Quartz crystal resonator g sensitivity measurement methods and recent results.

PubMed

Driscoll, M M

1990-01-01

A technique for accurate measurements of quartz crystal resonator vibration sensitivity is described. The technique utilizes a crystal oscillator circuit in which a prescribed length of coaxial cable is used to connect the resonator to the oscillator sustaining stage. A method is provided for determination and removal of measurement errors normally introduced as a result of cable vibration. In addition to oscillator-type measurements, it is also possible to perform similar vibration sensitivity measurements using a synthesized signal generator with the resonator installed in a passive phase bridge. Test results are reported for 40 and 50 MHz, fifth overtone AT-cut, and third overtone SC-cut crystals. Acceleration sensitivity (gamma vector) values for the SC-cut resonators were typically four times smaller (5x10(-10) per g) than for the AT-cut units. However, smaller unit-to-unit gamma vector magnitude variation was exhibited by the AT-cut resonators. Oscillator sustaining stage vibration sensitivity was characterized by an equivalent open-loop phase modulation of 10(-6) rad/g.

Calculation of Water Entry Problem for Free-falling Bodies Using a Developed Cartesian Cut Cell Mesh

NASA Astrophysics Data System (ADS)

Wenhua, Wang; Yanying, Wang

2010-05-01

This paper describes the development of free surface capturing method on Cartesian cut cell mesh to water entry problem for free-falling bodies with body-fluid interaction. The incompressible Euler equations for a variable density fluid system are presented as governing equations and the free surface is treated as a contact discontinuity by using free surface capturing method. In order to be convenient for dealing with the problem with moving body boundary, the Cartesian cut cell technique is adopted for generating the boundary-fitted mesh around body edge by cutting solid regions out of a background Cartesian mesh. Based on this mesh system, governing equations are discretized by finite volume method, and at each cell edge inviscid flux is evaluated by means of Roe's approximate Riemann solver. Furthermore, for unsteady calculation in time domain, a time accurate solution is achieved by a dual time-stepping technique with artificial compressibility method. For the body-fluid interaction, the projection method of momentum equations and exact Riemann solution are applied in the calculation of fluid pressure on the solid boundary. Finally, the method is validated by test case of water entry for free-falling bodies.

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.

Method and system for assigning a confidence metric for automated determination of optic disc location

DOEpatents

Karnowski, Thomas P [Knoxville, TN; Tobin, Jr., Kenneth W.; Muthusamy Govindasamy, Vijaya Priya [Knoxville, TN; Chaum, Edward [Memphis, TN

2012-07-10

A method for assigning a confidence metric for automated determination of optic disc location that includes analyzing a retinal image and determining at least two sets of coordinates locating an optic disc in the retinal image. The sets of coordinates can be determined using first and second image analysis techniques that are different from one another. An accuracy parameter can be calculated and compared to a primary risk cut-off value. A high confidence level can be assigned to the retinal image if the accuracy parameter is less than the primary risk cut-off value and a low confidence level can be assigned to the retinal image if the accuracy parameter is greater than the primary risk cut-off value. The primary risk cut-off value being selected to represent an acceptable risk of misdiagnosis of a disease having retinal manifestations by the automated technique.

Extreme Learning Machine and Particle Swarm Optimization in optimizing CNC turning operation

NASA Astrophysics Data System (ADS)

Janahiraman, Tiagrajah V.; Ahmad, Nooraziah; Hani Nordin, Farah

2018-04-01

The CNC machine is controlled by manipulating cutting parameters that could directly influence the process performance. Many optimization methods has been applied to obtain the optimal cutting parameters for the desired performance function. Nonetheless, the industry still uses the traditional technique to obtain those values. Lack of knowledge on optimization techniques is the main reason for this issue to be prolonged. Therefore, the simple yet easy to implement, Optimal Cutting Parameters Selection System is introduced to help the manufacturer to easily understand and determine the best optimal parameters for their turning operation. This new system consists of two stages which are modelling and optimization. In modelling of input-output and in-process parameters, the hybrid of Extreme Learning Machine and Particle Swarm Optimization is applied. This modelling technique tend to converge faster than other artificial intelligent technique and give accurate result. For the optimization stage, again the Particle Swarm Optimization is used to get the optimal cutting parameters based on the performance function preferred by the manufacturer. Overall, the system can reduce the gap between academic world and the industry by introducing a simple yet easy to implement optimization technique. This novel optimization technique can give accurate result besides being the fastest technique.

Additive lattice kirigami

PubMed Central

Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

2016-01-01

Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes. PMID:27679822

Additive lattice kirigami.

PubMed

Castle, Toen; Sussman, Daniel M; Tanis, Michael; Kamien, Randall D

2016-09-01

Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.

The Constant Intensity Cut Method applied to the KASCADE-Grande muon data

NASA Astrophysics Data System (ADS)

Arteaga-Velázquez, J. C.; Apel, W. D.; Badea, F.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Kolotaev, Y.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G.; Ulrich, H.; Walkowiak, W.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.

2009-12-01

The constant intensity cut method is a very useful tool to reconstruct the cosmic ray energy spectrum in order to combine or compare extensive air shower data measured for different attenuation depths independently of the MC model. In this contribution the method is used to explore the muon data of the KASCADE-Grande experiment. In particular, with this technique, the measured muon number spectra for different zenith angle ranges are compared and summed up to obtain a single muon spectrum for the measured showers. Preliminary results are presented, along with estimations of the systematic uncertainties associated with the analysis technique.

Uneven-aged management of old-growth spruce-fir forests: Cutting methods and stand structure goals for the initial entry

Treesearch

Robert R. Alexander; Carleton B. Edminster

1977-01-01

Topics discussed include: (1) cutting methods, (2) stand structure goals, which involve choosing a residual stocking level, selecting a maximum tree size, and establishing a diameter distribution using the "q" technique, and (3) harvesting and removal of trees. Examples illustrate how to determine realistic stand structures for the initial entry for...

Micro-structural characterization of precipitation-synthesized fluorapatite nano-material by transmission electron microscopy using different sample preparation techniques.

PubMed

Chinthaka Silva, G W; Ma, Longzhou; Hemmers, Oliver; Lindle, Dennis

2008-01-01

Fluorapatite is a naturally occurring mineral of the apatite group and it is well known for its high physical and chemical stability. There is a recent interest in this ceramic to be used as a radioactive waste form material due to its intriguing chemical and physical properties. In this study, the nano-sized fluorapatite particles were synthesized using a precipitation method and the material was characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Two well-known methods, called solution-drop and the microtome cutting, were used to prepare the sample for TEM analysis. It was found that the microtome cutting technique is advantageous for examining the particle shape and cross-sectional morphology as well as for obtaining ultra-thin samples. However, this method introduces artifacts and strong background contrast for high-resolution transmission electron microscopy (HRTEM) observation. On the other hand, phase image simulations showed that the solution-drop method is reliable and stable for HRTEM analysis. Therefore, in order to comprehensively analyze the microstructure and morphology of the nano-material, it is necessary to combine both solution-drop and microtome cutting techniques for TEM sample preparation.

Variability in the skin exposure of machine operators exposed to cutting fluids.

PubMed

Wassenius, O; Järvholm, B; Engström, T; Lillienberg, L; Meding, B

1998-04-01

This study describes a new technique for measuring skin exposure to cutting fluids and evaluates the variability of skin exposure among machine operators performing cyclic (repetitive) work. The technique is based on video recording and subsequent analysis of the video tape by means of computer-synchronized video equipment. The time intervals at which the machine operator's hand was exposed to fluid were registered, and the total wet time of the skin was calculated by assuming different evaporation times for the fluid. The exposure of 12 operators with different work methods was analyzed in 6 different workshops, which included a range of machine types, from highly automated metal cutting machines (ie, actual cutting and chip removal machines) requiring operator supervision to conventional metal cutting machines, where the operator was required to maneuver the machine and manually exchange products. The relative wet time varied between 0% and 100%. A significant association between short cycle time and high relative wet time was noted. However, there was no relationship between the degree of automatization of the metal cutting machines and wet time. The study shows that skin exposure to cutting fluids can vary considerably between machine operators involved in manufacturing processes using different types of metal cutting machines. The machine type was not associated with dermal wetness. The technique appears to give objective information about dermal wetness.

Pattern detection in forensic case data using graph theory: application to heroin cutting agents.

PubMed

Terrettaz-Zufferey, Anne-Laure; Ratle, Frédéric; Ribaux, Olivier; Esseiva, Pierre; Kanevski, Mikhail

2007-04-11

Pattern recognition techniques can be very useful in forensic sciences to point out to relevant sets of events and potentially encourage an intelligence-led style of policing. In this study, these techniques have been applied to categorical data corresponding to cutting agents found in heroin seizures. An application of graph theoretic methods has been performed, in order to highlight the possible relationships between the location of seizures and co-occurrences of particular heroin cutting agents. An analysis of the co-occurrences to establish several main combinations has been done. Results illustrate the practical potential of mathematical models in forensic data analysis.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dechristé, G., E-mail: Guillaume.Dechriste@math.u-bordeaux1.fr; CNRS, IMB, UMR 5251, F-33400 Talence; Mieussens, L., E-mail: Luc.Mieussens@math.u-bordeaux1.fr

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 amore » 3D unsteady simulation of the Crookes radiometer.« less

Imaging, cutting, and collecting instrument and method

DOEpatents

Tench, R.J.; Siekhaus, W.J.; Balooch, M.; Balhorn, R.L.; Allen, M.J.

1995-10-31

Instrumentation and techniques are described to image small objects, such as but not limited to individual human chromosomes, with nanometer resolution. This instrument and method are also used to cut-off identified parts of objects, to move around and manipulate the 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. The plural cantilevers are used with either sharp-tips or knife-edges. In addition, the invention can be utilized for measuring the hardness of materials. 10 figs.

Analysis of cutting force signals by wavelet packet transform for surface roughness monitoring in CNC turning

NASA Astrophysics Data System (ADS)

García Plaza, E.; Núñez López, P. J.

2018-01-01

On-line monitoring of surface finish in machining processes has proven to be a substantial advancement over traditional post-process quality control techniques by reducing inspection times and costs and by avoiding the manufacture of defective products. This study applied techniques for processing cutting force signals based on the wavelet packet transform (WPT) method for the monitoring of surface finish in computer numerical control (CNC) turning operations. The behaviour of 40 mother wavelets was analysed using three techniques: global packet analysis (G-WPT), and the application of two packet reduction criteria: maximum energy (E-WPT) and maximum entropy (SE-WPT). The optimum signal decomposition level (Lj) was determined to eliminate noise and to obtain information correlated to surface finish. The results obtained with the G-WPT method provided an in-depth analysis of cutting force signals, and frequency ranges and signal characteristics were correlated to surface finish with excellent results in the accuracy and reliability of the predictive models. The radial and tangential cutting force components at low frequency provided most of the information for the monitoring of surface finish. The E-WPT and SE-WPT packet reduction criteria substantially reduced signal processing time, but at the expense of discarding packets with relevant information, which impoverished the results. The G-WPT method was observed to be an ideal procedure for processing cutting force signals applied to the real-time monitoring of surface finish, and was estimated to be highly accurate and reliable at a low analytical-computational cost.

A new method to measure circular runout of end-milling spindle based on cutting mark

NASA Astrophysics Data System (ADS)

Zhou, Jianlai; Liu, Shuchun

2008-12-01

A practical method is introduced to measure the circular runout of a end-milling spindle system at high speed rotations without the need of a reference sphere. A workpiece is held on a linear slide which moves along the axial direction of the spindle. The spindle is then programmed to run at a specific speed. A very sharp edge cutter must be used and the depth of cut will be very shallow in order to keep the cutting force very small. The workpiece is then fed into the end mill in order to make a cutting mark of teens μm in depth. The cutting marks are circular, and their diameters are related to the circular runout of the spindle system. The cutting mark that is generated at a specific speed is expected to contain information about the spindle circular runout at this speed. In practice the cutting marks are not perfectly circular. Therefore, a best-fit circle of a cutting mark is needed to determine its diameter. A high-resolution edge detector machine is used for this purpose. Quantitative precision analysis was carried out to confirm the accuracy and repeatability of this new measurement technique. It is demonstrated that this technique for the measurement of spindle circular runout is an effective tool in verifying the actual running accuracy of spindles at their actual operating speeds and can be accomplished without the need for a reference sphere.

Development of low-cost silicon crystal growth techniques for terrestrial photovoltaic solar energy conversion

NASA Technical Reports Server (NTRS)

Zoutendyk, J. A.

1976-01-01

Because of the growing need for new sources of electrical energy, photovoltaic solar energy conversion is being developed. Photovoltaic devices are now being produced mainly from silicon wafers obtained from the slicing and polishing of cylindrically shaped single crystal ingots. Inherently high-cost processes now being used must either be eliminated or modified to provide low-cost crystalline silicon. Basic to this pursuit is the development of new or modified methods of crystal growth and, if necessary, crystal cutting. If silicon could be grown in a form requiring no cutting, a significant cost saving would potentially be realized. Therefore, several techniques for growth in the form of ribbons or sheets are being explored. In addition, novel techniques for low-cost ingot growth and cutting are under investigation.

Path Planning For A Class Of Cutting Operations

NASA Astrophysics Data System (ADS)

Tavora, Jose

1989-03-01

Optimizing processing time in some contour-cutting operations requires solving the so-called no-load path problem. This problem is formulated and an approximate resolution method (based on heuristic search techniques) is described. Results for real-life instances (clothing layouts in the apparel industry) are presented and evaluated.

Computer numeric control generation of toric surfaces

NASA Astrophysics Data System (ADS)

Bradley, Norman D.; Ball, Gary A.; Keller, John R.

1994-05-01

Until recently, the manufacture of toric ophthalmic lenses relied largely upon expensive, manual techniques for generation and polishing. Recent gains in computer numeric control (CNC) technology and tooling enable lens designers to employ single- point diamond, fly-cutting methods in the production of torics. Fly-cutting methods continue to improve, significantly expanding lens design possibilities while lowering production costs. Advantages of CNC fly cutting include precise control of surface geometry, rapid production with high throughput, and high-quality lens surface finishes requiring minimal polishing. As accessibility and affordability increase within the ophthalmic market, torics promise to dramatically expand lens design choices available to consumers.

An adaptive simplex cut-cell method for high-order discontinuous Galerkin discretizations of elliptic interface problems and conjugate heat transfer problems

NASA Astrophysics Data System (ADS)

Sun, Huafei; Darmofal, David L.

2014-12-01

In this paper we propose a new high-order solution framework for interface problems on non-interface-conforming meshes. The framework consists of a discontinuous Galerkin (DG) discretization, a simplex cut-cell technique, and an output-based adaptive scheme. We first present a DG discretization with a dual-consistent output evaluation for elliptic interface problems on interface-conforming meshes, and then extend the method to handle multi-physics interface problems, in particular conjugate heat transfer (CHT) problems. The method is then applied to non-interface-conforming meshes using a cut-cell technique, where the interface definition is completely separate from the mesh generation process. No assumption is made on the interface shape (other than Lipschitz continuity). We then equip our strategy with an output-based adaptive scheme for an accurate output prediction. Through numerical examples, we demonstrate high-order convergence for elliptic interface problems and CHT problems with both smooth and non-smooth interface shapes.

The effects of the Er:YAG laser on trabecular bone micro-architecture: Comparison with conventional dental drilling by micro-computed tomographic and histological techniques

PubMed Central

Zeitouni, Jihad; Clough, Bret; Zeitouni, Suzanne; Saleem, Mohammed; Al Aisami, Kenan; Gregory, Carl

2017-01-01

Background: The use of lasers has become increasingly common in the field of medicine and dentistry, and there is a growing need for a deeper understanding of the procedure and its effects on tissue. The aim of this study was to compare the erbium-doped yttrium aluminium garnet (Er:YAG) laser and conventional drilling techniques, by observing the effects on trabecular bone microarchitecture and the extent of thermal and mechanical damage. Methods: Ovine femoral heads were employed to mimic maxillofacial trabecular bone, and cylindrical osteotomies were generated to mimic implant bed preparation. Various laser parameters were tested, as well as a conventional dental drilling technique. The specimens were then subjected to micro-computed tomographic (μCT) histomorphometic analysis and histology. Results: Herein, we demonstrate that mCT measurements of trabecular porosity provide quantitative evidence that laser-mediated cutting preserves the trabecular architecture and reduces thermal and mechanical damage at the margins of the cut. We confirmed these observations with histological studies. In contrast with laser-mediated cutting, conventional drilling resulted in trabecular collapse, reduction of porosity at the margin of the cut and histological signs of thermal damage. Conclusions: This study has demonstrated, for the first time, that mCT and quantification of porosity at the margin of the cut provides a quantitative insight into damage caused by bone cutting techniques. We further show that with laser-mediated cutting, the marrow remains exposed to the margins of the cut, facilitating cellular infiltration and likely accelerating healing. However, with drilling, trabecular collapse and thermal damage is likely to delay healing by restricting the passage of cells to the site of injury and causing localized cell death. PMID:29416849

Preparation of pre-cut corneas from fresh donated whole globes for Descemet's stripping automated keratoplasty: 3-year results at the Central Eye Bank of Iran.

