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Sample records for allowable flaw sizes

  1. Determination of Flaw Size from Thermographic Data

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Howell, Patricia A.; Zalameda, Joseph N.

    2014-01-01

    Conventional methods for reducing the pulsed thermographic responses of delaminations tend to overestimate the size of the flaw. Since the heat diffuses in the plane parallel to the surface, the resulting temperature profile over the flaw is larger than the flaw. A variational method is presented for reducing the thermographic data to produce an estimated size for the flaw that is much closer to the true size of the flaw. The size is determined from the spatial thermal response of the exterior surface above the flaw and a constraint on the length of the contour surrounding the flaw. The technique is applied to experimental data acquired on a flat bottom hole composite specimen.

  2. Critical Initial Flaw Size Analysis

    NASA Technical Reports Server (NTRS)

    Dawicke, David S.; Raju, Ivatury S.; Cheston, Derrick J.

    2008-01-01

    An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). The USS consists of several "tuna can" segments that are approximately 216 inches in diameter, 115 inches tall, and 0.5 inches thick. A 6 inch wide by 1 inch thick flange is welded to the skin and is used to fasten adjacent tuna cans. A schematic of a "tuna can" and the location of the flange-to-skin weld are shown in Figure 1. Gussets (shown in yellow in Figure 1) are welded to the skin and flange every 10 degrees around the circumference of the "tuna can". The flange-to-skin weld is a flux core butt weld with a fillet weld on the inside surface, as illustrated in Figure 2. The welding process may create loss of fusion defects in the weld that could develop into fatigue cracks and jeopardize the structural integrity of the Ares I-X vehicle. The CIFS analysis was conducted to determine the largest crack in the weld region that will not grow to failure within 4 lifetimes, as specified by NASA standard 5001 & 5019 [1].

  3. Critical flaw size in silicon nitride ball bearings

    NASA Astrophysics Data System (ADS)

    Levesque, George Arthur

    Aircraft engine and bearing manufacturers have been aggressively pursuing advanced materials technology systems solutions to meet main shaft-bearing needs of advanced military aircraft engines. Ceramic silicon nitride hybrid bearings are being developed for such high performance applications. Though silicon nitride exhibits many favorable properties such as high compressive strength, high hardness, a third of the density of steel, low coefficient of thermal expansion, and high corrosion and temperature resistance, they also have low fracture toughness and are susceptible to failure from fatigue spalls emanating from pre-existing surface flaws that can grow under rolling contact fatigue (RCF). Rolling elements and raceways are among the most demanding components in aircraft engines due to a combination of high cyclic contact stresses, long expected component lifetimes, corrosive environment, and the high consequence of fatigue failure. The cost of these rolling elements increases exponentially with the decrease in allowable flaw size for service applications. Hence the range of 3D non-planar surface flaw geometries subject to RCF is simulated to determine the critical flaw size (CFS) or the largest allowable flaw that does not grow under service conditions. This dissertation is a numerical and experimental investigation of surface flaws in ceramic balls subjected to RCF and has resulted in the following analyses: Crack Shape Determination: the nucleation of surface flaws from ball impact that occurs during the manufacturing process is simulated. By examining the subsurface Hertzian stresses between contacting spheres, their applicability to predicting and characterizing crack size and shape is established. It is demonstrated that a wide range of cone and partial cone cracks, observed in practice, can be generated using the proposed approaches. RCF Simulation: the procedure and concerns in modeling nonplanar 3D cracks subject to RCF using FEA for stress intensity

  4. Residual Stresses and Critical Initial Flaw Size Analyses of Welds

    NASA Technical Reports Server (NTRS)

    Brust, Frederick W.; Raju, Ivatury, S.; Dawocke, David S.; Cheston, Derrick

    2009-01-01

    An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). A series of weld analyses are performed to determine the residual stresses in a critical region of the USS. Weld residual stresses both increase constraint and mean stress thereby having an important effect on the fatigue life. The purpose of the weld analyses was to model the weld process using a variety of sequences to determine the 'best' sequence in terms of weld residual stresses and distortions. The many factors examined in this study include weld design (single-V, double-V groove), weld sequence, boundary conditions, and material properties, among others. The results of this weld analysis are included with service loads to perform a fatigue and critical initial flaw size evaluation.

  5. Technical Letter Report Development of Flaw Size Distribution Tables Including Effects of Flaw Depth Sizing Errors for Draft 10CFR 50.61a (Alternate PTS Rule) JCN-N6398, Task 4

    SciTech Connect

    Simonen, Fredric A.; Gosselin, Stephen R.; Doctor, Steven R.

    2013-04-22

    This document describes a new method to determine whether the flaws in a particular reactor pressure vessel are consistent with the assumptions regarding the number and sizes of flaws used in the analyses that formed the technical justification basis for the new voluntary alternative Pressurized Thermal Shock (PTS) rule (Draft 10 CFR 50.61a). The new methodology addresses concerns regarding prior methodology because ASME Code Section XI examinations do not detect all fabrication flaws, they have higher detection performance for some flaw types, and there are flaw sizing errors always present (e.g., significant oversizing of small flaws and systematic under sizing of larger flaws). The new methodology allows direct comparison of ASME Code Section XI examination results with values in the PTS draft rule Tables 2 and 3 in order to determine if the number and sizes of flaws detected by an ASME Code Section XI examination are consistent with those assumed in the probabilistic fracture mechanics calculations performed in support of the development of 10 CFR 50.61a.

  6. Modeling the X-ray Process, and X-ray Flaw Size Parameter for POD Studies

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2014-01-01

    Nondestructive evaluation (NDE) method reliability can be determined by a statistical flaw detection study called probability of detection (POD) study. In many instances, the NDE flaw detectability is given as a flaw size such as crack length. The flaw is either a crack or behaving like a crack in terms of affecting the structural integrity of the material. An alternate approach is to use a more complex flaw size parameter. The X-ray flaw size parameter, given here, takes into account many setup and geometric factors. The flaw size parameter relates to X-ray image contrast and is intended to have a monotonic correlation with the POD. Some factors such as set-up parameters, including X-ray energy, exposure, detector sensitivity, and material type that are not accounted for in the flaw size parameter may be accounted for in the technique calibration and controlled to meet certain quality requirements. The proposed flaw size parameter and the computer application described here give an alternate approach to conduct the POD studies. Results of the POD study can be applied to reliably detect small flaws through better assessment of effect of interaction between various geometric parameters on the flaw detectability. Moreover, a contrast simulation algorithm for a simple part-source-detector geometry using calibration data is also provided for the POD estimation.

  7. Probabilistic Estimation of Critical Flaw Sizes in the Primary Structure Welds of the Ares I-X Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Pai, Shantaram S.; Hoge, Peter A.; Patel, B. M.; Nagpal, Vinod K.

    2009-01-01

    The primary structure of the Ares I-X Upper Stage Simulator (USS) launch vehicle is constructed of welded mild steel plates. There is some concern over the possibility of structural failure due to welding flaws. It was considered critical to quantify the impact of uncertainties in residual stress, material porosity, applied loads, and material and crack growth properties on the reliability of the welds during its pre-flight and flight. A criterion--an existing maximum size crack at the weld toe must be smaller than the maximum allowable flaw size--was established to estimate the reliability of the welds. A spectrum of maximum allowable flaw sizes was developed for different possible combinations of all of the above listed variables by performing probabilistic crack growth analyses using the ANSYS finite element analysis code in conjunction with the NASGRO crack growth code. Two alternative methods were used to account for residual stresses: (1) The mean residual stress was assumed to be 41 ksi and a limit was set on the net section flow stress during crack propagation. The critical flaw size was determined by parametrically increasing the initial flaw size and detecting if this limit was exceeded during four complete flight cycles, and (2) The mean residual stress was assumed to be 49.6 ksi (the parent material s yield strength) and the net section flow stress limit was ignored. The critical flaw size was determined by parametrically increasing the initial flaw size and detecting if catastrophic crack growth occurred during four complete flight cycles. Both surface-crack models and through-crack models were utilized to characterize cracks in the weld toe.

  8. Flaw Sizing in Pipes Using Long-Range Guided Wave Testing

    NASA Astrophysics Data System (ADS)

    Sanderson, R. M.; Catton, P. P.

    2011-06-01

    The absence of adequate inspection data from difficult-to-access areas on pipelines, such as cased-road crossings, makes determination of fitness for continued service and compliance with increasingly stringent regulatory requirements problematic. Screening for corrosion using long-range guided wave testing is a relatively new inspection technique. The complexity of the possible modes of vibration means the technique can be difficult to implement effectively but this also means that it has great potential for both detecting and characterizing flaws. The ability to determine flaw size would enable the direct application of standard procedures for determining fitness-for-service, such as ASME B31G, RSTRENG, or equivalent for tens of metres of pipeline from a single inspection location. This paper presents a new technique for flaw sizing using guided wave inspection data. The technique has been developed using finite element models and experimentally validated on 6″ Schedule 40 steel pipe. Some basic fitness-for-service assessments have been carried out using the measured values and the maximum allowable operating pressure was accurately determined.

  9. Using a Bayesian Model to Jointly Estimate the Flaw Size Distribution and the Pod Function

    NASA Astrophysics Data System (ADS)

    Li, M.; Meeker, W. Q.; Hovey, P.

    2010-02-01

    In this paper we extend previous work by the authors to jointly estimate the flaw size distribution and the POD function from simulated field inspection data. Similar to our previous work, we assume that when a crack is above a detection threshold, both the signal amplitude and the flaw size are recorded. For a signal that is above the noise floor, but below the detection threshold, only the amplitude is recorded. At all other locations we know only that the signal is below the noise floor, i.e. left censored. Now our model allows different airplanes to have different crack growth rates, and the distribution of crack growth rates is to be estimated from the data. To estimate the parameters of the model, we use a Bayesian formulation that provides a convenient structure for estimating the plane-to-plane differences. The Bayesian formulation also allows the use of prior information based on knowledge of physics or previous experience with similar inspection situations. For example, there may be useful information about crack growth rates and about the slope in the amplitude and crack size relationship. Use of such information can importantly improve estimation precision.

  10. Determination of Flaw Size and Depth From Temporal Evolution of Thermal Response

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Zalameda, Joseph N.; Cramer, Elliott; Howell, Patricia A.

    2015-01-01

    Simple methods for reducing the pulsed thermographic responses of flaws have tended to be based on either the spatial or temporal response. This independent assessment limits the accuracy of characterization. A variational approach is presented for reducing the thermographic data to produce an estimated size for a flaw that incorporates both the temporal and spatial response to improve the characterization. The size and depth are determined from both the temporal and spatial thermal response of the exterior surface above a flaw and constraints on the length of the contour surrounding the delamination. Examples of the application of the technique to simulation and experimental data acquired are presented to investigate the limitations of the technique.

  11. A New Merit Function for Evaluating the Flaw Tolerance of Composite Laminates. Part 2; Arbitrary Size Holes and Center Cracks

    NASA Technical Reports Server (NTRS)

    Martin, Mikulas M., Jr.; Sumpter, Rod

    2000-01-01

    In a previous paper, a new merit function for determining the strength performance of flawed composite laminates was presented. This previous analysis was restricted to circular hole flaws that were large enough that failure could be predicted using the laminate stress concentration factor. In this paper, the merit function is expanded to include the flaw cases of an arbitrary size circular hole or center crack. Failure prediction for these cases is determined using the point stress criterion. An example application of the merit function is included for a wide range of graphite/epoxy laminates.

  12. Reference flaw size for structural and fracture analysis of Types 1 and 2 waste tanks

    SciTech Connect

    Wiersma, B.J.; Sindelar, R.L.

    1994-01-01

    High Level Waste Engineering (HLWE) is reviewing the Technical Standard requirements for tank level and minimum wall temperature. These requirements are necessary to minimize the probability of brittle fracture of the primary liner due to normal operating and/or seismic loads. The review includes the determination of a reference flaw size, a maximum through-wall crack length, which may reasonably be applied to structural and fracture analysis of the Type I and II waste tank primary liners. This memorandum briefly discusses the mechanism of crack initiation and propagation, the inspections of primary wall cracks, and a statistical analysis of the measured crack lengths. Recommendations on additional analyses which may increase the confidence in the reference flaw size will also be presented. The primary liner for Type I and II waste tanks is fabricated from ASTM A285, Grade B carbon steel (A285). The liner received no heat treatments to relieve residual stresses in the heat affected zones. Five Type I waste tanks and all four Type II waste tanks developed through-wall cracks. Leaks developed in tanks 9, 10,14 and 16 within less than two years. Small surface cracks were also observed on the interior of the tank primary. The cracks were perpendicular to the butt welds and extended through the heat affected zone before stopping shortly after penetrating the base metal. The largest leakage of radioactive waste, approximately 185,000 gallons from the primary into the annulus, occurred from Tank 16, a Type II waste tank. During inspections of this tank over 300 leaks were discovered with the longest observed crack being approximately 6 inches. Due to the large number of observed cracks and the amount of leakage, this wag the only tank that was surveyed for crack lengths. For this analysis, Tank 16 will be considered representative of all Type I and II waste tanks because the materials, construction practices, and tank chemistry represented a worst case.

  13. Elastic-Plastic Fracture Mechanics Analysis of Critical Flaw Size in ARES I-X Flange-to-Skin Welds

    NASA Technical Reports Server (NTRS)

    Chell, G. Graham; Hudak, Stephen J., Jr.

    2008-01-01

    NASA's Ares 1 Upper Stage Simulator (USS) is being fabricated from welded A516 steel. In order to insure the structural integrity of these welds it is of interest to calculate the critical initial flaw size (CIFS) to establish rational inspection requirements. The CIFS is in turn dependent on the critical final flaw size (CFS), as well as fatigue flaw growth resulting from transportation, handling and service-induced loading. These calculations were made using linear elastic fracture mechanics (LEFM), which are thought to be conservative because they are based on a lower bound, so called elastic, fracture toughness determined from tests that displayed significant plasticity. Nevertheless, there was still concern that the yield magnitude stresses generated in the flange-to-skin weld by the combination of axial stresses due to axial forces, fit-up stresses, and weld residual stresses, could give rise to significant flaw-tip plasticity, which might render the LEFM results to be non-conservative. The objective of the present study was to employ Elastic Plastic Fracture Mechanics (EPFM) to determine CFS values, and then compare these values to CFS values evaluated using LEFM. CFS values were calculated for twelve cases involving surface and embedded flaws, EPFM analyses with and without plastic shakedown of the stresses, LEFM analyses, and various welding residual stress distributions. For the cases examined, the computed CFS values based on elastic analyses were the smallest in all instances where the failures were predicted to be controlled by the fracture toughness. However, in certain cases, the CFS values predicted by the elastic-plastic analyses were smaller than those predicted by the elastic analyses; in these cases the failure criteria were determined by a breakdown in stress intensity factor validity limits for deep flaws (a greater than 0.90t), rather than by the fracture toughness. Plastic relaxation of stresses accompanying shakedown always increases the

  14. Quantitative flaw characterization with ultrasonic phased arrays

    NASA Astrophysics Data System (ADS)

    Engle, Brady John

    Ultrasonic nondestructive evaluation (NDE) is a critical diagnostic tool in many industries. It is used to characterize potentially dangerous flaws in critical components for aerospace, automotive, and energy applications. The use of phased array transducers allows for the extension of traditional techniques and the introduction of new methods for quantitative flaw characterization. An equivalent flaw sizing technique for use in time-of-flight diffraction setups is presented that provides an estimate of the size and orientation of isolated cracks, surface-breaking cracks, and volumetric flaws such as voids and inclusions. Experimental validation is provided for the isolated crack case. A quantitative imaging algorithm is developed that corrects for system effects and wave propagation, making the images formed directly related to the properties of the scatterer present. Simulated data is used to form images of cylindrical and spherical inclusions. The contributions of different signals to the image formation process are discussed and examples of the quantitative nature of the images are shown.

  15. Ultrasonic Phased Array Technique for Accurate Flaw Sizing in Dissimilar Metal Welds

    SciTech Connect

    Jonathan D Buttram

    2005-03-11

    Described is a manual,portable non-destructive technique to determine the through wall height of cracks present in dissimilar metal welds used in the primary coolling systems of pressure water and boiler light water reactors. Current manual methods found in industry have proven not to exhibit the sizing accuracy required by ASME inspection requirement. The technique described demonstrated an accuracy approximately three times that required to ASME Section XI, Appendix 8 qualification.

  16. Quantifying Flaw Characteristics from IR NDE Data

    SciTech Connect

    Miller, W; Philips, N R; Burke, M W; Robbins, C L

    2003-02-14

    Work is presented which allows flaw characteristics to be quantified from the transient IR NDE signature. The goal of this effort was to accurately determine the type, size and depth of flaws revealed with IR NDE, using sonic IR as the example IR NDE technique. Typically an IR NDE experiment will result in a positive qualitative indication of a flaw such as a cold or hot spot in the image, but will not provide quantitative data thereby leaving the practitioner to make educated guesses as to the source of the signal. The technique presented here relies on comparing the transient IR signature to exact heat transfer analytical results for prototypical flaws, using the flaw characteristics as unknown fitting parameters. A nonlinear least squares algorithm is used to evaluate the fitting parameters, which then provide a direct measure of the flaw characteristics that can be mapped to the imaged surface for visual reference. The method uses temperature data for the heat transfer analysis, so radiometric calibration of the IR signal is required. The method provides quantitative data with a single thermal event (e.g. acoustic pulse or flash), as compared to phase-lock techniques that require many events. The work has been tested with numerical data but remains to be validated by experimental data, and that effort is underway.

  17. Ares I-X Upper Stage Simulator Structural Analyses Supporting the NESC Critical Initial Flaw Size Assessment

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Phillips, Dawn R.; Raju, Ivatury S.

    2008-01-01

    The structural analyses described in the present report were performed in support of the NASA Engineering and Safety Center (NESC) Critical Initial Flaw Size (CIFS) assessment for the ARES I-X Upper Stage Simulator (USS) common shell segment. The structural analysis effort for the NESC assessment had three thrusts: shell buckling analyses, detailed stress analyses of the single-bolt joint test; and stress analyses of two-segment 10 degree-wedge models for the peak axial tensile running load. Elasto-plastic, large-deformation simulations were performed. Stress analysis results indicated that the stress levels were well below the material yield stress for the bounding axial tensile design load. This report also summarizes the analyses and results from parametric studies on modeling the shell-to-gusset weld, flange-surface mismatch, bolt preload, and washer-bearing-surface modeling. These analyses models were used to generate the stress levels specified for the fatigue crack growth assessment using the design load with a factor of safety.

  18. Modeling the Effects of Beam Size and Flaw Morphology on Ultrasonic Pulse/Echo Sizing of Delaminations in Carbon Composites

    NASA Technical Reports Server (NTRS)

    Margetan, Frank J.; Leckey, Cara A.; Barnard, Dan

    2012-01-01

    The size and shape of a delamination in a multi-layered structure can be estimated in various ways from an ultrasonic pulse/echo image. For example the -6dB contours of measured response provide one simple estimate of the boundary. More sophisticated approaches can be imagined where one adjusts the proposed boundary to bring measured and predicted UT images into optimal agreement. Such approaches require suitable models of the inspection process. In this paper we explore issues pertaining to model-based size estimation for delaminations in carbon fiber reinforced laminates. In particular we consider the influence on sizing when the delamination is non-planar or partially transmitting in certain regions. Two models for predicting broadband sonic time-domain responses are considered: (1) a fast "simple" model using paraxial beam expansions and Kirchhoff and phase-screen approximations; and (2) the more exact (but computationally intensive) 3D elastodynamic finite integration technique (EFIT). Model-to-model and model-to experiment comparisons are made for delaminations in uniaxial composite plates, and the simple model is then used to critique the -6dB rule for delamination sizing.

  19. Individual increase in inbreeding allows estimating effective sizes from pedigrees

    PubMed Central

    Gutiérrez, Juan Pablo; Cervantes, Isabel; Molina, Antonio; Valera, Mercedes; Goyache, Félix

    2008-01-01

    We present here a simple approach to obtain reliable estimates of the effective population size in real world populations via the computation of the increase in inbreeding for each individual (delta Fi) in a given population. The values of delta Fi are computed as t-root of 1 - (1 - Fi) where Fi is the inbreeding coefficient and t is the equivalent complete generations for each individual. The values of delta F computed for a pre-defined reference subset can be averaged and used to estimate effective size. A standard error of this estimate of Ne can be further computed from the standard deviation of the individual increase in inbreeding. The methodology is demonstrated by applying it to several simulated examples and to a real pedigree in which other methodologies fail when considering reference subpopulations. The main characteristics of the approach and its possible use are discussed both for predictive purposes and for analyzing genealogies. PMID:18558071

  20. Flaw detection and evaluation

    SciTech Connect

    Wilks, Robert S.; Sturges, Jr., Robert H.

    1983-01-01

    The invention provides a method of and apparatus for optically inspecting nuclear fuel pellets for surface flaws. The inspection system includes a prism and lens arrangement for scanning the surface of each pellet as the same is rotated. The resulting scan produces data indicative of the extent and shape of each flaw which is employed to generate a flaw quality index for each detected flaw. The flaw quality indexes from all flaws are summed and compared with an acceptable surface quality index. The result of the comparison is utilized to control the acceptance or rejection of the pellet.

  1. Currency flaw severity. [Banknotes

    SciTech Connect

    Johnson, C.; Burnett, M.; Goodman, C.; Sherrod, R.; Schmoyer, R.; Harrison, C.; Uppuluri, R.

    1986-01-01

    A survey of currency flaw severity was carried out using 300 banknotes and 37 judges. Each judge assigned each note to one of five flaw severity categories. These categories correspond to severity grades of 1 to 5 with 1 equivalent to ''always accepted'' and 5 ''never accepted.'' An average flaw severity grade for each note was obtained by taking the mean of the severity grades assigned to that note by the 37 judges. Thus, each note has a single numerical real-number flaw grade between 1 and 5. Mathematical modeling of the currency flaw survey results is continuing with some very promising initial results. Our present model handles common excess ink and missing ink flaw types quite well. We plan to extend the model to ink level, mash, setoff and blanket impression flaw types.

  2. The HMDS Coating Flaw Removal Tool

    SciTech Connect

    Monticelli, M V; Nostrand, M C; Mehta, N; Kegelmeyer, L; Johnson, M A; Fair, J; Widmayer, C

    2008-10-24

    In many high energy laser systems, optics with HMDS sol gel antireflective coatings are placed in close proximity to each other making them particularly susceptible to certain types of strong optical interactions. During the coating process, halo shaped coating flaws develop around surface digs and particles. Depending on the shape and size of the flaw, the extent of laser light intensity modulation and consequent probability of damaging downstream optics may increase significantly. To prevent these defects from causing damage, a coating flaw removal tool was developed that deploys a spot of decane with a syringe and dissolves away the coating flaw. The residual liquid is evacuated leaving an uncoated circular spot approximately 1mm in diameter. The resulting uncoated region causes little light intensity modulation and thus has a low probability of causing damage in optics downstream from the mitigated flaw site.

  3. Flaw detection by spatially coded backscatter radiography.

    PubMed

    Thangavelu, Sivakumar; Hussein, Esam M A

    2007-02-01

    Backscatter imaging is useful for inspecting structures that are accessible only from one side. However, indications provided by scattered radiation are typically weak, convoluted and difficult to interpret. This paper explores the use of the coded aperture technique to detect flaws using gamma-ray backscatter imaging. The viability of this approach is demonstrated with indications obtained from Monte Carlo simulations of radiation scattering measurements. The results show that, with a 2 mm wide beam of 137Cs photons, flaws as small as 1.5 mm in width can be detected using this technique. Indications of changes in flaw size, location, multiplicity and density were also observable. In addition, it is possible to quantify, from the decoded indications, the flaw location and its size.

  4. Automatic inspection technique for optical surface flaws

    NASA Astrophysics Data System (ADS)

    Yang, GuoGuang; Gao, Wenliang; Cheng, Shangyi

    1991-01-01

    Industrial inspection of optical component surface flaws requires objective, high efficient and fast measurement methods and instruments. In this paper, a novel method, which is practical for on- line inspecting optical component surface flaws in manufacturing industry, is discribed. Laser beam goes through a lean- placed mirror with a slot in center onto the surface of the specimen. The imformation of surface flaws is obtained through analysing the frequency spectrum of reflective light which is detected by a photomultiplier, the specimen scanning control and signal processing are finished by a low - cost and handy single- board microcomputer. The theory that applies the scanning frequency spectrum method , the method for determining flaw size and measuring sensitivity as well as control model for various specimen are analysed in detail .A system has been built according to the idea discribed above. By using the system, several specimen are measured, the comparison and analysis between exprimental results and actual flaw conditions are given. The minimum detectable flaw is 3 micrometer, the measuring error is also given.

  5. In-service Inspection Ultrasonic Testing of Reactor Pressure Vessel Welds for Assessing Flaw Density and Size Distribution per 10 CFR 50.61a, Alternate Fracture Toughness Requirements

    SciTech Connect

    Sullivan, Edmund J.; Anderson, Michael T.; Norris, Wallace

    2012-09-17

    Pressurized thermal shock (PTS) events are system transients in a pressurized water reactor (PWR) in which there is a rapid operating temperature cool-down that results in cold vessel temperatures with or without repressurization of the vessel. The rapid cooling of the inside surface of the reactor pressure vessel (RPV) causes thermal stresses that can combine with stresses caused by high pressure. The aggregate effect of these stresses is an increase in the potential for fracture if a pre-existing flaw is present in a material susceptible to brittle failure. The ferritic, low alloy steel of the reactor vessel beltline adjacent to the core, where neutron radiation gradually embrittles the material over the lifetime of the plant, can be susceptible to brittle fracture. The PTS rule, described in the Code of Federal Regulations, Title 10, Section 50.61 (§50.61), “Fracture Toughness Requirements for Protection against Pressurized Thermal Shock Events,” adopted on July 23, 1985, establishes screening criteria to ensure that the potential for a reactor vessel to fail due to a PTS event is deemed to be acceptably low. The U.S. Nuclear Regulatory Commission (NRC) completed a research program that concluded that the risk of through-wall cracking due to a PTS event is much lower than previously estimated. The NRC subsequently developed a rule, §50.61a, published on January 4, 2010, entitled “Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events” (75 FR 13). Use of the new rule by licensees is optional. The §50.61a rule differs from §50.61 in that it requires licensees who choose to follow this alternate method to analyze the results from periodic volumetric examinations required by the ASME Code, Section XI, Rules for Inservice Inspection (ISI) of Nuclear Power Plants. These analyses are intended to determine if the actual flaw density and size distribution in the licensee’s reactor vessel beltline welds are bounded

  6. Quantitative flaw characterization with scanning laser acoustic microscopy

    NASA Technical Reports Server (NTRS)

    Generazio, E. R.; Roth, D. J.

    1986-01-01

    Surface roughness and diffraction are two factors that have been observed to affect the accuracy of flaw characterization with scanning laser acoustic microscopy. In accuracies can arise when the surface of the test sample is acoustically rough. It is shown that, in this case, Snell's law is no longer valid for determining the direction of sound propagation within the sample. The relationship between the direction of sound propagation within the sample, the apparent flaw depth, and the sample's surface roughness is investigated. Diffraction effects can mask the acoustic images of minute flaws and make it difficult to establish their size, depth, and other characteristics. It is shown that for Fraunhofer diffraction conditions the acoustic image of a subsurface defect corresponds to a two-dimensional Fourier transform. Transforms based on simulated flaws are used to infer the size and shape of the actual flaw.

  7. Quantitative flaw characterization with scanning laser acoustic microscopy

    NASA Technical Reports Server (NTRS)

    Generazio, E. R.; Roth, D. J.

    1986-01-01

    Surface roughness and diffraction are two factors that have been observed to affect the accuracy of flaw characterization with scanning laser acoustic microscopy. Inaccuracies can arise when the surface of the test sample is acoustically rough. It is shown that, in this case, Snell's law is no longer valid for determining the direction of sound propagation within the sample. The relationship between the direction of sound propagation within the sample, the apparent flaw depth, and the sample's surface roughness is investigated. Diffraction effects can mask the acoustic images of minute flaws and make it difficult to establish their size, depth, and other characteristics. It is shown that for Fraunhofer diffraction conditions the acoustic image of a subsurface defect corresponds to a two-dimensional Fourier transform. Transforms based on simulated flaws are used to infer the size and shape of the actual flaw.

  8. Estimating probable flaw distributions in PWR steam generator tubes

    SciTech Connect

    Gorman, J.A.; Turner, A.P.L.

    1997-02-01

    This paper describes methods for estimating the number and size distributions of flaws of various types in PWR steam generator tubes. These estimates are needed when calculating the probable primary to secondary leakage through steam generator tubes under postulated accidents such as severe core accidents and steam line breaks. The paper describes methods for two types of predictions: (1) the numbers of tubes with detectable flaws of various types as a function of time, and (2) the distributions in size of these flaws. Results are provided for hypothetical severely affected, moderately affected and lightly affected units. Discussion is provided regarding uncertainties and assumptions in the data and analyses.

  9. GFR normalized to total body water allows comparisons across genders and body sizes.

    PubMed

    Eriksen, Bjørn O; Melsom, Toralf; Mathisen, Ulla D; Jenssen, Trond G; Solbu, Marit D; Toft, Ingrid

    2011-08-01

    The normalization of GFR to a standardized body-surface area of 1.73 m(2) impedes comparison of GFR across individuals of different genders, heights, or weights. Ideally, GFR should be normalized to a parameter that best explains variation in GFR. Here, we measured true GFR by iohexol clearance in a representative sample of 1627 individuals from the general population who did not have diabetes, cardiovascular disease, or kidney disease. We also estimated total body water (TBW), extracellular fluid volume, lean body mass, liver volume, metabolic rate, and body-surface area. We compared two methods of normalizing GFR to these physiologic variables: (1) the conventional method of scaling GFR to each physiologic variable by simple division and (2) a method based on regression of the GFR on each variable. TBW explained a higher proportion of the variation in GFR than the other physiologic variables. GFR adjusted for TBW by the regression method exhibited less dependence on gender, height, and weight compared with the other physiologic variables. Thus, adjusting GFR for TBW by the regression method allows direct comparisons between individuals of different genders, weights, and heights. We propose that regression-based normalization of GFR to a standardized TBW of 40 L should replace the current practice of normalizing GFR to 1.73 m(2) of body-surface area.

  10. Nutrient reserves may allow for genome size increase: evidence from comparison of geophytes and their sister non-geophytic relatives

    PubMed Central

    Veselý, Pavel; Bureš, Petr; Šmarda, Petr

    2013-01-01

    Background and Aims The genome size of an organism is determined by its capacity to tolerate genome expansion, given the species' life strategy and the limits of a particular environment, and the ability for retrotransposon suppression and/or removal. In some giant-genomed bulb geophytes, this tolerance is explained by their ability to pre-divide cells in the dormant stages or by the selective advantage of larger cells in the rapid growth of their fleshy body. In this study, a test shows that the tendency for genome size expansion is a more universal feature of geophytes, and is a subject in need of more general consideration. Methods Differences in monoploid genome sizes were compared using standardized phylogenetically independent contrasts in 47 sister pairs of geophytic and non-geophytic taxa sampled across all the angiosperms. The genome sizes of 96 species were adopted from the literature and 53 species were newly measured using flow cytometry with propidium iodide staining. Key Results The geophytes showed increased genome sizes compared with their non-geophytic relatives, regardless of the storage organ type and regardless of whether or not vernal geophytes, polyploids or annuals were included in the analyses. Conclusions The universal tendency of geophytes to possess a higher genome size suggests the presence of a universal mechanism allowing for genome expansion. It is assumed that this is primarily due to the nutrient and energetic independence of geophytes perhaps allowing continuous synthesis of DNA, which is known to proceed in the extreme cases of vernal geophytes even in dormant stages. This independence may also be assumed as a reason for allowing large genomes in some parasitic plants, as well as the nutrient limitation of small genomes of carnivorous plants. PMID:23960044

  11. Spectroscopic metrics allow in situ measurement of mean size and thickness of liquid-exfoliated few-layer graphene nanosheets.

    PubMed

    Backes, Claudia; Paton, Keith R; Hanlon, Damien; Yuan, Shengjun; Katsnelson, Mikhail I; Houston, James; Smith, Ronan J; McCloskey, David; Donegan, John F; Coleman, Jonathan N

    2016-02-21

    Liquid phase exfoliation is a powerful and scalable technique to produce defect-free mono- and few-layer graphene. However, samples are typically polydisperse and control over size and thickness is challenging. Notably, high throughput techniques to measure size and thickness are lacking. In this work, we have measured the extinction, absorption, scattering and Raman spectra for liquid phase exfoliated graphene nanosheets of various lateral sizes (90 ≤ 〈L〉 ≤ 810 nm) and thicknesses (2.7 ≤ 〈N〉 ≤ 10.4). We found all spectra to show well-defined dependences on nanosheet dimensions. Measurements of extinction and absorption spectra of nanosheet dispersions showed both peak position and spectral shape to vary with nanosheet thickness in a manner consistent with theoretical calculations. This allows the development of empirical metrics to extract the mean thickness of liquid dispersed nanosheets from an extinction (or absorption) spectrum. While the scattering spectra depended on nanosheet length, poor signal to noise ratios made the resultant length metric unreliable. By analyzing Raman spectra measured on graphene nanosheet networks, we found both the D/G intensity ratio and the width of the G-band to scale with mean nanosheet length allowing us to establish quantitative relationships. In addition, we elucidate the variation of 2D/G band intensities and 2D-band shape with the mean nanosheet thickness, allowing us to establish quantitative metrics for mean nanosheet thickness from Raman spectra.

  12. Effects of group size and floor space allowance on grouped sows: aggression, stress, skin injuries, and reproductive performance.

    PubMed

    Hemsworth, P H; Rice, M; Nash, J; Giri, K; Butler, K L; Tilbrook, A J; Morrison, R S

    2013-10-01

    A total of 3,120 sows, in 4 time replicates, were used to determine the effects of group size and floor space on sow welfare using behavioral, physiological, health, and fitness variables. Within 1 to 7 d postinsemination, sows were assigned randomly to treatments of a 3 by 6 factorial arrangement, with 3 group sizes (10, 30, or 80 sows/pen) and 6 floor space allowances (1.4, 1.8, 2.0, 2.2, 2.4, or 3.0 m(2)/sow). Sows were housed on partially slatted concrete floors, and overhead feeders delivered 4 times/day to provide a total of 2.5 kg of feed/sow. As pen space increased from 1.4 to 3.0 m(2)/sow, aggression at feeding decreased from about 9 to 7 bouts/sow (linear, P = 0.029) and plasma cortisol concentrations decreased from about 28 to 21 ng/mL (linear, P = 0.0089) at 2 d. Although the results are in accord with a linear decline from 1.4 to 3 m(2)/sow, the results are also in accord with a decline in these measurements from 1.4 to 1.8 m(2)/sow and no further decline greater than 1.8 m(2)/sow. Farrowing rate (percentage of inseminated sows that farrowed) also increased from about 60 to 75% as space increased from 1.4 to 3.0 m(2)/sow (linear, P = 0.012). Group size was related to skin injuries on d 9 (P = 0.0017), 23 (P = 0.0046), and 51 (P = 0.0006), with groups of 10 consistently having the lowest number of total injuries over this period. Based on the aggression and cortisol results, it is credible to judge that, within the range of floor space allowances studied, sow welfare improves with increased space. However, from a sow welfare perspective, the experiment had insufficient precision to determine what is an adequate space allowance for sows. Thus, although the results definitely support a space allowance of 1.4 m(2)/sow being too small, it is not possible to give guidance on an actual space allowance at mixing that is adequate. PMID:23893983

  13. Combined use of leaf size and economics traits allows direct comparison of hydrophyte and terrestrial herbaceous adaptive strategies

    PubMed Central

    Pierce, Simon; Brusa, Guido; Sartori, Matteo; Cerabolini, Bruno E. L.

    2012-01-01

    Background and Aims Hydrophytes generally exhibit highly acquisitive leaf economics. However, a range of growth forms is evident, from small, free-floating and rapidly growing Lemniden to large, broad-leaved Nymphaeiden, denoting variability in adaptive strategies. Traits used to classify adaptive strategies in terrestrial species, such as canopy height, are not applicable to hydrophytes. We hypothesize that hydrophyte leaf size traits and economics exhibit sufficient overlap with terrestrial species to allow a common classification of plant functional types, sensu Grime's CSR theory. Methods Leaf morpho-functional traits were measured for 61 species from 47 water bodies in lowland continental, sub-alpine and alpine bioclimatic zones in southern Europe and compared against the full leaf economics spectrum and leaf size range of terrestrial herbs, and between hydrophyte growth forms. Key Results Hydrophytes differed in the ranges and mean values of traits compared with herbs, but principal components analysis (PCA) demonstrated that both groups shared axes of trait variability: PCA1 encompassed size variation (area and mass), and PCA2 ranged from relatively dense, carbon-rich leaves to nitrogen-rich leaves of high specific leaf area (SLA). Most growth forms exhibited trait syndromes directly equivalent to herbs classified as R adapted, although Nymphaeiden ranged between C and SR adaptation. Conclusions Our findings support the hypothesis that hydrophyte adaptive strategy variation reflects fundamental trade-offs in economics and size that govern all plants, and that hydrophyte adaptive strategies can be directly compared with terrestrial species by combining leaf economics and size traits. PMID:22337079

  14. Grounding Moralism: Moral Flaws and Aesthetic Properties

    ERIC Educational Resources Information Center

    Smuts, Aaron

    2011-01-01

    Can moral flaws lessen an artwork's aesthetic value? Answering yes to this question requires both that artworks can be morally flawed and that moral flaws within a work of art can have an aesthetic impact. For present purposes, the author will assume that artworks can be morally flawed by such means as endorsing immoral perspectives, culpably…

  15. Deep flaws in weldments of aluminum and titanium

    NASA Technical Reports Server (NTRS)

    Masters, J. N.; Engstrom, W. L.; Bixler, W. D.

    1974-01-01

    Surface flawed specimens of 2219-T87 and 6Al-4V STA titanium weldments were tested to determine static failure modes, failure strength, and fatigue flaw growth characteristics. Thicknesses selected for this study were purposely set at values where, for most test conditions, abrupt instability of the flaw at fracture would not be expected. Static tests for the aluminum weldments were performed at room, LN2 and LH2 temperatures. Titanium static tests for tests were performed at room and LH2 temperatures. Results of the static tests were used to plot curves relating initial flaw size to leakage- or failure-stresses (i.e. "failure" locus curves). Cyclic tests, for both materials, were then performed at room temperature, using initial flaws only slightly below the previously established failure locus for typical proof stress levels. Cyclic testing was performed on pairs of specimens, one with and one without a simulated proof test cycle. Comparisons were made then to determine the value and effect of proof testing as affected by the various variables of proof and operating stress, flaw shape, material thickness, and alloy.

  16. Classification of flaw severity using pattern recognition for guided wave-based structural health monitoring.

    PubMed

    Miller, Corey A; Hinders, Mark K

    2014-01-01

    In this paper, the authors present a formal classification routine to characterize flaw severity in an aircraft-grade aluminum plate using Lamb waves. A rounded rectangle flat-bottom hole is incrementally introduced into the plate, and at each depth multi-mode Lamb wave signals are collected to study the changes in received signal due to mode conversion and scattering from the flaw. Lamb wave tomography reconstructions are used to locate and size the flaw at each depth, however information about the severity of the flaw is obscured when the flaw becomes severe enough that scattering effects dominate. The dynamic wavelet fingerprint is then used to extract features from the raw Lamb wave signals, and supervised pattern classification techniques are used to identify flaw severity with up to 80.7% accuracy for a training set and up to 51.7% accuracy on a series of validation data sets extracted from independent plate samples. PMID:23731948

  17. Classification of flaw severity using pattern recognition for guided wave-based structural health monitoring.

    PubMed

    Miller, Corey A; Hinders, Mark K

    2014-01-01

    In this paper, the authors present a formal classification routine to characterize flaw severity in an aircraft-grade aluminum plate using Lamb waves. A rounded rectangle flat-bottom hole is incrementally introduced into the plate, and at each depth multi-mode Lamb wave signals are collected to study the changes in received signal due to mode conversion and scattering from the flaw. Lamb wave tomography reconstructions are used to locate and size the flaw at each depth, however information about the severity of the flaw is obscured when the flaw becomes severe enough that scattering effects dominate. The dynamic wavelet fingerprint is then used to extract features from the raw Lamb wave signals, and supervised pattern classification techniques are used to identify flaw severity with up to 80.7% accuracy for a training set and up to 51.7% accuracy on a series of validation data sets extracted from independent plate samples.

  18. Digital ultrasonics signal processing: Flaw data post processing use and description

    NASA Astrophysics Data System (ADS)

    Buel, V. E.

    1981-09-01

    A modular system composed of two sets of tasks which interprets the flaw data and allows compensation of the data due to transducer characteristics is described. The hardware configuration consists of two main units. A DEC LSI-11 processor running under the RT-11 sngle job, version 2C-02 operating system, controls the scanner hardware and the ultrasonic unit. A DEC PDP-11/45 processor also running under the RT-11, version 2C-02, operating system, stores, processes and displays the flaw data. The software developed the Ultrasonics Evaluation System, is divided into two catagories; transducer characterization and flaw classification. Each category is divided further into two functional tasks: a data acquisition and a postprocessor ask. The flaw characterization collects data, compresses its, and writes it to a disk file. The data is then processed by the flaw classification postprocessing task. The use and operation of a flaw data postprocessor is described.

  19. Digital ultrasonics signal processing: Flaw data post processing use and description

    NASA Technical Reports Server (NTRS)

    Buel, V. E.

    1981-01-01

    A modular system composed of two sets of tasks which interprets the flaw data and allows compensation of the data due to transducer characteristics is described. The hardware configuration consists of two main units. A DEC LSI-11 processor running under the RT-11 sngle job, version 2C-02 operating system, controls the scanner hardware and the ultrasonic unit. A DEC PDP-11/45 processor also running under the RT-11, version 2C-02, operating system, stores, processes and displays the flaw data. The software developed the Ultrasonics Evaluation System, is divided into two catagories; transducer characterization and flaw classification. Each category is divided further into two functional tasks: a data acquisition and a postprocessor ask. The flaw characterization collects data, compresses its, and writes it to a disk file. The data is then processed by the flaw classification postprocessing task. The use and operation of a flaw data postprocessor is described.

  20. Flawed Items in Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Potenza, Maria T.; Stocking, Martha L.

    A multiple choice test item is identified as flawed if it has no single best answer. In spite of extensive quality control procedures, the administration of flawed items to test-takers is inevitable. Common strategies for dealing with flawed items in conventional testing, grounded in the principle of fairness to test-takers, are reexamined in the…

  1. Flaw imaging and ultrasonic techniques for characterizing sintered silicon carbide

    NASA Technical Reports Server (NTRS)

    Baaklini, George Y.; Abel, Phillip B.

