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Sample records for cutting plane algorithm

  1. A Deep-Cutting-Plane Technique for Reverse Convex Optimization.

    PubMed

    Moshirvaziri, K; Amouzegar, M A

    2011-08-01

    A large number of problems in engineering design and in many areas of social and physical sciences and technology lend themselves to particular instances of problems studied in this paper. Cutting-plane methods have traditionally been used as an effective tool in devising exact algorithms for solving convex and large-scale combinatorial optimization problems. Its utilization in nonconvex optimization has been also promising. A cutting plane, essentially a hyperplane defined by a linear inequality, can be used to effectively reduce the computational efforts in search of a global solution. Each cut is generated in order to eliminate a large portion of the search domain. Thus, a deep cut is intuitively superior in which it will exclude a larger set of extraneous points from consideration. This paper is concerned with the development of deep-cutting-plane techniques applied to reverse-convex programs. An upper bound and a lower bound for the optimal value are found, updated, and improved at each iteration. The algorithm terminates when the two bounds collapse or all the generated subdivisions have been fathomed. Finally, computational considerations and numerical results on a set of test problems are discussed. An illustrative example, walking through the steps of the algorithm and explaining the computational process, is presented. PMID:21296710

  2. Displaying CFD Solution Parameters on Arbitrary Cut Planes

    NASA Technical Reports Server (NTRS)

    Pao, S. Paul

    2008-01-01

    USMC6 is a Fortran 90 computer program for post-processing in support of visualization of flows simulated by computational fluid dynamics (CFD). The name "USMC6" is partly an abbreviation of "TetrUSS - USM3D Solution Cutter," reflecting its origin as a post-processor for use with USM3D - a CFD program that is a component of the Tetrahedral Unstructured Software System and that solves the Navier-Stokes equations on tetrahedral unstructured grids. "Cutter" here refers to a capability to acquire and process solution data on (1) arbitrary planes that cut through grid volumes, or (2) user-selected spheroidal, conical, cylindrical, and/or prismatic domains cut from within grids. Cutting saves time by enabling concentration of post-processing and visualization efforts on smaller solution domains of interest. The user can select from among more than 40 flow functions. The cut planes can be trimmed to circular or rectangular shape. The user specifies cuts and functions in a free-format input file using simple and easy-to-remember keywords. The USMC6 command line is simple enough that the slicing process can readily be embedded in a shell script for assembly-line post-processing. The output of USMC6 is a data file ready for plotting.

  3. Finite pure integer programming algorithms employing only hyperspherically deduced cuts

    NASA Technical Reports Server (NTRS)

    Young, R. D.

    1971-01-01

    Three algorithms are developed that may be based exclusively on hyperspherically deduced cuts. The algorithms only apply, therefore, to problems structured so that these cuts are valid. The algorithms are shown to be finite.

  4. Multiresolution Techniques for Interactive Texture-Based Rendering of Arbitrarily Oriented Cutting Planes

    SciTech Connect

    LaMar, E; Duchaineau, M A; Hamann, B; Joy, K I

    2001-10-03

    We present a multiresolution technique for interactive texture based rendering of arbitrarily oriented cutting planes for very large data sets. This method uses an adaptive scheme that renders the data along a cutting plane at different resolutions: higher resolution near the point-of-interest and lower resolution away from the point-of-interest. The algorithm is based on the segmentation of texture space into an octree, where the leaves of the tree define the original data and the internal nodes define lower-resolution versions. Rendering is done adaptively by selecting high-resolution cells close to a center of attention and low-resolution cells away from it. We limit the artifacts introduced by this method by blending between different levels of resolution to produce a smooth image. This technique can be used to produce viewpoint-dependent renderings.

  5. Parametric integer linear programming: a synthesis of branch and bound with cutting planes

    SciTech Connect

    Rountree, S.L.K.; Gillett, B.E.

    1980-01-01

    A branch and bound algorithm is designed to solve the general integer linear programing problem with parametric right-hand sides. The right-hand sides have the form b + THETA d, where b and d are conformable vectors, d consists of nonegative constants, and THETA varies from zero to one. The method consists of first determining all possible right-hand side ineger constants and appending this set of integer constants to the initial tableau to form an expanded problem with a finite number of family members. The implicit enumeration method gives a lower bound on the integer solutions. The branch and bound method is used with fathoming tests that allow one family member possibly to fathom other family members. A cutting plane option applies a finite number of cuts to each node before branching. In addition, the cutting plane method is invoked whenever some members are feasible at a node and others are infeasible. The branching and cutting process is repeated until the entire family of problems has been solved. 3 tables.

  6. Improved branch-cut method algorithm applied in phase unwrapping

    NASA Astrophysics Data System (ADS)

    Hu, Jiayuan; Zhang, Yu; Wu, Jianle; Li, Jinlong; Wang, Haiqing

    2015-12-01

    Phase unwrapping is a common problem in many phase measuring techniques. Glodstein's branch-cut algorithm is one of classic ways of phase unwrapping, but it need rectifying. First the paper introduces the characteristics of residual points and describes Glodstein's branch-cut algorithm in detail. Then the paper discusses the improvements on the algorithm by changing branch setting and adding pretreatment. Last the paper summarizes the new algorithm and gets the better result by using computer emulation mode and validation test.

  7. An FMS Dynamic Production Scheduling Algorithm Considering Cutting Tool Failure and Cutting Tool Life

    NASA Astrophysics Data System (ADS)

    Setiawan, A.; Wangsaputra, R.; Martawirya, Y. Y.; Halim, A. H.

    2016-02-01

    This paper deals with Flexible Manufacturing System (FMS) production rescheduling due to unavailability of cutting tools caused either of cutting tool failure or life time limit. The FMS consists of parallel identical machines integrated with an automatic material handling system and it runs fully automatically. Each machine has a same cutting tool configuration that consists of different geometrical cutting tool types on each tool magazine. The job usually takes two stages. Each stage has sequential operations allocated to machines considering the cutting tool life. In the real situation, the cutting tool can fail before the cutting tool life is reached. The objective in this paper is to develop a dynamic scheduling algorithm when a cutting tool is broken during unmanned and a rescheduling needed. The algorithm consists of four steps. The first step is generating initial schedule, the second step is determination the cutting tool failure time, the third step is determination of system status at cutting tool failure time and the fourth step is the rescheduling for unfinished jobs. The approaches to solve the problem are complete-reactive scheduling and robust-proactive scheduling. The new schedules result differences starting time and completion time of each operations from the initial schedule.

  8. iCut: an Integrative Cut Algorithm Enables Accurate Segmentation of Touching Cells

    PubMed Central

    He, Yong; Gong, Hui; Xiong, Benyi; Xu, Xiaofeng; Li, Anan; Jiang, Tao; Sun, Qingtao; Wang, Simin; Luo, Qingming; Chen, Shangbin

    2015-01-01

    Individual cells play essential roles in the biological processes of the brain. The number of neurons changes during both normal development and disease progression. High-resolution imaging has made it possible to directly count cells. However, the automatic and precise segmentation of touching cells continues to be a major challenge for massive and highly complex datasets. Thus, an integrative cut (iCut) algorithm, which combines information regarding spatial location and intervening and concave contours with the established normalized cut, has been developed. iCut involves two key steps: (1) a weighting matrix is first constructed with the abovementioned information regarding the touching cells and (2) a normalized cut algorithm that uses the weighting matrix is implemented to separate the touching cells into isolated cells. This novel algorithm was evaluated using two types of data: the open SIMCEP benchmark dataset and our micro-optical imaging dataset from a Nissl-stained mouse brain. It has achieved a promising recall/precision of 91.2 ± 2.1%/94.1 ± 1.8% and 86.8 ± 4.1%/87.5 ± 5.7%, respectively, for the two datasets. As quantified using the harmonic mean of recall and precision, the accuracy of iCut is higher than that of some state-of-the-art algorithms. The better performance of this fully automated algorithm can benefit studies of brain cytoarchitecture. PMID:26168908

  9. Numerical modelling of orthogonal cutting: application to woodworking with a bench plane.

    PubMed

    Nairn, John A

    2016-06-01

    A numerical model for orthogonal cutting using the material point method was applied to woodcutting using a bench plane. The cutting process was modelled by accounting for surface energy associated with wood fracture toughness for crack growth parallel to the grain. By using damping to deal with dynamic crack propagation and modelling all contact between wood and the plane, simulations could initiate chip formation and proceed into steady-state chip propagation including chip curling. Once steady-state conditions were achieved, the cutting forces became constant and could be determined as a function of various simulation variables. The modelling details included a cutting tool, the tool's rake and grinding angles, a chip breaker, a base plate and a mouth opening between the base plate and the tool. The wood was modelled as an anisotropic elastic-plastic material. The simulations were verified by comparison to an analytical model and then used to conduct virtual experiments on wood planing. The virtual experiments showed interactions between depth of cut, chip breaker location and mouth opening. Additional simulations investigated the role of tool grinding angle, tool sharpness and friction. PMID:27274800

  10. Branch-cut algorithm for optical phase unwrapping.

    PubMed

    de Souza, J C; Oliveira, M E; dos Santos, P A M

    2015-08-01

    In this Letter, a proposal addressing the problem of two-dimensional phase unwrapping based on the theory of residues is presented. Here, wrapped phase maps with shifted phase jumps are used to balance residue charges. With this approach, we seek to minimize processing time and residue connection, which is essential in the development of branch-cut algorithms. Finally, a phase-unwrapping algorithm is applied to these wrapped maps, generated by Fourier transform profilometry to obtain three-dimensional profiles of objects illuminated by photorefractive moiré-like patterns generated in an experiment of real-time dynamic holography, and by fringe patterns generated with a Michelson interferometer. PMID:26258331

  11. Normalized Cut Algorithm for Automated Assignment of Protein Domains

    NASA Technical Reports Server (NTRS)

    Samanta, M. P.; Liang, S.; Zha, H.; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We present a novel computational method for automatic assignment of protein domains from structural data. At the core of our algorithm lies a recently proposed clustering technique that has been very successful for image-partitioning applications. This grap.,l-theory based clustering method uses the notion of a normalized cut to partition. an undirected graph into its strongly-connected components. Computer implementation of our method tested on the standard comparison set of proteins from the literature shows a high success rate (84%), better than most existing alternative In addition, several other features of our algorithm, such as reliance on few adjustable parameters, linear run-time with respect to the size of the protein and reduced complexity compared to other graph-theory based algorithms, would make it an attractive tool for structural biologists.

  12. A Cutting Surface Algorithm for Semi-Infinite Convex Programming with an Application to Moment Robust Optimization

    SciTech Connect

    Mehrotra, Sanjay; Papp, Dávid

    2014-01-01

    We present and analyze a central cutting surface algorithm for general semi-infinite convex optimization problems and use it to develop a novel algorithm for distributionally robust optimization problems in which the uncertainty set consists of probability distributions with given bounds on their moments. Moments of arbitrary order, as well as nonpolynomial moments, can be included in the formulation. We show that this gives rise to a hierarchy of optimization problems with decreasing levels of risk-aversion, with classic robust optimization at one end of the spectrum and stochastic programming at the other. Although our primary motivation is to solve distributionally robust optimization problems with moment uncertainty, the cutting surface method for general semi-infinite convex programs is also of independent interest. The proposed method is applicable to problems with nondifferentiable semi-infinite constraints indexed by an infinite dimensional index set. Examples comparing the cutting surface algorithm to the central cutting plane algorithm of Kortanek and No demonstrate the potential of our algorithm even in the solution of traditional semi-infinite convex programming problems, whose constraints are differentiable, and are indexed by an index set of low dimension. After the rate of convergence analysis of the cutting surface algorithm, we extend the authors' moment matching scenario generation algorithm to a probabilistic algorithm that finds optimal probability distributions subject to moment constraints. The combination of this distribution optimization method and the central cutting surface algorithm yields a solution to a family of distributionally robust optimization problems that are considerably more general than the ones proposed to date.

  13. A Cutting Surface Algorithm for Semi-Infinite Convex Programming with an Application to Moment Robust Optimization

    DOE PAGESBeta

    Mehrotra, Sanjay; Papp, Dávid

    2014-01-01

    We present and analyze a central cutting surface algorithm for general semi-infinite convex optimization problems and use it to develop a novel algorithm for distributionally robust optimization problems in which the uncertainty set consists of probability distributions with given bounds on their moments. Moments of arbitrary order, as well as nonpolynomial moments, can be included in the formulation. We show that this gives rise to a hierarchy of optimization problems with decreasing levels of risk-aversion, with classic robust optimization at one end of the spectrum and stochastic programming at the other. Although our primary motivation is to solve distributionally robustmore » optimization problems with moment uncertainty, the cutting surface method for general semi-infinite convex programs is also of independent interest. The proposed method is applicable to problems with nondifferentiable semi-infinite constraints indexed by an infinite dimensional index set. Examples comparing the cutting surface algorithm to the central cutting plane algorithm of Kortanek and No demonstrate the potential of our algorithm even in the solution of traditional semi-infinite convex programming problems, whose constraints are differentiable, and are indexed by an index set of low dimension. After the rate of convergence analysis of the cutting surface algorithm, we extend the authors' moment matching scenario generation algorithm to a probabilistic algorithm that finds optimal probability distributions subject to moment constraints. The combination of this distribution optimization method and the central cutting surface algorithm yields a solution to a family of distributionally robust optimization problems that are considerably more general than the ones proposed to date.« less

  14. Joint graph cut and relative fuzzy connectedness image segmentation algorithm.

    PubMed

    Ciesielski, Krzysztof Chris; Miranda, Paulo A V; Falcão, Alexandre X; Udupa, Jayaram K

    2013-12-01

    We introduce an image segmentation algorithm, called GC(sum)(max), which combines, in novel manner, the strengths of two popular algorithms: Relative Fuzzy Connectedness (RFC) and (standard) Graph Cut (GC). We show, both theoretically and experimentally, that GC(sum)(max) preserves robustness of RFC with respect to the seed choice (thus, avoiding "shrinking problem" of GC), while keeping GC's stronger control over the problem of "leaking though poorly defined boundary segments." The analysis of GC(sum)(max) is greatly facilitated by our recent theoretical results that RFC can be described within the framework of Generalized GC (GGC) segmentation algorithms. In our implementation of GC(sum)(max) we use, as a subroutine, a version of RFC algorithm (based on Image Forest Transform) that runs (provably) in linear time with respect to the image size. This results in GC(sum)(max) running in a time close to linear. Experimental comparison of GC(sum)(max) to GC, an iterative version of RFC (IRFC), and power watershed (PW), based on a variety medical and non-medical images, indicates superior accuracy performance of GC(sum)(max) over these other methods, resulting in a rank ordering of GC(sum)(max)>PW∼IRFC>GC. PMID:23880374

  15. W-band waveguide bandpass filter with E-plane cut.

    PubMed

    Furtula, Vedran; Salewski, Mirko

    2014-07-01

    In this paper, we present a design and measurements of a five-section bandpass filter with a passband from 96 to 106 GHz. The insertion loss is less than 1.4 dB in the passband, and the rejection is better than 40 dB in the range from 115 to 142 GHz. We use transmission line coupling theory based on Tchebyscheff's synthesis in order to provide an initial guess for the geometrical parameters of the filter such as cavity lengths and coupling widths. The filter is manufactured from brass in two halves in the E-plane cut topology. The S-parameters of the filter are measured and compared with the simulations. The measured passband insertion loss is approximately 0.4 dB worse than in the simulation, and the measured passband width is approximately 3.4% narrower. The measured filter attenuation roll-off corresponds well to the simulation. We also compare our S-parameter measurements of the E-plane filter with corresponding measurements of a very similar H-plane filter. The transmission and reflection characteristics of the E-plane filter are better than those of the H-plane filter. PMID:25085158

  16. Crossover Cutting During Hamstring Fatigue Produces Transverse Plane Knee Control Deficits

    PubMed Central

    Nyland, John A.; Caborn, David N.M.; Shapiro, Robert; Johnson, Darren L.

    1999-01-01

    Objective: To assess the effects of eccentric work-induced hamstring fatigue on sagittal and transverse plane (axial) knee and ankle biodynamics and kinetics during a running crossover cut directional change (functional pivot shift). Design and Setting: A pretest-posttest, single-group intervention experimental design was employed. All data were collected in a biodynamics laboratory. Subjects: Twenty healthy athletic females were trained for 3 weeks in crossover cutting before testing. Measurements: Data were sampled during 3 unfatigued and 3 fatigued (20% eccentric isokinetic knee-flexor torque reduction) crossover cut trials. Three-dimensional kinematic and ground reaction-force data were sampled at 200 Hz and 1000 Hz, respectively, and joint moment estimates were calculated. Data were standardized to initial force-plate heelstrike for comparisons of mean differences between conditions using paired t tests with Bonferroni adjustments. Pearson product-moment correlations compared kinematic and eccentric hamstring-torque relationships. Results: During internal rotation phase 1, between heelstrike and impact absorption, mean internal rotation velocity increased by 21.2°/s ± 114°/s. During internal rotation phase II, mean peak transverse plane knee rotation during propulsion decreased by 3.1° ± 9°. During internal rotation phase II, mean peak ankle plantar flexor moment onsets occurred 12.7 ± 53 milliseconds earlier, and this activation demonstrated a moderately positive relationship with the onset of mean peak knee internal rotation during propulsion and a weak negative relationship with mean peak hamstring torque/lean body weight. Conclusions: The increased knee internal rotation velocity during phase I indicates transverse plane dynamic knee-control deficits during hamstring fatigue. Earlier peak ankle plantar-flexor moments and decreased internal rotation during phase II in the presence of hamstring fatigue may represent compensatory attempts at dynamic

  17. Researches Regarding The Circular Interpolation Algorithms At CNC Laser Cutting Machines

    NASA Astrophysics Data System (ADS)

    Tîrnovean, Mircea Sorin

    2015-09-01

    This paper presents an integrated simulation approach for studying the circular interpolation regime of CNC laser cutting machines. The circular interpolation algorithm is studied, taking into consideration the numerical character of the system. A simulation diagram, which is able to generate the kinematic inputs for the feed drives of the CNC laser cutting machine is also presented.

  18. A unifying graph-cut image segmentation framework: algorithms it encompasses and equivalences among them

    NASA Astrophysics Data System (ADS)

    Ciesielski, Krzysztof Chris; Udupa, Jayaram K.; Falcão, A. X.; Miranda, P. A. V.

    2012-02-01

    We present a general graph-cut segmentation framework GGC, in which the delineated objects returned by the algorithms optimize the energy functions associated with the lp norm, 1 <= p <= ∞. Two classes of well known algorithms belong to GGC: the standard graph cut GC (such as the min-cut/max-flow algorithm) and the relative fuzzy connectedness algorithms RFC (including iterative RFC, IRFC). The norm-based description of GGC provides more elegant and mathematically better recognized framework of our earlier results from [18, 19]. Moreover, it allows precise theoretical comparison of GGC representable algorithms with the algorithms discussed in a recent paper [22] (min-cut/max-flow graph cut, random walker, shortest path/geodesic, Voronoi diagram, power watershed/shortest path forest), which optimize, via lp norms, the intermediate segmentation step, the labeling of scene voxels, but for which the final object need not optimize the used lp energy function. Actually, the comparison of the GGC representable algorithms with that encompassed in the framework described in [22] constitutes the main contribution of this work.

  19. Simple Common Plane contact algorithm for explicit FE/FD methods

    SciTech Connect

    Vorobiev, O

    2006-12-18

    Common-plane (CP) algorithm is widely used in Discrete Element Method (DEM) to model contact forces between interacting particles or blocks. A new simple contact algorithm is proposed to model contacts in FE/FD methods which is similar to the CP algorithm. The CP is defined as a plane separating interacting faces of FE/FD mesh instead of blocks or particles used in the original CP method. The new method does not require iterations even for very stiff contacts. It is very robust and easy to implement both in 2D and 3D parallel codes.

  20. Comparison of algorithms for out-of-plane artifacts removal in digital tomosynthesis reconstructions.

    PubMed

    Bliznakova, K; Bliznakov, Z; Buliev, I

    2012-07-01

    Digital tomosynthesis is a method of limited angle reconstruction of tomographic images produced at variable heights, on the basis of a set of angular projections taken in an arc around human anatomy. Reconstructed tomograms from unprocessed original projection images, however, are invariably affected by tomographic noise such as blurred images of objects lying outside the plane of interest and superimposed on the focused image of the fulcrum plane. The present work investigates the performance of two approaches for generation of tomograms with a reduced noise: a generalised post-processing method, based on constructing a noise mask from all planes in the reconstructed volume, and its subsequent subtraction from the in-focus plane and a filtered Multiple Projection Algorithm. The comparison between the two algorithms shows that the first method provides reconstructions with very good quality in case of high contrast features, especially for those embedded into a heterogeneous background. PMID:22056810

  1. Heuristic algorithms for solving of the tool routing problem for CNC cutting machines

    NASA Astrophysics Data System (ADS)

    Chentsov, P. A.; Petunin, A. A.; Sesekin, A. N.; Shipacheva, E. N.; Sholohov, A. E.

    2015-11-01

    The article is devoted to the problem of minimizing the path of the cutting tool to shape cutting machines began. This problem can be interpreted as a generalized traveling salesman problem. Earlier version of the dynamic programming method to solve this problem was developed. Unfortunately, this method allows to process an amount not exceeding thirty circuits. In this regard, the task of constructing quasi-optimal route becomes relevant. In this paper we propose options for quasi-optimal greedy algorithms. Comparison of the results of exact and approximate algorithms is given.

  2. Cutting Solid Figures by Plane--Analytical Solution and Spreadsheet Implementation

    ERIC Educational Resources Information Center

    Benacka, Jan

    2012-01-01

    In some secondary mathematics curricula, there is a topic called Stereometry that deals with investigating the position and finding the intersection, angle, and distance of lines and planes defined within a prism or pyramid. Coordinate system is not used. The metric tasks are solved using Pythagoras' theorem, trigonometric functions, and sine and…

  3. An adaptive guidance algorithm for an aerodynamically assisted orbital plane change maneuver. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Blissit, J. A.

    1986-01-01

    Using analysis results from the post trajectory optimization program, an adaptive guidance algorithm is developed to compensate for density, aerodynamic and thrust perturbations during an atmospheric orbital plane change maneuver. The maneuver offers increased mission flexibility along with potential fuel savings for future reentry vehicles. Although designed to guide a proposed NASA Entry Research Vehicle, the algorithm is sufficiently generic for a range of future entry vehicles. The plane change analysis provides insight suggesting a straight-forward algorithm based on an optimized nominal command profile. Bank angle, angle of attack, and engine thrust level, ignition and cutoff times are modulated to adjust the vehicle's trajectory to achieve the desired end-conditions. A performance evaluation of the scheme demonstrates a capability to guide to within 0.05 degrees of the desired plane change and five nautical miles of the desired apogee altitude while maintaining heating constraints. The algorithm is tested under off-nominal conditions of + or -30% density biases, two density profile models, + or -15% aerodynamic uncertainty, and a 33% thrust loss and for various combinations of these conditions.

  4. Reconstruction-plane-dependent weighted FDK algorithm for cone beam volumetric CT

    NASA Astrophysics Data System (ADS)

    Tang, Xiangyang; Hsieh, Jiang

    2005-04-01

    The original FDK algorithm has been extensively employed in medical and industrial imaging applications. With an increased cone angle, cone beam (CB) artifacts in images reconstructed by the original FDK algorithm deteriorate, since the circular trajectory does not satisfy the so-called data sufficiency condition (DSC). A few "circular plus" trajectories have been proposed in the past to reduce CB artifacts by meeting the DSC. However, the circular trajectory has distinct advantages over other scanning trajectories in practical CT imaging, such as cardiac, vascular and perfusion applications. In addition to looking into the DSC, another insight into the CB artifacts of the original FDK algorithm is the inconsistency between conjugate rays that are 180° apart in view angle. The inconsistence between conjugate rays is pixel dependent, i.e., it varies dramatically over pixels within the image plane to be reconstructed. However, the original FDK algorithm treats all conjugate rays equally, resulting in CB artifacts that can be avoided if appropriate view weighting strategy is exercised. In this paper, a modified FDK algorithm is proposed, along with an experimental evaluation and verification, in which the helical body phantom and a humanoid head phantom scanned by a volumetric CT (64 x 0.625 mm) are utilized. Without extra trajectories supplemental to the circular trajectory, the modified FDK algorithm applies reconstruction-plane-dependent view weighting on projection data before 3D backprojection, which reduces the inconsistency between conjugate rays by suppressing the contribution of one of the conjugate rays with a larger cone angle. Both computer-simulated and real phantom studies show that, up to a moderate cone angle, the CB artifacts can be substantially suppressed by the modified FDK algorithm, while advantages of the original FDK algorithm, such as the filtered backprojection algorithm structure, 1D ramp filtering, and data manipulation efficiency, can be

  5. Plane-based sampling for ray casting algorithm in sequential medical images.

    PubMed

    Lin, Lili; Chen, Shengyong; Shao, Yan; Gu, Zichun

    2013-01-01

    This paper proposes a plane-based sampling method to improve the traditional Ray Casting Algorithm (RCA) for the fast reconstruction of a three-dimensional biomedical model from sequential images. In the novel method, the optical properties of all sampling points depend on the intersection points when a ray travels through an equidistant parallel plan cluster of the volume dataset. The results show that the method improves the rendering speed at over three times compared with the conventional algorithm and the image quality is well guaranteed. PMID:23424608

  6. Robustness of ‘cut and splice’ genetic algorithms in the structural optimization of atomic clusters

    NASA Astrophysics Data System (ADS)

    Froltsov, Vladimir A.; Reuter, Karsten

    2009-05-01

    We return to the geometry optimization problem of Lennard-Jones clusters to analyze the performance dependence of 'cut and splice' genetic algorithms (GAs) on the employed population size. We generally find that admixing twinning mutation moves leads to an improved robustness of the algorithm efficiency with respect to this a priori unknown technical parameter. The resulting very stable performance of the corresponding mutation + mating GA implementation over a wide range of population sizes is an important feature when addressing unknown systems with computationally involved first-principles based GA sampling.

  7. Homogeneity improvement of N-polar (000\\bar{1}) InGaN/GaN multiple quantum wells by using c-plane sapphire substrate with off-cut-angle toward a-sapphire plane

    NASA Astrophysics Data System (ADS)

    Shojiki, Kanako; Hanada, Takashi; Tanikawa, Tomoyuki; Imai, Yasuhiko; Kimura, Shigeru; Nonoda, Ryohei; Kuboya, Shigeyuki; Katayama, Ryuji; Matsuoka, Takashi

    2016-05-01

    To improve the homogeneity of the N-polar (000\\bar{1}) (‑c-plane) InGaN/GaN multiple quantum wells (MQWs) grown by metalorganic vapor phase epitaxy (MOVPE), the growth of GaN and MQW on two c-plane sapphire substrates with an off-cut angle of 0.8° toward the a-plane (sub-A) and the m-plane (sub-M) was performed. The effects of the off-cut direction on the structural properties and surface morphologies of ‑c-plane GaN films were elucidated. It was found that the step bunching and meandering of ‑c-plane GaN were significantly suppressed on sub-A. The spatial homogeneity of the ‑c-plane InGaN/GaN MQWs along the off-cut direction was observed in the submicrometer scale using microbeam X-ray diffraction. By inhibiting the step bunching of the GaN template using sub-A, the thickness homogeneity of the MQWs on sub-A has been significantly improved in comparison with that on sub-M.

  8. Effect of r-plane (1-102) sapphire off-cut angle on the anisotropic strain in nonpolar Si-doped a-plane (11-20) GaN

    NASA Astrophysics Data System (ADS)

    Kim, Ji Hoon; Park, Jung Ho; Hwang, Sung-Min; Baik, Kwang Hyeon

    2012-05-01

    We studied the growth and the characteristics of nonpolar Si-doped a-plane GaN grown on r-plane sapphire substrates with different off-cut angles which were changed in the range of -0.2° ˜ +0.4°. Samples grown by using -0.2° and +0.2° off-cut angles showed triangular pit-free and smooth surfaces, which resulted from enhanced lateral growth owing to the epitaxial films having a Ga face. On the other hand, the sample grown by using +0.4° off-cut angles revealed a high density of pits and low crystalline quality due to a high density of dislocations. The strain determined by using calculations with the lattice parameters also showed a dependence on the off-cut angles. We expect r-plane sapphire with off-cut angles in the range of -0.2° ˜ +0.2° to be very effective for improving the crystalline quality and the surface morphology of a-plane GaN.

  9. Kidney segmentation in CT sequences using SKFCM and improved GrowCut algorithm

    PubMed Central

    2015-01-01

    Background Organ segmentation is an important step in computer-aided diagnosis and pathology detection. Accurate kidney segmentation in abdominal computed tomography (CT) sequences is an essential and crucial task for surgical planning and navigation in kidney tumor ablation. However, kidney segmentation in CT is a substantially challenging work because the intensity values of kidney parenchyma are similar to those of adjacent structures. Results In this paper, a coarse-to-fine method was applied to segment kidney from CT images, which consists two stages including rough segmentation and refined segmentation. The rough segmentation is based on a kernel fuzzy C-means algorithm with spatial information (SKFCM) algorithm and the refined segmentation is implemented with improved GrowCut (IGC) algorithm. The SKFCM algorithm introduces a kernel function and spatial constraint into fuzzy c-means clustering (FCM) algorithm. The IGC algorithm makes good use of the continuity of CT sequences in space which can automatically generate the seed labels and improve the efficiency of segmentation. The experimental results performed on the whole dataset of abdominal CT images have shown that the proposed method is accurate and efficient. The method provides a sensitivity of 95.46% with specificity of 99.82% and performs better than other related methods. Conclusions Our method achieves high accuracy in kidney segmentation and considerably reduces the time and labor required for contour delineation. In addition, the method can be expanded to 3D segmentation directly without modification. PMID:26356850

  10. Wide bandsaw blade under cutting conditions. Part I: Vibration of a plate moving in its plane while subjected to tangential edge loading

    NASA Astrophysics Data System (ADS)

    Lengoc, L.; McCallion, H.

    1995-09-01

    The cutting span of a bandsaw blade is modelled as a moving plate and a simple, yet powerful, method is presented for analyzing its vibration when subjected to various in-plane stresses, including stresses due to tangential cutting forces. Time-independent tangential edge-loading couples modes of vibration and can lead to divergent buckling. The effects of transport velocity, "back-crowning" and "prestressing" on the vibration of a moving plate under tangential cutting forces are also investigated. Graphical representations of the modes of vibration are presented.

  11. Bladder segmentation in MR images with watershed segmentation and graph cut algorithm

    NASA Astrophysics Data System (ADS)

    Blaffert, Thomas; Renisch, Steffen; Schadewaldt, Nicole; Schulz, Heinrich; Wiemker, Rafael

    2014-03-01

    Prostate and cervix cancer diagnosis and treatment planning that is based on MR images benefit from superior soft tissue contrast compared to CT images. For these images an automatic delineation of the prostate or cervix and the organs at risk such as the bladder is highly desirable. This paper describes a method for bladder segmentation that is based on a watershed transform on high image gradient values and gray value valleys together with the classification of watershed regions into bladder contents and tissue by a graph cut algorithm. The obtained results are superior if compared to a simple region-after-region classification.

  12. Vibration suppression in cutting tools using collocated piezoelectric sensors/actuators with an adaptive control algorithm

    SciTech Connect

    Radecki, Peter P; Farinholt, Kevin M; Park, Gyuhae; Bement, Matthew T

    2008-01-01

    The machining process is very important in many engineering applications. In high precision machining, surface finish is strongly correlated with vibrations and the dynamic interactions between the part and the cutting tool. Parameters affecting these vibrations and dynamic interactions, such as spindle speed, cut depth, feed rate, and the part's material properties can vary in real-time, resulting in unexpected or undesirable effects on the surface finish of the machining product. The focus of this research is the development of an improved machining process through the use of active vibration damping. The tool holder employs a high bandwidth piezoelectric actuator with an adaptive positive position feedback control algorithm for vibration and chatter suppression. In addition, instead of using external sensors, the proposed approach investigates the use of a collocated piezoelectric sensor for measuring the dynamic responses from machining processes. The performance of this method is evaluated by comparing the surface finishes obtained with active vibration control versus baseline uncontrolled cuts. Considerable improvement in surface finish (up to 50%) was observed for applications in modern day machining.

  13. Brain tumor segmentation in MR slices using improved GrowCut algorithm

    NASA Astrophysics Data System (ADS)

    Ji, Chunhong; Yu, Jinhua; Wang, Yuanyuan; Chen, Liang; Shi, Zhifeng; Mao, Ying

    2015-12-01

    The detection of brain tumor from MR images is very significant for medical diagnosis and treatment. However, the existing methods are mostly based on manual or semiautomatic segmentation which are awkward when dealing with a large amount of MR slices. In this paper, a new fully automatic method for the segmentation of brain tumors in MR slices is presented. Based on the hypothesis of the symmetric brain structure, the method improves the interactive GrowCut algorithm by further using the bounding box algorithm in the pre-processing step. More importantly, local reflectional symmetry is used to make up the deficiency of the bounding box method. After segmentation, 3D tumor image is reconstructed. We evaluate the accuracy of the proposed method on MR slices with synthetic tumors and actual clinical MR images. Result of the proposed method is compared with the actual position of simulated 3D tumor qualitatively and quantitatively. In addition, our automatic method produces equivalent performance as manual segmentation and the interactive GrowCut with manual interference while providing fully automatic segmentation.

  14. Gender Differences among Sagittal Plane Knee Kinematic and Ground Reaction Force Characteristics during a Rapid Sprint and Cut Maneuver

    ERIC Educational Resources Information Center

    James, C. Roger; Sizer, Phillip S.; Starch, David W.; Lockhart, Thurmon E.; Slauterbeck, James

    2004-01-01

    Women are more prone to anterior cruciate ligament (ACL) injury during cutting sports than men. The purpose of this study was to examine knee kinematic and ground reaction forces (GRF) differences between genders during cutting. Male and female athletes performed cutting trials while force platform and video data were recorded (180 Hz).…

  15. High-speed measurement algorithm for the position of holes in a large plane

    NASA Astrophysics Data System (ADS)

    Shi, Yongqiang; Sun, Changku; Wang, Peng; Wang, Zhong; Duan, Hongxu

    2012-12-01

    CMM is widely used to measure the position of the holes on the top surface of an engine block. However, CMM requires a perfect environment and cannot be applied in online measurements. Moreover, using CMM to measure the position of holes in a large plane takes more than 10 min, thus lowering its efficiency. To solve this problem, this paper presents a high-speed measurement algorithm for the position of holes in a large plane based on a flexible datum and the feature neighborhood model. First, two area CCD cameras that grab the images of the reference holes of the block are used to establish the flexible datum. Second, different mapping models are built in the neighborhood of the center of different holes. These black-box mapping models ignore the intermediate process of camera perspective projection. Finally, the feature points in the different scales of the neighborhood of the hole centers solve the mapping results. The mapping results are then weighted by using the multi-scale weighting algorithm. The calibration target is designed, but the feature points in the target are minimal. Thus, a new method to create several more feature points is designed. Compared with the measurement result of CMM, the maximum position error of the measurement system is 0.025 mm. The relative error is better than 0.025% and the standard deviation of the measurement data is less than 0.010 mm. With a conference level of 95%, the system measurement uncertainty is better than ±0.020 mm. The measuring time is less than 3 min. The position measurement scheme features high automation and high efficiency, and can be used in the position measurement of online engine block holes.

  16. A new efficient algorithm generating all minimal S-T cut-sets in a graph-modeled network

    NASA Astrophysics Data System (ADS)

    Malinowski, Jacek

    2016-06-01

    A new algorithm finding all minimal s-t cut-sets in a graph-modeled network with failing links and nodes is presented. It is based on the analysis of the tree of acyclic s-t paths connecting a given pair of nodes in the considered structure. The construction of such a tree is required by many existing algorithms for s-t cut-sets generation in order to eliminate "stub" edges or subgraphs through which no acyclic path passes. The algorithm operates on the acyclic paths tree alone, i.e. no other analysis of the network's topology is necessary. It can be applied to both directed and undirected graphs, as well as partly directed ones. It is worth noting that the cut-sets can be composed of both links and failures, while many known algorithms do not take nodes into account, which is quite restricting from the practical point of view. The developed cut-sets generation technique makes the algorithm significantly faster than most of the previous methods, as proved by the experiments.

  17. Embedded nonuniformity correction in infrared focal plane arrays using the Constant Range algorithm

    NASA Astrophysics Data System (ADS)

    Redlich, Rodolfo; Figueroa, Miguel; Torres, Sergio N.; Pezoa, Jorge E.

    2015-03-01

    We present a digital fixed-point architecture that performs real-time nonuniformity correction in infrared (IR) focal plane arrays using the Constant Range algorithm. The circuit estimates and compensates online the gains and offsets of a first-order nonuniformity model using pixel statistics from the video stream. We demonstrate our architecture with a prototype built on a Xilinx Spartan-6 XC6SLX45T field-programmable gate array (FPGA), which can process an IR video stream from a FLIR Tau 2 long-wave IR camera with a resolution of 640 × 480 14-bit pixels at up to 238 frames per second (fps) with low resource utilization and adds only 13 mW to the FPGA power. Post-layout simulations of a custom integrated circuit implementation of the architecture on a 32 nm CMOS process show that the circuit can operate at up to 900 fps at the same resolution, and consume less than 4.5 mW.

  18. An algorithm for the calculation of the partial wave expansion of the Coulomb-distorted plane wave

    NASA Astrophysics Data System (ADS)

    Hornyak, I.; Kruppa, A. T.

    2015-12-01

    The partial wave expansion of the Coulomb-distorted plane wave is determined by the help of the complex generalized hypergeometric function 2F2(a , a ; a + l + 1 , a - l ; z) . An algorithm for the calculation of 2F2(a , a ; a + l + 1 , a - l ; z) is created and it is implemented as a FORTRAN-90 code. The code is fast and its accuracy is 14 significant decimal digits.

  19. A semi-implicit finite strain shell algorithm using in-plane strains based on least-squares

    NASA Astrophysics Data System (ADS)

    Areias, P.; Rabczuk, T.; de Sá, J. César; Natal Jorge, R.

    2015-04-01

    The use of a semi-implicit algorithm at the constitutive level allows a robust and concise implementation of low-order effective shell elements. We perform a semi-implicit integration in the stress update algorithm for finite strain plasticity: rotation terms (highly nonlinear trigonometric functions) are integrated explicitly and correspond to a change in the (in this case evolving) reference configuration and relative Green-Lagrange strains (quadratic) are used to account for change in the equilibrium configuration implicitly. We parametrize both reference and equilibrium configurations, in contrast with the so-called objective stress integration algorithms which use a common configuration. A finite strain quadrilateral element with least-squares assumed in-plane shear strains (in curvilinear coordinates) and classical transverse shear assumed strains is introduced. It is an alternative to enhanced-assumed-strain (EAS) formulations and, contrary to this, produces an element satisfying ab-initio the Patch test. No additional degrees-of-freedom are present, contrasting with EAS. Least-squares fit allows the derivation of invariant finite strain elements which are both in-plane and out-of-plane shear-locking free and amenable to standardization in commercial codes. Two thickness parameters per node are adopted to reproduce the Poisson effect in bending. Metric components are fully deduced and exact linearization of the shell element is performed. Both isotropic and anisotropic behavior is presented in elasto-plastic and hyperelastic examples.

  20. Preparation of Y123 films on REAlO 3-buffered off-cut substrates of R-plane sapphire

    NASA Astrophysics Data System (ADS)

    Yamaguchi, I.; Manabe, T.; Sohma, M.; Tsuchiya, T.; Kumagai, T.; Suzuki, S.; Yamaguchi, Y.; Watanabe, T.; Mizuta, S.

    2002-10-01

    An epitaxial YBa 2Cu 3O 7- x (Y123) film was prepared on a REAlO 3 (RENd)-buffered vicinal (off-cut angle: 4.5°) α-Al 2O 3( 1¯ 0 1 2) substrate and their crystallographic relationship was investigated. Both the NdAlO 3-buffer layer and Y123 film were obtained by a coating-pyrolysis process. The XRD θ-2 θ scanning exhibited the growth of a/ c-oriented Y123. However, XRD ω-scanning of the Y123 006 reflection showed that the c-axis oriented grains comprised two components; the intensity ratio being >2:1. The c-axis of the major component was perpendicular to the substrate surface whereas that of the minor one inclined ∼10° away from the surface normal. These results suggest that, if properly optimized, epitaxial Y123 films of which the c-axis is dominantly parallel to the substrate normal would be obtained by using the REAlO 3-buffered vicinal substrates whereas doubly tilted Y123 films would occur if instead the normal α-Al 2O 3( 1¯ 0 1 2) substrates without off-cut were used.

  1. An estimate of the second-order in-plane acceleration sensitivity of a Y-cut quartz thickness-shear resonator.

    PubMed

    He, Huijing; Yang, Jiashi; Kosinski, John A

    2015-08-01

    We perform a theoretical analysis of the secondorder in-plane acceleration sensitivity of a Y-cut quartz thickness- shear mode resonator. The second-order nonlinear theory of elasticity for anisotropic crystals is used to determine the biasing fields in the resonator under in-plane acceleration. The acceleration-induced frequency shift is determined from a perturbation analysis based on the plate equations for small-amplitude vibrations superposed on a finite bias. We show that, whereas the first-order acceleration-induced frequency shift is zero for a structurally symmetric resonator under in-plane acceleration, the second-order frequency shift is nonzero and is quadratic in the acceleration. As the fourth-order nonlinear elastic constants of quartz have never been measured, we can only estimate the magnitude of the second-order frequency shift. For a particular case of interest, we find Δω/ω0 ~ 10(-18), 10(-16), and 10(-14) when the acceleration is 1, 10, and 100 g, respectively. PMID:26276952

  2. Effect of annealing on M-plane GaN thin films grown by PAMBE on tilt-cut LAO substrate

    NASA Astrophysics Data System (ADS)

    Lin, Yu-Chiao; Lo, Ikai; Wang, Ying-Chieh; Tsai, Cheng-Da; Yang, Chen-Chi; You, Shuo-Ting; Chou, Ming-Chi; Department of Materials and Optoelectronic Science Collaboration

    2014-03-01

    The non-polar GaN thin film is a potential candidate for high-efficient photoelectric devices. In this work, we analyzed the characteristics of M-plane GaN thin films which were grown on tilt-cut LiAlO2 (LAO) substrate by plasma-assisted molecular beam epitaxy (PAMBE). A series of samples were grown with different N/Ga flux ratios. The crystal structure and optical property of GaN samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence (PL) measurements. The peak of 32.2o in the XRD measurement showed the [1100] oriented (M-plane) for the GaN samples. To improve the crystal quality, we performed the thermal treatment by rapid thermal annealing (RTA) system on these samples and analyzed the crystal structure, surface morphology and optical property of the samples after thermal treatment. The effect of annealing on the M-plane GaN thin films was under investigation. This project is supported by National Science council of Taiwan(101-2112-M-110-006-MY3).

  3. Applying the self-organization feature map (SOM) algorithm to AE-based tool wear monitoring in micro-cutting

    NASA Astrophysics Data System (ADS)

    Yen, Chia-Liang; Lu, Ming-Chyuan; Chen, Jau-Liang

    2013-01-01

    This study applies a self-organization feature map (SOM) neural network to acoustic emission (AE) signal-based tool wear monitoring for a micro-milling process. An experiment was set up to collect the signal during cutting for the system development and performance analysis. The AE signal generated on the workpiece was first transformed to the frequency domain by Fast Fourier transformation (FFT), followed by feature extraction processing using the SOM algorithm. The performance verification in this study adopts a learning vector quantification (LVQ) network to evaluate the effects of the SOM algorithm on the classification performance for tool wear monitoring. To investigate the improvement achieved by the SOM algorithms, this study also investigates cases applying only the LVQ classifier and based on the class mean scatter feature selection (CMSFS) criterion and LVQ. Results show that accurate classification of the tool wear can be obtained by properly selecting features closely related to the tool wear based on the CMSFS and frequency resolution of spectral features. However, the SOM algorithms provide a more reliable methodology of reducing the effect on the system performance contributed by noise or variations in the cutting system.

  4. Guided filter and adaptive learning rate based non-uniformity correction algorithm for infrared focal plane array

    NASA Astrophysics Data System (ADS)

    Sheng-Hui, Rong; Hui-Xin, Zhou; Han-Lin, Qin; Rui, Lai; Kun, Qian

    2016-05-01

    Imaging non-uniformity of infrared focal plane array (IRFPA) behaves as fixed-pattern noise superimposed on the image, which affects the imaging quality of infrared system seriously. In scene-based non-uniformity correction methods, the drawbacks of ghosting artifacts and image blurring affect the sensitivity of the IRFPA imaging system seriously and decrease the image quality visibly. This paper proposes an improved neural network non-uniformity correction method with adaptive learning rate. On the one hand, using guided filter, the proposed algorithm decreases the effect of ghosting artifacts. On the other hand, due to the inappropriate learning rate is the main reason of image blurring, the proposed algorithm utilizes an adaptive learning rate with a temporal domain factor to eliminate the effect of image blurring. In short, the proposed algorithm combines the merits of the guided filter and the adaptive learning rate. Several real and simulated infrared image sequences are utilized to verify the performance of the proposed algorithm. The experiment results indicate that the proposed algorithm can not only reduce the non-uniformity with less ghosting artifacts but also overcome the problems of image blurring in static areas.

  5. Effects of Varying Epoch Lengths, Wear Time Algorithms, and Activity Cut-Points on Estimates of Child Sedentary Behavior and Physical Activity from Accelerometer Data

    PubMed Central

    Banda, Jorge A.; Haydel, K. Farish; Davila, Tania; Desai, Manisha; Haskell, William L.; Matheson, Donna; Robinson, Thomas N.

    2016-01-01

    Objective To examine the effects of accelerometer epoch lengths, wear time (WT) algorithms, and activity cut-points on estimates of WT, sedentary behavior (SB), and physical activity (PA). Methods 268 7–11 year-olds with BMI ≥ 85th percentile for age and sex wore accelerometers on their right hips for 4–7 days. Data were processed and analyzed at epoch lengths of 1-, 5-, 10-, 15-, 30-, and 60-seconds. For each epoch length, WT minutes/day was determined using three common WT algorithms, and minutes/day and percent time spent in SB, light (LPA), moderate (MPA), and vigorous (VPA) PA were determined using five common activity cut-points. ANOVA tested differences in WT, SB, LPA, MPA, VPA, and MVPA when using the different epoch lengths, WT algorithms, and activity cut-points. Results WT minutes/day varied significantly by epoch length when using the NHANES WT algorithm (p < .0001), but did not vary significantly by epoch length when using the ≥ 20 minute consecutive zero or Choi WT algorithms. Minutes/day and percent time spent in SB, LPA, MPA, VPA, and MVPA varied significantly by epoch length for all sets of activity cut-points tested with all three WT algorithms (all p < .0001). Across all epoch lengths, minutes/day and percent time spent in SB, LPA, MPA, VPA, and MVPA also varied significantly across all sets of activity cut-points with all three WT algorithms (all p < .0001). Conclusions The common practice of converting WT algorithms and activity cut-point definitions to match different epoch lengths may introduce significant errors. Estimates of SB and PA from studies that process and analyze data using different epoch lengths, WT algorithms, and/or activity cut-points are not comparable, potentially leading to very different results, interpretations, and conclusions, misleading research and public policy. PMID:26938240

  6. Refinement-Cut: User-Guided Segmentation Algorithm for Translational Science

    PubMed Central

    Egger, Jan

    2014-01-01

    In this contribution, a semi-automatic segmentation algorithm for (medical) image analysis is presented. More precise, the approach belongs to the category of interactive contouring algorithms, which provide real-time feedback of the segmentation result. However, even with interactive real-time contouring approaches there are always cases where the user cannot find a satisfying segmentation, e.g. due to homogeneous appearances between the object and the background, or noise inside the object. For these difficult cases the algorithm still needs additional user support. However, this additional user support should be intuitive and rapid integrated into the segmentation process, without breaking the interactive real-time segmentation feedback. I propose a solution where the user can support the algorithm by an easy and fast placement of one or more seed points to guide the algorithm to a satisfying segmentation result also in difficult cases. These additional seed(s) restrict(s) the calculation of the segmentation for the algorithm, but at the same time, still enable to continue with the interactive real-time feedback segmentation. For a practical and genuine application in translational science, the approach has been tested on medical data from the clinical routine in 2D and 3D. PMID:24893650

  7. Localization and segmentation of optic disc in retinal images using circular Hough transform and grow-cut algorithm.

    PubMed

    Abdullah, Muhammad; Fraz, Muhammad Moazam; Barman, Sarah A

    2016-01-01

    Automated retinal image analysis has been emerging as an important diagnostic tool for early detection of eye-related diseases such as glaucoma and diabetic retinopathy. In this paper, we have presented a robust methodology for optic disc detection and boundary segmentation, which can be seen as the preliminary step in the development of a computer-assisted diagnostic system for glaucoma in retinal images. The proposed method is based on morphological operations, the circular Hough transform and the grow-cut algorithm. The morphological operators are used to enhance the optic disc and remove the retinal vasculature and other pathologies. The optic disc center is approximated using the circular Hough transform, and the grow-cut algorithm is employed to precisely segment the optic disc boundary. The method is quantitatively evaluated on five publicly available retinal image databases DRIVE, DIARETDB1, CHASE_DB1, DRIONS-DB, Messidor and one local Shifa Hospital Database. The method achieves an optic disc detection success rate of 100% for these databases with the exception of 99.09% and 99.25% for the DRIONS-DB, Messidor, and ONHSD databases, respectively. The optic disc boundary detection achieved an average spatial overlap of 78.6%, 85.12%, 83.23%, 85.1%, 87.93%, 80.1%, and 86.1%, respectively, for these databases. This unique method has shown significant improvement over existing methods in terms of detection and boundary extraction of the optic disc. PMID:27190713

  8. Localization and segmentation of optic disc in retinal images using circular Hough transform and grow-cut algorithm

    PubMed Central

    Abdullah, Muhammad; Barman, Sarah A.

    2016-01-01

    Automated retinal image analysis has been emerging as an important diagnostic tool for early detection of eye-related diseases such as glaucoma and diabetic retinopathy. In this paper, we have presented a robust methodology for optic disc detection and boundary segmentation, which can be seen as the preliminary step in the development of a computer-assisted diagnostic system for glaucoma in retinal images. The proposed method is based on morphological operations, the circular Hough transform and the grow-cut algorithm. The morphological operators are used to enhance the optic disc and remove the retinal vasculature and other pathologies. The optic disc center is approximated using the circular Hough transform, and the grow-cut algorithm is employed to precisely segment the optic disc boundary. The method is quantitatively evaluated on five publicly available retinal image databases DRIVE, DIARETDB1, CHASE_DB1, DRIONS-DB, Messidor and one local Shifa Hospital Database. The method achieves an optic disc detection success rate of 100% for these databases with the exception of 99.09% and 99.25% for the DRIONS-DB, Messidor, and ONHSD databases, respectively. The optic disc boundary detection achieved an average spatial overlap of 78.6%, 85.12%, 83.23%, 85.1%, 87.93%, 80.1%, and 86.1%, respectively, for these databases. This unique method has shown significant improvement over existing methods in terms of detection and boundary extraction of the optic disc. PMID:27190713

  9. A real-time guidance algorithm for aerospace plane optimal ascent to low earth orbit

    NASA Astrophysics Data System (ADS)

    Calise, A. J.; Flandro, G. A.; Corban, J. E.

