. Although invasive techniques for glucose monitoring are widely available, it would be very beneficial to make such measurements in a noninvasive manner. In this study, a New Zealand White (NZW) rabbit animal model was utilized to evaluate a developed iris-based imaging technique for the in vivo measurement of physiological glucose concentration. The animals were anesthetized with isoflurane and an insulin/dextrose protocol was used to control blood glucose concentration. To further help restrict eye movement, a developed ocular fixation device was used. During the experimental time frame, near infrared illuminated iris images were acquired along with corresponding discrete blood glucose measurements taken with a handheld glucometer. Calibration was performed using an image based Partial Least Squares (PLS) technique. Independent validation was also performed to assess model performance along with Clarke Error Grid Analysis (CEGA). Initial validation results were promising and show that a high percentage of the predicted glucose concentrations are within 20% of the reference values.

  4. IMAGE SEGMENTATION BASED ON MARKOV RANDOM FIELD AND WATERSHED TECHNIQUES

    Institute of Scientific and Technical Information of China (English)

    纳瑟; 刘重庆

    2002-01-01

    This paper presented a method that incorporates Markov Random Field(MRF), watershed segmentation and merging techniques for performing image segmentation and edge detection tasks. MRF is used to obtain an initial estimate of x regions in the image under process where in MRF model, gray level x, at pixel location i, in an image X, depends on the gray levels of neighboring pixels. The process needs an initial segmented result. An initial segmentation is got based on K-means clustering technique and the minimum distance, then the region process in modeled by MRF to obtain an image contains different intensity regions. Starting from this we calculate the gradient values of that image and then employ a watershed technique. When using MRF method it obtains an image that has different intensity regions and has all the edge and region information, then it improves the segmentation result by superimpose closed and an accurate boundary of each region using watershed algorithm. After all pixels of the segmented regions have been processed, a map of primitive region with edges is generated. Finally, a merge process based on averaged mean values is employed. The final segmentation and edge detection result is one closed boundary per actual region in the image.

  5. New modulation-based watermarking technique for video

    Science.gov (United States)

    Lemma, Aweke; van der Veen, Michiel; Celik, Mehmet

    2006-02-01

    Successful watermarking algorithms have already been developed for various applications ranging from meta-data tagging to forensic tracking. Nevertheless, it is commendable to develop alternative watermarking techniques that provide a broader basis for meeting emerging services, usage models and security threats. To this end, we propose a new multiplicative watermarking technique for video, which is based on the principles of our successful MASK audio watermark. Audio-MASK has embedded the watermark by modulating the short-time envelope of the audio signal and performed detection using a simple envelope detector followed by a SPOMF (symmetrical phase-only matched filter). Video-MASK takes a similar approach and modulates the image luminance envelope. In addition, it incorporates a simple model to account for the luminance sensitivity of the HVS (human visual system). Preliminary tests show algorithms transparency and robustness to lossy compression.

  6. An Improved Face Recognition Technique Based on Modular LPCA Approach

    Directory of Open Access Journals (Sweden)

    Mathu S.S. Kumar

    2011-01-01

    Full Text Available Problem statement: A face identification algorithm based on modular localized variation by Eigen Subspace technique, also called modular localized principal component analysis, is presented in this study. Approach: The face imagery was partitioned into smaller sub-divisions from a predefined neighborhood and they were ultimately fused to acquire many sets of features. Since a few of the normal facial features of an individual do not differ even when the pose and illumination may differ, the proposed method manages these variations. Results: The proposed feature selection module has significantly, enhanced the identification precision using standard face databases when compared to conservative and modular PCA techniques. Conclusion: The proposed algorithm, when related with conservative PCA algorithm and modular PCA, has enhanced recognition accuracy for face imagery with illumination, expression and pose variations.

  7. Studying Satellite Image Quality Based on the Fusion Techniques

    CERN Document Server

    Al-Wassai, Firouz Abdullah; Al-Zaky, Ali A

    2011-01-01

    Various and different methods can be used to produce high-resolution multispectral images from high-resolution panchromatic image (PAN) and low-resolution multispectral images (MS), mostly on the pixel level. However, the jury is still out on the benefits of a fused image compared to its original images. There is also a lack of measures for assessing the objective quality of the spatial resolution for the fusion methods. Therefore, an objective quality of the spatial resolution assessment for fusion images is required. So, this study attempts to develop a new qualitative assessment to evaluate the spatial quality of the pan sharpened images by many spatial quality metrics. Also, this paper deals with a comparison of various image fusion techniques based on pixel and feature fusion techniques.