PubMed

Kanavi, Mozhgan Rezaei; Javadi, Mohammad Ali; Javadi, Fatemeh; Chamani, Tahereh

2014-09-01

To describe the technique and the results of the preparation of pre-cut corneas for Descemet's stripping automated endothelial keratoplasty (DSAEK) during a 3-year period at the Central Eye Bank of Iran (CEBI). The method of preparation of pre-cut corneas from donated whole globes at the CEBI is described and the frequency and percentage of pre-cut corneas prepared for DSAEK, between April 2009 and March 2012, are specified. Moreover, post-operative reports are reviewed for any complaints about using pre-cut tissues for DSAEK. Out of the 1,518 donated whole globes appropriate for DSAEK, 1,478 (97.4 %) pre-cut corneas were successfully prepared. The method of preparation failed in 40 (2.6 %) cases. Based on the eye bank post-operative reports, thickness of pre-cut tissues for DSAEK was deemed unacceptable in only 6 (0.4 %) cases prior to surgery; five of these were too thick and one was too thin. Preparation of pre-cut corneas, for DSAEK from donated whole globes, in the CEBI is a safe and easy method, with very good preservation of endothelial cells after the preparation of the pre-cut corneas and reduced risks from corneal manipulation.

Improved transformer-winding method

NASA Technical Reports Server (NTRS)

Mclyman, W. T.

1978-01-01

Proposed technique using special bobbin and fixture to wind copper wire directly on core eliminates need core cut prior to assembly. Application of technique could result in production of quieter core with increased permeability and no localized heating.

Improving semi-automated segmentation by integrating learning with active sampling

NASA Astrophysics Data System (ADS)

Huo, Jing; Okada, Kazunori; Brown, Matthew

2012-02-01

Interactive segmentation algorithms such as GrowCut usually require quite a few user interactions to perform well, and have poor repeatability. In this study, we developed a novel technique to boost the performance of the interactive segmentation method GrowCut involving: 1) a novel "focused sampling" approach for supervised learning, as opposed to conventional random sampling; 2) boosting GrowCut using the machine learned results. We applied the proposed technique to the glioblastoma multiforme (GBM) brain tumor segmentation, and evaluated on a dataset of ten cases from a multiple center pharmaceutical drug trial. The results showed that the proposed system has the potential to reduce user interaction while maintaining similar segmentation accuracy.

Religious slaughter: evaluation of current practices in selected countries.

PubMed

Velarde, A; Rodriguez, P; Dalmau, A; Fuentes, C; Llonch, P; von Holleben, K V; Anil, M H; Lambooij, J B; Pleiter, H; Yesildere, T; Cenci-Goga, B T

2014-01-01

As part of the project "Religious slaughter (DIALREL): improving knowledge and expertise through dialogue and debate on issues of welfare, legislation and socio-economic aspects", this paper discusses an evaluation of current practices during Halal and Shechita slaughter in cattle, sheep, goats and poultry. During religious slaughter, animals are killed with and without stunning by a transverse incision across the neck that is cutting the skin, muscles (brachiocephalic, sternocephalic, sternohyoid, and sternothyroid), trachea, esophagus, carotid arteries, jugular veins and the major, superficial and deep nerves of the cervical plexus. In this report, the restraint methods, stunning, neck cutting, exsanguination, slaughter techniques and postcut handling in the abattoir were assessed for religious slaughter. Information about the procedures used during religious slaughter in Belgium, Germany, Italy, the Netherlands, Spain, the UK, Turkey and Australia was collected by means of spot visits to abattoirs. To standardize the information gathered during the spot visits three guidelines were designed, one for each species, and translated into the national languages of the countries involved. The document included questions on the handling and restraint methods (stunning, neck cutting/exsanguination/slaughter techniques and postcut handling performed under religious practices) and for pain and distress of the animal during the restraint, neck cutting and induction to death in each abattoir. Results showed differences in the time from restraining to stun and to cut in the neck cutting procedures and in the time from cut to death. © 2013.

High precision laser processing of sensitive materials by Microjet

NASA Astrophysics Data System (ADS)

Sibailly, Ochelio D.; Wagner, Frank R.; Mayor, Laetitia; Richerzhagen, Bernold

2003-11-01

Material laser cutting is well known and widely used in industrial processes, including micro fabrication. An increasing number of applications require nevertheless a superior machining quality than can be achieved using this method. A possibility to increase the cut quality is to opt for the water-jet guided laser technology. In this technique the laser is conducted to the work piece by total internal reflection in a thin stable water-jet, comparable to the core of an optical fiber. The water jet guided laser technique was developed originally in order to reduce the heat damaged zone near the cut, but in fact many other advantages were observed due to the usage of a water-jet instead of an assist gas stream applied in conventional laser cutting. In brief, the advantages are three-fold: the absence of divergence due to light guiding, the efficient melt expulsion, and optimum work piece cooling. In this presentation we will give an overview on several industrial applications of the water-jet guided laser technique. These applications range from the cutting of CBN or ferrite cores to the dicing of thin wafers and the manufacturing of stencils, each illustrates the important impact of the water-jet usage.

Discrimination methods for biological contaminants in fresh-cut lettuce based on VNIR and NIR hyperspectral imaging

NASA Astrophysics Data System (ADS)

Mo, Changyeun; Kim, Giyoung; Kim, Moon S.; Lim, Jongguk; Lee, Seung Hyun; Lee, Hong-Seok; Cho, Byoung-Kwan

2017-09-01

The rapid detection of biological contaminants such as worms in fresh-cut vegetables is necessary to improve the efficiency of visual inspections carried out by workers. Multispectral imaging algorithms were developed using visible-near-infrared (VNIR) and near-infrared (NIR) hyperspectral imaging (HSI) techniques to detect worms in fresh-cut lettuce. The optimal wavebands that can detect worms in fresh-cut lettuce were investigated for each type of HSI using one-way ANOVA. Worm-detection imaging algorithms for VNIR and NIR imaging exhibited prediction accuracies of 97.00% (RI547/945) and 100.0% (RI1064/1176, SI1064-1176, RSI-I(1064-1173)/1064, and RSI-II(1064-1176)/(1064+1176)), respectively. The two HSI techniques revealed that spectral images with a pixel size of 1 × 1 mm or 2 × 2 mm had the best classification accuracy for worms. The results demonstrate that hyperspectral reflectance imaging techniques have the potential to detect worms in fresh-cut lettuce. Future research relating to this work will focus on a real-time sorting system for lettuce that can simultaneously detect various defects such as browning, worms, and slugs.

Comparison of surface roughness and chip characteristics obtained under different modes of lubrication during hard turning of AISI H13 tool work steel.

NASA Astrophysics Data System (ADS)

Raj, Anil; Wins, K. Leo Dev; Varadarajan, A. S.

2016-09-01

Surface roughness is one of the important parameters, which not only affects the service life of a component but also serves as a good index of machinability. Near Dry Machining, methods (NDM) are considered as sustainable alternative for workshops trying to bring down their dependence on cutting fluids and the hazards associated with their indiscriminate usage. The present work presents a comparison of the surface roughness and chip characteristics during hard turning of AISI H13 tool work steel using hard metal inserts under two popular NDM techniques namely the minimal fluid application and the Minimum Quantity Lubrication technique(MQL) using an experiment designed based on Taguchi's techniques. The statistical method of analysis of variance (ANOVA) was used to determine the relative significance of input parameters consisting of cutting speed, feed and depth of cut on the attainable surface finish and the chip characteristics. It was observed that the performance during minimal fluid application was better than that during MQL application.

Calculation of the ELISA's cut-off based on the change-point analysis method for detection of Trypanosoma cruzi infection in Bolivian dogs in the absence of controls.

PubMed

Lardeux, Frédéric; Torrico, Gino; Aliaga, Claudia

2016-07-04

In ELISAs, sera of individuals infected by Trypanosoma cruzi show absorbance values above a cut-off value. The cut-off is generally computed by means of formulas that need absorbance readings of negative (and sometimes positive) controls, which are included in the titer plates amongst the unknown samples. When no controls are available, other techniques should be employed such as change-point analysis. The method was applied to Bolivian dog sera processed by ELISA to diagnose T. cruzi infection. In each titer plate, the change-point analysis estimated a step point which correctly discriminated among known positive and known negative sera, unlike some of the six usual cut-off formulas tested. To analyse the ELISAs results, the change-point method was as good as the usual cut-off formula of the form "mean + 3 standard deviation of negative controls". Change-point analysis is therefore an efficient alternative method to analyse ELISA absorbance values when no controls are available.

Drill Cuttings-based Methodology to Optimize Multi-stage Hydraulic Fracturing in Horizontal Wells and Unconventional Gas Reservoirs

NASA Astrophysics Data System (ADS)

Ortega Mercado, Camilo Ernesto

Horizontal drilling and hydraulic fracturing techniques have become almost mandatory technologies for economic exploitation of unconventional gas reservoirs. Key to commercial success is minimizing the risk while drilling and hydraulic fracturing these wells. Data collection is expensive and as a result this is one of the first casualties during budget cuts. As a result complete data sets in horizontal wells are nearly always scarce. In order to minimize the data scarcity problem, the research addressed throughout this thesis concentrates on using drill cuttings, an inexpensive direct source of information, for developing: 1) A new methodology for multi-stage hydraulic fracturing optimization of horizontal wells without any significant increases in operational costs. 2) A new method for petrophysical evaluation in those wells with limited amount of log information. The methods are explained using drill cuttings from the Nikanassin Group collected in the Deep Basin of the Western Canada Sedimentary Basin (WCSB). Drill cuttings are the main source of information for the proposed methodology in Item 1, which involves the creation of three 'log tracks' containing the following parameters for improving design of hydraulic fracturing jobs: (a) Brittleness Index, (b) Measured Permeability and (c) An Indicator of Natural Fractures. The brittleness index is primarily a function of Poisson's ratio and Young Modulus, parameters that are obtained from drill cuttings and sonic logs formulations. Permeability is measured on drill cuttings in the laboratory. The indication of natural fractures is obtained from direct observations on drill cuttings under the microscope. Drill cuttings are also the main source of information for the new petrophysical evaluation method mentioned above in Item 2 when well logs are not available. This is important particularly in horizontal wells where the amount of log data is almost non-existent in the vast majority of the wells. By combining data from drill cuttings and previously available empirical relationships developed from cores it is possible to estimate water saturations, pore throat apertures, capillary pressures, flow units, porosity (or cementation) exponent m, true formation resistivity Rt, distance to a water table (if present), and to distinguish the contributions of viscous and diffusion-like flow in the tight gas formation. The method further allows the construction of Pickett plots using porosity and permeability obtained from drill cuttings, without previous availability of well logs. The method assumes the existence of intervals at irreducible water saturation, which is the case of the Nikanassin Group throughout the gas column. The new methods mentioned above are not meant to replace the use of detailed and sophisticated evaluation techniques. But the proposed methods provide a valuable and practical aid in those cases where geomechanical and petrophysical information are scarce.

Evaluation of laser cutting process with auxiliary gas pressure by soft computing approach

NASA Astrophysics Data System (ADS)

Lazov, Lyubomir; Nikolić, Vlastimir; Jovic, Srdjan; Milovančević, Miloš; Deneva, Heristina; Teirumenieka, Erika; Arsic, Nebojsa

2018-06-01

Evaluation of the optimal laser cutting parameters is very important for the high cut quality. This is highly nonlinear process with different parameters which is the main challenge in the optimization process. Data mining methodology is one of most versatile method which can be used laser cutting process optimization. Support vector regression (SVR) procedure is implemented since it is a versatile and robust technique for very nonlinear data regression. The goal in this study was to determine the optimal laser cutting parameters to ensure robust condition for minimization of average surface roughness. Three cutting parameters, the cutting speed, the laser power, and the assist gas pressure, were used in the investigation. As a laser type TruLaser 1030 technological system was used. Nitrogen as an assisted gas was used in the laser cutting process. As the data mining method, support vector regression procedure was used. Data mining prediction accuracy was very high according the coefficient (R2) of determination and root mean square error (RMSE): R2 = 0.9975 and RMSE = 0.0337. Therefore the data mining approach could be used effectively for determination of the optimal conditions of the laser cutting process.

An investigation of the use of discriminant analysis for the classification of blade edge type from cut marks made by metal and bamboo blades.

PubMed

Bonney, Heather

2014-08-01

Analysis of cut marks in bone is largely limited to two dimensional qualitative description. Development of morphological classification methods using measurements from cut mark cross sections could have multiple uses across palaeoanthropological and archaeological disciplines, where cutting edge types are used to investigate and reconstruct behavioral patterns. An experimental study was undertaken, using porcine bone, to determine the usefulness of discriminant function analysis in classifying cut marks by blade edge type, from a number of measurements taken from their cross-sectional profile. The discriminant analysis correctly classified 86.7% of the experimental cut marks into serrated, non-serrated and bamboo blade types. The technique was then used to investigate a series of cut marks of unknown origin from a collection of trophy skulls from the Torres Strait Islands, to investigate whether they were made by bamboo or metal blades. Nineteen out of twenty of the cut marks investigated were classified as bamboo which supports the non-contemporaneous ethnographic accounts of the knives used for trophy taking and defleshing remains. With further investigation across a variety of blade types, this technique could prove a valuable tool in the interpretation of cut mark evidence from a wide variety of contexts, particularly in forensic anthropology where the requirement for presentation of evidence in a statistical format is becoming increasingly important. © 2014 Wiley Periodicals, Inc.

Laser processing of phenolic wood substitutes

NASA Astrophysics Data System (ADS)

Quintero, F.; Riveiro, A.; Lusquiños, F.; Penide, J.; Arias-González, F.; del Val, J.; Comesaña, R.; Boutinguiza, M.; Pou, J.

2013-11-01

Phenolic resin boards (PRB) are wood substitutes that comprises of a thick core exclusively made of phenolic resin covered by a thin sheet of melamine resin imitating the aspect of natural wood. The use of these materials in furniture and in construction industry has proliferated during last years. Boards made of phenolic resins are dense, hard and very difficult to cut using band saws, disc saws, or milling cutters. Nevertheless, these difficulties can be overcome by means of laser cutting, which is one of the most firmly established techniques for separating materials. This is due to the great advantages of this technique over traditional cutting methods, such as its versatility and flexibility that allow effective cutting. Nevertheless, charring of the cut edge surface caused by laser induced thermal degradation degrades the cut quality under non-optimized processing conditions. In this research work the viability and quality of CO2 laser cutting process of phenolic resin boards and wood particleboard panels has been evaluated. The present work validates the cut of phenolic resin boards by CO2 lasers using a high laser power and elevated cutting speeds. Moreover, this process involves a serious health hazard since the combustion and decomposition of wood may produce fumes and vapors, which can be toxic and carcinogenic according to the International Chemical Safety Cards (ICSC). Therefore, this work was complemented by the assessment of the potential toxicity of the condensed residues formed on the cut edges, and assessment of the chemistry of the generated fumes by chromatography.

Shaping Cutter Original Profile for Fine-module Ratchet Teeth Cutting

NASA Astrophysics Data System (ADS)

Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.

2018-03-01

The methods for determining geometric characteristics of a theoretical original profile of the cutter for cutting ratchet teeth with a module of 0.3–1.0 mm are considered in the article. Design models describing the shaping process of cutting edges of cutter teeth are developed. Systems of expressions for determining coordinates of the points of front and back edges of cutter teeth; the workpiece angles of rotation during the cutting process; the minimum cutter radius are received. The basic data when using the proposed technique are: radii of circumferences passing through cavities of cutter teeth and external cut teeth; the gradient angle and length of straight section of the front edge of a cut tooth; angles of rotation of the cutter and the workpiece at the moment of shaping.