    1987-01-01

    The capabilities were investigated of projection microfocus x-radiography, ultrasonic velocity and attenuation, and reflection scanning acoustic microscopy for characterizing silicon carbide specimens. Silicon carbide batches covered a range of densities and different microstructural characteristics. Room temperature, four point flexural strength tests were conducted. Fractography was used to identify types, sizes, and locations of fracture origins. Fracture toughness values were calculated from fracture strength and flaw characterization data. Detection capabilities of radiography and acoustic microscopy for fracture-causing flaws were evaluated. Applicability of ultrasonics for verifying material strength and toughness was examined.

  2. Ultrasonographic Detection of Tooth Flaws

    NASA Astrophysics Data System (ADS)

    Bertoncini, C. A.; Hinders, M. K.; Ghorayeb, S. R.

    2010-02-01

    The goal of our work is to adapt pulse-echo ultrasound into a high resolution imaging modality for early detection of oral diseases and for monitoring treatment outcome. In this talk we discuss our preliminary results in the detection of: demineralization of the enamel and dentin, demineralization or caries under and around existing restorations, caries on occlusal and interproximal surfaces, cracks of enamel and dentin, calculus, and periapical lesions. In vitro immersion tank experiments are compared to results from a handpiece which uses a compliant delay line to couple the ultrasound to the tooth surface. Because the waveform echoes are complex, and in order to make clinical interpretation of ultrasonic waveform data in real time, it is necessary to automatically interpret the signals. We apply the dynamic wavelet fingerprint algorithms to identify and delineate echographic features that correspond to the flaws of interest in teeth. The resulting features show a clear distinction between flawed and unflawed waveforms collected with an ultrasonic handpiece on both phantom and human cadaver teeth.

  3. Minimization of bacterial size allows for complement evasion and is overcome by the agglutinating effect of antibody

    PubMed Central

    Dalia, Ankur B.; Weiser, Jeffrey N.

    2011-01-01

    SUMMARY The complement system, which functions by lysing pathogens directly or by promoting their uptake by phagocytes, is critical for controlling many microbial infections. Here we show that in Streptococcus pneumoniae, increasing bacterial chain length sensitizes this pathogen to complement deposition and subsequent uptake by human neutrophils. Consistent with this, we show that minimizing chain length provides wild-type bacteria with a competitive advantage in vivo in a model of systemic infection. Investigating how the host overcomes this virulence strategy, we find that antibody promotes complement-dependent opsonophagocytic killing of Streptococcus pneumoniae and lysis of Haemophilus influenzae independent of Fc-mediated effector functions. Consistent with the agglutinating effect of antibody, F(ab′)2 but not Fab could promote this effect. Therefore, increasing pathogen size, whether by natural changes in cellular morphology or via antibody-mediated agglutination, promotes complement-dependent killing. These observations have broad implications for how cell size and morphology can affect virulence among pathogenic microbes. PMID:22100164

  4. Flawed Items in Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Potenza, Maria T.; Stocking, Martha L.

    1997-01-01

    Common strategies for dealing with flawed items in conventional testing, grounded in principles of fairness to examinees, are re-examined in the context of adaptive testing. The additional strategy of retesting from a pool cleansed of flawed items is found, through a Monte Carlo study, to bring about no practical improvement. (SLD)

  5. Coupled resonances allow studying the aging of adhesive contacts between a QCM surface and single, micrometer-sized particles

    NASA Astrophysics Data System (ADS)

    Peschel, Astrid; Langhoff, Arne; Johannsmann, Diethelm

    2015-12-01

    Interparticle contacts and contacts between particles and surfaces are known to change over time. The contact area, the contact stiffness, and the contact strength usually increase as the contact ages. Contact aging is mostly driven by capillary forces, but also by plastic deformation. Making use of acoustic resonators, we have studied the stiffness of contacts between the surface of a quartz crystal microbalance (QCM) and individual, micrometer-sized particles adsorbed to the resonator surface. Studying single particles avoids ensemble-averaging. Central to the analysis is the coupled resonance, occurring when a surface-attached particle together with the link forms a resonator of its own. If the frequency of this second resonator comes close to one of the crystal’s overtones, plots of shifts in resonance bandwidth versus overtone order display a resonance curve. This secondary resonance is caused by the coupling between the particle’s resonance and the main resonance. One can read the frequency of the coupled resonance from this plot. Similarly, resonance curves are observed in plots of frequency and bandwidth versus time, if the contact stiffness varies smoothly with time. Because the coupled resonance is a characteristic feature, it is easily identified even in cases where frequency shifts of some other origin are superimposed onto the data. For the cases studied here, the links stiffened while they dried. Interestingly, the efficiency of coupling between the particle resonance and the main resonance decreased at the same time. This can be explained with an increase in the link’s bending stiffness. The analysis highlights that a QCM experiment amounts to vibrational spectroscopy on surface-attached particles. Among the application examples is the adsorption and drying of a lycopodium spore. Clearly, the technique is also applicable to problems of bioadhesion.

  6. Does prey size matter? Novel observations of feeding in the leatherback turtle (Dermochelys coriacea) allow a test of predator-prey size relationships.

    PubMed

    Fossette, Sabrina; Gleiss, Adrian C; Casey, James P; Lewis, Andrew R; Hays, Graeme C

    2012-06-23

    Optimal foraging models predict that large predators should concentrate on large prey in order to maximize their net gain of energy intake. Here, we show that the largest species of sea turtle, Dermochelys coriacea, does not strictly adhere to this general pattern. Field observations combined with a theoretical model suggest that a 300 kg leatherback turtle would meet its energetic requirements by feeding for 3-4 h a day on 4 g jellyfish, but only if prey were aggregated in high-density patches. Therefore, prey abundance rather than prey size may, in some cases, be the overriding parameter for foraging leatherbacks. This is a classic example where the presence of small prey in the diet of a large marine predator may reflect profitable foraging decisions if the relatively low energy intake per small individual prey is offset by high encounter rates and minimal capture and handling costs. This study provides, to our knowledge, the first quantitative estimates of intake rate for this species. PMID:22090203

  7. Lifetime Predictions of a Titanium Silicate Glass with Machined Flaws

    NASA Technical Reports Server (NTRS)

    Tucker, Dennis S.; Nettles, Alan T.; Cagle, Holly

    2003-01-01

    A dynamic fatigue study was performed on a Titanium Silicate glass to assess its susceptibility to delayed failure and to compare the results with those of a previous study. Fracture mechanics techniques were used to analyze the results for the purpose of making lifetime predictions. The material strength and lifetime was seen to increase due to the removal of residual stress through grinding and polishing. Influence on time-to-failure is addressed for the case with and without residual stress present. Titanium silicate glass otherwise known as ultra-low expansion (ULE)* glass is a candidate for use in applications requiring low thermal expansion characteristics such as telescope mirrors. The Hubble Space Telescope s primary mirror was manufactured from ULE glass. ULE contains 7.5% titanium dioxide which in combination with silica results in a homogenous glass with a linear expansion coefficient near zero. delayed failure . This previous study was based on a 230/270 grit surface. The grinding and polishing process reduces the surface flaw size and subsurface damage, and relieves residual stress by removing the material with successively smaller grinding media. This results in an increase in strength of the optic during the grinding and polishing sequence. Thus, a second study was undertaken using samples with a surface finish typically achieved for mirror elements, to observe the effects of surface finishing on the time-to-failure predictions. An allowable stress can be calculated for this material based upon modulus of rupture data; however, this does not take into account the problem of delayed failure, most likely due to stress corrosion, which can significantly shorten lifetime. Fortunately, a theory based on fracture mechanics has been developed enabling lifetime predictions to be made for brittle materials susceptible to delayed failure. Knowledge of the factors governing the rate of subcritical flaw growth in a given environment enables the development of

  8. Development of an optical fiber interferometer for detection of surface flaws in aluminum

    NASA Technical Reports Server (NTRS)

    Gilbert, John A.

    1991-01-01

    The main objective was to demonstrate the potential of using an optical fiber interferometer (OFI) to detect surface flaws in aluminum samples. Standard ultrasonic excitation was used to generate Rayleigh surface waves. After the waves interacted with a defect, the modified responses were detected using the OFI and the results were analyzed for time-of-flight and frequency content to predict the size and location of the flaws.

  9. Detection and Characterization of Flaws in Sprayed on Foam Insulation with Pulsed Terahertz Frequency Electromagnetic Waves

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Madaras, Eric I.

    2005-01-01

    The detection and repair of flaws such as voids and delaminations in the sprayed on foam insulation of the external tank reduces the probability of foam debris during shuttle ascent. The low density of sprayed on foam insulation along with it other physical properties makes detection of flaws difficult with conventional techniques. An emerging technology that has application for quantitative evaluation of flaws in the foam is pulsed electromagnetic waves at terahertz frequencies. The short wavelengths of these terahertz pulses make them ideal for imaging flaws in the foam. This paper examines the application of terahertz pulses for flaw detection in foam characteristic of the foam insulation of the external tank. Of particular interest is the detection of voids and delaminations, encapsulated in the foam or at the interface between the foam and a metal backing. The technique is shown to be capable of imaging small voids and delaminations through as much as 20 cm of foam. Methods for reducing the temporal responses of the terahertz pulses to improve flaw detection and yield quantitative characterizations of the size and location of the flaws are discussed.

  10. On flaw tolerance of nacre: a theoretical study.

    PubMed

    Shao, Yue; Zhao, Hong-Ping; Feng, Xi-Qiao

    2014-03-01

    As a natural composite, nacre has an elegant staggered 'brick-and-mortar' microstructure consisting of mineral platelets glued by organic macromolecules, which endows the material with superior mechanical properties to achieve its biological functions. In this paper, a microstructure-based crack-bridging model is employed to investigate how the strength of nacre is affected by pre-existing structural defects. Our analysis demonstrates that owing to its special microstructure and the toughening effect of platelets, nacre has a superior flaw-tolerance feature. The maximal crack size that does not evidently reduce the tensile strength of nacre is up to tens of micrometres, about three orders higher than that of pure aragonite. Through dimensional analysis, a non-dimensional parameter is proposed to quantify the flaw-tolerance ability of nacreous materials in a wide range of structural parameters. This study provides us some inspirations for optimal design of advanced biomimetic composites. PMID:24402917

  11. NON-DESTRUCTIVE METHOD AND MEANS FOR FLAW DETECTION

    DOEpatents

    Hochschild, R.

    1959-03-10

    BS>An improved method is presented for the nondestructive detection of flaws in olectrictilly conductivc articles using magnetic field. According to thc method a homogoneous mignetic field is established in the test article;it right angle" to the artyicle. A probe is aligned with its axis transverse to the translates so hat th4 probe scans the surface of the test article while the axis of the robe is transverse to the direction of translation of the article. In this manner any output current obtained in thc probe is an indication of the size and location of a flaw in the article under test, with a miiiimum of signal pick- up in the probe from the established magnetic field.

  12. NON-DESTRUCTIVE FLAW DETECTION APPARATUS

    DOEpatents

    Stateman, M.J.; Holloway, H.R.

    1957-12-17

    An apparatus is described for the non-destructive detection of flaws in electrical conducting articles. The particular feature of the detection apparatus is that a flaw in the front or back of the test article will not be masked by signals caused by the passage of the end and front of the article through the detection apparatus. The present invention alleviates the above problem by mounting detection coils on directly opposite sides of the test passageway so that the axes of the pickup coils are perpendicular to the axis of an energizing coil through which the article is passed. A flaw in the article will cause a change in the voltage induced in one pickup coil, but passage of the end or front of the article will not produce unequal signals. The signals are compared in appropriate electrical circuitry to actuate a recorder only when unequal signals are present, indicating the presence of a flaw.

  13. ULTRASONIC FLAW DETECTION METHOD AND MEANS

    DOEpatents

    Worlton, D.C.

    1961-08-15

    A method of detecting subsurface flaws in an object using ultrasonic waves is described. An ultnasonic wave of predetermined velocity and frequency is transmitted to engage the surface of the object at a predetermined angle of inci dence thereto. The incident angle of the wave to the surface is determined with respect to phase velocity, incident wave velocity, incident wave frequency, and the estimated depth of the flaw so that Lamb waves of a particular type and mode are induced only in the portion of the object between the flaw and the surface. These Lamb waves are then detected as they leave the object at an angle of exit equal to the angle of incidence. No waves wlll be generated in the object and hence received if no flaw exists beneath the surface. (AEC)

  14. Flaw tolerance promoted by dissipative deformation mechanisms between material building blocks

    NASA Astrophysics Data System (ADS)

    Verho, Tuukka; Buehler, Markus J.

    2014-09-01

    Novel high-performance composite materials often draw inspiration from natural materials such as bone or mollusc shells. A prime feature of such composites is that they are, like their natural counterparts, quasibrittle. They are tolerant to material flaws up to a certain characteristic flaw-tolerant size scale, exhibiting high strength and toughness, but start to behave in a brittle manner when sufficiently large flaws are present. Here, we establish that better flaw tolerance can be achieved by maximizing fracture toughness relative to the maximum elastic energy available in the material, and we demonstrate this concept with simple two-dimensional coarse-grained simulations where the transition from brittle to quasibrittle behaviour is examined.

  15. Simulating the X-Ray Image Contrast to Set-Up Techniques with Desired Flaw Detectability

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2015-01-01

    The paper provides simulation data of previous work by the author in developing a model for estimating detectability of crack-like flaws in radiography. The methodology is being developed to help in implementation of NASA Special x-ray radiography qualification, but is generically applicable to radiography. The paper describes a method for characterizing X-ray detector resolution for crack detection. Applicability of ASTM E 2737 resolution requirements to the model are also discussed. The paper describes a model for simulating the detector resolution. A computer calculator application, discussed here, also performs predicted contrast and signal-to-noise ratio calculations. Results of various simulation runs in calculating x-ray flaw size parameter and image contrast for varying input parameters such as crack depth, crack width, part thickness, x-ray angle, part-to-detector distance, part-to-source distance, source sizes, and detector sensitivity and resolution are given as 3D surfaces. These results demonstrate effect of the input parameters on the flaw size parameter and the simulated image contrast of the crack. These simulations demonstrate utility of the flaw size parameter model in setting up x-ray techniques that provide desired flaw detectability in radiography. The method is applicable to film radiography, computed radiography, and digital radiography.

  16. Midland reactor pressure vessel flaw distribution

    SciTech Connect

    Foulds, J.R.; Kennedy, E.L.; Rosinski, S.T.

    1993-12-01

    The results of laboratory nondestructive examination (NDE), and destructive cross-sectioning of selected weldment sections of the Midland reactor pressure vessel were analyzed per a previously developed methodology in order to develop a flaw distribution. The flaw distributions developed from the NDE results obtained by two different ultrasonic test (UT) inspections (Electric Power Research Institute NDE Center and Pacific Northwest Laboratories) were not statistically significantly different. However, the distribution developed from the NDE Center`s (destructive) cross-sectioning-based data was found to be significantly different than those obtained through the UT inspections. A fracture mechanics-based comparison of the flaw distributions showed that the cross-sectioning-based data, conservatively interpreted (all defects considered as flaws), gave a significantly lower vessel failure probability when compared with the failure probability values obtained using the UT-based distributions. Given that the cross-sectioning data were reportedly biased toward larger, more significant-appearing (by UT) indications, it is concluded that the nondestructive examinations produced definitively conservative results. In addition to the Midland vessel inspection-related analyses, a set of twenty-seven numerical simulations, designed to provide a preliminary quantitative assessment of the accuracy of the flaw distribution method used here, were conducted. The calculations showed that, in more than half the cases, the analysis produced reasonably accurate predictions.

  17. Ultrasonic Phased Array Evaluations Of Implanted And In-Situ Grown Flaws In Cast Austenitic Stainless Steel Pressurizer Surge Line Piping

    SciTech Connect

    Crawford, Susan L.; Cinson, Anthony D.; Moran, Traci L.; Prowant, Matthew S.; Diaz, Aaron A.; Anderson, Michael T.

    2011-07-31

    A set of circumferentially oriented thermal fatigue cracks (TFCs) were implanted into three cast austenitic stainless steel (CASS) pressurizer (PZR) surge-line specimen welds (pipe-to-elbow configuration) that were salvaged from a U.S. commercial nuclear power plant that had not been operated. Thus, these welds were fabricated using vintage CASS materials that were formed in the 1970s. Additionally, in-situ grown TFCs were placed in the adjacent CASS base material of one of these specimens. Ultrasonic phased-array responses from both types of flaws (implanted and in-situ grown) were analyzed for detection and characterization based on sizing and signal-to-noise determination. Multiple probes were employed covering the 0.8 to 2.0 MHz frequency range. To further validate the Pacific Northwest National Laboratory (PNNL) findings, an independent in-service inspection (ISI) supplier evaluated the flaws with their American Society of Mechanical Engineers (ASME) Code, Section XI, Appendix VIII-qualified procedure. The results obtained by PNNL personnel compared favorably to the ISI supplier results. All examined flaws were detected and sized within the ASME Code-allowable limits.

  18. Steam generator tube integrity flaw acceptance criteria

    SciTech Connect

    Cochet, B.

    1997-02-01

    The author discusses the establishment of a flaw acceptance criteria with respect to flaws in steam generator tubing. The problem is complicated because different countries take different approaches to the problem. The objectives in general are grouped in three broad areas: to avoid the unscheduled shutdown of the reactor during normal operation; to avoid tube bursts; to avoid excessive leak rates in the event of an accidental overpressure event. For each degradation mechanism in the tubes it is necessary to know answers to an array of questions, including: how well does NDT testing perform against this problem; how rapidly does such degradation develop; how well is this degradation mechanism understood. Based on the above information it is then possible to come up with a policy to look at flaw acceptance. Part of this criteria is a schedule for the frequency of in-service inspection and also a policy for when to plug flawed tubes. The author goes into a broad discussion of each of these points in his paper.

  19. Prevention of design flaws in multicomputer systems

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Multicomputer configurations and redundancy management techniques used in various airborne systems were investigated to determine methods to prevent and/or treat generic design flaws. The findings are intended for use in the design of a computer system for use in the space shuttle orbiter.

  20. NCLB Transfer Policy Seen as Flawed

    ERIC Educational Resources Information Center

    Hendrie, Caroline

    2005-01-01

    This article examines what some people see as flaws in the transfer policy provision of the No Child Left Behind law. Advocates of the policy are calling for providing schools with incentives to accept transfers and for giving parents more time, information, and options, among other changes. States need to hold districts' feet to the fire, those…

  1. Window flaw detection by backscatter lighting

    NASA Technical Reports Server (NTRS)

    Crockett, L. K.; Minton, F. R.

    1978-01-01

    Portable fiber-optic probe detects tiny flaws in transparent materials. Probe transmits light through surface to illuminate interior of material by backscattering off its edges. Light-sensitive contact paper records scratch pattern. Technique can be used for rapid visual checks. Flexible fiber optics are safely used in explosive or flammable areas; they present no hazard of breakage or contamination in controlled environments.

  2. Method for fabricating prescribed flaws in the interior of metals

    DOEpatents

    Hsu, David K.; Thompson, Donald O.

    1989-03-07

    The method for fabricating a metal body having a flaw of predetermined size and shape located therein comprises placing half of the metal powder required to make the metal body in the die of a press and pressing it to create a flat upper surface thereon. A piece of copper foil is cut to the size and shape of the desired interior crack and placed on the upper surface of the powder and centered in position. The remaining powder is then placed in the die to cover the copper foil. The powder is first cold pressed and removed from the press. The powder metal piece is then sintered in a furnace at a temperature above the melting point of the copper and below the melting point of the metal. It is then removed from the furnace, cooled to room temperature, and placed back in the die and pressed further. This procedure results in an interior flaw or crack. Modified forms of the method involve using a press-sinter-press-sinter cycle with the first sinter being below the melting point of the copper and the second sinter being above the melting point of the copper and below the melting point of the metal.

  3. Electronic flaw simulator for eddy current probe calibration

    NASA Technical Reports Server (NTRS)

    Almasy, L. J.; Cowfer, C. D.

    1970-01-01

    Electronic flaw simulator cycled into the eddy current system eliminates errors in probe calibration. A discrimination level reference established in the probe permits recognition of those flaws in materials with an equivalent volume equal to or greater than the reference.

  4. Procedure for flaw detection in cast stainless steel

    DOEpatents

    Kupperman, David S.

    1988-01-01

    A method of ultrasonic flaw detection in cast stainless steel components incorporating the steps of determining the nature of the microstructure of the cast stainless steel at the site of the flaw detection measurements by ultrasonic elements independent of the component thickness at the site; choosing from a plurality of flaw detection techniques, one such technique appropriate to the nature of the microstructure as determined and detecting flaws by use of the chosen technique.

  5. Apparatus and method for detecting flaws in conductive material

    DOEpatents

    Hockey, Ronald L.; Riechers, Douglas M.

    1999-01-01

    The present invention is an improved sensing unit for detecting flaws in conductive material wherein the sensing coil is positioned away from a datum of either the datum point, the datum orientation, or a combination thereof. Position of the sensing coil away from a datum increases sensitivity for detecting flaws having a characteristic volume less than about 1 mm.sup.3, and further permits detection of subsurface flaws. Use of multiple sensing coils permits quantification of flaw area or volume.

  6. Feasibility for development of a nuclear reactor pressure vessel flaw distribution: Sensitivity analyses and NDE (nondestructive evaluation) capability

    SciTech Connect

    Rosinski, S.T. ); Kennedy, E.L.; Foulds, J.R. )

    1990-01-01

    Pressurized water reactor pressure vessels operate under US Nuclear Regulatory Commission (NRC) rules and regulatory guides that are intended to maintain a low probability of vessel failure. The NRC has also addressed neutron embrittlement of pressurized water reactor pressure vessels by imposing regulations on plant operation. Plants failing to meet the operating criteria specified by these rules and regulations are required, among other things, to analytically demonstrate fitness for service in order to continue safe operation. The initial flaw size or distribution of initial vessel flaws is a key input to the required vessel integrity analyses. A fracture mechanics sensitivity study was performed to quantify the effect of the assumed flaw distribution on the predicted vessel performance under a specified pressurized thermal shock transient and to determine the critical crack size. Results of the analysis indicate that vessel performance in terms of the estimated probability of failure is very sensitive to the assumed flaw distribution. 20 refs., 3 figs., 2 tabs.

  7. Evaluation of flawed piping under dynamic loading

    SciTech Connect

    Nickell, R.E.; Quinones, D.F.; Gilman, J.D.

    1992-10-01

    This report describes analytical and interpretative research on results of large-scale dynamic tests of flawed pipe which were conducted for the International Piping Integrity Research Group (IPIRG). Here, the adequacy of dynamic analysis methods is examined, as well as margins against failure associated with flaw evaluation criteria. Experimental and analytical results are related to requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Codes. Code limits of operability bound all test results. Guidance is offered on selection of ``Z-factors`` for austenitic materials to retain code safety margins. In the IPIRG tests, efforts to produce a nearly instantaneous full severance pipe break were unsuccessful, indicating that this hypothetical basis for plant accident evaluations is conservative.

  8. Evaluation of flawed piping under dynamic loading

    SciTech Connect

    Nickell, R.E. ); Quinones, D.F. and Associates, Inc., Berkeley, CA ); Gilman, J.D. )

    1992-10-01

    This report describes analytical and interpretative research on results of large-scale dynamic tests of flawed pipe which were conducted for the International Piping Integrity Research Group (IPIRG). Here, the adequacy of dynamic analysis methods is examined, as well as margins against failure associated with flaw evaluation criteria. Experimental and analytical results are related to requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Codes. Code limits of operability bound all test results. Guidance is offered on selection of Z-factors'' for austenitic materials to retain code safety margins. In the IPIRG tests, efforts to produce a nearly instantaneous full severance pipe break were unsuccessful, indicating that this hypothetical basis for plant accident evaluations is conservative.

  9. Development of flaw acceptance criteria for aging management of spent nuclear fuel multiple-purpose canisters

    SciTech Connect

    Lam, P.; Sindelar, R.

    2015-03-09

    A typical multipurpose canister (MPC) is made of austenitic stainless steel and is loaded with spent nuclear fuel assemblies. The canister may be subject to service-induced degradation when it is exposed to aggressive atmospheric environments during a possibly long-term storage period if the permanent repository is yet to be identified and readied. Because heat treatment for stress relief is not required for the construction of an MPC, stress corrosion cracking may be initiated on the canister surface in the welds or in the heat affected zone. An acceptance criteria methodology is being developed for flaw disposition should the crack-like defects be detected by periodic In-service Inspection. The first-order instability flaw sizes has been determined with bounding flaw configurations, that is, through-wall axial or circumferential cracks, and part-through-wall long axial flaw or 360° circumferential crack. The procedure recommended by the American Petroleum Institute (API) 579 Fitness-for-Service code (Second Edition) is used to estimate the instability crack length or depth by implementing the failure assessment diagram (FAD) methodology. The welding residual stresses are mostly unknown and are therefore estimated with the API 579 procedure. It is demonstrated in this paper that the residual stress has significant impact on the instability length or depth of the crack. The findings will limit the applicability of the flaw tolerance obtained from limit load approach where residual stress is ignored and only ligament yielding is considered.

  10. Predicting Flaw-Induced Resonance Spectrum Shift with Theoretical Perturbation Analysis

    SciTech Connect

    Lai, Canhai; Sun, Xin

    2013-10-28

    Resonance inspection is an emerging non-destructive evaluation (NDE) technique which uses the resonance spectra differences between the good part population and the flawed parts to identify anomalous parts. It was previously established that finite-element (FE)-based modal analysis can be used to predict the resonance spectrum for an engineering scale part with relatively good accuracy. However, FE-based simulations can be time consuming in examining the spectrum shifts induced by all possible structural flaws. This paper aims at developing a computationally efficient perturbation technique to quantify the frequency shifts induced by small structural flaws, based on the FE simulated resonance spectrum for the perfect part. A generic automotive connecting rod is used as the example part for our study. The results demonstrate that the linear perturbation theory provides a very promising way in predicting frequency changes induced by small structural flaws. As the flaw size increases, the discrepancy between the perturbation analysis and the actual FE simulation results increases due to nonlinearity, yet the perturbation analysis is still able to predict the right trend in frequency shift.

  11. Predicting flaw-induced resonance spectrum shift with theoretical perturbation analysis

    NASA Astrophysics Data System (ADS)

    Lai, C.; Sun, X.

    2013-10-01

    Resonance inspection is an emerging non-destructive evaluation (NDE) technique used by the automotive casting industry which uses the resonance spectra differences between the good part population and the flawed parts to identify anomalous parts. It was previously established that finite-element (FE)-based modal analysis can be used to predict the resonance spectrum for an engineering scale part with relatively good accuracy. However, FE-based simulations can be time consuming in examining the spectrum shifts induced by all possible structural flaws. This paper aims at developing a computationally efficient perturbation technique to quantify the frequency shifts induced by small structural flaws, based on the FE simulated resonance spectrum for the perfect part. A generic automotive connecting rod is used as the example part for our study. The results demonstrate that the linear perturbation theory provides a very promising way in predicting frequency changes induced by small structural flaws. As the flaw size increases, the discrepancy between the perturbation analysis and the actual FE simulation results increases due to nonlinearity, yet the perturbation analysis is still able to predict the right trend in frequency shift.

  12. Application of elastic and elastic-plastic fracture mechanics methods to surface flaws

    NASA Astrophysics Data System (ADS)

    McCabe, Donald E.; Ernst, Hugo A.; Newman, James C., Jr.

    Fuel tanks that are a part of the External Tank assembly for the Space Shuttle are made of relatively thin 2219-T87 aluminum plate. These tanks contain about 917 m of fusion weld seam, all of which is nondestructively inspected for flaws and all those found are repaired. The tanks are subsequently proof-tested to a pressure that is sufficiently severe to cause weld metal yielding in a few local regions of the weld seam. The work undertaken in the present project was to develop a capability to predict flaw growth from undetected surface flaws that are assumed to be located in the highly stressed regions. The technical challenge was to develop R-curve prediction capability for surface cracks in specimens that contain the flaws of unusual sizes and shapes deemed to be of interest. The test techniques developed and the elastic-plastic analysis concepts adopted are presented. The flaws of interest were quite small surface cracks that were narrow-deep ellipses that served to exacerbate the technical difficulties involved.

  13. Development of flaw acceptance criteria for aging management of spent nuclear fuel multi-purpose canisters

    SciTech Connect

    Lam, Poh -Sang; Sindelar, Robert L.

    2015-03-09

    A typical multipurpose canister (MPC) is made of austenitic stainless steel and is loaded with spent nuclear fuel assemblies. The canister may be subject to service-induced degradation when it is exposed to aggressive atmospheric environments during a possibly long-term storage period if the permanent repository is yet to be identified and readied. Because heat treatment for stress relief is not required for the construction of an MPC, stress corrosion cracking may be initiated on the canister surface in the welds or in the heat affected zone. An acceptance criteria methodology is being developed for flaw disposition should the crack-like defects be detected by periodic in-service Inspection. The first-order instability flaw sizes has been determined with bounding flaw configurations, that is, through-wall axial or circumferential cracks, and part-through-wall long axial flaw or 360° circumferential crack. The procedure recommended by the American Petroleum Institute (API) 579 Fitness-for-Service code (Second Edition) is used to estimate the instability crack length or depth by implementing the failure assessment diagram (FAD) methodology. The welding residual stresses are mostly unknown and are therefore estimated with the API 579 procedure. It is demonstrated in this paper that the residual stress has significant impact on the instability length or depth of the crack. The findings will limit the applicability of the flaw tolerance obtained from limit load approach where residual stress is ignored and only ligament yielding is considered.

  14. Magnetoresistive Flux Focusing Eddy Current Flaw Detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Namkung, Min (Inventor); Simpson, John W. (Inventor)

    2005-01-01

    A giant magnetoresistive flux focusing eddy current device effectively detects deep flaws in thick multilayer conductive materials. The probe uses an excitation coil to induce eddy currents in conducting material perpendicularly oriented to the coil s longitudinal axis. A giant magnetoresistive (GMR) sensor, surrounded by the excitation coil, is used to detect generated fields. Between the excitation coil and GMR sensor is a highly permeable flux focusing lens which magnetically separates the GMR sensor and excitation coil and produces high flux density at the outer edge of the GMR sensor. The use of feedback inside the flux focusing lens enables complete cancellation of the leakage fields at the GMR sensor location and biasing of the GMR sensor to a location of high magnetic field sensitivity. In an alternate embodiment, a permanent magnet is positioned adjacent to the GMR sensor to accomplish the biasing. Experimental results have demonstrated identification of flaws up to 1 cm deep in aluminum alloy structures. To detect deep flaws about circular fasteners or inhomogeneities in thick multi-layer conductive materials, the device is mounted in a hand-held rotating probe assembly that is connected to a computer for system control, data acquisition, processing and storage.

  15. Magnetoresistive flux focusing eddy current flaw detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Namkung, Min (Inventor); Simpson, John W. (Inventor)

    2005-01-01

    A giant magnetoresistive flux focusing eddy current device effectively detects deep flaws in thick multilayer conductive materials. The probe uses an excitation coil to induce eddy currents in conducting material perpendicularly oriented to the coil's longitudinal axis. A giant magnetoresistive (GMR) sensor, surrounded by the excitation coil, is used to detect generated fields. Between the excitation coil and GMR sensor is a highly permeable flux focusing lens which magnetically separates the GMR sensor and excitation coil and produces high flux density at the outer edge of the GMR sensor. The use of feedback inside the flux focusing lens enables complete cancellation of the leakage fields at the GMR sensor location and biasing of the GMR sensor to a location of high magnetic field sensitivity. In an alternate embodiment, a permanent magnet is positioned adjacent to the GMR sensor to accomplish the biasing. Experimental results have demonstrated identification of flaws up to 1 cm deep in aluminum alloy structures. To detect deep flaws about circular fasteners or inhomogeneities in thick multilayer conductive materials, the device is mounted in a hand-held rotating probe assembly that is connected to a computer for system control, data acquisition, processing and storage.

  16. Characterization of flaws in a tube bundle mock-up for reliability studies

    SciTech Connect

    Kupperman, D.S.; Bakhtiari, S.

    1997-02-01

    As part of an assessment of in-service inspection of steam generator tubes, the authors will assemble a steam generator mock-up for round robin studies and use as a test bed in evaluating emerging technologies. Progress is reported on the characterization of flaws that will be part of the mock-up. Eddy current and ultrasonic techniques are being evaluated as a means to characterize the flaws in the mock-up tubes before final assembly. Twenty Inconel 600 tubes with laboratory-grown cracks, typical of those to be used in the mock-up, were provided by Pacific Northwest National Laboratory for laboratory testing. After the tubes were inspected with eddy current and ultrasonic techniques, they were destructively analyzed to establish the actual depths, lengths, and profiles of the cracks. The analysis of the results will allow the best techniques to be used for characterizing the flaws in the mock-up tubes.

  17. Effect of Fe- and Si-induced flaws on fracture of Si{sub 3}N{sub 4}

    SciTech Connect

    Singh, J.P.

    1997-10-01

    Fracture studies were performed to detect and assess the effect of flaws on the fracture behavior of hot-pressed Si{sub 3}N{sub 4} with Fe or Si inclusions. The addition of 5 and 0.5 wt.% Fe inclusions of 88--250 {micro}m size reduced the strength of Si{sub 3}N{sub 4} specimens by {approx} 40 and 15%, respectively. Similarly, addition of 1 and 0.5 wt.% Si inclusions of < 149 {micro}m size reduced the strength of Si{sub 3}N{sub 4} specimens by {approx} 50 and 39%, respectively. Fractography indicated that failure occurred primarily from internal flaws which included Fe- and Si-rich inclusions and/or regions of Si{sub 3}N{sub 4} matrix that were degraded as a result of reaction between Si{sub 3}N{sub 4} and molten Fe or Si. For inclusion-induced internal flaws, the critical flaw sizes calculated by fracture mechanics were always larger than the fractographically measured flaw sizes. This observation suggested local degradation in fracture toughness of the Si{sub 3}N{sub 4} matrix. A ratio, K, of {approx} 3.5--4.2 appeared to exist between the calculated and measured values of the critical internal flaw sizes of specimens that contained Fe inclusions. A similar ratio of 1.7--3.1 was observed for specimens that contained Si inclusions. The ratio K has important implications for strength predictions that are based on observed flaw size.

  18. Non-contact rail flaw detection system: first field test

    NASA Astrophysics Data System (ADS)

    Rizzo, Piervincenzo; Coccia, Stefano; Lanza di Scalea, Francesco; Bartoli, Ivan; Fateh, Mahmood

    2007-04-01

    Researchers at UCSD, with the initial support of NSF and the current support of the Federal Railroad Administration (FRA), have been working on a flaw detection prototype for rails that uses non-contact ultrasonic probing and robust data processing algorithms to provide high speed and high reliability defect detection in these structures. Besides the obvious advantages of non-contact probing, the prototype uses ultrasonic guided waves able to detect and quantify transverse cracks in the rail head, notoriously the most dangerous of all rail track defects. This paper will report on the first field test which was conducted in Gettysburg, PA in March 2006 with the technical support of ENSCO, Inc. Good results were obtained for the detection of both surface-breaking and internal cracks ranging in size from 2% cross-sectional head area (H.A.) reduction to 80% H.A. reduction.

  19. Growth and stability of interacting surface flaws of arbitrary shape

    NASA Technical Reports Server (NTRS)

    Murakami, Y.; Nemat-Nasser, S.

    1983-01-01

    Growth regimes of interacting surface flaws of arbitrary shape are analyzed with the aid of the body force method, and the stability of the process is assessed on the basis of the variation of the load during the growth. It is shown that irregularly shaped flaws are often associated with very high stress intensity factors locally, which tend to change as the flaws grow into more regular shapes. Several examples of various flaw shapes are worked out for illustration, and it is shown that a simple formula seems to provide an accurate estimate of the maximum stress intensity factor for surface flaws of various shapes, which are not very slender. The formula involves the overall maximum tension, as well as the area of the projection of the flaw on the plane normal to the maximum tension.

  20. High-temperature flaw assessment procedure

    SciTech Connect

    Ruggles, M.B. ); Takahashi, Y. ); Ainsworth, R.A. )

    1991-08-01

    Described is the background work performed jointly by the Electric Power Research Institute in the United States, the Central Research Institute of Electric Power Industry in Japan and Nuclear Electric plc in the United Kingdom with the purpose of developing a high-temperature flaw assessment procedure for reactor components. Existing creep-fatigue crack-growth models are reviewed, and the most promising methods are identified. Sources of material data are outlined, and results of the fundamental deformation and crack-growth tests are discussed. Results of subcritical crack-growth exploratory tests, creep-fatigue crack-growth tests under repeated thermal transient conditions, and exploratory failure tests are presented and contrasted with the analytical modeling. Crack-growth assessment methods are presented and applied to a typical liquid-metal reactor component. The research activities presented herein served as a foundation for the Flaw Assessment Guide for High-Temperature Reactor Components Subjected to Creep-Fatigue Loading published separately. 30 refs., 108 figs., 13 tabs.

  1. Preclinical animal anxiety research - flaws and prejudices.

    PubMed

    Ennaceur, Abdelkader; Chazot, Paul L

    2016-04-01

    The current tests of anxiety in mice and rats used in preclinical research include the elevated plus-maze (EPM) or zero-maze (EZM), the light/dark box (LDB), and the open-field (OF). They are currently very popular, and despite their poor achievements, they continue to exert considerable constraints on the development of novel approaches. Hence, a novel anxiety test needs to be compared with these traditional tests, and assessed against various factors that were identified as a source of their inconsistent and contradictory results. These constraints are very costly, and they are in most cases useless as they originate from flawed methodologies. In the present report, we argue that the EPM or EZM, LDB, and OF do not provide unequivocal measures of anxiety; that there is no evidence of motivation conflict involved in these tests. They can be considered at best, tests of natural preference for unlit and/or enclosed spaces. We also argued that pharmacological validation of a behavioral test is an inappropriate approach; it stems from the confusion of animal models of human behavior with animal models of pathophysiology. A behavioral test is developed to detect not to produce symptoms, and a drug is used to validate an identified physiological target. In order to overcome the major methodological flaws in animal anxiety studies, we proposed an open space anxiety test, a 3D maze, which is described here with highlights of its various advantages over to the traditional tests. PMID:27069634

  2. Signal/Image Processing of Acoustic Flaw Signatures for Detection and Localization

    SciTech Connect

    Candy, J V; Meyer, A W

    2001-06-01

    The timely, nondestructive evaluation (NDE) of critical optics in high energy, pulsed laser experiments is a crucial analysis that must be performed for the experiment to be successful. Failure to detect flaws of critical sizes in vacuum-loaded optical windows can result in a catastrophic failure jeopardizing the safety of both personnel and costly equipment. We discuss the development of signal/image processing techniques to both detect critical flaws and locate their position on the window. The data measured from two Orthogonal arrays of narrow beamwidth ultrasonic transducers are preprocessed using a model-based scheme based on the Green's function of the medium providing individual channel signatures. These signatures are then transformed to the two-dimensional image space using a power-based estimator. A 2D-replicant is then constructed based on the underlying physics of the material along with the geometry of the window. Correlating the replicant with the enhanced power image leads to the optimal 2D-matched filter solution detecting and localizing the flaw. Controlled experimental results on machined flaws are discussed.

  3. Origin of flaw-tolerance in nacre

    PubMed Central

    Huang, Zaiwang; Li, Xiaodong

    2013-01-01

    Over the past decades, our understanding of nacre's toughening origin has long stayed at the level of crack deflection along the biopolymer interface between aragonite platelets. It has been widely thought that the ceramic aragonite platelets in nacre invariably remain shielded from the propagating crack. Here we report an unexpected experimental observation that the propagating crack, surprisingly, invades the aragonite platelet following a zigzag crack propagation trajectory. The toughening origin of previously-thought brittle aragonite platelet is ascribed to its unique nanoparticle-architecture, which tunes crack propagation inside the aragonite platelet in an intergranular manner. For comparison, we also investigated the crack behavior in geologic aragonite mineral (pure monocrystal) and found that the crack propagates in a cleavage fashion, in sharp contrast with the intergranular cracking in the aragonite platelet of nacre. These two fundamentally different cracking mechanisms uncover a new toughening strategy in nacre's hierarchical flaw-tolerance design. PMID:23603788

  4. Origin of flaw-tolerance in nacre

    NASA Astrophysics Data System (ADS)

    Huang, Zaiwang; Li, Xiaodong

    2013-04-01

    Over the past decades, our understanding of nacre's toughening origin has long stayed at the level of crack deflection along the biopolymer interface between aragonite platelets. It has been widely thought that the ceramic aragonite platelets in nacre invariably remain shielded from the propagating crack. Here we report an unexpected experimental observation that the propagating crack, surprisingly, invades the aragonite platelet following a zigzag crack propagation trajectory. The toughening origin of previously-thought brittle aragonite platelet is ascribed to its unique nanoparticle-architecture, which tunes crack propagation inside the aragonite platelet in an intergranular manner. For comparison, we also investigated the crack behavior in geologic aragonite mineral (pure monocrystal) and found that the crack propagates in a cleavage fashion, in sharp contrast with the intergranular cracking in the aragonite platelet of nacre. These two fundamentally different cracking mechanisms uncover a new toughening strategy in nacre's hierarchical flaw-tolerance design.

  5. Application of acoustic emission to flaw detection in engineering materials

    NASA Technical Reports Server (NTRS)

    Moslehy, F. A.

    1990-01-01

    Monitoring of structures under operating loads to provide an early warning of possible failure to locate flaws in test specimens subjected to uniaxial tensile loading is presented. Test specimens used are mild steel prismatic bars with small holes at different locations. When the test specimen is loaded, acoustic emission data are automatically collected by two acoustic transducers located at opposite sides of the hole and processed by an acoustic emission analyzer. The processed information yields the difference in arrival times at the transducers, which uniquely determines the flaw location. By using this technique, flaws were located to within 8 percent of their true location. The use of acoustic emission in linear location to locate a flaw in a material is demonstrated. It is concluded that this one-dimensional application could be extended to the general flaw location problem through triangulation.

  6. An interim report on shallow-flaw fracture technology development

    SciTech Connect

    Pennell, W.E.; Bass, B.R.; Bryson, J.W.; McAfee, W.J.

    1995-06-01

    Shallow-flaw fracture technology is being developed for application to the safety assessment of radiation-embrittled nuclear reactor pressure vessels (RPVS) containing flaws. Fracture mechanics tests on RPV steel, coupled with detailed elastic-plastic finite-element analyses of the crack-tip stress fields, have shown that (1) constraint relaxation at the crack tip of shallow surface flaws results in increased data scatter but no increase in the lower-bound fracture toughness, (2) the nil ductility temperature (NDT) performs better than the reference temperature for nil ductility transition (RT{sub NDT}) as a normalizing parameter for shallow-flaw fracture toughness data, (3) biaxial loading can reduce the shallow-flaw fracture toughness, (4) stress-based dual-parameter fracture toughness correlations cannot predict the effect of biaxial loading on shallow-flaw fracture toughness because in-plane stresses at the crack tip are not influenced by biaxial loading, and (5) a strain-based dual-parameter fracture toughness correlation can predict the effect of biaxial loading on shallow-flaw fracture toughness.