  8. 3D laser inspection of fuel assembly grid spacers for nuclear reactors based on diffractive optical elements

    Science.gov (United States)

    Finogenov, L. V.; Lemeshko, Yu A.; Zav'yalov, P. S.; Chugui, Yu V.

    2007-06-01

    Ensuring the safety and high operation reliability of nuclear reactors takes 100% inspection of geometrical parameters of fuel assemblies, which include the grid spacers performed as a cellular structure with fuel elements. The required grid spacer geometry of assembly in the transverse and longitudinal cross sections is extremely important for maintaining the necessary heat regime. A universal method for 3D grid spacer inspection using a diffractive optical element (DOE), which generates as the structural illumination a multiple-ring pattern on the inner surface of a grid spacer cell, is investigated. Using some DOEs one can inspect the nomenclature of all produced grids. A special objective has been developed for forming the inner surface cell image. The problems of diffractive elements synthesis, projecting optics calculation, adjusting methods as well as calibration of the experimental measuring system are considered. The algorithms for image processing for different constructive elements of grids (cell, channel hole, outer grid spacer rim) and the experimental results are presented.

  9. Flight route Designing and mission planning Of power line inspecting system Based On multi-sensor UAV

    International Nuclear Information System (INIS)

    In order to obtain various information of power facilities such as spatial location, geometry, images data and video information in the infrared and ultraviolet band and so on, Unmanned Aerial Vehicle (UAV) power line inspecting system needs to integrate a variety of sensors for data collection. Low altitude and side-looking imaging are required for UAV flight to ensure sensors to acquire high-quality data and device security. In this paper, UAV power line inspecting system is deferent from existing ones that used in Surveying and Mapping. According to characteristics of UAV for example equipped multiple sensor, side-looking imaging, working at low altitude, complex terrain conditions and corridor type flight, this paper puts forward a UAV power line inspecting scheme which comprehensively considered of the UAV performance, sensor parameters and task requirements. The scheme is finally tested in a region of Guangdong province, and the preliminary results show that the scheme is feasible

  10. Development of a Pin Hall Remote Inspection System based on Auto-Recognition of the Hall Center

    International Nuclear Information System (INIS)

    Many of the safety instruments are related to the NPP coolant systems. The first coolant system includes radioactive contaminated water and the secondary coolant system includes clean water. If there are some defects in the coolant systems, these conditions may cause serious accidents such as the loss of national electric power and of human lives. So the diagnosis of the coolant systems has become an important issue in the nuclear power plant. The environments of diagnoses in the nuclear power plant are very dangerous to the human. So the auto inspection and monitoring methods have been adapted to NPP's diagnoses. We have developed a pin inspection system that includes an inspection robot, an image processing system, a web-server and various control systems

  11. Feature-based multiresolution techniques for product design

    Institute of Scientific and Technical Information of China (English)

    LEE Sang Hun; LEE Kunwoo

    2006-01-01

    3D computer-aided design (CAD) systems based on feature-based solid modelling technique have been widely spread and used for product design. However, when part models associated with features are used in various downstream applications,simplified models in various levels of detail (LODs) are frequently more desirable than the full details of the parts. In particular,the need for feature-based multiresolution representation of a solid model representing an object at multiple LODs in the feature unit is increasing for engineering tasks. One challenge is to generate valid models at various LODs after an arbitrary rearrangement of features using a certain LOD criterion, because composite Boolean operations consisting of union and subtraction are not commutative. The other challenges are to devise proper topological framework for multiresolution representation, to suggest more reasonable LOD criteria, and to extend applications. This paper surveys the recent research on these issues.

  12. Visual inspection. Better than your eyes

    International Nuclear Information System (INIS)

    Ongoing improvements in the development of camera technologies and manipulator techniques permit an enhanced performance of inspection tasks in nuclear services. In areas of reduced dose rate it's possible to use small size high resolution CCD cameras instead of tube cameras. Underwater inspections may be performed by submarine instead of rigid manipulator systems. This allows the enlargement of inspection areas and the performance at reduced time and personnel dose rate. (author)

  13. Rules for Supervision and Inspection of Offshore Oil Industry

    Institute of Scientific and Technical Information of China (English)

    Dai Zhongliang; Song Lisong

    1994-01-01

    @@ In short,safety supervision and technique inspection mean the safety supervision by the government,and the inspection by technical organization,and those are put into practice by a series of administrative rules and regulations.