Satellite-based assessment of grassland yields

NASA Astrophysics Data System (ADS)

Grant, K.; Siegmund, R.; Wagner, M.; Hartmann, S.

2015-04-01

Cutting date and frequency are important parameters determining grassland yields in addition to the effects of weather, soil conditions, plant composition and fertilisation. Because accurate and area-wide data of grassland yields are currently not available, cutting frequency can be used to estimate yields. In this project, a method to detect cutting dates via surface changes in radar images is developed. The combination of this method with a grassland yield model will result in more reliable and regional-wide numbers of grassland yields. For the test-phase of the monitoring project, a study area situated southeast of Munich, Germany, was chosen due to its high density of managed grassland. For determining grassland cutting robust amplitude change detection techniques are used evaluating radar amplitude or backscatter statistics before and after the cutting event. CosmoSkyMed and Sentinel-1A data were analysed. All detected cuts were verified according to in-situ measurements recorded in a GIS database. Although the SAR systems had various acquisition geometries, the amount of detected grassland cut was quite similar. Of 154 tested grassland plots, covering in total 436 ha, 116 and 111 cuts were detected using CosmoSkyMed and Sentinel-1A radar data, respectively. Further improvement of radar data processes as well as additional analyses with higher sample number and wider land surface coverage will follow for optimisation of the method and for validation and generalisation of the results of this feasibility study. The automation of this method will than allow for an area-wide and cost efficient cutting date detection service improving grassland yield models.

Evaluating the effects of pinyon thinning treatments at a wildland urban interface

Treesearch

J. R. Matchett; Matthew Brooks; Anne Halford; Dale Johnson; Helen Smith

2010-01-01

This study evaluated the short-term effects of thinning methods for pinyon pine woodlands at two sites in the southwestern Great Basin. Both cut/pile/burn and mastication treatments were equally effective at reducing the target fuels which were mature, live pinyon trees. Application costs though differed substantially, with the cut/pile/burn technique being less...

The effect of technique change on knee loads during sidestep cutting.

PubMed

Dempsey, Alasdair R; Lloyd, David G; Elliott, Bruce C; Steele, Julie R; Munro, Bridget J; Russo, Kylie A

2007-10-01

To identify the effect of modifying sidestep cutting technique on knee loads and predict what impact such change would have on the risk of noncontact anterior cruciate ligament injury. A force platform and motion-analysis system were used to record ground-reaction forces and track the trajectories of markers on 15 healthy males performing sidestep cutting tasks using their normal technique and nine different imposed techniques. A kinematic and inverse dynamic model was used to calculate the three-dimensional knee postures and moments. The imposed techniques of foot wide and torso leaning in the opposite direction to the cut resulted in increased peak valgus moments experienced in weight acceptance. Higher peak internal rotation moments were found for the foot wide and torso rotation in the opposite direction to the cut techniques. The foot rotated in technique resulted in lower mean flexion/extension moments, whereas the foot wide condition resulted in higher mean flexion/extension moments. The flexed knee, torso rotated in the opposite direction to the cut and torso leaning in the same direction as the cut techniques had significantly more knee flexion at heel strike. Sidestep cutting technique had a significant effect on loads experienced at the knee. The techniques that produced higher valgus and internal rotation moments at the knee, such as foot wide, torso leaning in the opposite direction to the cut and torso rotating in the opposite direction to the cut, may place an athlete at higher risk of injury because these knee loads have been shown to increase the strain on the anterior cruciate ligament. Training athletes to avoid such body positions may result in a reduced risk of noncontact anterior cruciate ligament injures.

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.

MIRAP, microcomputer reliability analysis program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jehee, J.N.T.

1989-01-01

A program for a microcomputer is outlined that can determine minimal cut sets from a specified fault tree logic. The speed and memory limitations of the microcomputers on which the program is implemented (Atari ST and IBM) are addressed by reducing the fault tree's size and by storing the cut set data on disk. Extensive well proven fault tree restructuring techniques, such as the identification of sibling events and of independent gate events, reduces the fault tree's size but does not alter its logic. New methods are used for the Boolean reduction of the fault tree logic. Special criteria formore » combining events in the 'AND' and 'OR' logic avoid the creation of many subsuming cut sets which all would cancel out due to existing cut sets. Figures and tables illustrates these methods. 4 refs., 5 tabs.« less

A logic-based method for integer programming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hooker, J.; Natraj, N.R.

1994-12-31

We propose a logic-based approach to integer programming that replaces traditional branch-and-cut techniques with logical analogs. Integer variables are regarded as atomic propositions. The constraints give rise to logical formulas that are analogous to separating cuts. No continuous relaxation is used. Rather, the cuts are selected so that they can be easily solved as a discrete relaxation. (In fact, defining a relaxation and generating cuts are best seen as the same problem.) We experiment with relaxations that have a k-tree structure and can be solved by nonserial dynamic programming. We also present logic-based analogs of facet-defining cuts, Chv{acute a}tal rank,more » etc. We conclude with some preliminary computational results.« less

Laser assisted machining: a state of art review

NASA Astrophysics Data System (ADS)

Punugupati, Gurabvaiah; Kandi, Kishore Kumar; Bose, P. S. C.; Rao, C. S. P.

2016-09-01

Difficult-to-cut materials have increasing demand in aerospace and automobile industries due to their high yield stress, high strength to weight ratio, high toughness, high wear resistance, high creep, high corrosion resistivity, ability to retain high strength at high temperature, etc. The machinability of these advanced materials, using conventional methods of machining is typical due to the high temperature and pressure at the cutting zone and tool and properties such as low thermal conductivity, high cutting forces and cutting temperatures makes the materials difficult to machine. Laser assisted machining (LAM) is a new and innovative technique for machining the difficult-to-cut materials. This paper deals with a review on the advances in lasers, tools and the mechanism of machining using LAM and their effects.

A modified technique to reduce tibial keel cutting errors during an Oxford unicompartmental knee arthroplasty.

PubMed

Inui, Hiroshi; Taketomi, Shuji; Tahara, Keitarou; Yamagami, Ryota; Sanada, Takaki; Tanaka, Sakae

2017-03-01

Bone cutting errors can cause malalignment of unicompartmental knee arthroplasties (UKA). Although the extent of tibial malalignment due to horizontal cutting errors has been well reported, there is a lack of studies evaluating malalignment as a consequence of keel cutting errors, particularly in the Oxford UKA. The purpose of this study was to examine keel cutting errors during Oxford UKA placement using a navigation system and to clarify whether two different tibial keel cutting techniques would have different error rates. The alignment of the tibial cut surface after a horizontal osteotomy and the surface of the tibial trial component was measured with a navigation system. Cutting error was defined as the angular difference between these measurements. The following two techniques were used: the standard "pushing" technique in 83 patients (group P) and a modified "dolphin" technique in 41 patients (group D). In all 123 patients studied, the mean absolute keel cutting error was 1.7° and 1.4° in the coronal and sagittal planes, respectively. In group P, there were 22 outlier patients (27 %) in the coronal plane and 13 (16 %) in the sagittal plane. Group D had three outlier patients (8 %) in the coronal plane and none (0 %) in the sagittal plane. Significant differences were observed in the outlier ratio of these techniques in both the sagittal (P = 0.014) and coronal (P = 0.008) planes. Our study demonstrated overall keel cutting errors of 1.7° in the coronal plane and 1.4° in the sagittal plane. The "dolphin" technique was found to significantly reduce keel cutting errors on the tibial side. This technique will be useful for accurate component positioning and therefore improve the longevity of Oxford UKAs. Retrospective comparative study, Level III.

Optimisation Of Cutting Parameters Of Composite Material Laser Cutting Process By Taguchi Method

NASA Astrophysics Data System (ADS)

Lokesh, S.; Niresh, J.; Neelakrishnan, S.; Rahul, S. P. Deepak

2018-03-01

The aim of this work is to develop a laser cutting process model that can predict the relationship between the process input parameters and resultant surface roughness, kerf width characteristics. The research conduct is based on the Design of Experiment (DOE) analysis. Response Surface Methodology (RSM) is used in this work. It is one of the most practical and most effective techniques to develop a process model. Even though RSM has been used for the optimization of the laser process, this research investigates laser cutting of materials like Composite wood (veneer)to be best circumstances of laser cutting using RSM process. The input parameters evaluated are focal length, power supply and cutting speed, the output responses being kerf width, surface roughness, temperature. To efficiently optimize and customize the kerf width and surface roughness characteristics, a machine laser cutting process model using Taguchi L9 orthogonal methodology was proposed.

Damage Detection in Concrete Elements with Surface Wave Measurements

DTIC Science & Technology

1992-01-01

Structures, identified the need for "Better techniques for detection of flaws or defects inside structural members". At the same conference, the...1 6 12 1 7 13 19 13 7 18 12 6 17 11 5 14 8 2 10 8 2 83 Saw cut Sawm cu Saw cut Sawcu SSaw cut Figre4. -I ltie ocaio o Dmae ndSoc- RcieAra 84 4.2...cracking and defects . Some methods used in the past to determine the size and location of cracks are the P-wave arrival time, imaging systems, time

Wire blade development for Fixed Abrasive Slicing Technique (FAST) slicing

NASA Technical Reports Server (NTRS)

Khattak, C. P.; Schmid, F.; Smith, M. B.

1982-01-01

A low cost, effective slicing method is essential to make ingot technology viable for photovoltaics in terrestrial applications. The fixed abrasive slicing technique (FAST) combines the advantages of the three commercially developed techniques. In its development stage FAST demonstrated cutting effectiveness of 10 cm and 15 cm diameter workpieces. Wire blade development is still the critical element for commercialization of FAST technology. Both impregnated and electroplated wire blades have been developed; techniques have been developed to fix diamonds only in the cutting edge of the wire. Electroplated wires show the most near term promise and this approach is emphasized. With plated wires it has been possible to control the size and shape of the electroplating, it is expected that this feature reduces kerf and prolongs the life of the wirepack.

Operation Reliability Assessment for Cutting Tools by Applying a Proportional Covariate Model to Condition Monitoring Information

PubMed Central

Cai, Gaigai; Chen, Xuefeng; Li, Bing; Chen, Baojia; He, Zhengjia

2012-01-01

The reliability of cutting tools is critical to machining precision and production efficiency. The conventional statistic-based reliability assessment method aims at providing a general and overall estimation of reliability for a large population of identical units under given and fixed conditions. However, it has limited effectiveness in depicting the operational characteristics of a cutting tool. To overcome this limitation, this paper proposes an approach to assess the operation reliability of cutting tools. A proportional covariate model is introduced to construct the relationship between operation reliability and condition monitoring information. The wavelet packet transform and an improved distance evaluation technique are used to extract sensitive features from vibration signals, and a covariate function is constructed based on the proportional covariate model. Ultimately, the failure rate function of the cutting tool being assessed is calculated using the baseline covariate function obtained from a small sample of historical data. Experimental results and a comparative study show that the proposed method is effective for assessing the operation reliability of cutting tools. PMID:23201980

Short Lingual Osteotomy Using a Piezosurgery Ultrasonic Bone-Cutting Device During Sagittal Split Ramus Osteotomy.

PubMed

Kawase-Koga, Yoko; Mori, Yoshiyuki; Kanno, Yuki; Hoshi, Kazuto; Takato, Tsuyoshi

2015-10-01

Short lingual osteotomy is a useful method for the performance of sagittal split ramus osteotomy involving interference between the proximal and distal bone fragments when lateral differences exist in the setback distance. However, this procedure occasionally results in abnormal fracture and nerve injury; expert surgical skill is thus required. We herein describe a novel technique involving the use of an ultrasonic bone-cutting device (Piezosurgery; Mectron Medical Technology, Carasco, Italy) for vertical osteotomy posterior to the mandibular foramen. Successful short lingual osteotomy was performed using this technique with avoidance of abnormal fracture and neurovascular bundle damage.

Detection of Cutting Tool Wear using Statistical Analysis and Regression Model

NASA Astrophysics Data System (ADS)

Ghani, Jaharah A.; Rizal, Muhammad; Nuawi, Mohd Zaki; Haron, Che Hassan Che; Ramli, Rizauddin

2010-10-01

This study presents a new method for detecting the cutting tool wear based on the measured cutting force signals. A statistical-based method called Integrated Kurtosis-based Algorithm for Z-Filter technique, called I-kaz was used for developing a regression model and 3D graphic presentation of I-kaz 3D coefficient during machining process. The machining tests were carried out using a CNC turning machine Colchester Master Tornado T4 in dry cutting condition. A Kistler 9255B dynamometer was used to measure the cutting force signals, which were transmitted, analyzed, and displayed in the DasyLab software. Various force signals from machining operation were analyzed, and each has its own I-kaz 3D coefficient. This coefficient was examined and its relationship with flank wear lands (VB) was determined. A regression model was developed due to this relationship, and results of the regression model shows that the I-kaz 3D coefficient value decreases as tool wear increases. The result then is used for real time tool wear monitoring.

Membrane technology for treating of waste nanofluids coolant: A review

NASA Astrophysics Data System (ADS)

Mohruni, Amrifan Saladin; Yuliwati, Erna; Sharif, Safian; Ismail, Ahmad Fauzi

2017-09-01

The treatment of cutting fluids wastes concerns a big number of industries, especially from the machining operations to foster environmental sustainability. Discharging cutting fluids, waste through separation technique could protect the environment and also human health in general. Several methods for the separation emulsified oils or oily wastewater have been proposed as three common methods, namely chemical, physicochemical and mechanical and membrane technology application. Membranes are used into separate and concentrate the pollutants in oily wastewater through its perm-selectivity. Meanwhile, the desire to compensate for the shortcomings of the cutting fluid media in a metal cutting operation led to introduce the using of nanofluids (NFs) in the minimum quantity lubricant (MQL) technique. NFs are prepared based on nanofluids technology by dispersing nanoparticles (NPs) in liquids. These fluids have potentially played to enhance the performance of traditional heat transfer fluids. Few researchers have studied investigation of the physical-chemical, thermo-physical and heat transfer characteristics of NFs for heat transfer applications. The use of minimum quantity lubrication (MQL) technique by NFs application is developed in many metal cutting operations. MQL did not only serve as a better alternative to flood cooling during machining operation and also increases better-finished surface, reduces impact loads on the environment and fosters environmental sustainability. Waste coolant filtration from cutting tools using membrane was treated by the pretreated process, coagulation technique and membrane filtration. Nanomaterials are also applied to modify the membrane structure and morphology. Polyvinylidene fluoride (PVDF) is the better choice in coolant wastewater treatment due to its hydrophobicity. Using of polyamide nanofiltration membranes BM-20D and UF-PS-100-100, 000, it resulted in the increase of permeability of waste coolant filtration. Titanium dioxide is nanomaterials additive to modify the Nanopores of the surface membrane. Contact angle and average pore size were used in the investigation of the surface morphology of membranes. An adequate choice in modifying the membrane surface in waste coolant filtration may bring a promised alternative as a solution in waste coolant remediation.

Comparing Approaches to Optimize Cut-off Scores for Short Cognitive Screening Instruments in Mild Cognitive Impairment and Dementia

PubMed Central

O’Caoimh, Rónán; Gao, Yang; Svendovski, Anton; Gallagher, Paul; Eustace, Joseph; Molloy, D. William

2017-01-01

Background: Although required to improve the usability of cognitive screening instruments (CSIs), the use of cut-off scores is controversial yet poorly researched. Objective: To explore cut-off scores for two short CSIs: the Standardized Mini-Mental State Examination (SMMSE) and Quick Mild Cognitive Impairment (Qmci) screen, describing adjustments in scores for diagnosis (MCI or dementia), age (≤, >75 years), and education (<, ≥12 years), comparing two methods: the maximal accuracy approach, derived from receiver operating characteristic curves, and Youden’s Index. Methods: Pooled analysis of assessments from patients attending memory clinics in Canada between 1999–2010 : 766 with mild cognitive impairment (MCI) and 1,746 with dementia, and 875 normal controls. Results: The Qmci was more accurate than the SMMSE in differentiating controls from MCI or cognitive impairment (MCI and dementia). Employing the maximal accuracy approach, the optimal SMMSE cut-off for cognitive impairment was <28/30 (AUC 0.86, sensitivity 74%, specificity 88%) versus <63/100 for the Qmci (AUC 0.93, sensitivity 85%, specificity 85%). Using Youden’s Index, the optimal SMMSE cut-off remained <28/30 but fell slightly to <62/100 for the Qmci (sensitivity 83%, specificity 87%). The optimal cut-off for MCI was <29/30 for the SMMSE and <67/100 for the Qmci, irrespective of technique. The maximal accuracy approach generally produced higher Qmci cut-offs than Youden’s Index, both requiring adjustment for age and education. There were no clinically meaningful differences in SMMSE cut-off scores by age and education or method employed. Conclusion: Caution should be exercised selecting cut-offs as these differ by age, education, and method of derivation, with the extent of adjustment varying between CSIs. PMID:28222528

Digital modeling of end-mill cutting tools for FEM applications from the active cutting contour

NASA Astrophysics Data System (ADS)

Salguero, Jorge; Marcos, M.; Batista, M.; Gómez, A.; Mayuet, P.; Bienvenido, R.