  7. The behavior of shallow flaws in reactor pressure vessels

    SciTech Connect

    Rolfe, S.T. )

    1991-11-01

    Both analytical and experimental studies have shown that the effect of crack length, a, on the elastic-plastic toughness of structural steels is significant. The objective of this report is to recommend those research investigations that are necessary to understand the phenomenon of shallow behavior as it affects fracture toughness so that the results can be used properly in the structural margin assessment of reactor pressure vessels (RPVs) with flaws. Preliminary test results of A 533 B steel show an elevated crack-tip-opening displacement (CTOD) toughness similar to that observed for structural steels tested at the University of Kansas. Thus, the inherent resistance to fracture initiation of A 533 B steel with shallow flaws appears to be higher than that used in the current American Society of Mechanical Engineers (ASME) design curves based on testing fracture mechanics specimens with deep flaws. If this higher toughness of laboratory specimens with shallow flaws can be transferred to a higher resistance to failure in RPV design or analysis, then the actual margin of safety in nuclear vessels with shallow flaws would be greater than is currently assumed on the basis of deep-flaw test results. This elevation in toughness and greater resistance to fracture would be a very desirable situation, particularly for the pressurized-thermal shock (PTS) analysis in which shallow flaws are assumed to exist. Before any advantage can be taken of this possible increase in initiation toughness, numerous factors must be analyzed to ensure the transferability of the data. This report reviews those factors and makes recommendations of studies that are needed to assess the transferability of shallow-flaw toughness test results to the structural margin assessment of RPV with shallow flaws. 14 refs., 8 figs.

  8. Flaw length distribution measurement in brittle materials

    NASA Astrophysics Data System (ADS)

    Rabinovitch, A.; Zlotnikov, R.; Bahat, D.

    2000-06-01

    A technique was developed in an experiment of fractured soda-lime glass which yielded a wide mist zone. This technique enabled us to measure the lengths of a large number (≈ 12 000) of secondary cracks (SC) in this zone. Statistical analysis of these lengths across the mist as a function of distance from fracture origin revealed some unexpected results. (a) The total number of SC remains constant for ≈ 40% of the width of the mist zone and subsequently decreases monotonically down to ≈ 50% of the initial number towards the end of this zone. (b) The length distribution of SC can be interpreted as constituting of two populations: (1) A nucleated SC population which remains unchanged across the whole mist. This distribution consists of two subpopulations: (i) half Gaussian (around 84%), and (ii) decaying exponential (around 16%). (2) A rather small portion of the nucleated population of SC (≈ 9% throughout) which grow monotonically by a factor of up to 40 with distance across the mist. (c) This factor agrees well with our theoretical calculation of the growth mode, and yields a reasonable estimate of the radius of the initial critical flaw (1.85 mm).

  9. Flaw detection and segmentation in textile inspection

    NASA Astrophysics Data System (ADS)

    Millán, María S.; Ralló, Miquel; Escofet, Jaume

    2008-04-01

    We present a new method to automatically segment local defects in a woven fabric that does not require any additional defect-free reference for comparison. Firstly, the structural features of the repetition pattern of the minimal weave repeat are extracted from the Fourier spectrum of the sample under inspection. The corresponding peaks are automatically identified and removed from the fabric frequency spectrum. Secondly, we define a set of multi-scale oriented bandpass filters, adapted to the specific structure of the sample, that operate in the Fourier domain. The filter design is the key part of the method. Using the set of filters, local defects can be extracted. Thirdly, the filtered images obtained at different scales are inverse Fourier transformed, binarized and merged to obtain an output image where flaws are segmented from the fabric background. The method can be applied to fabrics of uniform color as well as to fabrics woven with threads of different colors. It is Euclidean motion invariant and texture adaptive and it is useful for automatic inspection both online and off-line. The whole process is fully automatic and can be implemented either optical or electronically. A variety of experimental results are presented and discussed.

  10. Evaluation of constraint methodologies applied to a shallow-flaw cruciform bend specimen tested under biaxial loading conditions

    SciTech Connect

    Bass, B.R.; McAfee, W.J.; Williams, P.T.; Pennell, W.E.

    1998-01-01

    A technology to determine shallow-flaw fracture toughness of reactor pressure vessel (RPV) steels is being developed for application to the safety assessment of RPVs containing postulated shallow surface flaws. Matrices of cruciform beam tests were developed to investigate and quantify the effects of temperature, biaxial loading, and specimen size on fracture initiation toughness of two-dimensional (constant depth), shallow surface flaws. The cruciform beam specimens were developed at Oak Ridge National Laboratory (ORNL) to introduce a prototypic, far-field. out-of-plane biaxial stress component in the test section that approximates the nonlinear stresses resulting from pressurized-thermal-shock or pressure-temperature loading of an RPV. Tests were conducted under biaxial load ratios ranging from uniaxial to equibiaxial. These tests demonstrated that biaxial loading can have a pronounced effect on shallow-flaw fracture toughness in the lower transition temperature region for RPV materials. The cruciform fracture toughness data were used to evaluate fracture methodologies for predicting the observed effects of biaxial loading on shallow-flaw fracture toughness. Initial emphasis was placed on assessment of stress-based methodologies. namely, the J-Q formulation, the Dodds-Anderson toughness scaling model, and the Weibull approach. Applications of these methodologies based on the hydrostatic stress fracture criterion indicated an effect of loading-biaxiality on fracture toughness, the conventional maximum principal stress criterion indicated no effect.

  11. Computational Reduction of Specimen Noise to Enable Improved Thermography Characterization of Flaws in Graphite Polymer Composites

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Howell, Patricia A.; Zalameda, Joseph N.

    2014-01-01

    Flaw detection and characterization with thermographic techniques in graphite polymer composites are often limited by localized variations in the thermographic response. Variations in properties such as acceptable porosity, fiber volume content and surface polymer thickness result in variations in the thermal response that in general cause significant variations in the initial thermal response. These result in a "noise" floor that increases the difficulty of detecting and characterizing deeper flaws. A method is presented for computationally removing a significant amount of the "noise" from near surface porosity by diffusing the early time response, then subtracting it from subsequent responses. Simulations of the thermal response of a composite are utilized in defining the limitations of the technique. This method for reducing the data is shown to give considerable improvement characterizing both the size and depth of damage. Examples are shown for data acquired on specimens with fabricated delaminations and impact damage.

  12. Effect of thermal profile on cyclic flaw growth in aluminum

    NASA Technical Reports Server (NTRS)

    Engstrom, W. L.

    1975-01-01

    Surface flawed and single edge notch tension specimens of 2219-T851 and -T87 aluminum were tested to determine static fracture characteristics and base line (constant amplitude, constant temperature) cyclic flaw growth behavior. Subsequent testing was then conducted in which flawed specimens were subjected to a thermal profile in which the applied stress was varied simultaneously with the temperature. The profile used represents a simplified space shuttle orbiter load/temperature flight cycle. Test temperatures included the range from 144K (-200 F) up to 450K (350 F). The measured flaw growth rates obtained from the thermal profile tests were then compared with rates predicted by assuming linear cumulative damage of base line rates.

  13. Strengths of balloon films with flaws and repairs

    NASA Technical Reports Server (NTRS)

    Portanova, M. A.

    1989-01-01

    The effects of manufacture flaws and repairs in high altitude scientific balloons was examined. A right circular cylinder was used to induce a biaxial tension-tension stress field in the polyethlene film used to manufacture these balloons. A preliminary investigation of the effect that cylinder geometry has on stress rate as a function of inflation rate was conducted. The ultimate goal was to rank, by order of degrading effects, the flaws and repairs commonly found in current high altitude balloons.

  14. Comparison of Fracture Methodologies for Flaw Stability Analysis of Storage Tanks

    SciTech Connect

    LAM, POH-SANG

    2004-04-05

    Fracture mechanics methodologies for flaw stability analysis of a storage tank were compared in terms of the maximum stable through-wall flaw sizes or ''instability lengths.'' The comparison was made at a full range of stress loading at a specific set of mechanical properties of A285 carbon steel and with the actual tank configuration. The two general methodologies, the J-integral-tearing modulus (J-T) and the failure assessment diagram (FAD), and their specific estimation schemes were evaluated. A finite element analysis of a flawed tank was also performed for validating the J estimation scheme with curvature correction and for constructing the finite element-based FAD. The calculated instability crack lengths show that the J-T methodology that uses an estimated scheme, and the material-specific FAD, most closely approximate the result calculated with finite element analysis for the stress range that bounds those expected at the highest fill levels in the storage tanks. The results from the other FAD methods show instability lengths less than the J-T results over this range.

  15. Flawed gun policy research could endanger public safety.

    PubMed

    Webster, D W; Vernick, J S; Ludwig, J; Lester, K J

    1997-06-01

    A highly publicized recent study by Lott and Mustard concludes that laws easing restrictions on licenses for carrying concealed firearms in public substantially reduce violent crime. Several serious flaws in the study render the authors' conclusions insupportable. These flaws include misclassification of gun-carrying laws, endogeneity of predictor variables, omission of confounding variables, and failure to control for the cyclical nature of crime trends. Most of these problems should bias results toward overestimating the crime-reducing effects of laws making it easier to carry concealed firearms in public. Lott and Mustard's statistical models produce findings inconsistent with criminological theories and well-established facts about crime, and subsequent reanalysis of their data challenges their conclusions. Public health professionals should understand the methodological issues raised in this commentary, particularly when flawed research could influence the introduction of policies with potentially deleterious consequences. PMID:9224169

  16. Improved Flaw Detection and Characterization with Difference Thermography

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Zalameda, Joseph N.; Howell, Patricia A.

    2011-01-01

    Flaw detection and characterization with thermographic techniques in graphite polymer composites is often limited by localized variations in the thermographic response. Variations in properties such as acceptable porosity, variations in fiber volume content and surface polymer thickness result in variations in the thermal response that in general cause significant variations in the initial thermal response. These variations result in a noise floor that increases the difficulty of detecting and characterizing deeper flaws. The paper investigates comparing thermographic responses taken before and after a change in state in a composite to improve the detection of subsurface flaws. A method is presented for registration of the responses before finding the difference. A significant improvement in the detectability is achieved by comparing the differences in response. Examples of changes in state due to application of a load and impact are presented.

  17. Enhanced Eddy-Current Detection Of Weld Flaws

    NASA Technical Reports Server (NTRS)

    Van Wyk, Lisa M.; Willenberg, James D.

    1992-01-01

    Mixing of impedances measured at different frequencies reduces noise and helps reveal flaws. In new method, one excites eddy-current probe simultaneously at two different frequencies; usually, one of which integral multiple of other. Resistive and reactive components of impedance of eddy-current probe measured at two frequencies, mixed in computer, and displayed in real time on video terminal of computer. Mixing of measurements obtained at two different frequencies often "cleans up" displayed signal in situations in which band-pass filtering alone cannot: mixing removes most noise, and displayed signal resolves flaws well.

  18. Insensitivity to Flaws Leads to Damage Tolerance in Brittle Architected Meta-Materials

    PubMed Central

    Montemayor, L. C.; Wong, W. H.; Zhang, Y.-W.; Greer, J. R.

    2016-01-01

    Cellular solids are instrumental in creating lightweight, strong, and damage-tolerant engineering materials. By extending feature size down to the nanoscale, we simultaneously exploit the architecture and material size effects to substantially enhance structural integrity of architected meta-materials. We discovered that hollow-tube alumina nanolattices with 3D kagome geometry that contained pre-fabricated flaws always failed at the same load as the pristine specimens when the ratio of notch length (a) to sample width (w) is no greater than 1/3, with no correlation between failure occurring at or away from the notch. Samples with (a/w) > 0.3, and notch length-to-unit cell size ratios of (a/l) > 5.2, failed at a lower peak loads because of the higher sample compliance when fewer unit cells span the intact region. Finite element simulations show that the failure is governed by purely tensile loading for (a/w) < 0.3 for the same (a/l); bending begins to play a significant role in failure as (a/w) increases. This experimental and computational work demonstrates that the discrete-continuum duality of architected structural meta-materials may give rise to their damage tolerance and insensitivity of failure to the presence of flaws even when made entirely of intrinsically brittle materials. PMID:26837581

  19. Insensitivity to Flaws Leads to Damage Tolerance in Brittle Architected Meta-Materials

    NASA Astrophysics Data System (ADS)

    Montemayor, L. C.; Wong, W. H.; Zhang, Y.-W.; Greer, J. R.

    2016-02-01

    Cellular solids are instrumental in creating lightweight, strong, and damage-tolerant engineering materials. By extending feature size down to the nanoscale, we simultaneously exploit the architecture and material size effects to substantially enhance structural integrity of architected meta-materials. We discovered that hollow-tube alumina nanolattices with 3D kagome geometry that contained pre-fabricated flaws always failed at the same load as the pristine specimens when the ratio of notch length (a) to sample width (w) is no greater than 1/3, with no correlation between failure occurring at or away from the notch. Samples with (a/w) > 0.3, and notch length-to-unit cell size ratios of (a/l) > 5.2, failed at a lower peak loads because of the higher sample compliance when fewer unit cells span the intact region. Finite element simulations show that the failure is governed by purely tensile loading for (a/w) < 0.3 for the same (a/l); bending begins to play a significant role in failure as (a/w) increases. This experimental and computational work demonstrates that the discrete-continuum duality of architected structural meta-materials may give rise to their damage tolerance and insensitivity of failure to the presence of flaws even when made entirely of intrinsically brittle materials.

  20. Determination of Flaw Type and Location Using an Expert Module in Ultrasonic Nondestructive Testing for Weld Inspection

    NASA Astrophysics Data System (ADS)

    Shahriari, D.; Zolfaghari, A.; Masoumi, F.

    2011-01-01

    Nondestructive evaluation is explained as nondestructive testing, nondestructive inspection, and nondestructive examination. It is a desire to determine some characteristic of the object or to determine whether the object contains irregularities, discontinuities, or flaws. Ultrasound based inspection techniques are used extensively throughout industry for detection of flaws in engineering materials. The range and variety of imperfections encountered is large, and critical assessment of location, size, orientation and type is often difficult. In addition, increasing quality requirements of new standards and codes of practice relating to fitness for purpose are placing higher demands on operators. Applying of an expert knowledge-based analysis in ultrasonic examination is a powerful tool that can help assure safety, quality, and reliability; increase productivity; decrease liability; and save money. In this research, an expert module system is coupled with ultrasonic examination (A-Scan Procedure) to determine and evaluate type and location of flaws that embedded during welding parts. The processing module of this expert system is implemented based on EN standard to classify welding defects, acceptance condition and measuring of their location via echo static pattern and image processing. The designed module introduces new system that can automate evaluating of the results of A-scan method according to EN standard. It can simultaneously recognize the number and type of defects, and determine flaw position during each scan.

  1. Unit-Sphere Anisotropic Multiaxial Stochastic-Strength Model Probability Density Distribution for the Orientation of Critical Flaws

    NASA Technical Reports Server (NTRS)

    Nemeth, Noel

    2013-01-01

    Models that predict the failure probability of monolithic glass and ceramic components under multiaxial loading have been developed by authors such as Batdorf, Evans, and Matsuo. These "unit-sphere" failure models assume that the strength-controlling flaws are randomly oriented, noninteracting planar microcracks of specified geometry but of variable size. This report develops a formulation to describe the probability density distribution of the orientation of critical strength-controlling flaws that results from an applied load. This distribution is a function of the multiaxial stress state, the shear sensitivity of the flaws, the Weibull modulus, and the strength anisotropy. Examples are provided showing the predicted response on the unit sphere for various stress states for isotropic and transversely isotropic (anisotropic) materials--including the most probable orientation of critical flaws for offset uniaxial loads with strength anisotropy. The author anticipates that this information could be used to determine anisotropic stiffness degradation or anisotropic damage evolution for individual brittle (or quasi-brittle) composite material constituents within finite element or micromechanics-based software

  2. The detection of tightly closed flaws by nondestructive testing (NDT) methods. [fatigue crack formation in aluminum alloy test specimens

    NASA Technical Reports Server (NTRS)

    Rummel, W. D.; Rathke, R. A.; Todd, P. H., Jr.; Mullen, S. J.

    1975-01-01

    Liquid penetrant, ultrasonic, eddy current and X-radiographic techniques were optimized and applied to the evaluation of 2219-T87 aluminum alloy test specimens in integrally stiffened panel, and weld panel configurations. Fatigue cracks in integrally stiffened panels, lack-of-fusion in weld panels, and fatigue cracks in weld panels were the flaw types used for evaluation. A 2319 aluminum alloy weld filler rod was used for all welding to produce the test specimens. Forty seven integrally stiffened panels containing a total of 146 fatigue cracks, ninety three lack-of-penetration (LOP) specimens containing a total of 239 LOP flaws, and one-hundred seventeen welded specimens containing a total of 293 fatigue cracks were evaluated. Nondestructive test detection reliability enhancement was evaluated during separate inspection sequences in the specimens in the 'as-machined or as-welded', post etched and post proof loaded conditions. Results of the nondestructive test evaluations were compared to the actual flaw size obtained by measurement of the fracture specimens after completing all inspection sequences. Inspection data were then analyzed to provide a statistical basis for determining the flaw detection reliability.

  3. Detection of flaws in hazelnuts using VIS/NIR spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The feasibility of VIS/NIR spectroscopy for detection of flaws in hazelnut kernels was demonstrated. Feature datasets comprising raw absorbance values, raw absorbance Ratios (Abs['1] : Abs['2]) and Differences (Abs['1] – Abs['2]) for all possible pairs of wavelengths from 306.5 nm to 1710.9 nm were ...

  4. Five Flaws of Staff Development and the Future Beyond

    ERIC Educational Resources Information Center

    Hargreaves, Andy

    2007-01-01

    Student learning and development do not occur without teacher learning and development. Not any teacher development will do, though. The old flaws of weak and wayward staff development are well-known--no staff development, in which trial and error are assumed to be enough; staff development that is all ideas and no implementation, i.e. the…

  5. A Consumer's Guide to Common Flaws in Research.

    ERIC Educational Resources Information Center

    Roberts, Dennis M.

    This brief paper presents a sequential walk through a simple research setting--a two group experiment--to indicate common but avoidable design difficulties that may jeopardize the usefulness of the data obtained. The six flaws examined are the failure to select subjects from the population to which generalizations are to be made; failure to use…

  6. Self-Selection: First a Flaw, Then a Finding.

    ERIC Educational Resources Information Center

    Elford, George

    1981-01-01

    Rather than seeing the "self-selection" factor in private school enrollment as a flaw in Coleman's study, the author views this element of private choice and commitment to learning as the key to effective education and discipline. One of three theme articles: "Reflections on the 1981 Coleman study."(SJL)

  7. Ultrasonic flaw detection using radial basis function networks (RBFNs).

    PubMed

    Gil Pita, R; Vicen, R; Rosa, M; Jarabo, M P; Vera, P; Curpian, J

    2004-04-01

    Ultrasonic flaw detection has been studied many times in the literature. Schemes based on thresholding after a previous matched filter use to be the best solution, but results obtained with this method are only satisfactory when scattering and attenuation are not considered. In this paper, we propose an alternative solution to thresholding detection method. We deal with the usage of different flaw detection methods comparing them with the proposed one. The experiment tries to determinate whether a given ultrasonic signal contains a flaw echo or not. Starting with a set of 24,000 patterns with 750 samples each one, two subsets are defined for the experiments. The first one, the training set, is used to obtain the detection parameters of the different methods, and the second one is used to test the performance of them. The proposed method is based on radial basis functions networks, one of the most powerful neural network techniques. This signal processing technique tries to find the optimal decision criterion. Comparing this method with thresholding based ones, an improvement over 25-30% is obtained, depending on the probability of false alarm. So our new method is a good alternative to flaw detection problem.

  8. Fracture assessment of HSST Plate 14 shallow-flaw cruciform bend specimens tested under biaxial loading conditions

    SciTech Connect

    Bass, B.R.; McAfee, W.J.; Williams, P.T.; Pennell, W.E.

    1998-06-01

    A technology to determine shallow-flaw fracture toughness of reactor pressure vessel (RPV) steels is being developed for application to the safety assessment of RPVs containing postulated shallow surface flaws. Matrices of cruciform beam tests were developed to investigate and quantify the effects of temperature, biaxial loading, and specimen size on fracture initiation toughness of two-dimensional (constant depth), shallow, surface flaws. The cruciform beam specimens were developed at Oak Ridge National Laboratory (ORNL) to introduce a far-field, out-of-plane biaxial stress component in the test section that approximates the nonlinear stresses resulting from pressurized-thermal-shock or pressure-temperature loading of an RPV. Tests were conducted under biaxial load ratios ranging from uniaxial to equibiaxial. These tests demonstrated that biaxial loading can have a pronounced effect on shallow-flaw fracture toughness in the lower transition temperature region for an RPV material. The cruciform fracture toughness data were used to evaluate fracture methodologies for predicting the observed effects of biaxial loading on shallow-flaw fracture toughness. Initial emphasis was placed on assessment of stress-based methodologies, namely, the J-Q formulation, the Dodds-Anderson toughness scaling model, and the Weibull approach. Applications of these methodologies based on the hydrostatic stress fracture criterion indicated an effect of loading-biaxiality on fracture toughness; the conventional maximum principal stress criterion indicated no effect. A three-parameter Weibull model based on the hydrostatic stress criterion is shown to correlate the experimentally observed biaxial effect on cleavage fracture toughness by providing a scaling mechanism between uniaxial and biaxial loading states.

  9. Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds

    SciTech Connect

    GJ Schuster, FA Simonen, SR Doctor

    2008-04-01

    The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing.

  10. Geophysics Fatally Flawed by False Fundamental Philosophy

    NASA Astrophysics Data System (ADS)

    Myers, L. S.

    2004-05-01

    For two centuries scientists have failed to realize Laplace's nebular hypothesis \\(1796\\) of Earth's creation is false. As a consequence, geophysicists today are misinterpreting and miscalculating many fundamental aspects of the Earth and Solar System. Why scientists have deluded themselves for so long is a mystery. The greatest error is the assumption Earth was created 4.6 billion years ago as a molten protoplanet in its present size, shape and composition. This assumption ignores daily accretion of more than 200 tons/day of meteorites and dust, plus unknown volumes of solar insolation that created coal beds and other biomass that increased Earth's mass and diameter over time! Although the volume added daily is minuscule compared with Earth's total mass, logic and simple addition mandates an increase in mass, diameter and gravity. Increased diameter from accretion is proved by Grand Canyon stratigraphy that shows a one kilometer increase in depth and planetary radius at a rate exceeding three meters \\(10 ft\\) per Ma from start of the Cambrian \\(540 Ma\\) to end of the Permian \\(245 Ma\\)-each layer deposited onto Earth's surface. This is unequivocal evidence of passive external growth by accretion, part of a dual growth and expansion process called "Accreation" \\(creation by accretion\\). Dynamic internal core expansion, the second stage of Accreation, did not commence until the protoplanet reached spherical shape at 500-600 km diameter. At that point, gravity-powered compressive heating initiated core melting and internal expansion. Expansion quickly surpassed the external accretion growth rate and produced surface volcanoes to relieve explosive internal tectonic pressure and transfer excess mass (magma)to the surface. Then, 200-250 Ma, expansion triggered Pangaea's breakup, first sundering Asia and Australia to form the Pacific Ocean, followed by North and South America to form the Atlantic Ocean, by the mechanism of midocean ridges, linear underwater

  11. Seven Pervasive Statistical Flaws in Cognitive Training Interventions

    PubMed Central

    Moreau, David; Kirk, Ian J.; Waldie, Karen E.

    2016-01-01

    The prospect of enhancing cognition is undoubtedly among the most exciting research questions currently bridging psychology, neuroscience, and evidence-based medicine. Yet, convincing claims in this line of work stem from designs that are prone to several shortcomings, thus threatening the credibility of training-induced cognitive enhancement. Here, we present seven pervasive statistical flaws in intervention designs: (i) lack of power; (ii) sampling error; (iii) continuous variable splits; (iv) erroneous interpretations of correlated gain scores; (v) single transfer assessments; (vi) multiple comparisons; and (vii) publication bias. Each flaw is illustrated with a Monte Carlo simulation to present its underlying mechanisms, gauge its magnitude, and discuss potential remedies. Although not restricted to training studies, these flaws are typically exacerbated in such designs, due to ubiquitous practices in data collection or data analysis. The article reviews these practices, so as to avoid common pitfalls when designing or analyzing an intervention. More generally, it is also intended as a reference for anyone interested in evaluating claims of cognitive enhancement. PMID:27148010

  12. Fan beam and double crosshole Lamb wave tomography for mapping flaws in aging aircraft structures.

    PubMed

    Malyarenko, E V; Hinders, M K

    2000-10-01

    As the worldwide aviation fleet continues to age, methods for accurately predicting the presence of structural flaws-such as hidden corrosion and disbonds-that compromise airworthiness become increasingly necessary. Ultrasonic guided waves, Lamb waves, allow large sections of aircraft structures to be rapidly inspected. However, extracting quantitative information from Lamb wave data has always involved highly trained personnel with a detailed knowledge of mechanical waveguide physics. The work summarized here focuses on a variety of different tomographic reconstruction techniques to graphically represent the Lamb wave data in quantitative maps that can be easily interpreted by technicians. Because the velocity of Lamb waves depends on thickness, for example, the traveltimes of the fundamental Lamb modes can be converted into a thickness map of the inspection region. This article describes two potentially practical implementations of Lamb wave tomographic imaging techniques that can be optimized for in-the-field testing of large-area aircraft structures. Laboratory measurements discussed here demonstrate that Lamb wave tomography using either a ring of transducers with fan beam reconstructions, or a square array of transducers with algebraic reconstruction tomography, is appropriate for detecting flaws in multilayer aircraft materials. The speed and fidelity of the reconstruction algorithms as well as practical considerations for person-portable array-based systems are discussed in this article.

  13. Technical basis for flawed cylinder test specification to assure adequate fracture resistance of ISO high strength steel cylinder

    SciTech Connect

    Rana, M.D.; Smith, J.H.; Tribolet, R.O.

    1996-12-01

    High pressure industrial gases (such as oxygen, nitrogen, argon, hydrogen, etc.) are stored and transported in portable cylinders. ISO TC58 SC3 has developed a draft specification 9809 for design and fabrication of high pressure cylinders with maximum tensile strength limitation of 1,100 N/mm{sup 2}. In order to extend the ISO 9809 rules for higher than 1,100 N/mm{sup 2} strength level cylinders, a working group WG14 was formed in 1989 to develop new rules to assure adequate fracture resistance. In 1994, WG14 recommended a simple, but unique flawed cylinder test method for design qualification of the cylinder and acceptance criteria to assure adequate fracture resistance. WG14 also recommended Charpy-V-Notch impact tests to control the required fracture resistance on production cylinders. This paper presents the technical basis that was employed in developing the flawed cylinder test method and acceptance criteria. The specification was developed for seamless steel cylinders having actual strength in the range of 1,100 to 1,400 N/mm{sup 2} and cylindrical section wall thickness in the range of 3mm to 10mm. Flawed cylinder tests were conducted on several hundred cylinders of varying sizes and strength levels. The specification requires to demonstrate LEAK-BEFORE-BREAK performance of the cylinder having flaw length equal to 1.6(O.D. {times} t{sub design}){sup 0.5} at failure pressure = (t{sub design}/t{sub actual}) {times} Design Pressure.

  14. Technical basis for flawed cylinder test specification to assure adequate fracture resistance of ISO high-strength steel cylinder

    SciTech Connect

    Rana, M.D.; Smith, J.H.; Tribolet, R.O.

    1997-11-01

    High-pressure industrial gases (such as oxygen, nitrogen, argon, hydrogen, etc.) are stored and transported in portable cylinders. ISO TC58 SC3 has developed a draft specification 9809 for design and fabrication of high-pressure cylinders with maximum tensile strength limitation of 1,100 N/mm{sup 2}. In order to extend the ISO 9809 rules for higher than 1,100 N/mm{sup 2} strength level cylinders, a working group WG14 was formed in 1989 to develop new rules to assure adequate fracture resistance. In 1994, WG14 recommended a simple, but unique flawed cylinder test method for design qualification of the cylinder and acceptance criteria to assure adequate fracture resistance. WG14 also recommended Charpy-V-notch impact tests to control the required fracture resistance on production cylinders. This paper presents the technical basis that was employed in developing the flawed cylinder test method and acceptance criteria. The specification was developed for seamless steel cylinders having actual strength in the range of 1,100 to 1,400 N/mm{sup 2} and cylindrical section wall thickness in the range of 3 to 10 mm. Flawed cylinder tests were conducted on several hundred cylinders of varying sizes and strength levels. The specification requires to demonstrate LEAK-BEFORE-BREAK performance of the cylinder having flaw length equal to 1.6 (o.d. {times} t{sub design}){sup 0.5} at failure pressure = (t{sub design}/t{sub actual}) x Design Pressure.

  15. Interaction of surface waves induced by IDT sensors with flaws in fiberglass composite panels

    NASA Astrophysics Data System (ADS)

    Na, Jeong K.; Nalladega, Vijay; Druffner, Carl

    2011-04-01

    Polyester resin based glass fiber reinforced composite panels obtained from a local windmill turbine blade part manufacturing company are used to evaluate the performance of inter-digital transducer (IDT) surface wave transducers. Interaction of surface waves with fiberglass layers is addressed in this work. Additionally, artificially created flaws such as cracks, impact damage and delamination are also studied in terms of amplitude changes in order to attempt to quantify the size, location and severity of damage in the test panels. As a potential application to the structural health monitoring (SHM) of windmill turbine blades, the coverage distance within the width of the sound field is estimated to be over 80 cm when a set of IDT sensors consisted of one transmitter and two receivers in a pitch-catch mode.

  16. Gun bore flaw image matching based on improved SIFT descriptor

    NASA Astrophysics Data System (ADS)

    Zeng, Luan; Xiong, Wei; Zhai, You

    2013-01-01

    In order to increase the operation speed and matching ability of SIFT algorithm, the SIFT descriptor and matching strategy are improved. First, a method of constructing feature descriptor based on sector area is proposed. By computing the gradients histogram of location bins which are parted into 6 sector areas, a descriptor with 48 dimensions is constituted. It can reduce the dimension of feature vector and decrease the complexity of structuring descriptor. Second, it introduce a strategy that partitions the circular region into 6 identical sector areas starting from the dominate orientation. Consequently, the computational complexity is reduced due to cancellation of rotation operation for the area. The experimental results indicate that comparing with the OpenCV SIFT arithmetic, the average matching speed of the new method increase by about 55.86%. The matching veracity can be increased even under some variation of view point, illumination, rotation, scale and out of focus. The new method got satisfied results in gun bore flaw image matching. Keywords: Metrology, Flaw image matching, Gun bore, Feature descriptor

  17. Eddy current probe and method for flaw detection in metals

    DOEpatents

    Watjen, J.P.

    1987-06-23

    A flaw detecting system is shown which includes a probe having a pair of ferrite cores with in-line gaps in close proximity to each other. An insulating, non-magnetic, non-conducting holder fills the gaps and supports the ferrite cores in a manner such that the cores form a generally V-shape. Each core is provided with an excitation winding and a detection winding. The excitation windings are connected in series or parallel with an rf port for connection thereof to a radio frequency source. The detection windings, which are differentially wound, are connected in series circuit to a detector port for connection to a voltage measuring instrument. The ferrite cores at the in-line gaps directly engage the metal surface of a test piece, and the probe is scanned along the test piece. In the presence of a flaw in the metal surface the detection winding voltages are unbalanced, and the unbalance is detected by the voltage measuring instrument. The insulating holder is provided with a profile which conforms to that of a prominent feature of the test piece to facilitate movement of the probe along the feature, typically an edge or a corner. 9 figs.

  18. Eddy current probe and method for flaw detection in metals

    DOEpatents

    Watjen, John P.

    1987-06-23

    A flaw detecting system is shown which includes a probe having a pair of ferrite cores with in-line gaps in close proximity to each other. An insulating, non-magnetic, non-conducting holder fills the gaps and supports the ferrite cores in a manner such that the cores form a generally V-shape. Each core is provided with an excitation winding and a detection winding. The excitation windings are connected in series or parallel with an rf port for connection thereof to a radio frequency source. The detection windings, which are differentially wound, are connected in series circuit to a detector port for connection to a voltage measuring instrument. The ferrite cores at the in-line gaps directly engage the metal surface of a test piece, and the probe is scanned along the test piece. In the presence of a flaw in the metal surface the detection winding voltages are unbalanced, and the unbalance is detected by the voltage measuring instrument. The insulating holder is provided with a profile which conforms to that of a prominent feature of the test piece to facilitate movement of the probe along the feature, typically an edge or a corner.

  19. Reference-frame-independent quantum key distribution with source flaws

    NASA Astrophysics Data System (ADS)

    Wang, Can; Sun, Shi-Hai; Ma, Xiang-Chun; Tang, Guang-Zhao; Liang, Lin-Mei

    2015-10-01

    Compared with the traditional protocols of quantum key distribution (QKD), the reference-frame-independent (RFI)-QKD protocol has been generally proved to be very useful and practical, since its experimental implementation can be simplified without the alignment of a reference frame. In most RFI-QKD systems, the encoding states are always taken to be perfect, which, however, is not practical in realizations. In this paper, we consider the security of RFI QKD with source flaws based on the loss-tolerant method proposed by Tamaki et al. [Phys. Rev. A 90, 052314 (2014), 10.1103/PhysRevA.90.052314]. As the six-state protocol can be realized with four states, we show that the RFI-QKD protocol can also be performed with only four encoding states instead of six encoding states in its standard version. Furthermore, the numerical simulation results show that the source flaws in the key-generation basis (Z basis) will reduce the key rate but are loss tolerant, while the ones in X and Y bases almost have no effect and the key rate remains almost the same even when they are very large. Hence, our method and results will have important significance in practical experiments, especially in earth-to-satellite or chip-to-chip quantum communications.

  20. Rotating flux-focusing eddy current probe for flaw detection

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Fulton, James P. (Inventor); Nath, Shridhar C. (Inventor); Simpson, John W. (Inventor); Namkung, Min (Inventor)

    1997-01-01

    A flux-focusing electromagnetic sensor which uses a ferromagnetic flux-focusing lens simplifies inspections and increases detectability of fatigue cracks about circular fasteners and other circular inhomogeneities in high conductivity material. The unique feature of the device is the ferrous shield isolating a high-turn pick-up coil from an excitation coil, The use of the magnetic shield is shown to produce a null voltage output across the receiving coil in the presence of an unflawed sample. A redistribution of the current flow in the sample caused by the presence of flaws, however, eliminates the shielding condition and a large output voltage is produced, yielding a clear unambiguous flaw signal. By rotating the probe in a path around a circular fastener such as a rivet while maintaining a constant distance between the probe and the center of a rivet, the signal due to current flow about the rivet can be held constant. Any further changes in the current distribution, such as due to a fatigue crack at the rivet joint, can be detected as an increase in the output voltage above that due to the flow about the rivet head.

  1. Study on flaw detectability of NDT induction thermography technique for laminated CFRP composites

    NASA Astrophysics Data System (ADS)

    Kien Bui, Huu; Wasselynck, Guillaume; Trichet, Didier; Berthiau, Gérard

    2016-01-01

    Using a 3D finite elements simulation tool, a study on the flaw detection capacity of the non destructive testing (NDT) induction thermography (IT) technique for laminated carbon fiber reinforced polymers (CFRP) composites is presented. Delamination and fiber rupture flaw occurring at the elementary-ply scale are considered. In order to reduce the impact of measurement noise on the flaw detectability, several signal processing techniques are proposed. Contribution to the topical issue "Numelec 2015 - Elected submissions", edited by Adel Razek

  2. Fatigue flaw growth behavior in stiffened and unstiffened panels loaded in biaxial tension

    NASA Technical Reports Server (NTRS)

    Beck, E. J.

    1973-01-01

    The effect was investigated of biaxial loading on the flaw growth rate of 2219-T87 aluminum alloy that would be typical of Space Shuttle cryogenic tankage design. The stress distribution and stress concentration factors for several integrally stiffened panels under various loading conditions were obtained. The flaw growth behavior of both stiffened and unstiffened panels under biaxial loading conditions was determined. The effect of a complex stress state was studied by introducing flaws in fillet areas of biaxially loaded stiffened panels.

  3. Increase in family allowances.

    PubMed

    1989-01-01

    In July 1989 the family allowance structure in Australia was changed from a 4-rate to a 2-rate structure. The new rates were increased to $A9 a week for the 1st 3 children and $A12 for each additional child. The Family Allowance Supplment rate for children 13-15 years old was raised from $A31 to $A34.10/week. PMID:12344544

  4. Profitable failure: antidepressant drugs and the triumph of flawed experiments.

    PubMed

    McGoey, Linsey

    2010-01-01

    Drawing on an analysis of Irving Kirsch and colleagues' controversial 2008 article in "PLoS [Public Library of Science] Magazine" on the efficacy of SSRI antidepressant drugs such as Prozac, I examine flaws within the methodologies of randomized controlled trials (RCTs) that have made it difficult for regulators, clinicians and patients to determine the therapeutic value of this class of drug. I then argue, drawing analogies to work by Pierre Bourdieu and Michael Power, that it is the very limitations of RCTs -- their inadequacies in producing reliable evidence of clinical effects -- that help to strengthen assumptions of their superiority as methodological tools. Finally, I suggest that the case of RCTs helps to explore the question of why failure is often useful in consolidating the authority of those who have presided over that failure, and why systems widely recognized to be ineffective tend to assume greater authority at the very moment when people speak of their malfunction.

  5. 'Moral distress'--time to abandon a flawed nursing construct?

    PubMed

    Johnstone, Megan-Jane; Hutchinson, Alison

    2015-02-01

    Moral distress has been characterised in the nursing literature as a major problem affecting nurses in all healthcare systems. It has been portrayed as threatening the integrity of nurses and ultimately the quality of patient care. However, nursing discourse on moral distress is not without controversy. The notion itself is conceptually flawed and suffers from both theoretical and practical difficulties. Nursing research investigating moral distress is also problematic on account of being methodologically weak and disparate. Moreover, the ultimate purpose and significance of the research is unclear. In light of these considerations, it is contended that the notion of moral distress ought to be abandoned and that concerted attention be given to advancing inquiries that are more conducive to improving the quality and safety of moral decision-making, moral conduct and moral outcomes in nursing and healthcare domains.

  6. Flaw Tolerance in Lap Shear Brazed Joints. Part 1

    NASA Technical Reports Server (NTRS)

    Flom, Yury; Wang, Li-Qin

    2003-01-01

    Furnace brazing is a joining process used in the aerospace and other industries to produce strong permanent and hermetic structural joints. As in any joining process, brazed joints have various imperfections and defects. At the present time, our understanding of the influence of the internal defects on the strength of the brazed joints is not adequate. The goal of this 3-part investigation is to better understand the properties and failure mechanisms of the brazed joints containing defects. This study focuses on the behavior of the brazed lap shear joints because of their importance in manufacturing aerospace structures. In Part 1, an average shear strength capability and failure modes of the single lap joints are explored. Stainless steel specimens brazed with pure silver are tested in accordance with the AWS C3.2 standard. Comparison of the failure loads and the ultimate shear strength with the Finite Element Analysis (FEA) of the same specimens as a function of the overlap widths shows excellent correlation between the experimental and calculated values for the defect-free lap joints. A damage zone criterion is shown to work quite well in understanding the failure of the braze joints. In Part 2, the findings of the Part 1 will be verified on the larger test specimens. Also, various flaws will be introduced in the test specimens to simulate lack of braze coverage in the lap joints. Mechanical testing and FEA will be performed on these joints to verify that behavior of the flawed ductile lap joints is similar to joints with a reduced braze area. Finally, in Part 3, the results obtained in Parts 1 and 2 will be applied to the actual brazed structure to evaluate the load-carrying capability of a structural lap joint containing discontinuities. In addition, a simplified engineering procedure will be offered for the laboratory testing of the lap shear specimens.

  7. Acoustic-emission signal-processing analog unit for locating flaws in large tanks

    NASA Technical Reports Server (NTRS)

    Moskal, F. J.; Fageol, J. D.

    1973-01-01

    Technique monitors structural flaws in 105-in. diameter tanks. Tank surface is divided into many areas and each area is sectioned into 20 equilateral triangles that form icosahedron. Twelve transducers are equally positioned on tank surface at vertex of each triangle. Transducers monitor area for flaws by detecting any increase in acoustical activity.

  8. Evaluation of outer flaws in titanium alloys using eddy current measuring system

    SciTech Connect

    Chady, T.; Psuj, G.; Kowalczyk, J.

    2011-06-23

    In this paper results of shallow outer flaw detection in thick titanium alloy specimens is presented. In order to increase efficiency of inspections of minor defects an eddy current measuring system with a lock-in amplifier was used. The measurements were carried out for flat and cylindrical specimens with artificial flaws.

  9. Holographic and ultrasonic detection of bond flaws in aluminum panels reinforced with boron-epoxy

    NASA Technical Reports Server (NTRS)

    Platt, R. J., Jr.; Thurston, L. B., Jr.

    1974-01-01

    An experimental investigation was made of the application of holographic interferometry to the nondestructive detection of unbonded areas (flaws) in bonded panels. Flaw detection results were compared with results obtained with an ultrasonic flaw detector. Holography, with panel deformation accomplished by a reduction in ambient pressure, is less sensitive for flaws beneath 5 and 10 plies of boron-epoxy than the ultrasonic method, though it does have its operational advantages. A process for the manufacture of bonded panels which incorporate known unbonded areas was also developed. The unbonded areas were formed without the use of foreign materials, which makes the method suitable for the construction of reference standards for bonded panels whenever needed for the proper setup of ultrasonic flaw-detection instruments.

  10. Quantification technology study on flaws in steam-filled pipelines based on image processing

    NASA Astrophysics Data System (ADS)

    Sun, Lina; Yuan, Peixin

    2009-07-01

    Starting from exploiting the applied detection system of gas transmission pipeline, a set of X-ray image processing methods and pipeline flaw quantificational evaluation methods are proposed. Defective and non-defective strings and rows in gray image were extracted and oscillogram was obtained. We can distinguish defects in contrast with two gray images division. According to the gray value of defects with different thicknesses, the gray level depth curve is founded. Through exponential and polynomial fitting way to obtain the attenuation mathematical model which the beam penetrates pipeline, thus attain flaw deep dimension. This paper tests on the PPR pipe in the production of simulated holes flaw and cracks flaw, 135KV used the X-ray source on the testing. Test results show that X-ray image processing method, which meet the needs of high efficient flaw detection and provide quality safeguard for thick oil recovery, can be used successfully in detecting corrosion of insulated pipe.

  11. Stress intensity factors for long, deep surface flaws in plates under extensional fields

    NASA Technical Reports Server (NTRS)

    Harms, A. E.; Smith, C. W.