  14. Transformer-based design techniques for oscillators and frequency dividers

    CERN Document Server

    Luong, Howard Cam

    2016-01-01

    This book provides in-depth coverage of transformer-based design techniques that enable CMOS oscillators and frequency dividers to achieve state-of-the-art performance.  Design, optimization, and measured performance of oscillators and frequency dividers for different applications are discussed in detail, focusing on not only ultra-low supply voltage but also ultra-wide frequency tuning range and locking range.  This book will be an invaluable reference for anyone working or interested in CMOS radio-frequency or mm-Wave integrated circuits and systems.

  15. Line impedance estimation using model based identification technique

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai; Agelidis, Vassilios; Teodorescu, Remus

    into the operation of the grid-connected power converters. This paper describes a quasi passive method for estimating the line impedance of the distribution electricity network. The method uses the model based identification technique to obtain the resistive and inductive parts of the line impedance....... The quasi-passive behaviour of the proposed method comes from the combination of the non intrusive behaviour of the passive methods with a better accuracy of the active methods. The simulation results reveal the good accuracy of the proposed method....

  16. Coupled cavity model based on the mode matching technique

    CERN Document Server

    Ayzatsky, M I

    2015-01-01

    We have developed the mode matching technique that is based on the using the eigenmodes of circular cavities and the eigenwaves of circular waveguides as the basic functions for calculation the properties of nonuniform disc-loaded waveguides. We have obtained exact infinite systems of coupled equations which can be reduced by making some assumptions. Under such procedure we can receive more exact parameters of nonuniform equivalent circuits by solving the appropriative algebraic systems. These parameters of equivalent circuits are functions both geometric sizes and frequency. Moreover, under such approach all used values have interpretation. We called this approach as coupled cavity model.

  17. Simultaneous algebraic reconstruction technique based on guided image filtering.

    Science.gov (United States)

    Ji, Dongjiang; Qu, Gangrong; Liu, Baodong

    2016-07-11

    The challenge of computed tomography is to reconstruct high-quality images from few-view projections. Using a prior guidance image, guided image filtering smoothes images while preserving edge features. The prior guidance image can be incorporated into the image reconstruction process to improve image quality. We propose a new simultaneous algebraic reconstruction technique based on guided image filtering. Specifically, the prior guidance image is updated in the image reconstruction process, merging information iteratively. To validate the algorithm practicality and efficiency, experiments were performed with numerical phantom projection data and real projection data. The results demonstrate that the proposed method is effective and efficient for nondestructive testing and rock mechanics. PMID:27410859

  18. A newly developed technique of wireless remote controlled visual inspection system for neutron guides of cold neutron research facilities at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Hyung; Cho, Yeong Garp; Kim, Jong In [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    KAERI developed a neutron guide system for cold neutron research facilities at HANARO from 2003 to 2010. In 2008, the old plug shutter and instruments were removed, and a new plug and primary shutter were installed as the first cold neutron delivery system at HANARO. At the beginning of 2010, all the neutron guides and accessories had been successfully installed as well. The neutron guide system of HANARO consists of the in pile plug assembly with in pile guides, the primary shutter with in shutter guides, the neutron guides in the guide shielding room with secondary shutter, and the neutron guides in the neutron guide hall. Three kinds of glass materials were selected with optimum lengths by considering their lifetime, shielding, maintainability and cost as well. Radiation damage of the guides can occur on the coating and glass by neutron capturing in the glass. It is a big challenge to inspect a guide failure because of the difficult surrounding environment, such as high level radiation, limited working space, and massive hard work for removing and reinstalling the shielding blocks as shown in Fig 1. Therefore, KAERI has developed a wireless remote controlled visual inspection system for neutron guides using an infrared light camera mounted on the vehicle moving in the guide.

  19. A newly developed technique of wireless remote controlled visual inspection system for neutron guides of cold neutron research facilities at HANARO

    International Nuclear Information System (INIS)

    KAERI developed a neutron guide system for cold neutron research facilities at HANARO from 2003 to 2010. In 2008, the old plug shutter and instruments were removed, and a new plug and primary shutter were installed as the first cold neutron delivery system at HANARO. At the beginning of 2010, all the neutron guides and accessories had been successfully installed as well. The neutron guide system of HANARO consists of the in pile plug assembly with in pile guides, the primary shutter with in shutter guides, the neutron guides in the guide shielding room with secondary shutter, and the neutron guides in the neutron guide hall. Three kinds of glass materials were selected with optimum lengths by considering their lifetime, shielding, maintainability and cost as well. Radiation damage of the guides can occur on the coating and glass by neutron capturing in the glass. It is a big challenge to inspect a guide failure because of the difficult surrounding environment, such as high level radiation, limited working space, and massive hard work for removing and reinstalling the shielding blocks as shown in Fig 1. Therefore, KAERI has developed a wireless remote controlled visual inspection system for neutron guides using an infrared light camera mounted on the vehicle moving in the guide