    Problems of onboard trajectory optimization and synthesis of suitable guidance laws for ascent to low Earth orbit of an air-breathing, single-stage-to-orbit vehicle are addressed. A multimode propulsion system is assumed which incorporates turbojet, ramjet, Scramjet, and rocket engines. An algorithm for generating fuel-optimal climb profiles is presented. This algorithm results from the application of the minimum principle to a low-order dynamic model that includes angle-of-attack effects and the normal component of thrust. Maximum dynamic pressure and maximum aerodynamic heating rate constraints are considered. Switching conditions are derived which, under appropriate assumptions, govern optimal transition from one propulsion mode to another. A nonlinear transformation technique is employed to derived a feedback controller for tracking the computed trajectory. Numerical results illustrate the nature of the resulting fuel-optimal climb paths.

  10. A real-time guidance algorithm for aerospace plane optimal ascent to low earth orbit

    NASA Technical Reports Server (NTRS)

    Calise, A. J.; Flandro, G. A.; Corban, J. E.

    1989-01-01

    Problems of onboard trajectory optimization and synthesis of suitable guidance laws for ascent to low Earth orbit of an air-breathing, single-stage-to-orbit vehicle are addressed. A multimode propulsion system is assumed which incorporates turbojet, ramjet, Scramjet, and rocket engines. An algorithm for generating fuel-optimal climb profiles is presented. This algorithm results from the application of the minimum principle to a low-order dynamic model that includes angle-of-attack effects and the normal component of thrust. Maximum dynamic pressure and maximum aerodynamic heating rate constraints are considered. Switching conditions are derived which, under appropriate assumptions, govern optimal transition from one propulsion mode to another. A nonlinear transformation technique is employed to derived a feedback controller for tracking the computed trajectory. Numerical results illustrate the nature of the resulting fuel-optimal climb paths.

  11. An Exact Algorithm to Compute the Double-Cut-and-Join Distance for Genomes with Duplicate Genes.

    PubMed

    Shao, Mingfu; Lin, Yu; Moret, Bernard M E

    2015-05-01

    Computing the edit distance between two genomes is a basic problem in the study of genome evolution. The double-cut-and-join (DCJ) model has formed the basis for most algorithmic research on rearrangements over the last few years. The edit distance under the DCJ model can be computed in linear time for genomes without duplicate genes, while the problem becomes NP-hard in the presence of duplicate genes. In this article, we propose an integer linear programming (ILP) formulation to compute the DCJ distance between two genomes with duplicate genes. We also provide an efficient preprocessing approach to simplify the ILP formulation while preserving optimality. Comparison on simulated genomes demonstrates that our method outperforms MSOAR in computing the edit distance, especially when the genomes contain long duplicated segments. We also apply our method to assign orthologous gene pairs among human, mouse, and rat genomes, where once again our method outperforms MSOAR. PMID:25517208

  12. An Image-plane Algorithm for JWST's Non-redundant Aperture Mask Data

    NASA Astrophysics Data System (ADS)

    Greenbaum, Alexandra Z.; Pueyo, Laurent; Sivaramakrishnan, Anand; Lacour, Sylvestre

    2015-01-01

    The high angular resolution technique of non-redundant masking (NRM) or aperture masking interferometry (AMI) has yielded images of faint protoplanetary companions of nearby stars from the ground. AMI on James Webb Space Telescope (JWST)'s Near Infrared Imager and Slitless Spectrograph (NIRISS) has a lower thermal background than ground-based facilities and does not suffer from atmospheric instability. NIRISS AMI images are likely to have 90%-95% Strehl ratio between 2.77 and 4.8 μm. In this paper we quantify factors that limit the raw point source contrast of JWST NRM. We develop an analytic model of the NRM point spread function which includes different optical path delays (pistons) between mask holes and fit the model parameters with image plane data. It enables a straightforward way to exclude bad pixels, is suited to limited fields of view, and can incorporate effects such as intra-pixel sensitivity variations. We simulate various sources of noise to estimate their effect on the standard deviation of closure phase, σCP (a proxy for binary point source contrast). If σCP < 10-4 radians—a contrast ratio of 10 mag—young accreting gas giant planets (e.g., in the nearby Taurus star-forming region) could be imaged with JWST NIRISS. We show the feasibility of using NIRISS' NRM with the sub-Nyquist sampled F277W, which would enable some exoplanet chemistry characterization. In the presence of small piston errors, the dominant sources of closure phase error (depending on pixel sampling, and filter bandwidth) are flat field errors and unmodeled variations in intra-pixel sensitivity. The in-flight stability of NIRISS will determine how well these errors can be calibrated by observing a point source. Our results help develop efficient observing strategies for space-based NRM.

  13. AN IMAGE-PLANE ALGORITHM FOR JWST'S NON-REDUNDANT APERTURE MASK DATA

    SciTech Connect

    Greenbaum, Alexandra Z.; Pueyo, Laurent; Sivaramakrishnan, Anand; Lacour, Sylvestre

    2015-01-10

    The high angular resolution technique of non-redundant masking (NRM) or aperture masking interferometry (AMI) has yielded images of faint protoplanetary companions of nearby stars from the ground. AMI on James Webb Space Telescope (JWST)'s Near Infrared Imager and Slitless Spectrograph (NIRISS) has a lower thermal background than ground-based facilities and does not suffer from atmospheric instability. NIRISS AMI images are likely to have 90%-95% Strehl ratio between 2.77 and 4.8 μm. In this paper we quantify factors that limit the raw point source contrast of JWST NRM. We develop an analytic model of the NRM point spread function which includes different optical path delays (pistons) between mask holes and fit the model parameters with image plane data. It enables a straightforward way to exclude bad pixels, is suited to limited fields of view, and can incorporate effects such as intra-pixel sensitivity variations. We simulate various sources of noise to estimate their effect on the standard deviation of closure phase, σ{sub CP} (a proxy for binary point source contrast). If σ{sub CP} < 10{sup –4} radians—a contrast ratio of 10 mag—young accreting gas giant planets (e.g., in the nearby Taurus star-forming region) could be imaged with JWST NIRISS. We show the feasibility of using NIRISS' NRM with the sub-Nyquist sampled F277W, which would enable some exoplanet chemistry characterization. In the presence of small piston errors, the dominant sources of closure phase error (depending on pixel sampling, and filter bandwidth) are flat field errors and unmodeled variations in intra-pixel sensitivity. The in-flight stability of NIRISS will determine how well these errors can be calibrated by observing a point source. Our results help develop efficient observing strategies for space-based NRM.

  14. An algorithm to extract effective magnetic parameters of thin film with in-plane uniaxial magnetic anisotropy

    NASA Astrophysics Data System (ADS)

    Neo, C. P.; Ding, J.

    2010-05-01

    The calculation of high frequency complex permeability of thin ferromagnetic film requires the measured values of its saturation magnetization, anisotropic magnetic field intensity, resistivity, and thickness. It is often observed that the calculated permeability using the Landau-Lifshitz-Gilbert (LLG) theory does not agree well with the measured permeability of thin film with in-plane uniaxial magnetic anisotropy, owing to the measured anisotropic magnetic field intensity, saturation magnetization, etc., are not effective values at high frequency. In this work, the Landau-Lifshitz ferromagnetic resonance model is modified to take the skin depth effect into consideration. In the comparison study, its calculated magnetic permeability curves (real and imaginary) agrees very well with those calculated from the LLG model. In addition, an algorithm process to extract effective magnetic parameters (saturation magnetization Ms, magnetic anisotropy field Ha, and damping factor α) has been developed. The algorithm process has been tested for the reported magnetic permeability curves of two magnetic films (Si/NiFe/FeCoB and CoZrRe). The extracted parameters are well agreed with those reported. It is also reported that the consideration of skin depth effect is necessary for samples with lower electrical resistivity.

  15. US-Cut: interactive algorithm for rapid detection and segmentation of liver tumors in ultrasound acquisitions

    NASA Astrophysics Data System (ADS)

    Egger, Jan; Voglreiter, Philip; Dokter, Mark; Hofmann, Michael; Chen, Xiaojun; Zoller, Wolfram G.; Schmalstieg, Dieter; Hann, Alexander

    2016-04-01

    Ultrasound (US) is the most commonly used liver imaging modality worldwide. It plays an important role in follow-up of cancer patients with liver metastases. We present an interactive segmentation approach for liver tumors in US acquisitions. Due to the low image quality and the low contrast between the tumors and the surrounding tissue in US images, the segmentation is very challenging. Thus, the clinical practice still relies on manual measurement and outlining of the tumors in the US images. We target this problem by applying an interactive segmentation algorithm to the US data, allowing the user to get real-time feedback of the segmentation results. The algorithm has been developed and tested hand-in-hand by physicians and computer scientists to make sure a future practical usage in a clinical setting is feasible. To cover typical acquisitions from the clinical routine, the approach has been evaluated with dozens of datasets where the tumors are hyperechoic (brighter), hypoechoic (darker) or isoechoic (similar) in comparison to the surrounding liver tissue. Due to the interactive real-time behavior of the approach, it was possible even in difficult cases to find satisfying segmentations of the tumors within seconds and without parameter settings, and the average tumor deviation was only 1.4mm compared with manual measurements. However, the long term goal is to ease the volumetric acquisition of liver tumors in order to evaluate for treatment response. Additional aim is the registration of intraoperative US images via the interactive segmentations to the patient's pre-interventional CT acquisitions.

  16. Identification of Shearer Cutting Patterns Using Vibration Signals Based on a Least Squares Support Vector Machine with an Improved Fruit Fly Optimization Algorithm.

    PubMed

    Si, Lei; Wang, Zhongbin; Liu, Xinhua; Tan, Chao; Liu, Ze; Xu, Jing

    2016-01-01

    Shearers play an important role in fully mechanized coal mining face and accurately identifying their cutting pattern is very helpful for improving the automation level of shearers and ensuring the safety of coal mining. The least squares support vector machine (LSSVM) has been proven to offer strong potential in prediction and classification issues, particularly by employing an appropriate meta-heuristic algorithm to determine the values of its two parameters. However, these meta-heuristic algorithms have the drawbacks of being hard to understand and reaching the global optimal solution slowly. In this paper, an improved fly optimization algorithm (IFOA) to optimize the parameters of LSSVM was presented and the LSSVM coupled with IFOA (IFOA-LSSVM) was used to identify the shearer cutting pattern. The vibration acceleration signals of five cutting patterns were collected and the special state features were extracted based on the ensemble empirical mode decomposition (EEMD) and the kernel function. Some examples on the IFOA-LSSVM model were further presented and the results were compared with LSSVM, PSO-LSSVM, GA-LSSVM and FOA-LSSVM models in detail. The comparison results indicate that the proposed approach was feasible, efficient and outperformed the others. Finally, an industrial application example at the coal mining face was demonstrated to specify the effect of the proposed system. PMID:26771615

  17. Identification of Shearer Cutting Patterns Using Vibration Signals Based on a Least Squares Support Vector Machine with an Improved Fruit Fly Optimization Algorithm

    PubMed Central

    Si, Lei; Wang, Zhongbin; Liu, Xinhua; Tan, Chao; Liu, Ze; Xu, Jing

    2016-01-01

    Shearers play an important role in fully mechanized coal mining face and accurately identifying their cutting pattern is very helpful for improving the automation level of shearers and ensuring the safety of coal mining. The least squares support vector machine (LSSVM) has been proven to offer strong potential in prediction and classification issues, particularly by employing an appropriate meta-heuristic algorithm to determine the values of its two parameters. However, these meta-heuristic algorithms have the drawbacks of being hard to understand and reaching the global optimal solution slowly. In this paper, an improved fly optimization algorithm (IFOA) to optimize the parameters of LSSVM was presented and the LSSVM coupled with IFOA (IFOA-LSSVM) was used to identify the shearer cutting pattern. The vibration acceleration signals of five cutting patterns were collected and the special state features were extracted based on the ensemble empirical mode decomposition (EEMD) and the kernel function. Some examples on the IFOA-LSSVM model were further presented and the results were compared with LSSVM, PSO-LSSVM, GA-LSSVM and FOA-LSSVM models in detail. The comparison results indicate that the proposed approach was feasible, efficient and outperformed the others. Finally, an industrial application example at the coal mining face was demonstrated to specify the effect of the proposed system. PMID:26771615

  18. Apparatus for cutting elastomeric materials

    NASA Technical Reports Server (NTRS)

    Corbett, A. B.

    1974-01-01

    Sharp thin cutting edge is held in head of milling machine designed for metal working. Controls of machine are used to position cutting edge in same plane as vibrating specimen. Controls then are operated, making blade come into contact with specimen, to cut it into shapes and sizes desired. Cut surfaces appear mirror-smooth; vibrating mechanism causes no visible striations.

  19. Characterization of ZnO thin film grown on c-plane substrates by MO-CVD: Effect of substrate annealing temperature, vicinal-cut angle and miscut direction

    NASA Astrophysics Data System (ADS)

    Boukadhaba, M. A.; Fouzri, A.; Sallet, V.; Hassani, S. S.; Amiri, G.; Lusson, A.; Oumezzine, M.

    2015-09-01

    The annealing effects of c-plane sapphire (α-Al2O3) substrate with a nominally vicinal-cut angle α (α < 0.1°, α = 0.25° toward the m-plane (1 0 1 bar 0) and α = 0.25° toward the a-plane (1 1 2 bar 0)) on the quality of epitaxial ZnO films grown by metal organic chemical vapor deposition (MO-CVD) were studied. The atomic steps formed on sapphire substrate surface by annealing at high temperature were analyzed by atomic force microscopy (AFM). The annealing and the miscut direction of sapphire substrate on the microstructural and optical properties for ZnO films were examined by high resolution X-ray diffraction (HR-XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and photoluminescence spectroscopy (PL). Experimental results indicate that the film quality is strongly affected by annealing treatment and miscut direction of the sapphire substrate. X-ray diffraction study revealed that all films exhibit a wurtzite phase and have a c-axis orientation. ZnO films deposited on sapphire substrate (α < 0.1° and α = 0.25° toward the m-plane (1 0 1 bar 0), annealed substrate at 1100 °C), exhibit a low quantity of defects and a quite good vertical and lateral alignment compared to other disorientation plane (α = 0.25° toward the a-plane (1 1 2 bar 0), annealed substrate at 1100 °C). The Lattice parameters a and c slightly decreases for ZnO layer deposited on annealed sapphire substrate with increase the annealing substrate temperature for all samples. AFM image show significant differences between morphologies of samples depending on annealing treatment and miscut direction of substrates but no significant differences on surface roughness have been found. Sapphire annealing at 1100 °C with a nominally vicinal-cut angle α = 0.25° toward the m-plane (1 0 1 bar 0), provides the best optical quality of ZnO film.

  20. Numerical phase retrieval from beam intensity measurements in three planes

    NASA Astrophysics Data System (ADS)

    Bruel, Laurent

    2003-05-01

    A system and method have been developed at CEA to retrieve phase information from multiple intensity measurements along a laser beam. The device has been patented. Commonly used devices for beam measurement provide phase and intensity information separately or with a rather poor resolution whereas the MIROMA method provides both at the same time, allowing direct use of the results in numerical models. Usual phase retrieval algorithms use two intensity measurements, typically the image plane and the focal plane (Gerschberg-Saxton algorithm) related by a Fourier transform, or the image plane and a lightly defocus plane (D.L. Misell). The principal drawback of such iterative algorithms is their inability to provide unambiguous convergence in all situations. The algorithms can stagnate on bad solutions and the error between measured and calculated intensities remains unacceptable. If three planes rather than two are used, the data redundancy created confers to the method good convergence capability and noise immunity. It provides an excellent agreement between intensity determined from the retrieved phase data set in the image plane and intensity measurements in any diffraction plane. The method employed for MIROMA is inspired from GS algorithm, replacing Fourier transforms by a beam-propagating kernel with gradient search accelerating techniques and special care for phase branch cuts. A fast one dimensional algorithm provides an initial guess for the iterative algorithm. Applications of the algorithm on synthetic data find out the best reconstruction planes that have to be chosen. Robustness and sensibility are evaluated. Results on collimated and distorted laser beams are presented.

  1. Operationalizing hippocampal volume as an enrichment biomarker for amnestic MCI trials: effect of algorithm, test-retest variability and cut-point on trial cost, duration and sample size

    PubMed Central

    Yu, P.; Sun, J.; Wolz, R.; Stephenson, D.; Brewer, J.; Fox, N.C.; Cole, P.E.; Jack, C.R.; Hill, D.L.G.; Schwarz, A.J.

    2014-01-01

    Objective To evaluate the effect of computational algorithm, measurement variability and cut-point on hippocampal volume (HCV)-based patient selection for clinical trials in mild cognitive impairment (MCI). Methods We used normal control and amnestic MCI subjects from ADNI-1 as normative reference and screening cohorts. We evaluated the enrichment performance of four widely-used hippocampal segmentation algorithms (FreeSurfer, HMAPS, LEAP and NeuroQuant) in terms of two-year changes in MMSE, ADAS-Cog and CDR-SB. We modeled the effect of algorithm, test-retest variability and cut-point on sample size, screen fail rates and trial cost and duration. Results HCV-based patient selection yielded not only reduced sample sizes (by ~40–60%) but also lower trial costs (by ~30–40%) across a wide range of cut-points. Overall, the dependence on the cut-point value was similar for the three clinical instruments considered. Conclusion These results provide a guide to the choice of HCV cut-point for aMCI clinical trials, allowing an informed trade-off between statistical and practical considerations. PMID:24211008

  2. Cutting assembly

    DOEpatents

    Racki, Daniel J.; Swenson, Clark E.; Bencloski, William A.; Wineman, Arthur L.

    1984-01-01

    A cutting apparatus includes a support table mounted for movement toward and away from a workpiece and carrying a mirror which directs a cutting laser beam onto the workpiece. A carrier is rotatably and pivotally mounted on the support table between the mirror and workpiece and supports a conduit discharging gas toward the point of impingement of the laser beam on the workpiece. Means are provided for rotating the carrier relative to the support table to place the gas discharging conduit in the proper positions for cuts made in different directions on the workpiece.

  3. Operationalizing hippocampal volume as an enrichment biomarker for amnestic mild cognitive impairment trials: effect of algorithm, test-retest variability, and cut point on trial cost, duration, and sample size.

    PubMed

    Yu, Peng; Sun, Jia; Wolz, Robin; Stephenson, Diane; Brewer, James; Fox, Nick C; Cole, Patricia E; Jack, Clifford R; Hill, Derek L G; Schwarz, Adam J

    2014-04-01

    The objective of this study was to evaluate the effect of computational algorithm, measurement variability, and cut point on hippocampal volume (HCV)-based patient selection for clinical trials in mild cognitive impairment (MCI). We used normal control and amnestic MCI subjects from the Alzheimer's Disease Neuroimaging Initiative 1 (ADNI-1) as normative reference and screening cohorts. We evaluated the enrichment performance of 4 widely used hippocampal segmentation algorithms (FreeSurfer, Hippocampus Multi-Atlas Propagation and Segmentation (HMAPS), Learning Embeddings Atlas Propagation (LEAP), and NeuroQuant) in terms of 2-year changes in Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), and Clinical Dementia Rating Sum of Boxes (CDR-SB). We modeled the implications for sample size, screen fail rates, and trial cost and duration. HCV based patient selection yielded reduced sample sizes (by ∼40%-60%) and lower trial costs (by ∼30%-40%) across a wide range of cut points. These results provide a guide to the choice of HCV cut point for amnestic MCI clinical trials, allowing an informed tradeoff between statistical and practical considerations. PMID:24211008

  4. Cutting Candles

    ERIC Educational Resources Information Center

    Ranucci, Ernest R.

    1973-01-01

    Different regular-polygon-shaped candles wound with a sheet of paper are cut through obliquely. When the papers are unwound, unique patterns are revealed. Investigation of these patterns leads to the discovery of geometric concepts. (JP)

  5. X-Z-Theta cutting method

    DOEpatents

    Bieg, L.F.

    1993-01-12

    A method for machining a workpiece. The method includes the use of a rotary cutting tool mounted on the end of a movable arm. The arm is adapted to move in a plane perpendicular to the axis of rotation of the cutting tool. The cutting tool has cutting teeth to cut chips of material off of the workpiece in a predetermined size and shape to facilitate better removal of the chips from the workpiece. The teeth can be of different type and length to permit the tool to both rough cut and finish cut the workpiece during machining. The total depth of cut is divided by the number of tool teeth, so that the longest tool always performs the finishing cut.

  6. 6. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM MIDSLOPE VICINITY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM MID-SLOPE VICINITY, CUT CONFIGURATION - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  7. Cutting holes in fabric-faced panels

    NASA Technical Reports Server (NTRS)

    Peterson, S. A.

    1981-01-01

    Tool has 2 carbide inserts that bore clean holes through fibrous material with knifelike slicing action. Cutting edge of insert is curved, with plane inner surface at 30 degree angle to tool axis. Drill press or hand-held drill can be used to hold cutting tool.

  8. Cut Costs without Cutting Quality.

    ERIC Educational Resources Information Center

    Pereus, Steven C.

    2000-01-01

    Districts can save 5 to 10 percent of budgets without damaging student services by adhering to certain principles: utilize public funds efficiently; set service-improvement and cost-cutting goals; involve and reward employees for improvement efforts; and use management systems, business techniques, and information technology. (MLH)

  9. Document segmentation via oblique cuts

    NASA Astrophysics Data System (ADS)

    Svendsen, Jeremy; Branzan-Albu, Alexandra

    2013-01-01

    This paper presents a novel solution for the layout segmentation of graphical elements in Business Intelligence documents. We propose a generalization of the recursive X-Y cut algorithm, which allows for cutting along arbitrary oblique directions. An intermediate processing step consisting of line and solid region removal is also necessary due to presence of decorative elements. The output of the proposed segmentation is a hierarchical structure which allows for the identification of primitives in pie and bar charts. The algorithm was tested on a database composed of charts from business documents. Results are very promising.

  10. A sphere-cut-splice crossover for the evolution of cluster structures

    NASA Astrophysics Data System (ADS)

    Chen, Zhanghui; Jiang, Xiangwei; Li, Jingbo; Li, Shushen

    2013-06-01

    A new crossover operator is proposed to evolve the structures of the atomic clusters. It uses a sphere rather than a plane to cut and splice the parent structures. The child cluster is constructed by the atoms of one parent which lie inside the sphere, and the atoms of the other parent which lie outside the sphere. It can reliably produce reasonable offspring and preserve the good schemata in parent structures, avoiding the drawbacks of the classical plane-cut-splice crossover in the global searching ability and the local optimization speed. Results of Lennard-Jones clusters (30 ⩽ N ⩽ 500) show that at the same settings the genetic algorithm with the sphere-cut-splice crossover exhibits better performance than the one with the plane-cut-splice crossover. The average number of local minimizations needed to find the global minima and the average number of energy evaluation of each local minimization in the sphere scheme is 0.8075 and 0.8386 of that in the plane scheme, respectively. The mean speed-up ratio for the entire testing clusters reaches 1.8207. Moreover, the sphere scheme is particularly suitable for large clusters and the mean speed-up ratio reaches 2.3520 for the clusters with 110 ⩽ N ⩽ 500. The comparison with other successful methods in previous studies also demonstrates its good performance. Finally, a further analysis is presented on the statistical features of the cutting sphere and a modified strategy that reduces the probability of using tiny and large spheres exhibits better global search.

  11. Towards a MIP-Cut Metascheme

    NASA Astrophysics Data System (ADS)

    Fischetti, Matteo

    Cutting planes (cuts) are very popular in the OR community, where they are used to strengthen the Linear Programming (LP) relaxation of Mixed-Integer Programs (MIPs) in the hope of improving the performance of an exact LP-based solver. In particular, an intense research effort has been devoted to the study of families of general cuts, whose validity does not require the presence of a specific MIP structure - as opposed to problem-specific cuts such as, e.g., subtour elimination or comb inequalities for the traveling salesman problem.

  12. Micromachined cutting blade formed from {211}-oriented silicon

    DOEpatents

    Fleming, James G.; Fleming, legal representative, Carol; Sniegowski, Jeffry J.; Montague, Stephen

    2011-08-09

    A cutting blade is disclosed fabricated of micromachined silicon. The cutting blade utilizes a monocrystalline silicon substrate having a {211} crystalline orientation to form one or more cutting edges that are defined by the intersection of {211} crystalline planes of silicon with {111} crystalline planes of silicon. This results in a cutting blade which has a shallow cutting-edge angle .theta. of 19.5.degree.. The micromachined cutting blade can be formed using an anisotropic wet etching process which substantially terminates etching upon reaching the {111} crystalline planes of silicon. This allows multiple blades to be batch fabricated on a common substrate and separated for packaging and use. The micromachined cutting blade, which can be mounted to a handle in tension and optionally coated for increased wear resistance and biocompatibility, has multiple applications including eye surgery (LASIK procedure).

  13. Micromachined cutting blade formed from {211}-oriented silicon

    DOEpatents

    Fleming, James G.; Sniegowski, Jeffry J.; Montague, Stephen

    2003-09-09

    A cutting blade is disclosed fabricated of micromachined silicon. The cutting blade utilizes a monocrystalline silicon substrate having a {211} crystalline orientation to form one or more cutting edges that are defined by the intersection of {211} crystalline planes of silicon with {111} crystalline planes of silicon. This results in a cutting blade which has a shallow cutting-edge angle .theta. of 19.5.degree.. The micromachined cutting blade can be formed using an anisotropic wet etching process which substantially terminates etching upon reaching the {111} crystalline planes of silicon. This allows multiple blades to be batch fabricated on a common substrate and separated for packaging and use. The micromachined cutting blade, which can be mounted to a handle in tension and optionally coated for increased wear resistance and biocompatibility, has multiple applications including eye surgery (LASIK procedure).

  14. FFT applications to plane-polar near-field antenna measurements

    NASA Technical Reports Server (NTRS)

    Gatti, Mark S.; Rahmat-Samii, Yahya

    1988-01-01

    The four-point bivariate Lagrange interpolation algorithm was applied to near-field antenna data measured in a plane-polar facility. The results were sufficiently accurate to permit the use of the FFT (fast Fourier transform) algorithm to calculate the far-field patterns of the antenna. Good agreement was obtained between the far-field patterns as calculated by the Jacobi-Bessel and the FFT algorithms. The significant advantage in using the FFT is in the calculation of the principal plane cuts, which may be made very quickly. Also, the application of the FFT algorithm directly to the near-field data was used to perform surface holographic diagnosis of a reflector antenna. The effects due to the focusing of the emergent beam from the reflector, as well as the effects of the information in the wide-angle regions, are shown. The use of the plane-polar near-field antenna test range has therfore been expanded to include these useful FFT applications.

  15. The mechanics of slitting and cutting webs

    NASA Astrophysics Data System (ADS)

    Meehan, Richard Raymond

    The quality of edges formed during cutting and slitting of thin polymer webs is important for many industrial applications. In order to control the edge quality of the separated material, it is necessary to understand cutting. A model is proposed and the mechanics of cutting are described. An apparatus was constructed to instrument, monitor and control the web slitting process. The slitting speed, tension in the web, blade sharpness and angle of cut were varied during tests. This allowed a quantitative understanding of the cutting mechanisms to be established. The results of the experiments showed the in-plane cutting forces were minimally affected by changes in rate or speed and independent of web tension for sharp blades. The angle of cut had a pronounced effect on the in-plane cutting forces and the stability of the cut. Further experimentation was designed to relate force to plastic deformation caused by a wedge indenting the edge surface of a polymer sample. These experiments clearly revealed the shape of the plastic deformation zone ahead of and around the wedges. Data from the experiments showed increasing cutting force with wedge displacement until the sample fractured. Plastic deformation of the samples was then examined in detail. The results showed out-of-plane plastic volume was equal to the volume displaced by the wedge. Samples also exhibited constant hardness during initial phases of wedge indenting. A finite element model concurred with the empirical plastic zone data. An innovative method was developed to take a dynamic "snapshot" of web displacement around the blade. The results clearly showed the web buckling ahead of the blade producing major instability during the cutting and slitting of thin webs. A finite element model supported the characteristics of the buckling phenomena observed in thin webs. An understanding of the interaction of cutting parameters and the buckling instability will allow quality web edges with minimal deformation and

  16. Algorithm for Constructing Contour Plots

    NASA Technical Reports Server (NTRS)

    Johnson, W.; Silva, F.

    1984-01-01

    General computer algorithm developed for construction of contour plots. algorithm accepts as input data values at set of points irregularly distributed over plane. Algorithm based on interpolation scheme: points in plane connected by straight-line segments to form set of triangles. Program written in FORTRAN IV.

  17. Portable cutting apparatus

    DOEpatents

    Gilmore, R.F.

    1984-07-17

    A remotely operable, portable cutting apparatus detachably secured to the workpiece by laterally spaced clamp assemblies engagable with the workpiece on opposite sides of the intended line of cut. A reciprocal cutter head is mounted between the clamp assemblies and is provided with a traveling abrasive cutting wire adapted to sever the workpiece normal to the longitudinal axis thereof. Dust and debris are withdrawn from the cutting area by a vacuum force through a nozzle mounted on the cutting head.

  18. Portable cutting apparatus

    DOEpatents

    Gilmore, Richard F.

    1986-04-01

    A remotely operable, portable cutting apparatus detachably secured to the workpiece by laterally spaced clamp assemblies engageable with the workpiece on opposite sides of the intended line of cut. A reciprocal cutter head is mounted between the clamp assemblies and is provided with a traveling abrasive cutting wire adapted to sever the workpiece normal to the longitudinal axis thereof. Dust and debris are withdrawn from the cutting area by a vacuum force through a nozzle mounted on the cutting head.

  19. Portable cutting apparatus

    DOEpatents

    Gilmore, Richard F.

    1986-01-01

    A remotely operable, portable cutting apparatus detachably secured to the workpiece by laterally spaced clamp assemblies engageable with the workpiece on opposite sides of the intended line of cut. A reciprocal cutter head is mounted between the clamp assemblies and is provided with a traveling abrasive cutting wire adapted to sever the workpiece normal to the longitudinal axis thereof. Dust and debris are withdrawn from the cutting area by a vacuum force through a nozzle mounted on the cutting head.

  20. 7. VIEW WEST, PERSPECTIVE VIEW OF TOP OF INCLINED PLANE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW WEST, PERSPECTIVE VIEW OF TOP OF INCLINED PLANE AND EAST FACE OF CUT STONE TOWER - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  1. Phase unwrapping via graph cuts.

    PubMed

    Bioucas-Dias, José M; Valadão, Gonçalo

    2007-03-01

    Phase unwrapping is the inference of absolute phase from modulo-2pi phase. This paper introduces a new energy minimization framework for phase unwrapping. The considered objective functions are first-order Markov random fields. We provide an exact energy minimization algorithm, whenever the corresponding clique potentials are convex, namely for the phase unwrapping classical Lp norm, with p > or = 1. Its complexity is KT (n, 3n), where K is the length of the absolute phase domain measured in 2pi units and T (n, m) is the complexity of a max-flow computation in a graph with n nodes and m edges. For nonconvex clique potentials, often used owing to their discontinuity preserving ability, we face an NP-hard problem for which we devise an approximate solution. Both algorithms solve integer optimization problems by computing a sequence of binary optimizations, each one solved by graph cut techniques. Accordingly, we name the two algorithms PUMA, for phase unwrappping max-flow/min-cut. A set of experimental results illustrates the effectiveness of the proposed approach and its competitiveness in comparison with state-of-the-art phase unwrapping algorithms. PMID:17357730

  2. Cutting state identification

    SciTech Connect

    Berger, B.S.; Minis, I.; Rokni, M.

    1997-12-31

    Cutting states associated with the orthogonal cutting of stiff cylinders are identified through an analysis of the singular values of a Toeplitz matrix of third order cumulants of acceleration measurements. The ratio of the two pairs of largest singular values is shown to differentiate between light cutting, medium cutting, pre-chatter and chatter states. Sequences of cutting experiments were performed in which either depth of cut or turning frequency was varied. Two sequences of experiments with variable turning frequency and five with variable depth of cut, 42 cutting experiments in all, provided a database for the calculation of third order cumulants. Ratios of singular values of cumulant matrices find application in the analysis of control of orthogonal cutting.

  3. On triangulations of the plane by pencils of conics. II

    SciTech Connect

    Lazareva, V B; Shelekhov, A M

    2013-06-30

    The present work continues our previous paper in which all possible triangulations of the plane using three pencils of circles were listed. In the present article we find all projectively distinct triangulations of the plane by pencils of conics that are obtained by projecting regular three-webs, cut out on a nondegenerate cubic surface by three pencils of planes, whose axes lie on this surface. Bibliography: 6 titles.

  4. Orbital Space Plane (OSP) Program

    NASA Technical Reports Server (NTRS)

    McKenzie, Patrick M.

    2003-01-01

    Lockheed Martin has been an active participant in NASA's Space Launch Initiative (SLI) programs over the past several years. SLI, part of NASA's Integrated Space Transportation Plan (ISTP), was restructured in November of 2002 to focus the overall theme of safer, more afford-able space transportation along two paths - the Orbital Space Plane Program and the Next Generation Launch Technology programs. The Orbital Space Plane Program has the goal of providing rescue capability from the International Space Station by 2008 and transfer capability for crew (and limited cargo) by 2012. The Next Generation Launch Technology program is combining research and development efforts from the 2nd Generation Reusable Launch Vehicle (2GRLV) program with cutting-edge, advanced space transportation programs (previously designated 3rd Generation) into one program aimed at enabling safe, reliable, cost-effective reusable launch systems by the middle of the next decade. Lockheed Martin is one of three prime contractors working to bring Orbital Space Plane system concepts to a system definition level of maturity by December of 2003. This paper and presentation will update the international community on the progress of the' OSP program, from an industry perspective, and provide insights into Lockheed Martin's role in enabling the vision of a safer, more affordable means of taking people to and from space.

  5. Reconnaissance with slant plane circular SAR imaging.

    PubMed

    Soumekh, M

    1996-01-01

    This paper presents a method for imaging from the slant plane data collected by a synthetic aperture radar (SAR) over the full rotation or a partial segment of a circular flight path. A Fourier analysis for the Green's function of the imaging system is provided. This analysis is the basis of an inversion for slant plane circular SAR data. The reconstruction algorithm and resolution for this SAR system are outlined. It is shown that the slant plane circular SAR, unlike the slant plane linear SAR, has the capability to extract three-dimensional imaging information of a target scene. The merits of the algorithm are demonstrated via a simulated target whose ultra wideband foliage penetrating (FOPEN) or ground penetrating (GPEN) ultrahigh frequency (UHF) radar signature varies with the radar's aspect angle. PMID:18285213

  6. Cuts and puncture wounds

    MedlinePlus

    ... cuts and puncture wounds can be treated at home. Take the following steps. FOR MINOR CUTS Wash your hands with soap or antibacterial ... and scissors safely. Make sure you and your child are up to date on vaccinations . A tetanus vaccine is generally recommended every 10 ... Snake bite Minor cut - first aid Sewing a wound closed - series ...

  7. Device for cutting protrusions

    DOEpatents

    Bzorgi, Fariborz M.

    2011-07-05

    An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade. The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.

  8. Laser cutting plastic materials

    SciTech Connect

    Van Cleave, R.A.

    1980-08-01

    A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

  9. Characterization of metal cutting dynamics. Final report

    SciTech Connect

    Berger, B.S.; Minis, I.

    1997-11-01

    A Hardinge CNC lathe has been fitted with sensors and a data acquisition system for the measurement, processing and storage of accelerations and forces associated with orthogonal cutting. This system has been completely validated. Orthogonal cutting experiments were designed in order to study the effects of critical cutting parameters on machining dynamics. Three major experimental sets were conducted. In the first set the depth of cut was increased in a stepwise fashion, while the workpiece surface speed, the spindle speed, and the tool feedrate were maintained invariant. In the second and third sets, the spindle speed and feedrate were varied, respectively, while maintaining all the other parameters invariant. In total over two hundred orthogonal cutting experiments were performed. In each experiment, the two non-zero components of the tool acceleration and the two non-zero components of the cutting force were measured. Despite high noise levels, mutual information calculations with smoothing kernels and false nearest neighbor algorithms proved to be sufficiently robust to provide upper bounds on attractor dimension for all fifty data sets studied. These results prove that the infinite dimensional cutting process has an associated attractor of dimension {le} 4. This result is important as a guide to model construction. An analysis of the power spectral sideband structure proved that sideband spacing is identical to the turning frequency. This result was further substantiated through envelope detection techniques. A linear delay model was shown to emulate the experimental power spectrum and possess predictive capacity.

  10. Ultrasonic Cutting of Foods

    NASA Astrophysics Data System (ADS)

    Schneider, Yvonne; Zahn, Susann; Rohm, Harald

    In the field of food engineering, cutting is usually classified as a mechanical unit operation dealing with size reduction by applying external forces on a bulk product. Ultrasonic cutting is realized by superpositioning the macroscopic feed motion of the cutting device or of the product with a microscopic vibration of the cutting tool. The excited tool interacts with the product and generates a number of effects. Primary energy concentration in the separation zone and the modification of contact friction along the tool flanks arise from the cyclic loading and are responsible for benefits such as reduced cutting force, smooth cut surface, and reduced product deformation. Secondary effects such as absorption and cavitation originate from the propagation of the sound field in the product and are closely related to chemical and physical properties of the material to be cut. This chapter analyzes interactions between food products and ultrasonic cutting tools and relates these interactions with physical and chemical product properties as well as with processing parameters like cutting velocity, ultrasonic amplitude and frequency, and tool design.

  11. Cutting work in thick section cryomicrotomy.

    PubMed

    Saubermann, A J; Riley, W D; Beeuwkes, R

    1977-09-01

    The forces during cryosectioning were measured using miniature strain gauges attached to a load cell fitted to the drive arm of the Porter-Blum MT-2 cryomicrotome. Work was calculated and the data normalized to a standard (1 mm X 1 mm X 0.5 micrometer) section. Thermal energy generated was also calculated. Five parameters were studied: cutting angle, thickness, temperature, hardness, and block shape. Force patterns could be divided into three major groups thought to represent cutting (Type I), large fracture planes greater than 10 micrometer in length (Type II), and small fracture planes less than 10 micrometer in length (Type III). Type I and Type II produced satisfactory sections. Work in cutting ranged from an average of 78.4 muJ to 568.8 muJ. Cutting angle and temperature had the greatest effect on sectioning. Heat generated would be sufficient to cause through-section melting for 0.5 micrometer thick sections assuming the worst possible case, namely that all heat went into the section without loss. Presence of a Type II pattern (large fracture pattern) is thought to be presumptive evidence against thawing. PMID:606833

  12. Experiments with Planing Surfaces

    NASA Technical Reports Server (NTRS)

    Sottorf, W

    1934-01-01

    A previous report discusses the experimental program of a systematic exploration of all questions connected with the planing problem as well as the first fundamental results of the investigation of a flat planing surface. The present report is limited to the conversion of the model test data to full scale.

  13. Starting Trees from Cuttings.

    ERIC Educational Resources Information Center

    Kramer, David C.

    1983-01-01

    Describes a procedure for starting tree cuttings from woody plants, explaining "lag time," recommending materials, and giving step-by-step instructions for rooting and planting. Points out species which are likely candidates for cuttings and provides tips for teachers for developing a unit. (JM)

  14. Cutting Class Harms Grades

    ERIC Educational Resources Information Center

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  15. When Students Cut Themselves

    ERIC Educational Resources Information Center

    Malikow, Max

    2006-01-01

    Masochism, the irrational self-infliction of pain, is more easily defined than understood. Once, a teacher used the word "cutting" only reference to a student skipping class. But, in recent years, it has taken on additional meaning. Cutting, or self-injury, is a deliberate self-harming behavior but without conscious suicidal ideation. To define…

  16. Fundamentals of cutting.

    PubMed

    Williams, J G; Patel, Y

    2016-06-01

    The process of cutting is analysed in fracture mechanics terms with a view to quantifying the various parameters involved. The model used is that of orthogonal cutting with a wedge removing a layer of material or chip. The behaviour of the chip is governed by its thickness and for large radii of curvature the chip is elastic and smooth cutting occurs. For smaller thicknesses, there is a transition, first to plastic bending and then to plastic shear for small thicknesses and smooth chips are formed. The governing parameters are tool geometry, which is principally the wedge angle, and the material properties of elastic modulus, yield stress and fracture toughness. Friction can also be important. It is demonstrated that the cutting process may be quantified via these parameters, which could be useful in the study of cutting in biology. PMID:27274798

  17. Algorithms and Algorithmic Languages.

    ERIC Educational Resources Information Center

    Veselov, V. M.; Koprov, V. M.

    This paper is intended as an introduction to a number of problems connected with the description of algorithms and algorithmic languages, particularly the syntaxes and semantics of algorithmic languages. The terms "letter, word, alphabet" are defined and described. The concept of the algorithm is defined and the relation between the algorithm and…

  18. Varied line spacing plane holographic grating recorded by using uniform line spacing plane gratings.

    PubMed

    Qing, Ling; Gang, Wu; Bin, Liu; Qiuping, Wang

    2006-07-20

    Uniform line spacing plane gratings are introduced into a recording system to generate aspherical wavefronts for recording varied line spacing plane holographic gratings. Analytical expressions of groove parameters are derived to the fourth order. A ray-tracing validation algorithm is provided based on Fermat's principle and a local search method. The recording parameters are optimized to record a varied line spacing plane holographic grating with the aid of derived analytical expressions. A design example demonstrates the exactness of the analytical expressions and the superiority of recording optics with auxiliary gratings. PMID:16826244

  19. Fourier plane imaging microscopy

    SciTech Connect

    Dominguez, Daniel Peralta, Luis Grave de; Alharbi, Nouf; Alhusain, Mdhaoui; Bernussi, Ayrton A.

    2014-09-14

    We show how the image of an unresolved photonic crystal can be reconstructed using a single Fourier plane (FP) image obtained with a second camera that was added to a traditional compound microscope. We discuss how Fourier plane imaging microscopy is an application of a remarkable property of the obtained FP images: they contain more information about the photonic crystals than the images recorded by the camera commonly placed at the real plane of the microscope. We argue that the experimental results support the hypothesis that surface waves, contributing to enhanced resolution abilities, were optically excited in the studied photonic crystals.

  20. Cutting hospital costs without cutting staff.

    PubMed

    Ortiz, John P

    2011-10-01

    A hospital that is seeking ways to cut costs without compromising care should resist the temptation to lay off staff and instead make it a priority to improve efficiencies. This approach requires a formal program to identify and analyze all of the hospital's processes. The focus of the analysis should be to determine which activities are being performed efficiently, which are being performed inefficiently, and which are unnecessary. This effort will achieve the greatest success if it is customer-centric. PMID:22053641

  1. INTERNAL CUTTING DEVICE

    DOEpatents

    Russell, W.H. Jr.

    1959-06-30

    A device is described for removing material from the interior of a hollow workpiece so as to form a true spherical internal surface in a workpiece, or to cut radial slots of an adjustable constant depth in an already established spherical internal surface. This is accomplished by a spring loaded cutting tool adapted to move axially wherein the entire force urging the tool against the workpiece is derived from the spring. Further features of importance involve the provision of a seal between the workpiece and the cutting device and a suction device for carrying away particles of removed material.

  2. Position-space cuts for Wilson line correlators

    NASA Astrophysics Data System (ADS)

    Laenen, Eric; Larsen, Kasper J.; Rietkerk, Robbert

    2015-07-01

    We further develop the formalism for taking position-space cuts of eikonal diagrams introduced in ref. [1]. These cuts are applied directly to the position-space representation of any such diagram and compute its discontinuity to the leading order in the dimensional regulator. We provide algorithms for computing the position-space cuts and apply them to several two- and three-loop eikonal diagrams, finding agreement with results previously obtained in the literature. We discuss a non-trivial interplay between the cutting prescription and non-Abelian exponentiation. We furthermore discuss the relation of the imaginary part of the cusp anomalous dimension to the static interquark potential.

  3. Automatic registration method for multisensor datasets adopted for dimensional measurements on cutting tools

    NASA Astrophysics Data System (ADS)

    Shaw, L.; Ettl, S.; Mehari, F.; Weckenmann, A.; Häusler, G.

    2013-04-01

    Multisensor systems with optical 3D sensors are frequently employed to capture complete surface information by measuring workpieces from different views. During coarse and fine registration the resulting datasets are afterward transformed into one common coordinate system. Automatic fine registration methods are well established in dimensional metrology, whereas there is a deficit in automatic coarse registration methods. The advantage of a fully automatic registration procedure is twofold: it enables a fast and contact-free alignment and further a flexible application to datasets of any kind of optical 3D sensor. In this paper, an algorithm adapted for a robust automatic coarse registration is presented. The method was originally developed for the field of object reconstruction or localization. It is based on a segmentation of planes in the datasets to calculate the transformation parameters. The rotation is defined by the normals of three corresponding segmented planes of two overlapping datasets, while the translation is calculated via the intersection point of the segmented planes. First results have shown that the translation is strongly shape dependent: 3D data of objects with non-orthogonal planar flanks cannot be registered with the current method. In the novel supplement for the algorithm, the translation is additionally calculated via the distance between centroids of corresponding segmented planes, which results in more than one option for the transformation. A newly introduced measure considering the distance between the datasets after coarse registration evaluates the best possible transformation. Results of the robust automatic registration method are presented on the example of datasets taken from a cutting tool with a fringe-projection system and a focus-variation system. The successful application in dimensional metrology is proven with evaluations of shape parameters based on the registered datasets of a calibrated workpiece.

  4. Testing Of Choiced Ceramics Cutting Tools At Irregular Interrupted Cut

    NASA Astrophysics Data System (ADS)

    Kyncl, Ladislav; Malotová, Šárka; Nováček, Pavel; Nicielnik, Henryk; Šoková, Dagmar; Hemžský, Pavel; Pitela, David; Holubjak, Jozef

    2015-12-01

    This article discusses the test of removable ceramic cutting inserts during machining irregular interrupted cut. Tests were performed on a lathe, with the preparation which simulated us the interrupted cut. By changing the number of plates mounted in a preparation it simulate us a regular or irregular interrupted cut. When with four plates it was regular interrupted cut, the remaining three variants were already irregular cut. It was examined whether it will have the irregular interrupted cutting effect on the insert and possibly how it will change life of inserts during irregular interrupted cut (variable delay between shocks).

  5. Measuring method of CCD installation verticality based on own system of intelligent laser cutting machine

    NASA Astrophysics Data System (ADS)

    Zhong, Ping; Lu, Hongbo; Liu, Fuguo; Chen, Ziyuan; He, Pan; Jiang, Xueshi

    2016-01-01

    The installation verticality between the optical axis of CCD and the working plane of intelligent laser cutting machine is one of the most important factors in determining image quality of the processed object which comes from computer vision system. In this paper, an innovative method is proposed which can make it possible to use the equipment of own system of intelligent laser cutting machine to detect installation verticality between the optical axis of CCD and the working plane. Experimental results show that the method presented in this paper is a feasible solution for measuring the installation verticality between the optical axis of CCD and the working plane of intelligent laser cutting machine.

  6. Improved virtual surgical cutting based on physical experiments.

    PubMed

    Lim, Yi-Je; Jones, Daniel B; De, Suvranu

    2005-01-01

    Simulation of surgical cutting is one of the most challenging tasks in the development of a surgery simulator. Changes in topology during simulation make any precomputed data meaningless. Moreover, the process is nonlinear and given the complexity of soft tissue mechanics, the underlying physics is not well understood. Therefore, fully realistic procedures for the simulation of surgical cutting at real time rates on single processor machines is possibly out of reach. We developed a geometry-based algorithm that is capable of simulating progressive cutting without increasing the number of primitives and have coupled it to a meshfree physically based simulation scheme. In this paper we enhance a geometrically efficient cutting algorithm by including physical information from actual cutting experiments. PMID:15718749

  7. Cuts, Scratches, and Scrapes

    MedlinePlus

    ... to make sure the animal didn't have rabies. Certain cuts or bites could lead to a ... purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995- The Nemours Foundation. All ...

  8. Cut without Killing.

    ERIC Educational Resources Information Center

    Black, Susan

    1991-01-01

    The zero-based curriculum model can help school boards and administrators make decisions about what to keep and what to cut. All instructional programs are ranked and judged in categories ranging from required to optional. (MLF)

  9. Structure of AlSi-SiC composite foams surface formed by mechanical and thermal cutting

    NASA Astrophysics Data System (ADS)

    Krajewski, Sławomir; Nowacki, Jerzy

    2015-02-01

    The article presents the geometric structure of AlSi-SiC composite foam surface after thermal, mechanical and erosive cutting with regards to its subsequent practical applications. In stereometric measurements of foam surfaces, confocal microscopy was suggested as a method fit for measuring surfaces of high discontinuity ratio that results from porosity. Basic quality parameters of cutting plane were characterised, and technical as well as methodological problems deriving from atypical porous structure of metallic foams were identified. On the basis of the results obtained, the influence of cutting methods on the geometric parameters of foam plane was established, and most favourable cutting conditions were determined.

  10. Material for Fast Cutting

    NASA Technical Reports Server (NTRS)

    Perez, A.

    1986-01-01

    New material for cutting tools increases productivity of machining processes. Material, called Iscanite (or equivalent), based on silicon nitride contains more than 90 percent silicon. Combines impact resistance close to that of coated carbides with heat and wear resistance close to those of aluminum oxide ceramics. Material used for cutting on old or new machine tools and makes it possible to exploit fully power and speed of machine.

  11. Laser cutting system

    SciTech Connect

    Dougherty, Thomas J

    2015-03-03

    A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

  12. 2. VIEW SOUTH, INCLINE PLANE CAR, INCLINE PLANE TRACK, UPPER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW SOUTH, INCLINE PLANE CAR, INCLINE PLANE TRACK, UPPER STATION. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  13. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou

    2000-01-30

    This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.

  14. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-01-30

    This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  15. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-07-30

    This is the fourth quarterly progress report for Year-3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between April 1, 2002 and June 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)''; (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions''; (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''; (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  16. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-04-30

    This is the third quarterly progress report for Year 3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between Jan. 1, 2002 and Mar. 31, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop, progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); and (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  17. A Gradient Descent Approximation for Graph Cuts

    NASA Astrophysics Data System (ADS)

    Yildiz, Alparslan; Akgul, Yusuf Sinan

    Graph cuts have become very popular in many areas of computer vision including segmentation, energy minimization, and 3D reconstruction. Their ability to find optimal results efficiently and the convenience of usage are some of the factors of this popularity. However, there are a few issues with graph cuts, such as inherent sequential nature of popular algorithms and the memory bloat in large scale problems. In this paper, we introduce a novel method for the approximation of the graph cut optimization by posing the problem as a gradient descent formulation. The advantages of our method is the ability to work efficiently on large problems and the possibility of convenient implementation on parallel architectures such as inexpensive Graphics Processing Units (GPUs). We have implemented the proposed method on the Nvidia 8800GTS GPU. The classical segmentation experiments on static images and video data showed the effectiveness of our method.