    1973-01-01

    Using a singular solution for a part circular crack, a Taylor Series Correction Method (TSCM) was verified for extracting stress intensity factors from photoelastic data. Photoelastic experiments were then conducted on plates with part circular and flat bottomed cracks for flaw depth to thickness ratios of 0.25, 0.50 and 0.75 and for equivalent flaw depth to equivalent ellipse length values ranging from 0.066 to 0.319. Experimental results agreed well with the Smith theory but indicated that the use of the ''equivalent'' semi-elliptical flaw results was not valid for a/2c less than 0.20. Best overall agreement for the moderate (a/t approximately 0.5) to deep flaws (a/t approximatelly 0.75) and a/2c greater than 0.15 was found with a semi-empirical theory, when compared on the basis of equivalent flaw depth and area.

  12. Usability Flaws in Medication Alerting Systems: Impact on Usage and Work System

    PubMed Central

    Ammenwerth, E.; Roehrer, E.; Pelayo, S.; Vasseur, F.; Beuscart-Zéphir, M.-C.

    2015-01-01

    Summary Objectives Previous research has shown that medication alerting systems face usability issues. There has been no previous attempt to systematically explore the consequences of usability flaws in such systems on users (i.e. usage problems) and work systems (i.e. negative outcomes). This paper aims at exploring and synthesizing the consequences of usability flaws in terms of usage problems and negative outcomes on the work system. Methods A secondary analysis of 26 papers included in a prior systematic review of the usability flaws in medication alerting was performed. Usage problems and negative outcomes were extracted and sorted. Links between usability flaws, usage problems, and negative outcomes were also analyzed. Results Poor usability generates a large variety of consequences. It impacts the user from a cognitive, behavioral, emotional, and attitudinal perspective. Ultimately, usability flaws have negative consequences on the workflow, the effectiveness of the technology, the medication management process, and, more importantly, patient safety. Only few complete pathways leading from usability flaws to negative outcomes were identified. Conclusion Usability flaws in medication alerting systems impede users, and ultimately their work system, and negatively impact patient safety. Therefore, the usability dimension may act as a hidden explanatory variable that could explain, at least partly, the (absence of) intended outcomes of new technology. PMID:26123906

  13. Light-induced stress relief to improve flaw tolerance in network polymers

    SciTech Connect

    Long, Kevin N.; Dunn, Martin L.; Scott, Timothy F.; Turpin, Lucas P.; Qi, H. Jerry

    2010-03-15

    We demonstrate the ability to use photoactivated stress relaxation to improve flaw tolerance in network polymers. Unlike most self-healing polymers, which effectively close flaws by locally introducing healing agents (such as uncured resins), here light is used to relax elevated stresses around a flaw before it reaches a critical state, which reduces the threat that the flaw poses to the structural integrity of the material. In this study, we fabricate specimens with well-defined flaws and uniaxially stretch them to failure. By irradiating the specimens with UV light (365 nm) before failure, the nominal strain at failure is increased by 70% and the corresponding nominal stress is increased by 30% compared with nonirradiated specimens. To better understand the phenomena that occur at the multiaxial stress state at the flaw, we model the photomechanics using a recently developed finite element approach that accurately describes the light propagation, photochemistry, radical-induced network evolution, and the mechanical behavior of the material. Model predictions agree well with the experimental results and elucidate the role that photoinduced stress relaxation has on improving flaw tolerance.

  14. Your Flaws Are My Pain: Linking Empathy To Vicarious Embarrassment

    PubMed Central

    Krach, Sören; Cohrs, Jan Christopher; de Echeverría Loebell, Nicole Cruz; Kircher, Tilo; Sommer, Jens; Jansen, Andreas; Paulus, Frieder Michel

    2011-01-01

    People vicariously experience embarrassment when observing others' public pratfalls or etiquette violations. In two consecutive studies we investigated the subjective experience and the neural correlates of vicarious embarrassment for others in a broad range of situations. We demonstrated, first, that vicarious embarrassment was experienced regardless of whether the observed protagonist acted accidentally or intentionally and was aware or unaware that he/she was in an embarrassing situation. Second, using functional magnetic resonance imaging (fMRI), we showed that the anterior cingulate cortex and the left anterior insula, two cortical structures typically involved in vicarious feelings of others' pain, are also strongly implicated in experiencing the ‘social pain’ for others' flaws and pratfalls. This holds true even for situations that engage protagonists not aware of their current predicament. Importantly, the activity in the anterior cingulate cortex and the left anterior insula positively correlated with individual differences in trait empathy. The present findings establish the empathic process as a fundamental prerequisite for vicarious embarrassment experiences, thus connecting affect and cognition to interpersonal processes. “When we are living with people who have a delicate sense of propriety, we are in misery on their account when anything unbecoming is committed. So I always feel for and with Charlotte when a person is tipping his chair. She cannot endure it.” [Elective Affinities, J. W. Goethe]. PMID:21533250

  15. Medical equipment donations in Haiti: flaws in the donation process.

    PubMed

    Dzwonczyk, Roger; Riha, Chris

    2012-04-01

    The magnitude 7.0 earthquake that struck Haiti on 12 January 2010 devastated the capital city of Port-au-Prince and the surrounding area. The area's hospitals suffered major structural damage and material losses. Project HOPE sought to rebuild the medical equipment and clinical engineering capacity of the country. A team of clinical engineers from the United States of America and Haiti conducted an inventory and assessment of medical equipment at seven public hospitals affected by the earthquake. The team found that only 28% of the equipment was working properly and in use for patient care; another 28% was working, but lay idle for technical reasons; 30% was not working, but repairable; and 14% was beyond repair. The proportion of equipment in each condition category was similar regardless of whether the equipment was present prior to the earthquake or was donated afterwards. This assessment points out the flaws that existed in the medical equipment donation process and reemphasizes the importance of the factors, as delineated by the World Health Organization more than a decade ago, that constitute a complete medical equipment donation.

  16. High-temperature flaw assessment procedure: Interim report

    SciTech Connect

    Ruggles, M.B.; Takahashi, Y.; Ainsworth, R.A.

    1989-08-01

    The current program represents a joint effort between the Electric Power Research Institute (EPRI) in the USA, the Central Research Institute of Electric Power Industry (CRIEPI) in Japan, and the Central Electricity Generating Board (CEGB) in the UK. The goal is to develop an interim high-temperature flaw assessment procedure for high-temperature reactor components. This is to be accomplished through exploratory experimental and analytical studies of high-temperature crack growth. The state-of-the-art assessment and the fracture mechanics database for both types 304 and 316 stainless steels, completed in 1988, serve as a foundation for the present work. Work in the three participating organizations is progressing roughly on schedule. Results to-date are presented in this document. Fundamental tests results are discussed in Section 2. Section 3 focuses on results of exploratory subcritical crack growth tests. Progress in subcritical crack growth modeling is reported in Section 4. Exploratory failure tests are outlined in Section 5. 21 refs., 70 figs., 7 tabs.

  17. Progress in evaluation and improvement in nondestructive examination reliability for inservice inspection of Light Water Reactors (LWRs) and characterize fabrication flaws in reactor pressure vessels

    SciTech Connect

    Doctor, S.R.; Bowey, R.E.; Good, M.S.; Friley, J.R.; Kurtz, R.J.; Simonen, F.A.; Taylor, T.T.; Heasler, P.G.; Andersen, E.S.; Diaz, A.A.; Greenwood, M.S.; Hockey, R.L.; Schuster, G.J.; Spanner, J.C.; Vo, T.V.

    1991-10-01

    This paper is a review of the work conducted under two programs. One (NDE Reliability Program) is a multi-year program addressing the reliability of nondestructive evaluation (NDE) for the inservice inspection (ISI) of light water reactor components. This program examines the reliability of current NDE, the effectiveness of evolving technologies, and provides assessments and recommendations to ensure that the NDE is applied at the right time, in the right place with sufficient effectiveness that defects of importance to structural integrity will be reliably detected and accurately characterized. The second program (Characterizing Fabrication Flaws in Reactor Pressure Vessels) is assembling a data base to quantify the distribution of fabrication flaws that exist in US nuclear reactor pressure vessels with respect to density, size, type, and location. These programs will be discussed as two separate sections in this report. 4 refs., 7 figs.

  18. The problem of the second wind turbine - a note on a common but flawed wind power estimation method

    NASA Astrophysics Data System (ADS)

    Gans, F.; Miller, L. M.; Kleidon, A.

    2010-06-01

    Several recent wind power estimates suggest how this renewable resource can meet all of the current and future global energy demand with little impact on the atmosphere. These estimates are calculated using observed wind speeds in combination with specifications of wind turbine size and density to quantify the extractable wind power. Here we show that this common methodology is flawed because it does not account for energy removal by the turbines that is necessary to ensure the conservation of energy. We will first illustrate the common but flawed methodology using parameters from a recent global quantification of wind power in a simple experimental setup. For a small number of turbines at small scales, the conservation of energy hardly results in a difference when compared to the common method. However, when applied at large to global scales, the ability of radiative gradients to generate a finite amount of kinetic energy needs to be taken into account. Using the same experimental setup, we use the simplest method to ensure the conservation of energy to show a non-negligble decrease in wind velocity after the first turbine that will successively result in lower extraction of the downwind turbines. We then show how the conservation of energy inevitably results in substantially lower estimates of wind power at the global scale. Because conservation of energy is fundamental, we conclude that ultimately environmental constraints set the upper limit for wind power availability at the larger scale rather than detailed engineering specifications of the wind turbine design and placement.

  19. The probability of flaw detection and the probability of false calls in nondestructive evaluation equipment

    NASA Technical Reports Server (NTRS)

    Temple, Enoch C.

    1994-01-01

    The space industry has developed many composite materials that have high durability in proportion to their weights. Many of these materials have a likelihood for flaws that is higher than in traditional metals. There are also coverings (such as paint) that develop flaws that may adversely affect the performance of the system in which they are used. Therefore there is a need to monitor the soundness of composite structures. To meet this monitoring need, many nondestructive evaluation (NDE) systems have been developed. An NDE system is designed to detect material flaws and make flaw measurements without destroying the inspected item. Also, the detection operation is expected to be performed in a rapid manner in a field or production environment. Some of the most recent video-based NDE methodologies are shearography, holography, thermography, and video image correlation.

  20. Fracture characteristics of structural aerospace alloys containing deep surface flaws. [aluminum-titanium alloys

    NASA Technical Reports Server (NTRS)

    Masters, J. N.; Bixler, W. D.; Finger, R. W.

    1973-01-01

    Conditions controlling the growth and fracture of deep surface flaws in aerospace alloys were investigated. Static fracture tests were performed on 7075-T651 and 2219-T87 aluminum, and 6Ai-4V STA titanium . Cyclic flaw growth tests were performed on the two latter alloys, and sustain load tests were performed on the titanium alloy. Both the cyclic and the sustain load tests were performed with and without a prior proof overload cycle to investigate possible growth retardation effects. Variables included in all test series were thickness, flaw depth-to-thickness ratio, and flaw shape. Results were analyzed and compared with previously developed data to determine the limits of applicability of available modified linear elastic fracture solutions.

  1. A Knowledge Based Expert System to Aid Theoretical Ultrasonic Flaw Modelling

    NASA Astrophysics Data System (ADS)

    Robinson, Robert J.; McNab, Alistair

    2005-04-01

    This paper describes the culmination of three years work at the University of Strathclyde in developing an Expert System to aid theoretical flaw modelling. The Expert System utilises four validated models to simulate flaw modelling scenarios. Under certain conditions the models may break down and produce flaw responses which cannot be considered accurate. Previously a suitably qualified NDT engineer would have to interpret these results and update the original flaw model simulation in order to produce valid results. This was a laborious process and was restricted to those persons who had an in-depth knowledge in the operation of the validated models. The Expert System is capable of interpreting these warning flags and updating the original simulation to produce a valid modelling scenario. This paper gives a brief outline of how the Expert System operates before comparing the response of the system to that of a suitable qualified NDT engineer for a number of defect scenarios.

  2. Effects of flaws on fracture behavior of structural ceramics

    SciTech Connect

    Singh, J.P.; Singh, D.; Sutaria, M.

    1996-05-01

    We evaluated the effects of fiber coating thickness, fiber orientation, and elevated temperature on flaw morphology and mechanical properties of Nicalon-fiber-reinforced SiC matrix composites with fiber cloth lay-up sequences of 0{degree}/45{degrees}, 0{degree}/20{degrees}/60{degrees}, and 0{degree}/40{degrees}/60{degrees} and fiber coating thicknesses of 0. 2 and 0.4{mu}m. For the three fiber cloth lay-up sequences (0{degree}/45{degrees}, 0{degree}/20{degrees}/60{degrees}, and 0{degree}/40{degrees}/60{degrees}), mechanical property (first matrix cracking stress, ultimate stress, and work of fracture) initially increase with coating thickness and reach peak values at a coating thickness of 0.2{mu}m. A further increase in coating thickness does not result in further improvements in mechanical properties; this is related to the role of coatings in protecting fibers from damage during composite processing. Measured values of strength and work-of- fracture of the above composites at elevated temperatures increased with temperature up to 1200{degrees}C, but decreased at higher temperatures. This decrease is correlated to in-situ fiber strength and fiber/matrix interface degradation. Correlations between model prediction and measured room-temperature ultimate strength of composites with 0{degree}45{degrees} and 0{degree}/40{degrees}/60{degrees} lay-up sequences were established by using in-situ fiber strength characteristics. The failure modes and degradation mechanisms in hot-gas filters and ceramic composite joints are being characterized by the mechanical and fractographic evaluation techniques established thus far. Correlations of these results with those of nondestructive evaluation can provide critical information for improved quality control.

  3. SIMULATIONS OF THE THERMOGRAPHIC RESPONSE OF NEAR SURFACE FLAWS IN REINFORCED CARBON-CARBON PANELS

    SciTech Connect

    Winfree, William P.; Howell, Patricia A.; Burke, Eric R.

    2010-02-22

    Thermographic inspection is a viable technique for detecting in-service damage in reinforced carbon-carbon (RCC) composites that are used for thermal protection in the leading edge of the shuttle orbiter. A thermographic technique for detection of near surface flaws in RCC composite structures is presented. A finite element model of the heat diffusion in structures with expected flaw configurations is in good agreement with the experimental measurements.

  4. Identify Structural Flaw Location and Type with an Inverse Algorithm of Resonance Inspection

    SciTech Connect

    Xu, Wei; Lai, Canhai; Sun, Xin

    2015-10-20

    To evaluate the fitness-for-service of a structural component and to quantify its remaining useful life, aging and service-induced structural flaws must be quantitatively determined in service or during scheduled maintenance shutdowns. Resonance inspection (RI), a non-destructive evaluation (NDE) technique, distinguishes the anomalous parts from the good parts based on changes in the natural frequency spectra. Known for its numerous advantages, i.e., low inspection cost, high testing speed, and broad applicability to complex structures, RI has been widely used in the automobile industry for quality inspection. However, compared to other contemporary direct visualization-based NDE methods, a more widespread application of RI faces a fundamental challenge because such technology is unable to quantify the flaw details, e.g. location, dimensions, and types. In this study, the applicability of a maximum correlation-based inverse RI algorithm developed by the authors is further studied for various flaw cases. It is demonstrated that a variety of common structural flaws, i.e. stiffness degradation, voids, and cracks, can be accurately retrieved by this algorithm even when multiple different types of flaws coexist. The quantitative relations between the damage identification results and the flaw characteristics are also developed to assist the evaluation of the actual state of health of the engineering structures.

  5. Comparative study on submillimeter flaws in stitched T-joint carbon fiber reinforced polymer by infrared thermography, microcomputed tomography, ultrasonic c-scan and microscopic inspection

    NASA Astrophysics Data System (ADS)

    Zhang, Hai; Hassler, Ulf; Genest, Marc; Fernandes, Henrique; Robitaille, Francois; Ibarra-Castanedo, Clemente; Joncas, Simon; Maldague, Xavier

    2015-10-01

    Stitching is used to reduce dry-core (incomplete infusion of T-joint core) and reinforce T-joint structure. However, it may cause new types of flaws, especially submillimeter flaws. Microscopic inspection, ultrasonic c-scan, pulsed thermography, vibrothermography, and laser spot thermography are used to investigate the internal flaws in a stitched T-joint carbon fiber-reinforced polymer (CFRP) matrix composites. Then, a new microlaser line thermography is proposed. Microcomputed tomography (microCT) is used to validate the infrared results. A comparison between microlaser line thermography and microCT is performed. It was concluded that microlaser line thermography can detect the internal submillimeter defects. However, the depth and size of the defects can affect the detection results. The microporosities with a diameter of less than 54 μm are not detected in the microlaser line thermography results. Microlaser line thermography can detect the microporosity (a diameter of 0.162 mm) from a depth of 90 μm. However, it cannot detect the internal microporosity (a diameter of 0.216 mm) from a depth of 0.18 mm. The potential causes are given. Finally, a comparative study is conducted.

  6. A FRAMEWORK TO DEVELOP FLAW ACCEPTANCE CRITERIA FOR STRUCTURAL INTEGRITY ASSESSMENT OF MULTIPURPOSE CANISTERS FOR EXTENDED STORAGE OF USED NUCLEAR FUEL

    SciTech Connect

    Lam, P.; Sindelar, R.; Duncan, A.; Adams, T.

    2014-04-07

    A multipurpose canister (MPC) made of austenitic stainless steel is loaded with used nuclear fuel assemblies and is part of the transfer cask system to move the fuel from the spent fuel pool to prepare for storage, and is part of the storage cask system for on-site dry storage. This weld-sealed canister is also expected to be part of the transportation package following storage. The canister may be subject to service-induced degradation especially if exposed to aggressive environments during possible very long-term storage period if the permanent repository is yet to be identified and readied. Stress corrosion cracking may be initiated on the canister surface in the welds or in the heat affected zone because the construction of MPC does not require heat treatment for stress relief. An acceptance criteria methodology is being developed for flaw disposition should the crack-like defects be detected by periodic Inservice Inspection. The external loading cases include thermal accident scenarios and cask drop conditions with the contribution from the welding residual stresses. The determination of acceptable flaw size is based on the procedure to evaluate flaw stability provided by American Petroleum Institute (API) 579 Fitness-for-Service (Second Edition). The material mechanical and fracture properties for base and weld metals and the stress analysis results are obtained from the open literature such as NUREG-1864. Subcritical crack growth from stress corrosion cracking (SCC), and its impact on inspection intervals and acceptance criteria, is not addressed.

  7. Quantification technology study on flaws in steam-filled pipelines based on image processing

    NASA Astrophysics Data System (ADS)

    Yuan, Pei-xin; Cong, Jia-hui; Chen, Bo

    2008-03-01

    Starting from exploiting the applied detection system of gas transmission pipeline, a set of X-ray image processing methods and pipeline flaw quantificational evaluation methods are proposed. Defective and non-defective strings and rows in gray image were extracted and oscillogram was obtained. We can distinguish defects in contrast with two gray images division. According to the gray value of defects with different thicknesses, the gray level depth curve is founded. Through exponential and polynomial fitting way to obtain the attenuation mathematical model which the beam penetrates pipeline, thus attain flaw deep dimension. This paper tests on the PPR pipe in the production of simulated holes flaw and cracks flaw. The X-ray source tube voltage was selected as 130kv and valve current was 1.5mA.Test results show that X-ray image processing methods, which meet the needs of high efficient flaw detection and provide quality safeguard for thick oil recovery, can be used successfully in detecting corrosion of insulated pipe.

  8. The detection of flaws in austenitic welds using the decomposition of the time-reversal operator

    NASA Astrophysics Data System (ADS)

    Cunningham, Laura J.; Mulholland, Anthony J.; Tant, Katherine M. M.; Gachagan, Anthony; Harvey, Gerry; Bird, Colin

    2016-04-01

    The non-destructive testing of austenitic welds using ultrasound plays an important role in the assessment of the structural integrity of safety critical structures. The internal microstructure of these welds is highly scattering and can lead to the obscuration of defects when investigated by traditional imaging algorithms. This paper proposes an alternative objective method for the detection of flaws embedded in austenitic welds based on the singular value decomposition of the time-frequency domain response matrices. The distribution of the singular values is examined in the cases where a flaw exists and where there is no flaw present. A lower threshold on the singular values, specific to austenitic welds, is derived which, when exceeded, indicates the presence of a flaw. The detection criterion is successfully implemented on both synthetic and experimental data. The datasets arising from welds containing a flaw are further interrogated using the decomposition of the time-reversal operator (DORT) method and the total focusing method (TFM), and it is shown that images constructed via the DORT algorithm typically exhibit a higher signal-to-noise ratio than those constructed by the TFM algorithm.

  9. The detection of flaws in austenitic welds using the decomposition of the time-reversal operator

    PubMed Central

    Cunningham, Laura J.; Mulholland, Anthony J.; Gachagan, Anthony; Harvey, Gerry; Bird, Colin

    2016-01-01

    The non-destructive testing of austenitic welds using ultrasound plays an important role in the assessment of the structural integrity of safety critical structures. The internal microstructure of these welds is highly scattering and can lead to the obscuration of defects when investigated by traditional imaging algorithms. This paper proposes an alternative objective method for the detection of flaws embedded in austenitic welds based on the singular value decomposition of the time-frequency domain response matrices. The distribution of the singular values is examined in the cases where a flaw exists and where there is no flaw present. A lower threshold on the singular values, specific to austenitic welds, is derived which, when exceeded, indicates the presence of a flaw. The detection criterion is successfully implemented on both synthetic and experimental data. The datasets arising from welds containing a flaw are further interrogated using the decomposition of the time-reversal operator (DORT) method and the total focusing method (TFM), and it is shown that images constructed via the DORT algorithm typically exhibit a higher signal-to-noise ratio than those constructed by the TFM algorithm. PMID:27274683

  10. Biaxial loading and shallow-flaw effects on crack-tip constraint and fracture-toughness

    SciTech Connect

    Pennell, W.E.; Bass, B.R.; Bryson, J.W.; McAfee, W.J.; Theiss, T.J.; Rao, M.C.

    1993-12-01

    Uniaxial tests of single-edged notched bend (SENB) specimens with both deep- and shallow-flaws have shown elevated fracture-toughness for the shallow flaws. The elevation in fracture-toughness for shallow flaws has been shown to be the result of reduced constraint at the crack-tip. Biaxial loading has the potential to increase constraint at the crack-tip and thereby reduce some of the shallow-flaw, fracture-toughness elevation. Biaxial fracture-toughness tests have shown that the shallow-flaw, fracture-toughness elevation is reduced but not eliminated by biaxial loading. Dual-parameter, fracture-toughness correlations have been proposed to reflect the effect of crack-tip constraint on fracture-toughness. Test results from the uniaxial and biaxial tests were analyzed using the dual-parameter technology. Discrepancies between analysis results and cleavage initiation site data from fractographic examinations indicate that the analysis models are in need of further refinement. Addition of a precleavage, ductile-tearing element to the analysis model has the potential to resolve the noted discrepancies.

  11. Biaxial loading and shallow-flaw effects on crack-tip constraint and fracture-toughness

    SciTech Connect

    Pennell, W.E.; Bass, B.R.; Bryson, J.W.; McAfee, W.J.; Theiss, T.J.; Rao, M.C.

    1994-04-01

    Uniaxial tests of single-edged notched bend (SENB) specimens with both deep- and shallow-flaws have shown elevated fracturetoughness for the shallow flaws. The elevation in fracture-toughness for shallow flaws has been shown to be the result of reduced constraint at the crack-tip. Biaxial loading has the potential to increase constraint at the crack-tip and thereby reduce some of the shallow-flaw, fracture-toughness elevation. Biaxial fracture-toughness tests have shown that the shallow-flaw, fracture-toughness elevation is reduced but not eliminated by biaxial loading. Dual-parameter, fracture-toughness correlations have been proposed to reflect the effect of crack-tip constraint on fracture-toughness. Test results from the uniaxial and biaxial tests were analyzed using the dual-parameter technology. Discrepancies between analysis results and cleavage initiation site data from fractographic examinations indicate that the analysis models are in need of further refinement. Addition of a precleavage, ductile-tearing element to the analysis model has the potential to resolve the noted discrepancies.

  12. 40 CFR 35.2025 - Allowance and advance of allowance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... advance of allowance. (a) Allowance. Step 2+3 and Step 3 grant agreements will include an allowance for facilities planning and design of the project and Step 7 agreements will include an allowance for facility... would receive under paragraph (a) of this section. (5) In the event a Step 2+3, Step 3 or Step 7...

  13. Three-dimensional reconstruction of surface-breaking flaws using finite element methods

    NASA Astrophysics Data System (ADS)

    Gladchtein, R. Schifini; Bruno, A. C.

    2000-05-01

    We present an iterative algorithm that reconstructs the geometry of three-dimensional surface-breaking flaws from measurements using an NDE magnetic flux leakage technique. Several surface-breaking flaws in a ferromagnetic sample have been modeled using the finite element method and later reconstructed by an optimization routine. This reconstruction was achieved by modifying the coordinates of several surface nodes of the finite element mesh, solving the magnetostatic problem, and optimizing it by a least-squares method. The magnetic field was measured above the surface of the sample. This inverse solution algorithm might be particularly useful to characterize flaws detected by magnetic in-line inspection tools in oil and gas pipelines.

  14. Flaw density examinations of a clad boiling water reactor pressure vessel segment

    SciTech Connect

    Cook, K.V.; McClung, R.W.

    1986-01-01

    Flaw density is the greatest uncertainty involved in probabilistic analyses of reactor pressure vessel failure. As part of the Heavy-Section Steel Technology (HSST) Program, studies have been conducted to determine flaw density in a section of reactor pressure vessel cut from the Hope Creek Unit 2 vessel (nominally 0.7 by 3 m (2 by 10 ft)). This section (removed from the scrapped vessel that was never in service) was evaluated nondestructively to determine the as-fabricated status. We had four primary objectives: (1) evaluate longitudinal and girth welds for flaws with manual ultrasonics, (2) evaluate the zone under the nominal 6.3-mm (0.25-in.) clad for cracking (again with manual ultrasonics), (3) evaluate the cladding for cracks with a high-sensitivity fluorescent penetrant method, and (4) determine the source of indications detected.

  15. Pipe Axial Flaw Failure Criteria (PAFFC): Version 1.0 user`s manual and software

    SciTech Connect

    Leis, B.N.; Ghadiali, N.D.

    1994-05-04

    This topical report is the technical manual and basis for delivery of the software tided Pipe Axial Flaw Failure Criterion. This criterion was developed under SI Task 1. 13 for the Line Pipe Research Supervisory Committee of the Pipeline Research Committee. This software has been given the acronym PAFFC, which follows from the underlined letters in the title for this code. The purpose of PAFFC is to determine the failure conditions associated with a single external axial flaw in a gas transmission pipeline. Failure is determined concurrently in terms of two independent failure processes - fracture and/or net-section (plastic) collapse of the ligament between the flaw and the inside surface of the pipe.

  16. Investigation and characterization of constraint effects on flaw growth during fatigue loading of composite materials

    NASA Technical Reports Server (NTRS)

    Stinchcomb, W. W.; Reifsnider, K. L.; Yeung, P.; Gibbins, M. N.

    1979-01-01

    An investigative program is presented in an attempt to add to the current understanding of constraint effects on the response of composite materials under cyclic loading. The objectives were: (1) to use existing data and to develop additional data in order to establish an understanding and quantitative description of flaw growth in unidirectional lamina under cyclic loading at different load direction to fiber direction angles; (2) to establish a similar understanding and description of flaw growth in lamina which are embedded in laminates between other unflawed lamina; (3) to determine the nature of the influence of constraint on flaw growth by quantitatively comparing the results of the tests; and (4) to develop a model and philosophy of constraints effects based on our investigative results.

  17. The International Polar Year (IPY) Circumpolar Flaw Lead (CFL) system study.

    NASA Astrophysics Data System (ADS)

    Barber, D. G.; Iacozza, J.

    2009-04-01

    The International Polar Year (IPY) Circumpolar Flaw Lead (CFL) system study supported a large multidisciplinary overwintering in the Banks Island (NT) flaw lead over the period September 2007 to August 2008. The CFL system is formed when the central pack ice (which is mobile) moves away from coastal fast ice, opening a flaw lead. The CFL forms in the fall and continues as thin ice or open water throughout the winter. The flaw lead is circumpolar, with recurrent and interconnected polynyas occurring throughout the Arctic. The overarching objectives of the CFL project were to contrast the physical and biological systems of the flaw lead open water and thin ice to the adjacent landfast ice cover. The Canadian Research Icebreaker (NGCC Amundsen) completed the first-ever overwintering of a research icebreaker in the flaw lead. She supported a total of 11,000 person days distributed across 295 investigators from 28 different countries, making the CFL project the largest single IPY effort in the northern hemisphere. The project obtained many first-ever measurements of a complete suite of physical, biogeochemical, contaminant and marine ecosystem variables across the open water - fast ice contrast. Throughout the project we recognized that Inuvialuit and western science have two different ways of understanding the dramatic changes that are occurring in this sector of the Arctic. This ‘two-ways-of-knowing' saw the integration of traditional knowledge studies with the science teams onboard the Amundsen. We present information on the design of the project, an overview of the sampling program completed, highlight the scientific programs conducted, and provide some preliminary results. We conclude with an overview of the various outreach programs including a World Federation of Science Journalists (WFSJ) competition and ‘Schools on Board' programs.

  18. The International Polar Year (IPY) Circumpolar Flaw Lead (CFL) System Study

    NASA Astrophysics Data System (ADS)

    Barber, D. G.; Papakyriakou, T.; MacDonald, R.; Gratton, Y.; Fortier, L.; Gosselin, M.; Hanesiak, J.; Tremblay, J.; Ferguson, S.; Stern, G.; Meakin, S.; Deming, J.; Leitch, D.

    2008-12-01

    The International Polar Year (IPY) Circumpolar Flaw Lead (CFL) system study supported a large multidisciplinary overwintering in the Banks Island (NT) flaw lead over the period September 2007 to August 2008. The CFL system is formed when the central pack ice (which is mobile) moves away from coastal fast ice, opening a flaw lead. The CFL forms in the fall and continues as thin ice or open water throughout the winter. The flaw lead is circumpolar, with recurrent and interconnected polynyas occurring throughout the Arctic. The overarching objectives of the CFL project were to contrast the physical and biological systems of the flaw lead open water and thin ice to the adjacent landfast ice cover. The Canadian Research Icebreaker (NGCC Amundsen) completed the first-ever overwintering of a research icebreaker in the flaw lead. She supported a total of 11,000 person days distributed across 295 investigators from 28 different countries, making the CFL project the largest single IPY effort in the northern hemisphere. The project obtained many first-ever measurements of a complete suite of physical, biogeochemical, contaminant and marine ecosystem variables across the open water - fast ice contrast. Throughout the project we recognized that Inuvialuit and western science have two different ways of understanding the dramatic changes that are occurring in this sector of the Arctic. This 'two-ways-of-knowing' saw the integration of traditional knowledge studies with the science teams onboard the Amundsen. We present information on the design of the project, an overview of the sampling program completed, highlight the scientific programs conducted, and provide some preliminary results. We conclude with an overview of the various outreach programs including a World Federation of Science Journalists (WFSJ) competition and 'Schools on Board' programs.

  19. Potential change in flaw geometry of an initially shallow finite-length surface flaw during a pressurized-thermal-shock transient

    SciTech Connect

    Shum, D.K.; Bryson, J.W.; Merkle, J.G.

    1993-09-01

    This study presents preliminary estimates on whether an shallow, axially oriented, inner-surface finite-length flaw in a PWR-RPV would tend to elongate in the axial direction and/or deepen into the wall of the vessel during a postulated PTS transient. Analysis results obtained based on the assumptions of (1) linear-elastic material response, and (2) cladding with same toughness as the base metal, indicate that a nearly semicircular flaw would likely propagate in the axial direction followed by propagation into the wall of the vessel. Note that these results correspond to initiation within the lower-shelf fracture toughness temperature range, and that their general validity within the lower-transition temperature range remains to be determined. The sensitivity of the numerical results aid conclusions to the following analysis assumptions are evaluated: (1) reference flaw geometry along the entire crack front and especially within the cladding region; (2) linear-elastic vs elastic-plastic description of material response; and (3) base-material-only vs bimaterial cladding-base vessel-model assumption. The sensitivity evaluation indicates that the analysis results are very sensitive to the above assumptions.

  20. Shape Reconstruction of Three-Dimensional Flaw by the Measurement from the Side of Cylindrical Specimen

    NASA Astrophysics Data System (ADS)

    Yamada, M.; Kitahara, M.

    2004-02-01

    The three-dimensional Born and Kirchhoff inversions are modified to the convenient form for cylindrical structures. Moving the measurement plane along the axis of the cylinder, cross-sectional images are obtained by the modified method. The three-dimensional flaw shape is reconstructed by piling up the cross-sectional images. Cement paste and concrete cylinders with flaw models are prepared and ultrasonic measurements are carried out. The measured wave data are fed into the inversion method and the performance of the shape reconstruction is confirmed.

  1. Imaging flaws in thin metal plates using a magneto-optic device

    NASA Technical Reports Server (NTRS)

    Wincheski, B.; Prabhu, D. R.; Namkung, M.; Birt, E. A.

    1992-01-01

    An account is given of the capabilities of the magnetooptic/eddy-current imager (MEI) apparatus in the case of aging aircraft structure-type flaws in 2024-T3 Al alloy plates. Attention is given to images of cyclically grown fatigue cracks from rivetted joints in fabricated lap-joint structures, electrical discharge machining notches, and corrosion spots. Although conventional eddy-current methods could have been used, the speed and ease of MEI's use in these tests is unmatched by such means. Results are displayed in real time as a test piece is scanned, furnishing easily interpreted flaw images.

  2. Internal Rot Detection with the Use of Low-Frequency Flaw Detector

    NASA Astrophysics Data System (ADS)

    Proskórnicki, Marek; Ligus, Grzegorz

    2014-12-01

    The issue of rot detection in standing timber or stocked wood is very important in forest management. Rot flaw detection used for that purpose is represented by invasive and non-invasive devices. Non-invasive devices are very accurate, but due to the cost and complicated operation they have not been applied on a large scale in forest management. Taking into account the practical needs of foresters a prototype of low-frequency flaw was developed. The principle of its operation is based on the difference in acoustic wave propagation in sound wood and wood with rot.

  3. Metrological evaluation of a flaw detector used in non-destructive testing by ultrasound

    NASA Astrophysics Data System (ADS)

    Mayworm, R. C.; Alvarenga, A. V.; Costa-Felix, R. P. B.

    2016-07-01

    Nondestructive tests are widely used in various sectors of industry, and its main techniques are based on the use of ultrasound. The flaw detector is a device used in ultrasonic testing. In this article, it is studied the influence of the flaw detection settings on the measurement result. It was observed that when the speed of sound and the thickness of the standard block are known, the equipment gives the best results, with a maximum error of 08%. The results show the importance of having a standard block calibrated in order to minimize errors.

  4. Exploring Size.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    1995-01-01

    "Exploring" is a magazine of science, art, and human perception that communicates ideas museum exhibits cannot demonstrate easily by using experiments and activities for the classroom. This issue concentrates on size, examining it from a variety of viewpoints. The focus allows students to investigate and discuss interconnections among apparently…

  5. Inspection technique of latent flaws on fine polished glass substrates using stress-induced light scattering method

    NASA Astrophysics Data System (ADS)

    Sakata, Yoshitaro; Sakai, Kazufumi; Nonaka, Kazuhiro

    2014-05-01

    The fine polishing technique, e.g. Chemical Mechanical Polishing treatment (CMP), is one of the most important techniques in the glass substrate manufacturing. However, mechanical interaction, e.g. friction, occurs between the abrasive and the surface of substrates. Therefore, latent flaws are formed in the surfaces of glass substrates depending on the polishing condition. In the case of the cleaning process of the glass substrate in which the latent flaws existed, latent flaws become obvious because glass surfaces were eaten away by chemical interaction of cleaning liquid. Therefore, latent flaws are the cause of decrease the yield of products. In general, non-destructive inspection techniques, e.g. light scattering method, foreign matter on the surface of glass substrates. Though, it is difficult to detect the latent flaws by these method, because these are closed. The present authors propose a novel inspection technique of latent flaws which occurred by the fine polishing technique, using light scattering method with stress concentration (Stress-Induced Light scattering Method; SILSM). SILSM is possible to classify and separately detect latent flaws and particles on the surfaces. Samples are deformed by the actuator and stress concentrations are occurred around the tip of latent flaws. By photo-elastic effect, the refractive index of around the tip of latent flaws is changed. And then, changed refractive index is detected by cooled CCD camera as the light scattering intensity. In this report, applying SILSM to glass substrates, latent flaws on the surface of glass substrates are detected non-destructively, and the usefulness of SILSM is evaluated as novel inspection technique of latent flaws.

  6. The Tangle of Student Allowances.

    ERIC Educational Resources Information Center

    Thomson, Norman J.

    1980-01-01

    A discussion of the distribution of student financial aid in Australia focuses on these issues: direct vs. indirect payment to students; inequality in living allowances given to secondary and postsecondary students; and distribution of expense allowances by state government and living allowances by the Commonwealth. (MSE)

  7. Experimental constraints on the energy budget of dynamic gouge formation: effects of rock strength, material heterogeneity, and initial flaw characteristics

    NASA Astrophysics Data System (ADS)

    Griffith, Ashley; Barber, Troy; Borjas, Christopher; Ghaffari, Hamed

    2016-04-01

    Fault core materials are characterized by substantial grain size reduction relative to host and damage zone rocks. The properties of these materials control fault strength and frictional behavior, and they record valuable information about rupture and slip processes. At high strain rates and large stress amplitudes characteristic of earthquake rupture tips, rock failure passes through a fragmentation transition from discrete fracture to pulverization; therefore much of the observed grain size reduction at the leading edge of propagating earthquake ruptures. Past examinations of particle size distributions in gouge formed in the cores of natural faults have led to contrasting conclusions that during a single event, the energy associated with creation of new surface area during this grain size reduction can be as large as 50%, or as little as <1% of the earthquake energy budget; however these estimates are difficult to confirm due to (A) challenges associated with accurate particle size measurement and (B) uncertainty regarding the variety of (not-necessarily coseismic) physico-chemical processes that may contribute to the observed grain size reduction. Here we study the micromechanics and energy budget of dynamic rock fragmentation under impulsive compressive loads using a Split Hopkinson Pressure Bar. We present new experimental results on Arkansas Novaculite and Westerly Granite coupled with microstructural observations and BET surface area measurements of post-mortem specimens. We show that the energy partitioned into creation of new surface areas approaches a significant portion of the total dissipated energy during our experiments, but this partitioning can be buffered by the presence of flaws and/or significant material heterogeneity. The results of this work have important implications for lithologic controls on gouge formation and energy partitioning during earthquakes.

  8. Flawed Implementation or Inconsistent Logics? Lessons from Higher Education Reform in Ukraine

    ERIC Educational Resources Information Center

    Shaw, Marta A.

    2013-01-01

    This article investigates two competing explanations of why reforms associated with the Bologna process brought disappointing results in Ukraine. The lack of anticipated benefits from the reforms may stem either from a flawed implementation of the Bologna process, or from more fundamental differences between the models of higher education…

  9. Alpha-Helical Protein Networks Are Self-Protective and Flaw-Tolerant

    PubMed Central

    Ackbarow, Theodor; Sen, Dipanjan; Thaulow, Christian; Buehler, Markus J.

    2009-01-01

    Alpha-helix based protein networks as they appear in intermediate filaments in the cell’s cytoskeleton and the nuclear membrane robustly withstand large deformation of up to several hundred percent strain, despite the presence of structural imperfections or flaws. This performance is not achieved by most synthetic materials, which typically fail at much smaller deformation and show a great sensitivity to the existence of structural flaws. Here we report a series of molecular dynamics simulations with a simple coarse-grained multi-scale model of alpha-helical protein domains, explaining the structural and mechanistic basis for this observed behavior. We find that the characteristic properties of alpha-helix based protein networks are due to the particular nanomechanical properties of their protein constituents, enabling the formation of large dissipative yield regions around structural flaws, effectively protecting the protein network against catastrophic failure. We show that the key for these self protecting properties is a geometric transformation of the crack shape that significantly reduces the stress concentration at corners. Specifically, our analysis demonstrates that the failure strain of alpha-helix based protein networks is insensitive to the presence of structural flaws in the protein network, only marginally affecting their overall strength. Our findings may help to explain the ability of cells to undergo large deformation without catastrophic failure while providing significant mechanical resistance. PMID:19547709

  10. Alpha-helical protein networks are self-protective and flaw-tolerant.

    PubMed

    Ackbarow, Theodor; Sen, Dipanjan; Thaulow, Christian; Buehler, Markus J

    2009-06-23

    Alpha-helix based protein networks as they appear in intermediate filaments in the cell's cytoskeleton and the nuclear membrane robustly withstand large deformation of up to several hundred percent strain, despite the presence of structural imperfections or flaws. This performance is not achieved by most synthetic materials, which typically fail at much smaller deformation and show a great sensitivity to the existence of structural flaws. Here we report a series of molecular dynamics simulations with a simple coarse-grained multi-scale model of alpha-helical protein domains, explaining the structural and mechanistic basis for this observed behavior. We find that the characteristic properties of alpha-helix based protein networks are due to the particular nanomechanical properties of their protein constituents, enabling the formation of large dissipative yield regions around structural flaws, effectively protecting the protein network against catastrophic failure. We show that the key for these self protecting properties is a geometric transformation of the crack shape that significantly reduces the stress concentration at corners. Specifically, our analysis demonstrates that the failure strain of alpha-helix based protein networks is insensitive to the presence of structural flaws in the protein network, only marginally affecting their overall strength. Our findings may help to explain the ability of cells to undergo large deformation without catastrophic failure while providing significant mechanical resistance.

  11. Cracking Process and Stress Field Evolution in Specimen Containing Combined Flaw Under Uniaxial Compression

    NASA Astrophysics Data System (ADS)

    Liu, Ting; Lin, Baiquan; Yang, Wei; Zou, Quanle; Kong, Jia; Yan, Fazhi

    2016-08-01

    Hydraulic slotting, an efficient technique for underground enhanced coal bed methane (ECBM) recovery, has been widely used in China. However, its pressure relief mechanism is unclear. Thus far, only limited research has been conducted on the relationships among the mechanical properties, flaw parameters, and crack propagation patterns of coal after hydraulic slotting. In addition, because of the limitations of test methods, an in-depth information is not available for this purpose. In this work, numerical models of specimens containing combined flaws are established based on particle flow code method. Our results provide insights into the effects of flaw inclination angle on the mechanical properties, crack propagation patterns, and temporal and spatial evolution rules of stress field in specimens containing combined flaws during the loading process. Besides, based on the initiation position and underlying mechanism, three types of crack initiation modes are identified from the failure processes of specimens. Finally, the crack propagation pattern is quantitatively described by the fractal dimension, which is found to be inversely proportional to the uniaxial compressive strength and elastic modulus of the specimen. To verify the rationality of the numerical simulation results, laboratory tests were conducted and their results match well with those obtained from the numerical simulation.