  20. Design of a facility for the automated receipt inspection and characterization of LILW using integrated non-destructive examination and assay techniques

    International Nuclear Information System (INIS)

    KHNP is constructing two repositories, located in Bonggil-ri, Yangbukmyun, Gyeongju-si, Gyeongbuk, Korea, for Low and Intermediate Level radioactive waste (LILW). The waste received is required to be inspected and characterized prior to being placed into storage at the repository. This paper describes the design of an integrated system of non destructive examination (X-ray), and non destructive assay (radiometric) instrument systems, waste package integrity checking systems, waste handling mechanisms and data management and archival provisions, which comprise the Waste Receipt and Inspection Facility (WRIF). The WRIF is designed to uncap transport containers, unload waste drums from containers, safely examine the drums, to ensure they meet the waste acceptance criteria established by the LILW facility. The drums are then loaded into waste disposal containers for transfer to the repository. The WRIF also receives larger waste containers, which are characterized in a separate section of the WRIF, before being transferred to the repository. Remote control and handling of the waste is a design requirement, as well as the management, processing archival and retrieval system for all data generated during waste characterization. (authors)

  1. Methodology to identify risk-significant components for inservice inspection and testing

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.T.; Hartley, R.S.; Jones, J.L. Jr.; Kido, C.; Phillips, J.H.

    1992-08-01

    Periodic inspection and testing of vital system components should be performed to ensure the safe and reliable operation of Department of Energy (DOE) nuclear processing facilities. Probabilistic techniques may be used to help identify and rank components by their relative risk. A risk-based ranking would allow varied DOE sites to implement inspection and testing programs in an effective and cost-efficient manner. This report describes a methodology that can be used to rank components, while addressing multiple risk issues.

  2. Methodology to identify risk-significant components for inservice inspection and testing

    International Nuclear Information System (INIS)

    Periodic inspection and testing of vital system components should be performed to ensure the safe and reliable operation of Department of Energy (DOE) nuclear processing facilities. Probabilistic techniques may be used to help identify and rank components by their relative risk. A risk-based ranking would allow varied DOE sites to implement inspection and testing programs in an effective and cost-efficient manner. This report describes a methodology that can be used to rank components, while addressing multiple risk issues

  3. A Comparative Analysis of Exemplar Based and Wavelet Based Inpainting Technique

    Directory of Open Access Journals (Sweden)

    Vaibhav V Nalawade

    2012-06-01

    Full Text Available Image inpainting is the process of filling in of missing region so as to preserve its overall continuity. Image inpainting is manipulation and modification of an image in a form that is not easily detected. Digital image inpainting is relatively new area of research, but numerous and different approaches to tackle the inpainting problem have been proposed since the concept was first introduced. This paper compares two separate techniques viz, Exemplar based inpainting technique and Wavelet based inpainting technique, each portraying a different set of characteristics. The algorithms analyzed under exemplar technique are large object removal by exemplar based inpainting technique (Criminisi’s and modified exemplar (Cheng. The algorithm analyzed under wavelet is Chen’s visual image inpainting method. A number of examples on real and synthetic images are demonstrated to compare the results of different algorithms using both qualitative and quantitative parameters.

  4. Nuclear fuel pellet quality control using artificial intelligence techniques

    Science.gov (United States)

    Song, Xiaolong

    Inspection of nuclear fuel pellets is a complex and time-consuming process. At present, quality control in the fuel fabrication field mainly relies on human manual inspection, which is essentially a judgement call. Considering the high quality requirement of fuel pellets in the nuclear industry, pellet inspection systems must have a high accuracy rate in addition to a high inspection speed. Furthermore, any inspection process should have a low rejection rate of good pellets from the manufacturer point of view. It is very difficult to use traditional techniques, such as simple image comparison, to adequately perform the inspection process of the nuclear fuel pellet. Knowledge-based inspection and a defect-recognition algorithm, which maps the human inspection knowledge, is more robust and effective. A novel method is introduced here for pellet image processing. Three artificial intelligence techniques are studied and applied for fuel pellet inspection in this research. They are an artificial neural network, fuzzy logic, and the decision tree method. A dynamic reference model is located on each input fuel pellet image. Then, those pixels that belong to the abnormal defect are enhanced with high speed and high accuracy. Next, the content-based features for the defect are extracted from those abno1mal pixels and used in the inspection algorithm. Finally, an automated inspection prototype system---Visual Inspection Studio---which combines machine vision and these three AI techniques, is developed and tested. The experimental results indicate a very successful system with a high potential for on-line automatic inspection process.