  18. Image plane sweep volume illumination.

    PubMed

    Sundén, Erik; Ynnerman, Anders; Ropinski, Timo

    2011-12-01

    In recent years, many volumetric illumination models have been proposed, which have the potential to simulate advanced lighting effects and thus support improved image comprehension. Although volume ray-casting is widely accepted as the volume rendering technique which achieves the highest image quality, so far no volumetric illumination algorithm has been designed to be directly incorporated into the ray-casting process. In this paper we propose image plane sweep volume illumination (IPSVI), which allows the integration of advanced illumination effects into a GPU-based volume ray-caster by exploiting the plane sweep paradigm. Thus, we are able to reduce the problem complexity and achieve interactive frame rates, while supporting scattering as well as shadowing. Since all illumination computations are performed directly within a single rendering pass, IPSVI does not require any preprocessing nor does it need to store intermediate results within an illumination volume. It therefore has a significantly lower memory footprint than other techniques. This makes IPSVI directly applicable to large data sets. Furthermore, the integration into a GPU-based ray-caster allows for high image quality as well as improved rendering performance by exploiting early ray termination. This paper discusses the theory behind IPSVI, describes its implementation, demonstrates its visual results and provides performance measurements. PMID:22034331

  19. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mengjiao Yu; Ramadan Ahmed; Mark Pickell; Len Volk; Lei Zhou; Zhu Chen; Aimee Washington; Crystal Redden

    2003-09-30

    The Quarter began with installing the new drill pipe, hooking up the new hydraulic power unit, completing the pipe rotation system (Task 4 has been completed), and making the SWACO choke operational. Detailed design and procurement work is proceeding on a system to elevate the drill-string section. The prototype Foam Generator Cell has been completed by Temco and delivered. Work is currently underway to calibrate the system. Literature review and preliminary model development for cuttings transportation with polymer foam under EPET conditions are in progress. Preparations for preliminary cuttings transport experiments with polymer foam have been completed. Two nuclear densitometers were re-calibrated. Drill pipe rotation system was tested up to 250 RPM. Water flow tests were conducted while rotating the drill pipe up to 100 RPM. The accuracy of weight measurements for cuttings in the annulus was evaluated. Additional modifications of the cuttings collection system are being considered in order to obtain the desired accurate measurement of cuttings weight in the annular test section. Cutting transport experiments with aerated fluids are being conducted at EPET, and analyses of the collected data are in progress. The printed circuit board is functioning with acceptable noise level to measure cuttings concentration at static condition using ultrasonic method. We were able to conduct several tests using a standard low pass filter to eliminate high frequency noise. We tested to verify that we can distinguish between different depths of sand in a static bed of sand. We tested with water, air and a mix of the two mediums. Major modifications to the DTF have almost been completed. A stop-flow cell is being designed for the DTF, the ACTF and Foam Generator/Viscometer which will allow us to capture bubble images without the need for ultra fast shutter speeds or microsecond flash system.

  20. a Unified Blending Framework for Panorama Completion via Graph Cuts

    NASA Astrophysics Data System (ADS)

    Chen, Kai; Yao, Jian; Xia, Menghan; Gui, Xinyuan; Lu, Xiaohu; Li, Li

    2016-06-01

    In this paper, we propose a unified framework for efficiently completing streetview and indoor 360° panoramas due to the lack of bottom areas caused by the occlusion of the acquisition platform. To greatly reduce the severe distortion at the bottom of the panorama, we first reproject it onto the ground perspective plane containing the whole occluded region to be completed. Then, we formulate the image completion problem in an improved graph cuts optimization framework based on the statistics of similar patches by strengthening the boundary constraints. To further eliminate image luminance differences and color deviations and conceal geometrical parallax among the optimally selected patches for completion, we creatively apply a multi-bland image blending algorithm for perfect image mosaicking from the completed patches and the originally reprojected image. Finally, we back-project the completed and blended ground perspective image into the cylindrical-projection panorama followed by a simple feathering to further reduce artifacts in the panorama. Experimental results on some representative non-panoramic images and streetview and indoor panoramas demonstrate the efficiency and robustness of the proposed method even in some challenging cases.

  1. Determination of cut front position in laser cutting

    NASA Astrophysics Data System (ADS)

    Pereira, M.; Thombansen, U.

    2016-07-01

    Laser cutting has a huge importance to manufacturing industry. Laser cutting machines operate with fixed technological parameters and this does not guarantee the best productivity. The adjustment of the cutting parameters during operation can improve the machine performance. Based on a coaxial measuring device it is possible to identify the cut front position during the cutting process. This paper describes the data analysis approach used to determine the cut front position for different feed rates. The cut front position was determined with good resolution, but improvements are needed to make the whole process more stable.

  2. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira

    2000-10-30

    This is the first quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between July 14, 2000 and September 30, 2000. This report presents information on the following specific tasks: (a) Progress in Advanced Cuttings Transport Facility design and development (Task 2), (b) Progress on research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress on research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress on research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress on research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Initiate research on project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Progress on instrumentation tasks to measure: Cuttings concentration and distribution (Tasks 11), and Foam properties (Task 12), (h) Initiate a comprehensive safety review of all flow-loop components and operational procedures. Since the previous Task 1 has been completed, we will now designate this new task as: (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  3. SNAP focal plane

    SciTech Connect

    Lampton, Michael L.; Kim, A.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Berkovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro,R.; Ealet, A.; Ellis, R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland, S.E.; Huterer, D.; Karcher, A.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder,E.V.; Loken, S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto, E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.

    2002-07-29

    The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square-degree field sensitive in the visible and near-infrared wavelength regime. We describe the requirements for the instrument suite and the evolution of the focal plane design to the present concept in which all the instrumentation--visible and near-infrared imagers, spectrograph, and star guiders--share one common focal plane.

  4. Plane wave imaging using phased array

    NASA Astrophysics Data System (ADS)

    Volker, Arno

    2014-02-01

    Phased arrays are often used for rapid inspections. Phased arrays can be used to synthesize different wave fronts. For imaging, focused wave fronts are frequently used. In order to build an image, the phased array has to be fired multiple times at the same location. Alternatively, different data acquisition configurations can be designed in combination with an imaging algorithm. The objective of this paper is to use the minimal amount of data required to construct an image. If a plane wave is synthesized, the region of interest is illuminated completely. For plane wave synthesis, all elements in the phase array are fired. This ensures a good signal to noise ratio. Imaging can be performed efficiently with a mapping algorithm in the wavenumber domain. The algorithm involves only two Fourier transforms and can therefore be extremely fast. The obtained resolution is comparable to conventional imaging algorithms. This work investigates the potential and limitations of this mapping algorithm on simulated data. With this approach, frame rates of more than 1 kHz can be achieved.

  5. Cutting Guide for Fibrous Sheets

    NASA Technical Reports Server (NTRS)

    Warren, A., D.

    1985-01-01

    Tool facilitates repetitive cutting of fibrous sheets. Flexible aluminum tape allows metal strips folded back on themselves, exposing fresh material for cutting. More than one strip folded back, and cutting width therefore increased in multiples of strip width. Developed for cutting strips of alumina-fiber matting, tool also used on such materials as felts, textiles, and sheet metals.

  6. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Len Volk; Mark Pickell; Evren Ozbayoglu; Barkim Demirdal; Paco Vieira; Affonso Lourenco

    1999-10-15

    This report includes a review of the progress made in ACTF Flow Loop development and research during 90 days pre-award period (May 15-July 14, 1999) and the following three months after the project approval date (July15-October 15, 1999) The report presents information on the following specific subjects; (a) Progress in Advanced Cuttings Transport Facility design and development, (b) Progress report on the research project ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress report on the research project ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress report on the research project ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress report on the research project ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Progress report on the instrumentation tasks (Tasks 11 and 12) (g) Activities towards technology transfer and developing contacts with oil and service company members.

  7. Radial cutting torch

    SciTech Connect

    Robertson, M.C.

    1997-01-08

    The project`s aim is to complete development of the Radial Cutting Torch, a pyrotechnic cutter, for use in all downhole tubular cutting operations in the petroleum industry. Project objectives are to redesign and pressure test nozzle seals to increase product quality, reliability, and manufacturability; improve the mechanical anchor to increase its temperature tolerance and its ability to function in a wider variety of wellbore fluids; and redesign and pressure test the RCT nozzle for operation at pressures from 10 to 20 ksi. The proposal work statement is included in the statement of work for the grant via this reference.

  8. Cutting assembly. [Patent application

    DOEpatents

    Treuhaft, M.B.; Oser, M.S.

    1981-06-25

    A mining auger comprises a cutting head carried at one end of a tubular shaft and a plurality of wall segments which in a first position thereof are disposed side by side around said shaft and in a second position thereof are disposed oblique to said shaft. A vane projects outwardly from each wall segment. When the wall segments are in their first position, the vanes together form a substantially continuous helical wall. A cutter is mounted on the peripheral edge of each of the vanes. When the wall segments are in their second position, the cutters on the vanes are disposed radially outward from the perimeter of the cutting head.

  9. Beamlet focal plane diagnostic

    SciTech Connect

    Caird, J.A.; Nielsen, N.D.; Patton, H.G.; Seppala, L.G.; Thompson, C.E.; Wegner, P.J.

    1996-12-01

    This paper describes the major optical and mechanical design features of the Beamlet Focal Plane Diagnostic system as well as measurements of the system performance, and typical data obtained to date. We also discuss the NIF requirements on the focal spot that we are interested in measuring, and some of our plans for future work using this system.

  10. Geometrical analysis of circular-cut spiral bevel gears

    NASA Technical Reports Server (NTRS)

    Huston, R. L.

    1983-01-01

    Geometrical studies of circular cut spiral bevel gears are reported. Tooth profile changes heel to toe are studied in the transverse plane. Pressure angle changes are determined. The radiuses of curvature of the tooth surfaces generated by various cutter profiles are also determined. The consequences of cutter profile changes are explored. Crown gears are emphasized and the implications for conical gears are discussed.

  11. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Troy Reed; Ergun Kuru

    2004-09-30

    The Advanced Cuttings Transport Study (ACTS) was a 5-year JIP project undertaken at the University of Tulsa (TU). The project was sponsored by the U.S. Department of Energy (DOE) and JIP member companies. The objectives of the project were: (1) to develop and construct a new research facility that would allow three-phase (gas, liquid and cuttings) flow experiments under ambient and EPET (elevated pressure and temperature) conditions, and at different angle of inclinations and drill pipe rotation speeds; (2) to conduct experiments and develop a data base for the industry and academia; and (3) to develop mechanistic models for optimization of drilling hydraulics and cuttings transport. This project consisted of research studies, flow loop construction and instrumentation development. Following a one-year period for basic flow loop construction, a proposal was submitted by TU to the DOE for a five-year project that was organized in such a manner as to provide a logical progression of research experiments as well as additions to the basic flow loop. The flow loop additions and improvements included: (1) elevated temperature capability; (2) two-phase (gas and liquid, foam etc.) capability; (3) cuttings injection and removal system; (4) drill pipe rotation system; and (5) drilling section elevation system. In parallel with the flow loop construction, hydraulics and cuttings transport studies were preformed using drilling foams and aerated muds. In addition, hydraulics and rheology of synthetic drilling fluids were investigated. The studies were performed under ambient and EPET conditions. The effects of temperature and pressure on the hydraulics and cuttings transport were investigated. Mechanistic models were developed to predict frictional pressure loss and cuttings transport in horizontal and near-horizontal configurations. Model predictions were compared with the measured data. Predominantly, model predictions show satisfactory agreements with the measured data. As a

  12. The Principle and Applications of Multi-Plane Separation for Balancing Machines

    NASA Astrophysics Data System (ADS)

    Kang, Y.; Sheen, G.-J.; Tang, P.-H.

    1997-11-01

    Two-plane separation is a conventional technique of balancing machines for rigid rotors such that each sensor measures the separated effects of equivalent imbalances in two planes. However, some complex rigid rotors such as multicylinder crankshafts need to be balanced by multi-plane correction for reducing mass concentration at two planes. This study verifies the principle of plane separation by using an exact-point influence coefficient approach. From the analysis a generalized algorithm of multiplane separation can be developed. Thus, an unlimited technique of plane separation is provided to improve balancing machines for complex rotors which have several planes in need of correction.

  13. Investigation of formation mechanisms of chips in orthogonal cutting process

    NASA Astrophysics Data System (ADS)

    Ma, W.

    2012-08-01

    This work investigates the formation mechanisms of chips in orthogonal cutting of mild steel and the transformation conditions between various morphology chips. It is supposed that the modeling material follows the Johnson-Cook constitutive model. In orthogonal cutting process, both the plastic flow and the instability behaviors of chip materials are caused by the plane strain loadings. Therefore, the general instability behaviors of materials in plane strain state are first analyzed with linear perturbation method and a universal instability criterion is established. Based on the analytical results, the formation mechanisms of chips and the transformation conditions between continuous and serrated chips are further studied by instability phase diagram method. The results show that the chip formation strongly depends on the intensity ratios between shear and normal stresses. The ratios of dissipative rates of plastic work done by compression and shear stresses govern the transformation from continuous to serrated chips. These results are verified by the numerical simulations on the orthogonal cutting process.

  14. Cuts endanger more services.

    PubMed

    Evans, Nick

    2016-06-01

    WHEN BARNSLEY council put out its tender for the 0-19 service last autumn, it laid down strict criteria. A ceiling of £4.8 million a year was put on any bids for the service, which incorporates school nursing teams and health visitors. That represented a cut of more than £1 million on the existing contract. PMID:27266736

  15. A Cut below

    ERIC Educational Resources Information Center

    Lum, Lydia

    2010-01-01

    Today, thousands of California students worry about vanishing college affordability and access, especially for historically under-represented and marginalized populations. The author reports on how students and faculty throughout California are grappling with the effects of draconian state cuts to postsecondary education that have topped more than…

  16. Think before You Cut

    ERIC Educational Resources Information Center

    Pettifor, Ann

    2010-01-01

    With the main political parties set on reducing public spending, one might be forgiven for supposing that "savage" cuts are the only way forward. However, the author believes there are alternatives, and that is why public education about the financial system is so important. Today, UK is trying to clear up a mess--a mess made by the greedy and…

  17. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Len Volk; Mark Pickell; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Neelima Godugu; Sri Suresh Kumar Thiroveedhula

    2000-04-30

    ACTS flow loop is now operational under elevated pressure and temperature. Currently, experiments with water under pressure and temperature are being conducted. Based on the analysis of Fann 70 data, empirical correlations defining the shear stress as a function of temperature, pressure and the shear rate have been developed for Petrobras synthetic drilling fluids. PVT equipment has been modified for testing Synthetic drilling fluids. Initial calibration tests have been conducted by using water. Currently, the base oil of the Petrobras synthetic drilling fluid is being tested. Foam flow experiments have been conducted. Currently, more experiments are being conducted while data are being analyzed to characterize the rheology of the foam. Cuttings transport experiments have been conducted using air, water and cuttings. Preliminary results have shown that it may not be possible to avoid cuttings bed deposition under any practical combination of air and water flow rates. Foam stability analyses have been conducted. Effects of salt and oil concentration on the foam stability have been investigated. A software for controlling the data sampling and data storage during cuttings monitoring process have been developed.

  18. Electron beam cutting

    DOEpatents

    Mochel, Margaret E.; Humphreys, Colin J.

    1985-04-02

    A method for the cutting of holes 20 Angstroms in diameter, or lines 20 Angstroms wide in a material having positive ionic conduction by the use of a focused electron probe is described. The holes and lines are stable under ambient conditions.

  19. Electron beam cutting

    DOEpatents

    Mochel, M.E.; Humphreys, C.J.

    1985-04-02

    A method for the cutting of holes 20 Angstroms in diameter, or lines 20 Angstroms wide in a material having positive ionic conduction by the use of a focused electron probe is described. The holes and lines are stable under ambient conditions. 2 figs.

  20. Classroom Cut Ups

    ERIC Educational Resources Information Center

    Lord, Stacy

    2011-01-01

    Discovering identity can be a lifelong challenge for some people, while others seem to figure it out right away. During the middle school years, finding one's identity can be a daunting task. Most students will spend a considerable amount of time during these middle years looking for it. This lesson on cut-paper self-portraits lets students delve…

  1. Collaborating To Cut Costs.

    ERIC Educational Resources Information Center

    Strosnider, Kim

    1998-01-01

    Private colleges across the country are collaborating to cut costs, streamline services, and increase efficiency. An ambitious Ohio project, involving 35 colleges, to redesign business operations hopes to save $20-25 million. Other efforts include joint classes using interactive television, shared library resources, cross-registration, jointly…

  2. Kids Who Cut.

    ERIC Educational Resources Information Center

    Coy, Doris Rhea; Simpson, Chris

    2002-01-01

    Regardless of whether it is cutting, burning or some other form of self-harm, self-injury is a serious problem requiring serious solutions. This article reviews the various types of self-harm, descriptions of self-mutilators, common myths about self-mutilation, and effective treatment methods. (GCP)

  3. Cutting Cakes Carefully

    ERIC Educational Resources Information Center

    Hill, Theodore P.; Morrison, Kent E.

    2010-01-01

    This paper surveys the fascinating mathematics of fair division, and provides a suite of examples using basic ideas from algebra, calculus, and probability which can be used to examine and test new and sometimes complex mathematical theories and claims involving fair division. Conversely, the classical cut-and-choose and moving-knife algorithms…

  4. The tail plane

    NASA Technical Reports Server (NTRS)

    Munk, Max M

    1923-01-01

    This report deals with the calculation of the equilibrium, statistical stability, and damping of the tail plane. The author has simplified the present theory of longitudinal stability for the particular purpose of obtaining one definite coefficient characteristics of the effect of the tail plane. This coefficient is obtained by substituting certain aerodynamic characteristics and some dimensions of the airplane in a comparatively simple mathematical expression. Care has been taken to confine all aerodynamical information necessary for the calculation of the coefficient to the well-known curves representing the qualities of the wing section. This is done by making use of the present results of modern aerodynamics. All formulas and relations necessary for the calculation are contained in the paper. They give in some cases only an approximation of the real values. An example of calculation is added in order to illustrate the application of the method. The coefficient indicates not only whether the effect of the tail plane is great enough, but also whether it is not too great. It appears that the designer has to avoid a certain critical length of the fuselage, which inevitably gives rise to periodical oscillations of the airplane. The discussion also shows the way and in what direction to carry out experimental work.

  5. Circular Vibration Planing of Inconel 718

    NASA Astrophysics Data System (ADS)

    Hettiarachchi, Nandita Kalyanakumara; Moriwaki, Toshimichi; Shibasaka, Toshiro; Nakamoto, Keiichi

    Circular vibration milling (CVM) is achieved by vibrating a milling cutter about the machine tool spindle axis in a circular path, in addition to its rotary motion. CVM has been proven capable of producing better surface finishes on difficult to cut materials. However, the CVM process is far slower than conventional milling process. In circular vibration planing (CVP) process, the cutting tool is clamped without rotation and fed at a speed comparable to the feed speed of conventional milling. By superimposing circular vibration motion, necessary cutting speed could be achieved keeping the feed speed at realistic values. Inconel 718 was machined by CVP and conventional milling at a similar feed rate. It was observed that CVP could reduce tool wear and hence produce better surface finishes than conventional milling. A geometric simulation showed a major difference between uncut chip shapes of the two processes. The difference of uncut chip shapes suggests that in CVP process, less rubbing occurs between tool flank face and work before the tool penetrates in to the work to form a chip. The reduced rubbing of the flank face is proposed as the reson for reduced tool wear in CVP when compared with conventional milling.

  6. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-04-30

    Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have

  7. Synthesis of fully continuous phase screens for tailoring the focal plane irradiance profiles

    SciTech Connect

    Dixit, S.; Feit, M.

    1996-04-26

    We present an iterative procedure for constructing fully continuous phase screens for tailoring the focal plane intensity distributions. This algorithm alleviates the stagnations experienced in the application of the Gerchberg-Saxton algorithm with a random initial phase screen and leads to efficient distribution of the incident energy into the desired focal plane profile.

  8. A Comparison of Numerical and Analytical Radiative-Transfer Solutions for Plane Albedo of Natural Waters

    EPA Science Inventory

    Three numerical algorithms were compared to provide a solution of a radiative transfer equation (RTE) for plane albedo (hemispherical reflectance) in semi-infinite one-dimensional plane-parallel layer. Algorithms were based on the invariant imbedding method and two different var...

  9. Laser cutting nozzle

    DOEpatents

    Ramos, T.J.

    1982-09-30

    A laser cutting nozzle for use with a laser cutting apparatus directing a focused beam to a spot on a work piece. The nozzle has a cylindrical body with a conical tip which together have a conically shaped hollow interior with the apex at a small aperture through the tip. The conical hollow interior is shaped to match the profile of the laser beam, at full beamwidth, which passes through the nozzle to the work piece. A plurality of gas inlet holes extend through the body to the hollow interior and are oriented to produce a swirling flow of gas coaxially through the nozzle and out the aperture, aligned with the laser beam, to the work piece.

  10. Laser cutting nozzle

    DOEpatents

    Ramos, Terry J.

    1984-01-01

    A laser cutting nozzle for use with a laser cutting apparatus directing a focused beam to a spot on a work piece. The nozzle has a cylindrical body with a conical tip which together have a conically shaped hollow interior with the apex at a small aperture through the tip. The conical hollow interior is shaped to match the profile of the laser beam, at full beamwidth, which passes through the nozzle to the work piece. A plurality of gas inlet holes extend through the body to the hollow interior and are oriented to produce a swirling flow of gas coaxially through the nozzle and out the aperture, aligned with the laser beam, to the work piece. BACKGROUND OF THE INVENTION

  11. Skylab Exhibit Ribbon Cutting

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A metal strap became tangled over one of the folded solar array panels when Skylab lost its micro meteoroid shield during its launch. Cutters like the ones used to free the solar array were used to cut the ribbon opening to the public a new full-scale Skylab cluster exhibit at the Alabama Space and Rocket Center in Huntsville, Alabama. Wielding the cutters are (left to right): Alabama Senator James B. Allen; Marshall Space Flight Center director, Dr. William R. Lucas, Huntsville Mayor, Joe Davis; Madison County Commission Chairman, James Record (standing behind Mayor Davis); and chairman of the Alabama Space Science Exhibit Commission, Jack Giles. Astronauts Conrad and Kerwin used the same type of tool in Earth orbit to cut the aluminum strap which jammed the Skylab solar array.

  12. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Neelima Godugu

    2000-07-30

    ACTS flow loop is now operational under elevated pressure and temperature. Currently, experiments with synthetic based drilling fluids under pressure and temperature are being conducted. Based on the analysis of Fann 70 data, empirical correlations defining the shear stress as a function of temperature, pressure and the shear rate have been developed for Petrobras synthetic drilling fluids. PVT equipment has been modified for testing Synthetic oil base drilling fluids. PVT tests with Petrobras Synthetic base mud have been conducted and results are being analyzed Foam flow experiments have been conducted and the analysis of the data has been carried out to characterize the rheology of the foam. Comparison of pressure loss prediction from the available foam hydraulic models and the test results has been made. Cuttings transport experiments in horizontal annulus section have been conducted using air, water and cuttings. Currently, cuttings transport tests in inclined test section are being conducted. Foam PVT analysis tests have been conducted. Foam stability experiments have also been conducted. Effects of salt and oil concentration on the foam stability have been investigated. Design of ACTS flow loop modification for foam and aerated mud flow has been completed. A flow loop operation procedure for conducting foam flow experiments under EPET conditions has been prepared Design of the lab-scale flow loop for dynamic foam characterization and cuttings monitoring instrumentation tests has been completed. The construction of the test loop is underway. As part of the technology transport efforts, Advisory Board Meeting with ACTS-JIP industry members has been organized on May 13, 2000.

  13. Manual bamboo cutting tool.

    PubMed

    Bezerra, Mariana Pereira; Correia, Walter Franklin Marques; da Costa Campos, Fabio Ferreira

    2012-01-01

    The paper presents the development of a cutting tool guide, specifically for the harvest of bamboo. The development was made based on precepts of eco-design and ergonomics, for prioritizing the physical health of the operator and the maintenance of the environment, as well as meet specific requirements of bamboo. The main goal is to spread the use of bamboo as construction material, handicrafts, among others, from a handy, easy assembly and material available tool. PMID:22317613

  14. Materials, devices, techniques, and applications for Z-plane focal plane array technology II; Proceedings of the Meeting, San Diego, CA, July 12, 13, 1990

    NASA Astrophysics Data System (ADS)

    Carson, John C.

    1990-11-01

    Various papers on materials, devices, techniques, and applications for X-plane focal plane array technology are presented. Individual topics addressed include: application of Z-plane technology to the remote sensing of the earth from GEO, applications of smart neuromorphic focal planes, image-processing of Z-plane technology, neural network Z-plane implementation with very high interconnection rates, using a small IR surveillance satellite for tactical applications, establishing requirements for homing applications, Z-plane technology. Also discussed are: on-array spike suppression signal processing, algorithms for on-focal-plane gamma circumvention and time-delay integration, current HYMOSS Z-technology, packaging of electrons for on- and off-FPA signal processing, space/performance qualification of tape automated bonded devices, automation in tape automated bonding, high-speed/high-volume radiometric testing of Z-technology focal planes, 128-layer HYMOSS-module fabrication issues, automation of IRFPA production processes.

  15. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-07-30

    This Quarter has been divided between running experiments and the installation of the drill-pipe rotation system. In addition, valves and piping were relocated, and three viewports were installed. Detailed design work is proceeding on a system to elevate the drill-string section. Design of the first prototype version of a Foam Generator has been finalized, and fabrication is underway. This will be used to determine the relationship between surface roughness and ''slip'' of foams at solid boundaries. Additional cups and rotors are being machined with different surface roughness. Some experiments on cuttings transport with aerated fluids have been conducted at EPET. Theoretical modeling of cuttings transport with aerated fluids is proceeding. The development of theoretical models to predict frictional pressure losses of flowing foam is in progress. The new board design for instrumentation to measure cuttings concentration is now functioning with an acceptable noise level. The ultrasonic sensors are stable up to 190 F. Static tests with sand in an annulus indicate that the system is able to distinguish between different sand concentrations. Viscometer tests with foam, generated by the Dynamic Test Facility (DTF), are continuing.

  16. Reagan Administration Prepares Budget Cuts.

    ERIC Educational Resources Information Center

    Norman, Colin

    1981-01-01

    Describes tentative federal budget cuts affecting science education in the National Science Foundation, National Aeronautics and Space Administration, Department of Energy, National Institutes of Health, and the specific areas these budget cuts will affect. (DS)

  17. Dealing with Cuts (For Parents)

    MedlinePlus

    ... pus. For Bleeding From a Large Cut or Laceration: Wash the wound thoroughly with water. This will ... immediate medical attention for all large cuts or lacerations, or if: you're unable to stop the ...

  18. Method for 3D noncontact measurements of cut trees package area

    NASA Astrophysics Data System (ADS)

    Knyaz, Vladimir A.; Vizilter, Yuri V.

    2001-02-01

    Progress in imaging sensors and computers create the background for numerous 3D imaging application for wide variety of manufacturing activity. Many demands for automated precise measurements are in wood branch of industry. One of them is the accurate volume definition for cut trees carried on the truck. The key point for volume estimation is determination of the front area of the cut tree package. To eliminate slow and inaccurate manual measurements being now in practice the experimental system for automated non-contact wood measurements is developed. The system includes two non-metric CCD video cameras, PC as central processing unit, frame grabbers and original software for image processing and 3D measurements. The proposed method of measurement is based on capturing the stereo pair of front of trees package and performing the image orthotranformation into the front plane. This technique allows to process transformed image for circle shapes recognition and calculating their area. The metric characteristics of the system are provided by special camera calibration procedure. The paper presents the developed method of 3D measurements, describes the hardware used for image acquisition and the software realized the developed algorithms, gives the productivity and precision characteristics of the system.

  19. Fourier plane image amplifier

    DOEpatents

    Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.

    1995-12-12

    A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.

  20. Fourier plane image amplifier

    DOEpatents

    Hackel, Lloyd A.; Hermann, Mark R.; Dane, C. Brent; Tiszauer, Detlev H.

    1995-01-01

    A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.

  1. Mosaic Focal Plane Development

    NASA Astrophysics Data System (ADS)

    Mason, David L.; Horner, Scott D.; Aamodt, Earl K.

    2002-12-01

    Advances in systems engineering, applied sciences, and manufacturing technologies have enabled the development of large ground based and spaced based astronomical instruments having a large Field of View (FOV) to capture a large portion of the universe in a single image. A larger FOV can be accomplished using light weighted optical elements, improved support structures, and the development of mosaic Focal Plane Assemblies (mFPA). A mFPA designed for astronomy can use multiple Charged Coupled Devices (CCD) mounted onto a single camera baseplate integrated at the instrument plane of focus. Examples of current, or proposed, missions utilizing mFPA technology include FAME, GEST, Kepler, GAIA, LSST, and SNAP. The development of a mFPA mandates tighter control on the design trades, component development, CCD characterization, component integration, and performance verification testing. This paper addresses the capability Lockheed Martin Space Systems Company's (LMSSC) Advanced Technology Center (ATC) has developed to perform CCD characterization, mFPA assembly and alignment, and mFPA system level testing.

  2. Mosaic Focal Plane Development

    NASA Astrophysics Data System (ADS)

    Mason, D.; Horner, S.; Aamodt, E.

    Advances in manufacturing and applied sciences have enabled the development of large ground and spaced based astronomical instruments having a Field of View (FOV) large enough to capture a large portion of the universe in a single image. A large FOV can be accomplished using light weighted optics, improved structures, and the development of mosaic Focal Plane Assemblies (mFPAs). A mFPA comprises multiple Charged Coupled Devices (CCD) mounted onto a single baseplate integrated at the focus plane of the instrument. Examples of current, or proposed, missions utilizing mFPA technology include FAME, GEST, Kepler, GAIA, LSST, and SNAP. The development of a mFPA mandates tight control on the design trades of component development, CCD definition and characterization, component integration, and performance verification testing. This paper addresses the results of the Lockheed Martin Space Systems Company (LMSSC), Advanced Technology Center (ATC) developed mFPA. The design trades and performance characterization are services provided by the LMSSC ATC but not detailed in this paper.

  3. The Three Planes of Language.

    ERIC Educational Resources Information Center

    Sampson, Gloria

    1999-01-01

    Currently, the language sciences place together four different forms of mental activity on one plane of language, which results in confusion. This paper presents arguments from metaphysics, hermeneutics, and semiotics to demonstrate that there are actually three planes of language (a biologically-based information processing plane, a literal…

  4. Drilling cost-cutting

    SciTech Connect

    Capuano, L.E. Jr.

    1996-12-31

    This presentation by Louis E. Capuano, Jr., President, ThermaSource, Inc., discusses cost-cutting in the drilling phase of geothermal energy exploration and production. All aspects of a geothermal project including the drilling must be streamlined to make it viable and commercial. If production could be maximized from each well, there would be a reduction in drilling costs. This could be achieved in several ways, including big hole and multi-hole completion, directional drilling, better knowledge of the resource and where to penetrate, etc.

  5. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-07-31

    We have tested the loop elevation system. We raised the mast to approximately 25 to 30 degrees from horizontal. All went well. However, while lowering the mast, it moved laterally a couple of degrees. Upon visual inspection, severe spalling of the concrete on the face of the support pillar, and deformation of the steel support structure was observed. At this time, the facility is ready for testing in the horizontal position. A new air compressor has been received and set in place for the ACTS test loop. A new laboratory has been built near the ACTS test loop Roughened cups and rotors for the viscometer (RS300) were obtained. Rheologies of aqueous foams were measured using three different cup-rotor assemblies that have different surface roughness. The relationship between surface roughness and foam rheology was investigated. Re-calibration of nuclear densitometers has been finished. The re-calibration was also performed with 1% surfactant foam. A new cuttings injection system was installed at the bottom of the injection tower. It replaced the previous injection auger. A mechanistic model for cuttings transport with aerated mud has been developed. Cuttings transport mechanisms with aerated water at various conditions were experimentally investigated. A total of 39 tests were performed. Comparisons between the model predictions and experimental measurements show a satisfactory agreement. Results from the ultrasonic monitoring system indicated that we could distinguish between different sand levels. We also have devised ways to achieve consistency of performance by securing the sensors in the caps in exactly the same manner as long as the sensors are not removed from the caps. A preliminary test was conducted on the main flow loop at 100 gpm flow rate and 20 lb/min cuttings injection rate. The measured bed thickness using the ultrasonic method showed a satisfactory agreement with nuclear densitometer readings. Thirty different data points were collected after the test

  6. The cutting edge.

    PubMed

    Hagland, M; Lumsdon, K; Montague, J; Serb, C

    1995-08-01

    With managed care payment becoming the norm, employers actively pursuing keener benefits management, health care markets evolving at warp speed, and clinical and information technologies spawning new capabilities every day, the cutting edge in health care keeps slicing ever-deeper. With that in mind, we at Hospitals & Health Networks have developed a browser's compendium of some of the leading people, places (organizations and programs) and technologies that are helping move the field forward into the next stage. Each entry is unique; what they all share is an innovative quality that others will emulate. PMID:7627230

  7. Photochemical cutting of fabrics

    DOEpatents

    Piltch, Martin S.

    1994-01-01

    Apparatus for the cutting of garment patterns from one or more layers of fabric. A laser capable of producing laser light at an ultraviolet wavelength is utilized to shine light through a pattern, such as a holographic phase filter, and through a lens onto the one or more layers of fabric. The ultraviolet laser light causes rapid photochemical decomposition of the one or more layers of fabric, but only along the pattern. The balance of the fabric of the one or more layers of fabric is undamaged.

  8. Photochemical cutting of fabrics

    SciTech Connect

    Piltch, M.S.

    1994-11-22

    Apparatus is described for the cutting of garment patterns from one or more layers of fabric. A laser capable of producing laser light at an ultraviolet wavelength is utilized to shine light through a pattern, such as a holographic phase filter, and through a lens onto the one or more layers of fabric. The ultraviolet laser light causes rapid photochemical decomposition of the one or more layers of fabric, but only along the pattern. The balance of the fabric of the one or more layers of fabric is undamaged. 1 fig.

  9. Exemplar-based image inpainting using multiscale graph cuts.

    PubMed

    Liu, Yunqiang; Caselles, Vicent

    2013-05-01

    We present a novel formulation of exemplar-based inpainting as a global energy optimization problem, written in terms of the offset map. The proposed energy function combines a data attachment term that ensures the continuity of reconstruction at the boundary of the inpainting domain with a smoothness term that ensures a visually coherent reconstruction inside the hole. This formulation is adapted to obtain a global minimum using the graph cuts algorithm. To reduce the computational complexity, we propose an efficient multiscale graph cuts algorithm. To compensate the loss of information at low resolution levels, we use a feature representation computed at the original image resolution. This permits alleviation of the ambiguity induced by comparing only color information when the image is represented at low resolution levels. Our experiments show how well the proposed algorithm performs compared with other recent algorithms. PMID:22997270

  10. Structure analysis for plane geometry figures

    NASA Astrophysics Data System (ADS)

    Feng, Tianxiao; Lu, Xiaoqing; Liu, Lu; Li, Keqiang; Tang, Zhi

    2013-12-01

    As there are increasing numbers of digital documents for education purpose, we realize that there is not a retrieval application for mathematic plane geometry images. In this paper, we propose a method for retrieving plane geometry figures (PGFs), which often appear in geometry books and digital documents. First, detecting algorithms are applied to detect common basic geometry shapes from a PGF image. Based on all basic shapes, we analyze the structural relationships between two basic shapes and combine some of them to a compound shape to build the PGF descriptor. Afterwards, we apply matching function to retrieve candidate PGF images with ranking. The great contribution of the paper is that we propose a structure analysis method to better describe the spatial relationships in such image composed of many overlapped shapes. Experimental results demonstrate that our analysis method and shape descriptor can obtain good retrieval results with relatively high effectiveness and efficiency.

  11. NASA Connect: 'Plane Weather'

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Excerpt from the NASA Connect show 'Plane Weather' This clip explains how our weather occurs, and why Solar radiation is responsible. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.

  12. NASA Connect: 'Plane Weather'

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Excerpt from the NASA Connect show 'Plane Weather' This clip explains what high and low pressure weather systems are, and how they form. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.

  13. NASA Connect: 'Plane Weather'

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Excerpt from the NASA Connect show 'Plane Weather' This clip explains what high and low pressure weather systems are, and how these affect weather patterns. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.

  14. Vacuum plane waves: Cartan invariants and physical interpretation

    NASA Astrophysics Data System (ADS)

    Coley, A.; McNutt, D.; Milson, R.

    2012-12-01

    As an application of the Cartan invariants obtained using the Karlhede algorithm, we study a simple subclass of the PP-wave spacetimes, the gravitational plane waves. We provide an invariant classification of these spacetimes and then study a few notable subcases: the linearly polarized plane waves, the weak-field circularly polarized waves, and another class of plane waves found by imposing conditions on the set of invariants. As we study these spacetimes we relate the invariant structure (i.e., Cartan scalars) to the physical description of these spacetimes using the geodesic deviation equations relative to timelike geodesic observers.

  15. A Hexahedral Multigrid Approach for Simulating Cuts in Deformable Objects.

    PubMed

    Dick, C; Georgii, J; Westermann, R

    2011-11-01

    We present a hexahedral finite element method for simulating cuts in deformable bodies using the corotational formulation of strain at high computational efficiency. Key to our approach is a novel embedding of adaptive element refinements and topological changes of the simulation grid into a geometric multigrid solver. Starting with a coarse hexahedral simulation grid, this grid is adaptively refined at the surface of a cutting tool until a finest resolution level, and the cut is modeled by separating elements along the cell faces at this level. To represent the induced discontinuities on successive multigrid levels, the affected coarse grid cells are duplicated and the resulting connectivity components are distributed to either side of the cut. Drawing upon recent work on octree and multigrid schemes for the numerical solution of partial differential equations, we develop efficient algorithms for updating the systems of equations of the adaptive finite element discretization and the multigrid hierarchy. To construct a surface that accurately aligns with the cuts, we adapt the splitting cubes algorithm to the specific linked voxel representation of the simulation domain we use. The paper is completed by a convergence analysis of the finite element solver and a performance comparison to alternative numerical solution methods. These investigations show that our approach offers high computational efficiency and physical accuracy, and that it enables cutting of deformable bodies at very high resolutions. PMID:21173453

  16. Vibrator improves spark erosion cutting process

    NASA Technical Reports Server (NTRS)

    Thrall, L. R.

    1966-01-01

    Variable frequency mechanical vibrator improves spark erosion cutting process. The vibration of the cutting tip permits continual flushing away of residue around the cut area with nondestructive electric transformer oil during the cutting process.

  17. An algorithm for segmenting range imagery

    SciTech Connect

    Roberts, R.S.

    1997-03-01

    This report describes the technical accomplishments of the FY96 Cross Cutting and Advanced Technology (CC&AT) project at Los Alamos National Laboratory. The project focused on developing algorithms for segmenting range images. The image segmentation algorithm developed during the project is described here. In addition to segmenting range images, the algorithm can fuse multiple range images thereby providing true 3D scene models. The algorithm has been incorporated into the Rapid World Modelling System at Sandia National Laboratory.

  18. Simultaneous shaping of amplitude and phase of light in the entire output plane with a phase-only hologram

    PubMed Central

    Wu, Liang; Cheng, Shubo; Tao, Shaohua

    2015-01-01

    An iterative beam shaping algorithm is proposed to simultaneously shape the amplitude and phase of an optical beam. The proposed algorithm consists of one input plane and two completely overlapped output planes which refer to the output plane in real space. The two output planes are imposed with both amplitude and phase constraints, and the constrained areas in the two output planes are complementary. As a result, both the amplitude and phase in the entire output plane are controllable and arbitrary target complex amplitudes can be achieved with the proposed algorithm. The computing result of the proposed algorithm is a phase-only distribution which can be conveniently realized with a spatial light modulator or a fabricated diffractive optical element. Both simulations and experiments have verified the high performance of the proposed algorithm. PMID:26486183

  19. Vortex cutting in superconductors

    NASA Astrophysics Data System (ADS)

    Glatz, A.; Vlasko-Vlasov, V. K.; Kwok, W. K.; Crabtree, G. W.

    2016-08-01

    Vortex cutting and reconnection is an intriguing and still-unsolved problem central to many areas of classical and quantum physics, including hydrodynamics, astrophysics, and superconductivity. Here, we describe a comprehensive investigation of the crossing of magnetic vortices in superconductors using time dependent Ginsburg-Landau modeling. Within a macroscopic volume, we simulate initial magnetization of an anisotropic high temperature superconductor followed by subsequent remagnetization with perpendicular magnetic fields, creating the crossing of the initial and newly generated vortices. The time resolved evolution of vortex lines as they approach each other, contort, locally conjoin, and detach, elucidates the fine details of the vortex-crossing scenario under practical situations with many interacting vortices in the presence of weak pinning. Our simulations also reveal left-handed helical vortex instabilities that accompany the remagnetization process and participate in the vortex crossing events.

  20. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-01-31

    Final design of the mast was completed (Task 5). The mast is consisting of two welded plate girders, set next to each other, and spaced 14-inches apart. Fabrication of the boom will be completed in two parts solely for ease of transportation. The end pivot connection will be made through a single 2-inch diameter x 4 feet-8 inch long 316 SS bar. During installation, hard piping make-ups using Chiksan joints will connect the annular section and 4-inch return line to allow full movement of the mast from horizontal to vertical. Additionally, flexible hoses and piping will be installed to isolate both towers from piping loads and allow recycling operations respectively. Calibration of the prototype Foam Generator Cell has been completed and experiments are now being conducted. We were able to generate up to 95% quality foam. Work is currently underway to attach the Thermo-Haake RS300 viscometer and install a view port with a microscope to measure foam bubble size and bubble size distribution. Foam rheology tests (Task 13) were carried out to evaluate the rheological properties of the proposed foam formulation. After successful completion of the first foam test, two sets of rheological tests were conducted at different foam flow rates while keeping other parameters constant (100 psig, 70F, 80% quality). The results from these tests are generally in agreement with the previous foam tests done previously during Task 9. However, an unanticipated observation during these tests was that in both cases, the frictional pressure drop in 2 inch pipe was lower than that in the 3 inch and 4 inch pipes. We also conducted the first foam cuttings transport test during this quarter. Experiments on aerated fluids without cuttings have been completed in ACTF (Task 10). Gas and liquid were injected at different flow rates. Two different sets of experiments were carried out, where the only difference was the temperature. Another set of tests was performed, which covered a wide range of

  1. Making the cut

    PubMed Central

    Millard, Chris

    2013-01-01

    ‘Deliberate self-harm’, ‘self-mutilation’ and ‘self-injury’ are just some of the terms used to describe one of the most prominent issues in British mental health policy in recent years. This article demonstrates that contemporary literature on ‘self-harm’ produces this phenomenon (to varying extents) around two key characteristics. First, this behaviour is predominantly performed by those identified as female. Second, this behaviour primarily involves cutting the skin. These constitutive characteristics are traced back to a corpus of literature produced in the 1960s and 1970s in North American psychiatric inpatient institutions; analysis shows how pre-1960 works were substantially different. Finally, these gendered and behavioural assertions are shown to be the result of historically specific processes of exclusion and emphasis. PMID:23741086

  2. Study of high speed complex number algorithms. [for determining antenna for field radiation patterns

    NASA Technical Reports Server (NTRS)

    Heisler, R.

    1981-01-01

    A method of evaluating the radiation integral on the curved surface of a reflecting antenna is presented. A three dimensional Fourier transform approach is used to generate a two dimensional radiation cross-section along a planer cut at any angle phi through the far field pattern. Salient to the method is an algorithm for evaluating a subset of the total three dimensional discrete Fourier transform results. The subset elements are selectively evaluated to yield data along a geometric plane of constant. The algorithm is extremely efficient so that computation of the induced surface currents via the physical optics approximation dominates the computer time required to compute a radiation pattern. Application to paraboloid reflectors with off-focus feeds in presented, but the method is easily extended to offset antenna systems and reflectors of arbitrary shapes. Numerical results were computed for both gain and phase and are compared with other published work.

  3. An algorithm for solving the system-level problem in multilevel optimization

    NASA Technical Reports Server (NTRS)

    Balling, R. J.; Sobieszczanski-Sobieski, J.

    1994-01-01

    A multilevel optimization approach which is applicable to nonhierarchic coupled systems is presented. The approach includes a general treatment of design (or behavior) constraints and coupling constraints at the discipline level through the use of norms. Three different types of norms are examined: the max norm, the Kreisselmeier-Steinhauser (KS) norm, and the 1(sub p) norm. The max norm is recommended. The approach is demonstrated on a class of hub frame structures which simulate multidisciplinary systems. The max norm is shown to produce system-level constraint functions which are non-smooth. A cutting-plane algorithm is presented which adequately deals with the resulting corners in the constraint functions. The algorithm is tested on hub frames with increasing number of members (which simulate disciplines), and the results are summarized.

  4. Analysis of acoustic signals on welding and cutting

    SciTech Connect

    Morita, Takao; Ogawa, Yoji; Sumitomo, Takashi

    1995-12-31

    The sounds emitted during the welding and cutting processes are closely related to the processing phenomena, and sometimes they provide useful information for evaluation of their processing conditions. The analyses of acoustic signals from arc welding, plasma arc cutting, oxy-flame cutting, and water jet cutting are carried out in details in order to develop effective signal processing algorithm. The sound from TIG arc welding has the typical line spectrum which principal frequency, is almost the same as that of supplied electricity. The disturbance of welding process is clearly appeared oil the acoustic emission. The sound exposure level for CO{sub 2} or MIG welding is higher than that for TIG welding, and the relative intensity of the typical line spectrum caused by supplied electricity becomes low. But the sudden transition of welding condition oil produces an apparent change of sound exposure level. On the contrary, the acoustics from cutting processes are much louder than those of arc welding and show more chaotic behavior because the supplied fluid velocity and temperature of arc for cutting processes are much higher than those for welding processes. Therefore, it requires a special technique to extract the well meaning signals from the loud acoustic sounds. Further point of view, the reduction of acoustic exposure level becomes an important research theme with the growth of application fields of cutting processes.

  5. Investigation on cutting stability of jacket in decommissioning process

    NASA Astrophysics Data System (ADS)

    Li, Mei-qiu; Duan, Meng-lan; Huang, Yi

    2015-10-01

    Jacket cutting operation is one of the most complicated and highest risk operations in the process of decommissioning offshore piled platform, the security and stability of which must be assured. In this paper, the current research on offshore structure removal and jacket cutting is introduced, on the basis of which the types of load along with the load calculation method are determined. The main influences on the stability of a jacket in cutting are analyzed. The experiment test plan is drawn by using orthogonal testing method, and the formula of critical load during the cutting procedure is deduced by differential evolution algorithm. To verify the method and results of this paper, an offshore piled platform to be decommissioned in the South China Sea is taken for an example, and the detailed schedule for jacket cutting is made with the three-dimensional finite element model of the jacket established. The natural frequency, stress, strain and stability of the jacket during cutting process are calculated, which indicates that the results of finite element analysis agree well with that of the deduced formula. The result provides the scientific reference for guaranteeing the safety of jacket in cutting operation.

  6. Solution of the three-dimensional problem of plane wave diffraction by a two-period plane grating

    NASA Astrophysics Data System (ADS)

    Manenkov, S. A.

    2016-03-01

    Using the discrete source method, we develop an algorithm for solving the three-dimensional problem of wave scattering by a plane grating consisting of acoustically soft or acoustically stiff bodies. An efficient algorithm is proposed for determining the periodic Green's function of the grating. Numerical results are obtained for different geometries of the grating elements. The fulfillment of the energy conservation law is verified along with the fulfillment of the boundary condition at the surface of the central grating element.

  7. Prediction of dynamic cutting force and regenerative chatter stability in inserted cutters milling

    NASA Astrophysics Data System (ADS)

    Li, Zhongqun; Liu, Qiang; Yuan, Songmei; Huang, Kaisheng

    2013-05-01

    Currently, the modeling of cutting process mainly focuses on two aspects: one is the setup of the universal cutting force model that can be adapted to a broader cutting condition; the other is the setup of the exact cutting force model that can accurately reflect a true cutting process. However, there is little research on the prediction of chatter stablity in milling. Based on the generalized mathematical model of inserted cutters introduced by ENGIN, an improved geometrical, mechanical and dynamic model for the vast variety of inserted cutters widely used in engineering applications is presented, in which the average directional cutting force coefficients are obtained by means of a numerical approach, thus leading to an analytical determination of stability lobes diagram (SLD) on the axial depth of cut. A new kind of SLD on the radial depth of cut is also created to satisfy the special requirement of inserted cutter milling. The corresponding algorithms used for predicting cutting forces, vibrations, dimensional surface finish and stability lobes in inserted cutter milling under different cutting conditions are put forward. Thereafter, a dynamic simulation module of inserted cutter milling is implemented by using hybrid program of Matlab with Visual Basic. Verification tests are conducted on a vertical machine center for Aluminum alloy LC4 by using two different types of inserted cutters, and the effectiveness of the model and the algorithm is verified by the good agreement of simulation result with that of cutting tests under different cutting conditions. The proposed model can predict the cutting process accurately under a variety of cutting conditions, and a high efficient and chatter-free milling operation can be achieved by a cutting condition optimization in industry applications.

  8. Plastic tension of thin strip with symmetrical cut-outs

    NASA Astrophysics Data System (ADS)

    Nepershin, Rostislav I.

    2016-06-01

    Numerical solution of thin strip plane-stress tension with symmetrical cut-outs for Mises rigid-plastic solid is given. Limit plastic state of neck forming along the rigid-plastic boundaries induced by velocity discontinuity is considered. The problem solution can be useful for the material limit plastic formability estimation in the case of biaxial stress tension in complex thin sheet plastic forming technology.

  9. Plane Mercury librations

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2009-04-01

    theory of Mercury librations in longitude by using three characteristics of Mercury rotation determined in the paper [3]. Two from these parameters are values of angle of librations in longitude and angular velocity in moment of passage of perihelion of Mercury orbit on 17 April 2002: (^g)0 = 0007 ± 0001, (^?•? )0 = (2.10± 0.06)•? ars/d. Third parameter determined in [3] is a dynamical coefficient: K = (B -A)•(4Cm ) = (5.08± 0.30) × 10-5. B > A are principal moment of inertia, corresponding to equatorial axes of inertia; Cm is a polar moment of inertia of the mantle of Mercury. 1 Analytical theory of plane Mercury librations. This theory describes forced and free librations of Mercury in longitude in the frame of plane problem about resonant librations of Mercury considered or as non-spherical rigid body, or as system of rigid non-spherical mantle and liquid ellipsoidal core. Saving the main terms for the perturbations of angle of librations ^g and angular velocity ^? in both mentioned cases we will have formulae [6]: ^g = K(E sin M + E sin2M + E sin 3M + E sin4M + E sin5M ) 1 2 3 4 5+K0 sin(E šKM- - φ) (A)

  10. Spine image fusion via graph cuts.

    PubMed

    Miles, Brandon; Ben Ayed, Ismail; Law, Max W K; Garvin, Greg; Fenster, Aaron; Li, Shuo

    2013-07-01

    This study investigates a novel CT/MR spine image fusion algorithm based on graph cuts. This algorithm allows physicians to visually assess corresponding soft tissue and bony detail on a single image eliminating mental alignment and correlation needed when both CT and MR images are required for diagnosis. We state the problem as a discrete multilabel optimization of an energy functional that balances the contributions of three competing terms: (1) a squared error, which encourages the solution to be similar to the MR input, with a preference to strong MR edges; (2) a squared error, which encourages the solution to be similar to the CT input, with a preference to strong CT edges; and (3) a prior, which favors smooth solutions by encouraging neighboring pixels to have similar fused-image values. We further introduce a transparency-labeling formulation, which significantly reduces the computational load. The proposed graph-cut fusion guarantees nearly global solutions, while avoiding the pix elation artifacts that affect standard wavelet-based methods. We report several quantitative evaluations/comparisons over 40 pairs of CT/MR images acquired from 20 patients, which demonstrate a very competitive performance in comparisons to the existing methods. We further discuss various case studies, and give a representative sample of the results. PMID:23372071

  11. Plane symmetric thin-shell wormholes: Solutions and stability

    SciTech Connect

    Lemos, Jose P. S.; Lobo, Francisco S. N.