  12. The Dangerous Myth of Emerging Adulthood: An Evidence-Based Critique of a Flawed Developmental Theory

    ERIC Educational Resources Information Center

    Côté, James E.

    2014-01-01

    This article examines the theory of emerging adulthood, introduced into the literature by Arnett (2000), in terms of its methodological and evidential basis, and finds it to be unsubstantiated on numerous grounds. Other, more convincing, formulations of variations in the transition to adulthood are examined. Most flawed academic theories are…

  13. Apparatus and method for detecting and/or measuring flaws in conductive material

    DOEpatents

    Hockey, Ronald L.; Riechers, Douglas M.

    2000-01-01

    The present invention uses a magnet and sensor coil unilaterial and in relative motion to a conductive material, to measure perturbation or variation in the magnetic field in the presence of a flaw. A liftoff compensator measures a distance between the conductive material and the magnet.

  14. Surface flaw reliability analysis of ceramic components with the SCARE finite element postprocessor program

    NASA Technical Reports Server (NTRS)

    Gyekenyesi, John P.; Nemeth, Noel N.

    1987-01-01

    The SCARE (Structural Ceramics Analysis and Reliability Evaluation) computer program on statistical fast fracture reliability analysis with quadratic elements for volume distributed imperfections is enhanced to include the use of linear finite elements and the capability of designing against concurrent surface flaw induced ceramic component failure. The SCARE code is presently coupled as a postprocessor to the MSC/NASTRAN general purpose, finite element analysis program. The improved version now includes the Weibull and Batdorf statistical failure theories for both surface and volume flaw based reliability analysis. The program uses the two-parameter Weibull fracture strength cumulative failure probability distribution model with the principle of independent action for poly-axial stress states, and Batdorf's shear-sensitive as well as shear-insensitive statistical theories. The shear-sensitive surface crack configurations include the Griffith crack and Griffith notch geometries, using the total critical coplanar strain energy release rate criterion to predict mixed-mode fracture. Weibull material parameters based on both surface and volume flaw induced fracture can also be calculated from modulus of rupture bar tests, using the least squares method with known specimen geometry and grouped fracture data. The statistical fast fracture theories for surface flaw induced failure, along with selected input and output formats and options, are summarized. An example problem to demonstrate various features of the program is included.

  15. Anisotropic determination and correction for ultrasonic flaw detection by spectral analysis

    DOEpatents

    Adler, Laszlo; Von Cook, K.; Simpson, Jr., William A.; Lewis, D. Kent

    1978-01-01

    The anisotropic nature of a material is determined by measuring the velocity of an ultrasonic longitudinal wave and a pair of perpendicular ultrasonic shear waves through a sample of the material each at a plurality of different angles in three planes orthogonal to each other. The determined anisotropic nature is used as a correction factor in a spectral analyzing system of flaw determination.

  16. Fiber Optic Thermographic Detection of Flaws in Composites

    NASA Technical Reports Server (NTRS)

    Wu, Meng-Chou; Winfree, William P.

    2009-01-01

    Optical fibers with multiple Bragg gratings bonded to surfaces of structures were used for thermographic detection of subsurface defects in structures. The investigated structures included a 10-ply composite specimen with subsurface delaminations of various sizes and depths. Both during and following the application of a thermal heat flux to the surface, the individual Bragg grating sensors measured the temporal and spatial temperature variations. The obtained data were analyzed with thermal modeling to reveal particular characteristics of the interested areas. These results were found to be consistent with the simulation results.

  17. Effects of proof loads and combined mode loadings on fracture and flaw growth characteristics of aerospace alloys

    NASA Technical Reports Server (NTRS)

    Shah, R. C.

    1974-01-01

    This experimental program was undertaken to determine the effects of (1) combined tensile and bending loadings, (2) combined tensile and shear loadings, and (3) proof overloads on fracture and flaw growth characteristics of aerospace alloys. Tests were performed on four alloys: 2219-T87 aluminum, 5Al-2.5Sn (ELl) titanium, 6Al-4V beta STA titanium and high strength 4340 steel. Tests were conducted in room air, gaseous nitrogen at -200F (144K), liquid nitrogen and liquid hydrogen. Flat center cracked and surface flawed specimens, cracked tube specimens, circumferentially notched round bar and surface flawed cylindrical specimens were tested. The three-dimensional photoelastic technique of stress freezing and slicing was used to determine stress intensity factors for surface flawed cylindrical specimens subjected to tension or torsion. Results showed that proof load/temperature histories used in the tests have a small beneficial effect or no effect on subsequent fracture strength and flaw growth rates.

  18. Stress-induced light scattering method for the detection of latent flaws on fine polished glass substrates.

    PubMed

    Sakata, Y; Sakai, K; Nonaka, K

    2014-08-01

    Fine polishing techniques, such as the chemical mechanical polishing treatment, are one of the most important technique to glass substrate manufacturing. Mechanical interaction in the form of friction occurs between the abrasive and the substrate surface during polishing, which may cause formation of latent flaws on the glass substrate surface. Fine polishing-induced latent flaws may become obvious during a subsequent cleaning process if glass surfaces are corroded away by chemical interaction with the cleaning liquid. Latent flaws thus reduce product yield. In general, non-destructive inspection techniques, such as the light-scattering methods, used to detect foreign matters on the glass substrate surface. However, it is difficult to detect latent flaws by these methods because the flaws remain closed. Authors propose a novel inspection technique for fine polishing-induced latent flaws by combining the light scattering method with stress effects, referred to as the stress-induced light scattering method (SILSM). SILSM is able to distinguish between latent flaws and particles on the surface. In this method, samples are deformed by an actuator and stress effects are induced around the tips of latent flaws. Due to the photoelastic effect, the refractive index of the material around the tip of a latent flaw is changed. This changed refractive index is in turn detected by a cooled charge-coupled device camera as variations in light scattering intensity. In this report, surface latent flaws are detected non-destructively by applying SILSM to glass substrates, and the utility of SILSM evaluated as a novel inspection technique.

  19. Stress-induced light scattering method for the detection of latent flaws on fine polished glass substrates

    NASA Astrophysics Data System (ADS)

    Sakata, Y.; Sakai, K.; Nonaka, K.

    2014-08-01

    Fine polishing techniques, such as the chemical mechanical polishing treatment, are one of the most important technique to glass substrate manufacturing. Mechanical interaction in the form of friction occurs between the abrasive and the substrate surface during polishing, which may cause formation of latent flaws on the glass substrate surface. Fine polishing-induced latent flaws may become obvious during a subsequent cleaning process if glass surfaces are corroded away by chemical interaction with the cleaning liquid. Latent flaws thus reduce product yield. In general, non-destructive inspection techniques, such as the light-scattering methods, used to detect foreign matters on the glass substrate surface. However, it is difficult to detect latent flaws by these methods because the flaws remain closed. Authors propose a novel inspection technique for fine polishing-induced latent flaws by combining the light scattering method with stress effects, referred to as the stress-induced light scattering method (SILSM). SILSM is able to distinguish between latent flaws and particles on the surface. In this method, samples are deformed by an actuator and stress effects are induced around the tips of latent flaws. Due to the photoelastic effect, the refractive index of the material around the tip of a latent flaw is changed. This changed refractive index is in turn detected by a cooled charge-coupled device camera as variations in light scattering intensity. In this report, surface latent flaws are detected non-destructively by applying SILSM to glass substrates, and the utility of SILSM evaluated as a novel inspection technique.

  20. Development of Natural Flaw Samples for Evaluating Nondestructive Testing Methods for Foam Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Davis, Jason; Farrington, Seth; Walker, James

    2007-01-01

    Low density polyurethane foam has been an important insulation material for space launch vehicles for several decades. The potential for damage from foam breaking away from the NASA External Tank was not realized until the foam impacts on the Columbia Orbiter vehicle caused damage to its Leading Edge thermal protection systems (TPS). Development of improved inspection techniques on the foam TPS is necessary to prevent similar occurrences in the future. Foamed panels with drilled holes for volumetric flaws and Teflon inserts to simulate debonded conditions have been used to evaluate and calibrate nondestructive testing (NDT) methods. Unfortunately the symmetric edges and dissimilar materials used in the preparation of these simulated flaws provide an artificially large signal while very little signal is generated from the actual defects themselves. In other words, the same signal are not generated from the artificial defects in the foam test panels as produced when inspecting natural defect in the ET foam TPS. A project to create more realistic voids similar to what actually occurs during manufacturing operations was began in order to improve detection of critical voids during inspections. This presentation describes approaches taken to create more natural voids in foam TPS in order to provide a more realistic evaluation of what the NDT methods can detect. These flaw creation techniques were developed with both sprayed foam and poured foam used for insulation on the External Tank. Test panels with simulated defects have been used to evaluate NDT methods for the inspection of the External Tank. A comparison of images between natural flaws and machined flaws generated from backscatter x-ray radiography, x-ray laminography, terahertz imaging and millimeter wave imaging show significant differences in identifying defect regions.

  1. Effect of Combined Loading Due to Bending and Internal Pressure on Pipe Flaw Evaluation Criteria

    NASA Astrophysics Data System (ADS)

    Miura, Naoki; Sakai, Shinsuke

    Considering a rule for the rationalization of maintenance of Light Water Reactor piping, reliable flaw evaluation criteria are essential for determining how a detected flaw will be detrimental to continuous plant operation. Ductile fracture is one of the dominant failure modes that must be considered for carbon steel piping and can be analyzed by elastic-plastic fracture mechanics. Some analytical efforts have provided various flaw evaluation criteria using load correction factors, such as the Z-factors in the JSME codes on fitness-for-service for nuclear power plants and the section XI of the ASME boiler and pressure vessel code. The present Z-factors were conventionally determined, taking conservativity and simplicity into account; however, the effect of internal pressure, which is an important factor under actual plant conditions, was not adequately considered. Recently, a J-estimation scheme, LBB.ENGC for the ductile fracture analysis of circumferentially through-wall-cracked pipes subjected to combined loading was developed for more accurate prediction under more realistic conditions. This method explicitly incorporates the contributions of both bending and tension due to internal pressure by means of a scheme that is compatible with an arbitrary combined-loading history. In this study, the effect of internal pressure on the flaw evaluation criteria was investigated using the new J-estimation scheme. The Z-factor obtained in this study was compared with the presently used Z-factors, and the predictability of the current flaw evaluation criteria was quantitatively evaluated in consideration of the internal pressure.

  2. 40 CFR 35.2025 - Allowance and advance of allowance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... facilities planning and design of the project and Step 7 agreements will include an allowance for facility... grant applicants for facilities planning and project design. (2) The State may request that the right...

  3. 40 CFR 35.2025 - Allowance and advance of allowance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... facilities planning and design of the project and Step 7 agreements will include an allowance for facility... grant applicants for facilities planning and project design. (2) The State may request that the right...

  4. 40 CFR 35.2025 - Allowance and advance of allowance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... facilities planning and design of the project and Step 7 agreements will include an allowance for facility... grant applicants for facilities planning and project design. (2) The State may request that the right...

  5. 40 CFR 35.2025 - Allowance and advance of allowance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... facilities planning and design of the project and Step 7 agreements will include an allowance for facility... grant applicants for facilities planning and project design. (2) The State may request that the right...

  6. 76 FR 70883 - Clothing Allowance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-16

    ... published in the Federal Register on February 2, 2011 (76 FR 5733-5734), VA proposed to amend its... appliances affecting different articles of clothing. 76 FR 5733; Sursely, 551 F.3d at 1356. VA will make the... allowances. The amendment provides for an annual clothing allowance for each qualifying prosthetic...

  7. Detection of flaws on surface of civil infrastructures and their profiling using imaging system with laser displacement sensor

    NASA Astrophysics Data System (ADS)

    Giri, Paritosh; Kharkovsky, Sergey

    2016-04-01

    Civil infrastructures such as buildings, bridges, roads and pipelines are the integral part of people's lives and their failure can have large public safety and economic consequences. Early detection of flaws in civil infrastructures and their appropriate retrofitting will aid in preventing this failure. Flaws such as cracks and impact damages initially occur on the surface and propagate inside the materials causing further degradation. There is a need to develop systems that can detect these surface flaws. Developing a system with one sensing technique which can detect the flaws is a challenging task since infrastructures are made up of diverse materials such as concrete, metal, plastics, composite and timber that have different electrical and mechanical properties. It is also desired that non-plain surfaces with complex profiles can be interrogated and surface flaws can be detected. We have proposed an imaging system capable of interrogating structures with complex surface profiles for the purpose of detection and evaluation of surface flaws such as cracks and impact damages using laser displacement sensor (LDS). The developed system consists of LDS mounted on the scanner which is able to perform raster scan over the specimen under test. The reading of displacement from the sensor head to the laser spot on the surface of the test material is then used to generate images which can be used to detect the surface flaws. The proof of concept is given by testing specimens made of metal, concrete and plastics with complex surface profiles.

  8. Origin of light scattering variations of a latent flaw through light scattering measurement with applied stress effect

    NASA Astrophysics Data System (ADS)

    Sakata, Yoshitaro; Terasaki, Nao; Sakai, Kazufumi; Nonaka, Kazuhiro

    2016-11-01

    The stress-induced light scattering method (SILSM) was proposed for inspecting surface to detect polishing induced latent flaws. In this study, in order to clarify the mechanism of the light scattering intensity variation of latent flaws using SILSM, we have investigated stress effect of light scattering intensities using polarized light system and calculated the reflectance and the retardation using Jones matrix. As the results, we evaluated the change in the birefringence around a tip of a latent flaw between before and after stress were applied.

  9. The effect of initial flaw configuration on leak critical pressure vessel design

    NASA Technical Reports Server (NTRS)

    Pettit, D. E.; Hoeppner, D. W.

    1975-01-01

    The effect of initial flaw shape and depth on the cycles required to produce a pressure leak condition in parent and welded 2219-T87 aluminum was examined for thicknesses from 0.04 to 0.3 inch. Initial flaw aspect ratios of 0.5, 0.3, and 0.15 were examined for tests conducted at a frequency of 4 Hz at room temperature and at 300 F. A computer program developed by Forman was used to predict the cycles to leak curve as a function of initial crack aspect ratio, material thickness, and specimen type and the results compared with the experimental data. Sources of error in the crack propagation analysis and the interface with NDI capabilities are discussed.

  10. Investigation of flaw geometry and loading effects on plane strain fracture in metallic structures

    NASA Technical Reports Server (NTRS)

    Hall, L. R.; Finger, R. W.

    1971-01-01

    The effects on fracture and flaw growth of weld-induced residual stresses, combined bending and tension stresses, and stress fields adjacent to circular holes in 2219-T87 aluminum and 5AI-2.5Sn(ELI) titanium alloys were evaluated. Static fracture tests were conducted in liquid nitrogen; fatigue tests were performed in room air, liquid nitrogen, and liquid hydrogen. Evaluation of results was based on linear elastic fracture mechanics concepts and was directed to improving existing methods of estimating minimum fracture strength and fatigue lives for pressurized structure in spacecraft and booster systems. Effects of specimen design in plane-strain fracture toughness testing were investigated. Four different specimen types were tested in room air, liquid nitrogen and liquid hydrogen environments using the aluminum and titanium alloys. Interferometry and holograph were used to measure crack-opening displacements in surface-flawed plexiglass test specimens. Comparisons were made between stress intensities calculated using displacement measurements, and approximate analytical solutions.

  11. Method and apparatus for detecting flaws and defects in heat seals

    NASA Technical Reports Server (NTRS)

    Rai, Kula R. (Inventor); Lew, Thomas M. (Inventor); Sinclair, Robert B. (Inventor)

    1993-01-01

    Flaws and defects in heat seals formed between sheets of translucent film are identified by optically examining consecutive lateral sections of the seal along the seal length. Each lateral seal section is illuminated and an optical sensor array detects the intensity of light transmitted through the seal section for the purpose of detecting and locating edges in the heat seal. A line profile for each consecutive seal section is derived having an amplitude proportional to the change in light intensity across the seal section. Instances in the derived line profile where the amplitude is greater than a threshold level indicate the detection of a seal edge. The detected edges in each derived line profile are then compared to a preset profile edge standard to identify the existence of a flaw or defect.

  12. Flaw Stability Considering Residual Stress for Aging Management of Spent Nuclear Fuel Multiple-Purpose Canisters

    DOE PAGES

    Lam, Poh-Sang; Sindelar, Robert L.

    2016-04-28

    A typical multipurpose canister (MPC) is made of austenitic stainless steel and is loaded with spent nuclear fuel assemblies. Because heat treatment for stress relief is not required for the construction of the MPC, the canister is susceptible to stress corrosion cracking in the weld or heat affected zone regions under long-term storage conditions. Logic for flaw acceptance is developed should crack-like flaws be detected by Inservice Inspection. The procedure recommended by API 579-1/ASME FFS-1, Fitness-for-Service, is used to calculate the instability crack length or depth by failure assessment diagram. It is demonstrated that the welding residual stress has amore » strong influence on the results.« less

  13. Self-Nulling Eddy Current Probe for Surface and Subsurface Flaw Detection

    NASA Technical Reports Server (NTRS)

    Wincheski, B.; Fulton, J. P.; Nath, S.; Namkung, M.; Simpson, J. W.

    1994-01-01

    An eddy current probe which provides a null-signal in the presence of unflawed material without the need for any balancing circuitry has been developed at NASA Langley Research Center. Such a unique capability of the probe reduces set-up time, eliminates tester configuration errors, and decreases instrumentation requirements. The probe is highly sensitive to surface breaking fatigue cracks, and shows excellent resolution for the measurement of material thickness, including material loss due to corrosion damage. The presence of flaws in the material under test causes an increase in the extremely stable and reproducible output voltage of the probe. The design of the probe and some examples illustrating its flaw detection capabilities are presented.

  14. Radially Focused Eddy Current Sensor for Detection of Longitudinal Flaws in Metallic Tubes

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A. (Inventor); Simpson, John W. (Inventor); Fulton, James P. (Inventor); Nath, Shridhar C. (Inventor); Todhunter, Ronald G. (Inventor); Namkung, Min (Inventor)

    1999-01-01

    A radially focused eddy current sensor detects longitudinal flaws in a metal tube. A drive coil induces eddy currents within the wall of the metal tube. A pick-up cod is spaced apart from the drive coil along the length of the metal tube. The pick@up coil is positioned with one end thereof lying adjacent the wall of the metal tube such that the pick-up coil's longitudinal axis is perpendicular to the wall of the metal tube. To isolate the pick-up coil from the magnetic flux of the drive coil and the flux from the induced eddy currents. except the eddy currents diverted by a longitudinal flaw. an electrically conducting material high in magnetic permeability surrounds all of the pick-up coil except its one end that is adjacent the walls of the metal tube. The electrically conducting material can extend into and through the drive coil in a coaxial relationship therewith.

  15. Signal Processing Variables for Optimization of Flaw Detection in Composites Using Ultrasonic Guided Wave Scanning

    NASA Technical Reports Server (NTRS)

    Roth, Don J.; Cosgriff, Laura M.; Martin, Richard E.; Teemer, LeTarrie

    2004-01-01

    This study analyzes the effect of signal processing variables on the ability of the ultrasonic guided wave scan method at NASA Glenn Research Center to distinguish various flaw conditions in ceramic matrix composites samples. In the ultrasonic guided wave scan method, several time- and frequency-domain parameters are calculated from the ultrasonic guided wave signal at each scan location to form images. The parameters include power spectral density, centroid mean time, total energy (zeroth moment), centroid frequency, and ultrasonic decay rate. A number of signal processing variables are available to the user when calculating these parameters. These signal processing variables include 1) the time portion of the time-domain waveform processed, 2) integration type for the properties requiring integrations, 3) bounded versus unbounded integrations, 4) power spectral density window type, 5) and the number of time segments chosen if using the short-time fourier transform to calculate ultrasonic decay rate. Flaw conditions examined included delamination, cracking, and density variation.

  16. Cyclic Fatigue of Brittle Materials with an Indentation-Induced Flaw System

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Salem, Jonathan A.

    1996-01-01

    The ratio of static to cyclic fatigue life, or 'h ratio', was obtained numerically for an indentation flaw system subjected to sinusoidal loading conditions. Emphasis was placed on developing a simple, quick lifetime prediction tool. The solution for the h ratio was compared with experimental static and cyclic fatigue data obtained from as-indented 96 wt.% alumina specimens tested in room-temperature distilled water.

  17. Detection and characterization of flaws in segments of light water reactor pressure vessels

    SciTech Connect

    Cook, K.V.; Cunningham, R.A. Jr.; McClung, R.W.

    1987-01-01

    Studies have been conducted to determine flaw density in segments cut from light water reactor (LWR) pressure vessels as part of the Oak Ridge National Laboratory's Heavy-Section Steel Technology (HSST) Program. Segments from the Hope Creek Unit 2 vessil and the Pilgrim Unit 2 Vessel were purchased from salvage dealers. Hope Creek was a boiling water reactor (BWR) design and Pilgrim was a pressurized water reactor (PWR) design. Neither were ever placed in service. Objectives were to evaluate these LWR segments for flaws with ultrasonic and liquid penetrant techniques. Both objectives were successfully completed. One significant indication was detected in a Hope Creek seam weld by ultrasonic techniques and characterized by further analyses terminating with destructive correlation. This indication (with a through-wall dimension of approx.6 mm (approx.0.24 in.)) was detected in only 3 m (10 ft) of weldment and offers extremely limited data when compared to the extent of welding even in a single pressure vessel. However, the detection and confirmation of the flaw in the arbitrarily selected sections implies the Marshall report estimates (and others) are nonconservative for such small flaws. No significant indications were detected in the Pilgrim material by ultrasonic techniques. Unfortunately, the Pilgrim segments contained relatively little weldment; thus, we limited our ultrasonic examinations to the cladding and subcladding regions. Fluorescent liquid penetrant inspection of the cladding surfaces for both LWR segments detected no significant indications (i.e., for a total of approximately 6.8 m/sup 2/ (72 ft/sup 2/) of cladding surface).

  18. Application and assessment of ultrasonic inspection methods for flaw detection and characterization of manganese steel frogs

    NASA Astrophysics Data System (ADS)

    Cinson, A.; Diaz, A.; Prowant, M.

    2011-04-01

    Ultrasonic nondestructive examination (NDE) has a long and successful history of application across a wide array of industries, including nuclear, aerospace, and transportation sectors. In coarse-grained, cast Manganese (Mn) steel frog components, NDE/inspection challenges are encountered both in-field (after the frogs have been installed on a rail line) and at the manufacturing facilities during post-fabrication QA/QC activities. Periodically inherently flawed frogs are received from a manufacturer, and put into service, as most railroad operators do not have a means to conduct pre-service examinations on received components. Accordingly, there is a need for a pre-service inspection system that can provide a rapid, cost-effective and non-intrusive inspection capability for detection of defects, flaws, and other anomalies in frog components, in order to avoid premature initiation of cracks or failures of these components during service. This study focused on evaluating use of a volumetric phased-array ultrasonic testing (PA-UT) method to monitor fabrication quality assurance. In this preliminary assessment of using PA-UT, data were acquired at a frequency of 2.0 MHz on a known, flawed Mn steel frog component directly from a manufacturing facility. The component contained flaws commonly found as a result of the manufacturing process of these cast rail components. The data were analyzed and the anomalies were detected, localized and characterized. Results were compared against baseline radiographic data. A detection metric was reported in the form of signal-to-noise values.

  19. Improved multi-directional eddy current inspection test apparatus for detecting flaws in metal articles

    DOEpatents

    Nance, Roy A.; Hartley, William H.; Caffarel, Alfred J.

    1984-01-01

    Apparatus is described for detecting flaws in a tubular workpiece in a single scan. The coils of a dual coil bobbin eddy current inspection probe are wound at a 45.degree. angle to the transverse axis of the probe, one coil having an angular position about the axis about 90.degree. relative to the angular position of the other coil, and the angle of intersection of the planes containing the coils being about 60.degree..

  20. Signal detection and noise suppression using a wavelet transform signal processor: application to ultrasonic flaw detection.

    PubMed

    Abbate, A; Koay, J; Frankel, J; Schroeder, S C; Das, P

    1997-01-01

    The utilization of signal processing techniques in nondestructive testing, especially in ultrasonics, is widespread. Signal averaging, matched filtering, frequency spectrum analysis, neural nets, and autoregressive analysis have all been used to analyze ultrasonic signals. The Wavelet Transform (WT) is the most recent technique for processing signals with time-varying spectra. Interest in wavelets and their potential applications has resulted in an explosion of papers; some have called the wavelets the most significant mathematical event of the past decade. In this work, the Wavelet Transform is utilized to improve ultrasonic flaw detection in noisy signals as an alternative to the Split-Spectrum Processing (SSP) technique. In SSP, the frequency spectrum of the signal is split using overlapping Gaussian passband filters with different central frequencies and fixed absolute bandwidth. A similar approach is utilized in the WT, but in this case the relative bandwidth is constant, resulting in a filter bank with a self-adjusting window structure that can display the temporal variation of the signal's spectral components with varying resolutions. This property of the WT is extremely useful for detecting flaw echoes embedded in background noise. The detection of ultrasonic pulses using the wavelet transform is described and numerical results show good detection even for signal-to-noise ratios (SNR) of -15 dB. The improvement in detection was experimentally verified using steel samples with simulated flaws.

  1. Flaw-induced plastic-flow dynamics in bulk metallic glasses under tension

    PubMed Central

    Chen, S. H.; Yue, T. M.; Tsui, C. P.; Chan, K. C.

    2016-01-01

    Inheriting amorphous atomic structures without crystalline lattices, bulk metallic glasses (BMGs) are known to have superior mechanical properties, such as high strength approaching the ideal value, but are susceptible to catastrophic failures. Understanding the plastic-flow dynamics of BMGs is important for achieving stable plastic flow in order to avoid catastrophic failures, especially under tension, where almost all BMGs demonstrate limited plastic flow with catastrophic failure. Previous findings have shown that the plastic flow of BMGs displays critical dynamics under compression tests, however, the plastic-flow dynamics under tension are still unknown. Here we report that power-law critical dynamics can also be achieved in the plastic flow of tensile BMGs by introducing flaws. Differing from the plastic flow under compression, the flaw-induced plastic flow under tension shows an upward trend in the amplitudes of the load drops with time, resulting in a stable plastic-flow stage with a power-law distribution of the load drop. We found that the flaw-induced plastic flow resulted from the stress gradients around the notch roots, and the stable plastic-flow stage increased with the increase of the stress concentration factor ahead of the notch root. The findings are potentially useful for predicting and avoiding the catastrophic failures in tensile BMGs by tailoring the complex stress fields in practical structural-applications. PMID:27779221

  2. On self-propagating methodological flaws in performance normalization for strength and power sports.

    PubMed

    Arandjelović, Ognjen

    2013-06-01

    Performance in strength and power sports is greatly affected by a variety of anthropometric factors. The goal of performance normalization is to factor out the effects of confounding factors and compute a canonical (normalized) performance measure from the observed absolute performance. Performance normalization is applied in the ranking of elite athletes, as well as in the early stages of youth talent selection. Consequently, it is crucial that the process is principled and fair. The corpus of previous work on this topic, which is significant, is uniform in the methodology adopted. Performance normalization is universally reduced to a regression task: the collected performance data are used to fit a regression function that is then used to scale future performances. The present article demonstrates that this approach is fundamentally flawed. It inherently creates a bias that unfairly penalizes athletes with certain allometric characteristics, and, by virtue of its adoption in the ranking and selection of elite athletes, propagates and strengthens this bias over time. The main flaws are shown to originate in the criteria for selecting the data used for regression, as well as in the manner in which the regression model is applied in normalization. This analysis brings into light the aforesaid methodological flaws and motivates further work on the development of principled methods, the foundations of which are also laid out in this work.

  3. Stress analysis and damage evaluation of flawed composite laminates by hybrid-numerical methods

    NASA Technical Reports Server (NTRS)

    Yang, Yii-Ching

    1992-01-01

    Structural components in flight vehicles is often inherited flaws, such as microcracks, voids, holes, and delamination. These defects will degrade structures the same as that due to damages in service, such as impact, corrosion, and erosion. It is very important to know how a structural component can be useful and survive after these flaws and damages. To understand the behavior and limitation of these structural components researchers usually do experimental tests or theoretical analyses on structures with simulated flaws. However, neither approach has been completely successful. As Durelli states that 'Seldom does one method give a complete solution, with the most efficiency'. Examples of this principle is seen in photomechanics which additional strain-gage testing can only average stresses at locations of high concentration. On the other hand, theoretical analyses including numerical analyses are implemented with simplified assumptions which may not reflect actual boundary conditions. Hybrid-Numerical methods which combine photomechanics and numerical analysis have been used to correct this inefficiency since 1950's. But its application is limited until 1970's when modern computer codes became available. In recent years, researchers have enhanced the data obtained from photoelasticity, laser speckle, holography and moire' interferometry for input of finite element analysis on metals. Nevertheless, there is only few of literature being done on composite laminates. Therefore, this research is dedicated to this highly anisotropic material.

  4. Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station

    SciTech Connect

    Anderson, Michael T.; Diaz, Aaron A.; Doctor, Steven R.

    2012-06-01

    During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference.

  5. Cracking and Stress-Strain Behavior of Rock-Like Material Containing Two Flaws Under Uniaxial Compression

    NASA Astrophysics Data System (ADS)

    Zhao, Yanlin; Zhang, Lianyang; Wang, Weijun; Pu, Chengzhi; Wan, Wen; Tang, Jingzhou

    2016-07-01

    This paper investigates the cracking and stress-strain behavior, especially the local strain concentration near the flaw tips, of rock-like material containing two flaws. A series of uniaxial compression tests were carried out on rock-like specimens containing two flaws, with strain gauges mounted near the flaw tips to measure the local strain concentration under the uniaxial compressive loading. Four different types of cracks (wing cracks, anti-wing cracks, coplanar shear cracks and oblique shear cracks) and seven patterns of crack coalescences (T1 and T2; S1 and S2; and TS1, TS2 and TS3) are observed in the experiments. The type of crack coalescence is related to the geometry of the flaws. In general, the crack coalescence varies from the S-mode to the TS-mode and then to the T-mode with the increase of the rock bridge ligament angle. The stress-strain curves of the specimens containing two flaws are closely related to the crack development and coalescence process. The strain measurements indicate that the local tensile strain concentration below or above the pre-existing flaw tip causes wing or anti-wing cracks, while the local compressive strain concentration near the flaw tip is related to the shear crack. The measured local tensile strain shows a jump at the initiation of wing- and anti-wing cracks, reflecting the instant opening of the wing- and anti-wing crack propagating through the strain gauge. During the propagation of wing- and anti-wing cracks, the measured local tensile strain gradually increases with few jumps, implying that the opening deformation of wing- and anti-wing cracks occurs in a stable manner. The shear cracks initiate followed by a large and abrupt compressive strain jump and then quickly propagate in an unstable manner resulting in the failure of specimens.

  6. 7 CFR 52.810 - Allowances for quality factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Allowances for quality factors. 52.810 Section 52.810... for Quality Factors § 52.810 Allowances for quality factors. Table I—Allowances for Quality Factors Factor Sample unit size Maximum number permissible for the respective grade A B C Color: Vary markedly...

  7. Electromagnetic methods for measuring materials properties of cylindrical rods and array probes for rapid flaw inspection

    SciTech Connect

    Sun, Haiyan

    2005-01-01

    field in the presence of a finite a two-layer rod and a conductive tube. The results are in very good agreement with those obtained by using a 2D finite element code. In the third part, a new probe technology with enhanced flaw detection capability is described. The new probe can reduce inspection time through the use of multiple Hall sensors. A prototype Hall array probe has been built and tested with eight individual Hall sensor ICs and a racetrack coil. Electronic hardware was developed to interface the probes to an oscilloscope or an eddy current instrument. To achieve high spatial resolution and to limit the overall probe size, high-sensitivity Hall sensor arrays were fabricated directly on a wafer using photolithographic techniques and then mounted in their unencapsulated form. The electronic hardware was then updated to interface the new probes to a laptop computer.

  8. Radial phase variation computing: a tool to improve flaw detection in optical diagnosis by shearographic images.

    PubMed

    Fantin, Analucia V; Willemann, Daniel P; Viotti, Matias R; Albertazzi, Armando

    2013-08-01

    Shearography is an optical and nondestructive technique that has been largely used for damage detection in layered composite materials where delaminations and debondings are found to be among the most common flaws. Shearography detects derivative of the displacements. It is a relative measurement in which two images are recorded for different loading conditions of the sample. The applied loading induces some deformations into the sample, generating a displacement field on its surface. Thermal, acoustical, or mechanical loading are typical excitations applied in a static or dynamic way. The absolute difference between two phase maps recorded at two different loading instances produces an interference fringe pattern, which is directly correlated to the displacements produced on the material surface. In some cases, depending on the loading level and mainly on the sample geometry, interference patterns will contain fringes resulting from geometry changes. This will mask those fringes correlated to flaws introduced into the material, resulting in an image misinterpretation. This phenomenon takes place mainly when the sample has curved geometries, as in, for example, pipe or vessel surfaces. This paper presents an algorithm that uses a mathematical process to improve the visualization of flaws in shearographic images. The mathematical process is based on the calculation of the phase variation, and it is used to search for local deformations contained in the image. This algorithm highlights defect regions and eliminates fringes caused by geometry changes, providing an easier interpretation for complex shearographic images. This paper also shows the principle and the algorithm used for the process. Results, advantages, and difficulties of the method are presented and discussed by using simulated fringe maps as well as real ones. PMID:23913066

  9. Flaw criticality of circular disbond defects in compressive laminates. M.S. Thesis. Interim Report, 1980 - 1981; [graphite-epoxy laminates

    NASA Technical Reports Server (NTRS)

    Webster, J. D.

    1981-01-01

    The compressive behavior of T300/5208 graphite-epoxy laminates containing circular delaminations was studied to determine the flaw criticality of two types of implanted defect, Kapton bag and Teflon film, on several laminate configurations. Defect size was varied. Results, presented in the form of residual strength curves, indicate that the Teflon film defect reduced strength more than the Kapton bad defect in 12-ply samples, but that two laminates (+ or - 45) sub 2s and (90/+ or - 45) sub s were insensitive to any implanted defect. A clear thickness effect was shown to exist for the (o/+ pr 45) sub ns laminate and was attributed to failure mode transition. The analytically predicted buckling loads show excellent agreement with experimental results and are useful in predicting failure mode transition.

  10. Friction Stir Weld Restart+Reweld Repair Allowables

    NASA Technical Reports Server (NTRS)

    Clifton, Andrew

    2008-01-01

    A friction stir weld (FSW) repair method has been developed and successfully implemented on Al 2195 plate material for the Space Shuttle External Fuel Tank (ET). The method includes restarting the friction stir weld in the termination hole of the original weld followed by two reweld passes. Room temperature and cryogenic temperature mechanical properties exceeded minimum FSW design strength and compared well with the development data. Simulated service test results also compared closely to historical data for initial FSW, confirming no change to the critical flaw size or inspection requirements for the repaired weld. Testing of VPPA fusion/FSW intersection weld specimens exhibited acceptable strength and exceeded the minimum design value. Porosity, when present at the intersection was on the root side toe of the fusion weld, the "worst case" being 0.7 inch long. While such porosity may be removed by sanding, this "worst case" porosity condition was tested "as is" and demonstrated that porosity did not negatively affect the strength of the intersection weld. Large, 15-inch "wide panels" FSW repair welds were tested to demonstrate strength and evaluate residual stresses using photo stress analysis. All results exceeded design minimums, and photo stress analysis showed no significant stress gradients due to the presence of the restart and multi-pass FSW repair weld.

  11. The International Polar Year (IPY) Circumpolar Flaw Lead (CFL) system study: a focus on fast ice edge systems

    NASA Astrophysics Data System (ADS)

    Barber, D. G.; Mundy, C. J.; Papakyriakou, T. N.; MacDonald, R. W.; Gratton, Y.; Fortier, L.; Gosselin, M.; Hanesiak, J.; Tremblay, J.; Ferguson, S.; Stern, G.; Meakin, S.; Deming, J. W.; Leitch, D.

    2009-12-01

    The Circumpolar Flaw Lead (CFL) system study supported a large multidisciplinary overwintering in the Banks Island (NT) flaw lead over the period September 2007 to August 2008 as part of the International Polar Year (IPY). The CFL system is formed when the central pack ice (which is mobile) moves away from coastal fast ice, opening a flaw lead. The CFL forms in the fall and continues as thin ice or open water throughout the winter. The flaw lead is circumpolar, with recurrent and interconnected polynyas occurring throughout the Arctic. The overarching objectives of the CFL project were to contrast the physical and biological systems of the flaw lead open water and thin ice to the adjacent landfast ice cover. The Canadian Research Icebreaker (NGCC Amundsen) completed the first-ever overwintering of a research icebreaker in the flaw lead. She supported a total of 11,000 person days distributed across 295 investigators from 28 different countries. The project obtained many first-ever measurements of a complete suite of physical, biogeochemical, contaminant and marine ecosystem variables across the open water - fast ice contrast. In this paper we present an overview of the early results from this study with a particular focus on the role of fast ice edges in modifying the physical, biological and geochemical processes that occur at the fast ice edge interface. Traditional knowledge of these ice edges illustrates a rich physical and ecological environment. Western science results show the temporal nature of fast ice edges and the associated stimulation of biological productivity make these a particularly important part of the flaw lead system.

  12. Metallic-like photoluminescence and absorption in fused silica surface flaws

    SciTech Connect

    Laurence, T A; Bude, J D; Shen, N; Feldman, T; Miller, P; Steele, W A; Suratwala, T

    2008-09-11

    Using high-sensitivity confocal time-resolved photoluminescence (PL) techniques, we report an ultra-fast PL (40ps-5ns) from impurity-free surface flaws on fused silica, including polished, indented or fractured surfaces of fused silica, and from laser-heated evaporation pits. This PL is excited by the single photon absorption of sub-band gap light, and is especially bright in fractures. Regions which exhibit this PL are strongly absorptive well below the band gap, as evidenced by a propensity to damage with 3.5eV ns-scale laser pulses.

  13. One-sided ultrasonic inspection to detect flaws in CFRP composite solid laminates

    NASA Astrophysics Data System (ADS)

    Im, Kwang-Hee; Zhang, Guilina; Hsu, David K.; Barnard, Dan; Kim, Sun-Kyu; Yang, Yong-Jun; Hwang, Woo-Chae; Yang, In-Young; Park, Je-Woong

    2011-11-01

    The importance of Carbon Fiber reinforced plastics (CFRP) has been generally recognized, and the CFRP composite laminates are widely used. When ultrasonic inspection is applied on actual aircraft components, the part geometry often lacks flat and parallel faces and the benefit of a backwall echo maybe unavailable. So, it is very necessary to detect flaws and defects in the CFRP composite solid laminates due to the flaws of CFRP composite laminates affecting the properties of the laminate. Firstly, we used miniature potted angle beam transducers (designed for generating mode-converted shear waves or Rayleigh waves in steel) on solid laminates of composites. A pair of such transducers was mounted in a holder in a nose-to-nose fashion to be used as a scanning probe on composites. Secondly, a method was utilized to determine the porosity content of a composite lay-up by processing micrograph images of the laminate. The results from the image processing method are compared with existing data. C-scan images of CFRP samples, which were based on the impacted samples were then produced by combining the pitch-catch probe with a portable manual scanner known as the Generic Scanner ("GenScan"). The signal amplitude of pitch-catch C-scan images was also correlated to the volume percent of porosity in carbon composite laminates. Finally, a simulation was performed with the numerical Wave-2000 Code for predicting the ultrasonic wave in the sample.

  14. Analysis of the Mutual Inductance between Two Parallel Plates for the Detection of Surface Flaws

    NASA Technical Reports Server (NTRS)

    Namking, M.; Clendenin, C. G.; Fulton, J. P.; Wincheski, B.

    1992-01-01

    There has recently been much effort behind the development of NDE methods applicable to the detection of surface/subsurface flaws in thin metallic structures with a rapid scan capability. One such method, an electromagnetic technique using a current-sheet parallel to the surface of a specimen in order to induce eddy current flow shows a high potential for satisfying the rapid scan requirement stated above. The technique is based on the detection of flaw-induced magnetic field components normal to the specimen surface by an appropriate detection mechanism positioned above the current-sheet as shown schematically in Fig. 1. As indicated in this figure, the current-sheet separates the source of the normal magnetic field components from the detector in such a way that the electric and magnetic properties of the current-sheet can be a major factor affecting the strength of the detected signals. The purpose of the present study is, therefore, to perform a detailed investigation on the effect of the material properties of the current-sheet on the detected signal strength and to establish a simple theoretical model for the detection mechanism.

  15. Phase encoding schemes for measurement-device-independent quantum key distribution with basis-dependent flaw

    NASA Astrophysics Data System (ADS)

    Tamaki, Kiyoshi; Lo, Hoi-Kwong; Fung, Chi-Hang Fred; Qi, Bing

    2012-04-01

    In this paper, we study the unconditional security of the so-called measurement-device-independent quantum key distribution (MDIQKD) with the basis-dependent flaw in the context of phase encoding schemes. We propose two schemes for the phase encoding: The first one employs a phase locking technique with the use of non-phase-randomized coherent pulses, and the second one uses conversion of standard Bennett-Brassard 1984 (BB84) phase encoding pulses into polarization modes. We prove the unconditional security of these schemes and we also simulate the key generation rate based on simple device models that accommodate imperfections. Our simulation results show the feasibility of these schemes with current technologies and highlight the importance of the state preparation with good fidelity between the density matrices in the two bases. Since the basis-dependent flaw is a problem not only for MDIQKD but also for standard quantum key distribution (QKD), our work highlights the importance of an accurate signal source in practical QKD systems.

  16. Unsupervised flaw segmentation in textile materials under visible and NIR illumination

    NASA Astrophysics Data System (ADS)

    Millán, María S.; Escofet, Jaume; Ralló, Miquel

    2010-05-01

    An unsupervised novelty detection method for automatic flaw segmentation in textile materials that has no need of any defect-free references or a training stage is presented in this paper. The algorithm is based on the structural feature extraction of the weave repeat from the Fourier transform of the sample image. These features are used to define a set of multiresolution bandpass filters adapted to the fabric structure that operate in the Fourier domain. Inverse Fourier transformation, binarization and merging of the information obtained at different scales lead to the output image that contains flaws segmented from the fabric background. The whole process is fully automatic and can be implemented either optical or electronically. Fabrics having a superstructure of colored squares, bands, etc. superimposed to the basic web structure can be advantageously analyzed using NIR illumination and a camera sensitive to this region of the spectrum. The contrast reduction of the superstructure signal in the NIR image facilitates fabric structure inspection and defect segmentation. Underdetection and misdetection errors can be noticeably reduced in comparison with the inspection performed under visible illumination. Experimental results are presented and discussed for a variety of fabrics and defects.