  5. Structural level characterization of base oils using advanced analytical techniques

    KAUST Repository

    Hourani, Nadim

    2015-05-21

    Base oils, blended for finished lubricant formulations, are classified by the American Petroleum Institute into five groups, viz., groups I-V. Groups I-III consist of petroleum based hydrocarbons whereas groups IV and V are made of synthetic polymers. In the present study, five base oil samples belonging to groups I and III were extensively characterized using high performance liquid chromatography (HPLC), comprehensive two-dimensional gas chromatography (GC×GC), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) equipped with atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) sources. First, the capabilities and limitations of each analytical technique were evaluated, and then the availed information was combined to reveal compositional details on the base oil samples studied. HPLC showed the overwhelming presence of saturated over aromatic compounds in all five base oils. A similar trend was further corroborated using GC×GC, which yielded semiquantitative information on the compound classes present in the samples and provided further details on the carbon number distributions within these classes. In addition to chromatography methods, FT-ICR MS supplemented the compositional information on the base oil samples by resolving the aromatics compounds into alkyl- and naphtheno-subtituted families. APCI proved more effective for the ionization of the highly saturated base oil components compared to APPI. Furthermore, for the detailed information on hydrocarbon molecules FT-ICR MS revealed the presence of saturated and aromatic sulfur species in all base oil samples. The results presented herein offer a unique perspective into the detailed molecular structure of base oils typically used to formulate lubricants. © 2015 American Chemical Society.

  6. Radiation synthesized protein-based nanoparticles: A technique overview

    International Nuclear Information System (INIS)

    Seeking for alternative routes for protein engineering a novel technique – radiation induced synthesis of protein nanoparticles – to achieve size controlled particles with preserved bioactivity has been recently reported. This work aimed to evaluate different process conditions to optimize and provide an overview of the technique using γ-irradiation. Papain was used as model protease and the samples were irradiated in a gamma cell irradiator in phosphate buffer (pH=7.0) containing ethanol (0–35%). The dose effect was evaluated by exposure to distinct γ-irradiation doses (2.5, 5, 7.5 and 10 kGy) and scale up experiments involving distinct protein concentrations (12.5–50 mg mL−1) were also performed. Characterization involved size monitoring using dynamic light scattering. Bityrosine detection was performed using fluorescence measurements in order to provide experimental evidence of the mechanism involved. Best dose effects were achieved at 10 kGy with regard to size and no relevant changes were observed as a function of papain concentration, highlighting very broad operational concentration range. Bityrosine changes were identified for the samples as a function of the process confirming that such linkages play an important role in the nanoparticle formation. - Highlights: • Synthesis of protein-based nanoparticles by γ-irradiation. • Optimization of the technique. • Overview of mechanism involved in the nanoparticle formation. • Engineered papain nanoparticles for biomedical applications

  7. Optimizing in-service inspection

    International Nuclear Information System (INIS)

    In the present paper, the aspects of optimizing In-Service Inspection (ISI) is discussed. Slovenian Nuclear Safety Administration (SNSA) and its authorized organization for the ISI activities, Institute of Metals and Technologies, are permanently involved in the ISI process of the nuclear power plant (NPP) Krsko. Based on this experience and additionally gathered by reviewing of the new ISI program, the decision was made to improve recent regulatory and professional practice. Traditional criteria, standards and practice are bases for the further improvements. Improvements will be done by adding a new knowledge about the safety important components of the systems to the basic practice. It is necessary to identify conditions of the safety important components, such as realistic stress and fatigue conditions, material properties changes due aging processes, the temperature cycling effects, existing flaws characterization in the light of the previous detection and equipment technique used, assessment of the measurement accuracy on the results etc. In addition to the above mentioned, risk assessment and evaluation of the whole ISI shall be done. To do this it is necessary to make risk evaluation, based on previous structural element probability assessment. Probabilistic risk assessment is important and one of the most powerful tools in the ISI optimization. Some basic work in the field of the risk informed methods related to the nuclear safety components has been already done. Based on reference documentation, the most important steps in risk informed ISI are discussed. Those steps are scope definition, consequence evaluation, failure probability estimation, risk evaluation, nondestructive examination method selection and possibilities of implementation, monitoring and feedback. Recent experience on the ISI in the nuclear world show that such practice is very important during ISI decision making process and has some measurable effects too. It is clear that classical