    2008-08-15

    Using the cut-and-paste procedure, we construct static and dynamic, plane symmetric wormholes by surgically grafting together two spacetimes of plane symmetric vacuum solutions with a negative cosmological constant. These plane symmetric wormholes can be interpreted as domain walls connecting different universes, having planar topology, and upon compactification of one or two coordinates, cylindrical topology or toroidal topology, respectively. A stability analysis is carried out for the dynamic case by taking into account specific equations of state, and a linearized stability analysis around static solutions is also explored. It is found that thin-shell wormholes made of a dark energy fluid or of a cosmological constant fluid are stable, while thin-shell wormholes made of phantom energy are unstable.

  12. Optimum cutting parameters selection strategy based on neural network and artificial intelligence

    NASA Astrophysics Data System (ADS)

    Liang, Jian C.; Wen, Xisen; Li, Shengyi; Yang, Shuzi

    1995-08-01

    In this paper an optimum cutting parameters selection strategy based on neural network and artificial intelligence is proposed. It combines NN with AI and solves the problems of intelligent decision-making for cutting parameters during machining process. BP algorithm and inference engine design are discussed. Application examples of the strategy are simulated. The results show that the proposed strategy is very effective.

  13. Object tracking based on bit-planes

    NASA Astrophysics Data System (ADS)

    Li, Na; Zhao, Xiangmo; Liu, Ying; Li, Daxiang; Wu, Shiqian; Zhao, Feng

    2016-01-01

    Visual object tracking is one of the most important components in computer vision. The main challenge for robust tracking is to handle illumination change, appearance modification, occlusion, motion blur, and pose variation. But in surveillance videos, factors such as low resolution, high levels of noise, and uneven illumination further increase the difficulty of tracking. To tackle this problem, an object tracking algorithm based on bit-planes is proposed. First, intensity and local binary pattern features represented by bit-planes are used to build two appearance models, respectively. Second, in the neighborhood of the estimated object location, a region that is most similar to the models is detected as the tracked object in the current frame. In the last step, the appearance models are updated with new tracking results in order to deal with environmental and object changes. Experimental results on several challenging video sequences demonstrate the superior performance of our tracker compared with six state-of-the-art tracking algorithms. Additionally, our tracker is more robust to low resolution, uneven illumination, and noisy video sequences.

  14. Automatic location of microscopic focal planes for computerized stereology

    NASA Astrophysics Data System (ADS)

    Elozory, Daniel T.; Bonam, Om Pavithra; Kramer, Kurt; Goldgof, Dmitry B.; Hall, Lawrence O.; Mangual, Osvaldo; Mouton, Peter R.

    2011-03-01

    When applying design-based stereology to biological tissue, there are two primary applications for an auto-focusing function in the software of computerized stereology system. The system must first locate the in-focus optical planes at the upper and lower surfaces of stained tissue sections, thus identifying the top and bottom as well as the thickness of the tissue. Second, the system must find the start and end along the Z-axis of stained objects within a Z-stack of images through tissue sections. In contrast to traditional autofocus algorithms that seek a global maximum or peak on the focus curve, the goal of this study was to find the two "knees" of the focus curve that represent the "just out-of-focus" focal planes. The upper surface of the tissue section is defined as the image just before focus is detected moving down the Z-stack. Continuing down, the lower surface is defined as the first image of the last set of adjacent images where focus is no longer detected. The performance of seven focus algorithms in locating the top and bottom focal planes of tissue sections was analyzed by comparing each algorithm on 34 Z-stacks including a total of 828 images. The Thresholded Absolute Gradient algorithm outperformed all others, correctly identifying the top or bottom focal plane within an average of 1 μm on the training data as well as the test data.

  15. NCC-RANSAC: A Fast Plane Extraction Method for 3-D Range Data Segmentation

    PubMed Central

    Qian, Xiangfei; Ye, Cang

    2015-01-01

    This paper presents a new plane extraction (PE) method based on the random sample consensus (RANSAC) approach. The generic RANSAC-based PE algorithm may over-extract a plane, and it may fail in case of a multistep scene where the RANSAC procedure results in multiple inlier patches that form a slant plane straddling the steps. The CC-RANSAC PE algorithm successfully overcomes the latter limitation if the inlier patches are separate. However, it fails if the inlier patches are connected. A typical scenario is a stairway with a stair wall where the RANSAC plane-fitting procedure results in inliers patches in the tread, riser, and stair wall planes. They connect together and form a plane. The proposed method, called normal-coherence CC-RANSAC (NCC-RANSAC), performs a normal coherence check to all data points of the inlier patches and removes the data points whose normal directions are contradictory to that of the fitted plane. This process results in separate inlier patches, each of which is treated as a candidate plane. A recursive plane clustering process is then executed to grow each of the candidate planes until all planes are extracted in their entireties. The RANSAC plane-fitting and the recursive plane clustering processes are repeated until no more planes are found. A probabilistic model is introduced to predict the success probability of the NCC-RANSAC algorithm and validated with real data of a 3-D time-of-flight camera–SwissRanger SR4000. Experimental results demonstrate that the proposed method extracts more accurate planes with less computational time than the existing RANSAC-based methods. PMID:24771605

  16. Research on optimal path planning algorithm of task-oriented optical remote sensing satellites

    NASA Astrophysics Data System (ADS)

    Liu, Yunhe; Xu, Shengli; Liu, Fengjing; Yuan, Jingpeng

    2015-08-01

    GEO task-oriented optical remote sensing satellite, is very suitable for long-term continuous monitoring and quick access to imaging. With the development of high resolution optical payload technology and satellite attitude control technology, GEO optical remote sensing satellites will become an important developing trend for aerospace remote sensing satellite in the near future. In the paper, we focused on GEO optical remote sensing satellite plane array stare imaging characteristics and real-time leading mission of earth observation mode, targeted on satisfying needs of the user with the minimum cost of maneuver, and put forward the optimal path planning algorithm centered on transformation from geographic coordinate space to Field of plane, and finally reduced the burden of the control system. In this algorithm, bounded irregular closed area on the ground would be transformed based on coordinate transformation relations in to the reference plane for field of the satellite payload, and then using the branch and bound method to search for feasible solutions, cutting off the non-feasible solution in the solution space based on pruning strategy; and finally trimming some suboptimal feasible solutions based on the optimization index until a feasible solution for the global optimum. Simulation and visualization presentation software testing results verified the feasibility and effectiveness of the strategy.

  17. Energy expenditure cutting supercane.

    PubMed

    Spurr, G B; Barac-nieto, M; Maksud, M G

    1975-12-01

    VO2 VE, and heart rates (fH) were measured in 61 Colombian sugarcane cutters while harvesting cane in the AM and PM and in the laboratory during a VO2max test. Productivity and sweat rates were also measured in the field. The subjects had an estimated dietary intake of 2,970 kcal/day, which was lower than calculated daily energy expenditure. During the work measurements the VO2 was 1.5 1/min, VE 48 1/min, and fH 135 beats/min; there were no differences between AM and PM values. The subjects sustained about 35% of VO2max during the 8 h workday, but worked at 57% of VO2max during the tests. Measured energy cost was 7.4 +/- 1.5 kcal/min during the workday. Sweat rates were higher PM than AM (5 KG/8 h day). Grouping of the men according to productivity demonstrated that taller, heavier men were better producers and had lower calculated heart rates at VO2 1.51/min. Efficiency of cane cutting was higher (9%) PM. PMID:1240097

  18. Corner-cutting mining assembly

    DOEpatents

    Bradley, John A.

    1983-01-01

    A mining assembly includes a primary rotary cutter mounted on one end of a support shaft and four secondary rotary cutters carried on the same support shaft and positioned behind the primary cutters for cutting corners in the hole cut by the latter.

  19. Cutting and Self-Harm

    MedlinePlus

    ... sad Cutting and self-harm Cutting and self-harm Self-harm, sometimes called self-injury, is when a person ... about how one girl helps herself not self-harm. What are signs of self-injury in others? ...

  20. Cutting Head for Ultrasonic Lithotripsy

    NASA Technical Reports Server (NTRS)

    Angulo, Earl D. (Inventor); Goodfriend, Roger (Inventor)

    1989-01-01

    A cutting head for attachment to the end of the wire probe of an ultrasonic kidney stone disintegration instrument. The cutting head has a plurality of circumferentially arranged teeth formed at one end thereof to provide a cup-shaped receptacle for kidney stones encountered during the disintegration procedure. An integral reduced diameter collar diminishes stress points in the wire and reduces breakage thereof.

  1. Tubing and cable cutting tool

    NASA Technical Reports Server (NTRS)

    Mcsmith, D. D.; Richardson, J. I. (Inventor)

    1984-01-01

    A hand held hydraulic cutting tool was developed which is particularly useful in deactivating ejection seats in military aircraft rescue operations. The tool consists primarily of a hydraulic system composed of a fluid reservoir, a pumping piston, and an actuator piston. Mechanical cutting jaws are attached to the actuator piston rod. The hydraulic system is controlled by a pump handle. As the pump handle is operated the actuator piston rod is forced outward and thus the cutting jaws are forced together. The frame of the device is a flexible metal tubing which permits easy positioning of the tool cutting jaws in remote and normally inaccessible locations. Bifurcated cutting edges ensure removal of a section of the tubing or cable to thereby reduce the possibility of accidental reactivation of the tubing or cable being severed.

  2. A Distance-Weighted Graph-Cut Method for the Segmentation of Laser Point Clouds

    NASA Astrophysics Data System (ADS)

    Dutta, A.; Engels, J.; Hahn, M.

    2014-08-01

    Normalized Cut according to (Shi and Malik 2000) is a well-established divisive image segmentation method. Here we use Normalized Cut for the segmentation of laser point clouds in urban areas. In particular we propose an edge weight measure which takes local plane parameters, RGB values and eigenvalues of the covariance matrices of the local point distribution into account. Due to its target function, Normalized Cut favours cuts with "small cut lines/surfaces", which appears to be a drawback for our application. We therefore modify the target function, weighting the similarity measures with distant-depending weights. We call the induced minimization problem "Distance-weighted Cut" (DWCut). The new target function leads to a slightly more complicated generalized eigenvalue problem than in case of the Normalized Cut; on the other hand, the new target function is easier to interpret and avoids the just-mentioned drawback. DWCut can be beneficially combined with an aggregation in order to reduce the computational effort and to avoid shortcomings due to insufficient plane parameters. Finally we present examples for the successful application of the Distance-weighted Cut principle. The method was implemented as a plugin into the free and open source geographic information system SAGA; for preprocessing steps the proprietary SAGA-based LiDAR software LIS was applied.

  3. Joint and segmental mechanics differ between cutting maneuvers in skilled athletes.

    PubMed

    Havens, Kathryn L; Sigward, Susan M

    2015-01-01

    Cutting is necessary for participation in multidirectional sports but is also associated with non-contact ACL injury. Whole body demands of deceleration and redirection increase with greater cut angles. However, it is not known how these demands relate to differences in joint and segmental mechanics. Understanding the relationship between whole body and joint mechanics necessary for cutting and those related to risk for injury is important for the development of injury prevention training programs. The purpose of this study is to determine how joint and segmental mechanics change to meet increasing deceleration and redirection demands during cutting. Lower limb and trunk kinematics and kinetics were evaluated during the execution of two sidestep cutting maneuvers (to 45 and 90 degrees) in twenty-five healthy soccer players. A two-way multivariate analysis of covariance (MANCOVA) determined that differences existed between task directions but not sexes when considering all dependent variables and covarying for approach velocity (α≤0.05). Post hoc analyses revealed that the larger deceleration and redirection demands of the 90-degree cut did not translate into larger angles, moments and power across all lower extremity joints. In the sagittal plane, the knee appeared to primarily accommodate the greater deceleration demands of the sharper cut. These data further suggest that the hip may play a different role during cutting to smaller and larger angles and also illustrate a pattern of engagement in the sagittal and frontal planes that has not been described previously. PMID:25194689

  4. Modeling of metal cutting as purposeful fracture of work material

    NASA Astrophysics Data System (ADS)

    Abushawashi, Yalla Mussa

    Metal cutting, or simply machining, is one of the oldest processes for shaping components in the manufacturing industry. It is widely quoted that 15% of the value of all mechanical components manufactured worldwide is derived from machining operations. The most influential model for metal cutting is the single-shear plane model (SSPM) of chip formation. The common notion is that new surfaces are formed simply by `plastic flow around the tool tip' so that metal cutting is one of the deforming processes. A number of cutting theories and the finite element method (FEM) models have been developed based on this concept. Metal cutting simulation models are available in commercial FEM packages. However, these model predictions and numerical simulations do not agree with the trends and phenomena observed in metal cutting experiments. Therefore, it is of the utmost importance to have a physically sound model of metal cutting. This thesis is based on the concept that metal cutting is the purposeful fracture of the work material. To reduce the energy required for fracture, one should minimize the energy of plastic deformation of the work material in its transformation into the chip because this energy constitutes up to 80% of the total energy required by the cutting system. Increased tool life and machining efficiency are the outcomes of such an optimization. To investigate this concept requires a work material model which considers the entire process from plastic deformation, damage initiation to final fracture. In this thesis, a work material model was developed based on the recent advancement in ductile fracture of metals. The model parameters must be determined under conditions that are pertinent to metal cutting. In machining, the work material experiences a complex, evolving multi-axial stress history. The existing testing specimens such as the notched bars and flat grooved specimens do not cover the stress triaxiality range found in machining. To generate material

  5. Cutting Head for Ultrasonic Lithotripsy

    NASA Technical Reports Server (NTRS)

    Angulo, E. D.; Goodfriend, R.

    1987-01-01

    Kidney stones lodged in urinary tract disintegrated with increased safety and efficiency by cutting head attached to end of vibrated wire probe. Aligns probe with stone and enables probe to vibrate long enough to disintegrate stone. Design of cutting head reduces risk of metal-fatigue-induced breakage of probe tip leaving metal fragments in urinary tract. Teeth of cutting head both seat and fragment kidney stone, while extension of collar into catheter lessens mechanical strain in probe wire, increasing probe life and lessening danger of in situ probe breakage.

  6. Genetic algorithms

    NASA Technical Reports Server (NTRS)

    Wang, Lui; Bayer, Steven E.

    1991-01-01

    Genetic algorithms are mathematical, highly parallel, adaptive search procedures (i.e., problem solving methods) based loosely on the processes of natural genetics and Darwinian survival of the fittest. Basic genetic algorithms concepts are introduced, genetic algorithm applications are introduced, and results are presented from a project to develop a software tool that will enable the widespread use of genetic algorithm technology.

  7. Oblique sectional planes of block plastinates eased by Sac Plastination.

    PubMed

    Kürtül, Ibrahim; Hammer, Niels; Rabi, Suganthy; Saito, Toshiyuki; Böhme, Jörg; Steinke, Hanno

    2012-07-01

    To find an oblique cutting plane of a plastinate, e.g. to cut gamma-nails in the femur, the Block Plastination technique was modified. After CT and MRI examination, the specimens were plastinated with the standard resin mixture E6/E12/E600. Instead of using a box to form a block during the casting and curing stage, we embedded the specimen in a sac made of polyester foil. A polymerized wooden block was attached to the specimen. The sac was wrapped with tape to the embedded specimen with the block. This approach limited the amount of required resin to the inner volume of the plastinate. Then, the plastination sac was put in the incubator for further polymerization and curing. When the foil was removed from the plastinated specimen, the wooden block served as a socket for the grip when sawing. The outer shape of the specimen remained visible. Doing so, the adequate cutting plane could be determined easily. PMID:22209028

  8. Cutting thin sections of bone

    NASA Technical Reports Server (NTRS)

    Ashley, W. W.

    1972-01-01

    Medical equipment for obtaining repetitive planoparallel sections of bone to study healing of bone structure under high gravity stress is described. Device consists of modified saw with diamond cutting edges. Construction of device and manner of use are explained.

  9. Laser cutting of energetic materials

    SciTech Connect

    Rivera, T.; Muenchausen, R.; Sanchez, J.

    1998-12-01

    The authors have demonstrated the feasibility of safely and efficiently cutting and drilling metal cases containing a variety of high explosives (HE) using a Nd:YAG laser. Spectral analysis of the optical emission, occurring during the laser-induced ablation process, is used to identify the removed material. By monitoring changes in the optical emission during the cutting process, the metal-He interface can be observed in real time and the cutting parameters adjusted accordingly. For cutting the HE material itself, the authors have demonstrated that this can be safely and efficiently accomplished by means of a ultraviolet (UV) laser beam obtained from the same Nd:YAG laser using the third or fourth harmonics. They are currently applying this technology to UXO identification and ordnance demilitarization.

  10. Refrigerated cutting tools improve machining of superalloys

    NASA Technical Reports Server (NTRS)

    Dudley, G. M.

    1971-01-01

    Freon-12 applied to tool cutting edge evaporates quickly, leaves no residue, and permits higher cutting rate than with conventional coolants. This technique increases cutting rate on Rene-41 threefold and improves finish of machined surface.

  11. A general algorithm for the construction of contour plots

    NASA Technical Reports Server (NTRS)

    Johnson, W.; Silva, F.

    1981-01-01

    An algorithm is described that performs the task of drawing equal level contours on a plane, which requires interpolation in two dimensions based on data prescribed at points distributed irregularly over the plane. The approach is described in detail. The computer program that implements the algorithm is documented and listed.

  12. Parallax handling of image stitching using dominant-plane homography

    NASA Astrophysics Data System (ADS)

    Pang, Zhaofeng; Li, Cheng; Zhao, Baojun; Tang, Linbo

    2015-10-01

    In this paper, we present a novel image stitching method to handle parallax in practical application. For images with significant amount of parallax, the more effective approach is to align roughly and globally the overlapping regions and then apply a seam-cutting method to composite naturally stitched images. It is well known that images can be modeled by various planes result from the projective parallax under non-ideal imaging condition. The dominant-plane homography has important advantages of warping an image globally and avoiding some local distortions. The proposed method primarily addresses large parallax problem through two steps: (1) selecting matching point pairs located on the dominant plane, by clustering matching correspondences and then measuring the cost of each cluster; and (2) in order to obtain a plausible seam, edge maps of overlapped area incorporation arithmetic is adopted to modify the standard seam-cutting method. Furthermore, our approach is demonstrated to achieve reliable performance of handling parallax through a mass of experimental comparisons with state-of-the-art methods.

  13. Interactive cutting path analysis programs

    NASA Technical Reports Server (NTRS)

    Weiner, J. M.; Williams, D. S.; Colley, S. R.

    1975-01-01

    The operation of numerically controlled machine tools is interactively simulated. Four programs were developed to graphically display the cutting paths for a Monarch lathe, Cintimatic mill, Strippit sheet metal punch, and the wiring path for a Standard wire wrap machine. These programs are run on a IMLAC PDS-ID graphic display system under the DOS-3 disk operating system. The cutting path analysis programs accept input via both paper tape and disk file.

  14. Cutting head for ultrasonic lithotripsy

    NASA Technical Reports Server (NTRS)

    Anguluo, E. D.; Goodfriend, R. (Inventor)

    1985-01-01

    A cutting head for attachment to the end of the wire probe of an ultrasonic kidney stone disintegration instrument is described. The cutting head has a plurality of circumferentially arranged teeth formed at one end thereof to provide a cup shaped receptacle for kidney stones encountered during the disintegration procedure. An integral reduced diameter collar diminishes stress points in the wire and reduce breakage thereof.

  15. Economic technology of laser cutting

    NASA Astrophysics Data System (ADS)

    Fedin, Alexander V.; Shilov, Igor V.; Vassiliev, Vladimir V.; Malov, Dmitri V.; Peskov, Vladimir N.

    2000-02-01

    The laser cutting of color metals and alloys by a thickness more than 2 mm has significant difficulties due to high reflective ability and large thermal conduction. We made it possible to raise energy efficiency and quality of laser cutting by using a laser processing system (LPS) consisting both of the YAG:Nd laser with passive Q-switching on base of LiF:F2- crystals and the CO2 laser. A distinctive feature of the LPS is that the radiation of different lasers incorporated in a coaxial beam has simultaneously high level of peak power (more than 400 kW in a TEM00 mode) and significant level of average power (up to 800 W in a TEM01 mode of the CO2 laser). The application of combined radiation for cutting of an aluminum alloy of D16 type made it possible to decrease the cutting energy threshold in 1.7 times, to increase depth of treatment from 2 up to 4 mm, and velocity from 0.015 up to 0.7 m/min, and also to eliminate application of absorptive coatings. At cutting of steels the velocity of treatment was doubled, and also an oxygen flow was eliminated from the technological process and replaced by the air. The obtained raise of energy efficiency and quality of cutting is explained by an essential size reducing of a formed penetration channel and by the shifting of a thermal cutting mode from melting to evaporation. The evaluation of interaction efficiency of a combined radiation was produced on the basis of non-stationary thermal-hydrodynamic model of a heating source moving as in the cutting direction, and also into the depth of material.

  16. Underwater welding, cutting and inspection

    SciTech Connect

    Tsai, C.L. . Ohio Underwater Welding Center)

    1995-02-01

    Underwater welding, cutting and inspection of offshore, inland waterway and port facilities are becoming a requirement for both military and industrial communities, as maintenance and repair costs continue to escalate, and as many of the facilities are in operation well beyond their intended design life. In nuclear applications, underwater welding, cutting and inspection for repair and modification of irradiated nuclear power plant components are also a requirement. This article summarizes recent developments in this emerging underwater technology.

  17. EPA rule could cut pollutants

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The U.S. Environmental Protection Agency issued a rule on November 14 that it claims could nearly eliminate dioxin discharges into waterways and reduce other toxic pollutants into the air and water from 155 pulp and paper mills.EPA estimates that results will include a 96% reduction in dioxin and a nearly 60% reduction in toxic air pollutants. Also, volatile organic compounds and sulfur emissions could be cut in half, with particulate matter cut by 37%.

  18. Microwave assisted hard rock cutting

    DOEpatents

    Lindroth, David P.; Morrell, Roger J.; Blair, James R.

    1991-01-01

    An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

  19. Prediction of Cutting Forces Using ANNs Approach in Hard Turning of AISI 52100 steel

    SciTech Connect

    Makhfi, Souad; Habak, Malek; Velasco, Raphael; Haddouche, Kamel; Vantomme, Pascal

    2011-05-04

    In this study, artificial neural networks (ANNs) was used to predict cutting forces in the case of machining the hard turning of AISI 52100 bearing steel using cBN cutting tool. Cutting forces evolution is considered as the key factors which affect machining. Predicting cutting forces evolution allows optimizing machining by an adaptation of cutting conditions. In this context, it seems interesting to study the contribution that could have artificial neural networks (ANNs) on the machining forces prediction in both numerical and experiment studies. Feed-forward multi-layer neural networks trained by the error back-propagation (BP) algorithm are used. Levenberg-Marquardt (LM) optimization algorithm was used for finding out weights. The training of the network is carried out with experimental machining data.The input dataset used are cutting speed, feed rate, cutting depth and hardness of the material. The output dataset used are cutting forces (Ft-cutting force, Fa- feed force and Fr- radial force).Results of the neural networks approach, in comparison with experimental data are discussed in last part of this paper.

  20. A knowledge-based adaptive control environment for an industrial laser cutting system

    NASA Astrophysics Data System (ADS)

    Huang, M. Y.; Chatwin, C. R.

    A hierarchically structured environment that integrates a knowledge- based expert system, adaptive process control and pattern recognition techniques for controlling a laser cutting process is described. Knowledge of the laser cutting process for different materials is organised and encoded into a rule-based system. An adaptive control algorithm based on on-line recursive parameter estimation and on-line control law synthesis was adopted for the highly non-linear cutting process control. Cutting speed was selected as the major control variable. Irradiance emitted from the cut front is used for the feedback signal to this adaptive controller. The irradiance signal feeds the recursive parameter estimator for system identification. Techniques of pattern recognition, which have been well developed in coherent optics, were applied to assess cut quality by characterising the exit spark cone images of the gas assisted laser cutting process. Images from the cutting processes were grabbed, edge enhanced and correlated with a synthetic discriminant function filter which was synthesised from reference images to give good cut quality. Results from digital simulations based on these pattern recognition algorithms are also presented.

  1. Apparatus for washing drill cuttings

    SciTech Connect

    Lott, W. G.

    1985-10-15

    An apparatus for cleansing a stream of drilling fluid fouled drill cuttings having a housing divided into a plurality of compartments each designed to retain cleansing fluid. A spinning force is imparted into the incoming fouled drill cuttings in an inlet chamber wherein cleansing fluid is intimately mixed with the fouled drill cuttings. A decanting chamber removes liberated drilling fluid from the cuttings and disposes of such drilling fluid from the apparatus via a drain trough assembly. The underflow from the decanter is passed through a solids concentrating assembly wherein the coarse solids are deposited in a concentrating assembly bottoms chamber wherein the settled drill cuttings are removed from the apparatus. The overhead stream from the solids concentrating assembly is driected to a second decanter for removal of any remaining drilling fluid and fine drill cuttings entrained therein from the apparatus via the drain trough assembly. The remaining fluid in the concentrating assembly bottoms chamber is recirculated to the second decanting chamber and the inlet chamber.

  2. Three Dimensional Sheaf of Ultrasound Planes Reconstruction (SOUPR) of Ablated Volumes

    PubMed Central

    Ingle, Atul; Varghese, Tomy

    2014-01-01

    This paper presents an algorithm for three dimensional reconstruction of tumor ablations using ultrasound shear wave imaging with electrode vibration elastography. Radiofrequency ultrasound data frames are acquired over imaging planes that form a subset of a sheaf of planes sharing a common axis of intersection. Shear wave velocity is estimated separately on each imaging plane using a piecewise linear function fitting technique with a fast optimization routine. An interpolation algorithm then computes velocity maps on a fine grid over a set of C-planes that are perpendicular to the axis of the sheaf. A full three dimensional rendering of the ablation can then be created from this stack of C-planes; hence the name “Sheaf Of Ultrasound Planes Reconstruction” or SOUPR. The algorithm is evaluated through numerical simulations and also using data acquired from a tissue mimicking phantom. Reconstruction quality is gauged using contrast and contrast-to-noise ratio measurements and changes in quality from using increasing number of planes in the sheaf are quantified. The highest contrast of 5 dB is seen between the stiffest and softest regions of the phantom. Under certain idealizing assumptions on the true shape of the ablation, good reconstruction quality while maintaining fast processing rate can be obtained with as few as 6 imaging planes suggesting that the method is suited for parsimonious data acquisitions with very few sparsely chosen imaging planes. PMID:24808405

  3. The solar system's invariable plane

    NASA Astrophysics Data System (ADS)

    Souami, D.; Souchay, J.

    2012-07-01

    Context. The dynamics of solar system objects, such as dwarf planets and asteroids, has become a well-established field of celestial mechanics in the past thirty years, owing to the improvements that have been made in observational techniques and numerical studies. In general, the ecliptic is taken as the reference plane in these studies, although there is no dynamical reason for doing so. In contrast, the invariable plane as originally defined by Laplace, seems to be a far more natural choice. In this context, the latest study of this plane dates back to Burkhardt. Aims: We define and determine the orientation of the invariable plane of the solar system with respect to both the ICRF and the equinox-ecliptic of J2000.0, and evaluate the accuracy of our determination. Methods: Using the long-term numerical ephemerides DE405, DE406, and INPOP10a over their entire available time span, we computed the total angular momentum of the solar system, as well as the individual contribution to it made by each of the planets, the dwarf planets Pluto and Ceres, and the two asteroids Pallas and Vesta. We then deduced the orientation of the invariable plane from these ephemerides. Results: We update the previous results on the determination of the orientation of the invariable plane with more accurate data, and a more complete analysis of the problem, taking into account the effect of the dwarf planet (1) Ceres as well as two of the biggest asteroids, (4) Vesta and (2) Pallas. We show that the inclusion of these last three bodies significantly improves the accuracy of determination of the invariable plane, whose orientation over a 100 y interval does not vary more than 0.1 mas in inclination, and 0.3 mas in longitude of the ascending node. Moreover, we determine the individual contributions of each body to the total angular momentum of the solar system, as well as the inclination and longitude of the node with respect to this latter plane. Conclusions: Owing to the high accuracy

  4. Effects of Two Football Stud Types on Knee and Ankle Kinetics of Single-Leg Land-Cut and 180° Cut Movements on Infilled Synthetic Turf.

    PubMed

    Bennett, Hunter J; Brock, Elizabeth; Brosnan, James T; Sorochan, John C; Zhang, Songning

    2015-10-01

    Higher ACL injury rates have been recorded in cleats with higher torsional resistance in American football, which warrants better understanding of shoe/stud-dependent joint kinetics. The purpose of this study was to determine differences in knee and ankle kinetics during single-leg land cuts and 180° cuts on synthetic infilled turf while wearing 3 types of shoes. Fourteen recreational football players performed single-leg land cuts and 180° cuts in nonstudded running shoes (RS) and in football shoes with natural (NTS) and synthetic turf studs (STS). Knee and ankle kinetic variables were analyzed with a 3 × 2 (shoe × movement) repeated-measures ANOVA (P < .05). A significant shoe-by-movement interaction was found in loading response peak knee adduction moments, with NTS producing smaller moments compared with both STS and RS only in 180° cuts. Reduced peak negative plantar flexor powers were also found in NTS compared with STS. The single-leg land cut produced greater loading response and push-off peak knee extensor moments, as well as peak negative and positive extensor and plantar flexor powers, but smaller loading peak knee adduction moments and push-off peak ankle eversion moments than 180° cuts. Overall, the STS and 180° cuts resulted in greater frontal plane knee loading and should be monitored for possible increased ACL injury risks. PMID:25950515

  5. Coincidence lattices in the hyperbolic plane.

    PubMed

    Rodríguez-Andrade, M A; Aragón-González, G; Aragón, J L; Gómez-Rodríguez, A

    2011-01-01

    The problem of coincidences of lattices in the space R(p,q), with p + q = 2, is analyzed using Clifford algebra. We show that, as in R(n), any coincidence isometry can be decomposed as a product of at most two reflections by vectors of the lattice. Bases and coincidence indices are constructed explicitly for several interesting lattices. Our procedure is metric-independent and, in particular, the hyperbolic plane is obtained when p = q = 1. Additionally, we provide a proof of the Cartan-Dieudonné theorem for R(p,q), with p + q = 2, that includes an algorithm to decompose an orthogonal transformation into a product of reflections. PMID:21173471

  6. Wafer plane inspection with soft resist thresholding

    NASA Astrophysics Data System (ADS)

    Hess, Carl; Shi, Rui-fang; Wihl, Mark; Xiong, Yalin; Pang, Song

    2008-10-01

    Wafer Plane Inspection (WPI) is an inspection mode on the KLA-Tencor TeraScaTM platform that uses the high signalto- noise ratio images from the high numerical aperture microscope, and then models the entire lithographic process to enable defect detection on the wafer plane[1]. This technology meets the needs of some advanced mask manufacturers to identify the lithographically-significant defects while ignoring the other non-lithographically-significant defects. WPI accomplishes this goal by performing defect detection based on a modeled image of how the mask features would actually print in the photoresist. There are several advantages to this approach: (1) the high fidelity of the images provide a sensitivity advantage over competing approaches; (2) the ability to perform defect detection on the wafer plane allows one to only see those defects that have a printing impact on the wafer; (3) the use of modeling on the lithographic portion of the flow enables unprecedented flexibility to support arbitrary illumination profiles, process-window inspection in unit time, and combination modes to find both printing and non-printing defects. WPI is proving to be a valuable addition to the KLA-Tencor detection algorithm suite. The modeling portion of WPI uses a single resist threshold as the final step in the processing. This has been shown to be adequate on several advanced customer layers, but is not ideal for all layers. Actual resist chemistry has complicated processes including acid and base-diffusion and quench that are not consistently well-modeled with a single resist threshold. We have considered the use of an advanced resist model for WPI, but rejected it because the burdensome requirements for the calibration of the model were not practical for reticle inspection. This paper describes an alternative approach that allows for a "soft" resist threshold to be applied that provides a more robust solution for the most challenging processes. This approach is just

  7. Cutting inlays with a laser

    NASA Astrophysics Data System (ADS)

    Swaczyna, Irena; Grabczewski, Zbigniew

    1995-03-01

    To cut inlay from a stack of glued veneer a CO2 HEBAR-1A laser was used. For setting optimal working parameters of the set used in industrial production of inlay the following elements were defined: the shape and dimensions of the cutting fissure, the dependence between the width of the cutting fissure and the speed with which the laser beam moves and the total thickness of the stack of veneer sheets, the application of the laser for cutting various patterns. Computer aided designing and computer steering of the laser beam enables fast and precise production of large numbers of inlay elements not only from wood but also from other materials like glass, stone, metal, etc. Taking into consideration the high running cost of such a laser set and its very big production only few factories or even one factory in the given area could produce inlay ready for gluing. Further investigation should be carried out on this field particularly considering the lowering of costs not only in inlay production but generally where cutting of wood is concerned.

  8. Plane waves as tractor beams

    NASA Astrophysics Data System (ADS)

    Forgács, Péter; Lukács, Árpád; Romańczukiewicz, Tomasz

    2013-12-01

    It is shown that in a large class of systems, plane waves act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode carrying more momentum, in which case excess momentum is created behind the scatterer. This tractor beam or negative radiation pressure (NRP) effect, is found to be generic in systems with multiple scattering channels. In a birefringent medium, electromagnetic plane waves incident on a thin plate exert NRP of the same order of magnitude as optical radiation pressure, while in artificial dielectrics (metamaterials), the magnitude of NRP can even be macroscopic. In two dimensions, we study various scattering situations on vortices, and NRP is shown to occur by the scattering of heavy baryons into light leptons off cosmic strings, and by neutron scattering off vortices in the XY model.

  9. Explosive plane-wave lens

    DOEpatents

    Marsh, Stanley P.

    1988-01-01

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.

  10. Explosive plane-wave lens

    DOEpatents

    Marsh, S.P.

    1988-03-08

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

  11. Explosive plane-wave lens

    DOEpatents

    Marsh, S.P.

    1987-03-12

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

  12. The Laplace Planes of Uranus and Pluto

    NASA Technical Reports Server (NTRS)

    Dobrovolskis, Anthony R.

    1993-01-01

    Satellite orbits close to an oblate planet precess about its equatorial plane, while distant satellites precess around the plane of the planet's heliocentric orbit. In between, satellites in nearly circular orbits precess about a warped intermediate surface called the Laplace 'plane.' Herein we derive general formulas for locating the Laplace plane. Because Uranus and Pluto have high obliquities, their Laplace planes are severely warped. We present maps of these Laplace planes, of interest in telescopic searches for new satellites. The Laplace plane of the Solar System as a whole is similarly distorted, but comets in the inner Oort cloud precess too slowly to sense the Laplace plane.

  13. Plane waves in noncommutative fluids

    NASA Astrophysics Data System (ADS)

    Abdalla, M. C. B.; Holender, L.; Santos, M. A.; Vancea, I. V.

    2013-08-01

    We study the dynamics of the noncommutative fluid in the Snyder space perturbatively at the first order in powers of the noncommutative parameter. The linearized noncommutative fluid dynamics is described by a system of coupled linear partial differential equations in which the variables are the fluid density and the fluid potentials. We show that these equations admit a set of solutions that are monochromatic plane waves for the fluid density and two of the potentials and a linear function for the third potential. The energy-momentum tensor of the plane waves is calculated.

  14. Space-Plane Spreadsheet Program

    NASA Technical Reports Server (NTRS)

    Mackall, Dale

    1993-01-01

    Basic Hypersonic Data and Equations (HYPERDATA) spreadsheet computer program provides data gained from three analyses of performance of space plane. Equations used to perform analyses derived from Newton's second law of physics, derivation included. First analysis is parametric study of some basic factors affecting ability of space plane to reach orbit. Second includes calculation of thickness of spherical fuel tank. Third produces ratio between volume of fuel and total mass for each of various aircraft. HYPERDATA intended for use on Macintosh(R) series computers running Microsoft Excel 3.0.

  15. TransCut: interactive rendering of translucent cutouts.

    PubMed

    Li, Dongping; Sun, Xin; Ren, Zhong; Lin, Stephen; Tong, Yiying; Guo, Baining; Zhou, Kun

    2013-03-01

    We present TransCut, a technique for interactive rendering of translucent objects undergoing fracturing and cutting operations. As the object is fractured or cut open, the user can directly examine and intuitively understand the complex translucent interior, as well as edit material properties through painting on cross sections and recombining the broken pieces—all with immediate and realistic visual feedback. This new mode of interaction with translucent volumes is made possible with two technical contributions. The first is a novel solver for the diffusion equation (DE) over a tetrahedral mesh that produces high-quality results comparable to the state-of-art finite element method (FEM) of Arbree et al. but at substantially higher speeds. This accuracy and efficiency is obtained by computing the discrete divergences of the diffusion equation and constructing the DE matrix using analytic formulas derived for linear finite elements. The second contribution is a multiresolution algorithm to significantly accelerate our DE solver while adapting to the frequent changes in topological structure of dynamic objects. The entire multiresolution DE solver is highly parallel and easily implemented on the GPU. We believe TransCut provides a novel visual effect for heterogeneous translucent objects undergoing fracturing and cutting operations. PMID:23307612

  16. Improved analytical model for residual stress prediction in orthogonal cutting

    NASA Astrophysics Data System (ADS)

    Qi, Zhaoxu; Li, Bin; Xiong, Liangshan

    2014-09-01

    The analytical model of residual stress in orthogonal cutting proposed by Jiann is an important tool for residual stress prediction in orthogonal cutting. In application of the model, a problem of low precision of the surface residual stress prediction is found. By theoretical analysis, several shortages of Jiann's model are picked out, including: inappropriate boundary conditions, unreasonable calculation method of thermal stress, ignorance of stress constraint and cyclic loading algorithm. These shortages may directly lead to the low precision of the surface residual stress prediction. To eliminate these shortages and make the prediction more accurate, an improved model is proposed. In this model, a new contact boundary condition between tool and workpiece is used to make it in accord with the real cutting process; an improved calculation method of thermal stress is adopted; a stress constraint is added according to the volumeconstancy of plastic deformation; and the accumulative effect of the stresses during cyclic loading is considered. At last, an experiment for measuring residual stress in cutting AISI 1045 steel is conducted. Also, Jiann's model and the improved model are simulated under the same conditions with cutting experiment. The comparisons show that the surface residual stresses predicted by the improved model is closer to the experimental results than the results predicted by Jiann's model.

  17. Improved analytical model for residual stress prediction in orthogonal cutting

    NASA Astrophysics Data System (ADS)

    Qi, Zhaoxu; Li, Bin; Xiong, Liangshan

    2014-09-01

    The analytical model of residual stress in orthogonal cutting proposed by Jiann is an important tool for residual stress prediction in orthogonal cutting. In application of the model, a problem of low precision of the surface residual stress prediction is found. By theoretical analysis, several shortages of Jiann's model are picked out, including: inappropriate boundary conditions, unreasonable calculation method of thermal stress, ignorance of stress constraint and cyclic loading algorithm. These shortages may directly lead to the low precision of the surface residual stress prediction. To eliminate these shortages and make the prediction more accurate, an improved model is proposed. In this model, a new contact boundary condition between tool and workpiece is used to make it in accord with the real cutting process; an improved calculation method of thermal stress is adopted; a stress constraint is added according to the volume-constancy of plastic deformation; and the accumulative effect of the stresses during cyclic loading is considered. At last, an experiment for measuring residual stress in cutting AISI 1045 steel is conducted. Also, Jiann's model and the improved model are simulated under the same conditions with cutting experiment. The comparisons show that the surface residual stresses predicted by the improved model is closer to the experimental results than the results predicted by Jiann's model.

  18. Fast 4D segmentation of large datasets using graph cuts

    NASA Astrophysics Data System (ADS)

    Lombaert, Herve; Sun, Yiyong; Cheriet, Farida

    2011-03-01

    In this paper, we propose to use 4D graph cuts for the segmentation of large spatio-temporal (4D) datasets. Indeed, as 4D datasets grow in popularity in many clinical areas, so will the demand for efficient general segmentation algorithms. The graph cuts method1 has become a leading method for complex 2D and 3D image segmentation in many applications. Despite a few attempts2-5 in 4D, the use of graph cuts on typical medical volume quickly exceeds today's computer capacities. Among all existing graph cuts based methods6-10 the multilevel banded graph cuts9 is the fastest and uses the least amount of memory. Nevertheless, this method has its limitation. Memory becomes an issue when using large 4D volume sequences, and small structures become hardly recoverable when using narrow bands. We thus improve the boundary refinement efficiency by using a 4D competitive region growing. First, we construct a coarse graph at a low resolution with strong temporal links to prevent the shrink bias inherent to the graph cuts method. Second, we use a competitive region growing using a priority queue to capture all fine details. Leaks are prevented by constraining the competitive region growing within a banded region and by adding a viscosity term. This strategy yields results comparable to the multilevel banded graph cuts but is faster and allows its application to large 4D datasets. We applied our method on both cardiac 4D MRI and 4D CT datasets with promising results.

  19. Tooth profile analysiis of circular-cut, spiral-bevel gears

    NASA Technical Reports Server (NTRS)

    Huston, R. L.; Lin, Y.; Coy, J. J.

    1982-01-01

    An analysis of tooth profile changes in the transverse plane of circular-cut, spiral-bevel crown gears is presented. The analysis assumes a straight-line profile in the mid-transverse plane. The profile variation along the centerline is determined by using expressions for the variation of the spiral angle along the tooth centerline, together with the profile description at the mid-transverse plane. It is shown that the tooth surface is a hyperboloid and that significant variations in the pressure angle are possible.

  20. The Nichols Wing Cutting Equipment

    NASA Technical Reports Server (NTRS)

    Ford, James B

    1923-01-01

    Described here is wing cutting equipment for the economical production of metal wings for wind tunnel models. The machine will make any size of constant-section wing or strut up to one-sixth inch chord by 36-inch span and up to a thickness of one and one-quarter inches. It cuts a smooth, true model that is accurate to within two-thousandths of an inch on any ordinate. The holding jaws are so designed as to leave the model free of chip marks, and the only hand finishing necessary after the cutting is a rub with amunite to remove burrs. The actual change on ordinate in this finishing rub is less than .0002 inches.

  1. Stresses in ultrasonically assisted bone cutting

    NASA Astrophysics Data System (ADS)

    Alam, K.; Mitrofanov, A. V.; Bäker, M.; Silberschmidt, V. V.

    2009-08-01

    Bone cutting is a frequently used procedure in the orthopaedic surgery. Modern cutting techniques, such as ultrasonic assisted drilling, enable surgeons to perform precision operations in facial and spinal surgeries. Advanced understanding of the mechanics of bone cutting assisted by ultrasonic vibration is required to minimise bone fractures and to optimise the technique performance. The paper presents results of finite element simulations on ultrasonic and conventional bone cutting analysing the effects of ultrasonic vibration on cutting forces and stress distribution. The developed model is used to study the effects of cutting and vibration parameters (e.g. amplitude and frequency) on the stress distributions in the cutting region.

  2. Hypervelocity cutting machine and method

    DOEpatents

    Powell, J.R.; Reich, M.

    1996-11-12

    A method and machine are provided for cutting a workpiece such as concrete. A gun barrel is provided for repetitively loading projectiles therein and is supplied with a pressurized propellant from a storage tank. A thermal storage tank is disposed between the propellant storage tank and the gun barrel for repetitively receiving and heating propellant charges which are released in the gun barrel for repetitively firing projectiles therefrom toward the workpiece. In a preferred embodiment, hypervelocity of the projectiles is obtained for cutting the concrete workpiece by fracturing thereof. 10 figs.

  3. Hypervelocity cutting machine and method

    DOEpatents

    Powell, James R.; Reich, Morris

    1996-11-12

    A method and machine 14 are provided for cutting a workpiece 12 such as concrete. A gun barrel 16 is provided for repetitively loading projectiles 22 therein and is supplied with a pressurized propellant from a storage tank 28. A thermal storage tank 32,32A is disposed between the propellant storage tank 28 and the gun barrel 16 for repetitively receiving and heating propellant charges which are released in the gun barrel 16 for repetitively firing projectiles 22 therefrom toward the workpiece 12. In a preferred embodiment, hypervelocity of the projectiles 22 is obtained for cutting the concrete workpiece 12 by fracturing thereof.

  4. Nurses cut health care costs.

    PubMed

    Dunham-Taylor, J; Oldaker, J; DeCapua, T; Manley, N K; Oprian, B; Wrestler, J

    1993-12-01

    Nurses are a value-added and cost-savings component of health care, yet others frequently impede nurse efforts. Nurses, coupled with business, can contribute to cutting health care costs by (a) increasing dialogue with business leaders on effective cost-cutting measures across health care, (b) supporting nurse leaders who are capable of administering key community positions, (c) involving whole communities in wellness/health promotion and/or disease prevention programs, (d) encouraging more home health care alternatives; and (e) supporting nurse-related entrepreneurial efforts. PMID:8228142

  5. Microbiopsy/precision cutting devices

    DOEpatents

    Krulevitch, P.A.; Lee, A.P.; Northrup, M.A.; Benett, W.J.

    1999-07-27

    Devices are disclosed for performing tissue biopsy on a small scale (microbiopsy). By reducing the size of the biopsy tool and removing only a small amount of tissue or other material in a minimally invasive manner, the risks, costs, injury and patient discomfort associated with traditional biopsy procedures can be reduced. By using micromachining and precision machining capabilities, it is possible to fabricate small biopsy/cutting devices from silicon. These devices can be used in one of four ways (1) intravascularly, (2) extravascularly, (3) by vessel puncture, and (4) externally. Additionally, the devices may be used in precision surgical cutting. 6 figs.

  6. Female genital cutting: nursing implications.

    PubMed

    Goldenstein, Rachel A

    2014-01-01

    Female genital cutting (FGC) is a practice that affects millions of girls and women worldwide. This deeply rooted practice has cultural, religious, and psychosexual meaning to its practitioners, but it also carries long-term physical and mental complications. Decried as a human rights violation, nonetheless this practice is still carried out today. Nurses are in a unique position to contact and educate women who have been cut or are at risk for mutilation. To advocate for these women, a thorough understanding of the practice of FGC, its cultural overtones, religious implications, and psychosexual effects is needed. PMID:23835896

  7. Microbiopsy/precision cutting devices

    DOEpatents

    Krulevitch, Peter A.; Lee, Abraham P.; Northrup, M. Allen; Benett, William J.

    1999-01-01

    Devices for performing tissue biopsy on a small scale (microbiopsy). By reducing the size of the biopsy tool and removing only a small amount of tissue or other material in a minimally invasive manner, the risks, costs, injury and patient discomfort associated with traditional biopsy procedures can be reduced. By using micromachining and precision machining capabilities, it is possible to fabricate small biopsy/cutting devices from silicon. These devices can be used in one of four ways 1) intravascularly, 2) extravascularly, 3) by vessel puncture, and 4) externally. Additionally, the devices may be used in precision surgical cutting.

  8. Affine Contractions on the Plane

    ERIC Educational Resources Information Center

    Celik, D.; Ozdemir, Y.; Ureyen, M.

    2007-01-01

    Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…

  9. Support plane method applied to ground objects recognition using modelled SAR images

    NASA Astrophysics Data System (ADS)

    Zherdev, Denis A.; Fursov, Vladimir A.

    2015-09-01

    In this study, the object recognition problem was solved using support plane method. The modelled SAR images were used as features vectors in the recognition algorithm. Radar signal backscattering of objects in different observing poses is presented in SAR images. For real time simulation, we used simple mixture model of Lambertian-specular reflectivity. To this end, an algorithm of ray tracing is extended for simulating SAR images of 3D man-made models. The suggested algorithm of support plane is very effective in objects recognition using SAR images and RCS diagrams.

  10. Multiple-image encryption with bit-plane decomposition and chaotic maps

    NASA Astrophysics Data System (ADS)

    Tang, Zhenjun; Song, Juan; Zhang, Xianquan; Sun, Ronghai

    2016-05-01

    Image encryption is an efficient technique of image content protection. In this work, we propose a useful image encryption algorithm for multiple grayscale images. The proposed algorithm decomposes input images into bit-planes, randomly swaps bit-blocks among different bit-planes, and conducts XOR operation between the scrambled images and secret matrix controlled by chaotic map. Finally, an encrypted PNG image is obtained by viewing four scrambled grayscale images as its red, green, blue and alpha components. Many simulations are done to illustrate efficiency of our algorithm.

  11. Laser performance and thermal lensing in flashlamp pumped N p-cut and N g-cut Nd:KGW crystals

    NASA Astrophysics Data System (ADS)

    Loiko, P. A.; Denisov, I. A.; Yumashev, K. V.; Kuleshov, N. V.; Pavlyuk, A. A.

    2010-09-01

    A comparative experimental study of laser performance and thermal lensing properties in a flashlamp pumped Nd:KGW crystal cut for the light propagating along the optical indicatrix axes N p and N g is presented. It was found that for both, the N p-cut Nd:KGW and N g-cut Nd:KGW thermal lens is astigmatic with astigmatism degree being determined mainly by the thermal expansion anisotropy in KGW. The thermal lens in the N g-cut Nd:KGW is positive, while in the N p-cut Nd:KGW it has different signs for rays lying in two different meridional planes. The sensitivity factors show how much the thermal lens optical power of a laser rod changes with pump power are determined. The results show that the N g-cut Nd:KGW allows one to obtain higher average output powers at high pump levels as compared to the N p-cut Nd:KGW.

  12. Small-size measuring gauges for metal cutting machine tools

    NASA Astrophysics Data System (ADS)

    Levin, B. M.; Lyapkov, V. N.; Myasnikov, Y. A.; Kirsanova, L. N.

    1984-02-01

    Recently two new models of suspension type optical measuring gauges have been developed with a 0.01 mm scale division, for measuring displacements of movable parts in metal cutting machine tools. The first one is the IG-98 consisting of an STs-80 incandescent lamp, a light filter, two reference rulers, two objectives, a light splitter cube, four plane mirrors, two condenser lenses, a graduated circle and a magnifying glass. The second one is the IG-119 consisting of an STs-61 incandescent lamp, a light filter, a rectangular prism with cover, two reference rulers, two objectives, a light splitter cube, one mirror, one condenser lens, a cylindrical shield and a magnifying glass. A complete accuracy analysis of both instruments indicates that two out of the seven principal error components are negligible, namely the angular error of the null adjustment guides and the temperature error referred to the plane of one of the reference rulers.