2012-04-01

A very current technique in the research field of machining by material removal is the use of simulations using the Finite Element Method (FEM). Nevertheless, and although is widely used in processes that allows approximations to orthogonal cutting, such as shaping, is scarcely used in more complexes processes, such as milling. This fact is due principally to the complex geometry of the cutting tools in these processes, and the need to realize the studi es in an oblique cutting configuration. This paper shows a methodology for the geometrical characterization of commercial endmill cutting tools, by the extraction of the cutting tool contour, making use of optical metrology, and using this geometry to model the active cutting zone with a 3D CAD software. This model is easily exportable to different CAD formats, such as IGES or STEP, and importable from FEM software, where is possible to study the behavior in service of the same ones.

A Technical Approach to Marking Explosives, Propellants, and Precursor Chemicals

DTIC Science & Technology

1998-08-01

polymerase chain reaction (PCR) methods whereby small strands are cut and analyzed under specified temperature mediated enzymatic /molecular reactions (4...such as these are often overlooked. Several other companies have been investigating other methods including immunoassay techniques, microencapsulated

Gradual cut detection using low-level vision for digital video

NASA Astrophysics Data System (ADS)

Lee, Jae-Hyun; Choi, Yeun-Sung; Jang, Ok-bae

1996-09-01

Digital video computing and organization is one of the important issues in multimedia system, signal compression, or database. Video should be segmented into shots to be used for identification and indexing. This approach requires a suitable method to automatically locate cut points in order to separate shot in a video. Automatic cut detection to isolate shots in a video has received considerable attention due to many practical applications; our video database, browsing, authoring system, retrieval and movie. Previous studies are based on a set of difference mechanisms and they measured the content changes between video frames. But they could not detect more special effects which include dissolve, wipe, fade-in, fade-out, and structured flashing. In this paper, a new cut detection method for gradual transition based on computer vision techniques is proposed. And then, experimental results applied to commercial video are presented and evaluated.

Phase unwrapping with graph cuts optimization and dual decomposition acceleration for 3D high-resolution MRI data.

PubMed

Dong, Jianwu; Chen, Feng; Zhou, Dong; Liu, Tian; Yu, Zhaofei; Wang, Yi

2017-03-01

Existence of low SNR regions and rapid-phase variations pose challenges to spatial phase unwrapping algorithms. Global optimization-based phase unwrapping methods are widely used, but are significantly slower than greedy methods. In this paper, dual decomposition acceleration is introduced to speed up a three-dimensional graph cut-based phase unwrapping algorithm. The phase unwrapping problem is formulated as a global discrete energy minimization problem, whereas the technique of dual decomposition is used to increase the computational efficiency by splitting the full problem into overlapping subproblems and enforcing the congruence of overlapping variables. Using three dimensional (3D) multiecho gradient echo images from an agarose phantom and five brain hemorrhage patients, we compared this proposed method with an unaccelerated graph cut-based method. Experimental results show up to 18-fold acceleration in computation time. Dual decomposition significantly improves the computational efficiency of 3D graph cut-based phase unwrapping algorithms. Magn Reson Med 77:1353-1358, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

The use of water-jetting technology in prostheses revision surgery-first results of parameter studies on bone and bone cement.

PubMed

Honl, M; Rentzsch, R; Müller, G; Brandt, C; Bluhm, A; Hille, E; Louis, H; Morlock, M

2000-01-01

Water-jet cutting techniques have been used in industrial applications for many different materials. Recently these techniques have been developed into a revolutionary cutting tool for soft tissues in visceral surgery. The present study investigates the usage of this cutting technology for the revision surgery of endoprostheses. In the first part of the study, samples of bovine bone and acrylic bone cement (PMMA) were cut using an industrial jet cutting device with pure water. Below 400 bar, only PMMA was cut; above 400 bar, bone was also cut, but only pressures above 800 bar resulted in clinically useful rates of material removal (cut depth 2. 4 mm at 10 mm/min traverse speed). In the second part of the study, the effect of adding biocompatible abrasives to the water in order to reduce the required pressure was investigated, resulting in a significantly higher removal of material. At 600 bar, PMMA was cut 5. 2 mm deep with plain water and 15.2 mm deep with added abrasives. The quality of the cuts was increased by the abrasive. Though there was no clear selectivity between bone and PMMA any more, the rate of material removal at similar pressures was significantly higher for PMMA than for bone (600 bar: 1.6 mm cut depth for bone samples, 15.2 mm for PMMA). The measured cut depths with either method were not influenced by a change of the cutting direction with respect to the main direction of the osteons in the bone. However, a reduction of the jet surface angle (90 degrees to 23 degrees ) resulted for bone in a significantly lower cut depth at 600 bar (plain water: 0.62 mm vs. 0.06 mm; abrasive: 1.61 mm vs. 0.60 mm). The laboratory experiments indicate that abrasive water jets may be suitable for cutting biomaterials like bone and bone cement. Copyright 2000 John Wiley & Sons, Inc.

Exploring JLA supernova data with improved flux-averaging technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Shuang; Wen, Sixiang; Li, Miao, E-mail: wangshuang@mail.sysu.edu.cn, E-mail: wensx@mail2.sysu.edu.cn, E-mail: limiao9@mail.sysu.edu.cn

2017-03-01

In this work, we explore the cosmological consequences of the ''Joint Light-curve Analysis'' (JLA) supernova (SN) data by using an improved flux-averaging (FA) technique, in which only the type Ia supernovae (SNe Ia) at high redshift are flux-averaged. Adopting the criterion of figure of Merit (FoM) and considering six dark energy (DE) parameterizations, we search the best FA recipe that gives the tightest DE constraints in the ( z {sub cut}, Δ z ) plane, where z {sub cut} and Δ z are redshift cut-off and redshift interval of FA, respectively. Then, based on the best FA recipe obtained, wemore » discuss the impacts of varying z {sub cut} and varying Δ z , revisit the evolution of SN color luminosity parameter β, and study the effects of adopting different FA recipe on parameter estimation. We find that: (1) The best FA recipe is ( z {sub cut} = 0.6, Δ z =0.06), which is insensitive to a specific DE parameterization. (2) Flux-averaging JLA samples at z {sub cut} ≥ 0.4 will yield tighter DE constraints than the case without using FA. (3) Using FA can significantly reduce the redshift-evolution of β. (4) The best FA recipe favors a larger fractional matter density Ω {sub m} . In summary, we present an alternative method of dealing with JLA data, which can reduce the systematic uncertainties of SNe Ia and give the tighter DE constraints at the same time. Our method will be useful in the use of SNe Ia data for precision cosmology.« less

A Review of Interface Electronic Systems for AT-cut Quartz Crystal Microbalance Applications in Liquids

PubMed Central

Arnau, Antonio

2008-01-01

From the first applications of AT-cut quartz crystals as sensors in solutions more than 20 years ago, the so-called quartz crystal microbalance (QCM) sensor is becoming into a good alternative analytical method in a great deal of applications such as biosensors, analysis of biomolecular interactions, study of bacterial adhesion at specific interfaces, pathogen and microorganism detection, study of polymer film-biomolecule or cell-substrate interactions, immunosensors and an extensive use in fluids and polymer characterization and electrochemical applications among others. The appropriate evaluation of this analytical method requires recognizing the different steps involved and to be conscious of their importance and limitations. The first step involved in a QCM system is the accurate and appropriate characterization of the sensor in relation to the specific application. The use of the piezoelectric sensor in contact with solutions strongly affects its behavior and appropriate electronic interfaces must be used for an adequate sensor characterization. Systems based on different principles and techniques have been implemented during the last 25 years. The interface selection for the specific application is important and its limitations must be known to be conscious of its suitability, and for avoiding the possible error propagation in the interpretation of results. This article presents a comprehensive overview of the different techniques used for AT-cut quartz crystal microbalance in in-solution applications, which are based on the following principles: network or impedance analyzers, decay methods, oscillators and lock-in techniques. The electronic interfaces based on oscillators and phase-locked techniques are treated in detail, with the description of different configurations, since these techniques are the most used in applications for detection of analytes in solutions, and in those where a fast sensor response is necessary. PMID:27879713

Use of the piezosurgery technique for cutting bones in the autotransplantation of unerupted third molars.

PubMed

Koszowski, Rafał; Morawiec, Tadeusz; Bubiłek-Bogacz, Anna

2013-01-01

Autotransplantation is a well-known method used in oral surgery. However, risk of failure, most commonly resulting from root resorption of the transplanted tooth or ankylosis, is quite high. Piezosurgery with specific device tip vibration frequencies enables selective tissue cutting, and therefore, tooth buds or teeth can easily be removed from bones with little injury to periodontal fibers or bud follicles.

"Grinding" cavities in polyurethane foam

NASA Technical Reports Server (NTRS)

Brower, J. R.; Davey, R. E.; Dixon, W. F.; Robb, P. H.; Zebus, P. P.

1980-01-01

Grinding tool installed on conventional milling machine cuts precise cavities in foam blocks. Method is well suited for prototype or midsize production runs and can be adapted to computer control for mass production. Method saves time and materials compared to bonding or hot wire techniques.

On determining the most appropriate test cut-off value: the case of tests with continuous results

PubMed Central

Habibzadeh, Parham; Yadollahie, Mahboobeh

2016-01-01

There are several criteria for determination of the most appropriate cut-off value in a diagnostic test with continuous results. Mostly based on receiver operating characteristic (ROC) analysis, there are various methods to determine the test cut-off value. The most common criteria are the point on ROC curve where the sensitivity and specificity of the test are equal; the point on the curve with minimum distance from the left-upper corner of the unit square; and the point where the Youden’s index is maximum. There are also methods mainly based on Bayesian decision analysis. Herein, we show that a proposed method that maximizes the weighted number needed to misdiagnose, an index of diagnostic test effectiveness we previously proposed, is the most appropriate technique compared to the aforementioned ones. For determination of the cut-off value, we need to know the pretest probability of the disease of interest as well as the costs incurred by misdiagnosis. This means that even for a certain diagnostic test, the cut-off value is not universal and should be determined for each region and for each disease condition. PMID:27812299

Application of the Finite Element Method to Reveal the Causes of Loss of Planeness of Hot-Rolled Steel Sheets during Laser Cutting

NASA Astrophysics Data System (ADS)

Garber, E. A.; Bolobanova, N. L.; Trusov, K. A.

2018-01-01

A finite element technique is developed to simulate the stresses and the strains during strip flattening to reveal the causes of the cutting-assisted loss of planeness of hot-rolled steel sheets processed in roller levelers. The loss of planeness is found to be caused by a nonuniform distribution of the flattening-induced longitudinal tensile stresses over the strip thickness and width. The application of tensile forces to a strip in a roller leveler decreases this nonuniformity and prevents loss of planeness in cutting.

Lathe-cut hydrophilic contact lenses: report of 100 clinical cases.

PubMed

Espy, J W

1978-10-01

In a review of the literature, it became apparent that there were very few articles describing the advantages, as well as the fitting techniques, of lathe-cut hydrophilic contact lenses. Few practitioners, including those who fit other types of hydrophilic lenses and hard lenses, have had any experience with this lens, and considerable interest has been generated by fragmentary reports of good results. This paper describes in detail the geometry of the first lathe-cut hydrophilic lens approved by the Federal Drug Administration, the fitting methods utilizing trial lenses, and the results of 100 patients successfully fitted.

Laser speckle technique to study the effect of chemical pre-treatment on the quality of minimally processed apples

NASA Astrophysics Data System (ADS)

Minz, Preeti D.; Nirala, A. K.

2016-04-01

In the present study, the laser speckle technique has been used for the quality evaluation of chemically treated cut apples. Chemical pre-treatment includes 1% (w/v) solution of citric acid (CA), sodium chloride (SC), and a combination of CA and sodium chloride (CS). The variation in weight loss, respiration rate, total soluble solids (TSS), titratable acidity (TA), and absorbance of chemically treated cut apples stored at 5 °C was monitored for 11 d. The speckle grain size was calculated by an autocovariance method from the speckled images of freshly cut chemically treated apples. The effect of chemicals on TSS and the TA content variation of the cut apples were well correlated to the linear speckle grain size. Circular degree of polarization confirms the presence of a small scatterer and hence Rayleigh diffusion region. For all the treated cut apples, a decrease in the concentration of small particles nearly after the mid-period of storage results in the fast decay of circular degree of polarization. For non-invasive and fast analysis of the chemical constituent of fruits during minimal processing, the laser speckle can be practically used in the food industry.

Modeling of tool path for the CNC sheet cutting machines

NASA Astrophysics Data System (ADS)

Petunin, Aleksandr A.

2015-11-01

In the paper the problem of tool path optimization for CNC (Computer Numerical Control) cutting machines is considered. The classification of the cutting techniques is offered. We also propose a new classification of toll path problems. The tasks of cost minimization and time minimization for standard cutting technique (Continuous Cutting Problem, CCP) and for one of non-standard cutting techniques (Segment Continuous Cutting Problem, SCCP) are formalized. We show that the optimization tasks can be interpreted as discrete optimization problem (generalized travel salesman problem with additional constraints, GTSP). Formalization of some constraints for these tasks is described. For the solution GTSP we offer to use mathematical model of Prof. Chentsov based on concept of a megalopolis and dynamic programming.

Underground Mining Method Selection Using WPM and PROMETHEE

NASA Astrophysics Data System (ADS)

Balusa, Bhanu Chander; Singam, Jayanthu

2018-04-01

The aim of this paper is to represent the solution to the problem of selecting suitable underground mining method for the mining industry. It is achieved by using two multi-attribute decision making techniques. These two techniques are weighted product method (WPM) and preference ranking organization method for enrichment evaluation (PROMETHEE). In this paper, analytic hierarchy process is used for weight's calculation of the attributes (i.e. parameters which are used in this paper). Mining method selection depends on physical parameters, mechanical parameters, economical parameters and technical parameters. WPM and PROMETHEE techniques have the ability to consider the relationship between the parameters and mining methods. The proposed techniques give higher accuracy and faster computation capability when compared with other decision making techniques. The proposed techniques are presented to determine the effective mining method for bauxite mine. The results of these techniques are compared with methods used in the earlier research works. The results show, conventional cut and fill method is the most suitable mining method.

Study on Platinum Coating Depth in Focused Ion Beam Diamond Cutting Tool Milling and Methods for Removing Platinum Layer.

PubMed

Choi, Woong Kirl; Baek, Seung Yub

2015-09-22

In recent years, nanomachining has attracted increasing attention in advanced manufacturing science and technologies as a value-added processes to control material structures, components, devices, and nanoscale systems. To make sub-micro patterns on these products, micro/nanoscale single-crystal diamond cutting tools are essential. Popular non-contact methods for the macro/micro processing of diamond composites are pulsed laser ablation (PLA) and electric discharge machining (EDM). However, for manufacturing nanoscale diamond tools, these machining methods are not appropriate. Despite diamond's extreme physical properties, diamond can be micro/nano machined relatively easily using a focused ion beam (FIB) technique. In the FIB milling process, the surface properties of the diamond cutting tool is affected by the amorphous damage layer caused by the FIB gallium ion collision and implantation and these influence the diamond cutting tool edge sharpness and increase the processing procedures. To protect the diamond substrate, a protection layer-platinum (Pt) coating is essential in diamond FIB milling. In this study, the depth of Pt coating layer which could decrease process-induced damage during FIB fabrication is investigated, along with methods for removing the Pt coating layer on diamond tools. The optimum Pt coating depth has been confirmed, which is very important for maintaining cutting tool edge sharpness and decreasing processing procedures. The ultra-precision grinding method and etching with aqua regia method have been investigated for removing the Pt coating layer. Experimental results show that when the diamond cutting tool width is bigger than 500 nm, ultra-precision grinding method is appropriate for removing Pt coating layer on diamond tool. However, the ultra-precision grinding method is not recommended for removing the Pt coating layer when the cutting tool width is smaller than 500 nm, because the possibility that the diamond cutting tool is damaged by the grinding process will be increased. Despite the etching method requiring more procedures to remove the Pt coating layer after FIB milling, it is a feasible method for diamond tools with under 500 nm width.