  17. Wavelet analysis applied to thermographic data for the detection of sub-superficial flaws in mosaics

    NASA Astrophysics Data System (ADS)

    Sfarra, Stefano; Regi, Mauro

    2016-06-01

    Up to now, the sun-pulse recorded during the heating (day) and cooling (night) phases has not yet been analyzed by using the infrared thermography (IRT) method through the complex wavelet transform (CWT) technique. CWT can be used with the sun-pulse data in a similar way as the discrete Fourier transform (DFT). In addition, CWT preserves the time information of the signal both in the phasegrams and in the amplitudegrams. In this work, a mosaic sample containing artificial flaws positioned at different depths was inspected into the long wave IR spectrum. It is possible to observe that by comparing defective and defect-free areas, a difference in phase during the thermal diffusion appears. The signal reference, measured on the defect-free area, was subtracted from the other measurement points. The resulting signal thermal contrast, representing the difference of the temporal evolutions of the surface temperature above the defective and defect-free positions, was also plotted. Subsequently, the wavelet phase contrast was computed. The solar radiation influencing the sample was estimated bearing in mind the sun path in the sky, the mosaic orientation and the inclination with respect to its local geographical coordinates. Finally, the ambient parameters have been recorded by a control unit. Although the CWT technique did not provided a sound visualization of the shape of the flaws, it permitted to reflect on the heat release coming from the bituminous material behind the statumen layer. Indeed, it is not atypical to find inclined mosaics to be restored.

  18. One-sided ultrasonic inspection to detect flaws in CFRP composite solid laminates

    NASA Astrophysics Data System (ADS)

    Im, Kwang-Hee; Zhang, Guilina; Hsu, David K.; Barnard, Dan; Kim, Sun-Kyu; Yang, Yong-Jun; Hwang, Woo-Chae; Yang, In-Young; Park, Je-Woong

    2012-04-01

    The importance of Carbon Fiber reinforced plastics (CFRP) has been generally recognized, and the CFRP composite laminates are widely used. When ultrasonic inspection is applied on actual aircraft components, the part geometry often lacks flat and parallel faces and the benefit of a backwall echo maybe unavailable. So, it is very necessary to detect flaws and defects in the CFRP composite solid laminates due to the flaws of CFRP composite laminates affecting the properties of the laminate. Firstly, we used miniature potted angle beam transducers (designed for generating mode-converted shear waves or Rayleigh waves in steel) on solid laminates of composites. A pair of such transducers was mounted in a holder in a nose-to-nose fashion to be used as a scanning probe on composites. Secondly, a method was utilized to determine the porosity content of a composite lay-up by processing micrograph images of the laminate. The results from the image processing method are compared with existing data. C-scan images of CFRP samples, which were based on the impacted samples were then produced by combining the pitch-catch probe with a portable manual scanner known as the Generic Scanner ("GenScan"). The signal amplitude of pitch-catch C-scan images was also correlated to the volume percent of porosity in carbon composite laminates. Finally, a simulation was performed with the numerical Wave-2000 Code for predicting the ultrasonic wave in the sample.

  19. On efficient two-stage adaptive designs for clinical trials with sample size adjustment.

    PubMed

    Liu, Qing; Li, Gang; Anderson, Keaven M; Lim, Pilar

    2012-01-01

    Group sequential designs are rarely used for clinical trials with substantial over running due to fast enrollment or long duration of treatment and follow-up. Traditionally, such trials rely on fixed sample size designs. Recently, various two-stage adaptive designs have been introduced to allow sample size adjustment to increase statistical power or avoid unnecessarily large trials. However, these adaptive designs can be seriously inefficient. To address this infamous problem, we propose a likelihood-based two-stage adaptive design where sample size adjustment is derived from a pseudo group sequential design using cumulative conditional power. We show through numerical examples that this design cannot be improved by group sequential designs. In addition, the approach may uniformly improve any existing two-stage adaptive designs with sample size adjustment. For statistical inference, we provide methods for sequential p-values and confidence intervals, as well as median unbiased and minimum variance unbiased estimates. We show that the claim of inefficiency of adaptive designs by Tsiatis and Mehta ( 2003 ) is logically flawed, and thereby provide a strong defense of Cui et al. ( 1999 ). PMID:22651105

  20. A comparative study of experimental and finite element analysis on submillimeter flaws by laser and ultrasonic excited thermography

    NASA Astrophysics Data System (ADS)

    Zhang, Hai; Fernandes, Henrique; Yu, Lingyao; Hassler, Ulf; Genest, Marc; Robitaille, François; Joncas, Simon; Sheng, Yunlong; Maldague, Xavier

    2016-05-01

    Stitching is used to reduce dry-core and reinforce T-joint structure. However, it might cause new types of flaws, especially submillimeter flaws. In this paper, new approaches including micro-VT, lock-in micro-LLT and micro-LST based on both lock-in and pulse methods are used to detect submillimeter flaws in stitched CFRP. A comparison of laser excitation thermography and micro-VT on micro-porosities is conducted. Micro-CT is used to validate the infrared results. Then, a finite element analysis (FEA) is performed. The geometrical model needed for finite element discretization was developed from micro-CT measurements. The model is validated for the experimental results. Finally a comprehensive experimental and simulation comparison of micro-LLT and micro-LST based on both lock-in and pulse methods is conducted.

  1. Failure behavior of internally pressurized flawed and unflawed steam generator tubing at high temperatures -- Experiments and comparison with model predictions

    SciTech Connect

    Majumdar, S.; Shack, W.J.; Diercks, D.R.; Mruk, K.; Franklin, J.; Knoblich, L.

    1998-03-01

    This report summarizes experimental work performed at Argonne National Laboratory on the failure of internally pressurized steam generator tubing at high temperatures ({le} 700 C). A model was developed for predicting failure of flawed and unflawed steam generator tubes under internal pressure and temperature histories postulated to occur during severe accidents. The model was validated by failure tests on specimens with part-through-wall axial and circumferential flaws of various lengths and depths, conducted under various constant and ramped internal pressure and temperature conditions. The failure temperatures predicted by the model for two temperature and pressure histories, calculated for severe accidents initiated by a station blackout, agree very well with tests performed on both flawed and unflawed specimens.

  2. Flaw growth behavior in thick welded plates of 2219-T87 aluminum at room and cryogenic temperatures

    NASA Technical Reports Server (NTRS)

    Forman, R. G.; Glorioso, S. V.; Medlock, J. D.

    1973-01-01

    Axial load fatigue and fracture tests were conducted on thick welded plates of 2219-T87 aluminum alloy to determine the tensile strength properties and the flaw growth behavior in electron beam, gas metal arc, and pulse current gas tungsten arc welds for plates 6.35 centimeters (2.5 in.) thick. The tests were conducted in room temperature air and in liquid nitrogen environments. Specimens were tested in both the as-welded and the aged after welding conditions. The experimental crack growth rate were correlated with theoretical crack growth rate predictions for semielliptical surface flaws.

  3. An Advanced Flaw-Response Modelling Approach for Inspection Qualification Using a Multi-Agent System Software Platform

    NASA Astrophysics Data System (ADS)

    McKenna, James P.; McLean, Neil; Gachagan, Anthony; McArthur, Stephen D. J.; Hayward, Gordon

    2008-02-01

    This paper describes the application of a Multi-Agent System used in the design and qualification of ultrasonic NDT inspections using theoretical ultrasonic flaw-response modelling. When a large number of models are available the selection of the most appropriate one for a given inspection scenario becomes time-consuming; the disparate nature of the software models prevents easy integration with other NDT software tools to automate this process. A prototype Inspection Qualification Multi-Agent System has been developed which incorporates a rule-based software system to perform the flaw-response model selection procedure.

  4. Assessing allowable take of migratory birds

    USGS Publications Warehouse

    Runge, M.C.; Sauer, J.R.; Avery, M.L.; Blackwell, B.F.; Koneff, M.D.

    2009-01-01

    Legal removal of migratory birds from the wild occurs for several reasons, including subsistence, sport harvest, damage control, and the pet trade. We argue that harvest theory provides the basis for assessing the impact of authorized take, advance a simplified rendering of harvest theory known as potential biological removal as a useful starting point for assessing take, and demonstrate this approach with a case study of depredation control of black vultures (Coragyps atratus) in Virginia, USA. Based on data from the North American Breeding Bird Survey and other sources, we estimated that the black vulture population in Virginia was 91,190 (95% credible interval = 44,520?212,100) in 2006. Using a simple population model and available estimates of life-history parameters, we estimated the intrinsic rate of growth (rmax) to be in the range 7?14%, with 10.6% a plausible point estimate. For a take program to seek an equilibrium population size on the conservative side of the yield curve, the rate of take needs to be less than that which achieves a maximum sustained yield (0.5 x rmax). Based on the point estimate for rmax and using the lower 60% credible interval for population size to account for uncertainty, these conditions would be met if the take of black vultures in Virginia in 2006 was <3,533 birds. Based on regular monitoring data, allowable harvest should be adjusted annually to reflect changes in population size. To initiate discussion about how this assessment framework could be related to the laws and regulations that govern authorization of such take, we suggest that the Migratory Bird Treaty Act requires only that take of native migratory birds be sustainable in the long-term, that is, sustained harvest rate should be

  5. Once again on cardiac transplantation. Flaws in the logic of the proponents.

    PubMed

    Watanabe, Y

    1997-09-01

    In response to a paper written by Drs. Toshima and Kawai trying to refute my earlier article on the movement for cardiac transplantation in Japan, I present the results of my survey of the opinions of medical students and student nurses to prove that polls showing a majority of people supporting organ transplantation from so-called brain-dead persons, to which transplant protagonists rely heavily, merely reflect the failure of the mass media to distribute information on the negative aspects of organ transplantation to the public. Several major flaws in the logic of the proponents are pointed out to show how fragile their theoretical background is. Thus, the need for the distribution of better-balanced information to the public and continued debate on this most serious medical, ethical, social and cultural issue is emphasized.

  6. Fatigue flaw growth assessment and inclusion of stratification to the LBB assessment

    SciTech Connect

    Samohyl, P.

    1997-04-01

    The application of the LBB requires also fatigue flaw growth assessment. This analysis was performed for PWR nuclear power plants types VVER 440/230, VVER 440/213c, VVER 1000/320. Respecting that these NPP`s were designed according to Russian codes that differ from US codes it was needed to compare these approaches. Comparison with our experimental data was accomplished, too. Margins of applicability of the US methods and their modifications for the materials used for construction of Czech and Slovak NPP`s are shown. Computer code accomplishing the analysis according to described method is presented. Some measurement and calculations show that thermal stratifications in horizontal pipelines can lead to additive loads that are not negligible and can be dangerous. An attempt to include these loads induced by steady-state stratification was made.

  7. Sampling flies or sampling flaws? Experimental design and inference strength in forensic entomology.

    PubMed

    Michaud, J-P; Schoenly, Kenneth G; Moreau, G

    2012-01-01

    Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

  8. Gun shows and gun violence: fatally flawed study yields misleading results.

    PubMed

    Wintemute, Garen J; Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A

    2010-10-01

    A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled "The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas" outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors' prior research. The study should not be used as evidence in formulating gun policy.

  9. High-temperature flaw assessment procedure: A state-of-the-art survey

    SciTech Connect

    Ruggles, M.B.; Takahashi, Y.

    1989-05-01

    High-temperature crack growth under cyclic, static, and combined loading is received with an emphasis on fracture mechanics aspects. Experimental studies of the effects of loading history, microstructure, temperature, and environment on crack growth behavior are described and interpreted. The experimental evidence is used to examine crack growth parameters and theoretical models for fatigue, creep, and creep-fatigue crack propagation at elevated temperatures. The limitations of both elastic and elastic-plastic fracture mechanics for high-temperature subcritical crack growth are assessed. Existing techniques for modeling critical crack growth/ligament instability failure are also presented. Related topics of defect modeling and engineering flaw assessment procedures, nondestructive evaluation methods, and probabilistic failure analysis are briefly discussed. 142 refs., 33 figs.

  10. Solar-stimulated flaw and water incursion detection in fiberglass structures

    SciTech Connect

    Schivley, J.D.

    1994-12-31

    Fiberglass is a combination of glass fiber reinforcing material and plastic resin. The advantages far outweigh the disadvantages that are commonly found in commercial structures. Fiberglass does not suffer from dry rot or worms as found with wood; from rust, a common problem with steel; or from electrolysis, common problems with both steel and aluminum. However, compared to steel, fiberglass has low fatigue and buckling strengths. This can cause delaminations where stress concentrations are located. Many other factors contribute to delaminations which are ``invisible`` to the eye. For this reason an infrared thermographic procedure was developed to detect these delaminates and other flaws in fiberglass structures. Due to the confidentiality of this project, neither the name of client or the location of this fiberglass structure will be revealed in this paper. At the time of publication, authorization has not been obtained to release photographs or drawings.

  11. Computer analysis of two-dimensional fatigue flaw-growth problems

    NASA Technical Reports Server (NTRS)

    Forman, R. G.; Kavanaugh, H. C.; Stuckey, B.

    1972-01-01

    A description is given of a computer program for analyzing the crack propagation in cyclic loaded structures. By using equations for the stress intensity factors for surface and embedded flaws, the capability of ascertaining lengthwise crack growth as well as crack growth through the thickness of the structure was determined. Equations used are written in general form so that many other types of crack growth problems, such as through the thickness type cracks, can be analyzed. Provisions have been made in the computer program to analyze crack growth for repeated blocks of variable-amplitude fatigue load spectra. Additional features of the computer program include a variable print interval and a variable integration interval to minimize computer printout and computer run time. A source listing and instructions for using the computer program are included.

  12. Developmental techniques for ultrasonic flaw detection and characterization in stainless steel. [PWR

    SciTech Connect

    Kupperman, D.S.

    1983-04-01

    Flaw detection and characterization by ultrasonic methods is particularly difficult for stainless steel. This paper focuses on two specific problem areas: (a) the inspection of centrifugally cast stainless steel (CCSS) and (b) the differentiation of intergranular stress-corrosion cracking (IGSCC) from geometrical reflectors such as the weld root. To help identify optimal conditions for the ultrasonic inspection of CCSS, the effect of frequency on propagation of longitudinal and shear waves was examined in both isotropic and anisotropic samples. Good results were obtained with isotropic CCSS and 0.5-MHz angle beam shear waves. The use of beam-scattering patterns (i.e. signal amplitude vs skew angle) as a tool for discriminating IGSCC from geometrical reflectors is also discussed.

  13. Controlling the rheological behavior of ceramic slurries and consolidated bodies: Interpenetrating networks and ion size effects

    NASA Astrophysics Data System (ADS)

    Fisher, Matthew Lyle

    Colloidal processing has been demonstrated as an effective technique for increasing the reliability of ceramic components by reducing the flaw populations in sintered bodies. The formation of long-range repulsive potentials produces a dispersed slurry which can be filtered to remove heterogeneities and truncate the flaw size distribution. When the pair potentials are changed from repulsive to weakly attractive, a short-range repulsive potential can be developed in the slurry state which prevents mass segregation, allows particles to consolidate to high volume fractions, and produces plastic consolidated bodies. Plastic behavior in saturated ceramic compacts would allow plastic shape forming technologies to be implemented on advanced ceramic powders. Two networks of different interparticle potential have been mixed to control the rheological properties of slurries and develop clay-like plasticity in consolidated bodies. The elastic modulus and yield stress of slurries were found to increase with volume fraction in a power law fashion. Consolidated bodies containing mixtures of alkylated and non-alkylated powder pack to high volume fraction and exhibit similar flow properties to clay. The mixing of aqueous networks of different pair potential can also be effective in tailoring the flow properties. The flow stress of saturated compacts has been adjusted by the addition of a second network of uncoated particles which is stabilized electrostatically. The influence of the addition of silica of various sizes on the viscosity and zeta potentials of alumina suspensions has been investigated. The adsorption of nano-silica to the surface of alumina shifts the iep. The amount of silica at which the maximum shift in zeta potential occurs is consistent with the silica required to produce the minimum viscosity. This level of silica on the surface is consistent with calculations of the amount necessary for dense random parking of silica spheres around alumina. The influence of

  14. Prediction Of Critical Crack Sizes In Solar Cells

    NASA Technical Reports Server (NTRS)

    Chen, Chern P.

    1989-01-01

    Report presents theoretical analysis of cracking in Si and GaAs solar photovoltaic cells subjected to bending or twisting. Analysis also extended to predict critical sizes for cracks in Ge substrate coated with thin film of GaAs. Analysis leads to general conclusions. Approach and results of study useful in development of guidelines for acceptance or rejection of slightly flawed cells during manufacture.

  15. Fatally Flawed: A Critique of "Fixing the Milwaukee Public Schools: The Limits of Parent-Driven Reform"

    ERIC Educational Resources Information Center

    Carpenter, Dick M., II

    2007-01-01

    This document describes the flaws in an October 2007 Wisconsin Policy Research Institute (WPRI) report on public school choice and parental involvement, "Fixing the Milwaukee Public Schools: The Limits of Parent-Driven Reform." Because the report claims that public school choice and parental involvement have little effect on student performance in…

  16. Unfit for Human Consumption: The Problem of Flawed Writing in Criminal Justice and What to Do about It.

    ERIC Educational Resources Information Center

    Gibbons, Don C.

    1995-01-01

    Provides an account of the processes that are involved in the production of "Crime and Delinquency." Asserts that flawed writing in criminology and criminal justice appears to be a systemic rather than an individual one. Suggests to authors or prospective authors ways in which writing can be improved. (LKS)

  17. The Synoptic Climatology of Ocean-Sea Ice-Atmosphere Coupling over the Cape Bathurst Flaw Lead

    NASA Astrophysics Data System (ADS)

    Asplin, M. G.; Candlish, L. M.; Barber, D. G.; Raddatz, R.

    2009-12-01

    The Circumpolar Flaw Lead (CFL) system is formed when the mobile central pack ice moves away from coastal fast ice, creating an area of open water and thin ice. This process can contribute significant fluxes of heat and moisture to the atmosphere throughout the winter and spring, thus modifying the boundary layer meteorology. The Canadian Research Icebreaker (NGCC Amundsen) overwintered and remained mobile from September 2007 to August 2008 in the Cape Bathurst Flaw Lead, and was the primary field research platform for the International Polar Year Circumpolar Flaw Lead System Study. A ship-based meteorological program monitored surface and upper-level meteorological conditions during the CFL project. These conditions are compared to synoptic-scale meteorology using techniques of synoptic climatology. There are generally two approaches to creating a synoptic climatology: Environment-to-surface, which involves using atmospheric circulation to define weather types, or surface-to-environment, which bases classifications upon a surface variable. In this paper, we propose a technique to generate a surface-to-environment synoptic climatology for the Southern Beaufort Sea region using gridded ice concentration data, and to use it in parallel with an existing environment-to-surface synoptic climatology based upon sea level pressure to examine dynamic and thermodynamic cyclone forcing of the atmosphere-sea ice interface in the Banks Island flaw lead. The existing environment-to-surface synoptic climatology characterizes atmospheric forcing of sea ice motion well, and it is expected that the surface-to-environment synoptic climatology will show how sea ice concentration forces seasonal boundary layer atmospheric profiles over the Cape Bathurst flaw lead.

  18. The frequency of item writing flaws in multiple-choice questions used in high stakes nursing assessments.

    PubMed

    Tarrant, Marie; Knierim, Aimee; Hayes, Sasha K; Ware, James

    2006-12-01

    Multiple-choice questions are a common assessment method in nursing examinations. Few nurse educators, however, have formal preparation in constructing multiple-choice questions. Consequently, questions used in baccalaureate nursing assessments often contain item-writing flaws, or violations to accepted item-writing guidelines. In one nursing department, 2770 MCQs were collected from tests and examinations administered over a five-year period from 2001 to 2005. Questions were evaluated for 19 frequently occurring item-writing flaws, for cognitive level, for question source, and for the distribution of correct answers. Results show that almost half (46.2%) of the questions contained violations of item-writing guidelines and over 90% were written at low cognitive levels. Only a small proportion of questions were teacher generated (14.1%), while 36.2% were taken from testbanks and almost half (49.4%) had no source identified. MCQs written at a lower cognitive level were significantly more likely to contain item-writing flaws. While there was no relationship between the source of the question and item-writing flaws, teacher-generated questions were more likely to be written at higher cognitive levels (p<0.001). Correct answers were evenly distributed across all four options and no bias was noted in the placement of correct options. Further training in item-writing is recommended for all faculty members who are responsible for developing tests. Pre-test review and quality assessment is also recommended to reduce the occurrence of item-writing flaws and to improve the quality of test questions.

  19. The frequency of item writing flaws in multiple-choice questions used in high stakes nursing assessments.

    PubMed

    Tarrant, Marie; Knierim, Aimee; Hayes, Sasha K; Ware, James

    2006-12-01

    Multiple-choice questions are a common assessment method in nursing examinations. Few nurse educators, however, have formal preparation in constructing multiple-choice questions. Consequently, questions used in baccalaureate nursing assessments often contain item-writing flaws, or violations to accepted item-writing guidelines. In one nursing department, 2770 MCQs were collected from tests and examinations administered over a five-year period from 2001 to 2005. Questions were evaluated for 19 frequently occurring item-writing flaws, for cognitive level, for question source, and for the distribution of correct answers. Results show that almost half (46.2%) of the questions contained violations of item-writing guidelines and over 90% were written at low cognitive levels. Only a small proportion of questions were teacher generated (14.1%), while 36.2% were taken from testbanks and almost half (49.4%) had no source identified. MCQs written at a lower cognitive level were significantly more likely to contain item-writing flaws. While there was no relationship between the source of the question and item-writing flaws, teachergenerated questions were more likely to be written at higher cognitive levels (p<0.001). Correct answers were evenly distributed across all four options and no bias was noted in the placement of correct options. Further training in item-writing is recommended for all faculty members who are responsible for developing tests. Pre-test review and quality assessment is also recommended to reduce the occurrence of item-writing flaws and to improve the quality of test questions.

  20. 49 CFR 266.11 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Allowable costs. 266.11 Section 266.11... TRANSPORTATION ACT § 266.11 Allowable costs. Allowable costs include only the following costs which are properly allocable to the work performed: Planning and program operation costs which are allowed under...

  1. 46 CFR 154.421 - Allowable stress.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and...

  2. 46 CFR 154.421 - Allowable stress.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and...

  3. 46 CFR 154.421 - Allowable stress.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and...

  4. 46 CFR 154.440 - Allowable stress.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-522). (b) A greater allowable stress than required in paragraph (a)(1) of this section may...

  5. 46 CFR 154.421 - Allowable stress.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and...

  6. 46 CFR 154.421 - Allowable stress.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and...

  7. 46 CFR 154.440 - Allowable stress.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-ENG). (b) A greater allowable stress than required in paragraph (a)(1) of this section may...

  8. 46 CFR 154.440 - Allowable stress.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-ENG). (b) A greater allowable stress than required in paragraph (a)(1) of this section may...

  9. 46 CFR 154.440 - Allowable stress.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-ENG). (b) A greater allowable stress than required in paragraph (a)(1) of this section may...

  10. Case study of the propagation of a small flaw under PWR loading conditions and comparison with the ASME code design life. Comparison of ASME Code Sections III and XI

    SciTech Connect

    Yahr, G.T.; Gwaltney, R.C.; Richardson, A.K.; Server, W.L.

    1986-01-01

    A cooperative study was performed by EG and G Idaho, Inc., and Oak Ridge National Laboratory to investigate the degree of conservatism and consistency in the ASME Boiler and Pressure Vessel Code Section III fatigue evaluation procedure and Section XI flaw acceptance standards. A single, realistic, sample problem was analyzed to determine the significance of certain points of criticism made of an earlier parametric study by staff members of the Division of Engineering Standards of the Nuclear Regulatory Commission. The problem was based on a semielliptical flaw located on the inside surface of the hot-leg piping at the reactor vessel safe-end weld for the Zion 1 pressurized-water reactor (PWR). Two main criteria were used in selecting the problem; first, it should be a straight pipe to minimize the computational expense; second, it should exhibit as high a cumulative usage factor as possible. Although the problem selected has one of the highest cumulative usage factors of any straight pipe in the primary system of PWRs, it is still very low. The Code Section III fatigue usage factor was only 0.00046, assuming it was in the as-welded condition, and fatigue crack-growth analyses predicted negligible crack growth during the 40-year design life. When the analyses were extended past the design life, the usage factor was less than 1.0 when the flaw had propagated to failure. The current study shows that the criticism of the earlier report should not detract from the conclusion that if a component experiences a high level of cyclic stress corresponding to a fatigue usage factor near 1.0, very small cracks can propagate to unacceptable sizes.

  11. Class Size.

    ERIC Educational Resources Information Center

    Ellis, Thomas I.

    1985-01-01

    After a brief introduction identifying current issues and trends in research on class size, this brochure reviews five recent studies bearing on the relationship of class size to educational effectiveness. Part 1 is a review of two interrelated and highly controversial "meta-analyses" or statistical integrations of research findings on class size,…

  12. Subcellular Size

    PubMed Central

    Marshall, Wallace F.

    2016-01-01

    All of the same conceptual questions about size in organisms apply equally at the level of single cells. What determines the size, not only of the whole cell, but of all its parts? What ensures that subcellular components are properly proportioned relative to the whole cell? How does alteration in organelle size affect biochemical function? Answering such fundamental questions requires us to understand how the size of individual organelles and other cellular structures is determined. Knowledge of organelle biogenesis and dynamics has advanced rapidly in recent years. Does this knowledge give us enough information to formulate reasonable models for organelle size control, or are we still missing something? PMID:25957302

  13. Toward smart aerospace structures: design of a piezoelectric sensor and its analog interface for flaw detection.

    PubMed

    Boukabache, Hamza; Escriba, Christophe; Fourniols, Jean-Yves

    2014-10-31

    Structural health monitoring using noninvasive methods is one of the major challenges that aerospace manufacturers face in this decade. Our work in this field focuses on the development and the system integration of millimetric piezoelectric sensors/ actuators to generate and measure specific guided waves. The aim of the application is to detect mechanical flaws on complex composite and alloy structures to quantify efficiently the global structures' reliability. The study begins by a physical and analytical analysis of a piezoelectric patch. To preserve the structure's integrity, the transducers are directly pasted onto the surface which leads to a critical issue concerning the interfacing layer. In order to improve the reliability and mitigate the influence of the interfacing layer, the global equations of piezoelectricity are coupled with a load transfer model. Thus we can determine precisely the shear strain developed on the surface of the structure. To exploit the generated signal, a high precision analog charge amplifier coupled to a double T notch filter were designed and scaled. Finally, a novel joined time-frequency analysis based on a wavelet decomposition algorithm is used to extract relevant structures signatures. Finally, this paper provides examples of application on aircraft structure specimens and the feasibility of the system is thus demonstrated.

  14. Toward smart aerospace structures: design of a piezoelectric sensor and its analog interface for flaw detection.

    PubMed

    Boukabache, Hamza; Escriba, Christophe; Fourniols, Jean-Yves

    2014-01-01

    Structural health monitoring using noninvasive methods is one of the major challenges that aerospace manufacturers face in this decade. Our work in this field focuses on the development and the system integration of millimetric piezoelectric sensors/ actuators to generate and measure specific guided waves. The aim of the application is to detect mechanical flaws on complex composite and alloy structures to quantify efficiently the global structures' reliability. The study begins by a physical and analytical analysis of a piezoelectric patch. To preserve the structure's integrity, the transducers are directly pasted onto the surface which leads to a critical issue concerning the interfacing layer. In order to improve the reliability and mitigate the influence of the interfacing layer, the global equations of piezoelectricity are coupled with a load transfer model. Thus we can determine precisely the shear strain developed on the surface of the structure. To exploit the generated signal, a high precision analog charge amplifier coupled to a double T notch filter were designed and scaled. Finally, a novel joined time-frequency analysis based on a wavelet decomposition algorithm is used to extract relevant structures signatures. Finally, this paper provides examples of application on aircraft structure specimens and the feasibility of the system is thus demonstrated. PMID:25365457

  15. Convective Origin Gavitational Currents In The Flaw Polynyas of The Laptev Sea Caused By Intensive Freezing

    NASA Astrophysics Data System (ADS)

    Golovin, P.

    Against the background of low winter air temperatures in the Arctic each opening of a quasi-steady flaw polynya causes the burst of the local freezing. Intensive brine ejec- tion in the water column leads to vigorous 3-D turbulent convection. While reaching the seasonal pycnocline by Richardson numbers Ri>10, the 3-D convective turbulent layer poorly interacts with the pycnocline and spreads off the polynya limits under fast ice as a 3-D gravitational turbulent current. Initial, local scheme of baroclinic currents is formed near the fast ice edge, while a compensation counter-current is generated to the polynya in the upper quasi-uniform layer. Henceforward, it transforms into a quasi- 2D mesoscale current is formed because of baroclinic instability and the Cori- olis force. Direction of the quasi-2D mesoscale current in quasi-stationary conditions coincides with orientation of the fast ice edge. It is of a large-scale, and it develops along the whole length of the polynya. The proposed system of formation and evolu- tion of the gravitational currents in the region of the polynya is based on the results of laboratory modeling and in many traits is supported by observational data in the regions of polynyas in the Laptev Sea

  16. Marine Protected Dramas: The Flaws of the Brazilian National System of Marine Protected Areas

    NASA Astrophysics Data System (ADS)

    Gerhardinger, Leopoldo C.; Godoy, Eduardo A. S.; Jones, Peter J. S.; Sales, Gilberto; Ferreira, Beatrice P.

    2011-04-01

    This article discusses the current problems and issues associated with the implementation of a National System of Marine Protected Areas in Brazil. MPA managers and higher governmental level authorities were interviewed about their perceptions of the implementation of a national MPA strategy and the recent changes in the institutional arrangement of government marine conservation agencies. Interviewees' narratives were generally pessimistic and the National System was perceived as weak, with few recognizable marine conservation outcomes on the ground. The following major flaws were identified: poor inter-institutional coordination of coastal and ocean governance; institutional crisis faced by the national government marine conservation agency; poor management within individual MPAs; problems with regional networks of marine protected areas; an overly bureaucratic management and administrative system; financial shortages creating structural problems and a disconnect between MPA policy and its delivery. Furthermore, a lack of professional motivation and a pessimistic atmosphere was encountered during many interviews, a malaise which we believe affects how the entire system is able to respond to crises. Our findings highlight the need for a better understanding of the role of `leadership' in the performance of socio-ecological systems (such as MPA networks), more effective official evaluation mechanisms, more localized audits of (and reforms if necessary to) Brazil's federal biodiversity conservation agency (ICMBio), and the need for political measures to promote state leadership and support. Continuing to focus on the designation of more MPAs whilst not fully addressing these issues will achieve little beyond fulfilling, on paper, Brazil's international marine biodiversity commitments.

  17. THE CHOICE OF OPTIMAL STRUCTURE OF ARTIFICIAL NEURAL NETWORK CLASSIFIER INTENDED FOR CLASSIFICATION OF WELDING FLAWS

    SciTech Connect

    Sikora, R.; Chady, T.; Baniukiewicz, P.; Caryk, M.; Piekarczyk, B.

    2010-02-22

    Nondestructive testing and evaluation are under continuous development. Currently researches are concentrated on three main topics: advancement of existing methods, introduction of novel methods and development of artificial intelligent systems for automatic defect recognition (ADR). Automatic defect classification algorithm comprises of two main tasks: creating a defect database and preparing a defect classifier. Here, the database was built using defect features that describe all geometrical and texture properties of the defect. Almost twenty carefully selected features calculated for flaws extracted from real radiograms were used. The radiograms were obtained from shipbuilding industry and they were verified by qualified operator. Two weld defect's classifiers based on artificial neural networks were proposed and compared. First model consisted of one neural network model, where each output neuron corresponded to different defect group. The second model contained five neural networks. Each neural network had one neuron on output and was responsible for detection of defects from one group. In order to evaluate the effectiveness of the neural networks classifiers, the mean square errors were calculated for test radiograms and compared.

  18. HYDROGEN EFFECTS ON THE BURST PROPERTIES OF TYPE 304L STAINLESS STEEL FLAWED VESSELS

    SciTech Connect

    Morgan, M; Monica Hall, M; Ps Lam, P; Dean Thompson, D

    2008-03-27

    The effect of hydrogen on the burst properties Type 304L stainless steel vessels was investigated. The purpose of the study was to compare the burst properties of hydrogen-exposed stainless steel vessels burst with different media: water, helium gas, or deuterium gas. A second purpose of the tests was to provide data for the development of a predictive finite-element model. The burst tests were conducted on hydrogen-exposed and unexposed axially-flawed cylindrical vessels. The results indicate that samples burst pneumatically had lower volume ductility than those tested hydraulically. Deuterium gas tests had slightly lower ductility than helium gas tests. Burst pressures were not affected by burst media. Hydrogen-charged samples had lower volume ductility and slightly higher burst pressures than uncharged samples. Samples burst with deuterium gas fractured by quasi-cleavage near the inside wall. The results of the tests were used to improve a previously developed predictive finite-element model. The results show that predicting burst behavior requires as a material input the effect of hydrogen on the plastic strain to fracture from tensile tests. The burst test model shows that a reduction in the plastic strain to fracture of the material will result in lower volume ductility without a reduction in burst pressure which is in agreement with the burst results.

  19. Toward Smart Aerospace Structures: Design of a Piezoelectric Sensor and Its Analog Interface for Flaw Detection

    PubMed Central

    Boukabache, Hamza; Escriba, Christophe; Fourniols, Jean-Yves

    2014-01-01

    Structural health monitoring using noninvasive methods is one of the major challenges that aerospace manufacturers face in this decade. Our work in this field focuses on the development and the system integration of millimetric piezoelectric sensors/ actuators to generate and measure specific guided waves. The aim of the application is to detect mechanical flaws on complex composite and alloy structures to quantify efficiently the global structures' reliability. The study begins by a physical and analytical analysis of a piezoelectric patch. To preserve the structure's integrity, the transducers are directly pasted onto the surface which leads to a critical issue concerning the interfacing layer. In order to improve the reliability and mitigate the influence of the interfacing layer, the global equations of piezoelectricity are coupled with a load transfer model. Thus we can determine precisely the shear strain developed on the surface of the structure. To exploit the generated signal, a high precision analog charge amplifier coupled to a double T notch filter were designed and scaled. Finally, a novel joined time-frequency analysis based on a wavelet decomposition algorithm is used to extract relevant structures signatures. Finally, this paper provides examples of application on aircraft structure specimens and the feasibility of the system is thus demonstrated. PMID:25365457

  20. The flaws of laser Doppler in negative-pressure wound therapy research.

    PubMed

    Kairinos, Nicolas; McKune, Andrew; Solomons, Michael; Hudson, Donald A; Kahn, Delawir

    2014-01-01

    Recent studies, using modalities other than laser Doppler, have indicated that perfusion during negative-pressure wound therapy (NPWT) is reduced, contrary to world literature. The aim of the present study was to evaluate whether the measuring technique of the laser Doppler could be influenced by the compressive nature of NPWT dressings and whether this could explain the conflicting findings. A hypothesis that it may be possible for laser Doppler to record similar readings to those obtained during NPWT by merely compressing tissues manually was tested on 12 NPWT dressings, with each undergoing an alternating series of manual compressive forces and NPWT (-125 mmHg). During the periods of NPWT (n = 12), the mean perfusion recording increased in five experiments, reduced in six, and remained unchanged in one. During the period when manual pressure was applied (n = 12), there was a mean increase in perfusion in six experiments and a reduction in six. The type of change in perfusion (increase or decrease) was the same for both NPWT and manual pressure in 10 of the 12 experiments. In conclusion, laser Doppler can incorrectly record increased perfusion when tissues are compressed, implying that it is flawed in the field of NPWT research as tissues are always compressed to some degree by the NPWT dressing.

  1. Flaw assessment guide for high-temperature reactor components subject to creep-fatigue loading

    SciTech Connect

    Ainsworth, R.A. . Berkeley Nuclear Labs.); Ruggles, M.B. ); Takahashi, Y. . Komae Research Lab.)

    1990-10-01

    A high-temperature flaw assessment procedure is described. This procedure is a result of a collaborative effort between Electric Power Research Institute in the United States, Central Research Institute of Electric Power Industry in Japan, and Nuclear Electric plc in the United Kingdom. The procedure addresses preexisting defects subject to creep-fatigue loading conditions. Laws employed to calculate the crack growth per cycle are defined in terms of fracture mechanics parameters and constants related to the component material. The crack-growth laws can be integrated to calculate the remaining life of a component or to predict the amount of crack extension in a given period. Fatigue and creep crack growth per cycle are calculated separately, and the total crack extension is taken as the simple sum of the two contributions. An interaction between the two propagation modes is accounted for in the material properties in the separate calculations. In producing the procedure, limitations of the approach have been identified. 25 refs., 1 fig.

  2. Cross-polarization confocal imaging of subsurface flaws in silicon nitride.

    SciTech Connect

    Liu, Z.; Sun, J. G.; Pei, Z.

    2011-03-01

    A cross-polarization confocal microscopy (CPCM) method was developed to image subsurface flaws in optically translucent silicon nitride (Si{sub 3}N{sub 4}) ceramics. Unlike conventional confocal microscopy, which measures reflected light so is applicable only to transparent and semi-transparent materials, CPCM detects scattered light from subsurface while filtering out the reflected light from ceramic surface. For subsurface imaging, the refractive-index mismatch between imaging (air) and imaged (ceramic) medium may cause image distortion and reduce resolution in the depth direction. This effect, characterized by an axial scaling factor (ASF), was analyzed and experimentally determined for glass and Si{sub 3}N{sub 4} materials. The experimental CPCM system was used to image Hertzian C-cracks generated by various indentation loads in the subsurface of a Si{sub 3}N{sub 4} specimen. It was demonstrated that CPCM may provide detailed information of subsurface cracks, such as crack angle and path, and subsurface microstructural variations.

  3. Robust and reliable banknote authentification and print flaw detection with opto-acoustical sensor fusion methods

    NASA Astrophysics Data System (ADS)

    Lohweg, Volker; Schaede, Johannes; Türke, Thomas

    2006-02-01

    The authenticity checking and inspection of bank notes is a high labour intensive process where traditionally every note on every sheet is inspected manually. However with the advent of more and more sophisticated security features, both visible and invisible, and the requirement of cost reduction in the printing process, it is clear that automation is required. As more and more print techniques and new security features will be established, total quality security, authenticity and bank note printing must be assured. Therefore, this factor necessitates amplification of a sensorial concept in general. We propose a concept for both authenticity checking and inspection methods for pattern recognition and classification for securities and banknotes, which is based on the concept of sensor fusion and fuzzy interpretation of data measures. In the approach different methods of authenticity analysis and print flaw detection are combined, which can be used for vending or sorting machines, as well as for printing machines. Usually only the existence or appearance of colours and their textures are checked by cameras. Our method combines the visible camera images with IR-spectral sensitive sensors, acoustical and other measurements like temperature and pressure of printing machines.

  4. Sexual selection on brain size in shorebirds (Charadriiformes).

    PubMed

    García-Peña, G E; Sol, D; Iwaniuk, A N; Székely, T

    2013-04-01

    Natural selection is considered a major force shaping brain size evolution in vertebrates, whereas the influence of sexual selection remains controversial. On one hand, sexual selection could promote brain enlargement by enhancing cognitive skills needed to compete for mates. On the other hand, sexual selection could favour brain size reduction due to trade-offs between investing in brain tissue and in sexually selected traits. These opposed predictions are mirrored in contradictory relationships between sexual selection proxies and brain size relative to body size. Here, we report a phylogenetic comparative analysis that highlights potential flaws in interpreting relative brain size-mating system associations as effects of sexual selection on brain size in shorebirds (Charadriiformes), a taxonomic group with an outstanding diversity in breeding systems. Considering many ecological effects, relative brain size was not significantly correlated with testis size. In polyandrous species, however, relative brain sizes of males and females were smaller than in monogamous species, and females had smaller brain size than males. Although these findings are consistent with sexual selection reducing brain size, they could also be due to females deserting parental care, which is a common feature of polyandrous species. Furthermore, our analyses suggested that body size evolved faster than brain size, and thus the evolution of body size may be confounding the effect of the mating system on relative brain size. The brain size-mating system association in shorebirds is thus not only due to sexual selection on brain size but rather, to body size evolution and other multiple simultaneous effects.

  5. Automated Flaw Detection Scheme For Cast Austenitic Stainless Steel Weld Specimens Using Hilbert Huang Transform Of Ultrasonic Phased Array Data

    SciTech Connect

    Khan, T.; Majumdar, Shantanu; Udpa, L.; Ramuhalli, Pradeep; Crawford, Susan L.; Diaz, Aaron A.; Anderson, Michael T.

    2012-01-01

    The objective of this work is to develop processing algorithms to detect and localize the flaws using NDE ultrasonic data. Data was collected using cast austenitic stainless steel (CASS) weld specimens on-loan from the U.S. nuclear power industry’s Pressurized Water Reactor Owners Group (PWROG) specimen set. Each specimen consists of a centrifugally cast stainless steel (CCSS) pipe section welded to a statically cast (SCSS) or wrought (WRSS) section. The paper presents a novel automated flaw detection and localization scheme using low frequency ultrasonic phased array inspection signals in the weld and heat affected zone of the base materials. The major steps of the overall scheme are preprocessing and region of interest (ROI) detection followed by the Hilbert Huang transform (HHT) of A-scans in the detected ROIs. HHT offers time-frequency-energy distribution for each ROI. The accumulation of energy in a particular frequency band is used as a classification feature for the particular ROI.

  6. Detection of flaws in a two-dimensional body through measurement of surface temperatures and use of conjugate gradient method

    NASA Astrophysics Data System (ADS)

    Siavashi, Majid; Kowsary, Farshad; Abbasi-Shavazi, Ehsan

    2010-09-01

    This paper aims to obtain parameters (i.e. location and dimensions) relevant to flaws in a two-dimensional body by measuring the temperature on its boundaries. In this endeavour, a steady-state heat conduction problem is formulated, and the geometry under study is subjected to a known heat load, resulting in a specific heat distribution in the body. By using a number of heat sensors, the temperature at selected points on the boundary of the body is obtained. Inverse heat conduction methods implement these temperature data, working toward estimating the flaw parameters. The objective function is optimized using conjugate gradients method, and in solving the direct problem, an FEM code is employed. To check the effectiveness of this method, sample cases with one or more circular, elliptical cavities or cracks in the body, and a case with unknown cavity shape is solved. Finally the ensuing results analyzed.

  7. Non-destructive evaluation means and method of flaw reconstruction utilizing an ultrasonic multi-viewing transducer data acquistion system

    DOEpatents

    Thompson, Donald O.; Wormley, Samuel J.

    1989-03-28

    A multi-viewing ultrasound transducer acquisition system for non-destructive evaluation, flaw detection and flaw reconstruction in materials. A multiple transducer assembly includes a central transducer surrounded by a plurality of perimeter transducers, each perimeter transducer having an axis of transmission which can be angularly oriented with respect to the axis of transmission of the central transducer to intersect the axis of transmission of the central transducer. A control apparatus automatically and remotely positions the transducer assembly with respect to the material by a positioning apparatus and adjusts the pe GRANT REFERENCE This invention was conceived and reduced to practice at least in part under a grant from the Department of Energy under Contract No. W-7407-ENG-82.