  13. Hydrogen platelets in crystalline silicon - Precursors for the "smart cut"

    SciTech Connect

    Reboredo, Fernando A; Pantelides, Sokrates T

    1999-01-01

    High concentrations of H in crystalline Si are known to induce planar defects (platelets), primarily in the (100) and the (Ill)planes. These platelets are precursors for the so-called "smart cut" technique for fabricating Silicon-On-insulator (SOI) structures. The atomic-scale mechanisms for the nucleation and growth of the H-induced platelets and many other experimental observations have remained elusive. We review recent extensive first-principles calculations in terms of which a comprehensive picture of platelet nucleation and growth has emerged. The theory naturally accounts for the observed preference for (111) and (100) planes, for H release and trapping of H-2 molecules, and other observations. The platelets are arrays of second-neighbor hydrogenated vacancies that do not bind to each other, but their formation is due to energetically preferred reaction pathways.

  14. Effect of Planning on Trunk Motion and Knee Moments During a Side Step Cut Task

    NASA Astrophysics Data System (ADS)

    Houck, Jeff; Gorniak, Stacey; Nicholson, Kristen

    2004-03-01

    Recent studies suggest that alterations in knee biomechanics associated with unanticipated cutting tasks place athletes at higher risk of knee injuries. Besier et al observed alterations in knee moments during unanticipated cutting tasks that were consistent with in-vitro ACL injury mechanisms. During similar tasks, Patla et al observed lateral trunk lean and decreased foot placement, suggesting that full body center of mass control is perturbed during such tasks. The purpose of this study was to compare the trunk and knee frontal plane moments and evaluate a relationship between the two during unanticipated cutting tasks. The results of this study suggest that there is a relationship between the trunk and knee frontal plane moments during the first 200-400ms of the stance phase of gait.

  15. Automated internal pipe cutting device

    DOEpatents

    Godlewski, William J.; Haffke, Gary S.; Purvis, Dale; Bashar, Ronald W.; Jones, Stewart D.; Moretti, Jr., Henry; Pimentel, James

    2003-01-21

    The invention is a remotely controlled internal pipe cutting device primarily used for cutting pipes where the outside of the pipe is inaccessible at the line where the cut is to be made. The device includes an axial ram within a rotational cylinder which is enclosed in a housing. The housing is adapted for attachment to an open end of the pipe and for supporting the ram and cylinder in cantilever fashion within the pipe. A radially movable cutter, preferably a plasma arc torch, is attached to the distal end of the ram. A drive mechanism, containing motors and mechanical hardware for operating the ram and cylinder, is attached to the proximal end of the housing. The ram and cylinder provide for moving the cutter axially and circumferentially, and a cable assembly attached to a remote motor provide for the movement of the cutter radially, within the pipe. The control system can be adjusted and operated remotely to control the position and movement of the cutter to obtain the desired cut. The control system can also provide automatic standoff control for a plasma arc torch.

  16. The Cutting-Edge Challenge

    ERIC Educational Resources Information Center

    Share, Joani

    2005-01-01

    In a time of educational budget cuts, the arts seem to take the major brunt of the financial ax. Fine arts programs are often pitted against one another for survival. The music industry and supporting corporations, such as American Express, campaign to have instruments donated or purchased to keep educational programs alive. The visual arts do not…

  17. Anatomy of a Budget Cut.

    ERIC Educational Resources Information Center

    Quinn, Cheri L.

    2003-01-01

    Story of Empire School District (Oklahoma) school board's decision to cut the budget in the mid-1980s, including the elimination of the popular music and band program and termination of its director, a decision that caused considerable community conflict resulting in the defeat of all the incumbent board members at the polls and the resignation of…

  18. Petrophysical corner - calculating water cut

    SciTech Connect

    Elphick, R.Y. )

    1990-02-01

    The problem of determining the amount of water cut that can be expected from a well is discussed in conjunction with a program for making this calculation. The program was written for Amiga, Apple Macintosh, and MS DOS personal computers and source code for the program is provided.

  19. Model aids cuttings transport prediction

    SciTech Connect

    Gavignet, A.A. ); Sobey, I.J. )

    1989-09-01

    Drilling of highly deviated wells can be complicated by the formation of a thick bed of cuttings at low flow rates. The model proposed in this paper shows what mechanisms control the thickness of such a bed, and the model predictions are compared with experimental results.

  20. Optimization of starshades: focal plane versus pupil plane

    NASA Astrophysics Data System (ADS)

    Flamary, R.; Aime, C.

    2014-09-01

    We search for the best possible transmission for an external occulter coronagraph that is dedicated to the direct observation of terrestrial exoplanets. We show that better observation conditions are obtained when the flux in the focal plane is minimized in the zone in which the exoplanet is observed, instead of for the total flux received by the telescope. We describe the transmission of the occulter as a sum of basis functions. For each element of the basis, we numerically computed the Fresnel diffraction at the aperture of the telescope and the complex amplitude at its focus. The basis functions are circular disks that are linearly apodized over a few centimeters (truncated cones). We complemented the numerical calculation of the Fresnel diffraction for these functions by a comparison with pure circular disks (cylinder) for which an analytical expression, based on a decomposition in Lommel series, is available. The technique of deriving the optimal transmission for a given spectral bandwidth is a classical regularized quadratic minimization of intensities, but linear optimizations can be used as well. Minimizing the integrated intensity on the aperture of the telescope or for selected regions of the focal plane leads to slightly different transmissions for the occulter. For the focal plane optimization, the resulting residual intensity is concentrated behind the geometrical image of the occulter, in a blind region for the observation of an exoplanet, and the level of background residual starlight becomes very low outside this image. Finally, we provide a tolerance analysis for the alignment of the occulter to the telescope, which also favors the focal plane optimization. This means that telescope offsets of a few decimeters do not strongly reduce the efficiency of the occulter.

  1. An automatic and fast centerline extraction algorithm for virtual colonoscopy.

    PubMed

    Jiang, Guangxiang; Gu, Lixu

    2005-01-01

    This paper introduces a new refined centerline extraction algorithm, which is based on and significantly improved from distance mapping algorithms. The new approach include three major parts: employing a colon segmentation method; designing and realizing a fast Euclidean Transform algorithm and inducting boundary voxels cutting (BVC) approach. The main contribution is the BVC processing, which greatly speeds up the Dijkstra algorithm and improves the whole performance of the new algorithm. Experimental results demonstrate that the new centerline algorithm was more efficient and accurate comparing with existing algorithms. PMID:17281406

  2. A program to compute EM scattering of plane wave by a perfectly conducting half-plane in a finitely conducting layered half-space

    NASA Astrophysics Data System (ADS)

    Caleb Dhanasekaran, P.; Poddar, M.

    A FORTRAN program utilizing an integral equation calculates 10 field quantities relating to the electromagnetic (EM) scattering of plane wave by a perfectly conducting half-plane buried in a finitely conducting layered half-space. The computing algorithm is executable on a computer of small storage capacity such as PDP 11/40 and as such is useful to many exploration scientists without the facility of a mainframe computer, for computing model curves to interpret field data.

  3. CO2-Laser Cutting Fiber Reinforced Polymers

    NASA Astrophysics Data System (ADS)

    Mueller, R.; Nuss, Rudolf; Geiger, Manfred

    1989-10-01

    Guided by experimental investigations laser cutting of glass fiber reinforced reactive injection moulded (RRIM)-polyurethanes which are used e.g. in car industry for bumpers, spoilers, and further components is described. A Comparison with other cutting techniques as there are water jet cutting, milling, punching, sawing, cutting with conventional knife and with ultrasonic excited knife is given. Parameters which mainly influence cutting results e.g. laser power, cutting speed, gas nature and pressure will be discussed. The problematic nature in characterising micro and macro geometry of laser cut edges of fiber reinforced plastic (FRP) is explained. The topography of cut edges is described and several characteristic values are introduced to specify the obtained working quality. The surface roughness of laser cut edges is measured by both, an optical and a mechanical sensor and their reliabilities are compared.

  4. Knife and impact cutting of lamb bone.

    PubMed

    King, M J

    1999-05-01

    The forces and hence fracture energies required to cut bone are presented in this paper and the merits of cutting with a high speed blade are considered. A plain knife blade was used to cut cancellous and compact lamb bone using three different methods. A microtome was used to produce a range of cut thicknesses which enabled the fracture energy to be separated into friction, surface fracture and plastic deformation energies. A tensile test machine was used to produce thicker off-cuts so that the energy required to cut through full sections of bone could be determined. A high speed rail gun was used to cut at speeds up to 130 m/s. The energy required to cut bone did not change with blade speed. However, the energies measured during the cutting varied over a wide range. In situations in which the surface of the cut bone exhibited a very uneven surface high energy was required, whereas when the resulting cut surface was planar the cutting energy was low. A light weight blade which impacts the bone at high speed will transmit a small impulse to the carcass which may be absorbed without transmitting strain to the muscle/connective tissue. This may allow the development of a high speed knife which will cut bone without excessively damaging the meat surrounding the cut. PMID:22062140

  5. Plane Wave and Coulomb Asymptotics

    NASA Astrophysics Data System (ADS)

    Mulligan, P. G.; Crothers, D. S. F.

    2004-01-01

    A simple plane wave solution of the Schrödinger Helmholtz equation is a quantum eigenfunction obeying both energy and linear momentum correspondence principles. Inclusion of the outgoing wave with scattering amplitude f obeys unitarity and the optical theorem. By closely considering the standard asymptotic development of the plane wave, we show that there is a problem with angular momentum when we consider forward scattering at the point of closest approach and at large impact parameter given semiclassically by (l + 1/2)/k where l is the azimuthal quantum number and may be large (J Leech et al, Phys. Rev. Lett. 88 257901 (2002)). The problem is resolved via non-uniform, non-standard analysis involving the Heaviside step function, unifying classical, semiclassical and quantum mechanics, and the treatment is extended to the case of pure Coulomb scattering.

  6. Eight plane IPND mechanical testing.

    SciTech Connect

    Zhao, A.; Guarino, V.; Wood, K.; Nephew, T.; Ayres, D.; Lee, A.; High Energy Physics; FNAL

    2008-03-18

    A mechanical test of an 8 plane IPND mechanical prototype, which was constructed using extrusions from the testing/tryout of the 16 cell prototype extrusion die in Argonne National Laboratory, was conducted. There were 4 vertical and 4 horizontal planes in this 8 plane IPND prototype. Each vertical plane had four 16 cell extrusions, while each horizontal plane had six 16 cell extrusions. Each plane was glued together using the formulation of Devcon adhesive, Devcon 60. The vertical extrusions used in the vertical planes shares the same dimensions as the horizontal extrusions in the horizontal planes with the average web thickness of 2.1 mm and the average wall thickness of 3.1 mm. This mechanical prototype was constructed with end-seals on the both ends of the vertical extrusions. The gaps were filled with epoxy between extrusions and end-seals. The overall dimension of IPND is 154.8 by 103.1 by 21.7 inches with the weight of approximately 1200 kg, as shown in a figure. Two similar mechanical tests of 3 layer and 11 layer prototypes have been done in order to evaluate the strength of the adhesive joint between extrusions in the NOvA detector. The test showed that the IPND prototype was able to sustain under the loading of weight of itself and scintillator. Two FEA models were built to verify the measurement data from the test. The prediction from FEA slice model seems correlated reasonably well to the test result, even under a 'rough' estimated condition for the wall thickness (from an untuned die) and an unknown property of 'garage type' extrusion. A full size of FEA 3-D model also agrees very well with the test data from strain gage readings. It is worthy to point out that the stress distribution of the structure is predominantly determined by the internal pressure, while the buckling stability relies more on the loading weight from the extrusions themselves and scintillate. Results of conducted internal pressure tests, including 3- cell, 11-cell and the IPND

  7. Laser Cutting of Thin Nickel Bellows

    NASA Technical Reports Server (NTRS)

    Butler, C. L.

    1986-01-01

    Laser cutting technique produces narrow, precise, fast, and repeatable cuts in thin nickel-allow bellows material. Laser cutting operation uses intense focused beam to melt material and assisting gas to force melted material through part thickness, creating void. When part rotated or moved longitudinally, melting and material removal continuous and creates narrow, fast, precise, and repeatable cut. Technique used to produce cuts of specified depths less than material thickness. Avoids distortion, dents, and nicks produced in delicate materials during lathe trimming operations, which require high cutting-tool pressure and holding-fixture forces.

  8. CO2 laser cutting of natural granite

    NASA Astrophysics Data System (ADS)

    Riveiro, A.; Mejías, A.; Soto, R.; Quintero, F.; del Val, J.; Boutinguiza, M.; Lusquiños, F.; Pardo, J.; Pou, J.

    2016-01-01

    Commercial black granite boards (trade name: "Zimbabwe black granite") 10 mm thick, were successfully cut by a 3.5 kW CO2 laser source. Cutting quality, in terms of kerf width and roughness of the cut wall, was assessed by means of statistically planned experiments. No chemical modification of the material in the cutting walls was detected by the laser beam action. Costs associated to the process were calculated, and the main factors affecting them were identified. Results reported here demonstrate that cutting granite boards could be a new application of CO2 laser cutting machines provided a supersonic nozzle is used.

  9. Symmetry in finite phase plane

    NASA Astrophysics Data System (ADS)

    Zak, J.

    2010-03-01

    The known symmetries in one-dimensional systems are inversion and translations. These symmetries persist in finite phase plane, but a novel symmetry arises in view of the discrete nature of the coordinate xi and the momentum pi : xi and pi can undergo permutations. Thus, if xi assumes M discrete values, i = 0, 1,2,..., M - 1, a permutation will change the order of the set x0,x1,..., xM-1 into a new ordered set. Such a symmetry element does not exist for a continuous x-coordinate in an infinite phase plane. Thus, in a finite phase plane, translations can be replaced by permutations. This is also true for the inversion operator. The new permutation symmetry has been used for the construction of conjugate representations and for the splitting of the M-dimensional vector space into independent subspaces. This splitting is exhaustive in the sense that if M = iMi with Mi being prime numbers, the M-dimensional space splits into M1,M2,...Mn-dimensional independent subspaces. It is shown that following this splitting one can design new potentials with appropriate constants of motion. A related problem is the Weyl-Heisenberg group in the M-dimensional space which turns into a direct product of its subgroups in the Mi-dimensional subspaces. As an example we consider the case of M = 8.

  10. Cutting

    MedlinePlus

    ... for Parents for Kids for Teens Teens Home Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Q& ... to do. But you can't get your mind off feeling upset, and your body has this knot of emotional pain. Before you ...

  11. C-plane Reconstructions from Sheaf Acquisition for Ultrasound Electrode Vibration Elastography

    PubMed Central

    Ingle, Atul; Varghese, Tomy

    2014-01-01

    This paper presents a novel algorithm for reconstructing and visualizing ablated volumes using radiofrequency ultrasound echo data acquired with the electrode vibration elastography approach. The ablation needle is vibrated using an actuator to generate shear wave pulses that are tracked in the ultrasound image plane at different locations away from the needle. This data is used for reconstructing shear wave velocity maps for each imaging plane. A C-plane reconstruction algorithm is proposed which estimates shear wave velocity values on a collection of transverse planes that are perpendicular to the imaging planes. The algorithm utilizes shear wave velocity maps from different imaging planes that share a common axis of intersection. These C-planes can be used to generate a 3D visualization of the ablated region. Experimental validation of this approach was carried out using data from a tissue mimicking phantom. The shear wave velocity estimates were within 20% of those obtained from a clinical scanner, and a contrast of over 4 dB was obtained between the stiff and soft regions of the phantom. PMID:25530690

  12. Determining the pivotal plane of fluid lipid membranes in simulations.

    PubMed

    Wang, Xin; Deserno, Markus

    2015-10-28

    Each leaflet of a curved lipid membrane contains a surface at which the area strain vanishes, the so-called pivotal plane. Its distance z0 from the bilayer's midplane arises in numerous contexts, for instance the connection between monolayer and bilayer moduli, stress-profile moments, or area-difference elasticity theories. Here, we propose two precise methods for determining the location of the pivotal plane in computer simulations, both of which rely on monitoring the lipid imbalance across a curved bilayer. The first method considers the ratio of lipid number between the two leaflets of cylindrical or spherical vesicles; it hence requires lipid flip-flop for equilibration. The second method looks at the leaflet difference across local sections cut out from a buckled membrane; this observable equilibrates even in the absence of flip-flop. We apply our methods to two different coarse-grained lipid models, the generic three-bead solvent-free Cooke model and a ten-bead representation of dimyristoylphosphocholine with the explicit solvent MARTINI model. The Cooke model is amenable to both methods and gives results that agree at the percent level. Using it, we also show that the pivotal plane moves outward as lipid curvature becomes more positive. The MARTINI model can only be analyzed with the buckling method; the obtained value z0 = 0.850(11) nm lies about 0.4 nm inwards of the glycerol backbone and is hence unexpectedly small. We attribute this to limitations of the coarse-grained description, suggesting that the location of the pivotal plane might be a good indicator for how well lipid models capture the microscopic origins of curvature elasticity. Finally, we also show that the pivotal plane position itself moves as the membrane is bent. The leading correction is linear in curvature, dependent on the Poisson ratio, and can matter when analyzing experimental results obtained from highly curved inverse hexagonal phases. PMID:26520500

  13. Determining the pivotal plane of fluid lipid membranes in simulations

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Deserno, Markus

    2015-10-01

    Each leaflet of a curved lipid membrane contains a surface at which the area strain vanishes, the so-called pivotal plane. Its distance z0 from the bilayer's midplane arises in numerous contexts, for instance the connection between monolayer and bilayer moduli, stress-profile moments, or area-difference elasticity theories. Here, we propose two precise methods for determining the location of the pivotal plane in computer simulations, both of which rely on monitoring the lipid imbalance across a curved bilayer. The first method considers the ratio of lipid number between the two leaflets of cylindrical or spherical vesicles; it hence requires lipid flip-flop for equilibration. The second method looks at the leaflet difference across local sections cut out from a buckled membrane; this observable equilibrates even in the absence of flip-flop. We apply our methods to two different coarse-grained lipid models, the generic three-bead solvent-free Cooke model and a ten-bead representation of dimyristoylphosphocholine with the explicit solvent MARTINI model. The Cooke model is amenable to both methods and gives results that agree at the percent level. Using it, we also show that the pivotal plane moves outward as lipid curvature becomes more positive. The MARTINI model can only be analyzed with the buckling method; the obtained value z0 = 0.850(11) nm lies about 0.4 nm inwards of the glycerol backbone and is hence unexpectedly small. We attribute this to limitations of the coarse-grained description, suggesting that the location of the pivotal plane might be a good indicator for how well lipid models capture the microscopic origins of curvature elasticity. Finally, we also show that the pivotal plane position itself moves as the membrane is bent. The leading correction is linear in curvature, dependent on the Poisson ratio, and can matter when analyzing experimental results obtained from highly curved inverse hexagonal phases.

  14. Smooth quality streaming with bit-plane labeling

    NASA Astrophysics Data System (ADS)

    Cho, Chuan-Yu; Chen, Hong-Sheng; Wang, Jia-Shung

    2005-07-01

    Bit-plane coding techniques have been proposed as an efficient way to achieve the goal of fine granularity scalability (FGS). Both in image and video coding standards such as JPEG 2000 and MPEG-4, bit-plane coding techniques have been utilized to code a universal bit-stream for various bandwidth applications. With the bit-plane coding, a bit-stream can be truncated according to the available bandwidth. Hence, the video quality can be very sensitive to the network bandwidth variation especially while streaming a video over the Internet or a wireless link. For overall human perception, a consistent and smooth quality video is much better than to have high video quality in just a short period but with highly quality variation in general. We classify the quality variation into two categories: inter-frame and intraframe quality variation. The inter-frame quality variation may cause by the constant bit rate coded (CBR) base layer video or the network bandwidth variation, while the intra-frame quality variation causes mainly by the various motion types. For example, moving objects are usually more difficult to be encoded. This paper focuses on the inter-frame quality variation because quality variation is more significant between frames than within a frame. An enhancement layer labeling algorithm is proposed to reduce the inter-frame quality variation, and a dynamic bit-plane truncation scheme is utilized to maintain the smooth streaming video quality. The proposed algorithm has no overhead in the decoder, and the experimental results portray that our proposed algorithm can greatly eliminate the inter-frame quality variation.

  15. A Cartesian cut cell method for rarefied flow simulations around moving obstacles

    NASA Astrophysics Data System (ADS)

    Dechristé, G.; Mieussens, L.

    2016-06-01

    For accurate simulations of rarefied gas flows around moving obstacles, we propose a cut cell method on Cartesian grids: it allows exact conservation and accurate treatment of boundary conditions. Our approach is designed to treat Cartesian cells and various kinds of cut cells by the same algorithm, with no need to identify the specific shape of each cut cell. This makes the implementation quite simple, and allows a direct extension to 3D problems. Such simulations are also made possible by using an adaptive mesh refinement technique and a hybrid parallel implementation. This is illustrated by several test cases, including a 3D unsteady simulation of the Crookes radiometer.

  16. Improved interframe registration based nonuniformity correction for focal plane arrays

    NASA Astrophysics Data System (ADS)

    Zuo, Chao; Chen, Qian; Gu, Guohua; Sui, Xiubao; Ren, Jianle

    2012-07-01

    In this paper, an improved interframe registration based nonuniformity correction algorithm for focal plane arrays is proposed. The method simultaneously estimates detector parameters and carries out the nonuniformity correction by minimizing the mean square error between the two properly registered image frames. A new masked phase correlation algorithm is introduced to obtain reliable shift estimates in the presence of fixed pattern noise. The use of an outliers exclusion scheme, together with a variable step size strategy, could not only promote the correction precision considerably, but also eliminate ghosting artifacts effectively. The performance of the proposed algorithm is evaluated with clean infrared image sequences with simulated nonuniformity and real pattern noise. We also apply the method to a real-time imaging system to show how effective it is in reducing noise and the ghosting artifacts.

  17. AK-cut crystal resonators

    NASA Technical Reports Server (NTRS)

    Kahan, A.; Euler, F. K.

    1983-01-01

    Calculations have predicted the existence of crystallographically doubly rotated quartz orientations with turnover temperatures which are considerably less sensitive to angular misorientation then comparable AT- or BT-cuts. These crystals are arbitrarily designated as the AK-cut. Experimental data is given for seven orientations, phi-angle variations between 30-46 deg and theta-angle variations between 21-28 deg measured on 3.3-3.4 MHz fundamental mode resonators vibrating in the thickness shear c-mode. The experimental turnover temperatures of these resonators are between 80 C and 150 C, in general agreement with calculated values. The normalized frequency change as a function of temperature has been fitted with a cubic equation.

  18. STRUCTURAL ANNOTATION OF EM IMAGES BY GRAPH CUT

    SciTech Connect

    Chang, Hang; Auer, Manfred; Parvin, Bahram

    2009-05-08

    Biological images have the potential to reveal complex signatures that may not be amenable to morphological modeling in terms of shape, location, texture, and color. An effective analytical method is to characterize the composition of a specimen based on user-defined patterns of texture and contrast formation. However, such a simple requirement demands an improved model for stability and robustness. Here, an interactive computational model is introduced for learning patterns of interest by example. The learned patterns bound an active contour model in which the traditional gradient descent optimization is replaced by the more efficient optimization of the graph cut methods. First, the energy function is defined according to the curve evolution. Next, a graph is constructed with weighted edges on the energy function and is optimized with the graph cut algorithm. As a result, the method combines the advantages of the level set method and graph cut algorithm, i.e.,"topological" invariance and computational efficiency. The technique is extended to the multi-phase segmentation problem; the method is validated on synthetic images and then applied to specimens imaged by transmission electron microscopy(TEM).

  19. Metal cutting simulation of 4340 steel using an accurate mechanical description of meterial strength and fracture

    SciTech Connect

    Maudlin, P.J.; Stout, M.G.

    1996-09-01

    Strength and fracture constitutive relationships containing strain rate dependence and thermal softening are important for accurate simulation of metal cutting. The mechanical behavior of a hardened 4340 steel was characterized using the von Mises yield function, the Mechanical Threshold Stress model and the Johnson- Cook fracture model. This constitutive description was implemented into the explicit Lagrangian FEM continuum-mechanics code EPIC, and orthogonal plane-strain metal cutting calculations were performed. Heat conduction and friction at the toolwork-piece interface were included in the simulations. These transient calculations were advanced in time until steady state machining behavior (force) was realized. Experimental cutting force data (cutting and thrust forces) were measured for a planning operation and compared to the calculations. 13 refs., 6 figs.

  20. Reservoir management cost-cutting

    SciTech Connect

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  1. Drill cuttings mount formation study

    NASA Astrophysics Data System (ADS)

    Teh, Su Yean; Koh, Hock Lye

    2014-07-01

    Oil, Gas and Energy sector has been identified as an essential driving force in the Malaysian Economic Transformation Programs (ETP). Recently confirmed discovery of many offshore oil and gas deposits in Malaysian waters has ignited new confidence in this sector. However, this has also spurred intense interest on safeguarding the health and environment of coastal waters in Malaysia from adverse impact resulting from offshore oil and gas production operation. Offshore discharge of spent drilling mud and rock cuttings is the least expensive and simplest option to dispose of large volumes of drilling wastes. But this onsite offshore disposal may have adverse environmental impacts on the water column and the seabed. It may also pose occupational health hazards to the workers living in the offshore platforms. It is therefore important to model the transport and deposition of drilling mud and rock cuttings in the sea to enable proper assessment of their adverse impacts on the environment and the workers. Further, accumulation of drill particles on the seabed may impede proper operation of pipelines on the seabed. In this paper, we present an in-house application model TUNA-PT developed to cater to local oil and gas industry needs to simulate the dispersion and mount formation of drill cuttings by offshore oil and gas exploration and production platforms. Using available data on Malaysian coastal waters, simulation analyses project a pile formation on the seabed with a maximum height of about 1 m and pile radius of around 30 to 50 m. Simulated pile heights are not sensitive to the heights of release of the cuttings as the sensitivity has been mitigated by the depth of water.

  2. Quantum algorithms

    NASA Astrophysics Data System (ADS)

    Abrams, Daniel S.

    This thesis describes several new quantum algorithms. These include a polynomial time algorithm that uses a quantum fast Fourier transform to find eigenvalues and eigenvectors of a Hamiltonian operator, and that can be applied in cases (commonly found in ab initio physics and chemistry problems) for which all known classical algorithms require exponential time. Fast algorithms for simulating many body Fermi systems are also provided in both first and second quantized descriptions. An efficient quantum algorithm for anti-symmetrization is given as well as a detailed discussion of a simulation of the Hubbard model. In addition, quantum algorithms that calculate numerical integrals and various characteristics of stochastic processes are described. Two techniques are given, both of which obtain an exponential speed increase in comparison to the fastest known classical deterministic algorithms and a quadratic speed increase in comparison to classical Monte Carlo (probabilistic) methods. I derive a simpler and slightly faster version of Grover's mean algorithm, show how to apply quantum counting to the problem, develop some variations of these algorithms, and show how both (apparently distinct) approaches can be understood from the same unified framework. Finally, the relationship between physics and computation is explored in some more depth, and it is shown that computational complexity theory depends very sensitively on physical laws. In particular, it is shown that nonlinear quantum mechanics allows for the polynomial time solution of NP-complete and #P oracle problems. Using the Weinberg model as a simple example, the explicit construction of the necessary gates is derived from the underlying physics. Nonlinear quantum algorithms are also presented using Polchinski type nonlinearities which do not allow for superluminal communication. (Copies available exclusively from MIT Libraries, Rm. 14- 0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

  3. Fabrication of a Cryogenic Bias Filter for Ultrasensitive Focal Plane

    NASA Technical Reports Server (NTRS)

    Chervenak, James; Wollack, Edward

    2012-01-01

    A fabrication process has been developed for cryogenic in-line filtering for the bias and readout of ultrasensitive cryogenic bolometers for millimeter and submillimeter wavelengths. The design is a microstripline filter that cuts out, or strongly attenuates, frequencies (10 50 GHz) that can be carried by wiring staged at cryogenic temperatures. The filter must have 100-percent transmission at DC and low frequencies where the bias and readout lines will carry signal. The fabrication requires the encapsulation of superconducting wiring in a dielectric-metal envelope with precise electrical characteristics. Sufficiently thick insulation layers with high-conductivity metal layers fully surrounding a patterned superconducting wire in arrayable formats have been demonstrated. A degenerately doped silicon wafer has been chosen to provide a metallic ground plane. A metallic seed layer is patterned to enable attachment to the ground plane. Thick silicon dioxide films are deposited at low temperatures to provide tunable dielectric isolation without degrading the metallic seed layer. Superconducting wiring is deposited and patterned using microstripline filtering techniques to cut out the relevant frequencies. A low Tc superconductor is used so that it will attenuate power strongly above the gap frequency. Thick dielectric is deposited on top of the circuit, and then vias are patterned through both dielectric layers. A thick conductive film is deposited conformally over the entire circuit, except for the contact pads for the signal and bias attachments to complete the encapsulating ground plane. Filters are high-aspect- ratio rectangles, allowing close packing in one direction, while enabling the chip to feed through the wall of a copper enclosure. The chip is secured in the copper wall using a soft metal seal to make good thermal and electrical contact to the outer shield.

  4. Quantitative laser cutting of plants

    NASA Astrophysics Data System (ADS)

    Schou, Juergen; Heisel, Torben; Nordskov, Arne; Christensen, Svend; Jensen, Peter S.; Thestrup, Birgitte; Toftmann, Bo

    2002-09-01

    It is possible to quantify cutting of plant stems by a laser beam in contrast to mechanical cutting. The biomass of the plants after a certain period under standard green house conditions was used to measure the effect of partial or complete cutting with a laser. Continuous laser irradiation at 10.6 micrometers of the plant stem turned out to be very efficient at values of the energy per width unit above 6 J/mm. The effect of laser irradiation at 355 nm or 1064 nm is less pronounced, but also at these wavelengths the re- growth or continuous growth are reduced. A monocotyledon- type, winter what (Triticum vulgare L), is substantially more resistant than a dicotyledon-type, charlock (Chenopodium album L.) against radiation. The exposure limits for laser light in living plants have been explored as well. The limit in terms of re-growth of the irradiated plants exceeds the MPE (maximum permissible exposure) of human skin by several orders of magnitude. The consequence is that very powerful (unfocused) lasers can be used in any environment without significant impact on living plants.

  5. Angular Stability Margins for the Remote Fusion Cutting Process

    NASA Astrophysics Data System (ADS)

    Villumsen, Sigurd; Kristiansen, Morten

    The set of incident angles, that yields stable cuts when conducting remote fusion cutting (RFC), is of great importance when scheduling multiple cuts on a work piece. This is due to their ability to determine how much the laser beam can be moved by angling the cutting head instead of translating it. This paper investigates how the stability of the RFC process is affected by changing the incident angle when processing stainless steel sheets. This investigation was conducted as an experimental study in which the angle of incidence was decomposed into a work angle and a travel angle. The stability was evaluated by an automatic procedure based on images acquired by a programmable microscope and a computer vision algorithm developed in MATLAB. The results showed that the stability of the RFC process was dependent on the work and the travel angle. It was also seen that a coherent region of stable incident angles could be found. All experiments were conducted with a 3 kW single mode fiber laser at the laser processing laboratory at Aalborg University.

  6. Ensuring flat cuts in longwall mining

    NASA Technical Reports Server (NTRS)

    Campbell, R. A.; Currie, J. R.; Deaton, E. T.; Kissel, R. R.

    1979-01-01

    Minicomputer-controlled towed vehicle automatically determines flatness of wall of coal or other mineral as it is being cut by mining machine and allows machine operator to correct cut as necessary. Vehicle is used for longwall mining.

  7. Aqueous cutting fluid for machining fissionable materials

    SciTech Connect

    Duerksen, Walter K.; Googin, John M.; Napier, Jr., Bradley

    1984-01-01

    The present invention is directed to a cutting fluid for machining fissionable material. The cutting fluid is formed of glycol, water and boron compound in an adequate concentration for effective neutron attenuation so as to inhibit criticality incidents during machining.

  8. Anisotropy in Alpedrete granite cutting (Rift, Grain and Hardway directions) and effect on bush hammered heritage ashlars

    NASA Astrophysics Data System (ADS)

    Freire-Lista, David Martin; Fort, Rafael

    2015-04-01

    Many monuments and cities that are part of humanity's heritage have been built with carved granite ashlars. This dimension stone is one of the most used due to its abundance and durability. Traditional quarrymen have used anisotropic planes to cut granite blocks in the quarry for improved cutting performance. These planes are called Rift, Grain and Hardway (R, G, H) according to the ease of cutting. The aim of this study is to determine the response of each of the three orthogonal cutting planes R, G and H to the craft styling with bush hammer, based on their decay. Alpedrete granite was selected for this research, it is a monzogranite quarried in the Sierra de Guadarrana (Spanish Central System) foothills, in the province of Madrid, Spain. It is one of the most representative of Madrid's heritage granites. Alpedrete granite is also used as building stone in other European cities. From an Alpedrete granite bush hammered ashlar, three thin sections were cut parallel to the H plane; these thin sections cut R and G bush hammered planes. Also three thin sections have been cut parallel to the R plane at a distance of 2 mm, 10 mm and 30 mm from the bush hammered surface. All thin sections have been treated with fluorescein. In each of the thin sections a micrograph mosaic was performed covering the entire area (about 10 cm2, 300 photomicrographs) and printed with 120 increases. The length and spacing of inter-, intra- and trans-crystalline microcracks were quantified and measured. Microcracks were subdivided based on affected minerals in each R, G and H planes. Through these observations it was found that Alpedrete Granite R plane (easier to cut) is determined by exfoliation microcracks orientation. That is, R plane is parallel to the exfoliations microcracks, which are intra-crystalline and straight. The cutting of stones in the R plane is due to the coalescence of straight microcracks in the plane. This plane minimizes the effort and cost of subsequent carving so it

  9. An Automated Approach for Slicing Plane Placement in Visual Data Analysis.

    PubMed

    Obermaier, Harald; Joy, Kenneth I

    2015-12-01

    Effective display and visual analysis of complex 3D data is a challenging task. Occlusions, overlaps, and projective distortions-as frequently caused by typical 3D rendering techniques-can be major obstacles to unambiguous and robust data analysis. Slicing planes are a ubiquitous tool to resolve several of these issues. They act as simple clipping geometry to provide clear cut-away views of the data. We propose to enhance the visualization and analysis process by providing methods for automatic placement of such slicing planes based on local optimization of gradient vector flow. The final obtained slicing planes maximize the total amount of information displayed with respect to a pre-specified importance function. We demonstrate how such automated slicing plane placement is able to support and enrich 3D data visualization and analysis in multiple scenarios, such as volume or surface rendering, and evaluate its performance in several benchmark data sets. PMID:26529461

  10. 27 CFR 6.92 - Newspaper cuts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers'...

  11. 27 CFR 6.92 - Newspaper cuts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers'...

  12. 27 CFR 6.92 - Newspaper cuts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers'...

  13. 27 CFR 6.92 - Newspaper cuts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers'...

  14. Teaching Budget Cuts to Third Graders

    ERIC Educational Resources Information Center

    Weiss, Dale

    2011-01-01

    As a teacher in the Milwaukee Public Schools (MPS) for the past 16 years, this author has grown used to dismal budget cut news arriving each February. Although cuts are always frustrating and their results burdensome, his school has been able to "hang on" reasonably well. This year, however, the budget cuts were extreme. The school's budget was…

  15. Cutting Tool For Shaving Weld Beads

    NASA Technical Reports Server (NTRS)

    Hoffman, David S.; Mcferrin, David C.; Daniel, Ronald L., Jr.; Coby, John B., Jr.; Dawson, Sidney G.

    1995-01-01

    Cutting tool proposed for use in shaving weld beads flush with adjacent surfaces of weldments. Modified version of commercial pneumatically driven rotary cutting tool, cutting wheel of which turns at speeds sufficient for machining nickel alloys, titanium, and stainless steels. Equipped with forward-mounted handle and rear-mounted skid plate to maximize control and reduce dependence on skill of technician.

  16. 27 CFR 6.92 - Newspaper cuts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or engraved blocks for use in retailers'...

  17. Cutting a Tapered Edge on Padding Material

    NASA Technical Reports Server (NTRS)

    Mitchell, M. J.

    1982-01-01

    Resilience and flexibility of felt, rubber, or other padding materials allow them to be clamped in form block, cut straight down, and then released to produce straight clean tapered edge. With material held in slanted position, edge can be cut straight down; hence cut depth is minimum.

  18. SNAP Satellite Focal Plane Development

    SciTech Connect

    Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C.; Barrelet, E.; Basa, S.; Bercovitz, J.; Bergstrom, L.; Berstein, G.P.; Bester, M.; Bohlin, R.; Bonissent, A.; Bower, C.; Campbell, M.; Carithers, W.; Commins, E.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, A.; Ellis, R.; Emmett, W.; Eriksson, M.; Fouchez,D.; Fruchter, A.; Genat, J-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Heetderks, H.; Holland, S.; Huterer, D.; Johnson, W.; Kadel, R.; Karcher,A.; Kim, A.; Kolbe, W.; Lafever, R.; Lamoureaux, J.; Lampton, M.; Lefevre, O.; Levi, M.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Mazure, A.; McKay, T.; McKee, S.; Miquel, R.; Morgan, N.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Roe, N.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Prieto, E.; Rabinowitz,D.; Refregier, A.; Rhodes, J.; Schubnell, M.; Sholl, M.; Smadja, G.; Smith, R.; Smoot, G.; Snyder, J.; Spadafora, A.; Szymkowiak, A.; Tarle,G.; Taylor, K.; Tilquin, A.; Tomasch, A.; Vincent, D.; von der Lippe, H.; Walder, J-P.; Wang, G.

    2003-07-07

    The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics.

  19. National Aero-Space Plane

    NASA Technical Reports Server (NTRS)

    Piland, William M.

    1987-01-01

    An account is given of the technology development management objectives thus far planned for the DOD/NASA National Aero-Space Plane (NASP). The technology required by NASP will first be developed in ground-based facilities and then integrated during the design and construction of the X-30 experimental aircraft. Five airframe and three powerplant manufacturers are currently engaged in an 18-month effort encompassing design studies and tradeoff analyses. The first flight of the X-30 is scheduled for early 1993.

  20. Haplotyping algorithms

    SciTech Connect

    Sobel, E.; Lange, K.; O`Connell, J.R.

    1996-12-31

    Haplotyping is the logical process of inferring gene flow in a pedigree based on phenotyping results at a small number of genetic loci. This paper formalizes the haplotyping problem and suggests four algorithms for haplotype reconstruction. These algorithms range from exhaustive enumeration of all haplotype vectors to combinatorial optimization by simulated annealing. Application of the algorithms to published genetic analyses shows that manual haplotyping is often erroneous. Haplotyping is employed in screening pedigrees for phenotyping errors and in positional cloning of disease genes from conserved haplotypes in population isolates. 26 refs., 6 figs., 3 tabs.

  1. Anti-plane transverse waves propagation in nanoscale periodic layered piezoelectric structures.

    PubMed

    Chen, A-Li; Yan, Dong-Jia; Wang, Yue-Sheng; Zhang, Chuanzeng

    2016-02-01

    In this paper, anti-plane transverse wave propagation in nanoscale periodic layered piezoelectric structures is studied. The localization factor is introduced to characterize the wave propagation behavior. The transfer matrix method based on the nonlocal piezoelectricity continuum theory is used to calculate the localization factor. Additionally, the stiffness matrix method is applied to compute the wave transmission spectra. A cut-off frequency is found, beyond which the elastic waves cannot propagate through the periodic structure. The size effect or the influence of the ratio of the internal to external characteristic lengths on the cut-off frequency and the wave propagation behavior are investigated and discussed. PMID:26518526

  2. Algorithmic advances in stochastic programming

    SciTech Connect

    Morton, D.P.

    1993-07-01

    Practical planning problems with deterministic forecasts of inherently uncertain parameters often yield unsatisfactory solutions. Stochastic programming formulations allow uncertain parameters to be modeled as random variables with known distributions, but the size of the resulting mathematical programs can be formidable. Decomposition-based algorithms take advantage of special structure and provide an attractive approach to such problems. We consider two classes of decomposition-based stochastic programming algorithms. The first type of algorithm addresses problems with a ``manageable`` number of scenarios. The second class incorporates Monte Carlo sampling within a decomposition algorithm. We develop and empirically study an enhanced Benders decomposition algorithm for solving multistage stochastic linear programs within a prespecified tolerance. The enhancements include warm start basis selection, preliminary cut generation, the multicut procedure, and decision tree traversing strategies. Computational results are presented for a collection of ``real-world`` multistage stochastic hydroelectric scheduling problems. Recently, there has been an increased focus on decomposition-based algorithms that use sampling within the optimization framework. These approaches hold much promise for solving stochastic programs with many scenarios. A critical component of such algorithms is a stopping criterion to ensure the quality of the solution. With this as motivation, we develop a stopping rule theory for algorithms in which bounds on the optimal objective function value are estimated by sampling. Rules are provided for selecting sample sizes and terminating the algorithm under which asymptotic validity of confidence interval statements for the quality of the proposed solution can be verified. Issues associated with the application of this theory to two sampling-based algorithms are considered, and preliminary empirical coverage results are presented.

  3. Estimation of vocal fold plane in 3D CT images for diagnosis of vocal fold abnormalities.

    PubMed

    Hewavitharanage, Sajini; Gubbi, Jayavardhana; Thyagarajan, Dominic; Lau, Ken; Palaniswami, Marimuthu

    2015-01-01

    Vocal folds are the key body structures that are responsible for phonation and regulating air movement into and out of lungs. Various vocal fold disorders may seriously impact the quality of life. When diagnosing vocal fold disorders, CT of the neck is the commonly used imaging method. However, vocal folds do not align with the normal axial plane of a neck and the plane containing vocal cords and arytenoids does vary during phonation. It is therefore important to generate an algorithm for detecting the actual plane containing vocal folds. In this paper, we propose a method to automatically estimate the vocal fold plane using vertebral column and anterior commissure localization. Gray-level thresholding, connected component analysis, rule based segmentation and unsupervised k-means clustering were used in the proposed algorithm. The anterior commissure segmentation method achieved an accuracy of 85%, a good estimate of the expert assessment. PMID:26736949

  4. a Multi-View Image Matching Method for Feature Points Based on the Moving Z-Plane Constraint

    NASA Astrophysics Data System (ADS)

    Wang, J.; Song, W.; Bu, F.

    2012-07-01

    Focusing on the serious occlusion problem in city images, this paper makes full use of the advantage of multi-view image matching, and proposes a reliable multi-view image matching method based on the moving Z-Plane constraint. It supposes a fictitious plane in the object space, and the plane is divided to regular grid cell (small plane element) by a certain interval (≥ image resolution). By moving the plane to different elevation positions, this algorithm makes feature point projection ray in overall images intersect with the plane, and constrains the candidate points by grid cells in the plane. Feature points which come from different images projection ray in the same grid cell on the plane may be regarded as the matching candidates. It selects the images which matching candidate points by gray similarity constraint to avoid the effect from occlusion image. According to the number of projection ray in the grid cell, this algorithm adopts hierarchy matching strategy of "the best candidate will be matched in the first instant", and uses initial matching results as constraint condition in the latter matching process. Finally, the validity of the algorithm proposed in this paper is verified by the experiments using four UltraCamX (UCX) digital aerial images and the algorithm is shown to have reliable matching results.

  5. Rewritable photochromic focal plane masks

    NASA Astrophysics Data System (ADS)

    Molinari, Emilio; Bertarelli, Chiara; Bianco, Andrea; Bortoletto, Fabio; Conconi, Paolo; Crimi, Giuseppe; Gallazzi, Maria C.; Giro, Enrico; Lucotti, Andrea; Pernechele, Claudio; Zerbi, Filippo M.; Zerbi, Giuseppe

    2003-02-01

    The application of organic photochromic materials in astronomy is opening new possibilities which we are investigating in order to design innovative devices for future instrumentation. The photochromic property of transparent/opaque transition (although in a limited wavelength range) and the changes in intrinsic refractive index have led our studies to application in astronomic spectrographs, both as focal plane mask (for MOS application) and as dispersive elements (volume phase holographic gratings, VPHG), respectively. In both cases the possibility to write and erase devices with suitable irradiation has revealed a new perspective for non-disposable and fully customizable items for spectroscopy. Pursuing this goal we have synthesized a series of novel photochromic materials belonging to the diarylethenes. They fulfill the requirements of thermal stability and fatigue resistance necessary to build functional devices. Prototypes of high contrast focal plane mask working in the H-alpha spectral region have been manufactured and characterized both in laboratory and with the AFOSC camera at Asiago telescope (1.8 m). A custom writing robot (ARATRO) which, taking imaging frames and with the aid of interactive mask design software and ad hoc control electronics, is able to write MOS masks, has been constructed. The design of the MOS masks allow the fitting in the AFOSC slit wheel. The overall set-up is ready for the sky tests.

  6. The Bolocam Galactic Plane Survey

    NASA Technical Reports Server (NTRS)

    Glenn, Jason; Aguirre, James; Bally, John; Battersby, Cara; Bradley, Eric Todd; Cyganowski, Claudia; Dowell, Darren; Drosback, Meredith; Dunham, Miranda K.; Evans, Neal J., II; Ginsburg, Adam; Harvey, Paul; Rosolowsky, Erik; Schlingman, Wayne; Shirley, Yancy L.; Stringfellow, Guy S.; Walawender, Josh; Williams, Jonathan

    2009-01-01

    The Bolocam Galactic Plane Survey (BGPS) is a 1.1 millimeter continuum survey of the northern Galactic Plane made with Bolocam and the Caltech Submillimeter Observatory. The coverage totals 170 square degrees, comprised of a contiguous range from -10.5 deg is less than or equal to 90.5 deg, 0.5 deg is less than or equal to b is less than or equal to 0.5 deg, with extended coverage in b in selected regions, and four targeted regions in the outer Galaxy, including: IC1396, toward the Perseus arm at l is approximately 111 deg, W3/4/5, and Gem OB1. Depths of the maps range from 30 to 60 mJy beam (sup 1). Approximately 8,400 sources were detected and the maps and source catalog have been made publicly available. Millimeter-wave thermal dust emission reveals dense regions within molecular clouds, thus the BGPS serves as a database for studies of the dense interstellar medium and star formation within the Milky Way.

  7. Automated Laser Cutting In Three Dimensions

    NASA Technical Reports Server (NTRS)

    Bird, Lisa T.; Yvanovich, Mark A.; Angell, Terry R.; Bishop, Patricia J.; Dai, Weimin; Dobbs, Robert D.; He, Mingli; Minardi, Antonio; Shelton, Bret A.

    1995-01-01

    Computer-controlled machine-tool system uses laser beam assisted by directed flow of air to cut refractory materials into complex three-dimensional shapes. Velocity, position, and angle of cut varied. In original application, materials in question were thermally insulating thick blankets and tiles used on space shuttle. System shapes tile to concave or convex contours and cuts beveled edges on blanket, without cutting through outer layer of quartz fabric part of blanket. For safety, system entirely enclosed to prevent escape of laser energy. No dust generated during cutting operation - all material vaporized; larger solid chips dislodged from workpiece easily removed later.

  8. Laser Cutting of Carbon Fiber Fabrics

    NASA Astrophysics Data System (ADS)

    Fuchs, A. N.; Schoeberl, M.; Tremmer, J.; Zaeh, M. F.

    Due to their high weight-specific mechanical stiffness and strength, parts made from carbon fiber reinforced polymers (CFRP) are increasingly used as structural components in the aircraft and automotive industry. However, the cutting of preforms, as with most automated manufacturing processes for CFRP components, has not yet been fully optimized. This paper discusses laser cutting, an alternative method to the mechanical cutting of preforms. Experiments with remote laser cutting and gas assisted laser cutting were carried out in order to identify achievable machining speeds. The advantages of the two different processes as well as their fitness for use in mass production are discussed.

  9. Near-infrared optical imaging of human brain based on the semi-3D reconstruction algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Meng, Wei; Qin, Zhuanping; Zhou, Xiaoqing; Zhao, Huijuan; Gao, Feng

    2013-03-01

    In the non-invasive brain imaging with near-infrared light, precise head model is of great significance to the forward model and the image reconstruction. To deal with the individual difference of human head tissues and the problem of the irregular curvature, in this paper, we extracted head structure with Mimics software from the MRI image of a volunteer. This scheme makes it possible to assign the optical parameters to every layer of the head tissues reasonably and solve the diffusion equation with the finite-element analysis. During the solution of the inverse problem, a semi-3D reconstruction algorithm is adopted to trade off the computation cost and accuracy between the full 3-D and the 2-D reconstructions. In this scheme, the changes in the optical properties of the inclusions are assumed either axially invariable or confined to the imaging plane, while the 3-D nature of the photon migration is still retained. This therefore leads to a 2-D inverse issue with the matched 3-D forward model. Simulation results show that comparing to the 3-D reconstruction algorithm, the Semi-3D reconstruction algorithm cut 27% the calculation time consumption.

  10. Cutting of bent vortex lines

    SciTech Connect

    Wagenleithner, P.

    1982-07-01

    One of the major problems in the application of type II superconductors is the appearance of resistivity in case where a current-carrying specimen is in a longitudinal magnetic field. This is explained by the onset of flux-line cutting events, followed by cross-joining of the line parts. The calculation given here shows the amount of repulsive force and energy between two curved vortex lines and examines the general stability of the vortex-vortex system. First, the actual interaction potential between curved vortices is computed. It includes all electromagnetic and core overlap terms of interactions and self-interaction, and allows computation of the system energy under all curved vortex-line configurations. A computer program is used to find the form of lowest free energy. To do this, special trial functions are established to describe the three-dimensional form of the vortex-vortex system. In these functions parameters determine the qualitative and quantitative form. The asymptotic boundary conditions are built into the nature of the trial functions. The computer program now minimizes the free energy with respect to these parameters. The resulting repulsive energy and force are more than ten times less than the known results for straight flux lines, especially for small asymptotic cutting angles. There is no sharp maximum in the plot of repulsive force versus flux-line separation. A remarkable results is the loss of general stability below a separation distance of several London penetration depths, depending on the cutting angle and the Ginzburg-Landau parameter. The explanation lies in the local attraction of central sections of the vortices as a result of configurational adaption. This explains the onset of resistance at small currents and small magnetic fields.

  11. Cutting costs without drawing blood.

    PubMed

    Copeland, T

    2000-01-01

    When looking for ways to cut costs, most managers reach for the head-count hatchet, and the markets usually roar with approval. But a company can almost always create far more sustainable value by rigorously evaluating the small-ticket capital items that often get rubber-stamped. Drawing on his experience as a consultant and providing numerous anecdotes, the author contends that those "little" requests often prove to be gold plated or unnecessary. A disciplined evaluation involves asking only eight questions and conducting postmortems--regular audits of units' capital spending. But the payoff is enormous. Because cutting the capital budget increases cash flow, the author argues that a permanent cut of just 15% in the planned level of capital spending could boost some companies' market capitalization by as much as 30%. The first three questions--Is this your investment to make? Does it really have to be new? How are our competitors meeting compliance needs?--are asked of operating managers as they assemble capital project requests. The next three are asked by senior managers of themselves and their colleagues as they examine proposals: Is the left hand duplicating investments made by the right? Are trade-offs between profit and capital spending well understood? Are there signs of budget massage? At the end of the review process, senior managers ask: Are we fully using shared assets? How fine-grained are our capacity measures? The author's suggestions for the postmortem include searching for systematic problems with whole classes of expenditures and making sure audit teams come up with specific recommendations for change. PMID:11143151

  12. Free-piston cutting machine

    DOEpatents

    Ciccarelli, Gaby; Subudhi, Manomohan; Hall, Robert E.