Modelling of tunnelling processes and rock cutting tool wear with the particle finite element method

NASA Astrophysics Data System (ADS)

Carbonell, Josep Maria; Oñate, Eugenio; Suárez, Benjamín

2013-09-01

Underground construction involves all sort of challenges in analysis, design, project and execution phases. The dimension of tunnels and their structural requirements are growing, and so safety and security demands do. New engineering tools are needed to perform a safer planning and design. This work presents the advances in the particle finite element method (PFEM) for the modelling and the analysis of tunneling processes including the wear of the cutting tools. The PFEM has its foundation on the Lagrangian description of the motion of a continuum built from a set of particles with known physical properties. The method uses a remeshing process combined with the alpha-shape technique to detect the contacting surfaces and a finite element method for the mechanical computations. A contact procedure has been developed for the PFEM which is combined with a constitutive model for predicting the excavation front and the wear of cutting tools. The material parameters govern the coupling of frictional contact and wear between the interacting domains at the excavation front. The PFEM allows predicting several parameters which are relevant for estimating the performance of a tunnelling boring machine such as wear in the cutting tools, the pressure distribution on the face of the boring machine and the vibrations produced in the machinery and the adjacent soil/rock. The final aim is to help in the design of the excavating tools and in the planning of the tunnelling operations. The applications presented show that the PFEM is a promising technique for the analysis of tunnelling problems.

Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP crystals

NASA Astrophysics Data System (ADS)

Zhang, F. H.; Wang, S. F.; An, C. H.; Wang, J.; Xu, Q.

2017-06-01

Large-aperture potassium dihydrogen phosphate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machining errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China.

On making cuts for magnetic scalar potentials in multiply connected regions

NASA Astrophysics Data System (ADS)

Kotiuga, P. R.

1987-04-01

The problem of making cuts is of importance to scalar potential formulations of three-dimensional eddy current problems. Its heuristic solution has been known for a century [J. C. Maxwell, A Treatise on Electricity and Magnetism, 3rd ed. (Clarendon, Oxford, 1981), Chap. 1, Article 20] and in the last decade, with the use of finite element methods, a restricted combinatorial variant has been proposed and solved [M. L. Brown, Int. J. Numer. Methods Eng. 20, 665 (1984)]. This problem, in its full generality, has never received a rigorous mathematical formulation. This paper presents such a formulation and outlines a rigorous proof of existence. The technique used in the proof expose the incredible intricacy of the general problem and the restrictive assumptions of Brown [Int. J. Numer. Methods Eng. 20, 665 (1984)]. Finally, the results make rigorous Kotiuga's (Ph. D. Thesis, McGill University, Montreal, 1984) heuristic interpretation of cuts and duality theorems via intersection matrices.

An evaluation of alternative reactor vessel cutting technologies for the experimental boiling water reactor at Argonne National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boing, L.E.; Henley, D.R.; Manion, W.J.

1989-12-01

Metal cutting techniques that can be used to segment the reactor pressure vessel of the Experimental Boiling Water Reactor (EBWR) at Argonne National Laboratory (ANL) have been evaluated by Nuclear Energy Services. Twelve cutting technologies are described in terms of their ability to perform the required task, their performance characteristics, environmental and radiological impacts, and cost and schedule considerations. Specific recommendations regarding which technology should ultimately be used by ANL are included. The selection of a cutting method was the responsibility of the decommissioning staff at ANL, who included a relative weighting of the parameters described in this document inmore » their evaluation process. 73 refs., 26 figs., 69 tabs.« less

Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside Diameter (I.D.) saws

NASA Technical Reports Server (NTRS)

Aharonyan, P.

1980-01-01

Modifications to a 16 inch STC automated saw included: a programmable feed system; a crystal rotating system; and a STC dynatrack blade boring and control system. By controlling the plating operation and by grinding the cutting edge, 16 inch I.D. blades were produced with a cutting edge thickness of .22 mm. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge I.D. slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

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.

Efficient prepreg recycling at low temperatures

NASA Astrophysics Data System (ADS)

Pannkoke, Kord; Oethe, Marcus; Busse, Jürgen

When manufacturing fibre reinforced plastics engineers are still confronted with a lack of experience concerning efficient recycling methods for prepreg cutting waste. Normally, the prepregs are cured and subsequently milled to use them as a filler material for polymers. However, this method is expensive and it is difficult to find applications for the milled FRP. An alternative method to recycle CFRP prepregs will be presented in this paper. Cutting the uncured prepreg waste was done by means of a saw mill which was cooled down to low temperatures. Working temperatures of -30°C are sufficient to harden the uncured resin and to achieve cuttable prepregs. Furthermore, post-curing during the cutting process is avoided with this technique. The result is a `cotton'-like matted structure with random fibre orientation and fibre length distribution. Subsequent curing was done by means of a press and an autoclave, respectively. It will be shown by means of tension and bending tests that low-temperature cutting of uncured prepregs is a way to partly conserve the high valuation of FRP during recycling. Furthermore, it offers possibilities for various applications.

Large-scale fabrication of micro-lens array by novel end-fly-cutting-servo diamond machining.

PubMed

Zhu, Zhiwei; To, Suet; Zhang, Shaojian

2015-08-10

Fast/slow tool servo (FTS/STS) diamond turning is a very promising technique for the generation of micro-lens array (MLA). However, it is still a challenge to process MLA in large scale due to certain inherent limitations of this technique. In the present study, a novel ultra-precision diamond cutting method, as the end-fly-cutting-servo (EFCS) system, is adopted and investigated for large-scale generation of MLA. After a detailed discussion of the characteristic advantages for processing MLA, the optimal toolpath generation strategy for the EFCS is developed with consideration of the geometry and installation pose of the diamond tool. A typical aspheric MLA over a large area is experimentally fabricated, and the resulting form accuracy, surface micro-topography and machining efficiency are critically investigated. The result indicates that the MLA with homogeneous quality over the whole area is obtained. Besides, high machining efficiency, extremely small volume of control points for the toolpath, and optimal usage of system dynamics of the machine tool during the whole cutting can be simultaneously achieved.

Approximate ground states of the random-field Potts model from graph cuts

NASA Astrophysics Data System (ADS)

Kumar, Manoj; Kumar, Ravinder; Weigel, Martin; Banerjee, Varsha; Janke, Wolfhard; Puri, Sanjay

2018-05-01

While the ground-state problem for the random-field Ising model is polynomial, and can be solved using a number of well-known algorithms for maximum flow or graph cut, the analog random-field Potts model corresponds to a multiterminal flow problem that is known to be NP-hard. Hence an efficient exact algorithm is very unlikely to exist. As we show here, it is nevertheless possible to use an embedding of binary degrees of freedom into the Potts spins in combination with graph-cut methods to solve the corresponding ground-state problem approximately in polynomial time. We benchmark this heuristic algorithm using a set of quasiexact ground states found for small systems from long parallel tempering runs. For a not-too-large number q of Potts states, the method based on graph cuts finds the same solutions in a fraction of the time. We employ the new technique to analyze the breakup length of the random-field Potts model in two dimensions.

Characterization of particulate emissions from Australian open-cut coal mines: Toward improved emission estimates.

PubMed

Richardson, Claire; Rutherford, Shannon; Agranovski, Igor

2018-06-01

Given the significance of mining as a source of particulates, accurate characterization of emissions is important for the development of appropriate emission estimation techniques for use in modeling predictions and to inform regulatory decisions. The currently available emission estimation methods for Australian open-cut coal mines relate primarily to total suspended particulates and PM 10 (particulate matter with an aerodynamic diameter <10 μm), and limited data are available relating to the PM 2.5 (<2.5 μm) size fraction. To provide an initial analysis of the appropriateness of the currently available emission estimation techniques, this paper presents results of sampling completed at three open-cut coal mines in Australia. The monitoring data demonstrate that the particulate size fraction varies for different mining activities, and that the region in which the mine is located influences the characteristics of the particulates emitted to the atmosphere. The proportion of fine particulates in the sample increased with distance from the source, with the coarse fraction being a more significant proportion of total suspended particulates close to the source of emissions. In terms of particulate composition, the results demonstrate that the particulate emissions are predominantly sourced from naturally occurring geological material, and coal comprises less than 13% of the overall emissions. The size fractionation exhibited by the sampling data sets is similar to that adopted in current Australian emission estimation methods but differs from the size fractionation presented in the U.S. Environmental Protection Agency methodology. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for use in modeling predictions. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for use in modeling predictions. Comprehensive air quality monitoring was undertaken, and corresponding recommendations were provided.

Optimization of Interior Permanent Magnet Motor by Quality Engineering and Multivariate Analysis

NASA Astrophysics Data System (ADS)

Okada, Yukihiro; Kawase, Yoshihiro

This paper has described the method of optimization based on the finite element method. The quality engineering and the multivariable analysis are used as the optimization technique. This optimizing method consists of two steps. At Step.1, the influence of parameters for output is obtained quantitatively, at Step.2, the number of calculation by the FEM can be cut down. That is, the optimal combination of the design parameters, which satisfies the required characteristic, can be searched for efficiently. In addition, this method is applied to a design of IPM motor to reduce the torque ripple. The final shape can maintain average torque and cut down the torque ripple 65%. Furthermore, the amount of permanent magnets can be reduced.

Integrand-level reduction of loop amplitudes by computational algebraic geometry methods

NASA Astrophysics Data System (ADS)

Zhang, Yang

2012-09-01

We present an algorithm for the integrand-level reduction of multi-loop amplitudes of renormalizable field theories, based on computational algebraic geometry. This algorithm uses (1) the Gröbner basis method to determine the basis for integrand-level reduction, (2) the primary decomposition of an ideal to classify all inequivalent solutions of unitarity cuts. The resulting basis and cut solutions can be used to reconstruct the integrand from unitarity cuts, via polynomial fitting techniques. The basis determination part of the algorithm has been implemented in the Mathematica package, BasisDet. The primary decomposition part can be readily carried out by algebraic geometry softwares, with the output of the package BasisDet. The algorithm works in both D = 4 and D = 4 - 2 ɛ dimensions, and we present some two and three-loop examples of applications of this algorithm.

The evaluation of the optimization design and application effect of same-well-injection-production technique’s injection-production circulatory system

NASA Astrophysics Data System (ADS)

Guoxing, Zheng; Minghu, Jiang; Hongliang, Gong; Nannan, Zhang; Jianguang, Wei

2018-02-01

According to basic principles of combining series of strata and demands of same-well injection-production technique, the optimization designing method of same-well injection-production technique’s injection-production circulatory system is given. Based on oil-water two-phase model with condition of arbitrarily well network, a dynamic forecast method for the application of same-well injection-production reservoir is established with considering the demands and capacity of same-well injection-production technique, sample wells are selected to launch the forecast evaluation and analysis of same-well injection-production reservoir application’s effect. Results show: single-test-well composite water cut decreases by 4.7% and test-well-group composite water cut decreases by 1.56% under the condition of basically invariant ground water injection rate. The method provides theoretical support for the proof of same-well injection-production technique’s reservoir development improving effect and further tests.

Nano Mechanical Machining Using AFM Probe

NASA Astrophysics Data System (ADS)

Mostofa, Md. Golam

Complex miniaturized components with high form accuracy will play key roles in the future development of many products, as they provide portability, disposability, lower material consumption in production, low power consumption during operation, lower sample requirements for testing, and higher heat transfer due to their very high surface-to-volume ratio. Given the high market demand for such micro and nano featured components, different manufacturing methods have been developed for their fabrication. Some of the common technologies in micro/nano fabrication are photolithography, electron beam lithography, X-ray lithography and other semiconductor processing techniques. Although these methods are capable of fabricating micro/nano structures with a resolution of less than a few nanometers, some of the shortcomings associated with these methods, such as high production costs for customized products, limited material choices, necessitate the development of other fabricating techniques. Micro/nano mechanical machining, such an atomic force microscope (AFM) probe based nano fabrication, has, therefore, been used to overcome some the major restrictions of the traditional processes. This technique removes material from the workpiece by engaging micro/nano size cutting tool (i.e. AFM probe) and is applicable on a wider range of materials compared to the photolithographic process. In spite of the unique benefits of nano mechanical machining, there are also some challenges with this technique, since the scale is reduced, such as size effects, burr formations, chip adhesions, fragility of tools and tool wear. Moreover, AFM based machining does not have any rotational movement, which makes fabrication of 3D features more difficult. Thus, vibration-assisted machining is introduced into AFM probe based nano mechanical machining to overcome the limitations associated with the conventional AFM probe based scratching method. Vibration-assisted machining reduced the cutting forces and burr formations through intermittent cutting. Combining the AFM probe based machining with vibration-assisted machining enhanced nano mechanical machining processes by improving the accuracy, productivity and surface finishes. In this study, several scratching tests are performed with a single crystal diamond AFM probe to investigate the cutting characteristics and model the ploughing cutting forces. Calibration of the probe for lateral force measurements, which is essential, is also extended through the force balance method. Furthermore, vibration-assisted machining system is developed and applied to fabricate different materials to overcome some of the limitations of the AFM probe based single point nano mechanical machining. The novelty of this study includes the application of vibration-assisted AFM probe based nano scale machining to fabricate micro/nano scale features, calibration of an AFM by considering different factors, and the investigation of the nano scale material removal process from a different perspective.

Drill hole logging with infrared spectroscopy

USGS Publications Warehouse

Calvin, W.M.; Solum, J.G.

2005-01-01

Infrared spectroscopy has been used to identify rocks and minerals for over 40 years. The technique is sensitive to primary silicates as well as alteration products. Minerals can be uniquely identified based on multiple absorption features at wavelengths from the visible to the thermal infrared. We are currently establishing methods and protocols in order to use the technique for rapid assessment of downhole lithology on samples obtained during drilling operations. Initial work performed includes spectral analysis of chip cuttings and core sections from drill sites around Desert Peak, NV. In this paper, we report on a survey of 10,000 feet of drill cuttings, at 100 foot intervals, from the San Andreas Fault Observatory at Depth (SAFOD). Data from Blue Mountain geothermal wells will also be acquired. We will describe the utility of the technique for rapid assessment of lithologic and mineralogic discrimination.

Cost minimizing of cutting process for CNC thermal and water-jet machines

NASA Astrophysics Data System (ADS)

Tavaeva, Anastasia; Kurennov, Dmitry

2015-11-01

This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

Improved cutback method measuring beat-length for high-birefringence optical fiber by fitting data of photoelectric signal

NASA Astrophysics Data System (ADS)

Shi, Zhi-Dong; Lin, Jian-Qiang; Bao, Huan-Huan; Liu, Shu; Xiang, Xue-Nong

2008-03-01

A photoelectric measurement system for measuring the beat length of birefringence fiber is set up including a set of rotating-wave-plate polarimeter using single photodiode. And two improved cutback methods suitable for measuring beat-length within millimeter range of high birefringence fiber are proposed through data processing technique. The cut length needs not to be restricted shorter than one centimeter so that the auto-cleaving machine is freely used, and no need to carefully operate the manually cleaving blade with low efficiency and poor success. The first method adopts the parameter-fitting to a saw-tooth function of tried beat length by the criterion of minimum square deviations, without special limitation on the cut length. The second method adopts linear-fitting in the divided length ranges, only restrict condition is the increment between different cut lengths less than one beat-length. For a section of holey high-birefringence fiber, we do experiments respectively by the two methods. The detecting error of beat-length is discussed and the advantage is compared.

Mechanical pre-cutting, a rediscovered tunneling technique

NASA Astrophysics Data System (ADS)

van Walsum, E.