  8. Flaw-tolerance and R-curve behavior of liquid-phase-sintered silicon carbides with different microstructures

    SciTech Connect

    Lee, S.K.; Kim, D.K.; Kim, C.H.

    1995-01-01

    {beta}-SiC powder containing 6 wt% Al{sub 2}O{sub 3} and 4 wt% Y{sub 2}O{sub 3} as sintering additives was pressureless sintered at 2,000 C for 1 h (AYE-SiC) and 3 h (AYP-SiC). AYE-SiC consisted of an equiaxed grain structure and AYP-SiC exhibited a microstructure with platelike grains as a result of grain growth related to {beta} {yields} {alpha} phase transformation during sintering. R-curve behavior and flaw tolerance for these silicon carbides were evaluated by the indentation-strength technique. For comparison, the R-curve behavior of conventional sintered, boron- and carbon-doped SiC (SS-SiC) was evaluated. AYE-SiC and AYP-SiC exhibited rising R-curve behavior with toughening exponents of m = 0.042 and m = 0.135, respectively. AYP-SiC exhibited better flaw tolerance and more sharply rising R-curve behavior than AYE-SiC. The more sharply rising R-curve behavior and the better flaw tolerance of AYP-SiC were attributed mainly to grain bridging of crack faces by platelike grains. Because of the high degree of transgranular fracture, SS-SiC exhibited a flat R-curve despite a microstructural feature with platelike grains.

  9. FDAAA legislation is working, but methodological flaws undermine the reliability of clinical trials: a cross-sectional study

    PubMed Central

    Atallah, Álvaro N.

    2015-01-01

    The relationship between clinical research and the pharmaceutical industry has placed clinical trials in jeopardy. According to the medical literature, more than 70% of clinical trials are industry-funded. Many of these trials remain unpublished or have methodological flaws that distort their results. In 2007, it was signed into law the Food and Drug Administration Amendments Act (FDAAA), aiming to provide publicly access to a broad range of biomedical information to be made available on the platform ClinicalTrials (available at https://www.clinicaltrials.gov). We accessed ClinicalTrials.gov and evaluated the compliance of researchers and sponsors with the FDAAA. Our sample comprised 243 protocols of clinical trials of biological monoclonal antibodies (mAb) adalimumab, bevacizumab, infliximab, rituximab, and trastuzumab. We demonstrate that the new legislation has positively affected transparency patterns in clinical research, through a significant increase in publication and online reporting rates after the enactment of the law. Poorly designed trials, however, remain a challenge to be overcome, due to a high prevalence of methodological flaws. These flaws affect the quality of clinical information available, breaching ethical duties of sponsors and researchers, as well as the human right to health. PMID:26131374

  10. Intrinsic tensile properties of cocoon silk fibres can be estimated by removing flaws through repeated tensile tests

    PubMed Central

    Rajkhowa, Rangam; Kaur, Jasjeet; Wang, Xungai; Batchelor, Warren

    2015-01-01

    Silk fibres from silkworm cocoons have lower strength than spider silk and have received less attention as a source of high-performance fibres. In this work, we have used an innovative procedure to eliminate the flaws gradually of a single fibre specimen by retesting the unbroken portion of the fibre, after each fracture test. This was done multiple times so that the final test may provide the intrinsic fibre strength. During each retest, the fibre specimen began to yield once the failure load of the preceding test was exceeded. For each fibre specimen, a composite curve was constructed from multiple tests. The composite curves and analysis show that strengths of mass-produced Muga and Eri cocoon silk fibres increased from 446 to 618 MPa and from 337 to 452 MPa, respectively. Similarly, their toughness increased from 84 to 136 MJ m−3 and from 61 to 104 MJ m−3, respectively. Composite plots produced significantly less inter-specimen variations compared to values from single tests. The fibres with reduced flaws as a result of retests in the tested section have a tensile strength and toughness comparable to naturally spun dragline spider silk with a reported strength of 574 MPa and toughness of 91–158 MJ m−3, which is used as a benchmark for developing high-performance fibres. This retesting approach is likely to provide useful insights into discrete flaw distributions and intrinsic mechanical properties of other fatigue-resistant materials. PMID:25948613

  11. 10 CFR 600.317 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OMB Circular A-122 is determined in accordance with the for-profit costs principles in 48 CFR part 31... Organizations.” (iii) Hospitals. Allowability is determined in accordance with the provisions of 45 CFR part 74... Allowable costs. (a) DOE determines allowability of costs in accordance with the cost principles...

  12. 7 CFR 550.25 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... at 2 CFR part 230. The allowability of costs incurred by institutions of higher education is... at 2 CFR part 225. The allowability of costs incurred by non-profit organizations is determined in... Institutions” codified at 2 CFR 220. The allowability of costs incurred by hospitals is determined...

  13. 20 CFR 211.8 - Displacement allowance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Displacement allowance. 211.8 Section 211.8 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.8 Displacement allowance. An allowance paid to an employee because he has...

  14. 20 CFR 211.8 - Displacement allowance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Displacement allowance. 211.8 Section 211.8 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.8 Displacement allowance. An allowance paid to an employee because he has...

  15. 20 CFR 211.8 - Displacement allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Displacement allowance. 211.8 Section 211.8 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.8 Displacement allowance. An allowance paid to an employee because he has...

  16. 20 CFR 211.8 - Displacement allowance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Displacement allowance. 211.8 Section 211.8 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.8 Displacement allowance. An allowance paid to an employee because he has...

  17. 20 CFR 211.8 - Displacement allowance.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Displacement allowance. 211.8 Section 211.8 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT CREDITABLE RAILROAD COMPENSATION § 211.8 Displacement allowance. An allowance paid to an employee because he has...

  18. 44 CFR 206.228 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Allowable costs. General policies for determining allowable costs are established in 44 CFR 13.22. Exceptions to those policies as allowed in 44 CFR 13.4 and 13.6 are explained below. (a) Eligible direct... accordance with 44 CFR part 207. (b)...

  19. 44 CFR 204.63 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....63 Allowable costs. 44 CFR 13.22 establishes general policies for determining allowable costs. (a) We will reimburse direct costs for the administration of a fire management assistance grant under 44 CFR... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Allowable costs....

  20. 50 CFR 80.15 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., see 5 CFR 1310.3.). (b) What is required to determine the allowability of costs? Source documents or... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Allowable costs. 80.15 Section 80.15... WILDLIFE RESTORATION AND DINGELL-JOHNSON SPORT FISH RESTORATION ACTS § 80.15 Allowable costs. (a) What...

  1. 50 CFR 85.41 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... applicable Federal cost principles in 43 CFR 12.60(b). Purchase of informational signs, program signs, and... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Allowable costs. 85.41 Section 85.41... Use/Acceptance of Funds § 85.41 Allowable costs. (a) Allowable grant costs are limited to those...

  2. 34 CFR 675.33 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 3 2011-07-01 2011-07-01 false Allowable costs. 675.33 Section 675.33 Education... costs. (a)(1) Allowable and unallowable costs. Except as provided in paragraph (a)(2) of this section, costs reasonably related to carrying out the programs described in § 675.32 are allowable. (2)...

  3. 42 CFR 417.534 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Allowable costs. 417.534 Section 417.534 Public... PLANS Medicare Payment: Cost Basis § 417.534 Allowable costs. (a) Definition—Allowable costs means the direct and indirect costs, including normal standby costs incurred by the HMO or CMP, that are proper...

  4. 42 CFR 417.802 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Allowable costs. 417.802 Section 417.802 Public... PLANS Health Care Prepayment Plans § 417.802 Allowable costs. (a) General rule. The costs that are considered allowable for HCPP reimbursement are the same as those for reasonable cost HMOs and CMPs...

  5. 45 CFR 1180.56 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 1180.56 Section 1180.56 Public... by a Grantee General Administrative Responsibilities § 1180.56 Allowable costs. (a) Determination of costs allowable under a grant is made in accordance with government-wide cost principles in...

  6. 34 CFR 304.21 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education Department General Administrative Regulations in 34 CFR 75.530 through 75.562, the following items are... 34 Education 2 2011-07-01 2010-07-01 true Allowable costs. 304.21 Section 304.21...

  7. 34 CFR 80.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... 34 Education 1 2010-07-01 2010-07-01 false Allowable costs. 80.22 Section 80.22 Education Office... Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1) The allowable...

  8. 34 CFR 80.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... 34 Education 1 2011-07-01 2011-07-01 false Allowable costs. 80.22 Section 80.22 Education Office... Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1) The allowable...

  9. 42 CFR 417.802 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Allowable costs. 417.802 Section 417.802 Public... PLANS Health Care Prepayment Plans § 417.802 Allowable costs. (a) General rule. The costs that are considered allowable for HCPP reimbursement are the same as those for reasonable cost HMOs and CMPs...

  10. 34 CFR 304.21 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education Department General Administrative Regulations in 34 CFR 75.530 through 75.562, the following items are... 34 Education 2 2010-07-01 2010-07-01 false Allowable costs. 304.21 Section 304.21...

  11. 42 CFR 417.534 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Allowable costs. 417.534 Section 417.534 Public... PLANS Medicare Payment: Cost Basis § 417.534 Allowable costs. (a) Definition—Allowable costs means the direct and indirect costs, including normal standby costs incurred by the HMO or CMP, that are proper...

  12. 45 CFR 1157.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... named in OBM Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 1157.22 Section 1157.22 Public... Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1) The allowable...

  13. 24 CFR 17.43 - Allowable claims.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Allowable claims. (a) A claim may be allowed only if: (1) The damage or loss was not caused wholly or partly...) of this section, and the other provisions of this subpart, any claim for damage to, or loss of... types of claims may be allowed, unless excluded by §§ 17.44 and 17.45: (1) Property loss or damage...

  14. 44 CFR 206.228 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Allowable costs. 206.228... Allowable costs. General policies for determining allowable costs are established in 44 CFR 13.22... costs for major disasters and emergencies will be paid in accordance with 44 CFR part 207. (b)...

  15. 44 CFR 206.439 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Allowable costs. 206.439... Allowable costs. (a) General requirements for determining allowable costs are established in 44 CFR 13.22... section. (b) Administrative and management costs for major disasters will be paid in accordance with...

  16. 46 CFR 154.447 - Allowable stress.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for...

  17. 46 CFR 154.447 - Allowable stress.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for...

  18. 46 CFR 154.447 - Allowable stress.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for...

  19. 46 CFR 154.428 - Allowable stress.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable...

  20. 46 CFR 154.428 - Allowable stress.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable...

  1. 46 CFR 154.428 - Allowable stress.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable...

  2. 46 CFR 154.428 - Allowable stress.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable...

  3. 46 CFR 154.428 - Allowable stress.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable...

  4. 46 CFR 154.447 - Allowable stress.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for...

  5. 46 CFR 154.447 - Allowable stress.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for...

  6. 34 CFR 304.21 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false Allowable costs. 304.21 Section 304.21 Education... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education Department General Administrative Regulations in 34 CFR 75.530 through 75.562, the following items...

  7. 34 CFR 304.21 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 2 2014-07-01 2013-07-01 true Allowable costs. 304.21 Section 304.21 Education... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education Department General Administrative Regulations in 34 CFR 75.530 through 75.562, the following items...

  8. 34 CFR 304.21 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false Allowable costs. 304.21 Section 304.21 Education... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education Department General Administrative Regulations in 34 CFR 75.530 through 75.562, the following items...

  9. A Critical Assessment of Child Custody Evaluations: Limited Science and a Flawed System.

    PubMed

    Emery, Robert E; Otto, Randy K; O'Donohue, William T

    2005-07-01

    further scientific investigation. We see the system for resolving custody disputes as deeply flawed, for reasons that go beyond the problem of limited science. The coupling of the vague "best interests of the child" test with the American adversary system of justice puts judges in the position of trying to perform an impossible task, and it exacerbates parental conflict and problems in parenting and coparenting, which psychological science clearly shows to be key factors predicting children's psychological difficulties in response to their parents' separation and divorce. Our analysis of the flawed system, together with our desire to sharply limit custody disputes and custody evaluations, leads us to propose three reforms. First, we urge continued efforts to encourage parents to reach custody agreements on their own-in divorce mediation, through collaborative law, in good-faith attorney negotiations, in therapy, and in other forums. Some such efforts have been demonstrated to improve parent-parent and parent-child relationships long after divorce, and they embrace the philosophical position that, in the absence of abuse or neglect, parents themselves should determine their children's best interests after separation, just as they do in marriage. Second, we urge state legislatures to move toward adopting more clear and determinative custody rules, a step that would greatly clarify the terms of the marriage contract, limit the need for custody evaluations, and sharply narrow the scope of the evaluation process. We find particular merit in the proposed "approximation rule" (recently embraced by the American Law Institute), in which postdivorce parenting arrangements would approximate parenting involvement in marriage. Third and finally, we recommend that custody evaluators follow the law and only offer opinions for which there is an adequate scientific basis. Related to this, we urge professional bodies to enact more specific standards of practice on this and related issues.

  10. Evaluating the evidence for evidence-based medicine: are randomized clinical trials less flawed than other forms of peer-reviewed medical research?

    PubMed

    Steen, R Grant; Dager, Stephen R

    2013-09-01

    Evidence-based medicine considers randomized clinical trials (RCTs) to be the strongest form of evidence for clinical decision making. To test the hypothesis that RCTs have fewer methodological flaws than non-RCTs, limitations of 17,591 RCTs and 39,029 non-RCTs were characterized. Panels of experts assembled to write meta-analyses evaluated this literature to determine which articles should be included in 316 meta-analytic reviews. Overall, 38.7% of RCTs evaluated were excluded from review for an identified flaw. Commonly identified flaws in RCTs were as follows: insufficient data provided to evaluate the study (9.6% of 17,591 RCTs); inadequate randomization (9.0%); inadequate blinding (4.9%); and duplicative publication (4.4%). Overall, 20.2% of all published medical research has an identified methodological flaw, with RCTs having as many limitations as non-RCTs.

  11. Size Matters

    ERIC Educational Resources Information Center

    Gehring, John

    2004-01-01

    This article describes the immense size of Unity Junior High School in Cicero, Illinois and the opinions of various people regarding its size. The school has more than 2,700 students, seventeen acres, eighty-eight faculty lounges, and ninety-six security cameras. Administrators hope the school--"Cicero's crown jewel," as the school district's Web…

  12. Evaluating asymmetry in prosthetic gait with step-length asymmetry alone is flawed.

    PubMed

    Roerdink, Melvyn; Roeles, Sanne; van der Pas, Sanne C H; Bosboom, Otelie; Beek, Peter J

    2012-03-01

    Prosthetic gait is often asymmetric in step length, but the direction of this asymmetry varies inconsistently across amputees. This situation is akin to that seen in stroke patients, where step-length asymmetry has been shown to be the additive result of asymmetries in trunk progression and asymmetries in forward foot placement relative to the trunk. The present study examined the validity of this notion in three trans-tibial and seven trans-femoral amputees wearing a unilateral prosthesis while walking over a walkway at a comfortable and slower-than-comfortable speed. The latter manipulation was added to examine the expectation that the magnitude of the trunk-progression asymmetry - attributable to a weaker propulsion generating capacity on the prosthetic side - would be smaller when walking slower because of the diminished propulsion demands. Step length, forward foot placement relative to the trunk, and trunk progression of prosthetic and non-prosthetic steps, as well as asymmetries therein, were quantified. The direction of step-length and forward foot placement asymmetries varied inconsistently across (but consistently within) participants. As expected, step-length asymmetry depended on the combination of asymmetries in forward foot placement and trunk progression, with a smaller contribution of trunk-progression asymmetry at slow speed. These results extend our previous finding for hemiplegic patients that an analysis of gait asymmetry in terms of step length alone is flawed to prosthetic gait, implying that knowledge of asymmetries in trunk progression and forward foot placement relative to the trunk is required to help elucidate the contribution of underlying impairments (viz. propulsion generating capacity) and adopted compensations on prosthetic gait asymmetry.

  13. Current and historical perspectives on methodological flaws in processing umbilical cord blood.

    PubMed

    Mehrishi, J N

    2013-11-01

    Umbilical cord blood (UCB) hematopoietic stem cells (HSC-CD34+) are valuable for treating malignant or nonmalignant disease. Processing UCB by HESPAN-6% and anti-CD34-Miltenyi particles provides insufficient cells for treating adults. Physicochemical-electrokinetic studies on UCB-mononuclear cells (MNCs) under conditions of delayed processing, ice or very low temperatures, and some cell separation media identified artifacts introduced by procedures. Adsorption of biomaterials from cell damage by temperature, degradation products after using enzymes, harsh reagents, dithiothreitol, and HESPAN affect cell properties and distribution. Miltenyi particles internalized by cells could release iron that accumulating in liver or spleen would then risk toxicity. Summary topics included the effects of temperature, HESPAN (fast sedimenting agent), glycoproteases, DNase, and dithiothreitol risk affecting cell receptors in recognition, "homing," leading to possible unintended iatrogenic bioeffects should such cells be transfused into humans. The loss of undetectable and uncaptured low CD34 antigen-bearing cells by Miltenyi particles seems to occur when the current methods of isolation of CD34+ cells and other cells are critically assessed. The purpose here is to highlight and suggest avoiding the procedural flaws involved. Preventing ice temperatures avoids ice-damaged platelets releasing biomaterials that are adsorbed on cells altering UBC-MNCs/HSC properties and cell loss. Omitting the positive selection with antibody-linked Miltenyi particles obviates the use of harsh reagents to release the cells. Internalized Miltenyi particles are a toxicity hazard that needs investigations. Achieving approximately 5% yields of CD34+ cells (153 × 10(5) /110 mL cord-placenta blood) is a major advance holding great promise, for the first time increasing the prospect of stem cell therapy of 70-kg adults, using a single UCB donation (with dose of 1.5 × 10(5) cells/kg) and

  14. Development of a method to characterize high-protein dairy powders using an ultrasonic flaw detector.

    PubMed

    Hauser, M; Amamcharla, J K

    2016-02-01

    Dissolution behavior of high-protein dairy powders plays a critical role for achieving functional and nutritional characteristics of a finished food product. Current methods for evaluating powder dissolution properties are time consuming, difficult to reproduce, and subjective. Ultrasound spectroscopy is a rapid and precise method, but requires expensive equipment and skilled technicians to carry out the tests. In the present study, an ultrasonic flaw detector (UFD) was used as an economical alternative to characterize the powder dissolution properties. The objective of study was to develop a method to characterize the dissolution behavior of milk protein concentrate (MPC) using a UFD. The experimental setup included a UFD connected to a 1-MHz immersion transducer that was kept a constant distance from a reflector plate. To validate the method, 2 batches of MPC80 from a commercial manufacturer were procured and stored at 25 and 40°C for 4 wk. Focus beam reflectance measurement and solubility index were used as reference methods. Relative ultrasound velocity and ultrasound attenuation were acquired during the dissolution of MPC samples. To characterize the MPC dissolution, 4 parameters including standard deviation of relative velocity, area under the attenuation curve, and peak attenuation were extracted from ultrasound data. As the storage temperature and time increased, the area under the attenuation curve and peak height decreased, indicating a loss of solubility. The proposed UFD-based method was able to capture the changes in dissolution of MPC during storage at 25 and 40°C. It was observed that a high-quality MPC had a low standard deviation and a larger area under the attenuation curve. As the MPC aged at 40°C, the particle dispersion rate decreased and, consequently, an increase in standard deviation and reduction in area were observed. Overall, the UFD can be a low-cost method to characterize the dissolution behavior of high-protein dairy powders.

  15. DEVELOPMENT AND APPLICATION OF MATERIALS PROPERTIES FOR FLAW STABILITY ANALYSIS IN EXTREME ENVIRONMENT SERVICE

    SciTech Connect

    Sindelar, R; Ps Lam, P; Andrew Duncan, A; Bruce Wiersma, B; Karthik Subramanian, K; James Elder, J

    2007-04-18

    Discovery of aging phenomena in the materials of a structure may arise after its design and construction that impact its structural integrity. This condition can be addressed through a demonstration of integrity with the material-specific degraded conditions. Two case studies of development of fracture and crack growth property data, and their application in development of in-service inspection programs for nuclear structures in the defense complex are presented. The first case study covers the development of fracture toughness properties in the form of J-R curves for rolled plate Type 304 stainless steel with Type 308 stainless steel filler in the application to demonstrate the integrity of the reactor tanks of the heavy water production reactors at the Savannah River Site. The fracture properties for the base, weld, and heat-affected zone of the weldments irradiated at low temperatures (110-150 C) up to 6.4 dpa{sub NRT} and 275 appm helium were developed. An expert group provided consensus for application of the irradiated properties for material input to acceptance criteria for ultrasonic examination of the reactor tanks. Dr. Spencer H. Bush played a lead advisory role in this work. The second case study covers the development of fracture toughness for A285 carbon steel in high level radioactive waste tanks. The approach in this case study incorporated a statistical experimental design for material testing to address metallurgical factors important to fracture toughness. Tolerance intervals were constructed to identify the lower bound fracture toughness for material input to flaw disposition through acceptance by analysis.

  16. Development of J-integral based UT flaw acceptance criteria for Savannah River reactor tanks

    SciTech Connect

    Mehta, H.S.; Ranganath, S.; Awadalla, N.G.; Sindelar, R.L.; Caskey, G.R. Jr.; Daugherty, W.L.

    1991-12-31

    The tank of a Savannah River Site reactor is a cylinder approximately 16 feet in diameter and 14 feet high and is not pressurized except for a 5 psig helium blanket gas in addition to the hydrostatic head of the heavy water (D{sub 2}O) moderator. The tank is made of Type 304 Stainless steel fabricated into cylindrical shells with 0.5 inch thick four to six wrought plates per vessel. The shell was made up in two flat half-sections for later rolling and welding. The tank bottom section containing the moderator effluent nozzles was welded to the shell in a T-Joint configuration. An ultrasonic (UT) in-service inspection program has been developed for the examination of these reactor tanks. Prior to the initiation of these inspections, criteria for the disposition of any indications that may be found were required. This paper describes the fracture mechanics evaluations that formed the technical bases for the flaw acceptance criteria. The fracture mechanics evaluation considered detailed finite element calculated stress states in the various regions of the tanks, measured irradiated fracture toughness properties (irradiated condition material J-R curves), fluence levels in the tanks, and intergranular stress corrosion cracking growth rates in the reactor environment. The irradiation program was conducted at the High Flux Isotope Reactor at Oak Ridge National Laboratory. Tensile and fracture toughness data were obtained from 36 compact tension, tensile and Charpy V-notch specimens. Through wall cracks are postulated in various regions of the tank and critical crack lengths are calculated by the elastic-plastic fracture mechanics based J-Integral/Tearing Modulus (J/T) approach. The applied values of J-integral were calculated by the well-known GE/EPRI estimation scheme. Acceptable crack lengths are then calculated following generally accepted safety factors based on the ASME Pressure Vessel Code. The acceptance criteria are then briefly described.

  17. Development of J-integral based UT flaw acceptance criteria for Savannah River reactor tanks

    SciTech Connect

    Mehta, H.S.; Ranganath, S. . Nuclear Energy Div.); Awadalla, N.G.; Sindelar, R.L.; Caskey, G.R. Jr.; Daugherty, W.L. )

    1991-01-01

    The tank of a Savannah River Site reactor is a cylinder approximately 16 feet in diameter and 14 feet high and is not pressurized except for a 5 psig helium blanket gas in addition to the hydrostatic head of the heavy water (D{sub 2}O) moderator. The tank is made of Type 304 Stainless steel fabricated into cylindrical shells with 0.5 inch thick four to six wrought plates per vessel. The shell was made up in two flat half-sections for later rolling and welding. The tank bottom section containing the moderator effluent nozzles was welded to the shell in a T-Joint configuration. An ultrasonic (UT) in-service inspection program has been developed for the examination of these reactor tanks. Prior to the initiation of these inspections, criteria for the disposition of any indications that may be found were required. This paper describes the fracture mechanics evaluations that formed the technical bases for the flaw acceptance criteria. The fracture mechanics evaluation considered detailed finite element calculated stress states in the various regions of the tanks, measured irradiated fracture toughness properties (irradiated condition material J-R curves), fluence levels in the tanks, and intergranular stress corrosion cracking growth rates in the reactor environment. The irradiation program was conducted at the High Flux Isotope Reactor at Oak Ridge National Laboratory. Tensile and fracture toughness data were obtained from 36 compact tension, tensile and Charpy V-notch specimens. Through wall cracks are postulated in various regions of the tank and critical crack lengths are calculated by the elastic-plastic fracture mechanics based J-Integral/Tearing Modulus (J/T) approach. The applied values of J-integral were calculated by the well-known GE/EPRI estimation scheme. Acceptable crack lengths are then calculated following generally accepted safety factors based on the ASME Pressure Vessel Code. The acceptance criteria are then briefly described.

  18. Least Squares Best Fit Method for the Three Parameter Weibull Distribution: Analysis of Tensile and Bend Specimens with Volume or Surface Flaw Failure

    NASA Technical Reports Server (NTRS)

    Gross, Bernard

    1996-01-01

    Material characterization parameters obtained from naturally flawed specimens are necessary for reliability evaluation of non-deterministic advanced ceramic structural components. The least squares best fit method is applied to the three parameter uniaxial Weibull model to obtain the material parameters from experimental tests on volume or surface flawed specimens subjected to pure tension, pure bending, four point or three point loading. Several illustrative example problems are provided.

  19. Prospects and limitations of digital Shearography and Active Thermography in finding and rating flaws in CFRP sandwich parts with honeycomb core

    NASA Astrophysics Data System (ADS)

    Gruber, J.; Mayr, G.; Hendorfer, G.

    2012-05-01

    This work shows the prospects and limitations of the non-destructive testing methods Digital Shearography and Active Thermography when applied to CFRP sandwich parts with honeycomb cores. Two specimens with different core materials (aluminum, NOMEX) and artificial flaws such as delaminations, disbonds and inclusions of foreign material, are tested with Digital Shearography and Pulse Thermography including Pulse Phase Thermography. Both methods provide a good ability for finding and rating the flaws.

  20. A Surface-to-Environment Synoptic Typing Approach to Classify Cyclone Forcing of Ocean-Sea Ice-Atmosphere Coupling within the Cape Bathurst Flaw Lead

    NASA Astrophysics Data System (ADS)

    Asplin, M. G.; Barber, D. G.; Candlish, L. M.; Raddatz, R.

    2010-12-01

    The Circumpolar Flaw Lead (CFL) system represents a key dynamic physical and biophysical interface between the atmosphere, ocean, and sea ice in the Arctic Basin. The CFL system is an area of open water and thin ice, and is formed where the mobile central pack ice moves away from coastal fast ice. This process can release large heat and moisture fluxes to the atmosphere throughout the winter and spring, thus modifying the regional boundary layer climate. This process was monitored throughout the eleven-month long International Polar Year Circumpolar Flaw Lead System Study, which involved over-wintering the Canadian Research Icebreaker CCGS Amundsen from September 2007 to August 2008 in the Cape Bathurst Flaw Lead. In this paper, we propose a technique to generate a surface-to-environment synoptic climatology for the Cape Bathurst Flaw Lead region using gridded ice concentration data, and link it to an existing environment-to-surface synoptic climatology based upon sea level pressure to examine dynamic and thermodynamic cyclone forcing of the atmosphere-sea ice interface in the Banks Island flaw lead. The existing environment-to-surface synoptic climatology characterizes atmospheric forcing of sea ice motion well, and it is expected that the surface-to-environment synoptic climatology will be effective at classifying how sea ice concentration forces seasonal boundary layer atmospheric profiles over the Cape Bathurst flaw lead. Cyclone-driven heat and moisture coupling between the ocean and atmosphere within the boundary layer can then be assessed.

  1. 20 CFR 631.84 - Allowable projects.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Allowable projects. 631.84 Section 631.84... THE JOB TRAINING PARTNERSHIP ACT Disaster Relief Employment Assistance § 631.84 Allowable projects...) Shall be used exclusively to provide employment on projects that provide food, clothing, shelter...

  2. 27 CFR 28.334 - Credit allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Credit allowance. 28.334... OF THE TREASURY LIQUORS EXPORTATION OF ALCOHOL Action on Claims § 28.334 Credit allowance. Where the credit relates to internal revenue taxes on beer that have been determined but not yet paid by...

  3. 27 CFR 28.334 - Credit allowance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Credit allowance. 28.334... OF THE TREASURY LIQUORS EXPORTATION OF ALCOHOL Action on Claims § 28.334 Credit allowance. Where the credit relates to internal revenue taxes on beer that have been determined but not yet paid by...

  4. 27 CFR 28.334 - Credit allowance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Credit allowance. 28.334... OF THE TREASURY LIQUORS EXPORTATION OF ALCOHOL Action on Claims § 28.334 Credit allowance. Where the credit relates to internal revenue taxes on beer that have been determined but not yet paid by...

  5. 27 CFR 28.334 - Credit allowance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Credit allowance. 28.334... OF THE TREASURY ALCOHOL EXPORTATION OF ALCOHOL Action on Claims § 28.334 Credit allowance. Where the credit relates to internal revenue taxes on beer that have been determined but not yet paid by...

  6. 27 CFR 28.334 - Credit allowance.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Credit allowance. 28.334... OF THE TREASURY ALCOHOL EXPORTATION OF ALCOHOL Action on Claims § 28.334 Credit allowance. Where the credit relates to internal revenue taxes on beer that have been determined but not yet paid by...

  7. 20 CFR 437.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CFR Part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to cost-type...

  8. 34 CFR 642.40 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Allowable costs. 642.40 Section 642.40 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION TRAINING PROGRAM FOR FEDERAL TRIO PROGRAMS What Conditions Must Be Met by a Grantee? § 642.40 Allowable costs....

  9. 10 CFR 600.222 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... than a hospital and an organization named in OBM Circular A-122 as not subject to that circular 48 CFR... organization named in OMB Circular A-122 as not subject to that circular. 48 CFR 931.2 Hospitals 45 CFR part 74... allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs in...

  10. 45 CFR 92.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... to that circular 48 CFR Part 31. Contract Cost Principles and Procedures, or uniform cost accounting... grantee or subgrantee. (b) Applicable cost principles. For each kind of organization, there is a set of Federal principles for determining allowable costs. Allowable costs will be determined in accordance...

  11. 15 CFR 24.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply with...) Applicable cost principles. For each kind of organization, there is a set of Federal principles for determining allowable costs. Allowable costs will be determined in accordance with the cost...

  12. 20 CFR 617.46 - Travel allowance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... mile at the prevailing mileage rate authorized under the Federal travel regulations (see 41 CFR part... the same trip in the same vehicle. (2) Lodging and meals. The cost allowable for lodging and meals for... prevailing per diem allowance rate authorized under the Federal travel regulations (see 41 CFR part...

  13. 20 CFR 617.46 - Travel allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... mile at the prevailing mileage rate authorized under the Federal travel regulations (see 41 CFR part... the same trip in the same vehicle. (2) Lodging and meals. The cost allowable for lodging and meals for... prevailing per diem allowance rate authorized under the Federal travel regulations (see 41 CFR part...

  14. 30 CFR 206.160 - Operating allowances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Operating allowances. 206.160 Section 206.160 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT PRODUCT VALUATION Federal Gas § 206.160 Operating allowances. Notwithstanding any other provisions...

  15. Moral Appraisals Affect Doing/Allowing Judgments

    ERIC Educational Resources Information Center

    Cushman, Fiery; Knobe, Joshua; Sinnott-Armstrong, Walter

    2008-01-01

    An extensive body of research suggests that the distinction between doing and allowing plays a critical role in shaping moral appraisals. Here, we report evidence from a pair of experiments suggesting that the converse is also true: moral appraisals affect doing/allowing judgments. Specifically, morally bad behavior is more likely to be construed…

  16. Allocation of Allowances and Associated Family Practices.

    ERIC Educational Resources Information Center

    Kerr, M. Kaye; Cheadle, Tannis

    This study gathered information on general family practices concerning allowances given to children, parental reasons for the provision of allowances, the bases for their administration, and the frequency of conflicts generated around them. The subjects were 81 parents of elementary school children in a midwest Canadian city. Subjects completed…

  17. 20 CFR 632.258 - Allowable activities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INDIAN AND NATIVE AMERICAN EMPLOYMENT AND TRAINING PROGRAMS Summer Youth Employment and Training Programs § 632.258 Allowable activities. Allowable activities are those listed in § 632.78-80 except that community service employment is...

  18. 20 CFR 632.258 - Allowable activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INDIAN AND NATIVE AMERICAN EMPLOYMENT AND TRAINING PROGRAMS Summer Youth Employment and Training Programs § 632.258 Allowable activities. Allowable activities are those listed in § 632.78-80 except that community service employment is...

  19. 42 CFR 417.802 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) MEDICARE PROGRAM (CONTINUED) HEALTH MAINTENANCE ORGANIZATIONS, COMPETITIVE MEDICAL PLANS, AND HEALTH CARE PREPAYMENT PLANS Health Care Prepayment Plans § 417.802 Allowable costs. (a) General rule. The costs that are... 42 Public Health 3 2014-10-01 2014-10-01 false Allowable costs. 417.802 Section 417.802...

  20. 4 CFR 5.6 - Allowances.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false Allowances. 5.6 Section 5.6 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM COMPENSATION § 5.6 Allowances. The provisions of chapter 59 of title 5, U.S. Code and the implementing regulations for the Executive Branch apply to Government...

  1. 20 CFR 617.46 - Travel allowance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... mile at the prevailing mileage rate authorized under the Federal travel regulations (see 41 CFR part... prevailing per diem allowance rate authorized under the Federal travel regulations (see 41 CFR part 101-7... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Travel allowance. 617.46 Section...

  2. 28 CFR 66.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... applicable to the organization incurring the costs. The following chart lists the kinds of organizations and... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Allowable costs. 66.22 Section 66.22... Administration § 66.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1)...

  3. 44 CFR 208.33 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Allowable costs. 208.33... HOMELAND SECURITY DISASTER ASSISTANCE NATIONAL URBAN SEARCH AND RESCUE RESPONSE SYSTEM Response Cooperative Agreements § 208.33 Allowable costs. (a) Cost neutrality. DHS policy is that an Alert or Activation should...

  4. 30 CFR 1206.160 - Operating allowances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Operating allowances. 1206.160 Section 1206.160 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR Natural Resources Revenue PRODUCT VALUATION Federal Gas § 1206.160 Operating allowances. Notwithstanding any...

  5. 21 CFR 1403.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and an organization named in OMB Circular A-122 as not subject to that circular 48 CFR part 31... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Allowable costs. 1403.22 Section 1403.22 Food and....22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1)...

  6. 36 CFR 1207.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Allowable costs. 1207.22... GOVERNMENTS Post-Award Requirements Financial Administration § 1207.22 Allowable costs. (a) Limitation on...

  7. 45 CFR 1183.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... than a hospital and an organization named in OBM Circular A-122 as not subject to that circular 48 CFR... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 1183.22 Section 1183.22 Public....22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1)...

  8. 7 CFR 3016.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... 7 Agriculture 15 2011-01-01 2011-01-01 false Allowable costs. 3016.22 Section 3016.22 Agriculture... GOVERNMENTS Post-Award Requirements Financial Administration § 3016.22 Allowable costs. (a) Limitation on...

  9. 20 CFR 633.303 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... otherwise indicated below, direct and indirect costs shall be charged in accordance with 41 CFR part 29-70... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Allowable costs. 633.303 Section 633.303... FARMWORKER PROGRAMS Program Design and Administrative Procedures § 633.303 Allowable costs. (a) General....

  10. 24 CFR 85.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Allowable costs. 85.22 Section 85... TRIBAL GOVERNMENTS Post-Award Requirements Financial Administration § 85.22 Allowable costs....

  11. 38 CFR 43.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Allowable costs. 43.22... Requirements Financial Administration § 43.22 Allowable costs. (a) Limitation on use of funds. Grant funds...

  12. 45 CFR 602.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 602.22 Section 602.22 Public... Requirements § 602.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for:...

  13. 29 CFR 1470.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting... 29 Labor 4 2010-07-01 2010-07-01 false Allowable costs. 1470.22 Section 1470.22 Labor Regulations... Financial Administration § 1470.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be...

  14. 45 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... determined in accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31... 45 Public Welfare 1 2011-10-01 2011-10-01 false Allowable costs. 74.27 Section 74.27 Public... Allowable costs. (a) For each kind of recipient, there is a particular set of Federal principles...

  15. 45 CFR 1174.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... than a hospital and an organization named in OBM Circular A-122 as not subject to that circular 48 CFR... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 1174.22 Section 1174.22 Public....22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1)...

  16. 2 CFR 215.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CFR part 230, “Cost Principles for Non-Profit Organizations (OMB Circular A-122).” The allowability of... CFR part 220, “Cost Principles for Educational Institutions (OMB Circular A-21).” The allowability of costs incurred by hospitals is determined in accordance with the provisions of appendix E of 45 CFR...

  17. 24 CFR 85.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Allowable costs. 85.22 Section 85... TRIBAL GOVERNMENTS Post-Award Requirements Financial Administration § 85.22 Allowable costs....

  18. 45 CFR 2541.220 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... not subject to that circular 48 CFR Part 31. Contract Cost Principles and Procedures, or uniform cost... 45 Public Welfare 4 2010-10-01 2010-10-01 false Allowable costs. 2541.220 Section 2541.220 Public... Post-Award Requirements § 2541.220 Allowable costs. (a) Limitation on use of funds. Grant funds may...

  19. 45 CFR 92.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... to that circular 48 CFR Part 31. Contract Cost Principles and Procedures, or uniform cost accounting... 45 Public Welfare 1 2011-10-01 2011-10-01 false Allowable costs. 92.22 Section 92.22 Public... Financial Administration § 92.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be...

  20. 10 CFR 600.317 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Organizations.” (iii) Hospitals. Allowability is determined in accordance with the provisions of 45 CFR part 74... OMB Circular A-122 is determined in accordance with the for-profit costs principles in 48 CFR part 31... Contracts with Hospitals.” (iv) Governmental organizations. Allowability for State, local, or...

  1. 33 CFR 136.211 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.211 Compensation allowable. (a) The amount of compensation allowable is the reasonable cost of assessing damages, and...

  2. 21 CFR 1303.24 - Inventory allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Inventory allowance. 1303.24 Section 1303.24 Food... Quotas § 1303.24 Inventory allowance. (a) For the purpose of determining individual manufacturing quotas... sufficient to maintain an inventory equal to, (1) For current manufacturers, 50 percent of his...

  3. 10 CFR 600.127 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall... incurred by hospitals is determined in accordance with the provisions of Appendix E of 45 CFR part 74... Federal Acquisition Regulation (FAR) at 48 CFR part 31. (b) Indirect costs. Unless restricted by...

  4. 10 CFR 600.127 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall... incurred by hospitals is determined in accordance with the provisions of Appendix E of 45 CFR part 74... Federal Acquisition Regulation (FAR) at 48 CFR part 31. (b) Indirect costs. Unless restricted by...

  5. 10 CFR 600.127 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall... incurred by hospitals is determined in accordance with the provisions of Appendix E of 45 CFR part 74... Federal Acquisition Regulation (FAR) at 48 CFR part 31. (b) Indirect costs. Unless restricted by...

  6. 10 CFR 600.127 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall... incurred by hospitals is determined in accordance with the provisions of Appendix E of 45 CFR part 74... Federal Acquisition Regulation (FAR) at 48 CFR part 31. (b) Indirect costs. Unless restricted by...

  7. 75 FR 4098 - Utility Allowance Adjustments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-26

    ... URBAN DEVELOPMENT Utility Allowance Adjustments AGENCY: Office of the Chief Information Officer, HUD... are required to advise the Secretary of the need for and request of a new utility allowance for... whether the information will have practical utility; (2) Evaluate the accuracy of the agency's estimate...

  8. 32 CFR 32.27 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... of allowable costs that are in accordance with uniform cost accounting standards and comply with cost... NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 32.27 Allowable... contractors is determined in accordance with the provisions of Appendix E to 45 CFR part 74, “Principles...

  9. 28 CFR 70.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 70.27 Allowable costs. (a... bids, proposals, and applications. Bid and proposal costs of the current accounting period are all allowable as indirect costs. Bid and proposal costs of past accounting periods are unallowable in...

  10. 32 CFR 32.27 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... of allowable costs that are in accordance with uniform cost accounting standards and comply with cost... NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 32.27 Allowable... contractors is determined in accordance with the provisions of Appendix E to 45 CFR part 74, “Principles...

  11. 28 CFR 70.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 70.27 Allowable costs. (a... bids, proposals, and applications. Bid and proposal costs of the current accounting period are all allowable as indirect costs. Bid and proposal costs of past accounting periods are unallowable in...

  12. 28 CFR 70.27 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 70.27 Allowable costs. (a... bids, proposals, and applications. Bid and proposal costs of the current accounting period are all allowable as indirect costs. Bid and proposal costs of past accounting periods are unallowable in...

  13. 32 CFR 32.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... of allowable costs that are in accordance with uniform cost accounting standards and comply with cost... NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 32.27 Allowable... contractors is determined in accordance with the provisions of Appendix E to 45 CFR part 74, “Principles...

  14. 30 CFR 1206.160 - Operating allowances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Operating allowances. 1206.160 Section 1206.160 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.160 Operating allowances. Notwithstanding any...

  15. 30 CFR 1206.160 - Operating allowances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Operating allowances. 1206.160 Section 1206.160 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.160 Operating allowances. Notwithstanding any...

  16. 30 CFR 1206.160 - Operating allowances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Operating allowances. 1206.160 Section 1206.160 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.160 Operating allowances. Notwithstanding any...

  17. The Role of Allowances in Adolescent Socialization.

    ERIC Educational Resources Information Center

    Miller, Joanne; Yung, Susan

    1990-01-01

    Examines high school student perceptions of allowances and the conditions under which they are received. Finds that, contrary to adult conceptions, students perceive allowances as an entitlement or earned income rather than as an educational opportunity promoting financial decision making and money management. (FMW)

  18. 45 CFR 602.22 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION UNIFORM...) The allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to...

  19. 45 CFR 602.22 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION UNIFORM...) The allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to...

  20. 45 CFR 602.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION UNIFORM...) The allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to...

  1. 40 CFR 30.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 30.27 Allowable..., “Cost Principles for State and Local Governments.” The allowability of costs incurred by non-profit... organizations and those non-profit organizations listed in Attachment C to Circular A-122 is determined...

  2. 38 CFR 49.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial and Program Management § 49.27 Allowable... for State, Local, and Indian Tribal Governments.” The allowability of costs incurred by non-profit... organizations and those non-profit organizations listed in Attachment C to Circular A-122 is determined...