    2000-01-01

    A cutting machine includes a gun barrel for receiving a projectile. A compression tube is disposed in flow communication with the barrel and includes a piston therein. A reservoir is disposed in flow communication with the tube and receives a first gas under pressure. A second gas fills the compression tube on a front face of the piston. And, the pressurized first gas is discharged into the tube on a back face of the piston to accelerate the piston through the tube for compressing the second gas, and in turn launching the projectile through the barrel to impact a workpiece.

  13. Cutting, Splicing, and Kelvin Waves

    NASA Astrophysics Data System (ADS)

    Scheeler, Martin; Kleckner, Dustin; Irvine, William T. M.

    2013-11-01

    Recent experimental advances have allowed us to create, visualize and track vortices of prescribed shape and topology in classical fluids. We study the effect of surgery (cutting and splicing) on the evolution of the geometry and topology of these vortex loops, with a particular focus on the wave-like excitations generated by these operations. We interpret the dynamics of these excitations and the role they play within the broader context of vortex evolution. This work was supported by the National Science Foundation Materials Research and Engineering Centers (MRSEC) Program at the University of Chicago (DMR-0820054) and the Packard Foundation through a Packard fellowship.

  14. Cutting Properties and Wearing Process of Diamond Film Coated Tools in the Dry-Cutting

    NASA Astrophysics Data System (ADS)

    Zhong, Qimao

    Dry cutting can eliminate a series of negative effects of coolant. Based on tribology principle of coated tool, diamond film coated tool is used to cut the same workpiece under the conditions of dry-cutting and coolant. The tool's cutting properties and wear mechanism are studied by tests. Results imply that this coated tool will be applied more widely day by day in the dry-cutting.

  15. Thermal lensing in diode-pumped [001]-cut tetragonal crystals

    NASA Astrophysics Data System (ADS)

    Yumashev, Konstantin; Loiko, Pavel

    2015-11-01

    Thermal lensing is theoretically studied for laser discs from [001]-cut tetragonal crystals under the plane stress approximation, considering anisotropy of their elastic and photo-elastic properties. Analytical description of the stress-induced birefringence is presented. This allows us to derive analytical expressions for the photo-elastic term χ″, "generalized" thermo-optic coefficient (TOC), sensitivity factors of the thermal lens and its astigmatism degree, as well as discuss orientation of the principal meridional planes of the lens. These parameters are determined for the discs from tetragonal scheelite-type molydbate crystals, Nd:PbMoO4, Nd:CaMoO4 and Nd:NaBi(MoO4)2 at ~1 μm. It is shown that the photo-elastic effect plays an important role in the formation of the thermal lens for tetragonal crystals, and χ″ value can be either positive or negative. We also predict theoretically that for anisotropic crystals the orientation of the principal meridional planes of the thermal lens is not linked to the polarization direction.

  16. Resolution improvements in integral microscopy with Fourier plane recording.

    PubMed

    Llavador, A; Sola-Pikabea, J; Saavedra, G; Javidi, B; Martínez-Corral, M

    2016-09-01

    Integral microscopes (IMic) have been recently developed in order to capture the spatial and the angular information of 3D microscopic samples with a single exposure. Computational post-processing of this information permits to carry out a 3D reconstruction of the sample. By applying conventional algorithms, both depth and also view reconstructions are possible. However, the main drawback of IMic is that the resolution of the reconstructed images is low and axially heterogeneous. In this paper, we propose a new configuration of the IMic by placing the lens array not at the image plane, but at the pupil (or Fourier) plane of the microscope objective. With this novel system, the spatial resolution is increased by factor 1.4, and the depth of field is substantially enlarged. Our experiments show the feasibility of the proposed method. PMID:27607682

  17. Optimal focal-plane restoration

    NASA Technical Reports Server (NTRS)

    Reichenbach, Stephen E.; Park, Stephen K.

    1989-01-01

    Image restoration can be implemented efficiently by calculating the convolution of the digital image and a small kernel during image acquisition. Processing the image in the focal-plane in this way requires less computation than traditional Fourier-transform-based techniques such as the Wiener filter and constrained least-squares filter. Here, the values of the convolution kernel that yield the restoration with minimum expected mean-square error are determined using a frequency analysis of the end-to-end imaging system. This development accounts for constraints on the size and shape of the spatial kernel and all the components of the imaging system. Simulation results indicate the technique is effective and efficient.

  18. Broken chiral symmetry on a null plane

    SciTech Connect

    Beane, Silas R.

    2013-10-15

    On a null-plane (light-front), all effects of spontaneous chiral symmetry breaking are contained in the three Hamiltonians (dynamical Poincaré generators), while the vacuum state is a chiral invariant. This property is used to give a general proof of Goldstone’s theorem on a null-plane. Focusing on null-plane QCD with N degenerate flavors of light quarks, the chiral-symmetry breaking Hamiltonians are obtained, and the role of vacuum condensates is clarified. In particular, the null-plane Gell-Mann–Oakes–Renner formula is derived, and a general prescription is given for mapping all chiral-symmetry breaking QCD condensates to chiral-symmetry conserving null-plane QCD condensates. The utility of the null-plane description lies in the operator algebra that mixes the null-plane Hamiltonians and the chiral symmetry charges. It is demonstrated that in a certain non-trivial limit, the null-plane operator algebra reduces to the symmetry group SU(2N) of the constituent quark model. -- Highlights: •A proof (the first) of Goldstone’s theorem on a null-plane is given. •The puzzle of chiral-symmetry breaking condensates on a null-plane is solved. •The emergence of spin-flavor symmetries in null-plane QCD is demonstrated.

  19. Mechanism for control plane authentication

    SciTech Connect

    Tarman, T.D.

    1996-06-01

    The purpose of this contribution is to propose an ``Authentication Information Element`` that can be used to carry authentication information within the ATM signaling protocols. This information may be used by either signaling entity to validate the claimed identity of the other, and to verify the integrity of a portion of a message`s contents. By specifying a generic authentication IE, authentication information can be generated by any signature algorithm, and can be appended to any ATM signaling message. Procedures for the use of this information element are also provided.

  20. Multiple Plane Phase Retrieval Based On Inverse Regularized Imaging and Discrete Diffraction Transform

    NASA Astrophysics Data System (ADS)

    Migukin, Artem; Katkovnik, Vladimir; Astola, Jaakko

    2010-04-01

    The phase retrieval is formulated as an inverse problem, where the forward propagation is defined by Discrete Diffraction Transform (DDT) [1], [2]. This propagation model is precise and aliasing free for pixelwise invariant (pixelated) wave field distributions in the sensor and object planes. Because of finite size of sensors DDT can be ill-conditioned and the regularization is an important component of the inverse. The proposed algorithm is designed for multiple plane observations and can be treated as a generalization of the Gerchberg-Saxton iterative algorithm. The proposed algorithm is studied by numerical experiments produced for phase and amplitude modulated object distributions. Comparison versus the conventional forward propagation models such as the angular spectrum decomposition and the convolutional model used in the algorithm of the same structure shows a clear advantage of DDT enabling better accuracy and better imaging.

  1. Unsupervised color image segmentation using graph cuts with multi-components

    NASA Astrophysics Data System (ADS)

    Li, Lei; Jin, Lianghai; Song, Enmin; Dong, Zhuoli

    2013-10-01

    A novel unsupervised color image segmentation method based on graph cuts with multi-components is proposed, which finds an optimal segmentation of an image by regarding it as an energy minimization problem. First, L*a*b* color space is chosen as color feature, and the multi-scale quaternion Gabor filter is employed to extract texture feature of the given image. Then, the segmentation is formulated in terms of energy minimization with an iterative process based on graph cuts, and the connected regions in each segment are considered as the components of the segment in each iteration. In addition, canny edge detector combined with color gradient is used to remove weak edges in segmentation results with the proposed algorithm. In contrast to previous algorithms, our method could greatly reduce computational complexity during inference procedure by graph cuts. Experimental results demonstrate the promising performance of the proposed method.

  2. Compact Focal Plane Assembly for Planetary Science

    NASA Technical Reports Server (NTRS)

    Brown, Ari; Aslam, Shahid; Huang, Wei-Chung; Steptoe-Jackson, Rosalind

    2013-01-01

    A compact radiometric focal plane assembly (FPA) has been designed in which the filters are individually co-registered over compact thermopile pixels. This allows for construction of an ultralightweight and compact radiometric instrument. The FPA also incorporates micromachined baffles in order to mitigate crosstalk and low-pass filter windows in order to eliminate high-frequency radiation. Compact metal mesh bandpass filters were fabricated for the far infrared (FIR) spectral range (17 to 100 microns), a game-changing technology for future planetary FIR instruments. This fabrication approach allows the dimensions of individual metal mesh filters to be tailored with better than 10- micron precision. In contrast, conventional compact filters employed in recent missions and in near-term instruments consist of large filter sheets manually cut into much smaller pieces, which is a much less precise and much more labor-intensive, expensive, and difficult process. Filter performance was validated by integrating them with thermopile arrays. Demonstration of the FPA will require the integration of two technologies. The first technology is compact, lightweight, robust against cryogenic thermal cycling, and radiation-hard micromachined bandpass filters. They consist of a copper mesh supported on a deep reactive ion-etched silicon frame. This design architecture is advantageous when constructing a lightweight and compact instrument because (1) the frame acts like a jig and facilitates filter integration with the FPA, (2) the frame can be designed so as to maximize the FPA field of view, (3) the frame can be simultaneously used as a baffle for mitigating crosstalk, and (4) micron-scale alignment features can be patterned so as to permit high-precision filter stacking and, consequently, increase the filter bandwidth and sharpen the out-of-band rolloff. The second technology consists of leveraging, from another project, compact and lightweight Bi0.87Sb0.13/Sb arrayed thermopiles

  3. Cut performance levels and testing.

    PubMed

    Bennett, Bill; Moreland, Jeff

    2011-11-01

    While the ISEA performance levels and general recommendations detailed above can help tp provide guidance when selecting hand protection products, the responsibility for testing products for specific end-user applications still rests with the end user. We can indicate, for example, that a medium-weight, uncoated Kevlar glove will typically have an ISEA cut rating of 3, but we cannot say the glove will provide the level of protection needed for the range of jobs on an automobile assembly line. Another Level 3 glove might be better suited to an application the require the worker to have an oil grip. As glove manufacturers, we know gloves. We do not know the details about every workplace. We therefore, must look to our customers to provide us the properties they need for hand protection products that will sufficiently protect their workers on the job. PMID:22135955

  4. The UKIDSS Galactic Plane Survey

    NASA Astrophysics Data System (ADS)

    Lucas, P. W.; Hoare, M. G.; Longmore, A.; Schröder, A. C.; Davis, C. J.; Adamson, A.; Bandyopadhyay, R. M.; de Grijs, R.; Smith, M.; Gosling, A.; Mitchison, S.; Gáspár, A.; Coe, M.; Tamura, M.; Parker, Q.; Irwin, M.; Hambly, N.; Bryant, J.; Collins, R. S.; Cross, N.; Evans, D. W.; Gonzalez-Solares, E.; Hodgkin, S.; Lewis, J.; Read, M.; Riello, M.; Sutorius, E. T. W.; Lawrence, A.; Drew, J. E.; Dye, S.; Thompson, M. A.

    2008-11-01

    The UKIDSS Galactic Plane Survey (GPS) is one of the five near-infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared Telescope. It is surveying 1868 deg2 of the northern and equatorial Galactic plane at Galactic latitudes -5° < b < 5° in the J, H and K filters and a ~200-deg2 area of the Taurus-Auriga-Perseus molecular cloud complex in these three filters and the 2.12 μm (1-0) H2 filter. It will provide data on ~2 × 109 sources. Here we describe the properties of the data set and provide a user's guide for its exploitation. We also present brief Demonstration Science results from DR2 and from the Science Verification programme. These results illustrate how GPS data will frequently be combined with data taken in other wavebands to produce scientific results. The Demonstration Science comprises six studies. (1) A GPS-Spitzer-GLIMPSE cross-match for the star formation region G28.983-0.603 to identify YSOs. This increases the number of YSOs identified by a factor of 10 compared to GLIMPSE alone. (2) A wide-field study of the M17 nebula, in which an extinction map of the field is presented and the effect of source confusion on luminosity functions in different subregions is noted. (3) H2 emission in the ρ Ophiuchi dark cloud. All the molecular jets are traced back to a single active clump containing only a few protostars, which suggests that the duration of strong jet activity and associated rapid accretion in low-mass protostars is brief. (4) X-ray sources in the nuclear bulge. The GPS data distinguishes local main-sequence counterparts with soft X-ray spectra from nuclear bulge giant counterparts with hard X-ray spectra. (5) External galaxies in the zone of avoidance. The galaxies are clearly distinguished from stars in fields at longitudes l > 90°. (6) IPHAS-GPS optical-infrared spectrophotometric typing. The (i' - J) versus (J - H) diagram is used to distinguish A-F type

  5. Out-of-plane properties

    NASA Technical Reports Server (NTRS)

    Jackson, Wade C.; Portanova, Marc A.

    1995-01-01

    This paper summarizes three areas of research which were performed to characterize out-of-plane properties of composite materials. In the first investigation, a series of tests was run to characterize the through-the-thickness tensile strength for a variety of composites that included 2D braids, 2D and 3D weaves, and prepreg tapes. A new test method based on a curved beam was evaluated. Failures were significantly different between the 2D materials and the 3D weaves. The 2D materials delaminated between layers due to out-of-plane tensile stresses while the 3D weaves failed due to the formation of radial cracks between the surface plies caused by high circumferential stresses along the inner radius. The strength of the 2D textile composites did not increase relative to the tapes. Final failure in the 3D weaves was caused by a circumferential crack similar to the 2D materials and occurred at a lower bending moment than in other materials. The early failures in the 3D weaves were caused by radial crack formation rather than a low through-the-thickness strength. The second investigation focused on the development of a standard impact test method to measure impact damage resistance. The only impact tests that currently exist are compression after impact (CAI) tests which incorporate elements of both damage resistance and damage tolerance. A new impact test method is under development which uses a quasi-static indentation (QSI) test to directly measure damage resistance. Damage resistance is quantified in terms of the contact force to produce a unit of damage where a metric for damage may be area in C-scan, depth of residual dent , penetration, damage growth, etc. A final draft of an impact standard that uses a QSI test method will be presented to the ASTM Impact Task Group on impact. In the third investigation, the impact damage resistance behavior of a variety of textile materials was studied using the QSI test method. In this study, the force where large damage

  6. Theoretical aspects of fibre laser cutting

    NASA Astrophysics Data System (ADS)

    Mahrle, A.; Beyer, E.

    2009-09-01

    Fibre lasers offer distinct advantages over established laser systems with respect to power efficiency, beam guidance and beam quality. Consequently, the potential of these new laser beam sources will be increasingly exploited for laser cutting applications that are conventionally carried out with CO2 lasers. However, theoretical estimates of the effective absorptivity at the cut front suggest that the shorter wavelength of the fibre laser in combination with its high focusability seems to be primarily advantageous for thin sheet metal cutting whereas the CO2 laser is probably still capable of cutting thicker materials more efficiently. This surprising result is a consequence of the absorptivity behaviour of metals that shows essential quantitative differences for the corresponding wavelengths of both laser sources as a function of the angle of incidence between the laser beam and the material to be cut. In evaluation of the revealed dependences, solution strategies for an improvement of the efficiency of fibre laser cutting of thicker metal sheets are suggested.

  7. An application of three-dimensional modeling in the cutting machine of intersecting line software

    NASA Astrophysics Data System (ADS)

    Lu, Jixiang

    2011-11-01

    This paper developed a software platform of intersecting line cutting machine. The software platform consists of three parts. The first is the interface of parameter input and modify, the second is the three-dimensional display of main tube and branch tube, and the last is the cutting simulation and G code output. We can obtain intersection data by intersection algorithm, and we also make three-dimensional model and dynamic simulation on the data of intersecting line cutting. By changing the parameters and the assembly sequence of main tube and branch tube, you can see the modified two-dimensional and three-dimensional graphics and corresponding G-code output file. This method has been applied to practical cutting machine of intersecting line software.

  8. Computer-aided design of millimeter-wave E-plane filters

    NASA Astrophysics Data System (ADS)

    Shih, Y.-C.; Itoh, T.; Bui, L. Q.

    1983-02-01

    A computer-aided design (CAD) algorithm has been developed for a class of E-plane bandpass filters. The analysis portion of the algorithm is based on the residue-calculus technique and a generalized scattering parameter method. It is mathematically exact and numerically very efficient. Filters designed with this method have been fabricated and tested in Ka-band. Good agreement with design has been obtained.

  9. Erbium localized doping into various cuts of lithium niobate and sapphire: a comparative study

    NASA Astrophysics Data System (ADS)

    Nekvindova, Pavla; Mackova, Anna; Perina, Vratislav; Cervena, Jarmila; Capek, Pavel; Schroefel, Josef; Spirkova, Jarmila; Oswald, Jiri

    2003-07-01

    Medium temperature (350 °C) localized doping of Er3+ was studied in lithium niobate (LN) and sapphire single crystal wafers that were cut in various crystallographic directions. It was found that the efficiency of the doping was connected with orientations of the substrate wafers of both LN and sapphire, and with the presence of mobile lithium ions in the structure of LN. The basic interstitial mechanism of erbium incorporation into the structure of sapphire and LN is in the latter accompanied with erbium for lithium ion exchange. While the rate of the interstitial diffusion was higher in the wafers oriented perpendicularly towards the cleavage planes of the crystals, ion exchange process was significant in the wafers cut in cleavage planes. Waveguiding properties in erbium doped lithium niobate originated rather from presence of erbium in the structure of the crystals than being a consequence of a weak proton exchange. Luminescence properties of the fabricated samples are also presented.

  10. Algorithm development

    NASA Technical Reports Server (NTRS)

    Barth, Timothy J.; Lomax, Harvard

    1987-01-01

    The past decade has seen considerable activity in algorithm development for the Navier-Stokes equations. This has resulted in a wide variety of useful new techniques. Some examples for the numerical solution of the Navier-Stokes equations are presented, divided into two parts. One is devoted to the incompressible Navier-Stokes equations, and the other to the compressible form.

  11. Is soccer kick performance better after a "faking" (cutting) maneuver task?

    PubMed

    Katis, Athanasios; Kellis, Eleftherios

    2011-03-01

    Cutting in soccer is a common skill used to avoid the opponent's pressure but the potential effects of such a skill on instep kicking performance have not been previously investigated. The purpose of this study was to examine the differences in lower limb biomechanics between straight approach soccer kicks and kicks performed following a cutting maneuver task. Ten young amateur soccer players performed, in a random order, instep kicks after a two-step straight approach run and kicks after a double "faking" cutting maneuver task. The results showed that kicking after a cutting maneuver task displayed significantly lower ball speed values compared with the straight approach instep kicking (16.73 vs. 19.78 m/s, respectively; p < 0.05). Moreover, analysis of variance showed significant differences between the two kicking conditions in ankle, knee and hip joint displacements. The present study indicated that performing instep kicks after a double-cutting maneuver reduces ball and foot speed probably due to increasing joint frontal and transverse plane rotations. Improvements in the performance of the cutting maneuver task through training might result in better transfer of energy and speed to the kicking task thus permitting players to perform more powerful kicks under realistic game conditions. PMID:21560750

  12. Defect characterization in the diamond cutting tools

    SciTech Connect

    Zeren, Muzaffer . E-mail: zeren@kou.edu.tr; Karagoez, Sadi

    2006-08-15

    In this study, a general defect characterization in the diamond cutting tools used in natural stone cutting has been investigated. Transverse rupture tests were carried out with different matrix and diamond compositions. In these defect characterization studies on diamond cutting tool materials various microstructural analyses were performed using the techniques of light microscopy (LM), scanning electron microscopy (SEM), energy-dispersed X-ray spectrography (EDX) and image analysis (IA)

  13. Cutting sound enhancement system for mining machines

    DOEpatents

    Leigh, Michael C.; Kwitowski, August J.

    1992-01-01

    A cutting sound enhancement system (10) for transmitting an audible signal from the cutting head (101) of a piece of mine machinery (100) to an operator at a remote station (200), wherein, the operator using a headphone unit (14) can monitor the difference in sounds being made solely by the cutting head (101) to determine the location of the roof, floor, and walls of a coal seam (50).

  14. Duel-Plane Optical Disdrometer

    NASA Astrophysics Data System (ADS)

    Winsky, B. E.; Eichinger, W. E.

    2011-12-01

    Acquiring better drop-size distributions of rainfall will improve our understanding of the spatial and temporal variability of rainfall. In order to fully capture the spatial and temporal variability of rainfall, a robust, calibration free, low-cost instrument that provides an accurate drop-size distribution is required. Therefore, The University of Iowa Lidar Group has developed and built a new duel-plane optical disdrometer that meets these criteria. Two sheets of laser light, vertically spaced by 1 cm are produced by two 670nm laser beams passing through a collecting lens and culminating lens, respectively. The two sheets of laser light then pass through a convex lens located 20 cm from the lasers that focuses the light on a photo detector. A computer reads in and stores the voltages at 10 kHz. The velocity, diameter, shape and drop-size distribution of raindrops are extracted from the voltage measurements. Rainfall data collected in Iowa City, IA tested our disdrometer's robustness and accuracy of providing drop-size distributions. Our distrometer is advantageous because it is simple, low-cost, and requires no calibration.

  15. Reflections on the Hyperbolic Plane

    NASA Astrophysics Data System (ADS)

    Lecian, Orchidea Maria

    2013-12-01

    The most general solution to the Einstein equations in 4 = 3 + 1 dimensions in the asymptotic limit close to the cosmological singularity under the BKL (Belinskii-Khalatnikov-Lifshitz) hypothesis can be visualized by the behavior of a billiard ball in a triangular domain on the Upper Poincaré Half Plane (UPHP). The billiard system (named "big billiard") can be schematized by dividing the successions of trajectories according to Poincaré return map on the sides of the billiard table, according to the paradigms implemented by the BKL investigation and by the CB-LKSKS (Chernoff-Barrow-Lifshitz-Khalatnikov-Sinai-Khanin-Shchur) one. Different maps are obtained, according to different symmetry-quotienting mechanisms used to analyze the dynamics. In the inhomogeneous case, new structures have been uncovered, such that, in this framework, the billiard table (named "small billiard") consists of 1/6 of the previous one. The connections between the symmetry-quotienting mechanisms are further investigated on the UPHP. The relation between the complete billiard and the small billiard are also further explained according to the role of Weyl reflections. The quantum properties of the system are sketched as well, and the physical interpretation of the wave function is further developed. In particular, a physical interpretation for the symmetry-quotienting maps is proposed.

  16. Radioactivity in the galactic plane

    NASA Technical Reports Server (NTRS)

    Walraven, G. D.; Haymes, R. C.

    1976-01-01

    The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.

  17. Directed self-assembly cut mask assignment for unidirectional design

    NASA Astrophysics Data System (ADS)

    Ou, Jiaojiao; Yu, Bei; Gao, Jhih-Rong; Pan, David Z.

    2015-07-01

    Recently, directed self-assembly (DSA) has emerged as a promising lithography solution for cut manufacturing. We perform a comprehensive study on the DSA aware mask optimization problem to provide a DSA friendly design on cut layers. We first formulate the problem as an integer linear programming (ILP) to assign cuts to different guiding templates, targeting both conflict minimization and line-end extension minimization. As ILP may not be scalable for very large size problems, we then propose two speed-up strategies. The first one is to decompose the initial problem into smaller ones and solve them separately, followed by solution merging without much loss of quality. The second one is using the set cover algorithm to decide the DSA guiding pattern assignment, and then legalize the template placement. Our approaches can be naturally extended to handle arbitrary DSA guiding template patterns with complicated shapes. Experimental results show that our methodologies can significantly improve the DSA friendly, i.e., both the unresolved pattern number and the line-end extensions can be reduced.

  18. A heuristic for constrained T-shape cutting patterns of circular items

    NASA Astrophysics Data System (ADS)

    Cui, Yaodong; Huang, Baixiong

    2011-08-01

    The cutting and stamping process is often used to divide metal plate into circular items. It contains the cutting and stamping stages. A guillotine machine divides the plate into strips at the cutting stage. Each strip contains items of the same type. A press stamps out the items from the strips at the stamping stage. T-shape patterns are often used at the cutting stage. A cut divides a T-shape pattern into an X-segment of horizontal strips and a Y-segment of vertical strips. The position of the dividing cut should be determined such that the pattern value is maximized. A heuristic for constrained T-shape patterns is presented. For each position of the dividing cut, it generates an optimal strip layout on the Y-segment using all items, and generates another optimal strip layout on the X-segment using the remaining items. Computational results indicate that the algorithm is efficient in improving material utilization.

  19. Machining Challenges: Macro to Micro Cutting

    NASA Astrophysics Data System (ADS)

    Shunmugam, M. S.

    2016-04-01

    Metal cutting is an important machining operation in the manufacture of almost all engineering components. Cutting technology has undergone several changes with the development of machine tools and cutting tools to meet challenges posed by newer materials, complex shapes, product miniaturization and competitive environments. In this paper, challenges in macro and micro cutting are brought out. Conventional and micro end-milling are included as illustrative examples and details are presented along with discussion. Lengthy equations are avoided to the extent possible, as the emphasis is on the basic concepts.

  20. Advanced cryogenics for cutting tools. Final report

    SciTech Connect

    Lazarus, L.J.

    1996-10-01

    The purpose of the investigation was to determine if cryogenic treatment improved the life and cost effectiveness of perishable cutting tools over other treatments or coatings. Test results showed that in five of seven of the perishable cutting tools tested there was no improvement in tool life. The other two tools showed a small gain in tool life, but not as much as when switching manufacturers of the cutting tool. The following conclusions were drawn from this study: (1) titanium nitride coatings are more effective than cryogenic treatment in increasing the life of perishable cutting tools made from all cutting tool materials, (2) cryogenic treatment may increase tool life if the cutting tool is improperly heat treated during its origination, and (3) cryogenic treatment was only effective on those tools made from less sophisticated high speed tool steels. As a part of a recent detailed investigation, four cutting tool manufacturers and two cutting tool laboratories were queried and none could supply any data to substantiate cryogenic treatment of perishable cutting tools.

  1. A finite element model for ultrasonic cutting.

    PubMed

    Lucas, Margaret; MacBeath, Alan; McCulloch, Euan; Cardoni, Andrea

    2006-12-22

    Using a single-blade ultrasonic cutting device, a study of ultrasonic cutting of three very different materials is conducted using specimens of cheese, polyurethane foam and epoxy resin. Initial finite element models are created, based on the assumption that the ultrasonic blade causes a crack to propagate in a controlled mode 1 opening, and these are validated against experimental data from three point bend fracture tests and ultrasonic cutting experiments on the materials. Subsequently, the finite element model is developed to represent ultrasonic cutting of a multi-layered material. Materials are chosen whose properties allow a model to be developed that could represent a multi-layer food product or biological structure, to enable ultrasonic cutting systems to be designed for applications both in the field of food processing and surgical procedures. The model incorporates an estimation of the friction condition between the cutting blade and the material to be cut and allows adjustment of the frequency, cutting amplitude and cutting speed. PMID:16814351

  2. Cutting food in terrestrial carnivores and herbivores.

    PubMed

    Sanson, Gordon

    2016-06-01

    Insects and mammals cut their food up into small pieces to facilitate ingestion and chemical digestion. Teeth and jaws act as cutting tools, but, unlike engineering tools designed for a specific purpose, must generally cope with substantial variation in food properties and work at many scales. Knowing how teeth and jaws work effectively requires an understanding of the cutting on the edges and the mechanisms that remove cut material. Variability and heterogeneity of diet properties are not well known, and, for example, may be higher and overlap more in the browsing and grazing categories of plant diets. A reinterpretation of tooth function in large mammal browsers and grazers is proposed. PMID:27274799

  3. A Collaborative Knowledge Plane for Autonomic Networks

    NASA Astrophysics Data System (ADS)

    Mbaye, Maïssa; Krief, Francine

    Autonomic networking aims to give network components self-managing capabilities. Several autonomic architectures have been proposed. Each of these architectures includes sort of a knowledge plane which is very important to mimic an autonomic behavior. Knowledge plane has a central role for self-functions by providing suitable knowledge to equipment and needs to learn new strategies for more accuracy.However, defining knowledge plane's architecture is still a challenge for researchers. Specially, defining the way cognitive supports interact each other in knowledge plane and implementing them. Decision making process depends on these interactions between reasoning and learning parts of knowledge plane. In this paper we propose a knowledge plane's architecture based on machine learning (inductive logic programming) paradigm and situated view to deal with distributed environment. This architecture is focused on two self-functions that include all other self-functions: self-adaptation and self-organization. Study cases are given and implemented.

  4. Collinearity-preserving functions between Desarguesian planes

    PubMed Central

    Carter, David S.; Vogt, Andrew

    1980-01-01

    Using concepts from valuation theory, we obtain a characterization of all collinearity-preserving functions from one affine or projective Desarguesian plane into another. The case in which the planes are projective and the range contains a quadrangle has been treated previously in the literature. Our results permit one or both planes to be affine and include cases in which the range contains a triangle but no quadrangle. A key theorem is that, with the exception of certain embeddings defined on planes of order 2 and 3, every collinearity-preserving function from one affine Desarguesian plane into another can be extended to a collinearity-preserving function between enveloping projective planes. PMID:16592845

  5. Extramedullary versus intramedullary tibial cutting guides in megaprosthetic total knee replacement

    PubMed Central

    2012-01-01

    Background In a standard total knee replacement, tibial component alignment is a key factor for the long term success of the surgery. The purpose of this study is to compare the accuracy of extramedullary and intramedullary tibial cutting guides used in indigenous and imported implants respectively, in positioning of the tibial components in megaprosthetic knee replacements. Methods A comparative study of the accuracy of extramedullary and intramedullary tibial cutting guides was carried out in 92 megaprosthetic knee replacements for distal femoral tumors. For the proximal tibia cut for tibial component placement, an extramedullary guide was used in 65 patients and an intramedullary guide was used in 27 patients. Tibial component alignment angles were measured in postoperative X-rays with the help of CAD software. Results There was more varus placement in coronal plane with extramedullary cutting guide (−1.18 +/− 2.4 degrees) than the intramedullary guide (−0.34 +/− 2.31 degrees) but this did not reach statistical significance. The goal of 90 +/− 2 degrees alignment of tibial component was achieved in 54% of patients in the extramedullary group versus 67% in the intramedullary group. In terms of sagittal plane alignment, extramedullary guide showed less accurate results (2.09 +/− 2.4 degrees) than intramedullary guide (0.50 +/− 3.80 degrees) for tibial component alignment, though 78% of patients were aligned within the goal of 0–5 degrees of tibial slope angle in extramedullary group versus 63% in intramedullary group. The mean error in the measurements due to rotation of the knee during taking the X-rays was less than 0.1 degrees and distribution of the X-rays with the rotation of knee was similar in both the groups. Conclusions Overall, in megaprosthetic knee replacement intramedullary guides gave more accurate results in sagittal plane and exhibited similar variability as of extramedullary guides in coronal plane. PMID:23031403

  6. Sagittal plane biomechanics. American Diabetes Association.

    PubMed

    Dananberg, H J

    2000-01-01

    During walking, the center of body mass must pass from behind the weightbearing foot to in front of it. For this to take place, the foot must function as a sagittal plane pivot. Because the range required for this motion is approximately five times as great as both frontal and transverse plane motion, its evaluation should become an essential part of a podiatric biomechanical assessment. Lack of proper sagittal plane motion and its sequelae are described. PMID:10659532

  7. Nanostructured carbon films with oriented graphitic planes

    SciTech Connect

    Teo, E. H. T.; Kalish, R.; Kulik, J.; Kauffmann, Y.; Lifshitz, Y.

    2011-03-21

    Nanostructured carbon films with oriented graphitic planes can be deposited by applying energetic carbon bombardment. The present work shows the possibility of structuring graphitic planes perpendicular to the substrate in following two distinct ways: (i) applying sufficiently large carbon energies for deposition at room temperature (E>10 keV), (ii) utilizing much lower energies for deposition at elevated substrate temperatures (T>200 deg. C). High resolution transmission electron microscopy is used to probe the graphitic planes. The alignment achieved at elevated temperatures does not depend on the deposition angle. The data provides insight into the mechanisms leading to the growth of oriented graphitic planes under different conditions.

  8. Recent developments in surgical skin planing.

    PubMed

    AYRES, S; WILSON, J W; LUIKART, R

    1958-02-01

    In surgical skin planing steel wire brushes have been largely replaced by the less hazardous diamond chip burs or "fraises" and serrated steel wheels. In addition to acne pits and wrinkling, multiple actinic (senile) keratoses are an important indication for planing. Planing provides a nonscarring method for the treatment of existing keratoses, as well as a prophylaxis against skin cancer by replacing the sun-damaged, precancerous epidermis with new epidermal cells derived from the cutaneous adnexa (pilosebaceous and sweat gland units). There are clinical landmarks indicating the depth of planing which can serve as a guide to the operator and can be correlated with microscopic findings. The results of experiments on the comparative effects of refrigerants on animal and human skin indicate that human facial skin can tolerate considerable freezing with ethyl chloride or dichlorotetrafluoroethane (Freon 114) but that mixtures containing large proportions of the much colder dichlorodifluoromethane (Freon 12) may be undesirable. Refreezing an area of the skin in order to perform a more adequate planing is not considered hazardous.THE REGENERATION OF THE SKIN FOLLOWING PLANING HAS THREE COMPONENTS: Epidermal, adnexal and dermal. The cells of the epidermis and the adnexa are equipotential. A knowledge of the anatomy of the acne pit enables the operator to decide which pits can be benefited by planing and which should be excised before planing. The successful treatment of acne pits of the face by planing in patients having keloids elsewhere on the body is reported. PMID:13500217

  9. Digital scanner infrared focal plane technology

    NASA Astrophysics Data System (ADS)

    Ortiz, M. A.; Malone, N. R.; Harris, M.; Shin, J.; Byers, S.; Price, D.; Vampola, J.

    2011-09-01

    Advancements in finer geometry and technology advancements in circuit design now allow placement of digital architecture on cryogenic focal planes while using less power than heritage analog designs. These advances in technology reduce the size, weight, and power of modern focal planes. In addition, the interface to the focal plane is significantly simplified and is more immune to Electromagnetic Interference (EMI). The cost of the customer's instrument after integration with the digital scanning Focal Plane Array (FPA) has been significantly reduced by placing digital architecture such as Analog to digital convertors and Low Voltage Differential Signaling (LVDS) Inputs and Outputs (I/O) on the Read Out Integrated Circuit (ROIC).

  10. Approximate labeling via graph cuts based on linear programming.

    PubMed

    Komodakis, Nikos; Tziritas, Georgios

    2007-08-01

    A new framework is presented for both understanding and developing graph-cut-based combinatorial algorithms suitable for the approximate optimization of a very wide class of Markov Random Fields (MRFs) that are frequently encountered in computer vision. The proposed framework utilizes tools from the duality theory of linear programming in order to provide an alternative and more general view of state-of-the-art techniques like the \\alpha-expansion algorithm, which is included merely as a special case. Moreover, contrary to \\alpha-expansion, the derived algorithms generate solutions with guaranteed optimality properties for a much wider class of problems, for example, even for MRFs with nonmetric potentials. In addition, they are capable of providing per-instance suboptimality bounds in all occasions, including discrete MRFs with an arbitrary potential function. These bounds prove to be very tight in practice (that is, very close to 1), which means that the resulting solutions are almost optimal. Our algorithms' effectiveness is demonstrated by presenting experimental results on a variety of low-level vision tasks, such as stereo matching, image restoration, image completion, and optical flow estimation, as well as on synthetic problems. PMID:17568146

  11. The Location of the Maximum Temperature on the Cutting Edges of a Drill

    SciTech Connect

    Bono, M J; Ni, J

    2005-01-07

    This study analyzes the temperature profile along the cutting edges of a drill and describes how the temperature on the chisel edge can exceed the temperature on the primary cutting edges. A finite element model predicts the temperature distribution in the drill, where the heat flux loads applied to the finite element model are determined from analytical equations. The model for the heat flux loads considers both the heat generated on the shear plane and the heat generated on the rake face of the tool to determine the amount of heat flowing into the tool on each segment of the cutting edges. Contrary to the conventional belief that the maximum temperature occurs near the outer corner of the drill, the model predicts that the maximum temperature occurs on the chisel edge, which is consistent with experimental measurements of the temperature profile.

  12. The best of both worlds: automated CMP polishing of channel-cut monochromators

    SciTech Connect

    Kasman, Elina; Erdmann, Mark; Stoupin, Stanislav

    2015-09-03

    The use of a channel-cut monochromator is the most straightforward method to ensure that the two reflection surfaces maintain alignment between crystallographic planes without the need for complicated alignment mechanisms. Three basic characteristics that affect monochromator performance are: subsurface damage which contaminates spectral purity; surface roughness which reduces efficiency due to scattering; and surface figure error which imparts intensity structure and coherence distortion in the beam. Standard chemical-mechanical polishing processes and equipment are used when the diffracting surface is easily accessible, such as for single-bounce monochromators. Due to the inaccessibly of the surfaces inside a channel-cut monochromator for polishing, these optics are generally wet-etched for their final processing. This results in minimal subsurface damage, but very poor roughness and figure error. A new CMP channel polishing instrument design is presented which allows the internal diffracting surface quality of channel-cut crystals to approach that of conventional single-bounce monochromators

  13. Experimental test of theory for the stability of partially saturated vertical cut slopes

    USGS Publications Warehouse

    Morse, Michael M.; Lu, N.; Wayllace, Alexandra; Godt, Jonathan W.; Take, W.A.

    2014-01-01

    This paper extends Culmann's vertical-cut analysis to unsaturated soils. To test the extended theory, unsaturated sand was compacted to a uniform porosity and moisture content in a laboratory apparatus. A sliding door that extended the height of the free face of the slope was lowered until the vertical cut failed. Digital images of the slope cross section and upper surface were acquired concurrently. A recently developed particle image velocimetry (PIV) tool was used to quantify soil displacement. The PIV analysis showed strain localization at varying distances from the sliding door prior to failure. The areas of localized strain were coincident with the location of the slope crest after failure. Shear-strength and soil-water-characteristic parameters of the sand were independently tested for use in extended analyses of the vertical-cut stability and of the failure plane angle. Experimental failure heights were within 22.3% of the heights predicted using the extended theory.

  14. The best of both worlds: automated CMP polishing of channel-cut monochromators

    NASA Astrophysics Data System (ADS)

    Kasman, Elina; Erdmann, Mark; Stoupin, Stanislav

    2015-09-01

    The use of a channel-cut monochromator is the most straightforward method to ensure that the two reflection surfaces maintain alignment between crystallographic planes without the need for complicated alignment mechanisms. Three basic characteristics that affect monochromator performance are: subsurface damage which contaminates spectral purity; surface roughness which reduces efficiency due to scattering; and surface figure error which imparts intensity structure and coherence distortion in the beam. Standard chemical-mechanical polishing processes and equipment are used when the diffracting surface is easily accessible, such as for single-bounce monochromators. Due to the inaccessibly of the surfaces inside a channel-cut monochromator for polishing, these optics are generally wet-etched for their final processing. This results in minimal subsurface damage, but very poor roughness and figure error. A new CMP channel polishing instrument design is presented which allows the internal diffracting surface quality of channel-cut crystals to approach that of conventional single-bounce monochromators.

  15. The effect of cutting speed on residual stresses when orthogonal cutting TC4

    NASA Astrophysics Data System (ADS)

    Liu, Chaofeng; Wang, Zengqiang; Zhang, Guang; Liu, Lei

    2015-09-01

    As one of the most important parameters in mental cutting, cutting speed has a significant influence on residual stress. Finite element method and experiment method are used to study the relationship between cutting speed and residual stress when orthogonal cutting TC4 titanium alloy. The result of simulation and experiment shows that: when the cutting speed is low, the residual stress in axial direction is compressive stress and gradually converts to tensile stress with the increase of cutting speed, but it will convert to compressive stress again if the cutting speed continues to increase; the residual stress in tangential direction is constant to compressive stress and it will decrease with the increase of cutting speed.

  16. Optimization of Straight Cylindrical Turning Using Artificial Bee Colony (ABC) Algorithm

    NASA Astrophysics Data System (ADS)

    Prasanth, Rajanampalli Seshasai Srinivasa; Hans Raj, Kandikonda

    2016-06-01

    Artificial bee colony (ABC) algorithm, that mimics the intelligent foraging behavior of honey bees, is increasingly gaining acceptance in the field of process optimization, as it is capable of handling nonlinearity, complexity and uncertainty. Straight cylindrical turning is a complex and nonlinear machining process which involves the selection of appropriate cutting parameters that affect the quality of the workpiece. This paper presents the estimation of optimal cutting parameters of the straight cylindrical turning process using the ABC algorithm. The ABC algorithm is first tested on four benchmark problems of numerical optimization and its performance is compared with genetic algorithm (GA) and ant colony optimization (ACO) algorithm. Results indicate that, the rate of convergence of ABC algorithm is better than GA and ACO. Then, the ABC algorithm is used to predict optimal cutting parameters such as cutting speed, feed rate, depth of cut and tool nose radius to achieve good surface finish. Results indicate that, the ABC algorithm estimated a comparable surface finish when compared with real coded genetic algorithm and differential evolution algorithm.

  17. New stereology for the recovery of grain-boundary plane distributions in the crystal frame

    NASA Astrophysics Data System (ADS)

    Larsen, Ryan J.; Adams, Brent L.

    2004-07-01

    A new experimental method is given for recovering the probability-distribution function S v (hat n_A |Δ g). The function S v (hat n_A |Δ g) is the grain-boundary area per unit volume as a function of grain-boundary plane orientation (hat n_A ), given a lattice misorientation (Δ g) between the adjoining grains. The grain-boundary normal (hat n_A ) is expressed in the crystal frame in which the misorientation Δ g originates. The proposed method recovers the three-dimensional S v (hat n_A |Δ g) function using data taken from two-dimensional section planes. The method requires the measurement of many grain-boundary trace (in-plane) angles and lengths associated with grain boundaries of lattice misorientation. All such boundary traces may be observed from a single section plane if the crystallographic texture is sufficiently random. In heavily textured microstructures, the method requires the researcher to observe traces from multiple oblique section planes cut through the material. A method of quantitatively estimating whether the texture is sufficiently random is given. Simulations on both textured and nontextured microstructures demonstrate the validity of the method. Experimentally, the new method is used to analyze boundaries of misorientation (Σ3) observed in 304 stainless steel. Calculated grain-boundary plane-probability functions are shown to be consistent with what is already known.

  18. An Integrated Method Based on PSO and EDA for the Max-Cut Problem.

    PubMed

    Lin, Geng; Guan, Jian

    2016-01-01

    The max-cut problem is NP-hard combinatorial optimization problem with many real world applications. In this paper, we propose an integrated method based on particle swarm optimization and estimation of distribution algorithm (PSO-EDA) for solving the max-cut problem. The integrated algorithm overcomes the shortcomings of particle swarm optimization and estimation of distribution algorithm. To enhance the performance of the PSO-EDA, a fast local search procedure is applied. In addition, a path relinking procedure is developed to intensify the search. To evaluate the performance of PSO-EDA, extensive experiments were carried out on two sets of benchmark instances with 800 to 20,000 vertices from the literature. Computational results and comparisons show that PSO-EDA significantly outperforms the existing PSO-based and EDA-based algorithms for the max-cut problem. Compared with other best performing algorithms, PSO-EDA is able to find very competitive results in terms of solution quality. PMID:26989404

  19. An Integrated Method Based on PSO and EDA for the Max-Cut Problem

    PubMed Central

    Lin, Geng; Guan, Jian

    2016-01-01

    The max-cut problem is NP-hard combinatorial optimization problem with many real world applications. In this paper, we propose an integrated method based on particle swarm optimization and estimation of distribution algorithm (PSO-EDA) for solving the max-cut problem. The integrated algorithm overcomes the shortcomings of particle swarm optimization and estimation of distribution algorithm. To enhance the performance of the PSO-EDA, a fast local search procedure is applied. In addition, a path relinking procedure is developed to intensify the search. To evaluate the performance of PSO-EDA, extensive experiments were carried out on two sets of benchmark instances with 800 to 20000 vertices from the literature. Computational results and comparisons show that PSO-EDA significantly outperforms the existing PSO-based and EDA-based algorithms for the max-cut problem. Compared with other best performing algorithms, PSO-EDA is able to find very competitive results in terms of solution quality. PMID:26989404

  20. Extending the size-parameter range for plane-wave light scattering from infinite homogeneous circular cylinders

    SciTech Connect

    Hau-Riege, S

    2005-04-12

    We have developed an algorithm that extends the possible size-parameter range for the calculation of plane-wave light scattering from infinite homogeneous circular cylinders using a Mie-type analysis. Our algorithm is based on the calculation of the ratios of Bessel functions instead of calculating the Bessel functions or their logarithmic derivatives directly. We have found that this algorithm agrees with existing methods (when those methods converge). We have also found that our algorithm converges in cases of very large size parameters, in which case other algorithms often do not.

  1. Feature-aided multiple target tracking in the image plane

    NASA Astrophysics Data System (ADS)

    Brown, Andrew P.; Sullivan, Kevin J.; Miller, David J.

    2006-05-01

    Vast quantities of EO and IR data are collected on airborne platforms (manned and unmanned) and terrestrial platforms (including fixed installations, e.g., at street intersections), and can be exploited to aid in the global war on terrorism. However, intelligent preprocessing is required to enable operator efficiency and to provide commanders with actionable target information. To this end, we have developed an image plane tracker which automatically detects and tracks multiple targets in image sequences using both motion and feature information. The effects of platform and camera motion are compensated via image registration, and a novel change detection algorithm is applied for accurate moving target detection. The contiguous pixel blob on each moving target is segmented for use in target feature extraction and model learning. Feature-based target location measurements are used for tracking through move-stop-move maneuvers, close target spacing, and occlusion. Effective clutter suppression is achieved using joint probabilistic data association (JPDA), and confirmed target tracks are indicated for further processing or operator review. In this paper we describe the algorithms implemented in the image plane tracker and present performance results obtained with video clips from the DARPA VIVID program data collection and from a miniature unmanned aerial vehicle (UAV) flight.

  2. Signal processing of microbolometer infrared focal-plane arrays

    NASA Astrophysics Data System (ADS)

    Zhang, Junju; Qian, Yunsheng; Chang, Benkang; Xing, Suxia; Sun, Lianjun

    2005-01-01

    A 320×240-uncooled-microbolometer-based signal processing circuit for infrared focal-plane arrays is presented, and the software designs of this circuit system are also discussed in details. This signal processing circuit comprises such devices as FPGA, D/A, A/D, SRAM, Flash, DSP, etc., among which, FPGA is the crucial part, which realizing the generation of drive signals for infrared focal-plane, nonuniformity correction, image enhancement and video composition. The device of DSP, mainly offering auxiliary functions, carries out communication with PC and loads data when power-up. The phase locked loops (PLL) is used to generate high-quality clocks with low phase dithering and multiple clocks are to used satisfy the demands of focal-plane arrays, A/D, D/A and FPGA. The alternate structure is used to read or write SRAM in order to avoid the contradiction between different modules. FIFO embedded in FPGA not only makes full use of the resources of FPGA but acts as the channel between different modules which have different-speed clocks. What's more, working conditions, working process, physical design and management of the circuit are discussed. In software designing, all the function modules realized by FPGA and DSP devices, which are mentioned in the previous part, are discussed explicitly. Particularly to the nonuniformity correction module, the pipeline structure is designed to improve the working frequency and the ability to realize more complex algorithm.

  3. Combination of Ultrasonic Vibration and Cryogenic Cooling for Cutting Performance Improvement of Inconel 718 Turning

    NASA Astrophysics Data System (ADS)

    Lin, S. Y.; Chung, C. T.; Cheng, Y. Y.

    2011-01-01

    The main objective of this study is to develop a thermo-elastic-plastic coupling model, based on a combination skill of ultrasonically assisted cutting and cryogenic cooling, under large deformation for Inconel 718 alloy machining process. The improvement extent on cutting performance and tool life promotion may be examined from this investigation. The critical value of the strain energy density of the workpiece will be utilized as the chip separation and the discontinuous chip segmentation criteria. The forced convection cooling and a hydrodynamic lubrication model will be considered and formulated in the model. Finite element method will be applied to create a complete numerical solution for this ultrasonic vibration cutting model. During the analysis, the cutting tool is incrementally advanced forward with superimposed ultrasonic vibration in a back and forth step-by-step manner, from an incipient stage of tool-workpiece engagement to a steady state of chip formation, a whole simulation of orthogonal cutting process under plane strain deformation is thus undertaken. High shear strength induces a fluctuation phenomenon of shear angle, high shear strain rate, variation of chip types and chip morphology, tool-chip contact length variation, the temperature distributions within the workpiece, chip and tool, periodic fluctuation in cutting forces can be determined from the developed model. A complete comparison of machining characteristics between some different combinations of ultrasonically assisted cutting and cryogenic cooling with conventional cutting operation can be acquired. Finally, the high-speed turning experiment for Inconel 718 alloy will be taken in the laboratory to validate the accuracy of the model, and the progressive flank wear, crater wear, notching and chipping of the tool edge can also be measured in the experiments.

  4. Cut set-based risk and reliability analysis for arbitrarily interconnected networks

    DOEpatents

    Wyss, Gregory D.

    2000-01-01

    Method for computing all-terminal reliability for arbitrarily interconnected networks such as the United States public switched telephone network. The method includes an efficient search algorithm to generate minimal cut sets for nonhierarchical networks directly from the network connectivity diagram. Efficiency of the search algorithm stems in part from its basis on only link failures. The method also includes a novel quantification scheme that likewise reduces computational effort associated with assessing network reliability based on traditional risk importance measures. Vast reductions in computational effort are realized since combinatorial expansion and subsequent Boolean reduction steps are eliminated through analysis of network segmentations using a technique of assuming node failures to occur on only one side of a break in the network, and repeating the technique for all minimal cut sets generated with the search algorithm. The method functions equally well for planar and non-planar networks.

  5. Improving quality of fresh-cut tomatoes using a cutting edge technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Fresh-cut produce industry has experienced a double digit growth rate over the past decade. Fresh-cut tomatoes are in high demand from both the food service and retail sectors. However, the many technical challenges that exist in maintaining the quality and microbial food safety of fresh-cut to...

  6. Improving Pathogen Reduction by Chlorine Wash Prior to Cutting in Fresh-Cut Processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Currently, most fresh-cut processing facilities in the United States use chlorinated water or other sanitizer solutions for microbial reduction after lettuce is cut. Freshly cut lettuce releases significant amounts of organic matter that negatively impacts the effectiveness of chlorine...

  7. Simplified cut core inductor design

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1974-01-01

    Although filter inductor designers have routinely tended to specify molypermalloy powder cores for use in high frequency power converters and pulse-width modulated switching regulators, there are sigificant advantages in specifying C cores and cut toroids fabricated from grain oriented silicon steels which should not be overlooked. Such steel cores can develop flux densities of 1.6 tesla, with useful linearity to 1.2 tesla, whereas molypermalloy cores carrying d.c. current have useful flux density capabilities only to about 0.3 tesla. The use of silicon steel cores thus makes it possible to design more compact cores, and therefore inductors of reduced volume, or conversely to provide greater load capacity in inductors of a given volume. Information is available which makes it possible to obtain quick and close approximations of significant parameters such as size, weight and temperature rise for silicon steel cores for breadboarding. Graphs, nomographs and tables are presented for this purpose, but more complete mathematical derivations of some of the important parameters are also included for a more rigorous treatment.