1991-04-01

In 1950, the exact outlines of some circular tunnels, to be driven through chalk for the Corps of Engineers' Fort Randall Reservoir Project on the Missouri River at Pickstown, South Dakota, U.S.A., were pre-cut mechanically, i. e. prior to blasting the tunnel openings. No further applications of mechanical pre-cutting as a tunneling technique were made until the technique was rediscovered and further developed in France during the seventies. These further developments relate to the pre-cutting of harder rocks and the pre-cutting of cohesive and non-cohesive soils combined with the construction of a concrete pre-lining, i. e. a lining which is in place before the ground under it is excavated. Mechanical pre-cutting, as presently practiced, improves the quality and safety of tunneling and reduces surface settlement, noise and vibration. It is concluded that the technique is likely to be applied in the future in the construction of various types of underground structures whenever conventional tunneling is too risky or when environmental concerns are important.

Analysis of the learning curve for pre-cut corneal specimens in preparation for lamellar transplantation: a prospective, single-centre, consecutive case series prepared at the Lions New South Wales Eye Bank.

PubMed

Martin, Aifric Isabel; Devasahayam, Rajnesh; Hodge, Christopher; Cooper, Simon; Sutton, Gerard L

2017-09-01

This study is the first paper to establish a learning curve by a single technician. Preparation of pre-cut corneal endothelial grafts commenced at Lions New South Wales Eye Bank in December 2014. The primary objective of this study was to review the safety and reliability of the preparation method during the first year of production. This is a hospital-based, prospective case series. There were 234 consecutive donor corneal lenticules. Donor lenticules were prepared by a single operator using a linear cutting microkeratome. Immediately prior to cutting, central corneal thickness values were recorded. Measurements of the corneal bed were taken immediately following lenticule preparation. Outcomes were separated by blade sizes, and intended thickness was compared to actual thickness for each setting. Early specimens were compared to later ones to assess for a learning curve within the technique. The main parameter measured is the mean difference from intended lamellar cut thickness. The mean final cut thickness was 122.36 ± 20.35 μm, and the mean difference from intended cut was 30.17 ± 37.45 μm. No significant difference was found between results achieved with early specimens versus those achieved with later specimens (P = 0.425). Thin, reproducible endothelial grafts can routinely be produced by trained technicians at their respective eye banks without significant concerns for an extended learning curve. This service can reduce perioperative surgical complexity, required surgical paraphernalia and theatre times. The consistent preparation of single-pass, ultrathin pre-cut corneas may have additional advantages for surgeons seeking to introduce lamellar techniques. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

Piezoelectric osteotomy in hand surgery: first experiences with a new technique

PubMed Central

Hoigne, Dominik J; Stübinger, Stefan; Kaenel, Oliver Von; Shamdasani, Sonia; Hasenboehler, Paula

2006-01-01

Background In hand and spinal surgery nerve lesions are feared complications with the use of standard oscillating saws. Oral surgeons have started using a newly developed ultrasound bone scalpel when performing precise osteotomies. By using a frequency of 25–29 kHz only mineralized tissue is cut, sparing the soft tissue. This reduces the risk of nerve lesions. As there is a lack of experience with this technique in the field of orthopaedic bone surgery, we performed the first ultrasound osteotomy in hand surgery. Method While performing a correctional osteotomy of the 5th metacarpal bone we used the Piezosurgery® Device from Mectron [Italy] instead of the usual oscillating saw. We will report on our experience with one case, with a follow up time of one year. Results The cut was highly precise and there were no vibrations of the bone. The time needed for the operation was slightly longer than the time needed while using the usual saw. Bone healing was good and at no point were there any neurovascular disturbances. Conclusion The Piezosurgery® Device is useful for small long bone osteotomies. Using the fine tip enables curved cutting and provides an opportunity for new osteotomy techniques. As the device selectively cuts bone we feel that this device has great potential in the field of hand- and spinal surgery. PMID:16611362

Structural dynamics payload loads estimates

NASA Technical Reports Server (NTRS)

Engels, R. C.

1982-01-01

Methods for the prediction of loads on large space structures are discussed. Existing approaches to the problem of loads calculation are surveyed. A full scale version of an alternate numerical integration technique to solve the response part of a load cycle is presented, and a set of short cut versions of the algorithm developed. The implementation of these techniques using the software package developed is discussed.

Wear measurement of the cutting edge of superhard turning tools using TLA technique

NASA Astrophysics Data System (ADS)

Vasváry, L.; Ditrói, F.; Takács, S.; Szabó, Z.; Szűcs, J.; Kundrák, J.; Mahunka, I.

1994-03-01

Wear measurement on superhard boron nitride and artificial diamond turning tools was performed using thin layer activation (TLA) technique. The samples were irradiated in two different geometries to improve the sensitivity of the method and change the region of wear to be investigated. The most proper irradiation parameters and nuclear reactions were investigated for both kind of tools.

SU-E-J-252: Reproducibility of Radiogenomic Image Features: Comparison of Two Semi-Automated Segmentation Methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, M; Woo, B; Kim, J

Purpose: Objective and reliable quantification of imaging phenotype is an essential part of radiogenomic studies. We compared the reproducibility of two semi-automatic segmentation methods for quantitative image phenotyping in magnetic resonance imaging (MRI) of glioblastoma multiforme (GBM). Methods: MRI examinations with T1 post-gadolinium and FLAIR sequences of 10 GBM patients were downloaded from the Cancer Image Archive site. Two semi-automatic segmentation tools with different algorithms (deformable model and grow cut method) were used to segment contrast enhancement, necrosis and edema regions by two independent observers. A total of 21 imaging features consisting of area and edge groups were extracted automaticallymore » from the segmented tumor. The inter-observer variability and coefficient of variation (COV) were calculated to evaluate the reproducibility. Results: Inter-observer correlations and coefficient of variation of imaging features with the deformable model ranged from 0.953 to 0.999 and 2.1% to 9.2%, respectively, and the grow cut method ranged from 0.799 to 0.976 and 3.5% to 26.6%, respectively. Coefficient of variation for especially important features which were previously reported as predictive of patient survival were: 3.4% with deformable model and 7.4% with grow cut method for the proportion of contrast enhanced tumor region; 5.5% with deformable model and 25.7% with grow cut method for the proportion of necrosis; and 2.1% with deformable model and 4.4% with grow cut method for edge sharpness of tumor on CE-T1W1. Conclusion: Comparison of two semi-automated tumor segmentation techniques shows reliable image feature extraction for radiogenomic analysis of GBM patients with multiparametric Brain MRI.« less

Biomedical microfluidic devices by using low-cost fabrication techniques: A review.

PubMed

Faustino, Vera; Catarino, Susana O; Lima, Rui; Minas, Graça

2016-07-26

One of the most popular methods to fabricate biomedical microfluidic devices is by using a soft-lithography technique. However, the fabrication of the moulds to produce microfluidic devices, such as SU-8 moulds, usually requires a cleanroom environment that can be quite costly. Therefore, many efforts have been made to develop low-cost alternatives for the fabrication of microstructures, avoiding the use of cleanroom facilities. Recently, low-cost techniques without cleanroom facilities that feature aspect ratios more than 20, for fabricating those SU-8 moulds have been gaining popularity among biomedical research community. In those techniques, Ultraviolet (UV) exposure equipment, commonly used in the Printed Circuit Board (PCB) industry, replaces the more expensive and less available Mask Aligner that has been used in the last 15 years for SU-8 patterning. Alternatively, non-lithographic low-cost techniques, due to their ability for large-scale production, have increased the interest of the industrial and research community to develop simple, rapid and low-cost microfluidic structures. These alternative techniques include Print and Peel methods (PAP), laserjet, solid ink, cutting plotters or micromilling, that use equipment available in almost all laboratories and offices. An example is the xurography technique that uses a cutting plotter machine and adhesive vinyl films to generate the master moulds to fabricate microfluidic channels. In this review, we present a selection of the most recent lithographic and non-lithographic low-cost techniques to fabricate microfluidic structures, focused on the features and limitations of each technique. Only microfabrication methods that do not require the use of cleanrooms are considered. Additionally, potential applications of these microfluidic devices in biomedical engineering are presented with some illustrative examples. Copyright © 2015 Elsevier Ltd. All rights reserved.

Method for Fabricating Composite Structures Using Pultrusion Processing

NASA Technical Reports Server (NTRS)

Farley, Gary L. (Inventor)

2000-01-01

A method for fabricating composite structures at a low-cost, moderate-to-high production rate. A first embodiment of the method includes employing a continuous press forming fabrication process. A second embodiment of the method includes employing a pultrusion process for obtaining composite structures. The methods include coating yarns with matrix material, weaving the yarn into fabric to produce a continuous fabric supply and feeding multiple layers of net-shaped fabrics having optimally oriented fibers into a debulking tool to form an undebulked preform. The continuous press forming fabrication process includes partially debulking the preform, cutting the partially debulked preform and debulking the partially debulked preform to form a net-shape. An electron-beam or similar technique then cures the structure. The pultrusion fabric process includes feeding the undebulked preform into a heated die and gradually debulking the undebulked preform. The undebulked preform in the heated die changes dimension until a desired cross-sectional dimension is achieved. This process further includes obtaining a net-shaped infiltrated uncured preform, cutting the uncured preform to a desired length and electron-beam curing (or similar technique) the uncured preform. These fabrication methods produce superior structures formed at higher production rates, resulting in lower cost and high structural performance.

Method for Fabricating Composite Structures Using Continuous Press Forming

NASA Technical Reports Server (NTRS)

Farley, Gary L. (Inventor)

1997-01-01

A method for fabricating composite structures at a low-cost. moderate-to-high production rate. A first embodiment of the method includes employing a continuous press forming fabrication process. A second embodiment of the method includes employing a pultrusion process for obtaining composite structures. The methods include coating yarns with matrix material, weaving the yarn into fabric to produce a continuous fabric supply and feeding multiple layers of net-shaped fabrics having optimally oriented fibers into a debulking tool to form an undebulked preform. The continuous press forming fabrication process includes partially debulking the preform, cutting the partially debulked preform and debulking the partially debulked preform to form a net-shape. An electron-beam or similar technique then cures the structure. The pultrusion fabric process includes feeding the undebulked preform into a heated die and gradually debulking the undebulked preform. The undebulked preform in the heated die changes dimension until a desired cross-sectional dimension is achieved. This process further includes obtaining a net-shaped infiltrated uncured preform, cutting the uncured preform to a desired length and electron-beam curing (or similar technique) the uncured preform. These fabrication methods produce superior structures formed at higher production rates. resulting in lower cost and high structural performance.

Method for Fabricating Composite Structures Using Pultrusion Processing

NASA Technical Reports Server (NTRS)

Farley, Gary L. (Inventor)

2000-01-01

A method for fabricating composite structures at a low-cost, moderate-to-high production rate. A first embodiment of the method includes employing a continuous press forming fabrication process. A second embodiment of the method includes employing a pultrusion process for obtaining composite structures. The methods include coating yarns with matrix material, weaving the yarn into fabric to produce a continuous fabric supply and feeding multiple layers of net-shaped fabrics having optimally oriented fibers into a debulking tool to form an undebulked preform. The continuous press forming fabrication process includes partially debulking the preform, cutting the partially debulked preform and debulking the partially debulked preform to form a netshape. An electron-beam or similar technique then cures the structure. The pultrusion fabric process includes feeding the undebulked preform into a heated die and gradually debulking the undebulked preform. The undebulked preform in the heated die changes dimension until a desired cross-sectional dimension is achieved. This process further includes obtaining a net-shaped infiltrated uncured preform, cutting the uncured preform to a desired length and electronbeam curing (or similar technique) the uncured preform. These fabrication methods produce superior structures formed at higher production rates, resulting in lower cost and high structural performance.

Fabrication of a wide-field NIR integral field unit for SWIMS using ultra-precision cutting

NASA Astrophysics Data System (ADS)

Kitagawa, Yutaro; Yamagata, Yutaka; Morita, Shin-ya; Motohara, Kentaro; Ozaki, Shinobu; Takahashi, Hidenori; Konishi, Masahiro; Kato, Natsuko M.; Kobayakawa, Yutaka; Terao, Yasunori; Ohashi, Hirofumi

2016-07-01

We describe overview of fabrication methods and measurement results of test fabrications of optical surfaces for an integral field unit (IFU) for Simultaneous color Wide-field Infrared Multi-object Spectrograph, SWIMS, which is a first-generation instrument for the University of Tokyo Atacama Observatory 6.5-m telescope. SWIMS-IFU provides entire near-infrared spectrum from 0.9 to 2.5 μm simultaneously covering wider field of view of 17" × 13" compared with current near-infrared IFUs. We investigate an ultra-precision cutting technique to monolithically fabricate optical surfaces of IFU optics such as an image slicer. Using 4- or 5-axis ultra precision machine we compare the milling process and shaper cutting process to find the best way of fabrication of image slicers. The measurement results show that the surface roughness almost satisfies our requirement in both of two methods. Moreover, we also obtain ideal surface form in the shaper cutting process. This method will be adopted to other mirror arrays (i.e. pupil mirror and slit mirror, and such monolithic fabrications will also help us to considerably reduce alignment procedure of each optical elements.

Simulation of router action on a lathe to test the cutting tool performance in edge-trimming of graphite/epoxy composite

NASA Astrophysics Data System (ADS)

Ramulu, M.; Rogers, E.

1994-04-01

The predominant machining application with graphite/epoxy composite materials in aerospace industry is peripheral trimming. The computer numerically controlled (CNC) high speed routers required to do edge trimming work are generally scheduled for production work in industry and are not available for extensive cutter testing. Therefore, an experimental method of simulating the conditions of periphery trim using a lathe is developed in this paper. The validity of the test technique will be demonstrated by conducting carbide tool wear tests under dry cutting conditions. The experimental results will be analyzed to characterize the wear behavior of carbide cutting tools in machining the composite materials.

Creating a Vision Channel for Observing Deep-Seated Anatomy in Medical Augmented Reality

NASA Astrophysics Data System (ADS)

Wimmer, Felix; Bichlmeier, Christoph; Heining, Sandro M.; Navab, Nassir

The intent of medical Augmented Reality (AR) is to augment the surgeon's real view on the patient with the patient's interior anatomy resulting from a suitable visualization of medical imaging data. This paper presents a fast and user-defined clipping technique for medical AR allowing for cutting away any parts of the virtual anatomy and images of the real part of the AR scene hindering the surgeon's view onto the deepseated region of interest. Modeled on cut-away techniques from scientific illustrations and computer graphics, the method creates a fixed vision channel to the inside of the patient. It enables a clear view on the focussed virtual anatomy and moreover improves the perception of spatial depth.

Thermocouple and infrared sensor-based measurement of temperature distribution in metal cutting.

PubMed

Kus, Abdil; Isik, Yahya; Cakir, M Cemal; Coşkun, Salih; Özdemir, Kadir

2015-01-12

In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.

Thermocouple and Infrared Sensor-Based Measurement of Temperature Distribution in Metal Cutting

PubMed Central

Kus, Abdil; Isik, Yahya; Cakir, M. Cemal; Coşkun, Salih; Özdemir, Kadir

2015-01-01

In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining. PMID:25587976

DECONTAMINATION OF STRUCTURES AND DEBRIS AT SUPERFUND SITES

EPA Science Inventory

Two building decontamination technologies were demonstrated and evaluated: a method for in situ degradation of PCB's requiring application of an alkali metal/polyethylene glycolate mixture directly on concrete surfaces; and a shotblasting technique using steel shot to cut away co...

Retrograde endopyelotomy: a comparison between laser and Acucise balloon cutting catheter.

PubMed

el-Nahas, Ahmed R

2007-03-01

Endopyelotomy and laparoscopic pyeloplasty are the preferred modalities for treatment of ureteropelvic junction obstruction because of their minimally invasive nature. There are continuous efforts for improving endopyelotomy techniques and outcome. Retrograde access represents the natural evolution of endopyelotomy. The Acucise cutting balloon catheter (Applied Medical Resources Corp., Laguna Hills, CA) and ureteroscopic endopyelotomy using holmium laser are the most widely accepted techniques. The Acucise catheter was developed to simplify retrograde endopyelotomy and made it possible for all urologists, regardless of their endourologic skills. The Acucise catheter depends on incision and dilatation of the ureteropelvic junction under fluoroscopic guidance, whereas ureteroscopy allows visual control of the site, depth, and extent of the incision; the holmium laser is a perfect method for a clean precise incision. Review of the English literature showed that the Acucise technique was more widely performed, though laser had better (but not statistically significant) safety and efficacy profiles.