  8. DIDACTIC BASES OF EXPLICIT AND IMPLICIT TRAINING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Nail Iskanderov

    2015-08-01

    Full Text Available The article highlights the study of the evolutionary movement of scientific and pedagogical thought in recent decades, a trend of movement from the issues of improving the organization of the learning process through the increased efficiency of the educational process to the problem of understanding the nature of mental processes, analyzes the state of psychological and pedagogical methods of teaching, summarizes instructional methods, associated with the implicit and explicit formation of knowledge, develops the scheme, based on the internal logic of the relationship of neural ensembles, allowing to form stage-by-stage and develop a frame-based and conceptual organization of knowledge in the process of learning new information, considers the features and classification of explicit and implicit methods and techniques of training, and the possibility of using these methods in teaching, shows the similarities and differences between the terms "concept", "frame" and "cognitom", explains the insight into implicit and explicit teaching methodology.

  9. On HTML and XML based web design and implementation techniques

    International Nuclear Information System (INIS)

    Web implementation is truly a multidisciplinary field with influences from programming, choosing of scripting languages, graphic design, user interface design, and database design. The challenge of a Web designer/implementer is his ability to create an attractive and informative Web. To work with the universal framework and link diagrams from the design process as well as the Web specifications and domain information, it is essential to create Hypertext Markup Language (HTML) or other software and multimedia to accomplish the Web's objective. In this article we will discuss Web design standards and the techniques involved in Web implementation based on HTML and Extensible Markup Language (XML). We will also discuss the advantages and disadvantages of HTML over its successor XML in designing and implementing a Web. We have developed two Web pages, one utilizing the features of HTML and the other based on the features of XML to carry out the present investigation. (author)

  10. Designing on ICT reconstruction software based on DSP techniques

    International Nuclear Information System (INIS)

    The convolution back project (CBP) algorithm is used to realize the CT image's reconstruction in ICT generally, which is finished by using PC or workstation. In order to add the ability of multi-platform operation of CT reconstruction software, a CT reconstruction method based on modern digital signal processor (DSP) technique is proposed and realized in this paper. The hardware system based on TI's C6701 DSP processor is selected to support the CT software construction. The CT reconstruction software is compiled only using assembly language related to the DSP hardware. The CT software can be run on TI's C6701 EVM board by inputting the CT data, and can get the CT Images that satisfy the real demands. (authors)

  11. Evolutionary Based Techniques for Fault Tolerant Field Programmable Gate Arrays

    Science.gov (United States)

    Larchev, Gregory V.; Lohn, Jason D.

    2006-01-01

    The use of SRAM-based Field Programmable Gate Arrays (FPGAs) is becoming more and more prevalent in space applications. Commercial-grade FPGAs are potentially susceptible to permanently debilitating Single-Event Latchups (SELs). Repair methods based on Evolutionary Algorithms may be applied to FPGA circuits to enable successful fault recovery. This paper presents the experimental results of applying such methods to repair four commonly used circuits (quadrature decoder, 3-by-3-bit multiplier, 3-by-3-bit adder, 440-7 decoder) into which a number of simulated faults have been introduced. The results suggest that evolutionary repair techniques can improve the process of fault recovery when used instead of or as a supplement to Triple Modular Redundancy (TMR), which is currently the predominant method for mitigating FPGA faults.

  12. Locating Mechanical Damages Using Magnetic Flux Leakage Inspection in Gas Pipeline System

    International Nuclear Information System (INIS)

    Gas transmission pipelines are often inspected and monitored using the magnetic flux leakage method. An inspection vehicle known as a 'pig' is launched into the pipeline and conveyed along the pipe by the pressure of natural gas. The pig contains a magnetizer, an array of sensors and a microprocessor-based data acquisition system for logging data. This paper describes magnetic flux leakage (MFL) signal processing used for detecting mechanical damages during an in-line inspection. The overall approach employs noise removal and clustering technique. The proposed method is computationally efficient and can easily be implemented. Results are presented and verified by field tests from an application of the signal processing

  13. Ultrasonic inspection of inpile tubes

    International Nuclear Information System (INIS)