  8. Corner-cutting mining assembly

    DOEpatents

    Bradley, J.A.

    1981-07-01

    This invention resulted from a contract with the United States Department of Energy and relates to a mining tool. More particularly, the invention relates to an assembly capable of drilling a hole having a square cross-sectional shape with radiused corners. In mining operations in which conventional auger-type drills are used to form a series of parallel, cylindrical holes in a coal seam, a large amount of coal remains in place in the seam because the shape of the holes leaves thick webs between the holes. A higher percentage of coal can be mined from a seam by a means capable of drilling holes having a substantially square cross section. It is an object of this invention to provide an improved mining apparatus by means of which the amount of coal recovered from a seam deposit can be increased. Another object of the invention is to provide a drilling assembly which cuts corners in a hole having a circular cross section. These objects and other advantages are attained by a preferred embodiment of the invention.

  9. Overhead and operations: cutting where it counts.

    PubMed

    Shorr, Jay A

    2014-01-01

    To remain a profitable entity, whether a retail operation, manufacturing plant, or a medical practice, the common denominator is the same: where can you cut your costs, increase your revenue, and maintain additional profitability? Learning where to cut your operational expenses is as important to your business's profit-ability as bringing in additional dollars. PMID:25807622

  10. Syllable Cut Prosody in Early Middle English.

    ERIC Educational Resources Information Center

    Murray, Robert W.

    2000-01-01

    Approaches Middle English quantity changes as the consequence of the phonologization of a syllable cut prosody and provides new evidence for the relevance of syllable cut to the diachronic phonology of English. Evidence comes from partial reconstruction of Ihe phonological system of the early Middle English dialect presented in the "Ormulum,"…

  11. Microwave interferometer controls cutting depth of plastics

    NASA Technical Reports Server (NTRS)

    Heisman, R. M.; Iceland, W. F.

    1969-01-01

    Microwave interferometer system controls the cutting of plastic materials to a prescribed depth. The interferometer is mounted on a carriage with a spindle and cutting tool. A cross slide, mounted on the carriage, allows the interferometer and cutter to move toward or away from the plastic workpiece.

  12. Cut Next Winter's Heating Bill Today.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    1999-01-01

    Presents specific steps that help make schools energy efficient and cut costs. Four basic strategies are suggested that include creating a database of energy usage that can also catch the occasional billing error, investigating less obvious ways of cutting energy use, such as applying cellulose commercial spray as an insulation choice, and…

  13. Antimicrobial packaging for fresh-cut fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut fruits are minimally processed produce which are consumed directly at their fresh stage without any further kill step. Microbiological quality and safety are major challenges to fresh-cut fruits. Antimicrobial packaging is one of the innovative food packaging systems that is able to kill o...

  14. Drill cuttings disposal method and system

    SciTech Connect

    Jackson, J.E.

    1992-05-05

    This patent describes a system for producing a slurry of finely ground drill cuttings and a carrier liquid suitable for injection into an earth formation and the like and wherein the drill cuttings are produced during drilling operations from a drill cuttings/drilling fluids separation means. It comprises: receiving means for receiving a quantity of the drill cuttings; means for conducting the drill cuttings to the receiving means; means for conducting the carrier liquid to the receiving means; conduit means in communication with the receiving means for discharging a mixture of the drill cuttings and the carrier liquid from the receiving means; and a centrifugal pump connected to the receiving means for reducing the particle size of the drill cuttings so that a slurry of the drill cuttings and the carrier liquid may be prepared for injection into the space. A method for disposing of solids particles including earth particles into an earth formation comprising the steps of; providing a wellbore penetrating the earth formation and forming with the earth formation a space for receiving a slurry of the solids particles and a carrier liquid; providing a system for generating a slurry formed of the solids particles and the carrier liquid, mixing the solids particles with the carrier liquid; reducing the particle size of the solids particles by shearing action on the solids particles to form a viscous fluid comprising the slurry; and conducting the slurry to the injection pump and injecting the slurry into the space.

  15. Plywood Inlays Thourgh CO2 Laser Cutting

    NASA Astrophysics Data System (ADS)

    Pires, Margarida C.; Araujo, J. L.; Teixeira, M. Ribau; Rodrigues, F. Carvalho

    1989-07-01

    Furniture with inlays is rather expensive. This is so on two accounts: Firstly, furniture with inlays is generally manufactured with solid wood.Secondly,wood carving and figure cutting are both time consuming and they produce a high rate of rejections. To add to it all the cutting and carving of minute figures requires an outstanding craftmanship. In fact the craftman is in most instance the artist and also the manufacturer. While desiring that the high artistic level is maintained in the industry the search for new method to produce inlays for furniture in not son expensive materials and to produce them in a repetitive and flexible way laser cutting of plywood was found to be quite suitable. This paper presents the charts for CO2 laser cutting of both positive and negatives in several types of plywood. The main problem is not so much the cutting of the positive and negatives pieces but to be able to cut the piece in a way that the fitting is done without any problems caused by the ever present charring effect, which takes palce at the edges of the cut pieces. To minimise this aspect positive and negative pieces have to be cut under stringent focusing conditions and with slight different scales. The condittions for our machine are presented.

  16. President's Budget Would Cut Education Spending

    ERIC Educational Resources Information Center

    Davis, Michelle R.

    2006-01-01

    This article discusses President Bush's budget cut on education spending. The president's blueprint for federal education spending in the next fiscal year includes a high-profile plan to boost math and science education, new money for private school vouchers, a renewed push to improve high schools--and the most drastic cut in Department of…

  17. Scissors: More than a Cut Above

    ERIC Educational Resources Information Center

    Suzanne, Teri

    2005-01-01

    Scissors are a unique interactive tool when successfully used, allowing teachers and students to recognize and explore each other's creative ability while nurturing mutual communication. Freehand cutting gives children freedom to create as they cut. Scissors have the power to improve fine motor skills, stimulate creative imagination, reinforce…

  18. Vee-notch tool cuts specimens

    NASA Technical Reports Server (NTRS)

    Spier, R. A.

    1970-01-01

    Triangular cutting tool uses carbide tips for notching heat-treated or abrasive materials, and alloys subjected to high structural stresses. The tool is rigidly mounted in a slot of mating contour to prevent deflection during cutting of tensile specimens. No other expensive machine equipment is required.

  19. Meat Cutting Classes--Popular with Adults

    ERIC Educational Resources Information Center

    Mostad, James; Carpentier, Dale

    1976-01-01

    Presents a session by session description of a "meats" class, which is offered to high school students (9-week period) and adults (8-week period). The classes cover identification of cuts (beef, sheep, hogs, and veal; grades and grading of live animals and carcasses; economics of butchering and cutting your own meat; actual slaughtering; and the…

  20. Postharvest: Cut flowers and potted plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past fifty years, the cut flower market has changed dramatically, from a local market with growers located on city outskirts, to a global one; flowers and cut foliage sourced from throughout the world are sold as bunches or combined into arrangements and bouquets in the major target markets. ...

  1. Don't Camouflage Budget Cuts.

    ERIC Educational Resources Information Center

    DeLuca, Nicholas M.

    1982-01-01

    Instead of shielding the public from the effects of budget cuts by making small across-the-board cuts on many programs, school administrators should slash whole programs. This will maintain the system's overall educational effectiveness while making clear the consequences of the public's political actions. (Author/RW)

  2. Cutting fluid for machining fissionable materials

    SciTech Connect

    Duerksen, W.K.; Googin, J.M.; Napier, B. Jr.

    1982-01-28

    The present invention is directed to a cutting fluid for machining fissionable material. The cutting fluid is formed of glycol, water and a boron compound in an adequate concentration for effective neutron attenuation so as to inhibit criticality incidents during machining.

  3. Drilling subsurface wellbores with cutting structures

    DOEpatents

    Mansure, Arthur James; Guimerans, Rosalvina Ramona

    2010-11-30

    A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

  4. Cutting Watermelon: Lessons in Instructional Coaching

    ERIC Educational Resources Information Center

    Sandstead, Martha

    2016-01-01

    Literacy coordinator Martha Sandstead finds inspiration for her coaching work in a quote from civil rights organizer Lawrence Guyot: "Let's say you're riding past a picnic, and people are cuttin' watermelons. You don't immediately go and say, "stop the watermelon cutting" and let's talk. … You cut some watermelons, or you help…

  5. Cutting tool form compensation system and method

    DOEpatents

    Barkman, W.E.; Babelay, E.F. Jr.; Klages, E.J.

    1993-10-19

    A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed. 9 figures.

  6. Cutting tool form compensaton system and method

    DOEpatents

    Barkman, William E.; Babelay, Jr., Edwin F.; Klages, Edward J.

    1993-01-01

    A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed.

  7. 33 CFR 117.161 - Honker Cut.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Honker Cut. 117.161 Section 117.161 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements California § 117.161 Honker Cut. The draw of the San Joaquin County (Eightmile Road) bridge, mile...

  8. 33 CFR 117.143 - Bishop Cut.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Bishop Cut. 117.143 Section 117.143 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin County highway bridge, mile 1.0 between...

  9. Automatic Recognition of Fetal Facial Standard Plane in Ultrasound Image via Fisher Vector.

    PubMed

    Lei, Baiying; Tan, Ee-Leng; Chen, Siping; Zhuo, Liu; Li, Shengli; Ni, Dong; Wang, Tianfu

    2015-01-01

    Acquisition of the standard plane is the prerequisite of biometric measurement and diagnosis during the ultrasound (US) examination. In this paper, a new algorithm is developed for the automatic recognition of the fetal facial standard planes (FFSPs) such as the axial, coronal, and sagittal planes. Specifically, densely sampled root scale invariant feature transform (RootSIFT) features are extracted and then encoded by Fisher vector (FV). The Fisher network with multi-layer design is also developed to extract spatial information to boost the classification performance. Finally, automatic recognition of the FFSPs is implemented by support vector machine (SVM) classifier based on the stochastic dual coordinate ascent (SDCA) algorithm. Experimental results using our dataset demonstrate that the proposed method achieves an accuracy of 93.27% and a mean average precision (mAP) of 99.19% in recognizing different FFSPs. Furthermore, the comparative analyses reveal the superiority of the proposed method based on FV over the traditional methods. PMID:25933215

  10. Automatic Recognition of Fetal Facial Standard Plane in Ultrasound Image via Fisher Vector

    PubMed Central

    Lei, Baiying; Tan, Ee-Leng; Chen, Siping; Zhuo, Liu; Li, Shengli; Ni, Dong; Wang, Tianfu

    2015-01-01

    Acquisition of the standard plane is the prerequisite of biometric measurement and diagnosis during the ultrasound (US) examination. In this paper, a new algorithm is developed for the automatic recognition of the fetal facial standard planes (FFSPs) such as the axial, coronal, and sagittal planes. Specifically, densely sampled root scale invariant feature transform (RootSIFT) features are extracted and then encoded by Fisher vector (FV). The Fisher network with multi-layer design is also developed to extract spatial information to boost the classification performance. Finally, automatic recognition of the FFSPs is implemented by support vector machine (SVM) classifier based on the stochastic dual coordinate ascent (SDCA) algorithm. Experimental results using our dataset demonstrate that the proposed method achieves an accuracy of 93.27% and a mean average precision (mAP) of 99.19% in recognizing different FFSPs. Furthermore, the comparative analyses reveal the superiority of the proposed method based on FV over the traditional methods. PMID:25933215

  11. Application of high-rate cutting tools

    NASA Astrophysics Data System (ADS)

    Moriarty, John L., Jr.

    1989-03-01

    Widespread application of the newest high-rate cutting tools to the most appropriate jobs is slowed by the sheer magnitude of developments in tool types, materials, workpiece applications, and by the rapid pace of change. Therefore, a study of finishing and roughing sizes of coated carbide inserts having a variety of geometries for single point turning was completed. The cutting tools were tested for tool life, chip quality, and workpiece surface finish at various cutting conditions with medium alloy steel. An empirical wear-life data base was established, and a computer program was developed to facilitate technology transfer, assist selection of carbide insert grades, and provide machine operating parameters. A follow-on test program was implemented suitable for next generation coated carbides, rotary cutting tools, cutting fluids, and ceramic tool materials.

  12. Solar Impulse's Solar-Powered Plane

    ScienceCinema

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2014-01-07

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  13. Solar Impulse's Solar-Powered Plane

    SciTech Connect

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2013-07-08

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  14. Slipping and Rolling on an Inclined Plane

    ERIC Educational Resources Information Center

    Aghamohammadi, Cina; Aghamohammadi, Amir

    2011-01-01

    In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient ([mu]). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is…

  15. Corn stalk orientation effect on mechanical cutting

    SciTech Connect

    Igathinathane, C.; Womac, A.R.; Sokhansanj, Shahabaddine

    2010-07-01

    Research efforts that increase the efficiency of size reduction of biomass can lead to a significant energy saving. This paper deals with the determination of the effect of sample orientation with respect to cutting element and quantify the possible cutting energy reduction, utilising dry corn stalks as the test material (15%e20% wet basis). To evaluate the mechanical cutting characteristics of corn stalks, a Warnere Bratzler device was modified by replacing its blunt edged cutting element with one having a 30_ single bevel sharp knife edge. Cutting force-deformation characteristics obtained with a universal testing machine were analysed to evaluate the orientation effects at perpendicular (90o), inclined (45o), and parallel (0o) orientations on internodes and nodes for cutting force, energy, ultimate stress, and specific energy of corn stalks. The corn stalks cutting force-displacement characteristics were found to differ with orientation, and internode and node material difference. Overall, the peak failure force, and the total cutting energy of internodes and nodes varied significantly (P < 0.05) with stalk cross-sectional area. The specific energy values (total energy per unit cut area) of dry corn stalk internodes ranged from 11.3 to 23.5 kN m_1, and nodes from 8.6 to 14.0 kN m_1. The parallel orientation (along grain) compared to perpendicular (across grain) produced a significant reduction of the cutting stress and the specific energy to one tenth or better for internodes, and to about one-fifth for nodes.

  16. Interactive 3D medical data cutting using closed curve with arbitrary shape.

    PubMed

    Ning, Hai; Yang, Rongqian; Ma, Amin; Wu, Xiaoming

    2015-03-01

    Interactive 3D cutting is widely used as a flexible manual segmentation tool to extract medical data on regions of interest. A novel method for clipping 3D medical data is proposed to reveal the interior of volumetric data. The 3D cutting method retains or clips away selected voxels projected inside an arbitrary-shaped closed curve which is clipping geometry constructed by interactive tool to make cutting operation more flexible. Transformation between the world and screen coordinate frames is studied to project voxels of medical data onto the screen frame and avoid computing intersection of clipping geometry and volumetric data in 3D space. For facilitating the decision on whether the voxels should be retained, voxels through coordinate transformation are all projected onto a binary mask image on screen frame which the closed curve is also projected onto to conveniently obtain the voxels of intersection. The paper pays special attention to optimization algorithm of cutting process. The optimization algorithm that mixes octree with quad-tree decomposition is introduced to reduce computation complexity, save computation time, and match real time. The paper presents results obtained from raw and segmented medical volume datasets and the process time of cutting operation. PMID:25456145

  17. Study the Z-Plane Strip Capacitance

    SciTech Connect

    Parikh, H.; Swain, S.; /SLAC

    2005-12-15

    The BaBaR detector at the Stanford Linear Accelerator Center is currently undergoing an upgrade to improve its muon and neutral hadron detection system. The Resistive Plate Chambers (RPCs) that had been used till now have deteriorated in performance over the past few years and are being replaced by Limited Streamer Tube (LSTs). Each layer of the system consists of a set of up to 10 streamer tube modules which provide one coordinate ({phi} coordinate) and a single ''Z-plane'' which provides the Z coordinate of the hit. The large area Z-planes (up to 12m{sup 2}) are 1mm thick and contain 96 copper strips that detect the induced charge from avalanches created in the streamer tube wires. All the Z-planes needed for the upgrade have already been constructed, but only a third of the planes were installed last summer. After installing the 24 Z-planes last year, it was learned that 0.7% of the strips were dead when put inside the detector. This was mainly due to the delicate solder joint between the read-out cable and the strip, and since it is difficult to access or replace the Z-planes inside the detector, it is very important to perform various tests to make sure that the Z-planes will be efficient and effective in the long term. We measure the capacitance between the copper strips and the ground plane, and compare it to the theoretical value that we expect. Instead of measuring the capacitance channel by channel, which would be a very tedious job, we developed a more effective method of measuring the capacitance. Since all the Z-planes were built at SLAC, we also built a smaller 46 cm by 30 cm Z-plane with 12 strips just to see how they were constructed and to gain a better understanding about the solder joints.

  18. Automatic inspection system of surface defects on optical IR-CUT filter based on machine vision

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Yu, Feihong

    2014-04-01

    The paper presents an automatic surface defects inspection system for optical Infrared Cut-off (IR-CUT) filter, which is applied in all kinds of color cameras and video devices. The system involves illumination and imaging module, moving module, flipping module and machine vision algorithm. To highlight all the defected regions, the improved dark-field illumination technique is utilized in the imaging module. In order to accurately localize the region of optical IR-CUT filter in the captured image, stationary wavelet transform (SWT) is introduced to template matching algorithm. The introduction of SWT provides a more accurate estimate of the variances in the image and further facilitates the identification of the defected regions. The defects extraction method in this paper avoids the use of complicated learning process from a set of samples. Convexity theory is implemented on the algorithm of defects classification of edge crack. Experimental results on a variety of optical IR-CUT filter samples, including non-defective samples, samples with defects of stain, scratch and edge crack, have shown the efficiency (1.05 s per sample) and accuracy (96.44%) of the proposed system. Moreover, defects extraction performances of different filters are compared in this paper. The research and application of the system will greatly liberate the human workforce and inspire ideas to detect the defects of some other small optical elements.

  19. Portable propellant cutting assembly, and method of cutting propellant with assembly

    NASA Technical Reports Server (NTRS)

    Sharp, Roger A. (Inventor); Hoskins, Shawn W. (Inventor); Payne, Brett D. (Inventor)

    2002-01-01

    A propellant cutting assembly and method of using the assembly to cut samples of solid propellant in a repeatable and consistent manner is disclosed. The cutting assembly utilizes two parallel extension beams which are shorter than the diameter of a central bore of an annular solid propellant grain and can be loaded into the central bore. The assembly is equipped with retaining heads at its respective ends and an adjustment mechanism to position and wedge the assembly within the central bore. One end of the assembly is equipped with a cutting blade apparatus which can be extended beyond the end of the extension beams to cut into the solid propellant.

  20. Efficient Algorithm for Locating and Sizing Series Compensation Devices in Large Transmission Grids: Solutions and Applications (PART II)

    SciTech Connect

    Frolov, Vladimir; Backhaus, Scott N.; Chertkov, Michael

    2014-01-14

    In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~2700 nodes and ~3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polish grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements

  1. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: II. Solutions and applications

    SciTech Connect

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-01

    In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~ 2700 nodes and ~ 3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polish grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements.

  2. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: II. Solutions and applications

    NASA Astrophysics Data System (ADS)

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-01

    In a companion manuscript (Frolov et al 2014 New J. Phys. 16 art. no.) , we developed a novel optimization method for the placement, sizing, and operation of flexible alternating current transmission system (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide series compensation (SC) via modification of line inductance. In this sequel manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (˜2700 nodes and ˜3300 lines). The results from the 30-bus network are used to study the general properties of the solutions, including nonlocality and sparsity. The Polish grid is used to demonstrate the computational efficiency of the heuristics that leverage sequential linearization of power flow constraints, and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, we can use the algorithm to solve a Polish transmission grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (i) uniform load growth, (ii) multiple overloaded configurations, and (iii) sequential generator retirements.

  3. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: II. Solutions and applications

    DOE PAGESBeta

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-01

    In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~ 2700 nodes and ~ 3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polishmore » grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements.« less

  4. Numerical simulations of aerodynamic contribution of flows about a space-plane-type configuration

    NASA Technical Reports Server (NTRS)

    Matsushima, Kisa; Takanashi, Susume; Fujii, Kozo; Obayashi, Shigeru

    1987-01-01

    The slightly supersonic viscous flow about the space-plane under development at the National Aerospace Laboratory (NAL) in Japan was simulated numerically using the LU-ADI algorithm. The wind-tunnel testing for the same plane also was conducted with the computations in parallel. The main purpose of the simulation is to capture the phenomena which have a great deal of influence to the aerodynamic force and efficiency but is difficult to capture by experiments. It includes more accurate representation of vortical flows with high angles of attack of an aircraft. The space-plane shape geometry simulated is the simplified model of the real space-plane, which is a combination of a flat and slender body and a double-delta type wing. The comparison between experimental results and numerical ones will be done in the near future. It could be said that numerical results show the qualitatively reliable phenomena.

  5. The study on the image quality of varied line spacing plane grating by computer simulation

    NASA Astrophysics Data System (ADS)

    Sun, Shouqiang; Zhang, Weiping; Liu, Lei; Yang, Qingyi

    2014-11-01

    Varied line spacing plane gratings have the features of self-focusing , aberration-reduced and easy manufacturing ,which are widely applied in synchrotron radiation, plasma physics and space astronomy, and other fields. In the study of diffracting imaging , the optical path function is expanded into maclaurin series, aberrations are expressed by the coefficient of series, most of the aberration coefficients are similar and the category is more, can't directly reflects image quality in whole. The paper will study on diffraction imaging of the varied line spacing plane gratings by using computer simulation technology, for a method judging the image quality visibly. In this paper, light beam from some object points on the same object plane are analyzed and simulated by ray trace method , the evaluation function is set up, which can fully scale the image quality. In addition, based on the evaluation function, the best image plane is found by search algorithm .

  6. Phase unwrapping algorithms in laser propagation simulation

    NASA Astrophysics Data System (ADS)

    Du, Rui; Yang, Lijia

    2013-08-01

    Currently simulating on laser propagation in atmosphere usually need to deal with beam in strong turbulence, which may lose a part of information via Fourier Transform to simulate the transmission, makes the phase of beam as a 2-D array wrap by 2π . An effective unwrapping algorithm is needed for continuing result and faster calculation. The unwrapping algorithms in atmospheric propagation are similar to the unwrapping algorithm in radar or 3-D surface rebuilding, but not the same. In this article, three classic unwrapping algorithms: the block least squares (BLS), mask-cut (MCUT), and the Flynn's minimal discontinuity algorithm (FMD) are tried in wave-front reconstruction simulation. Each of those algorithms are tested 100 times in 6 same conditions, including low(64x64), medium(128x128), and high(256x256) resolution phase array, with and without noises. Compared the results, the conclusions are delivered as follows. The BLS-based algorithm is the fastest, and the result is acceptable in low resolution environment without noise. The MCUT are higher in accuracy, though they are slower with the array resolution increased, and it is sensitive to noise, resulted in large area errors. Flynn's algorithm has the better accuracy, and it occupies large memory in calculation. After all, the article delivered a new algorithm that based on Active on Vertex (AOV) Network, to build a logical graph to cut the search space then find minimal discontinuity solution. The AOV is faster than MCUT in dealing with high resolution phase arrays, and better accuracy as FMD that has been tested.

  7. Computations of Accumulated Deformations and Depletion of Plasticity Reserve Held by the Metal in the Surface Layer during Orthogonal Cutting

    NASA Astrophysics Data System (ADS)

    Blumenstein, V. Yu; Ferranti, A.

    2016-04-01

    The problem relating to the mechanics of orthogonal cutting with the deformation site, which is located within the contact area ahead of, below and behind the cutting tool was provided a solution. The above problem is crucial as it involves developing the mechanics of technological inheritance, which emphasizes the need for the operation-by-operation computations of the metal deformed state. The plane deformation (strain) model was adopted for the treatment with a cutter having a rounded cutting edge. Stresses, rates and deformations along the lines of current, which form the strengthened surface layer of the treated part, were computed. The patterns determining deformation accumulation and metal plasticity reserve depletion during orthogonal cutting were exposed.

  8. T-L Plane Abstraction-Based Energy-Efficient Real-Time Scheduling for Multi-Core Wireless Sensors.

    PubMed

    Kim, Youngmin; Lee, Ki-Seong; Pham, Ngoc-Son; Lee, Sun-Ro; Lee, Chan-Gun

    2016-01-01

    Energy efficiency is considered as a critical requirement for wireless sensor networks. As more wireless sensor nodes are equipped with multi-cores, there are emerging needs for energy-efficient real-time scheduling algorithms. The T-L plane-based scheme is known to be an optimal global scheduling technique for periodic real-time tasks on multi-cores. Unfortunately, there has been a scarcity of studies on extending T-L plane-based scheduling algorithms to exploit energy-saving techniques. In this paper, we propose a new T-L plane-based algorithm enabling energy-efficient real-time scheduling on multi-core sensor nodes with dynamic power management (DPM). Our approach addresses the overhead of processor mode transitions and reduces fragmentations of the idle time, which are inherent in T-L plane-based algorithms. Our experimental results show the effectiveness of the proposed algorithm compared to other energy-aware scheduling methods on T-L plane abstraction. PMID:27399722

  9. T-L Plane Abstraction-Based Energy-Efficient Real-Time Scheduling for Multi-Core Wireless Sensors

    PubMed Central

    Kim, Youngmin; Lee, Ki-Seong; Pham, Ngoc-Son; Lee, Sun-Ro; Lee, Chan-Gun

    2016-01-01

    Energy efficiency is considered as a critical requirement for wireless sensor networks. As more wireless sensor nodes are equipped with multi-cores, there are emerging needs for energy-efficient real-time scheduling algorithms. The T-L plane-based scheme is known to be an optimal global scheduling technique for periodic real-time tasks on multi-cores. Unfortunately, there has been a scarcity of studies on extending T-L plane-based scheduling algorithms to exploit energy-saving techniques. In this paper, we propose a new T-L plane-based algorithm enabling energy-efficient real-time scheduling on multi-core sensor nodes with dynamic power management (DPM). Our approach addresses the overhead of processor mode transitions and reduces fragmentations of the idle time, which are inherent in T-L plane-based algorithms. Our experimental results show the effectiveness of the proposed algorithm compared to other energy-aware scheduling methods on T-L plane abstraction. PMID:27399722

  10. Cytoplasm segmentation on cervical cell images using graph cut-based approach.

    PubMed

    Zhang, Ling; Kong, Hui; Chin, Chien Ting; Wang, Tianfu; Chen, Siping

    2014-01-01

    This paper proposes a method to segment the cytoplasm in cervical cell images using graph cut-based algorithm. First, the A* channel in CIE LAB color space is extracted for contrast enhancement. Then, in order to effectively extract cytoplasm boundaries when image histograms present non-bimodal distribution, Otsu multiple thresholding is performed on the contrast enhanced image to generate initial segments, based on which the segments are refined by the multi-way graph cut method. We use 21 cervical cell images with non-ideal imaging condition to evaluate cytoplasm segmentation performance. The proposed method achieved a 93% accuracy which outperformed state-of-the-art works. PMID:24212005

  11. Iterative graph cuts for image segmentation with a nonlinear statistical shape prior

    PubMed Central

    Chang, Joshua C.; Chou, Tom

    2013-01-01

    Shape-based regularization has proven to be a useful method for delineating objects within noisy images where one has prior knowledge of the shape of the targeted object. When a collection of possible shapes is available, the specification of a shape prior using kernel density estimation is a natural technique. Unfortunately, energy functionals arising from kernel density estimation are of a form that makes them impossible to directly minimize using efficient optimization algorithms such as graph cuts. Our main contribution is to show how one may recast the energy functional into a form that is minimizable iteratively and efficiently using graph cuts. PMID:24678141

  12. Mathematical simulation and optimization of cutting modes in turning of titanium alloy workpieces

    NASA Astrophysics Data System (ADS)

    Bogoljubova, M.; Afonasov, A.; Kozlov, V.; Sumtsova, O.

    2016-04-01

    A predictive modeling technique of optimal cutting modes in machining of workpieces made of titanium alloys, different from the well-known ones, is offered. The influence of various factors on the process of cutting for the purpose of defining optimal parameters of machining in accordance with certain effectiveness criteria is examined in the present paper. Mathematical models of optimization, algorithms and computer programmes, visual graphical forms presenting dependences of effectiveness criteria on the master schedule parameters have been worked out. Verification of mathematical models in laboratory and working conditions has been carried out.

  13. Improved autonomous star identification algorithm

    NASA Astrophysics Data System (ADS)

    Luo, Li-Yan; Xu, Lu-Ping; Zhang, Hua; Sun, Jing-Rong

    2015-06-01

    The log-polar transform (LPT) is introduced into the star identification because of its rotation invariance. An improved autonomous star identification algorithm is proposed in this paper to avoid the circular shift of the feature vector and to reduce the time consumed in the star identification algorithm using LPT. In the proposed algorithm, the star pattern of the same navigation star remains unchanged when the stellar image is rotated, which makes it able to reduce the star identification time. The logarithmic values of the plane distances between the navigation and its neighbor stars are adopted to structure the feature vector of the navigation star, which enhances the robustness of star identification. In addition, some efforts are made to make it able to find the identification result with fewer comparisons, instead of searching the whole feature database. The simulation results demonstrate that the proposed algorithm can effectively accelerate the star identification. Moreover, the recognition rate and robustness by the proposed algorithm are better than those by the LPT algorithm and the modified grid algorithm. Project supported by the National Natural Science Foundation of China (Grant Nos. 61172138 and 61401340), the Open Research Fund of the Academy of Satellite Application, China (Grant No. 2014_CXJJ-DH_12), the Fundamental Research Funds for the Central Universities, China (Grant Nos. JB141303 and 201413B), the Natural Science Basic Research Plan in Shaanxi Province, China (Grant No. 2013JQ8040), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130203120004), and the Xi’an Science and Technology Plan, China (Grant. No CXY1350(4)).

  14. Algorithms for skiascopy measurement automatization

    NASA Astrophysics Data System (ADS)

    Fomins, Sergejs; Trukša, Renārs; KrūmiĆa, Gunta

    2014-10-01

    Automatic dynamic infrared retinoscope was developed, which allows to run procedure at a much higher rate. Our system uses a USB image sensor with up to 180 Hz refresh rate equipped with a long focus objective and 850 nm infrared light emitting diode as light source. Two servo motors driven by microprocessor control the rotation of semitransparent mirror and motion of retinoscope chassis. Image of eye pupil reflex is captured via software and analyzed along the horizontal plane. Algorithm for automatic accommodative state analysis is developed based on the intensity changes of the fundus reflex.

  15. Plane Localization in 3-D Fetal Neurosonography for Longitudinal Analysis of the Developing Brain.

    PubMed

    Yaqub, Mohammad; Rueda, Sylvia; Kopuri, Anil; Melo, Pedro; Papageorghiou, A T; Sullivan, Peter B; McCormick, Kenneth; Noble, J Alison

    2016-07-01

    The parasagittal (PS) plane is a 2-D diagnostic plane used routinely in cranial ultrasonography of the neonatal brain. This paper develops a novel approach to find the PS plane in a 3-D fetal ultrasound scan to allow image-based biomarkers to be tracked from prebirth through the first weeks of postbirth life. We propose an accurate plane-finding solution based on regression forests (RF). The method initially localizes the fetal brain and its midline automatically. The midline on several axial slices is used to detect the midsagittal plane, which is used as a constraint in the proposed RF framework to detect the PS plane. The proposed learning algorithm guides the RF learning method in a novel way by: 1) using informative voxels and voxel informative strength as a weighting within the training stage objective function, and 2) introducing regularization of the RF by proposing a geometrical feature within the training stage. Results on clinical data indicate that the new automated method is more reproducible than manual plane finding obtained by two clinicians. PMID:26011873

  16. Application of iterative path revision technique for laser cutting with controlled fracture

    NASA Astrophysics Data System (ADS)

    Tsai, Chwan-Huei; Chen, Chien-Jen

    2004-01-01

    Laser cutting using the controlled fracture technique has great potential to be employed for the ceramic substrate machining. The heat produced on the surface of a ceramic substrate by the laser separates the substrate controllably along the moving path of the laser beam. Because the extension of the breaking frontier is lager than the movement of the laser spot, the actual fracture trajectory deviates from the desired trajectory when cutting a curve or cutting an asymmetrical straight line. To eliminate this deviation, the iterative learning control method is introduced to obtain the optimal laser beam movement path. The fracture contour image is grabbed by a CCD camera after laser cutting completion. A new image processing system is proposed to detect the deviation between the desired cutting path and the actual fracture trajectory. The laser-movement path for the next trial can then be determined according to the iterative path revision algorithm. The actual fracture trajectory converging to the desired cutting path is assured after a few path revisions. The experimental materials used in these experiments are alumina ceramics and the laser source is CO 2 laser. The proposed system can achieve a machining precision of about 0.1 mm.

  17. Estimation of the laser cutting operating cost by support vector regression methodology

    NASA Astrophysics Data System (ADS)

    Jović, Srđan; Radović, Aleksandar; Šarkoćević, Živče; Petković, Dalibor; Alizamir, Meysam

    2016-09-01

    Laser cutting is a popular manufacturing process utilized to cut various types of materials economically. The operating cost is affected by laser power, cutting speed, assist gas pressure, nozzle diameter and focus point position as well as the workpiece material. In this article, the process factors investigated were: laser power, cutting speed, air pressure and focal point position. The aim of this work is to relate the operating cost to the process parameters mentioned above. CO2 laser cutting of stainless steel of medical grade AISI316L has been investigated. The main goal was to analyze the operating cost through the laser power, cutting speed, air pressure, focal point position and material thickness. Since the laser operating cost is a complex, non-linear task, soft computing optimization algorithms can be used. Intelligent soft computing scheme support vector regression (SVR) was implemented. The performance of the proposed estimator was confirmed with the simulation results. The SVR results are then compared with artificial neural network and genetic programing. According to the results, a greater improvement in estimation accuracy can be achieved through the SVR compared to other soft computing methodologies. The new optimization methods benefit from the soft computing capabilities of global optimization and multiobjective optimization rather than choosing a starting point by trial and error and combining multiple criteria into a single criterion.

  18. Imaging, cutting, and collecting instrument and method

    DOEpatents

    Tench, Robert J.; Siekhaus, Wigbert J.; Balooch, Mehdi; Balhorn, Rodney L.; Allen, Michael J.

    1995-01-01

    Instrumentation and techniques to image small objects, such as but not limited to individual human chromosomes, with nanometer resolution, to cut-off identified parts of such objects, to move around and manipulate such cut-off parts on the substrate on which they are being imaged to predetermined locations on the substrate, and to remove the cut-off parts from the substrate. This is accomplished using an atomic force microscope (AFM) and by modification of the conventional cantilever stylus assembly of an AFM, such that plural cantilevers are used with either sharp-tips or knife-edges thereon. In addition, the invention can be utilized for measuring hardness of materials.

  19. Laser cutting with chemical reaction assist

    DOEpatents

    Gettemy, Donald J.

    1992-01-01

    A method for cutting with a laser beam where an oxygen-hydrocarbon reaction is used to provide auxiliary energy to a metal workpiece to supplement the energy supplied by the laser. Oxygen is supplied to the laser focus point on the workpiece by a nozzle through which the laser beam also passes. A liquid hydrocarbon is supplied by coating the workpiece along the cutting path with the hydrocarbon prior to laser irradiation or by spraying a stream of hydrocarbon through a nozzle aimed at a point on the cutting path which is just ahead of the focus point during irradiation.

  20. Laser cutting with chemical reaction assist

    DOEpatents

    Gettemy, D.J.

    1992-11-17

    A method is described for cutting with a laser beam where an oxygen-hydrocarbon reaction is used to provide auxiliary energy to a metal workpiece to supplement the energy supplied by the laser. Oxygen is supplied to the laser focus point on the workpiece by a nozzle through which the laser beam also passes. A liquid hydrocarbon is supplied by coating the workpiece along the cutting path with the hydrocarbon prior to laser irradiation or by spraying a stream of hydrocarbon through a nozzle aimed at a point on the cutting path which is just ahead of the focus point during irradiation. 1 figure.

  1. Ultrasonic technology improves drill cuttings disposal

    SciTech Connect

    Avern, N.; Copercini, A.

    1997-07-01

    Advancements are being made by employing ultrasonics for onsite cuttings size reduction for slurrification prior to disposal. The size reduction proficiency of this new ultrasonics slurrification system as a medium to reduce the particle size of drill cuttings presents operators with a system that can enhance existing disposal techniques. This article presents results from a recent field trial, where ultrasonic processors were used to Agip (UK) Limited to reduce the particle size of drill cuttings prior to disposal into the water column and natural dispersement.

  2. Laser cutting with chemical reaction assist

    SciTech Connect

    Gettemy, D.J.

    1991-04-08

    This invention is comprised of a method for cutting with a laser beam where an oxygen-hydrocarbon reaction is used to provide auxiliary energy to a metal workpiece to supplement the energy supplied by the laser. Oxygen is supplied to the laser focus point on the workpiece by a nozzle through which the laser beam also passes. A liquid hydrocarbon is supplied by coating the workpiece along the cutting path with the hydrocarbon prior to laser irradiation or by spraying a stream of hydrocarbon through a nozzle aimed at a point on the cutting path which is just ahead of the focus point during irradiation.

  3. a Min-Cut Based Filter for Airborne LIDAR Data

    NASA Astrophysics Data System (ADS)

    Ural, Serkan; Shan, Jie

    2016-06-01

    LiDAR (Light Detection and Ranging) is a routinely employed technology as a 3-D data collection technique for topographic mapping. Conventional workflows for analyzing LiDAR data require the ground to be determined prior to extracting other features of interest. Filtering the terrain points is one of the fundamental processes to acquire higher-level information from unstructured LiDAR point data. There are many ground-filtering algorithms in literature, spanning several broad categories regarding their strategies. Most of the earlier algorithms examine only the local characteristics of the points or grids, such as the slope, and elevation discontinuities. Since considering only the local properties restricts the filtering performance due to the complexity of the terrain and the features, some recent methods utilize global properties of the terrain as well. This paper presents a new ground filtering method, Min-cut Based Filtering (MBF), which takes both local and global properties of the points into account. MBF considers ground filtering as a labeling task. First, an energy function is designed on a graph, where LiDAR points are considered as the nodes on the graph that are connected to each other as well as to two auxiliary nodes representing ground and off-ground labels. The graph is constructed such that the data costs are assigned to the edges connecting the points to the auxiliary nodes, and the smoothness costs to the edges between points. Data and smoothness terms of the energy function are formulated using point elevations and approximate ground information. The data term conducts the likelihood of the points being ground or off-ground while the smoothness term enforces spatial coherence between neighboring points. The energy function is optimized by finding the minimum-cut on the graph via the alpha-expansion algorithm. The resulting graph-cut provides the labeling of the point cloud as ground and off-ground points. Evaluation of the proposed method on

  4. A new frame-based registration algorithm.

    PubMed

    Yan, C H; Whalen, R T; Beaupre, G S; Sumanaweera, T S; Yen, S Y; Napel, S

    1998-01-01

    This paper presents a new algorithm for frame registration. Our algorithm requires only that the frame be comprised of straight rods, as opposed to the N structures or an accurate frame model required by existing algorithms. The algorithm utilizes the full 3D information in the frame as well as a least squares weighting scheme to achieve highly accurate registration. We use simulated CT data to assess the accuracy of our algorithm. We compare the performance of the proposed algorithm to two commonly used algorithms. Simulation results show that the proposed algorithm is comparable to the best existing techniques with knowledge of the exact mathematical frame model. For CT data corrupted with an unknown in-plane rotation or translation, the proposed technique is also comparable to the best existing techniques. However, in situations where there is a discrepancy of more than 2 mm (0.7% of the frame dimension) between the frame and the mathematical model, the proposed technique is significantly better (p < or = 0.05) than the existing techniques. The proposed algorithm can be applied to any existing frame without modification. It provides better registration accuracy and is robust against model mis-match. It allows greater flexibility on the frame structure. Lastly, it reduces the frame construction cost as adherence to a concise model is not required. PMID:9472834

  5. A new frame-based registration algorithm

    NASA Technical Reports Server (NTRS)

    Yan, C. H.; Whalen, R. T.; Beaupre, G. S.; Sumanaweera, T. S.; Yen, S. Y.; Napel, S.

    1998-01-01

    This paper presents a new algorithm for frame registration. Our algorithm requires only that the frame be comprised of straight rods, as opposed to the N structures or an accurate frame model required by existing algorithms. The algorithm utilizes the full 3D information in the frame as well as a least squares weighting scheme to achieve highly accurate registration. We use simulated CT data to assess the accuracy of our algorithm. We compare the performance of the proposed algorithm to two commonly used algorithms. Simulation results show that the proposed algorithm is comparable to the best existing techniques with knowledge of the exact mathematical frame model. For CT data corrupted with an unknown in-plane rotation or translation, the proposed technique is also comparable to the best existing techniques. However, in situations where there is a discrepancy of more than 2 mm (0.7% of the frame dimension) between the frame and the mathematical model, the proposed technique is significantly better (p < or = 0.05) than the existing techniques. The proposed algorithm can be applied to any existing frame without modification. It provides better registration accuracy and is robust against model mis-match. It allows greater flexibility on the frame structure. Lastly, it reduces the frame construction cost as adherence to a concise model is not required.

  6. Algorithms for physical segregation of coal

    NASA Astrophysics Data System (ADS)

    Ganguli, Rajive

    The capability for on-line measurement of the quality characteristics of conveyed coal now enables mine operators to take advantage of the inherent heterogeneity of those streams and split them into wash and no-wash stocks. Relative to processing the entire stream, this reduces the amount of coal that must be washed at the mine and thereby reduces processing costs, recovery losses, and refuse generation levels. In this dissertation, two classes of segregation algorithms, using time series models and moving windows are developed and demonstrated using field and simulated data. In all of the developed segregation algorithms, a "cut-off" ash value was computed for coal scanned on the running conveyor belt by the ash analyzer. It determined if the coal was sent to the wash pile or to the nowash pile. Forecasts from time series models, at various lead times ahead, were used in one class of the developed algorithms, to determine the cut-off ash levels. The time series models were updated from time to time to reflect changes in process. Statistical Process Control (SPC) techniques were used to determine if an update was necessary at a given time. When an update was deemed necessary, optimization techniques were used to determine the next best set of model parameters. In the other class of segregation algorithms, "few" of the immediate past observations were used to determine the cut-off ash value. These "few" observations were called the window width . The window width was kept constant in some variants of this class of algorithms. The other variants of this class were an improvement over the fixed window width algorithms. Here, the window widths were varied rather than kept constant. In these cases, SPC was used to determine the window width at any instant. Statistics of the empirical distribution and the normal distribution were used in computation of the cut-off ash value in all the variants of this class of algorithms. The good performance of the developed algorithms

  7. Laser Cutting of Leather: Tool for Industry or Designers?

    NASA Astrophysics Data System (ADS)

    Stepanov, Alexander; Manninen, Matti; Pärnänen, Inni; Hirvimäki, Marika; Salminen, Antti

    Currently technologies which are applied for leather cutting include slitting knifes, die press techniques and manual cutting. Use of laser technology has grown significantly during recent years due to number of advantages over conventional cutting methods; flexibility, high production speed, possibility to cut complex geometries, easier cutting of customized parts, and less leftovers of leather makes laser cutting more and more economically attractive to apply for leather cutting. Laser technology provides advantages in cutting complex geometries, stable cutting quality and possibility to utilize leather material in economically best way. Constant quality is important in industrial processes and laser technology fulfills this requirement: properly chosen laser cutting parameters provides identical cuts. Additionally, laser technology is very flexible in terms of geometries: complex geometries, individual designs, prototypes and small scale products can be manufactured by laser cutting. Variety of products, which needed to be cut in small volumes, is also the application where laser cutting can be more beneficial due to possibility to change production from one product to another only by changing geometry without a need to change cutting tool. Disadvantages of laser processing include high initial investment costs and some running costs due to maintenance and required gas supply for the laser. Higher level of operator's expertise is required due to more complicated machinery in case of laser cutting. This study investigates advantages and disadvantages of laser cutting in different areas of application and provides comparison between laser cutting and mechanical cutting of leather.

  8. Efficient algorithms for proximity problems

    SciTech Connect

    Wee, Y.C.

    1989-01-01

    Computational geometry is currently a very active area of research in computer science because of its applications to VLSI design, database retrieval, robotics, pattern recognition, etc. The author studies a number of proximity problems which are fundamental in computational geometry. Optimal or improved sequential and parallel algorithms for these problems are presented. Along the way, some relations among the proximity problems are also established. Chapter 2 presents an O(N log{sup 2} N) time divide-and-conquer algorithm for solving the all pairs geographic nearest neighbors problem (GNN) for a set of N sites in the plane under any L{sub p} metric. Chapter 3 presents an O(N log N) divide-and-conquer algorithm for computing the angle restricted Voronoi diagram for a set of N sites in the plane. Chapter 4 introduces a new data structure for the dynamic version of GNN. Chapter 5 defines a new formalism called the quasi-valid range aggregation. This formalism leads to a new and simple method for reducing non-range query-like problems to range queries and often to orthogonal range queries, with immediate applications to the attracted neighbor and the planar all-pairs nearest neighbors problem. Chapter 6 introduces a new approach for the construction of the Voronoi diagram. Using this approach, we design an O(log N) time O (N) processor algorithm for constructing the Voronoi diagram with L{sub 1} and L. metrics on a CREW PRAM machine. Even though the GNN and the Delaunay triangulation (DT) do not have an inclusion relation, we show, using some range type queries, how to efficiently construct DT from the GNN relations over a constant number of angular ranges.

  9. Climate science hit by job cuts

    NASA Astrophysics Data System (ADS)

    Randall, Ian

    2016-03-01

    Climate researchers in Australia are bracing themselves for heavy job cuts as the country's national scientific agency - the Commonwealth Scientific and Industrial Research Organisation (CSIRO) - said last month it will reprioritize towards innovation.

  10. Ribbon cutting opens new ELV offices

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Center Director Roy Bridges welcomes the audience to a ribbon- cutting ceremony at the E&O Building at KSC. Home for NASA's unmanned missions since 1964, the building has been renovated to house the Expendable Launch Vehicle Program.

  11. Cutting single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Ziegler, Kirk J.; Gu, Zhenning; Shaver, Jonah; Chen, Zheyi; Flor, Erica L.; Schmidt, Daniel J.; Chan, Candace; Hauge, Robert H.; Smalley, Richard E.

    2005-07-01

    A two-step process is utilized for cutting single-walled carbon nanotubes (SWNTs). The first step requires the breakage of carbon-carbon bonds in the lattice while the second step is aimed at etching at these damage sites to create short, cut nanotubes. To achieve monodisperse lengths from any cutting strategy requires control of both steps. Room-temperature piranha and ammonium persulfate solutions have shown the ability to exploit the damage sites and etch SWNTs in a controlled manner. Despite the aggressive nature of these oxidizing solutions, the etch rate for SWNTs is relatively slow and almost no new sidewall damage is introduced. Carbon-carbon bond breakage can be introduced through fluorination to ~C2F, and subsequent etching using piranha solutions has been shown to be very effective in cutting nanotubes. The final average length of the nanotubes is approximately 100 nm with carbon yields as high as 70-80%.

  12. Hydro Impact Basin Ribbon-Cutting Ceremony

    NASA Video Gallery

    August 9, 2011 -- Ribbon-cutting ceremony for the Hydro Impact Basin at NASA's Langley Research Center in Hampton, Va. The HIB expands NASA's capability to test and certify future spacecraft for wa...

  13. Threaded pilot insures cutting tool alignment

    NASA Technical Reports Server (NTRS)

    Goldman, R.; Schneider, W. E.

    1966-01-01

    Threaded pilot allows machining of a port component, or boss, after the reciprocating hole has been threaded. It is used to align cutting surfaces with the boss threads, thus insuring precision alignment.

  14. Freon, T-B1 cutting fluid

    NASA Technical Reports Server (NTRS)

    Peters, R. L.

    1969-01-01

    Improved cutting fluid completely controls the heat generated from machining operations, thus providing longer tool life. Fluid is especially useful in the working of plastics and replaces less efficient contaminating oils.

  15. 8 ways to cut health care costs

    MedlinePlus

    ... ency/patientinstructions/000870.htm 8 ways to cut health care costs To use the sharing features on this page, please enable JavaScript. The cost of health care continues to rise. That is why it helps ...

  16. Automated Cell-Cutting for Cell Cloning

    NASA Astrophysics Data System (ADS)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  17. FTA Basic Event & Cut Set Ranking.

    Energy Science and Technology Software Center (ESTSC)

    1999-05-04

    Version 00 IMPORTANCE computes various measures of probabilistic importance of basic events and minimal cut sets to a fault tree or reliability network diagram. The minimal cut sets, the failure rates and the fault duration times (i.e., the repair times) of all basic events contained in the minimal cut sets are supplied as input data. The failure and repair distributions are assumed to be exponential. IMPORTANCE, a quantitative evaluation code, then determines the probability ofmore » the top event and computes the importance of minimal cut sets and basic events by a numerical ranking. Two measures are computed. The first describes system behavior at one point in time; the second describes sequences of failures that cause the system to fail in time. All measures are computed assuming statistical independence of basic events. In addition, system unavailability and expected number of system failures are computed by the code.« less

  18. Throat-cutting of accidental origin.

    PubMed

    Demirci, Serafettin; Dogan, Kamil Hakan; Gunaydin, Gursel

    2008-07-01

    Incised wounds of the neck can be accidental, homicidal, or suicidal. In this paper, a death case has been presented where a spinning circular saw of a cutting machine in a workshop came off its place and cut the throat of a 30-year-old male who was operating the machine. There was an incision (15 cm x 5 cm) that began in the middle of the neck down the thyroid cartilage, extended horizontally to the left of the neck and ended on the outer part of the neck in the outer left side of m. trapezius. Death occurred because of exsanguination caused by the cutting of carotis artery and jugular vein. In the case we presented, although the cut in the neck initially suggested homicide, it was found to have occurred as a result of an accident after the autopsy and death scene investigation. PMID:18489556

  19. Chevron cutting: Experiment with new runway mixtures

    NASA Technical Reports Server (NTRS)

    Tyran, K. (Compiler)

    1978-01-01

    Chevron cutting is shown to occur in different forms depending on the type of tire and the rubber on the running surface. Hardest wear is shown by the main tires of the B-747. Four defects occurred, in the form of two rip separation and two breakouts of the running surface. Tires capped by Thompson are more affected than any of the other rubber-capping fabrics. For Thompson tires, Chevron Cutting is greatly reduced with a fiberglass-rubber mixture. For Goodyear tires, it is eliminated with spiral wrap rubbercapping; resistance to damages through cuts seems to be more positive for Goodyear tires. For Mader tires, the extent of Chevron Cutting is generally smaller than for Thompson cappings.

  20. Flu Shot Might Cut Stillbirth Risk

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_158080.html Flu Shot Might Cut Stillbirth Risk Australian researchers find ... THURSDAY, March 31, 2016 (HealthDay News) -- A seasonal flu shot may reduce a pregnant woman's risk of ...

  1. French academy cries out over swingeing cuts

    NASA Astrophysics Data System (ADS)

    Dumé, Belle

    2014-02-01

    The French Academy of Sciences has issued what it calls a "cry of alarm" denouncing heavy cuts to the 2014 budget for the National Research Agency (ANR), which was set up in 2005 to fund project-based research.