Three-Dimensional Profiles Using a Spherical Cutting Bit: Problem Solving in Practice

ERIC Educational Resources Information Center

Ollerton, Richard L.; Iskov, Grant H.; Shannon, Anthony G.

2002-01-01

An engineering problem concerned with relating the coordinates of the centre of a spherical cutting tool to the actual cutting surface leads to a potentially rich example of problem-solving techniques. Basic calculus, Lagrange multipliers and vector calculus techniques are employed to produce solutions that may be compared to better understand…

Study of mandible reconstruction using a fibula flap with application of additive manufacturing technology

PubMed Central

2014-01-01

Background This study aimed to establish surgical guiding techniques for completing mandible lesion resection and reconstruction of the mandible defect area with fibula sections in one surgery by applying additive manufacturing technology, which can reduce the surgical duration and enhance the surgical accuracy and success rate. Methods A computer assisted mandible reconstruction planning (CAMRP) program was used to calculate the optimal cutting length and number of fibula pieces and design the fixtures for mandible cutting, registration, and arrangement of the fibula segments. The mandible cutting and registering fixtures were then generated using an additive manufacturing system. The CAMRP calculated the optimal fibula cutting length and number of segments based on the location and length of the defective portion of the mandible. The mandible cutting jig was generated according to the boundary surface of the lesion resection on the mandible STL model. The fibular cutting fixture was based on the length of each segment, and the registered fixture was used to quickly arrange the fibula pieces into the shape of the defect area. In this study, the mandibular lesion was reconstructed using registered fibular sections in one step, and the method is very easy to perform. Results and conclusion The application of additive manufacturing technology provided customized models and the cutting fixtures and registered fixtures, which can improve the efficiency of clinical application. This study showed that the cutting fixture helped to rapidly complete lesion resection and fibula cutting, and the registered fixture enabled arrangement of the fibula pieces and allowed completion of the mandible reconstruction in a timely manner. Our method can overcome the disadvantages of traditional surgery, which requires a long and different course of treatment and is liable to cause error. With the help of optimal cutting planning by the CAMRP and the 3D printed mandible resection jig and fibula cutting fixture, this all-in-one process of mandible reconstruction furnishes many benefits in this field by enhancing the accuracy of surgery, shortening the operation duration, reducing the surgical risk, and resulting in a better mandible appearance of the patients after surgery. PMID:24885749

Manual herbicide application methods for managing vegetation in Appalachian hardwood forests

Treesearch

Jeffrey D. Kochenderfer; James N. Kochenderfer; Gary W. Miller

2012-01-01

Four manual herbicide application methods are described for use in Appalachian hardwood forests. Stem injection, basal spray, cut-stump, and foliar spray techniques can be used to control interfering vegetation and promote the development of desirable reproduction and valuable crop trees in hardwood forests. Guidelines are presented to help the user select the...

The Cooling and Lubrication Performance of Graphene Platelets in Micro-Machining Environments

NASA Astrophysics Data System (ADS)

Chu, Bryan

The research presented in this thesis is aimed at investigating the use of graphene platelets (GPL) to address the challenges of excessive tool wear, reduced part quality, and high specific power consumption encountered in micro-machining processes. There are two viable methods of introducing GPL into micro-machining environments, viz., the embedded delivery method, where the platelets are embedded into the part being machined, and the external delivery method, where graphene is carried into the cutting zone by jetting or atomizing a carrier fluid. The study involving the embedded delivery method is focused on the micro-machining performance of hierarchical graphene composites. The results of this study show that the presence of graphene in the epoxy matrix improves the machinability of the composite. In general, the tool wear, cutting forces, surface roughness, and extent of delamination are all seen to be lower for the hierarchical composite when compared to the conventional two-phase glass fiber composite. These improvements are attributed to the fact that graphene platelets improve the thermal conductivity of the matrix, provide lubrication at the tool-chip interface and also improve the interface strength between the glass fibers and the matrix. The benefits of graphene are seen to also carry over to the external delivery method. The platelets provide improved cooling and lubrication performance to both environmentally-benign cutting fluids as well as to semi-synthetic cutting fluids used in micro-machining. The cutting performance is seen to be a function of the geometry (i.e., lateral size and thickness) and extent of oxygen-functionalization of the platelet. Ultrasonically exfoliated platelets (with 2--3 graphene layers and lowest in-solution characteristic lateral length of 120 nm) appear to be the most favorable for micro-machining applications. Even at the lowest concentration of 0.1 wt%, they are capable of providing a 51% reduction in the cutting temperature and a 25% reduction in the surface roughness value over that of the baseline semi-synthetic cutting fluid. For the thermally-reduced platelets (with 4--8 graphene layers and in-solution characteristic lateral length of 562--2780 nm), a concentration of 0.2 wt% appears to be optimal. An investigation into the impingement dynamics of the graphene-laden colloidal solutions on a heated substrate reveals that the most important criterion dictating their machining performance is their ability to form uniform, submicron thick films of the platelets upon evaporation of the carrier fluid. As such, the characterization of the residual platelet film left behind on a heated substrate may be an effective technique for evaluating different graphene colloidal solutions for cutting fluids applications in micromachining. Graphene platelets have also recently been shown to reduce the aggressive chemical wear of diamond tools during the machining of transition metal alloys. However, the specific mechanisms responsible for this improvement are currently unknown. The modeling work presented in this thesis uses molecular dynamics techniques to shed light on the wear mitigation mechanisms that are active during the diamond cutting of steel when in the presence of graphene platelets. The dual mechanisms responsible for graphene-induced chemical wear mitigation are: 1) The formation of a physical barrier between the metal and tool atoms, preventing graphitization; and 2) The preferential transfer of carbon from the graphene platelet rather than from the diamond tool. The results of the simulations also provide new insight into the behavior of the 2D graphene platelets in the cutting zone, specifically illustrating the mechanisms of cleaving and interlayer sliding in graphene platelets under the high pressures in cutting zones.

Comparative study of coated and uncoated tool inserts with dry machining of EN47 steel using Taguchi L9 optimization technique

NASA Astrophysics Data System (ADS)

Vasu, M.; Shivananda, Nayaka H.

2018-04-01

EN47 steel samples are machined on a self-centered lathe using Chemical Vapor Deposition of coated TiCN/Al2O3/TiN and uncoated tungsten carbide tool inserts, with nose radius 0.8mm. Results are compared with each other and optimized using statistical tool. Input (cutting) parameters that are considered in this work are feed rate (f), cutting speed (Vc), and depth of cut (ap), the optimization criteria are based on the Taguchi (L9) orthogonal array. ANOVA method is adopted to evaluate the statistical significance and also percentage contribution for each model. Multiple response characteristics namely cutting force (Fz), tool tip temperature (T) and surface roughness (Ra) are evaluated. The results discovered that coated tool insert (TiCN/Al2O3/TiN) exhibits 1.27 and 1.29 times better than the uncoated tool insert for tool tip temperature and surface roughness respectively. A slight increase in cutting force was observed for coated tools.

Condition monitoring of turning process using infrared thermography technique - An experimental approach

NASA Astrophysics Data System (ADS)

Prasad, Balla Srinivasa; Prabha, K. Aruna; Kumar, P. V. S. Ganesh

2017-03-01

In metal cutting machining, major factors that affect the cutting tool life are machine tool vibrations, tool tip/chip temperature and surface roughness along with machining parameters like cutting speed, feed rate, depth of cut, tool geometry, etc., so it becomes important for the manufacturing industry to find the suitable levels of process parameters for obtaining maintaining tool life. Heat generation in cutting was always a main topic to be studied in machining. Recent advancement in signal processing and information technology has resulted in the use of multiple sensors for development of the effective monitoring of tool condition monitoring systems with improved accuracy. From a process improvement point of view, it is definitely more advantageous to proactively monitor quality directly in the process instead of the product, so that the consequences of a defective part can be minimized or even eliminated. In the present work, a real time process monitoring method is explored using multiple sensors. It focuses on the development of a test bed for monitoring the tool condition in turning of AISI 316L steel by using both coated and uncoated carbide inserts. Proposed tool condition monitoring (TCM) is evaluated in the high speed turning using multiple sensors such as Laser Doppler vibrometer and infrared thermography technique. The results indicate the feasibility of using the dominant frequency of the vibration signals for the monitoring of high speed turning operations along with temperatures gradient. A possible correlation is identified in both regular and irregular cutting tool wear. While cutting speed and feed rate proved to be influential parameter on the depicted temperatures and depth of cut to be less influential. Generally, it is observed that lower heat and temperatures are generated when coated inserts are employed. It is found that cutting temperatures are gradually increased as edge wear and deformation developed.

A novel toolpath force prediction algorithm using CAM volumetric data for optimizing robotic arthroplasty.

PubMed

Kianmajd, Babak; Carter, David; Soshi, Masakazu

2016-10-01

Robotic total hip arthroplasty is a procedure in which milling operations are performed on the femur to remove material for the insertion of a prosthetic implant. The robot performs the milling operation by following a sequential list of tool motions, also known as a toolpath, generated by a computer-aided manufacturing (CAM) software. The purpose of this paper is to explain a new toolpath force prediction algorithm that predicts cutting forces, which results in improving the quality and safety of surgical systems. With a custom macro developed in the CAM system's native application programming interface, cutting contact patch volume was extracted from CAM simulations. A time domain cutting force model was then developed through the use of a cutting force prediction algorithm. The second portion validated the algorithm by machining a hip canal in simulated bone using a CNC machine. Average cutting forces were measured during machining using a dynamometer and compared to the values predicted from CAM simulation data using the proposed method. The results showed the predicted forces matched the measured forces in both magnitude and overall pattern shape. However, due to inconsistent motion control, the time duration of the forces was slightly distorted. Nevertheless, the algorithm effectively predicted the forces throughout an entire hip canal procedure. This method provides a fast and easy technique for predicting cutting forces during orthopedic milling by utilizing data within a CAM software.

Root dentine and endodontic instrumentation: cutting edge microscopic imaging

PubMed Central

2016-01-01

Cutting of the dental hard tissues is an integral part of restorative dentistry. Cutting of the root dentine is also needed in preparation prior to endodontic treatment, with significant commercial investment for the development of flexible cutting instruments based around nickel titanium (NiTi) alloys. This paper describes the evolution of endodontic cutting instruments, both in materials used, e.g. the transition from stainless steel to NiTi, and the design of the actual instruments themselves and their method of activation—by hand or motor driven. We have been examining tooth-cutting interactions microscopically for over 25 years using a variety of microscopic techniques; in particular, video-rate confocal microscopy. This has given a unique insight into how many of the procedures that we take for granted are achieved in clinical practice, by showing microscopic video images of the cutting as it occurs within the tooth. This technology has now been extended to allow imaging of the endodontic instrument and the root canal wall for the first time. We are able to image dentine distortion and crack propagation during endodontic filing of the root canal space. We are also able to visualize the often claimed, but seldom seen action of contemporary endodontic instruments. PMID:27274802

Root dentine and endodontic instrumentation: cutting edge microscopic imaging.

PubMed

Atmeh, Amre R; Watson, Timothy F

2016-06-06

Cutting of the dental hard tissues is an integral part of restorative dentistry. Cutting of the root dentine is also needed in preparation prior to endodontic treatment, with significant commercial investment for the development of flexible cutting instruments based around nickel titanium (NiTi) alloys. This paper describes the evolution of endodontic cutting instruments, both in materials used, e.g. the transition from stainless steel to NiTi, and the design of the actual instruments themselves and their method of activation-by hand or motor driven. We have been examining tooth-cutting interactions microscopically for over 25 years using a variety of microscopic techniques; in particular, video-rate confocal microscopy. This has given a unique insight into how many of the procedures that we take for granted are achieved in clinical practice, by showing microscopic video images of the cutting as it occurs within the tooth. This technology has now been extended to allow imaging of the endodontic instrument and the root canal wall for the first time. We are able to image dentine distortion and crack propagation during endodontic filing of the root canal space. We are also able to visualize the often claimed, but seldom seen action of contemporary endodontic instruments.

Reconstruction of the esophagojejunostomy by double stapling method using EEA™ OrVil™ in laparoscopic total gastrectomy and proximal gastrectomy

PubMed Central

2011-01-01

Here we report the method of anastomosis based on double stapling technique (hereinafter, DST) using a trans-oral anvil delivery system (EEATM OrVilTM) for reconstructing the esophagus and lifted jejunum following laparoscopic total gastrectomy or proximal gastric resection. As a basic technique, laparoscopic total gastrectomy employed Roux-en-Y reconstruction, laparoscopic proximal gastrectomy employed double tract reconstruction, and end-to-side anastomosis was used for the cut-off stump of the esophagus and lifted jejunum. We used EEATM OrVilTM as a device that permitted mechanical purse-string suture similarly to conventional EEA, and endo-Surgitie. After the gastric lymph node dissection, the esophagus was cut off using an automated stapler. EEATM OrVilTM was orally and slowly inserted from the valve tip, and a small hole was created at the tip of the obliquely cut-off stump with scissors to let the valve tip pass through. Yarn was cut to disconnect the anvil from a tube and the anvil head was retained in the esophagus. The end-Surgitie was inserted at the right subcostal margin, and after the looped-shaped thread was wrapped around the esophageal stump opening, assisting Maryland forceps inserted at the left subcostal and left abdomen were used to grasp the left and right esophageal stump. The surgeon inserted anvil grasping forceps into the right abdomen, and after grasping the esophagus with the forceps, tightened the end Surgitie, thereby completing the purse-string suture on the esophageal stump. The main unit of the automated stapler was inserted from the cut-off stump of the lifted jejunum, and a trocar was made to pass through. To prevent dropout of the small intestines from the automated stapler, the automated stapler and the lifted jejunum were fastened with silk thread, the abdomen was again inflated, and the lifted jejunum was led into the abdominal cavity. When it was confirmed that the automated stapler and center rod were made completely linear, the anvil and the main unit were connected with each other and firing was carried out. Then, DST-based anastomosis was completed with no dog-ear. The method may facilitate safe laparoscopic anastomosis between the esophagus and reconstructed intestine. This is also considered to serve as a useful anastomosis technique for upper levels of the esophagus in laparotomy. PMID:21599911

Laser cutting: industrial relevance, process optimization, and laser safety

NASA Astrophysics Data System (ADS)

Haferkamp, Heinz; Goede, Martin; von Busse, Alexander; Thuerk, Oliver

1998-09-01

Compared to other technological relevant laser machining processes, up to now laser cutting is the application most frequently used. With respect to the large amount of possible fields of application and the variety of different materials that can be machined, this technology has reached a stable position within the world market of material processing. Reachable machining quality for laser beam cutting is influenced by various laser and process parameters. Process integrated quality techniques have to be applied to ensure high-quality products and a cost effective use of the laser manufacturing plant. Therefore, rugged and versatile online process monitoring techniques at an affordable price would be desirable. Methods for the characterization of single plant components (e.g. laser source and optical path) have to be substituted by an omnivalent control system, capable of process data acquisition and analysis as well as the automatic adaptation of machining and laser parameters to changes in process and ambient conditions. At the Laser Zentrum Hannover eV, locally highly resolved thermographic measurements of the temperature distribution within the processing zone using cost effective measuring devices are performed. Characteristic values for cutting quality and plunge control as well as for the optimization of the surface roughness at the cutting edges can be deducted from the spatial distribution of the temperature field and the measured temperature gradients. Main influencing parameters on the temperature characteristic within the cutting zone are the laser beam intensity and pulse duration in pulse operation mode. For continuous operation mode, the temperature distribution is mainly determined by the laser output power related to the cutting velocity. With higher cutting velocities temperatures at the cutting front increase, reaching their maximum at the optimum cutting velocity. Here absorption of the incident laser radiation is drastically increased due to the angle between the normal of the cutting front and the laser beam axis. Beneath process optimization and control further work is focused on the characterization of particulate and gaseous laser generated air contaminants and adequate safety precautions like exhaust and filter systems.

[The "gentle caesarean section" - an alternative to the classical way of sectio. A prospective comparison between the classical technique and the method of Misgav Ladach].