    The in-service inspection (ISI) of inpile tubes can be performed accurately and safely with a semiautomatic ultrasonic inspection system. The ultrasonic technique uses a set of multiple transducers to detect and size cracks, voids, and laminations radially and circumferentially. Welds are also inspected for defects. The system is designed to inspect stainless steel and Inconel tubes ranging from 53.8 mm (2.12 in.) to 101.6 mm (4 in.) inner diameter with wall thickness on the order of 5 mm. The inspection head contains seven transducers mounted in a surface-following device. Six angle-beam transducers generate shear waves in the tubes. Two of the six are oriented to detect circumferential cracks, and two detect axial cracks. Although each of these four transducers is used in the pulse-echo mode, they are oriented in aligned sets so pitch-catch operation is possible if desired. The remaining angle-beam transducers are angulated to detect flaws that are off axial or circumferential orientation. The seventh transducer is used for longitudinal inspection and detects and sizes laminar-type defects

  14. RBF-based technique for statistical demodulation of pathological tremor.

    Science.gov (United States)

    Gianfelici, Francesco

    2013-10-01

    This paper presents an innovative technique based on the joint approximation capabilities of radial basis function (RBF) networks and the estimation capability of the multivariate iterated Hilbert transform (IHT) for the statistical demodulation of pathological tremor from electromyography (EMG) signals in patients with Parkinson's disease. We define a stochastic model of the multichannel high-density surface EMG by means of the RBF networks applied to the reconstruction of the stochastic process (characterizing the disease) modeled by the multivariate relationships generated by the Karhunen-Loéve transform in Hilbert spaces. Next, we perform a demodulation of the entire random field by means of the estimation capability of the multivariate IHT in a statistical setting. The proposed method is applied to both simulated signals and data recorded from three Parkinsonian patients and the results show that the amplitude modulation components of the tremor oscillation can be estimated with signal-to-noise ratio close to 30 dB with root-mean-square error for the estimates of the tremor instantaneous frequency. Additionally, the comparisons with a large number of techniques based on all the combinations of the RBF, extreme learning machine, backpropagation, support vector machine used in the first step of the algorithm; and IHT, empirical mode decomposition, multiband energy separation algorithm, periodic algebraic separation and energy demodulation used in the second step of the algorithm, clearly show the effectiveness of our technique. These results show that the proposed approach is a potential useful tool for advanced neurorehabilitation technologies that aim at tremor characterization and suppression. PMID:24808594

  15. Semantic-based technique for thai documents plagiarism detection

    Directory of Open Access Journals (Sweden)

    Sorawat Prapanitisatian

    2014-03-01

    Full Text Available Plagiarism is the act of taking another person's writing or idea without referring to the source of information. This is one of major problems in educational institutes. There is a number of plagiarism detection software available on the Internet. However, a few numbers of them works. Typically, they use a simple method for plagiarism detection e.g. string matching. The main weakness of this method is it cannot detect the plagiarism when the author replaces some words using synonyms. As such, this paper presents a new technique for a semantic-based plagiarism detection using Semantic Role Labeling (SRL and term weighting. SRL is deployed in order to calculate the semantic-based similarity. The main different from the existing framework is terms in a sentence are weighted dynamically depending on their roles in the sentence e.g. subject, verb or object. This technique enhances the plagiarism detection mechanism more efficiently than existing system although positions of terms in a sentence are reordered. The experimental results show that the proposed method can detect the plagiarism document more effective than the existing methods, Anti-kobpae, Turnit-in and Traditional Semantic Role Labeling.

  16. Generation of Quasi-Gaussian Pulses Based on Correlation Techniques

    Directory of Open Access Journals (Sweden)

    POHOATA, S.

    2012-02-01

    Full Text Available The Gaussian pulses have been mostly used within communications, where some applications can be emphasized: mobile telephony (GSM, where GMSK signals are used, as well as the UWB communications, where short-period pulses based on Gaussian waveform are generated. Since the Gaussian function signifies a theoretical concept, which cannot be accomplished from the physical point of view, this should be expressed by using various functions, able to determine physical implementations. New techniques of generating the Gaussian pulse responses of good precision are approached, proposed and researched in this paper. The second and third order derivatives with regard to the Gaussian pulse response are accurately generated. The third order derivates is composed of four individual rectangular pulses of fixed amplitudes, being easily to be generated by standard techniques. In order to generate pulses able to satisfy the spectral mask requirements, an adequate filter is necessary to be applied. This paper emphasizes a comparative analysis based on the relative error and the energy spectra of the proposed pulses.