  2. 33 CFR 117.161 - Honker Cut.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.161 Honker Cut. The draw of the San Joaquin... signal if at least 12 hours notice is given to the San Joaquin County Department of Public Works...

  3. 33 CFR 117.161 - Honker Cut.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.161 Honker Cut. The draw of the San Joaquin... signal if at least 12 hours notice is given to the San Joaquin County Department of Public Works...

  4. 33 CFR 117.143 - Bishop Cut.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin... hours notice is given to the San Joaquin County Department of Public Works at Stockton....

  5. 33 CFR 117.161 - Honker Cut.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.161 Honker Cut. The draw of the San Joaquin... signal if at least 12 hours notice is given to the San Joaquin County Department of Public Works...

  6. 33 CFR 117.161 - Honker Cut.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.161 Honker Cut. The draw of the San Joaquin... signal if at least 12 hours notice is given to the San Joaquin County Department of Public Works...

  7. 33 CFR 117.143 - Bishop Cut.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin... hours notice is given to the San Joaquin County Department of Public Works at Stockton....

  8. 33 CFR 117.143 - Bishop Cut.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin... hours notice is given to the San Joaquin County Department of Public Works at Stockton....

  9. 33 CFR 117.143 - Bishop Cut.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin... hours notice is given to the San Joaquin County Department of Public Works at Stockton....

  10. Study made of explosive cutting in simulated space environments

    NASA Technical Reports Server (NTRS)

    Coleman, E. R.; Hamilton, L. O.

    1967-01-01

    Study indicates the feasibility of explosive cutting and establishes techniques applicable to in-space cutting operations. Results show no degradation of the explosive and that work hardening of the target material is limited to the cut edge.

  11. Material cutting, shaping, and forming: A compilation

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Information is presented concerning cutting, shaping, and forming of materials, and the equipment and techniques required for utilizing these materials. The use of molds, electrical fields, and mechanical devices are related to forming materials. Material cutting methods by devices including borers and slicers are presented along with chemical techniques. Shaping and fabrication techniques are described for tubing, honeycomb panels, and ceramic structures. The characteristics of the materials are described. Patent information is included.

  12. Cutting Symmetrical Recesses In Soft Ceramic Tiles

    NASA Technical Reports Server (NTRS)

    Nesotas, Tony C.; Tyler, Brent

    1989-01-01

    Simple tool cuts hemispherical recesses in soft ceramic tiles. Designed to expose wires of thermocouples embedded in tiles without damaging leads. Creates neat, precise holes around wires. End mill includes axial hole to accommodate thermocouple wires embedded in material to be cut. Wires pass into hole without being bent or broken. Dimensions in inches. Used in place of such tools as dental picks, tweezers, spatulas, and putty knives.

  13. Attitude analysis in Flatland: The plane truth

    NASA Technical Reports Server (NTRS)

    Shuster, Malcolm D.

    1993-01-01

    Many results in attitude analysis are still meaningful when the attitude is restricted to rotations about a single axis. Such a picture corresponds to attitude analysis in the Euclidean plane. The present report formalizes the representation of attitude in the plane and applies it to some well-known problems. In particular, we study the connection of the 'additive' and 'multiplicative' formulations of the differential corrector for the quaternion in its two-dimensional setting.

  14. Learning-based scan plane identification from fetal head ultrasound images

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoming; Annangi, Pavan; Gupta, Mithun; Yu, Bing; Padfield, Dirk; Banerjee, Jyotirmoy; Krishnan, Kajoli

    2012-03-01

    Acquisition of a clinically acceptable scan plane is a pre-requisite for ultrasonic measurement of anatomical features from B-mode images. In obstetric ultrasound, measurement of gestational age predictors, such as biparietal diameter and head circumference, is performed at the level of the thalami and cavum septum pelucidi. In an accurate scan plane, the head can be modeled as an ellipse, the thalami looks like a butterfly, the cavum appears like an empty box and the falx is a straight line along the major axis of a symmetric ellipse inclined either parallel to or at small angles to the probe surface. Arriving at the correct probe placement on the mother's belly to obtain an accurate scan plane is a task of considerable challenge especially for a new user of ultrasound. In this work, we present a novel automated learning-based algorithm to identify an acceptable fetal head scan plane. We divide the problem into cranium detection and a template matching to capture the composite "butterfly" structure present inside the head, which mimics the visual cues used by an expert. The algorithm uses the stateof- the-art Active Appearance Models techniques from the image processing and computer vision literature and tie them to presence or absence of the inclusions within the head to automatically compute a score to represent the goodness of a scan plane. This automated technique can be potentially used to train and aid new users of ultrasound.

  15. Autofocusing method for tilted image plane detection in digital holographic microscopy

    NASA Astrophysics Data System (ADS)

    Kostencka, Julianna; Kozacki, Tomasz; Liżewski, Kamil

    2013-06-01

    A rapid autofocusing technique is a fundamental element for a vast range of applications of digital holography. In this paper we propose a new autofocusing method that permits to detect a tilted optimal focus plane. The method is based on estimation of focusing condition of the optical field by evaluating the sharpness in its amplitude distribution. The developed algorithm is fully automated. It consists of two major steps, first the rotation axis is localized from the map of local sharpness and then the angular orientation of the image plane is derived by maximizing the focus of optical fields reconstructed in many subsequent tilted planes. In our study six image sharpness quantification methods are investigated and the numerical propagation between inclined planes is performed with an efficient band limited angular spectrum algorithm. The utility of the proposed method for autofocusing to a tilted image plane is experimentally confirmed in a digital holographic microscopy setup by carrying out a successful reconstruction of holograms of the exemplary amplitude (the 1951 USAF positive target) and phase (a matrix of microlenses) objects.

  16. Artificial Intelligence Based Selection of Optimal Cutting Tool and Process Parameters for Effective Turning and Milling Operations

    NASA Astrophysics Data System (ADS)

    Saranya, Kunaparaju; John Rozario Jegaraj, J.; Ramesh Kumar, Katta; Venkateshwara Rao, Ghanta

    2016-06-01

    With the increased trend in automation of modern manufacturing industry, the human intervention in routine, repetitive and data specific activities of manufacturing is greatly reduced. In this paper, an attempt has been made to reduce the human intervention in selection of optimal cutting tool and process parameters for metal cutting applications, using Artificial Intelligence techniques. Generally, the selection of appropriate cutting tool and parameters in metal cutting is carried out by experienced technician/cutting tool expert based on his knowledge base or extensive search from huge cutting tool database. The present proposed approach replaces the existing practice of physical search for tools from the databooks/tool catalogues with intelligent knowledge-based selection system. This system employs artificial intelligence based techniques such as artificial neural networks, fuzzy logic and genetic algorithm for decision making and optimization. This intelligence based optimal tool selection strategy is developed using Mathworks Matlab Version 7.11.0 and implemented. The cutting tool database was obtained from the tool catalogues of different tool manufacturers. This paper discusses in detail, the methodology and strategies employed for selection of appropriate cutting tool and optimization of process parameters based on multi-objective optimization criteria considering material removal rate, tool life and tool cost.

  17. Quantum Max-flow/Min-cut

    NASA Astrophysics Data System (ADS)

    Cui, Shawn X.; Freedman, Michael H.; Sattath, Or; Stong, Richard; Minton, Greg

    2016-06-01

    The classical max-flow min-cut theorem describes transport through certain idealized classical networks. We consider the quantum analog for tensor networks. By associating an integral capacity to each edge and a tensor to each vertex in a flow network, we can also interpret it as a tensor network and, more specifically, as a linear map from the input space to the output space. The quantum max-flow is defined to be the maximal rank of this linear map over all choices of tensors. The quantum min-cut is defined to be the minimum product of the capacities of edges over all cuts of the tensor network. We show that unlike the classical case, the quantum max-flow=min-cut conjecture is not true in general. Under certain conditions, e.g., when the capacity on each edge is some power of a fixed integer, the quantum max-flow is proved to equal the quantum min-cut. However, concrete examples are also provided where the equality does not hold. We also found connections of quantum max-flow/min-cut with entropy of entanglement and the quantum satisfiability problem. We speculate that the phenomena revealed may be of interest both in spin systems in condensed matter and in quantum gravity.

  18. Demonstrating diamond wire cutting of the TFTR

    SciTech Connect

    Rule, K.; Perry, E.; Larson, S.; Viola, M.

    2000-02-24

    The Tokamak Fusion Test Reactor (TFTR) ceased operation in April 1997 and decommissioning commenced in October 1999. The deuterium-tritium fusion experiments resulted in contaminating the vacuum vessel with tritium and activating the materials with 14 Mev neutrons. The total tritium content within the vessel is in excess of 7,000 Curies while dose rates approach 50 mRem/hr. These radiological hazards along with the size of the Tokamak (100 cubic meters) present a unique and challenging task for dismantling. Plasma arc cutting is the current baseline technology for the dismantlement of fission reactors. This technology is typically used because of its faster cutting times. Alternatively, an innovative approach for dismantlement of the TFTR is the use of diamond wire cutting technology. Recent improvements in diamond wire technology have allowed the cutting of carbon steel components such as pipe, plate, and tube bundles in heat exchangers. Some expected benefits of this technology include: significantly reduction in airborne contaminates, reduced personnel exposure, a reduced risk of spread of tritium contamination, and reduced overall costs as compared to using plasma arc cutting. This paper will provide detailed results of the diamond wire cutting demonstration that was completed in September of 1999, on a mock-up of this complex reactor. The results will identify cost, safety, industrial and engineering parameters, and the related performance of each situation.

  19. Deep plane facelifting for facial rejuvenation.

    PubMed

    Gordon, Neil; Adam, Stewart

    2014-08-01

    The purpose of this article is to provide the facial plastic surgeon with anatomical and embryologic evidence to support the use of the deep plane technique for optimal treatment of facial aging. A detailed description of the procedure is provided to allow safe and consistent performance. Insights into anatomical landmarks, technical nuances, and alternative approaches for facial variations are presented. The following points will be further elucidated in the article. The platysma muscle/submuscular aponeurotic system/galea are the continuous superficial cervical fascia encompassing the majority of facial fat, and this superficial soft tissue envelope is poorly anchored to the face. The deep cervical fascia binds the structural aspects of the face and covers the facial nerve and buccal fat pad. Facial aging is mainly due to gravity's long-term effects on the superficial soft tissue envelope, with more subtle effects on the deeper structural compartments. The deep plane is the embryologic cleavage plane between these fascial layers, and is the logical place for facial dissection. The deep plane allows access to the buccal fat pad for treatment of jowling. Soft tissue mobilization is maximized in deep plane dissections and requires careful hairline planning. Flap advancement creates tension only at the fascia level allowing natural, tension-free skin closure, and long-lasting outcomes. The deep plane advancement flap is well vascularized and resistant to complications. PMID:25076447

  20. Wide bandsaw blade under cutting conditions. Part III: Stability of a plate moving in its plane while subjected to non-conservative cutting forces

    NASA Astrophysics Data System (ADS)

    Lengoc, L.; McCallion, H.

    1995-09-01

    This study provides yet another possible mechanism for instability of bandsaw blades during sawing, namely dynamic instability of a moving plate when subjected to non-conservative tangential edge loading. In previous publications, the effect of non-conservative edge loading has been neglected; only the divergent buckling and the parametric instability have been considered as causes of unstable bandsaw blade motion. However, the non-conservative loading due to sawing can excite a flutter-type instability, similar to flutter in aeroplane wings. The extended Galerkin method is used to discretize the equation of motion, and a non-self-adjoint eigenvalue solver is employed to find the solutions.

  1. Metal cutting analogy for establishing Friction Stir Welding process parameters

    NASA Astrophysics Data System (ADS)

    Stafford, Sylvester Allen

    A friction stir weld (FSW) is a solid state joining operation whose processing parameters are currently determined by lengthy trial and error methods. To implement FSWing rapidly in various applications will require an approach for predicting process parameters based on the physics of the process. Based on hot working conditions for metals, a kinematic model has been proposed for calculating the shear strain and shear strain rates during the FSW process, validation of the proposed model with direct measuring is difficult however. Since the shear strain and shear strain rates predicted for the FSW process, are similar to those predicted in metal cutting, validation of the FSW algorithms with microstructural studies of metal chips may be possible leading to the ability to predict FSW processing parameters.

  2. Plane wave transport method for low symmetry lattices and its application

    SciTech Connect

    Srivastava, Manoj K; Wang, Yan; Zhang, Xiaoguang; Nicholson, Don M; Cheng, Hai-Ping

    2012-01-01

    The existing first-principles plane wave transport method implementation \\cite{,choi-1,qe} has the limitation that it only allows transport directions along lattice vectors perpendicular to the basal plane formed by two other lattice vectors. We generalize the algorithm to low symmetry, nonorthogonal lattices thus allowing solution to problems in which the transport direction is not along any lattice vectors. As an application, we calculate the transmission and reflection coefficients, and determine interface resistance of various grain boundaries in crystalline copper.

  3. Reconstruction of unbroken vasculature of mouse by varying the slope of the scan plane in MRI

    NASA Astrophysics Data System (ADS)

    Maltseva, S.; Cherevko, A.; Khe, A.; Akulov, A.; Savelov, A.; Tulupov, A.; Derevtsov, E.; Moshkin, M.; Chupakhin, A.

    2016-02-01

    Reconstruction of vascular net of small laboratory animals from MRI data is associated with some problems. This paper proposes a method of MRI data processing which allows to eliminate the fragmentation of reconstructed vascular net. Problem of vessels fragmentation occurs in the case when vessels are parallel to the scanning plane. Our approach is based on multiple scanning, object under consideration is probed by several sets of parallel planes. The algorithm is applied to real MRI data of small laboratory animals and shows good results.

  4. Signal processing and compensation electronics for junction field-effect transistor /JFET/ focal plane arrays

    NASA Astrophysics Data System (ADS)

    Wittig, K. R.

    1982-06-01

    A signal processing system has been designed and constructed for a pyroelectric infrared area detector which uses a matrix-addressable JFET array for readout and for on-focal plane preamplification. The system compensates for all offset and gain nonuniformities in and after the array. Both compensations are performed in real time at standard television rates, so that changes in the response characteristics of the array are automatically corrected for. Two-point compensation is achieved without the need for two separate temperature references. The focal plane circuitry used to read out the array, the offset and gain compensation algorithms, the architecture of the signal processor, and the system hardware are described.

  5. Min-cut segmentation of cursive handwriting in tabular documents

    NASA Astrophysics Data System (ADS)

    Davis, Brian L.; Barrett, William A.; Swingle, Scott D.

    2015-01-01

    Handwritten tabular documents, such as census, birth, death and marriage records, contain a wealth of information vital to genealogical and related research. Much work has been done in segmenting freeform handwriting, however, segmentation of cursive handwriting in tabular documents is still an unsolved problem. Tabular documents present unique segmentation challenges caused by handwriting overlapping cell-boundaries and other words, both horizontally and vertically, as "ascenders" and "descenders" overlap into adjacent cells. This paper presents a method for segmenting handwriting in tabular documents using a min-cut/max-flow algorithm on a graph formed from a distance map and connected components of handwriting. Specifically, we focus on line, word and first letter segmentation. Additionally, we include the angles of strokes of the handwriting as a third dimension to our graph to enable the resulting segments to share pixels of overlapping letters. Word segmentation accuracy is 89.5% evaluating lines of the data set used in the ICDAR2013 Handwriting Segmentation Contest. Accuracy is 92.6% for a specific application of segmenting first and last names from noisy census records. Accuracy for segmenting lines of names from noisy census records is 80.7%. The 3D graph cutting shows promise in segmenting overlapping letters, although highly convoluted or overlapping handwriting remains an ongoing challenge.

  6. Ventilating the box cut of a two-pass 40-ft extended cut

    SciTech Connect

    Thimons, E.D.; Taylor, C.D.; Zimmer, J.A.

    1999-07-01

    On a continuous miner coal face methane concentrations are affected by the quantity of fresh intake air reaching the face. When mining the box cut on a 12.2-m (40-ft) two-pass extended cut face, the continuous miner is always at the point of deepest penetration, and operation of the machine-mounted dust scrubber and water spray system improve the flow of fresh air to the end of the box cut. However, when the continuous miner leaves the box cut to begin cutting the 40-ft slab, little is known about how much ventilation air reaches the end of the box cut. The Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health conducted a full-scale study to answer this question. Tests were run to determine how much ventilation air reaches the end of the box cut with the continuous miner at three locations in the 40-ft two-pass extended cut mining sequence; at the end of the 40-ft box cut, at the start of the 40-ft slab cut, and 6.1 m (20 ft) into the slab cut. During these tests, methane gas was uniformly released at the end of the 40-ft box cut. Methane concentrations measured 0.3 m (1 ft) from the roof and face of the box cut were used to estimate face airflow quantities. Fresh airflow rates of 1.89 and 4.72 m{sup 3}/sec (4,000 and 10,000 cfm), scrubber flow rates of 0, 4,000 and 10,000 cfm, water spray pressures of 0 and 827 kPa (0 and 120 psi), and a blowing curtain setback position of 15.2 m (50 ft) were used during these tests. To improve ventilation to the end of the 40-ft box cut when the continuous miner was staging the 40-ft slab cut and 20 ft into the slab cut, the blowing curtain was advanced from its 50-ft setback to locations 40-ft and then 8.5 m (28 ft) from the face.

  7. Algorithmic chemistry

    SciTech Connect

    Fontana, W.

    1990-12-13

    In this paper complex adaptive systems are defined by a self- referential loop in which objects encode functions that act back on these objects. A model for this loop is presented. It uses a simple recursive formal language, derived from the lambda-calculus, to provide a semantics that maps character strings into functions that manipulate symbols on strings. The interaction between two functions, or algorithms, is defined naturally within the language through function composition, and results in the production of a new function. An iterated map acting on sets of functions and a corresponding graph representation are defined. Their properties are useful to discuss the behavior of a fixed size ensemble of randomly interacting functions. This function gas'', or Turning gas'', is studied under various conditions, and evolves cooperative interaction patterns of considerable intricacy. These patterns adapt under the influence of perturbations consisting in the addition of new random functions to the system. Different organizations emerge depending on the availability of self-replicators.

  8. densityCut: an efficient and versatile topological approach for automatic clustering of biological data

    PubMed Central

    Ding, Jiarui; Shah, Sohrab; Condon, Anne

    2016-01-01

    Motivation: Many biological data processing problems can be formalized as clustering problems to partition data points into sensible and biologically interpretable groups. Results: This article introduces densityCut, a novel density-based clustering algorithm, which is both time- and space-efficient and proceeds as follows: densityCut first roughly estimates the densities of data points from a K-nearest neighbour graph and then refines the densities via a random walk. A cluster consists of points falling into the basin of attraction of an estimated mode of the underlining density function. A post-processing step merges clusters and generates a hierarchical cluster tree. The number of clusters is selected from the most stable clustering in the hierarchical cluster tree. Experimental results on ten synthetic benchmark datasets and two microarray gene expression datasets demonstrate that densityCut performs better than state-of-the-art algorithms for clustering biological datasets. For applications, we focus on the recent cancer mutation clustering and single cell data analyses, namely to cluster variant allele frequencies of somatic mutations to reveal clonal architectures of individual tumours, to cluster single-cell gene expression data to uncover cell population compositions, and to cluster single-cell mass cytometry data to detect communities of cells of the same functional states or types. densityCut performs better than competing algorithms and is scalable to large datasets. Availability and Implementation: Data and the densityCut R package is available from https://bitbucket.org/jerry00/densitycut_dev. Contact: condon@cs.ubc.ca or sshah@bccrc.ca or jiaruid@cs.ubc.ca Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153661

  9. Femtosecond spatial pulse shaping at the focal plane.

    PubMed

    Martínez-Matos, Ó; Vaveliuk, P; Izquierdo, J G; Loriot, V

    2013-10-21

    Spatial shaping of ultrashort laser beams at the focal plane is theoretically analyzed. The description of the pulse is performed by its expansion in terms of Laguerre-Gaussian orthonormal modes. This procedure gives both a comprehensive interpretation of the propagation dynamics and the required signal to encode onto a spatial light modulator for spatial shaping, without using iterative algorithms. As an example, pulses with top-hat and annular spatial profiles are designed and their dynamics analyzed. The interference of top-hat pulses is also investigated finding potential applications in high precision pump-probe experiments (without using delay lines) and for the creation of subwavelength ablation patterns. In addition, a novel class of ultrashort pulses possessing non-stationary orbital angular momentum is also proposed. These exotic pulses provide additional degrees of freedom that open up new perspectives in fields such as laser-matter interaction and micro-machining. PMID:24150344

  10. Plane parallel radiance transport for global illumination in vegetation

    SciTech Connect

    Max, N.; Mobley, C.; Keating, B.; Wu, E.H.

    1997-01-05

    This paper applies plane parallel radiance transport techniques to scattering from vegetation. The leaves, stems, and branches are represented as a volume density of scattering surfaces, depending only on height and the vertical component of the surface normal. Ordinary differential equations are written for the multiply scattered radiance as a function of the height above the ground, with the sky radiance and ground reflectance as boundary conditions. They are solved using a two-pass integration scheme to unify the two-point boundary conditions, and Fourier series for the dependence on the azimuthal angle. The resulting radiance distribution is used to precompute diffuse and specular `ambient` shading tables, as a function of height and surface normal, to be used in rendering, together with a z-buffer shadow algorithm for direct solar illumination.

  11. Source function and plane waves: Toward complete bader analysis.

    PubMed

    Tantardini, Christian; Ceresoli, Davide; Benassi, Enrico

    2016-09-01

    The source function (SF) is a topological descriptor that was introduced and developed by C. Gatti and R.W. Bader in 1998. The SF describes the contribution of each atom to the total electron density at a given point. To date, this descriptor has only been calculable from electron densities generated by all-electron (AE) methods for the investigation of single molecules or periodic systems. This study broadens the accessibility of the SF, offering its calculation from electron densities generated by plane wave (PW) methods. The new algorithm has been implemented in the open source code, CRITIC2. Our novel approach has been validated on a series of test systems, comparing the results obtained at PW level with those previously obtained through AE methods. © 2016 Wiley Periodicals, Inc. PMID:27364862

  12. Segmentation of the thalamus in multi-spectral MR images using a combination of atlas-based and gradient graph cut methods

    NASA Astrophysics Data System (ADS)

    Datteri, Ryan; Barillot, Christian; Dawant, Benoit M.; Lecoeur, Jeremy

    2010-03-01

    Two popular segmentation methods used today are atlas based and graph cut based segmentation techniques. The atlas based method deforms a manually segmented image onto a target image, resulting in an automatic segmentation. The graph cut segmentation method utilizes the graph cut paradigm by treating image segmentation as a max-flow problem. A specialized form of this algorithm was developed by Lecoeur et al [1], called the spectral graph cut algorithm. The goal of this paper is to combine both of these methods, creating a more stable atlas based segmentation algorithm that is less sensitive to the initial manual segmentation. The registration algorithm is used to automate and initialize the spectral graph cut algorithm as well as add needed spatial information, while the spectral graph cut algorithm is used to increase the robustness of the atlas method. To calculate the sensitivity of the algorithms, the initial manual segmentation of the atlas was both dilated and eroded 2 mm and the segmentation results were calculated. Results show that the atlas based segmentation segments the thalamus well with an average Dice Similarity Coefficient (DSC) of 0.87. The spectral graph cut method shows similar results with an average DSC measure of 0.88, with no statistical difference between the two methods. The atlas based method's DSC value, however, was reduced to 0.76 and 0.67 when dilated and eroded respectively, while the combined method retained a DSC value of 0.81 and 0.74, with a statistical difference found between the two methods.

  13. SU-E-J-245: Sensitivity of FDG PET Feature Analysis in Multi-Plane Vs. Single-Plane Extraction

    SciTech Connect

    Harmon, S; Jeraj, R; Galavis, P

    2015-06-15

    Purpose: Sensitivity of PET-derived texture features to reconstruction methods has been reported for features extracted from axial planes; however, studies often utilize three dimensional techniques. This work aims to quantify the impact of multi-plane (3D) vs. single-plane (2D) feature extraction on radiomics-based analysis, including sensitivity to reconstruction parameters and potential loss of spatial information. Methods: Twenty-three patients with solid tumors underwent [{sup 18}F]FDG PET/CT scans under identical protocols. PET data were reconstructed using five sets of reconstruction parameters. Tumors were segmented using an automatic, in-house algorithm robust to reconstruction variations. 50 texture features were extracted using two Methods: 2D patches along axial planes and 3D patches. For each method, sensitivity of features to reconstruction parameters was calculated as percent difference relative to the average value across reconstructions. Correlations between feature values were compared when using 2D and 3D extraction. Results: 21/50 features showed significantly different sensitivity to reconstruction parameters when extracted in 2D vs 3D (wilcoxon α<0.05), assessed by overall range of variation, Rangevar(%). Eleven showed greater sensitivity to reconstruction in 2D extraction, primarily first-order and co-occurrence features (average Rangevar increase 83%). The remaining ten showed higher variation in 3D extraction (average Range{sub var}increase 27%), mainly co-occurence and greylevel run-length features. Correlation of feature value extracted in 2D and feature value extracted in 3D was poor (R<0.5) in 12/50 features, including eight co-occurrence features. Feature-to-feature correlations in 2D were marginally higher than 3D, ∣R∣>0.8 in 16% and 13% of all feature combinations, respectively. Larger sensitivity to reconstruction parameters were seen for inter-feature correlation in 2D(σ=6%) than 3D (σ<1%) extraction. Conclusion: Sensitivity

  14. Implementation strategy of wafer-plane and aerial-plane inspection for advanced mask manufacture

    NASA Astrophysics Data System (ADS)

    Kim, Won-Sun; Chung, Dong-Hoon; Jeon, Chan-Uk; Cho, HanKu; Huang, William; Miller, John; Inderhees, Gregg; Pinto, Becky; Hur, Jiuk; Park, Kihun; Han, Jay

    2009-04-01

    Inspection of aggressive Optical Proximity Correction (OPC) designs, improvement of usable sensitivity, and reduction of cost of ownership are the three major challenges for today's mask inspection methodologies. In this paper we will discuss using aerial-plane inspection and wafer-plane inspection as novel approaches to address these challenges for advanced reticles. Wafer-plane inspection (WPI) and aerial-plane inspection (API) are two lithographic inspection modes. This suite of new inspection modes is based on high resolution reflected and transmitted light images in the reticle plane. These images together with scanner parameters are used to generate the aerial plane image using either vector or scalar models. Then information about the resist is applied to complete construction of the wafer plane image. API reports defects based on intensity differences between test and reference images at the aerial plane, whereas WPI applies a resist model to the aerial image to enhance discrimination between printable and non-printable defects at the wafer plane. The combination of WPI and API along with the industry standard Reticle Plane Inspection (RPI) is designed to handle complex OPC features, improve usable sensitivity and reduce the cost of ownership. This paper will explore the application of aerial-plane and wafer-plane die-to-die inspections on advanced reticles. Inspection sensitivity, inspectability, and comparison with Aerial Imaging Measurement System (AIMSTM[1]) or wafer-print-line will be analyzed. Most importantly, the implementation strategy of a combination of WPI and API along with RPI leading-edge mask manufacturing will be discussed.

  15. Double plane wave reverse time migration with plane wave Green's function

    NASA Astrophysics Data System (ADS)

    Zhao, Z.; Sen, M. K.; Stoffa, P. L.

    2015-12-01

    Reverse time migration (RTM) is effective in obtaining complex subsurface structures from seismic data. By solving the two-way wave equation, RTM can use entire wavefield for imaging. Although powerful computer are becoming available, the conventional pre-stack shot gather RTM is still computationally expensive. Solving forward and backward wavefield propagation for each source location and shot gather is extremely time consuming, especially for large seismic datasets. We present an efficient, accurate and flexible plane wave RTM in the frequency domain where we utilize a compressed plane wave dataset, known as the double plane wave (DPW) dataset. Provided with densely sampled seismic dataset, shot gathers can be decomposed into source and receiver plane wave components with minimal artifacts. The DPW RTM is derived under the Born approximation and utilizes frequency domain plane wave Green's function for imaging. Time dips in the shot profiles can help to estimate the range of plane wave components present in shot gathers. Therefore, a limited number of plane wave Green's functions are needed for imaging. Plane wave Green's functions can be used for imaging both source and receiver plane waves. Source and receiver reciprocity can be used for imaging plane wave components at no cost and save half of the computation time. As a result, the computational burden for migration is substantially reduced. Plane wave components can be migrated independently to recover specific targets with given dips, and ray parameter common image gathers (CIGs) can be generated after migration directly. The ray parameter CIGs can be used to justify the correctness of velocity models. Subsurface anisotropy effects can also be included in our imaging condition, provided with plane wave Green's functions in the anisotropic media.

  16. Fabrication of low cost cutting wheel via thermal spray process

    NASA Astrophysics Data System (ADS)

    Anasyida, A. S.; Nurulakmal, M. S.

    2012-09-01

    The present study is mainly focused on development of metal cutting wheel. The process involved hard particles (abrasives) being bonded on the wheel to enhance the cutting capability by thermal spraying process and followed by polymer bonding. The purpose of this work is to produce low cost cutting wheel and study the performance of cutting behavior. Two different types of powders; silicon carbide (SiC) as bonding agent and chromium carbide (Cr3C2) as abrasives were used. Wear loss and depth of cut as function of load, cutting time and cutting speed were evaluated. The results showed that the speed and load were the main factors that affected the cutting efficiency and the optimum cutting process can be performed at low cutting speed and high load or at high cutting speed and low load.

  17. Discrete element thermomechanical modelling of rock cutting with valuation of tool wear

    NASA Astrophysics Data System (ADS)

    Rojek, Jerzy

    2014-05-01

    The paper presents a thermomechanical discrete element model of rock cutting process. The thermomechanical formulation of the discrete element method considers mechanical and thermal phenomena and their reciprocal influence. The thermal model developed for transient heat conduction problems takes into account conductive heat transfer at the contact between particles and convection on the free surface. The thermal and mechanical problems are coupled by consideration of: (1) heat generated due to friction which is calculated in the mechanical problem and passed to the thermal solution, (2) influence of thermal expansion on mechanical interaction between particles. Estimation of temperature dependent wear has been included into the contact model. The coupled problem is solved using the staggered scheme.The thermomechanical algorithm has been implemented in a discrete element program and applied to simulation of rock cutting with single pick of a dredge cutter head. Numerical results confirm good performance of the developed algorithm.

  18. Extracting roads from remote sensing images with the aid of path morphology and parallelized graph cuts

    NASA Astrophysics Data System (ADS)

    Zhang, Zhulin; Zhou, Shaoguang

    2013-10-01

    While Graph Cuts are used for image segmentation, there exist two problems: how to get better initial information of foreground and background and how to improve the executing efficiency of Graph Cuts algorithm. To solve the first problem, path morphology and line segment matching algorithm are performed to get initial background information at the same time as getting initial foreground information, so non-road pixels similar with road pixels in gray value or texture are avoided being segmented as road points. To cope with the second problem, push-relabel strategy is chosen and its parallelized version based on NVIDIA CUDA platform is performed in this paper. Our strategy is performed on dense built-up area and suburban district and proved to be effective in both accuracy and efficiency.

  19. Traffic routing for multicomputer networks with virtual cut-through capability

    NASA Technical Reports Server (NTRS)

    Kandlur, Dilip D.; Shin, Kang G.

    1992-01-01

    Consideration is given to the problem of selecting routes for interprocess communication in a network with virtual cut-through capability, while balancing the network load and minimizing the number of times that a message gets buffered. An approach is proposed that formulates the route selection problem as a minimization problem with a link cost function that depends upon the traffic through the link. The form of this cost function is derived using the probability of establishing a virtual cut-through route. The route selection problem is shown to be NP-hard, and an algorithm is developed to incrementally reduce the cost by rerouting the traffic. The performance of this algorithm is exemplified by two network topologies: the hypercube and the C-wrapped hexagonal mesh.

  20. Adaptive image contrast enhancement algorithm for point-based rendering

    NASA Astrophysics Data System (ADS)

    Xu, Shaoping; Liu, Xiaoping P.

    2015-03-01

    Surgical simulation is a major application in computer graphics and virtual reality, and most of the existing work indicates that interactive real-time cutting simulation of soft tissue is a fundamental but challenging research problem in virtual surgery simulation systems. More specifically, it is difficult to achieve a fast enough graphic update rate (at least 30 Hz) on commodity PC hardware by utilizing traditional triangle-based rendering algorithms. In recent years, point-based rendering (PBR) has been shown to offer the potential to outperform the traditional triangle-based rendering in speed when it is applied to highly complex soft tissue cutting models. Nevertheless, the PBR algorithms are still limited in visual quality due to inherent contrast distortion. We propose an adaptive image contrast enhancement algorithm as a postprocessing module for PBR, providing high visual rendering quality as well as acceptable rendering efficiency. Our approach is based on a perceptible image quality technique with automatic parameter selection, resulting in a visual quality comparable to existing conventional PBR algorithms. Experimental results show that our adaptive image contrast enhancement algorithm produces encouraging results both visually and numerically compared to representative algorithms, and experiments conducted on the latest hardware demonstrate that the proposed PBR framework with the postprocessing module is superior to the conventional PBR algorithm and that the proposed contrast enhancement algorithm can be utilized in (or compatible with) various variants of the conventional PBR algorithm.

  1. Kalman Filter for Calibrating a Telescope Focal Plane

    NASA Technical Reports Server (NTRS)

    Kang, Bryan; Bayard, David

    2006-01-01

    The instrument-pointing frame (IPF) Kalman filter, and an algorithm that implements this filter, have been devised for calibrating the focal plane of a telescope. As used here, calibration signifies, more specifically, a combination of measurements and calculations directed toward ensuring accuracy in aiming the telescope and determining the locations of objects imaged in various arrays of photodetectors in instruments located on the focal plane. The IPF Kalman filter was originally intended for application to a spaceborne infrared astronomical telescope, but can also be applied to other spaceborne and ground-based telescopes. In the traditional approach to calibration of a telescope, (1) one team of experts concentrates on estimating parameters (e.g., pointing alignments and gyroscope drifts) that are classified as being of primarily an engineering nature, (2) another team of experts concentrates on estimating calibration parameters (e.g., plate scales and optical distortions) that are classified as being primarily of a scientific nature, and (3) the two teams repeatedly exchange data in an iterative process in which each team refines its estimates with the help of the data provided by the other team. This iterative process is inefficient and uneconomical because it is time-consuming and entails the maintenance of two survey teams and the development of computer programs specific to the requirements of each team. Moreover, theoretical analysis reveals that the engineering/ science iterative approach is not optimal in that it does not yield the best estimates of focal-plane parameters and, depending on the application, may not even enable convergence toward a set of estimates.

  2. Focal-Plane Array Receiver Systems for Space Communications

    NASA Astrophysics Data System (ADS)

    Britcliffe, M.; Hoppe, D.; Vilnrotter, V.

    2007-08-01

    Typical ground antennas intended for use in space communications require large apertures operating at high frequencies. The challenge involved with these applications is achieving the required antenna performance in terms of antenna aperture efficiency and pointing accuracy. The utilization of a focal-plane array in place of a standard single-mode feed minimizes these problems. This article discusses the key elements required to implement a focal-plane array on a large high-frequency antenna. The example of the NASA Deep Space Network 70-m antennas operating at 32 GHz has been chosen to illustrate these advantages. The design of a suitable feed and low-noise cryogenically cooled amplifier and the required signal-processing techniques are described. It is shown that adaptive least mean-square algorithms can be applied to the output of the array elements, in order to obtain the optimum combining weights in real time, even in the presence of dynamic interference (nearby spacecraft in the array's field of view or planetary radiation). This adaptive optimization capability maximizes the combined output signal-to-noise ratio in real time, ensuring maximum data throughput in the communications link when operating in the presence of receiver noise and external interference generally present during planetary encounters.

  3. Plane wave based selfconsistent solution of the GW Dyson equation

    NASA Astrophysics Data System (ADS)

    Wang, Lin-Wang; Cao, Huawei

    We have developed a selfconsistent procedure to calculate the full Dyson equation based on plane wave basis set. The whole formalism is based on the Greens function matrix of the plane wave G-vector. There is no truncation of the conduction band when the dielectric function is calculated. The Dyson equation is the variational minimum solution of the total energy in terms of the Greens function. The calculation uses the ''space-time'' method, with special algorithm for imaginary time integration and Fourier transformation. We have tested isolated molecules and periodic systems. The effects of selfconsistency compared to the G0W0 results will be presented. We will also discuss some special techniques used in the k-point summation for the periodic system. Massive parallelization is used to carry out such calculations. This work is supported by the Director, SC/BES/MSED of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, through the Material Theory program at Lawrence Berkeley National Laboratory.

  4. Detection of fallen trees in ALS point clouds by learning the Normalized Cut similarity function from simulated samples

    NASA Astrophysics Data System (ADS)

    Polewski, P.; Yao, W.; Heurich, M.; Krzystek, P.; Stilla, U.

    2014-08-01

    Fallen trees participate in several important forest processes, which motivates the need for information about their spatial distribution in forest ecosystems. Several studies have shown that airborne LiDAR is a valuable tool for obtaining such information. In this paper, we propose an integrated method of detecting fallen trees from ALS point clouds based on merging small segments into entire fallen stems via the Normalized Cut algorithm. A new approach to specifying the segment similarity function for the clustering algorithm is introduced, where the attribute weights are learned from labeled data instead of being determined manually. We notice the relationship between Normalized Cut's similarity function and a class of regression models, which leads us to the idea of approximating the task of learning the similarity function with the simpler task of learning a classifier. Moreover, we set up a virtual fallen tree generation scheme to simulate complex forest scenarios with multiple overlapping fallen stems. The classifier trained on this simulated data yields a similarity function for Normalized Cut. Tests on two sample plots from the Bavarian Forest National Park with manually labeled reference data show that the trained function leads to high-quality segmentations. Our results indicate that the proposed data-driven approach can be a successful alternative to time consuming trial-and-error or grid search methods of finding good feature weights for graph cut algorithms. Also, the methodology can be generalized to other applications of graph cut clustering in remote sensing.

  5. Research on spatial-variant property of bistatic ISAR imaging plane of space target

    NASA Astrophysics Data System (ADS)

    Guo, Bao-Feng; Wang, Jun-Ling; Gao, Mei-Guo

    2015-04-01

    The imaging plane of inverse synthetic aperture radar (ISAR) is the projection plane of the target. When taking an image using the range-Doppler theory, the imaging plane may have a spatial-variant property, which causes the change of scatter’s projection position and results in migration through resolution cells. In this study, we focus on the spatial-variant property of the imaging plane of a three-axis-stabilized space target. The innovative contributions are as follows. 1) The target motion model in orbit is provided based on a two-body model. 2) The instantaneous imaging plane is determined by the method of vector analysis. 3) Three Euler angles are introduced to describe the spatial-variant property of the imaging plane, and the image quality is analyzed. The simulation results confirm the analysis of the spatial-variant property. The research in this study is significant for the selection of the imaging segment, and provides the evidence for the following data processing and compensation algorithm. Project supported by the National Natural Science Foundation of China (Grant No. 61401024), the Shanghai Aerospace Science and Technology Innovation Foundation, China (Grant No. SAST201240), and the Basic Research Foundation of Beijing Institute of Technology (Grant No. 20140542001).

  6. An attempt to estimate out-of-plane lung nodule elongation in tomosynthesis images

    NASA Astrophysics Data System (ADS)

    Chodorowski, Artur; Arvidsson, Jonathan; Söderman, Christina; Svalkvist, Angelica; Johnsson, Šse A.; Bâth, Magnus

    2015-03-01

    In chest tomosynthesis (TS) the most commonly used reconstruction methods are based on Filtered Back Projection (FBP) algorithms. Due to the limited angular range of x-ray projections, FBP reconstructed data is typically associated with a low spatial resolution in the out-of-plane dimension. Lung nodule measures that depend on depth information such as 3D shape and volume are therefore difficult to estimate. In this paper the relation between features from FBP reconstructed lung nodules and the true out-of-plane nodule elongation is investigated and a method for estimating the out-of-plane nodule elongation is proposed. In order to study these relations a number of steps that include simulation of spheroidal-shaped nodules, insertion into synthetic data volumes, construction of TS-projections and FBP-reconstruction were performed. In addition, the same procedure was used to simulate nodules and insert them into clinical chest TS projection data. The reconstructed nodule data was then investigated with respect to in-plane diameter, out-of-plane elongation, and attenuation coefficient. It was found that the voxel value in each nodule increased linearly with nodule elongation, for nodules with a constant attenuation coefficient. Similarly, the voxel value increased linearly with in-plane diameter. These observations indicate the possibility to predict the nodule elongation from the reconstructed voxel intensity values. Such a method would represent a quantitative approach to chest tomosynthesis that may be useful in future work on volume and growth rate estimation of lung nodules.

  7. INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR MACHINE SHOP, LOOKING SOUTH TOWARD PLANING MILL. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

  8. GLAMER - II. Multiple-plane gravitational lensing

    NASA Astrophysics Data System (ADS)

    Petkova, Margarita; Metcalf, R. Benton; Giocoli, Carlo

    2014-12-01

    We present an extension to multiple planes of the gravitational lensing code GLAMER. The method entails projecting the mass in the observed light-cone on to a discrete number of lens planes and inverse ray-shooting from the image to the source plane. The mass on each plane can be represented as haloes, simulation particles, a projected mass map extracted form a numerical simulation or any combination of these. The image finding is done in a source-oriented fashion, where only regions of interest are iteratively refined on an initially coarse image plane grid. The calculations are performed in parallel on shared memory machines. The code is able to handle different types of analytic haloes (NFW, NSIE, power law, etc.), haloes extracted from numerical simulations and clusters constructed from semi-analytic models (MOKA). Likewise, there are several different options for modelling the source(s) which can be distributed throughout the light-cone. The distribution of matter in the light-cone can be either taken from a pre-existing N-body numerical simulations, from halo catalogues, or are generated from an analytic mass function. We present several tests of the code and demonstrate some of its applications such as generating mock images of galaxy and galaxy cluster lenses.

  9. A Viewpoint on the Quantity "Plane Angle"

    NASA Astrophysics Data System (ADS)

    Eder, W. E.

    1982-01-01

    Properties of the quantity "plane angle" are explored under the hypothesis that it is a dimensional quantity. The exploration proceeds especially with respect to the physical concept, its mathematical treatment, vector concepts, measurement theory, units of related quantities, engineering pragmatism, and SI. An attempt is made to bring these different relations into a rational, logical and consistent framework, and thus to justify the hypothesis. Various types of vectorial quantities are recognized, and their properties described with an outline of the necessary algebraic manipulations. The concept of plane angle is amplified, and its interdependence with the circular arc is explored. The resulting units of plane angle form a class of similar scales of measurement. Consequences of the confirmed hypothesis are developed for mathematical expressions involving trigonometric functions, rotational volumes and areas, mathematical limits, differentiation and series expansion. Consequences for mechanical rotational quantities are developed, with proposals for revisions to a number of expressions for derived units within SI. A revised definition for the quantity "plane angle" is stated to take account of the developed insights. There is a clear need to reconsider the status of plane angle and some other quantities within the international framework of SI.

  10. Focal Plane Metrology for the LSST Camera

    SciTech Connect

    A Rasmussen, Andrew P.; Hale, Layton; Kim, Peter; Lee, Eric; Perl, Martin; Schindler, Rafe; Takacs, Peter; Thurston, Timothy; /SLAC

    2007-01-10

    Meeting the science goals for the Large Synoptic Survey Telescope (LSST) translates into a demanding set of imaging performance requirements for the optical system over a wide (3.5{sup o}) field of view. In turn, meeting those imaging requirements necessitates maintaining precise control of the focal plane surface (10 {micro}m P-V) over the entire field of view (640 mm diameter) at the operating temperature (T {approx} -100 C) and over the operational elevation angle range. We briefly describe the hierarchical design approach for the LSST Camera focal plane and the baseline design for assembling the flat focal plane at room temperature. Preliminary results of gravity load and thermal distortion calculations are provided, and early metrological verification of candidate materials under cold thermal conditions are presented. A detailed, generalized method for stitching together sparse metrology data originating from differential, non-contact metrological data acquisition spanning multiple (non-continuous) sensor surfaces making up the focal plane, is described and demonstrated. Finally, we describe some in situ alignment verification alternatives, some of which may be integrated into the camera's focal plane.

  11. A method for determining the local magnetic induction near the cut edge of the ferromagnetic strip

    NASA Astrophysics Data System (ADS)

    Gmyrek, Z.

    2016-05-01

    The paper deals with the problem of precise determination of the local magnetic induction. The author proposes a new way of doing the measurements using the classical needle probe method. The proceeding algorithm combined with the proposed approximation of the ΔU voltage drop, contributes to a significant increase in the accuracy of the determination of the magnetic induction distribution in the zone near the cut edge.

  12. Rationalizing IT Rationing: 10 Ways to Cut the IT Budget (and What Not to Cut)

    ERIC Educational Resources Information Center

    Miller, Fred

    2009-01-01

    Whether because of falling stock values affecting institutional endowments, cutbacks in state spending, or declines in private giving, higher education has reduced spending, and information technology (IT) organizations have participated in the budget cuts. This is the tale of one institution's quest to cut technology costs while maintaining a…

  13. Budget Cuts: Financial Aid Offices Face Budget Cuts and Increasing Workload. Quick Scan Survey Results

    ERIC Educational Resources Information Center

    National Association of Student Financial Aid Administrators (NJ1), 2010

    2010-01-01

    The majority of college financial aid offices have seen cuts to their operating budgets this year compared to the 2007-08 academic year when the recession began, according to the National Association of Student Financial Aid Administrator's latest QuickScan Survey. Sixty-two percent of financial aid offices reported operating budget cuts this year…

  14. Plasma Cutting and Carbon-Arc Cutting. Welding Module 8. Instructor's Guide.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Instructional Materials Lab.

    This guide is intended to assist vocational educators in teaching the two units of a module in operating plasma cutting and carbon-arc cutting equipment. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The materials included in the module have been…

  15. Effect of Cutting Velocity / Stem Size on the Efficiency of NRCRI Cassave Stem Cutting Machine

    NASA Astrophysics Data System (ADS)

    Ikejiofor, M. C.

    2012-11-01

    The developed NRCRI (National Root Crops Research Institute) cassava stem cutting machine was evaluated. The cassava stems from the variety TME 419 were used. The sizes of the stem used were 1.8, 2.0, 2.3 and 2.6cm. Also, different cutting velocities of 1.20, 1.23 and 1.32m/s were used. The stakes produced has length of 2.5cm. Analysis of variance in RCBD was used to evaluate the effect of the cutting velocity and the stem size on the efficiency of the cutting machine. The result of the analysis showed that the cutting velocity had very highly significant effect, while the stem size had no significant effect at 5% level on the efficiency of the cutting machine. The data obtained also showed that the highest and least cutting efficiencies of 99.42 and 94.71% were obtained with the machine cutting velocities of 1.2 and 1.32m/s respectively.

  16. Detection of moving objects in image plane for robot navigation using monocular vision

    NASA Astrophysics Data System (ADS)

    Wang, Yin-Tien; Sun, Chung-Hsun; Chiou, Ming-Jang

    2012-12-01

    This article presents an algorithm for moving object detection (MOD) in robot visual simultaneous localization and mapping (SLAM). This MOD algorithm is designed based on the defining epipolar constraint for the corresponding feature points on image plane. An essential matrix obtained using the state estimator is utilized to represent the epipolar constraint. Meanwhile, the method of speeded-up robust feature (SURF) is employed in the algorithm to provide a robust detection for image features as well as a better description of landmarks and of moving objects in visual SLAM system. Experiments are carried out on a hand-held monocular camera to verify the performances of the proposed algorithm. The results show that the integration of MOD and SURF is efficient for robot navigating in dynamic environments.

  17. Optimisation Of The Cutting Up Of A Strip Of Float Glass

    NASA Astrophysics Data System (ADS)

    De Clerck, G.; Renard, G.; Smets, J.; Stappaerts, P.; Glaverbel, S. A.

    1986-07-01

    A description is given of an installation which makes it Possible to manage the cutting into Plates of float glass emerging from the annealing tunnel of a production unit, taking account of the pre-established quality criteria and the requirements imposed by the order book. This unit comprises first of all a device for detecting volume defects, based on scanning of the strip by a laser beam, which makes it possible to obtain, in real time, an electronic image of a section of the strip, showing the position and dimensions of the various defects. Secondly, this image is used in a data processing device which allocates to it an optimisation algorithm which Provides an optimal cutting diagram taking account of all the quality characteristics and the reauirements of orders. All the onerations are carried out fairly quickly, so that the cutting un can be controlled by the computer which, by another route, also controls sending of the cut sheets to the various packing stations, each corresponding to a different customer. Finally, this same computer checks the actual packaging of the cut sheets of glass.

  18. Experimental dynamic modelling of peripheral milling with process damping, structural and cutting force nonlinearities

    NASA Astrophysics Data System (ADS)

    Moradi, Hamed; Vossoughi, Gholamreza; Movahhedy, Mohammad R.

    2013-09-01

    In this paper, an extended dynamic model of peripheral milling process including process damping, structural and cutting force nonlinearities is presented. Cutting forces are described through a third-order polynomial function of chip thickness while a cubic nonlinear function is considered for the structural stiffness. Under stable and regenerative chatter conditions and using Fourier series components, closed form expressions for the nonlinear cutting forces are derived. Parameters of the proposed model are identified through a set of experiments. For this purpose, modal experiments and measurement of cutting forces (at various feed rates) are performed to determine the modal parameters and the coefficients of nonlinear cutting force model. In addition, coefficients of the structural stiffness and process damping are identified through the analysis of experimental and simulated stability lobes diagrams. Simulated stability lobes diagram is constructed based on two approaches: a trial and error (TE) based algorithm and semi-discretization method (SDM). The presented experimental method for model identification can be implemented on any industrial milling process.

  19. Solid-state curved focal plane arrays

    NASA Technical Reports Server (NTRS)

    Nikzad, Shouleh (Inventor); Hoenk, Michael (Inventor); Jones, Todd (Inventor)

    2010-01-01

    The present invention relates to curved focal plane arrays. More specifically, the present invention relates to a system and method for making solid-state curved focal plane arrays from standard and high-purity devices that may be matched to a given optical system. There are two ways to make a curved focal plane arrays starting with the fully fabricated device. One way, is to thin the device and conform it to a curvature. A second way, is to back-illuminate a thick device without making a thinned membrane. The thick device is a special class of devices; for example devices fabricated with high purity silicon. One surface of the device (the non VLSI fabricated surface, also referred to as the back surface) can be polished to form a curved surface.

  20. Plane gravitational waves in real connection variables

    SciTech Connect

    Hinterleitner, Franz; Major, Seth

    2011-02-15

    We investigate using plane-fronted gravitational wave space-times as model systems to study loop quantization techniques and dispersion relations. In this classical analysis we start with planar symmetric space-times in the real connection formulation. We reduce via Dirac constraint analysis to a final form with one canonical pair and one constraint, equivalent to the metric and Einstein equations of plane-fronted-with-parallel-rays waves. Because of the symmetries and use of special coordinates, general covariance is broken. However, this allows us to simply express the constraints of the consistent system. A recursive construction of Dirac brackets results in nonlocal brackets, analogous to those of self-dual fields, for the triad variables. Not surprisingly, this classical analysis produces no evidence for dispersion, i.e. a variable propagation speed of gravitational plane-fronted-with-parallel-rays waves.