  3. Family allowances and fertility: socioeconomic differences.

    PubMed

    Schellekens, Jona

    2009-08-01

    This article explores socioeconomic differences in the effect of family allowances on fertility. Although several studies have examined the relationship between cash benefits and fertility, few studies have addressed the possible differential effects of cash benefits on families of different income or education levels. I reconstructed the birth histories of women in the past two Israeli censuses of 1983 and 1995 to study socioeconomic differences in the effect of family allowances up to the seventh parity. The results indicate that family allowances have a significant effect at every parity. Using female education as an indicator of socioeconomic status, I find that socioeconomic status is a significant modifier of the effect of family allowances. Family allowances seem to have a relatively large impact on more-educated women.

  4. Modeling of crack initiation, intensity, and growth rates from flaws in welded steel structures

    NASA Astrophysics Data System (ADS)

    Thaxton, Eric Alan

    2000-10-01

    The intent of this dissertation is to develop a method to model the effects of pitting corrosion or mechanical damage on the strength and fatigue life of a welded structure. The problem was first examined when pitting corrosion was discovered in a 5,200 gallon capacity pressure vessel at John F. Kennedy Space Center. Other similar corrosion and mechanical damage is often encountered in service and a general method to model internal defects and crack-like flaws in welded structures is needed. The severity of the defect was modeled by finite element methods. Defect intensity and crack growth rate are both modeled using the finite element method developed here. Existing published solutions and fracture mechanics testing was performed to verify the modeling method. Welded structures such as pressure vessels have a metallurgical discontinuity between the parent metal and the heat affected zone and also between the heat-affected zone and the weld filler material. An added complexity is the fact that, in general, the mechanical and fracture mechanics properties of these three zones are different. The welded area also will have some level of residual stress resulting from the differential cooling and solidification after welding. The residual stresses created by solidification and cooling will be incorporated into the finite element model. The results will be checked by measuring the actual stresses on the test specimen. The unique contribution of this research is a finite element based tool, which provides a numerically efficient method to evaluate strength, resistance to fracture, and remaining life of a welded structure with surface damage. The new method is based on the theoretical square root displacement field, fitted to the local nodal point displacements, in the vicinity of the crack front. A linear finite element formulation is utilized, along with relatively coarse meshes, to accurately predict stress intensities. This new method is accurate for both two and

  5. 45 CFR 34.4 - Allowable claims.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... occurred. (7) Claims for automobiles, only when required to perform official business or parked on a... amount allowed is the value of the vehicle at the time of loss as determined by the National...

  6. 38 CFR 3.810 - Clothing allowance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... a wheelchair) because of such disability and such disability is the loss or loss of use of a hand or... wheelchair. (b) Effective August 1, 1972, the initial lump sum clothing allowance is due and payable...

  7. 38 CFR 3.810 - Clothing allowance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... a wheelchair) because of such disability and such disability is the loss or loss of use of a hand or... wheelchair. (b) Effective August 1, 1972, the initial lump sum clothing allowance is due and payable...

  8. Higher Education Tax Allowances: An Analysis

    ERIC Educational Resources Information Center

    Leslie, Larry L.

    1976-01-01

    Tax allowances are receiving renewed attention at the federal level. Various forms are evaluated that would aid middle-income students and private institutions, and specific bills and proposals are examined. (Editor/LBH)

  9. Assessment of strength limiting flaws in ceramic heat exchanger components: Phase 1, Final report, September 28, 1984-June 30, 1986

    SciTech Connect

    Powers, T.; Snyder, J.

    1986-10-01

    Assurance of energy efficient design lifetimes of high temperature structural ceramics requires the ability to specify acceptance criteria and to test to those criteria. These criteria will be established through nondestructive testing, to determine which defects are detectable, together with fracture mechanics, to calculate effects of indetectable flaws. The first phase of this program is to examine heat exchanger material with four test methods which have shown promise for use in ceramics; ultrasonic scanning, microfocus x-ray, Scanning Laser Acoustic Microscope, and Acoustic Holography. The capabilities, limits, and potential for improvement of these are presented in this report. Destructive testing, material sectioning, and fractography are included. 24 refs., 68 figs., 6 tabs.

  10. Crack-closure and crack-growth measurements in surface-flawed titanium alloy Ti6Al-4V

    NASA Technical Reports Server (NTRS)

    Elber, W.

    1975-01-01

    The crack-closure and crack-growth characteristics of the titanium alloy Ti-6Al-4V were determined experimentally on surface-flawed plate specimens. Under cyclic loading from zero to tension, cracks deeper than 1 mm opened at approximately 50 percent of the maximum load. Cracks shallower than 1 mm opened at higher loads. The correlation between crack-growth rate and the total stress-intensity range showed a lower threshold behavior. This behavior was attributed to the high crack-opening loads at short cracks because the lower threshold was much less evident in correlations between the crack-growth rates and the effective stress-intensity range.

  11. 15 CFR 24.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... than a hospital and an organization named in OBM Circular A-122 as not subject to that circular 48 CFR... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Allowable costs. 24.22 Section 24.22... Administration § 24.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1)...

  12. Regulatory treatment of allowances and compliance costs

    SciTech Connect

    Rose, K.

    1993-07-01

    The Clean Air Act Amendments of 1990 (CAAA) established a national emission allowance trading system, a market-based form of environmental regulation designed to reduce and limit sulfur dioxide emissions. However, the allowance trading system is being applied primarily to an economically regulated electric utility industry. The combining of the new form of environmental regulation and economic regulation of electric utilities has raised a number of questions including what the role should be of the federal and state utility regulating commissions and how those actions will affect the decision making process of the utilities and the allowance market. There are several dimensions to the regulatory problems that commissions face. Allowances and utility compliance expenditures have implications for least-cost/IPR (integrated resource planning), prudence review procedures, holding company and multistate utility regulation and ratemaking treatment. The focus of this paper is on the ratemaking treatment. The following topics are covered: ratemaking treatment of allowances and compliance costs; Traditional cost-recovery mechanisms; limitations to the traditional approach; traditional approach and the allowance trading market; market-based cost recovery mechanisms; methods of determining the benchmark; determining the split between ratepayers and the utility; other regulatory approaches; limitations of incentive mechanisms.

  13. Quantum theory allows for absolute maximal contextuality

    NASA Astrophysics Data System (ADS)

    Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adán

    2015-12-01

    Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number α and the Tsirelson-like number ϑ of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for absolute maximal contextuality if it has scenarios in which ϑ /α approaches n . Here we show that quantum theory allows for absolute maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-absolute-maximal contextuality.

  14. Using EPA`s allowance tracking system to assess the allowance market

    SciTech Connect

    Dean, M.; Kruger, J.

    1997-12-31

    The development of a credible framework for analyzing private allowance transfers recorded in EPA`s Allowance Tracking System (ATS) is essential for effective assessment of the sulfur dioxide (SO{sub 2}) allowance market. The ATS began recording transfers of allowances in March, 1994, and since then has served as an automated record of allowance holdings and transfers of ownership. Though primarily concerned with determining compliance, the ATS contains details of private allowance transfers representing what is believed to be a significant portion of overall SO{sub 2} allowance market activity. This paper will analyze these private transfers recorded in ATS and will develop relevant categories for classification purposes. The resulting categorization will enable consistent analysis of the SO{sub 2} allowance market and provide substantial insight into the level and type of allowance trading activity under the Acid Rain Program.

  15. Calculation of Weibull strength parameters, Batdorf flaw density constants and related statistical quantities using PC-CARES

    NASA Technical Reports Server (NTRS)

    Szatmary, Steven A.; Gyekenyesi, John P.; Nemeth, Noel N.

    1990-01-01

    This manual describes the operation and theory of the PC-CARES (Personal Computer-Ceramic Analysis and Reliability Evaluation of Structures) computer program for the IBM PC and compatibles running PC-DOS/MS-DOR OR IBM/MS-OS/2 (version 1.1 or higher) operating systems. The primary purpose of this code is to estimate Weibull material strength parameters, the Batdorf crack density coefficient, and other related statistical quantities. Included in the manual is the description of the calculation of shape and scale parameters of the two-parameter Weibull distribution using the least-squares analysis and maximum likelihood methods for volume- and surface-flaw-induced fracture in ceramics with complete and censored samples. The methods for detecting outliers and for calculating the Kolmogorov-Smirnov and the Anderson-Darling goodness-of-fit statistics and 90 percent confidence bands about the Weibull line, as well as the techniques for calculating the Batdorf flaw-density constants are also described.

  16. 44 CFR 208.41 - Administrative allowance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Administrative allowance. 208.41 Section 208.41 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE NATIONAL URBAN SEARCH AND RESCUE RESPONSE SYSTEM Response Cooperative Agreements § 208.41...

  17. 7 CFR 3016.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to cost-type contractors but not any fee or profit (or...

  18. 49 CFR 18.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... named in OBM Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and... of the grantees, subgrantees and cost-type contractors, including allowable costs in the form of payments to fixed-price contractors; and (2) Reasonable fees or profit to cost-type contractors but not...

  19. Manpower Training Allowances: Financial Assistance or Investment?

    ERIC Educational Resources Information Center

    Latour, Georges

    1975-01-01

    The author compares the differing approaches of Germany, Sweden, France, and Australia for providing financial support to adults enrolled in vocational training programs, focusing on training allowances for recurrent education. He concludes that without some governmental maintenance program, it is unlikely that adults can utilize even tuition-free…

  20. 24 CFR 84.27 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Allowable costs. 84.27 Section 84.27 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER...

  1. 24 CFR 84.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Allowable costs. 84.27 Section 84.27 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER...

  2. 24 CFR 84.27 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Allowable costs. 84.27 Section 84.27 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER...

  3. 32 CFR 33.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply with cost principles acceptable to the Federal agency. ... allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind of...

  4. 32 CFR 32.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contractors is determined in accordance with the provisions of Appendix E to 45 CFR part 74, “Principles for... contractor receiving a. cost-type contract under an assistance award, there is a set of Federal principles... principles applicable to the entity incurring the costs. (b) Governmental organizations. Allowability...

  5. 40 CFR 258.74 - Allowable mechanisms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... located in the United States amounting to at least the sum of current closure, post-closure care... MUNICIPAL SOLID WASTE LANDFILLS Financial Assurance Criteria § 258.74 Allowable mechanisms. The mechanisms... and examined by a Federal or State agency. A copy of the trust agreement must be placed in...

  6. 40 CFR 258.74 - Allowable mechanisms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... located in the United States amounting to at least the sum of current closure, post-closure care... MUNICIPAL SOLID WASTE LANDFILLS Financial Assurance Criteria § 258.74 Allowable mechanisms. The mechanisms... and examined by a Federal or State agency. A copy of the trust agreement must be placed in...

  7. 40 CFR 258.74 - Allowable mechanisms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... located in the United States amounting to at least the sum of current closure, post-closure care... MUNICIPAL SOLID WASTE LANDFILLS Financial Assurance Criteria § 258.74 Allowable mechanisms. The mechanisms... and examined by a Federal or State agency. A copy of the trust agreement must be placed in...

  8. 42 CFR 405.2468 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Allowable costs. 405.2468 Section 405.2468 Public... FEDERAL HEALTH INSURANCE FOR THE AGED AND DISABLED Rural Health Clinic and Federally Qualified Health... 413 of this subchapter. (b) Typical rural health clinic and Federally qualified health center...

  9. 33 CFR 136.217 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.217 Section 136.217 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  10. 33 CFR 136.235 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.235 Section 136.235 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  11. 33 CFR 136.223 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.223 Section 136.223 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  12. 33 CFR 136.211 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.211 Section 136.211 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  13. 33 CFR 136.205 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.205 Section 136.205 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  14. 33 CFR 136.229 - Compensation allowable.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Compensation allowable. 136.229 Section 136.229 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND;...

  15. 29 CFR 15.22 - Allowable claims.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... service with the Department and: (l) The damage or loss was not caused wholly or partly by the negligent... the other provisions of this subpart, any claim for damage to, or loss, of personal property incident... authorized places. Claims may be allowable for damage to, or loss of, property arising from fire,...

  16. 33 CFR 136.241 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.241...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.241...

  17. 33 CFR 136.217 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.217...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.217...

  18. 33 CFR 136.205 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.205...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.205...

  19. 33 CFR 136.223 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.223...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.223...

  20. 33 CFR 136.235 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.235...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.235...

  1. 33 CFR 136.229 - Compensation allowable.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.229...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.229...

  2. 29 CFR 15.41 - Allowable claims.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... if the claim is cognizable under the Federal Tort Claims Act (28 U.S.C. 2677). (c) A claim for damage... Secretary of Labor ADMINISTRATIVE CLAIMS UNDER THE FEDERAL TORT CLAIMS ACT AND RELATED STATUTES Claims Arising Out of the Operation of the Job Corps § 15.41 Allowable claims. (a)(1) A claim for damage...

  3. 14 CFR 1260.127 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Allowable costs. 1260.127 Section 1260.127 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS Uniform Administrative Requirements for Grants and Cooperative Agreements With Institutions of Higher...

  4. 14 CFR 1260.127 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Allowable costs. 1260.127 Section 1260.127 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS Uniform Administrative Requirements for Grants and Cooperative Agreements With Institutions of Higher...

  5. 14 CFR 1260.127 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Allowable costs. 1260.127 Section 1260.127 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS Uniform Administrative Requirements for Grants and Cooperative Agreements With Institutions of Higher...

  6. 14 CFR 1260.127 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Allowable costs. 1260.127 Section 1260.127 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GRANTS AND COOPERATIVE AGREEMENTS Uniform Administrative Requirements for Grants and Cooperative Agreements With Institutions of Higher...

  7. 21 CFR 1403.22 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 9 2014-04-01 2014-04-01 false Allowable costs. 1403.22 Section 1403.22 Food and... COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 1403... the applicable cost principles. For the costs of a— Use the principles in— State, local or...

  8. 21 CFR 1403.22 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Allowable costs. 1403.22 Section 1403.22 Food and... COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 1403... the applicable cost principles. For the costs of a— Use the principles in— State, local or...

  9. 21 CFR 1403.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Allowable costs. 1403.22 Section 1403.22 Food and... COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 1403... the applicable cost principles. For the costs of a— Use the principles in— State, local or...

  10. 21 CFR 1403.22 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 9 2013-04-01 2013-04-01 false Allowable costs. 1403.22 Section 1403.22 Food and... COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 1403... the applicable cost principles. For the costs of a— Use the principles in— State, local or...

  11. 38 CFR 21.5822 - Subsistence allowance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR Sections Affected, which appears in the Finding Aids section of the printed volume and on GPO... will make payments of subsistence allowance on the first day of the month following the month for which... enrollment certification so late that payment cannot be made on the first day of the month following...

  12. Allowance trading: Market operations and regulatory response

    SciTech Connect

    Bailey, K.A.; South, D.W.; McDermott, K.A.

    1992-12-31

    The use of the SO{sub 2} allowance system as defined by Title IV of the 1990 Clean Air Act Amendments offers utilities greater compliance flexibility than EPA technology standards, State Implementation Plan (SEP) performance standards, or EPA bubble/offset strategies. Traditional methods at best offered the utility the ability to trade emissions between different units at a particular plant. The SO{sub 2} emissions trading system advocated under Title IV will allow a utility to trade emissions across its utility system, and/or trade emissions between utilities to take advantage of interfirm control cost differences. The use of transferable emission allowances offers utilities greater flexibility in the choice of how to control emissions: the choices include fuel switching, flue gas scrubbing, environmental dispatch, repowering, and even the choice not to control emissions [as long as the New Source Performance Standards (NSPS) and Prevention of Significant Deterioration (PSD) requirements are met]. The added flexibility allows utilities to choose the least cost manner of compliance with Title IV requirements. It is hoped (intended) that pollution control cost-minimization by individual utilities will in turn reduce the cost of controlling SO{sub 2} for the electric utility industry in aggregate. In addition, through the use of NO{sub x} emission averaging, the utility would average NO{sub x} emissions from different point sources in order to comply with the prescribed emission standard.

  13. 40 CFR 30.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Allowable costs. 30.27 Section 30.27 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE UNIFORM...-recognized Indian tribal governments is determined in accordance with the provisions of OMB Circular...

  14. 40 CFR 30.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Allowable costs. 30.27 Section 30.27 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE UNIFORM...-recognized Indian tribal governments is determined in accordance with the provisions of OMB Circular...

  15. 40 CFR 30.27 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Allowable costs. 30.27 Section 30.27 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE UNIFORM...-recognized Indian tribal governments is determined in accordance with the provisions of OMB Circular...

  16. 40 CFR 30.27 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Allowable costs. 30.27 Section 30.27 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE UNIFORM...-recognized Indian tribal governments is determined in accordance with the provisions of OMB Circular...

  17. Allowance trading: Market operations and regulatory response

    SciTech Connect

    Bailey, K.A.; South, D.W.; McDermott, K.A.

    1992-01-01

    The use of the SO[sub 2] allowance system as defined by Title IV of the 1990 Clean Air Act Amendments offers utilities greater compliance flexibility than EPA technology standards, State Implementation Plan (SEP) performance standards, or EPA bubble/offset strategies. Traditional methods at best offered the utility the ability to trade emissions between different units at a particular plant. The SO[sub 2] emissions trading system advocated under Title IV will allow a utility to trade emissions across its utility system, and/or trade emissions between utilities to take advantage of interfirm control cost differences. The use of transferable emission allowances offers utilities greater flexibility in the choice of how to control emissions: the choices include fuel switching, flue gas scrubbing, environmental dispatch, repowering, and even the choice not to control emissions [as long as the New Source Performance Standards (NSPS) and Prevention of Significant Deterioration (PSD) requirements are met]. The added flexibility allows utilities to choose the least cost manner of compliance with Title IV requirements. It is hoped (intended) that pollution control cost-minimization by individual utilities will in turn reduce the cost of controlling SO[sub 2] for the electric utility industry in aggregate. In addition, through the use of NO[sub x] emission averaging, the utility would average NO[sub x] emissions from different point sources in order to comply with the prescribed emission standard.

  18. 30 CFR 1220.012 - Overhead allowance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Overhead allowance. 1220.012 Section 1220.012 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES... under § 1220.011(c) that are salvaged, returned, or used for the benefit of non-NPSL operations....

  19. 30 CFR 1220.012 - Overhead allowance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Overhead allowance. 1220.012 Section 1220.012 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES... under § 1220.011(c) that are salvaged, returned, or used for the benefit of non-NPSL operations....

  20. 30 CFR 1220.012 - Overhead allowance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Overhead allowance. 1220.012 Section 1220.012 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES... under § 1220.011(c) that are salvaged, returned, or used for the benefit of non-NPSL operations....

  1. 30 CFR 1220.012 - Overhead allowance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Overhead allowance. 1220.012 Section 1220.012 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR Natural Resources Revenue ACCOUNTING PROCEDURES FOR DETERMINING NET PROFIT SHARE PAYMENT FOR OUTER CONTINENTAL...

  2. 30 CFR 220.012 - Overhead allowance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Overhead allowance. 220.012 Section 220.012 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT ACCOUNTING PROCEDURES FOR DETERMINING NET PROFIT SHARE PAYMENT FOR OUTER CONTINENTAL SHELF OIL AND GAS...

  3. 14 CFR 1273.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... principles applicable to the organization incurring the costs. The following chart lists the kinds of... CFR part 31, Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Allowable costs. 1273.22 Section...

  4. 21 CFR 1315.24 - Inventory allowance.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 9 2013-04-01 2013-04-01 false Inventory allowance. 1315.24 Section 1315.24 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE IMPORTATION AND PRODUCTION QUOTAS FOR EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE Individual Manufacturing Quotas § 1315.24...

  5. 21 CFR 1315.24 - Inventory allowance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Inventory allowance. 1315.24 Section 1315.24 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE IMPORTATION AND PRODUCTION QUOTAS FOR EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE Individual Manufacturing Quotas § 1315.24...

  6. 21 CFR 1315.24 - Inventory allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Inventory allowance. 1315.24 Section 1315.24 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE IMPORTATION AND PRODUCTION QUOTAS FOR EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE Individual Manufacturing Quotas § 1315.24...

  7. 21 CFR 1315.24 - Inventory allowance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 9 2014-04-01 2014-04-01 false Inventory allowance. 1315.24 Section 1315.24 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE IMPORTATION AND PRODUCTION QUOTAS FOR EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE Individual Manufacturing Quotas § 1315.24...

  8. 21 CFR 1315.24 - Inventory allowance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Inventory allowance. 1315.24 Section 1315.24 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE IMPORTATION AND PRODUCTION QUOTAS FOR EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE Individual Manufacturing Quotas § 1315.24...

  9. 32 CFR 34.17 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... prime awards from DoD Components, and those that are subrecipients under prime awards to other organizations, is to be determined in accordance with: (1) The for-profit cost principles in 48 CFR parts 31 and.... (3) Hospitals. Allowability is determined in accordance with the provisions of 45 CFR part...

  10. 32 CFR 34.17 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... prime awards from DoD Components, and those that are subrecipients under prime awards to other organizations, is to be determined in accordance with: (1) The for-profit cost principles in 48 CFR parts 31 and.... (3) Hospitals. Allowability is determined in accordance with the provisions of 45 CFR part...

  11. 10 CFR 600.127 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Local Governments.” The allowability of costs incurred by non-profit organizations is determined in accordance with the provisions of OMB Circular A-122, “Cost Principles for Non-Profit Organizations.” The... incurred by hospitals is determined in accordance with the provisions of Appendix E of 45 CFR part...

  12. 44 CFR 13.22 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Allowable costs. 13.22... HOMELAND SECURITY GENERAL UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS...

  13. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... STANDARDS AND CORRECTIVE ACTION REQUIREMENTS FOR OWNERS AND OPERATORS OF UNDERGROUND STORAGE TANKS (UST) General Operating Requirements § 280.33 Repairs allowed. Owners and operators of UST systems must ensure... operating properly. (f) UST system owners and operators must maintain records of each repair for...

  14. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... STANDARDS AND CORRECTIVE ACTION REQUIREMENTS FOR OWNERS AND OPERATORS OF UNDERGROUND STORAGE TANKS (UST) General Operating Requirements § 280.33 Repairs allowed. Owners and operators of UST systems must ensure... operating properly. (f) UST system owners and operators must maintain records of each repair for...

  15. 15 CFR 14.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CFR part 74, “Principles for Determining Costs Applicable to Research and Development Under Grants and... provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Allowable costs. 14.27 Section...

  16. 20 CFR 632.37 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... otherwise indicated below, direct and indirect costs shall be charged in accordance with 41 CFR 29-70 and 41 CFR 1-15.7. (c) Costs associated with repairs, maintenance, and capital improvements of existing... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Allowable costs. 632.37 Section...

  17. 38 CFR 49.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... of Appendix E of 45 CFR part 74, “Principles for Determining Costs Applicable to Research and... accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. (Authority: Pub... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Allowable costs....

  18. 7 CFR 3019.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the provisions of Appendix E of 45 CFR part 74, “Principles for Determining Costs Applicable to... determined in accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. ... 7 Agriculture 15 2011-01-01 2011-01-01 false Allowable costs. 3019.27 Section 3019.27...

  19. 36 CFR 1210.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the provisions of Appendix E of 45 CFR Part 74, “Principles for Determining Costs Applicable to... the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR Part 31. ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Allowable costs....

  20. 45 CFR 2543.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CFR part 74, “Principles for Determining Costs Applicable to Research and Development Under Grants and... provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Allowable costs. 2543.27 Section 2543.27...

  1. 24 CFR 84.27 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of Appendix E of 45 CFR part 74, “Principles for Determining Costs Applicable to Research and... accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Allowable costs. 84.27 Section...

  2. 24 CFR 84.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of Appendix E of 45 CFR part 74, “Principles for Determining Costs Applicable to Research and... accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part 31. ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Allowable costs. 84.27 Section...

  3. 43 CFR 12.62 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Circular A-122 as not subject to that circular 48 CFR Part 31. Contract Cost Principles and Procedures, or... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Allowable costs. 12.62 Section 12.62... COST PRINCIPLES FOR ASSISTANCE PROGRAMS Uniform Administrative Requirements for Grants and...

  4. 10 CFR 440.18 - Allowable expenditures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the purchase of vehicles or other certain types of equipment as defined in 10 CFR part 600 may be... 10 Energy 3 2010-01-01 2010-01-01 false Allowable expenditures. 440.18 Section 440.18 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION WEATHERIZATION ASSISTANCE FOR LOW-INCOME PERSONS § 440.18...

  5. 10 CFR 440.18 - Allowable expenditures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the purchase of vehicles or other certain types of equipment as defined in 10 CFR part 600 may be... 10 Energy 3 2014-01-01 2014-01-01 false Allowable expenditures. 440.18 Section 440.18 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION WEATHERIZATION ASSISTANCE FOR LOW-INCOME PERSONS § 440.18...

  6. 10 CFR 440.18 - Allowable expenditures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the purchase of vehicles or other certain types of equipment as defined in 10 CFR part 600 may be... 10 Energy 3 2012-01-01 2012-01-01 false Allowable expenditures. 440.18 Section 440.18 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION WEATHERIZATION ASSISTANCE FOR LOW-INCOME PERSONS § 440.18...

  7. 38 CFR 3.810 - Clothing allowance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... prosthetic or orthopedic appliance (including, but not limited to, a wheelchair) which tends to wear or tear... appliance (including, but not limited to, a wheelchair) which tends to wear or tear clothing; or (B) A... allowance for each prosthetic or orthopedic appliance (including, but not limited to, a wheelchair)...

  8. 38 CFR 3.810 - Clothing allowance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... prosthetic or orthopedic appliance (including, but not limited to, a wheelchair) which tends to wear or tear... appliance (including, but not limited to, a wheelchair) which tends to wear or tear clothing; or (B) A... allowance for each prosthetic or orthopedic appliance (including, but not limited to, a wheelchair)...

  9. 5 CFR 180.104 - Allowable claims.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Allowable claims. 180.104 Section 180.104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS EMPLOYEES' PERSONAL PROPERTY... are payable: (i) Where personal funds were accepted by responsible Government personnel with...

  10. Family allowance and family planning in Chile.

    PubMed Central

    Plank, S J

    1978-01-01

    Family allowances designed to promote maternal and child health and welfare could be self-defeating if they stimulated otherwise unwanted births, as often assumed. That assumption, with its public health and demographic implications, needs testing. An attempt to test it was made in Chile in 1969--1970 through interviews with 945 wives receiving an allowance and 690 non-recipients. Recipients practiced contraception significantly more than did non-recipients. This was not explained by wives' educational attainment or employment, the couples' earnings, or number of living children, but was associated with a 50 per cent greater utilization of professional prenatal care by recipients during the most recent pregnancy; women with such care (regardless of allowance status) were 75 per cent more likely than others to control their fertility. Prenatal care was probably sought more by recipients in part because an additional stipend was provided as soon as pregnancy was confirmed, usually at clinics with integrated family planning. Greater family income, attributable to the allowance, probably also contributed to the recipients' better prenatal attention and to contraceptive practice. Noteworthy, too, was the finding that with the number of living children controlled, contraceptive practice was significantly greater amoung couples who had never lost a child. PMID:717610

  11. 29 CFR 15.22 - Allowable claims.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Department and: (l) The damage or loss was not caused wholly or partly by the negligent or wrongful act or... subpart, any claim for damage to, or loss, of personal property incident to service with the Department... excluded: (1) Property or damage in quarters or other authorized places. Claims may be allowable for...

  12. 45 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... costs of the current accounting period are allowable as indirect costs. Bid and proposal costs of past..., AND COMMERCIAL ORGANIZATIONS Post-Award Requirements Financial and Program Management § 74.27... determined in accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part...

  13. 45 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... costs of the current accounting period are allowable as indirect costs. Bid and proposal costs of past..., AND COMMERCIAL ORGANIZATIONS Post-Award Requirements Financial and Program Management § 74.27... determined in accordance with the provisions of the Federal Acquisition Regulation (FAR) at 48 CFR part...

  14. 44 CFR 13.22 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Allowable costs. 13.22... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply with cost principles acceptable to the Federal agency....

  15. 44 CFR 13.22 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Allowable costs. 13.22... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply with cost principles acceptable to the Federal agency....

  16. 34 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Program Management § 74.27 Allowable costs. (a) For each kind of recipient, there is a set of cost... organization other than a hospital and an educational institution 48 CFR part 31 Contract Cost Principles and Procedures or uniform cost accounting standards that comply with cost principles acceptable to ED. (b)...

  17. 34 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Program Management § 74.27 Allowable costs. (a) For each kind of recipient, there is a set of cost... organization other than a hospital and an educational institution 48 CFR part 31 Contract Cost Principles and Procedures or uniform cost accounting standards that comply with cost principles acceptable to ED. (b)...

  18. 34 CFR 74.27 - Allowable costs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Program Management § 74.27 Allowable costs. (a) For each kind of recipient, there is a set of cost... organization other than a hospital and an educational institution 48 CFR part 31 Contract Cost Principles and Procedures or uniform cost accounting standards that comply with cost principles acceptable to ED. (b)...

  19. 44 CFR 13.22 - Allowable costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Allowable costs. 13.22... Circular A-122 as not subject to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply with cost principles acceptable to the Federal agency....

  20. 15 CFR 14.27 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, OTHER NON-PROFIT, AND COMMERCIAL..., Local and Indian Tribal Governments.” The allowability of costs incurred by non-profit organizations is determined in accordance with the provisions of OMB Circular A-122, “Cost Principles for...

  1. 34 CFR 675.33 - Allowable costs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Allowable costs. 675.33 Section 675.33 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION FEDERAL WORK-STUDY PROGRAMS Job Location and Development Program § 675.33...

  2. 45 CFR 34.4 - Allowable claims.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CIVILIAN EMPLOYEES ACT § 34.4 Allowable claims. (a) What you can claim. (1) Claims for damage or loss may... for property damage or loss by fire, flood, hurricane, theft, or other serious occurrence may be... a civilian employee outside the U.S. is a local inhabitant. (3) Claims for damage to, or loss...

  3. 20 CFR 617.47 - Moving allowance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... pounds net weight authorized under the Federal travel regulations (see 41 CFR part 101-7) by commercial..., against loss or damage in transit, if a bid from a licensed insurer is obtained by the individual and... allowable costs shall be: (A) If the trailer is hauled by private vehicle, the cost per mile for the use...

  4. 5 CFR 180.104 - Allowable claims.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... for which the claim is made. For example, borrowed property may be the subject of a claim. (c) Subject... the claimant is a local inhabitant; or (iii) Any warehouse, office, working area, or other place... Government other than OPM. (11) Borrowed property. Claims may be allowed for borrowed property that has...

  5. 76 FR 32340 - Federal Travel Regulation; Temporary Duty (TDY) Travel Allowances (Taxes); Relocation Allowances...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-06

    ... Duty (TDY) Travel Allowances (Taxes); Relocation Allowances (Taxes) AGENCY: Office of Governmentwide... Relocation Advisory Board (GRAB) concerning calculation of reimbursements for taxes on relocation expenses. In addition, this proposed rule alters the process for calculating reimbursements for taxes...

  6. 78 FR 26637 - Federal Travel Regulation (FTR); Relocation Allowance-Relocation Income Tax (RIT) Allowable Tables

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-07

    ... ADMINISTRATION Federal Travel Regulation (FTR); Relocation Allowance--Relocation Income Tax (RIT) Allowable Tables AGENCY: Office of Governmentwide Policy (OGP), General Services Administration (GSA). ACTION... June 25, 2008 (73 FR 35952), specifying that GSA would no longer publish the RIT Allowance tables...

  7. Biannual birth pulses allow filoviruses to persist in bat populations.

    PubMed

    Hayman, David T S

    2015-03-22

    Filoviruses Ebolavirus (EBOV) and Marburgvirus (MARV) cause haemorrhagic fevers with high mortality rates, posing significant threats to public health. To understand transmission into human populations, filovirus dynamics within reservoir host populations must be understood. Studies have directly linked filoviruses to bats, but the mechanisms allowing viral persistence within bat populations are poorly understood. Theory suggests seasonal birthing may decrease the probability of pathogen persistence within populations, but data suggest MARV may persist within colonies of seasonally breeding Egyptian fruit bats, Rousettus aegyptiacus. I synthesize available filovirus and bat data in a stochastic compartmental model to explore fundamental questions relating to filovirus ecology: can filoviruses persist within isolated bat colonies; do critical community sizes exist; and how do host-pathogen relationships affect spillover transmission potential? Synchronous annual breeding and shorter incubation periods did not allow filovirus persistence, whereas bi-annual breeding and longer incubation periods, such as reported for Egyptian fruit bats and EBOV in experimental studies, allowed persistence in colony sizes often found in nature. Serological data support the findings, with bats from species with two annual birth pulses more likely to be seropositive (odds ratio (OR) 4.4, 95% confidence interval (CI) 2.5-8.7) than those with one, suggesting that biannual birthing is necessary for filovirus persistence. PMID:25673678

  8. Biannual birth pulses allow filoviruses to persist in bat populations

    PubMed Central

    Hayman, David T. S.

    2015-01-01

    Filoviruses Ebolavirus (EBOV) and Marburgvirus (MARV) cause haemorrhagic fevers with high mortality rates, posing significant threats to public health. To understand transmission into human populations, filovirus dynamics within reservoir host populations must be understood. Studies have directly linked filoviruses to bats, but the mechanisms allowing viral persistence within bat populations are poorly understood. Theory suggests seasonal birthing may decrease the probability of pathogen persistence within populations, but data suggest MARV may persist within colonies of seasonally breeding Egyptian fruit bats, Rousettus aegyptiacus. I synthesize available filovirus and bat data in a stochastic compartmental model to explore fundamental questions relating to filovirus ecology: can filoviruses persist within isolated bat colonies; do critical community sizes exist; and how do host–pathogen relationships affect spillover transmission potential? Synchronous annual breeding and shorter incubation periods did not allow filovirus persistence, whereas bi-annual breeding and longer incubation periods, such as reported for Egyptian fruit bats and EBOV in experimental studies, allowed persistence in colony sizes often found in nature. Serological data support the findings, with bats from species with two annual birth pulses more likely to be seropositive (odds ratio (OR) 4.4, 95% confidence interval (CI) 2.5–8.7) than those with one, suggesting that biannual birthing is necessary for filovirus persistence. PMID:25673678

  9. Evaluation of the Maximum Allowable Cost Program

    PubMed Central

    Lee, A. James; Hefner, Dennis; Dobson, Allen; Hardy, Ralph

    1983-01-01

    This article summarizes an evaluation of the Maximum Allowable Cost (MAC)-Estimated Acquisition Cost (EAC) program, the Federal Government's cost-containment program for prescription drugs.1 The MAC-EAC regulations which became effective on August 26, 1976, have four major components: (1) Maximum Allowable Cost reimbursement limits for selected multisource or generically available drugs; (2) Estimated Acquisition Cost reimbursement limits for all drugs; (3) “usual and customary” reimbursement limits for all drugs; and (4) a directive that professional fee studies be performed by each State. The study examines the benefits and costs of the MAC reimbursement limits for 15 dosage forms of five multisource drugs and EAC reimbursement limits for all drugs for five selected States as of 1979. PMID:10309857

  10. Detection and Sizing of Fatigue Cracks in Steel Welds with Advanced Eddy Current Techniques

    NASA Astrophysics Data System (ADS)

    Todorov, E. I.; Mohr, W. C.; Lozev, M. G.

    2008-02-01

    Butt-welded specimens were fatigued to produce cracks in the weld heat-affected zone. Advanced eddy current (AEC) techniques were used to detect and size the cracks through a coating. AEC results were compared with magnetic particle and phased-array ultrasonic techniques. Validation through destructive crack measurements was also conducted. Factors such as geometry, surface treatment, and crack tightness interfered with depth sizing. AEC inspection techniques have the potential of providing more accurate and complete sizing flaw data for manufacturing and in-service inspections.

  11. Robust technique allowing manufacturing superoleophobic surfaces

    NASA Astrophysics Data System (ADS)

    Bormashenko, Edward; Grynyov, Roman; Chaniel, Gilad; Taitelbaum, Haim; Bormashenko, Yelena

    2013-04-01

    We report the robust technique allowing manufacturing of superhydrophobic and oleophobic (omniphobic) surfaces with industrial grade low density polyethylene. The reported process includes two stages: (1) hot embossing of polyethylene with micro-scaled steel gauzes; (2) treatment of embossed surfaces with cold radiofrequency plasma of tetrafluoromethane. The reported surfaces demonstrate not only pronounced superhydrophobicity but also superoleophobicity. Superoleophobicity results from the hierarchical nano-scaled topography of fluorinated polyethylene surface. The observed superoleophobicity is strengthened by the hydrophobic recovery. The stability of the Cassie wetting regime was studied.

  12. Coalescent simulation in continuous space: algorithms for large neighbourhood size.

    PubMed

    Kelleher, J; Etheridge, A M; Barton, N H

    2014-08-01

    Many species have an essentially continuous distribution in space, in which there are no natural divisions between randomly mating subpopulations. Yet, the standard approach to modelling these populations is to impose an arbitrary grid of demes, adjusting deme sizes and migration rates in an attempt to capture the important features of the population. Such indirect methods are required because of the failure of the classical models of isolation by distance, which have been shown to have major technical flaws. A recently introduced model of extinction and recolonisation in two dimensions solves these technical problems, and provides a rigorous technical foundation for the study of populations evolving in a spatial continuum. The coalescent process for this model is simply stated, but direct simulation is very inefficient for large neighbourhood sizes. We present efficient and exact algorithms to simulate this coalescent process for arbitrary sample sizes and numbers of loci, and analyse these algorithms in detail. PMID:24910324

  13. Flaws in current human training protocols for spontaneous Brain-Computer Interfaces: lessons learned from instructional design

    PubMed Central

    Lotte, Fabien; Larrue, Florian; Mühl, Christian

    2013-01-01

    While recent research on Brain-Computer Interfaces (BCI) has highlighted their potential for many applications, they remain barely used outside laboratories. The main reason is their lack of robustness. Indeed, with current BCI, mental state recognition is usually slow and often incorrect. Spontaneous BCI (i.e., mental imagery-based BCI) often rely on mutual learning efforts by the user and the machine, with BCI users learning to produce stable ElectroEncephaloGraphy (EEG) patterns (spontaneous BCI control being widely acknowledged as a skill) while the computer learns to automatically recognize these EEG patterns, using signal processing. Most research so far was focused on signal processing, mostly neglecting the human in the loop. However, how well the user masters the BCI skill is also a key element explaining BCI robustness. Indeed, if the user is not able to produce stable and distinct EEG patterns, then no signal processing algorithm would be able to recognize them. Unfortunately, despite the importance of BCI training protocols, they have been scarcely studied so far, and used mostly unchanged for years. In this paper, we advocate that current human training approaches for spontaneous BCI are most likely inappropriate. We notably study instructional design literature in order to identify the key requirements and guidelines for a successful training procedure that promotes a good and efficient skill learning. This literature study highlights that current spontaneous BCI user training procedures satisfy very few of these requirements and hence are likely to be suboptimal. We therefore identify the flaws in BCI training protocols according to instructional design principles, at several levels: in the instructions provided to the user, in the tasks he/she has to perform, and in the feedback provided. For each level, we propose new research directions that are theoretically expected to address some of these flaws and to help users learn the BCI skill more

  14. Flaws in current human training protocols for spontaneous Brain-Computer Interfaces: lessons learned from instructional design.

    PubMed

    Lotte, Fabien; Larrue, Florian; Mühl, Christian

    2013-01-01

    While recent research on Brain-Computer Interfaces (BCI) has highlighted their potential for many applications, they remain barely used outside laboratories. The main reason is their lack of robustness. Indeed, with current BCI, mental state recognition is usually slow and often incorrect. Spontaneous BCI (i.e., mental imagery-based BCI) often rely on mutual learning efforts by the user and the machine, with BCI users learning to produce stable ElectroEncephaloGraphy (EEG) patterns (spontaneous BCI control being widely acknowledged as a skill) while the computer learns to automatically recognize these EEG patterns, using signal processing. Most research so far was focused on signal processing, mostly neglecting the human in the loop. However, how well the user masters the BCI skill is also a key element explaining BCI robustness. Indeed, if the user is not able to produce stable and distinct EEG patterns, then no signal processing algorithm would be able to recognize them. Unfortunately, despite the importance of BCI training protocols, they have been scarcely studied so far, and used mostly unchanged for years. In this paper, we advocate that current human training approaches for spontaneous BCI are most likely inappropriate. We notably study instructional design literature in order to identify the key requirements and guidelines for a successful training procedure that promotes a good and efficient skill learning. This literature study highlights that current spontaneous BCI user training procedures satisfy very few of these requirements and hence are likely to be suboptimal. We therefore identify the flaws in BCI training protocols according to instructional design principles, at several levels: in the instructions provided to the user, in the tasks he/she has to perform, and in the feedback provided. For each level, we propose new research directions that are theoretically expected to address some of these flaws and to help users learn the BCI skill more

  15. Slimhole advancements allow economic offshore exploitation

    SciTech Connect

    Shanks, E.

    1995-07-01

    Slimhole drilling technology is a proven method to reduce well cost in remote areas of the world. It also provides advantages in offshore drilling and production applications where smaller tubular sizes can make marginal fields economic. The technological accomplishments within the industry have provided a sound basis to apply slimhole technology offshore worldwide. And it is feasible to develop methods to apply this technology to more sever applications, including deeper wells, high-pressure wells and hole problem areas, such as troublesome shales. Such applications will require additional technology development to be adequately prepared for proper well designs and possible contingencies during drilling. From the experience to date with this technology, it is feasible to design wells to total drilled depths of 12,000 ft--15,000 ft onshore or offshore. For purposes of this article, a slimhole well is one with the diameter at TD less than 6-in.

  16. 76 FR 16629 - Federal Travel Regulation (FTR); Relocation Allowances-Relocation Income Tax Allowance (RITA) Tables

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-24

    ... ADMINISTRATION Federal Travel Regulation (FTR); Relocation Allowances-- Relocation Income Tax Allowance (RITA... transferee's increased tax burden due to an employee's official permanent change of station is now available... Register (73 FR 35952) specifying that the General Services Administration (GSA) would no longer...

  17. 75 FR 14442 - Federal Travel Regulation (FTR); Relocation Allowances-Relocation Income Tax Allowance (RITA) Tables

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... ADMINISTRATION Federal Travel Regulation (FTR); Relocation Allowances-- Relocation Income Tax Allowance (RITA... Amendment 2008-04 in the Federal Register (73 FR 35952) specifying that GSA would no longer publish the RITA... 16, 2010 and applies to relocations during tax year 2008 and earlier. FOR FURTHER INFORMATION...

  18. 42 CFR 61.9 - Payments: Stipends; dependency allowances; travel allowances.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Payments: Stipends; dependency allowances; travel allowances. 61.9 Section 61.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.9 Payments: Stipends;...

  19. 42 CFR 61.9 - Payments: Stipends; dependency allowances; travel allowances.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Payments: Stipends; dependency allowances; travel allowances. 61.9 Section 61.9 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.9 Payments: Stipends;...

  20. 42 CFR 61.8 - Benefits: Stipends; dependency allowances; travel allowances; vacation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Benefits: Stipends; dependency allowances; travel allowances; vacation. 61.8 Section 61.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.8 Benefits:...