  17. Hash Based Least Significant Bit Technique For Video Steganography

    Directory of Open Access Journals (Sweden)

    Prof. Dr. P. R. Deshmukh ,

    2014-01-01

    Full Text Available The Hash Based Least Significant Bit Technique For Video Steganography deals with hiding secret message or information within a video.Steganography is nothing but the covered writing it includes process that conceals information within other data and also conceals the fact that a secret message is being sent.Steganography is the art of secret communication or the science of invisible communication. In this paper a Hash based least significant bit technique for video steganography has been proposed whose main goal is to embed a secret information in a particular video file and then extract it using a stego key or password. In this Least Significant Bit insertion method is used for steganography so as to embed data in cover video with change in the lower bit.This LSB insertion is not visible.Data hidding is the process of embedding information in a video without changing its perceptual quality. The proposed method involve with two terms that are Peak Signal to Noise Ratio (PSNR and the Mean Square Error (MSE .This two terms measured between the original video files and steganographic video files from all video frames where a distortion is measured using PSNR. A hash function is used to select the particular position for insertion of bits of secret message in LSB bits.

  18. Development of pressure tube inspection equipment for the Fugen (ATR)

    International Nuclear Information System (INIS)

    A remote-controlled in-service inspection device has been developed for inspecting the pressure tubes of the Fugen, which is a heavy-water-moderated, boiling light-water-cooled pressure-tube-type reactor. The equipment is capable of performing three kinds of inspection: ultrasonic flaw detection, measurement of inside diameter and visual inspection of the internal surface. To reduce the radiation exposure of inspectors, the three kinds of detectors, with their associated electronics and drive mechanisms for vertical and rotating movements, are housed in the inspection tool assembly, which can be mounted on or removed from the pressure tubes by remote control using a refuelling machine. The ultrasonic technique has been adopted for measurement of the internal diameter in order to shorten the inspection time. The detectors, TV camera and electronic components used in the inspection tool assembly were selected on the basis of irradiation test results. Before inspection of the Fugen reactor, the total system was tested on a mock-up pressure tube to confirm its functions, performance, durability and reliability. The test results were: (1) the ultrasonic flaw detector can detect an artificial flaw of 2.0 mm in length, 0.1 mm in width and 0.1 mm in depth with S/N=7 dB; (2) the inside diameter measurement system can measure the inside diameter, ranging from 117.5 to 119.5 mm, with an accuracy of +-20 μm; (3) an artificial flaw of 2.0 mm in length, 0.1 mm in width and 0.1 mm in depth can be observed by the internal surface observation system. The equipment was used for the inspection of ten pressure tubes of the Fugen reactor during the May 1984 annual inspection. No degradation of the performance of the equipment was observed even after 55 hours of inspection under a maximum dose rate of 2.5x105 R/h. Based on these results, the functions and performance of the equipment in practical use were fully confirmed. (author)

  19. 在用医疗器械的检验技术要求%Requirements on the Inspection Technique of In-Use Medical Devices

    Institute of Scientific and Technical Information of China (English)

    李澍; 王权; 张艳丽; 任海萍

    2014-01-01

    本文首先介绍了国外医疗器械质量控制现状,然后从安全性、基本性能、生命周期、标准化的器械检测车等四个方面对我国医疗器械检验现状及问题进行分析,并提出相应的意见,以期提高在用医疗器械管理和质量控制水平。%This paper ifrstly introduced the overseas quality control status of medical devices, and then analyzed the current situation and problems of medical devices inspection in China from the perspectives of safety, basic performance, lifecycle and standardized instruments checkout vehicles. Finally, corresponding suggestions were put forward in order to improve the management and quality control levels of in-use medical devices.

  20. 在用医疗器械的检验技术要求%Requirements on the Inspection Technique of In-Use Medical Devices

    Institute of Scientific and Technical Information of China (English)

    李澍; 王权; 张艳丽; 任海萍

    2014-01-01

    This paper ifrstly introduced the overseas quality control status of medical devices, and then analyzed the current situation and problems of medical devices inspection in China from the perspectives of safety, basic performance, lifecycle and standardized instruments checkout vehicles. Finally, corresponding suggestions were put forward in order to improve the management and quality control levels of in-use medical devices.%本文首先介绍了国外医疗器械质量控制现状,然后从安全性、基本性能、生命周期、标准化的器械检测车等四个方面对我国医疗器械检验现状及问题进行分析,并提出相应的意见,以期提高在用医疗器械管理和质量控制水平。