PubMed

Redlich, A; Köppe, I

2001-11-01

A new technical variant of caesarean section was described a few years ago, which is characterised by blunt surgical preparation and simplified seam technique. A prospective investigation compared the differences in the surgery and postoperative process as well as the rate of complications between this Misgav Ladach method and the conventional technique of Sectio. The individual postoperative well-being of the women was recorded by visual analog scales. - Women, whom realize the including criterias (first caesarean section, >/= 32. week of pregnancy, one baby), were examined in this study over one year: 105 patients operated with the Misgav Ladach method and 67 conventionally operated patients. The patients were randomized in a function of the first letter of the surname (A-K: Misgav-Ladach method; L-Z: classical technique). - The surgical time from the cut to the seam was significantly shorter (29.8 vs. 49.3 min; p < 0,001) in the Misgav Ladach group. There were no differences between the two methods in the rate of postoperative complications. The febrile morbidity was equivalent in both groups (7.6 % vs. 9 %), likewise the frequency of postoperative hematomas (3.8 % vs. 3 %). The postoperative period with consumption of analgetics was significantly longer in the group of conventionally operated patients (1.9 d vs. 2.4 d; p < 0.01). The postoperative presentness was estimated significantly better (p < 0,.01) by the patients of the Misgav ladach group - probably caused by the significantly earlier mobilization (p < 0.05). - The surgical technique described by Misgav and Ladach allows a safe execution of the caesarean section and represents an alternative to the conventional method. The duration of operation (cut-seam-time) was significantly shorter. The technique of less traumatising of tissue caused a significantly earlier mobilisation and a significantly shorter requirement of analgetics. The women estimated her postoperative physical condition as better.

Logging while fishing: An alternate method to cut and thread fishing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tollefsen, E.; Crary, S.; Flores, B.

1996-12-31

New technology has been introduced to allow completion of the wireline logging program after the tool string has become lodged in the wellbore. Charges associated with extracting a stuck tool are substantial. These charges result from the nonproductive time during the fishing trip, an associated wiper trip, and re-logging the well. The ability to continue the logging program while retrieving the logging string from the wellbore is needed. Logging While Fishing (LWF) is a hybrid of existing technologies combined with a new sub capable of severing a cable remotely. This new method is comprised of cut and thread fishing, drillpipemore » conveyed logging, and bridled tool techniques. Utilizing these techniques it is possible to complete wireline logging operations while removing a stuck tool from the wellbore. Completing logging operations using this hybrid method will save operating companies time and money. Other benefits, depending on the situation, include reduced fishing time and an increased level of safety. This application has been demonstrated on jobs in the Gulf of Mexico, North Sea, Venezuela, and Southeast Asia.« less

Wave guide impedance matching method and apparatus

DOEpatents

Kronberg, James W.

1990-01-01

A technique for modifying the end portion of a wave guide, whether hollow or solid, carrying electromagnetic, acoustic or optical energy, to produce a gradual impedance change over the length of the end portion, comprising the cutting of longitudinal, V-shaped grooves that increase in width and depth from beginning of the end portion of the wave guide to the end of the guide so that, at the end of the guide, no guide material remains and no surfaces of the guide as modified are perpendicular to the direction of energy flow. For hollow guides, the grooves are cut beginning on the interior surface; for solid guides, the grooves are cut beginning on the exterior surface. One or more resistive, partially conductive or nonconductive sleeves can be placed over the exterior of the guide and through which the grooves are cut to smooth the transition to free space.

Analysis of the temperature of the hot tool in the cut of woven fabric using infrared images

NASA Astrophysics Data System (ADS)

Borelli, Joao E.; Verderio, Leonardo A.; Gonzaga, Adilson; Ruffino, Rosalvo T.

2001-03-01

Textile manufacture occupies a prominence place in the national economy. By virtue of its importance researches have been made on the development of new materials, equipment and methods used in the production process. The cutting of textiles starts in the basic stage, to be followed within the process of the making of clothes and other articles. In the hot cutting of fabric, one of the variables of great importance in the control of the process is the contact temperature between the tool and the fabric. The work presents a technique for the measurement of the temperature based on the processing of infrared images. For this a system was developed composed of an infrared camera, a framegrabber PC board and software that analyzes the punctual temperature in the cut area enabling the operator to achieve the necessary control of the other variables involved in the process.

Investigation of machinability characteristics on EN47 steel for cutting force and tool wear using optimization technique

NASA Astrophysics Data System (ADS)

M, Vasu; Shivananda Nayaka, H.

2018-06-01

In this experimental work dry turning process carried out on EN47 spring steel with coated tungsten carbide tool insert with 0.8 mm nose radius are optimized by using statistical technique. Experiments were conducted at three different cutting speeds (625, 796 and 1250 rpm) with three different feed rates (0.046, 0.062 and 0.093 mm/rev) and depth of cuts (0.2, 0.3 and 0.4 mm). Experiments are conducted based on full factorial design (FFD) 33 three factors and three levels. Analysis of variance is used to identify significant factor for each output response. The result reveals that feed rate is the most significant factor influencing on cutting force followed by depth of cut and cutting speed having less significance. Optimum machining condition for cutting force obtained from the statistical technique. Tool wear measurements are performed with optimum condition of Vc = 796 rpm, ap = 0.2 mm, f = 0.046 mm/rev. The minimum tool wear observed as 0.086 mm with 5 min machining. Analysis of tool wear was done by confocal microscope it was observed that tool wear increases with increasing cutting time.

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.

Solving Graph Laplacian Systems Through Recursive Bisections and Two-Grid Preconditioning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ponce, Colin; Vassilevski, Panayot S.

2016-02-18

We present a parallelizable direct method for computing the solution to graph Laplacian-based linear systems derived from graphs that can be hierarchically bipartitioned with small edge cuts. For a graph of size n with constant-size edge cuts, our method decomposes a graph Laplacian in time O(n log n), and then uses that decomposition to perform a linear solve in time O(n log n). We then use the developed technique to design a preconditioner for graph Laplacians that do not have this property. Finally, we augment this preconditioner with a two-grid method that accounts for much of the preconditioner's weaknesses. Wemore » present an analysis of this method, as well as a general theorem for the condition number of a general class of two-grid support graph-based preconditioners. Numerical experiments illustrate the performance of the studied methods.« less

Supervoxels for graph cuts-based deformable image registration using guided image filtering

NASA Astrophysics Data System (ADS)

Szmul, Adam; Papież, Bartłomiej W.; Hallack, Andre; Grau, Vicente; Schnabel, Julia A.

2017-11-01

We propose combining a supervoxel-based image representation with the concept of graph cuts as an efficient optimization technique for three-dimensional (3-D) deformable image registration. Due to the pixels/voxels-wise graph construction, the use of graph cuts in this context has been mainly limited to two-dimensional (2-D) applications. However, our work overcomes some of the previous limitations by posing the problem on a graph created by adjacent supervoxels, where the number of nodes in the graph is reduced from the number of voxels to the number of supervoxels. We demonstrate how a supervoxel image representation combined with graph cuts-based optimization can be applied to 3-D data. We further show that the application of a relaxed graph representation of the image, followed by guided image filtering over the estimated deformation field, allows us to model "sliding motion." Applying this method to lung image registration results in highly accurate image registration and anatomically plausible estimations of the deformations. Evaluation of our method on a publicly available computed tomography lung image dataset leads to the observation that our approach compares very favorably with state of the art methods in continuous and discrete image registration, achieving target registration error of 1.16 mm on average per landmark.

Supervoxels for Graph Cuts-Based Deformable Image Registration Using Guided Image Filtering.

PubMed

Szmul, Adam; Papież, Bartłomiej W; Hallack, Andre; Grau, Vicente; Schnabel, Julia A

2017-10-04

In this work we propose to combine a supervoxel-based image representation with the concept of graph cuts as an efficient optimization technique for 3D deformable image registration. Due to the pixels/voxels-wise graph construction, the use of graph cuts in this context has been mainly limited to 2D applications. However, our work overcomes some of the previous limitations by posing the problem on a graph created by adjacent supervoxels, where the number of nodes in the graph is reduced from the number of voxels to the number of supervoxels. We demonstrate how a supervoxel image representation, combined with graph cuts-based optimization can be applied to 3D data. We further show that the application of a relaxed graph representation of the image, followed by guided image filtering over the estimated deformation field, allows us to model 'sliding motion'. Applying this method to lung image registration, results in highly accurate image registration and anatomically plausible estimations of the deformations. Evaluation of our method on a publicly available Computed Tomography lung image dataset (www.dir-lab.com) leads to the observation that our new approach compares very favorably with state-of-the-art in continuous and discrete image registration methods achieving Target Registration Error of 1.16mm on average per landmark.

Supervoxels for Graph Cuts-Based Deformable Image Registration Using Guided Image Filtering

PubMed Central

Szmul, Adam; Papież, Bartłomiej W.; Hallack, Andre; Grau, Vicente; Schnabel, Julia A.

2017-01-01

In this work we propose to combine a supervoxel-based image representation with the concept of graph cuts as an efficient optimization technique for 3D deformable image registration. Due to the pixels/voxels-wise graph construction, the use of graph cuts in this context has been mainly limited to 2D applications. However, our work overcomes some of the previous limitations by posing the problem on a graph created by adjacent supervoxels, where the number of nodes in the graph is reduced from the number of voxels to the number of supervoxels. We demonstrate how a supervoxel image representation, combined with graph cuts-based optimization can be applied to 3D data. We further show that the application of a relaxed graph representation of the image, followed by guided image filtering over the estimated deformation field, allows us to model ‘sliding motion’. Applying this method to lung image registration, results in highly accurate image registration and anatomically plausible estimations of the deformations. Evaluation of our method on a publicly available Computed Tomography lung image dataset (www.dir-lab.com) leads to the observation that our new approach compares very favorably with state-of-the-art in continuous and discrete image registration methods achieving Target Registration Error of 1.16mm on average per landmark. PMID:29225433

Assembly of greek marble inscriptions by isotopic methods.

PubMed

Herz, N; Wenner, D B

1978-03-10

Classical Greek inscriptions cut in marble, whose association as original stelai by archeological methods was debatable, were selected for study. Using traditional geological techniques and determinations of the per mil increments in carbon-13 and oxygen-18, it was determined that fragments could be positively assigned to three stelai, but that fragments from three other stelai had been incorrectly associated.

A field test of cut-off importance sampling for bole volume

Treesearch

Jeffrey H. Gove; Harry T. Valentine; Michael J. Holmes

2000-01-01

Cut-off importance sampling has recently been introduced as a technique for estimating bole volume to some point below the tree tip, termed the cut-off point. A field test of this technique was conducted on a small population of eastern white pine trees using dendrometry as the standard for volume estimation. Results showed that the differences in volume estimates...

Method for Fabricating Composite Structures Including Continuous Press Forming and Pultrusion Processing

NASA Technical Reports Server (NTRS)

Farley, Gary L. (Inventor)

1995-01-01

A method for fabricating composite structures at a low-cost, moderate-to-high production rate is disclosed. A first embodiment of the method includes employing a continuous press forming fabrication process. A second embodiment of the method includes employing a pultrusion process for obtaining composite structures. The methods include coating yarns with matrix material, weaving the yarn into fabric to produce a continuous fabric supply, and feeding multiple layers of net-shaped fabrics having optimally oriented fibers into a debulking tool to form an undebulked preform. The continuous press forming fabrication process includes partially debulking the preform, cutting the partially debulked preform, and debulking the partially debulked preform to form a netshape. An electron-beam or similar technique then cures the structure. The pultrusion fabric process includes feeding the undebulked preform into a heated die and gradually debulking the undebulked preform. The undebulked preform in the heated die changes dimension until a desired cross-sectional dimension is achieved. This process further includes obtaining a net-shaped infiltrated uncured preform, cutting the uncured preform to a desired length, and electron-beam curing (or similar technique) the uncured preform. These fabrication methods produce superior structures formed at higher production rates, resulting in lower cost and high structural performance.

The aggregated unfitted finite element method for elliptic problems

NASA Astrophysics Data System (ADS)

Badia, Santiago; Verdugo, Francesc; Martín, Alberto F.

2018-07-01

Unfitted finite element techniques are valuable tools in different applications where the generation of body-fitted meshes is difficult. However, these techniques are prone to severe ill conditioning problems that obstruct the efficient use of iterative Krylov methods and, in consequence, hinders the practical usage of unfitted methods for realistic large scale applications. In this work, we present a technique that addresses such conditioning problems by constructing enhanced finite element spaces based on a cell aggregation technique. The presented method, called aggregated unfitted finite element method, is easy to implement, and can be used, in contrast to previous works, in Galerkin approximations of coercive problems with conforming Lagrangian finite element spaces. The mathematical analysis of the new method states that the condition number of the resulting linear system matrix scales as in standard finite elements for body-fitted meshes, without being affected by small cut cells, and that the method leads to the optimal finite element convergence order. These theoretical results are confirmed with 2D and 3D numerical experiments.

Accuracy assessment of surgical planning and three-dimensional-printed patient-specific guides for orthopaedic osteotomies.

PubMed

Sys, Gwen; Eykens, Hannelore; Lenaerts, Gerlinde; Shumelinsky, Felix; Robbrecht, Cedric; Poffyn, Bart

2017-06-01

This study analyses the accuracy of three-dimensional pre-operative planning and patient-specific guides for orthopaedic osteotomies. To this end, patient-specific guides were compared to the classical freehand method in an experimental setup with saw bones in two phases. In the first phase, the effect of guide design and oscillating versus reciprocating saws was analysed. The difference between target and performed cuts was quantified by the average distance deviation and average angular deviations in the sagittal and coronal planes for the different osteotomies. The results indicated that for one model osteotomy, the use of guides resulted in a more accurate cut when compared to the freehand technique. Reciprocating saws and slot guides improved accuracy in all planes, while oscillating saws and open guides lead to larger deviations from the planned cut. In the second phase, the accuracy of transfer of the planning to the surgical field with slot guides and a reciprocating saw was assessed and compared to the classical planning and freehand cutting method. The pre-operative plan was transferred with high accuracy. Three-dimensional-printed patient-specific guides improve the accuracy of osteotomies and bony resections in an experimental setup compared to conventional freehand methods. The improved accuracy is related to (1) a detailed and qualitative pre-operative plan and (2) an accurate transfer of the planning to the operation room with patient-specific guides by an accurate guidance of the surgical tools to perform the desired cuts.

Haircutting Guide for Cosmetology Students.

ERIC Educational Resources Information Center

Baker, Linda M.

Intended for use at any point in a beauty culture course, this student manual on haircutting implements and techniques focuses on two basic haircuts--page and short summer cut--to describe and illustrate basic cutting and shaping techniques. There are four major sections in the manual: (1) Hairshaping Implements and Techniques (Implements Used In…

Calcium Isotope Analysis with "Peak Cut" Method on Column Chemistry

NASA Astrophysics Data System (ADS)

Zhu, H.; Zhang, Z.; Liu, F.; Li, X.

2017-12-01

To eliminate isobaric interferences from elemental and molecular isobars (e.g., 40K+, 48Ti+, 88Sr2+, 24Mg16O+, 27Al16O+) on Ca isotopes during mass determination, samples should be purified through ion-exchange column chemistry before analysis. However, large Ca isotopic fractionation has been observed during column chemistry (Russell and Papanastassiou, 1978; Zhu et al., 2016). Therefore, full recovery during column chemistry is greatly needed, otherwise uncertainties would be caused by poor recovery (Zhu et al., 2016). Generally, matrix effects could be enhanced by full recovery, as other elements might overlap with Ca cut during column chemistry. Matrix effects and full recovery are difficult to balance and both need to be considered for high-precision analysis of stable Ca isotopes. Here, we investigate the influence of poor recovery on δ44/40Ca using TIMS with the double spike technique. The δ44/40Ca values of IAPSO seawater, ML3B-G and BHVO-2 in different Ca subcats (e.g., 0-20, 20-40, 40-60, 60-80, 80-100%) with 20% Ca recovery on column chemistry display limited variation after correction by the 42Ca-43Ca double spike technique with the exponential law. Notably, δ44/40Ca of each Ca subcut is quite consistent with δ44/40Ca of Ca cut with full recovery within error. Our results indicate that the 42Ca-43Ca double spike technique can simultaneously correct both of the Ca isotopic fractionation that occurred during column chemistry and thermal ionization mass spectrometry (TIMS) determination properly, because both of the isotopic fractionation occurred during analysis follow the exponential law well. Therefore, we propose the "peak cut" method on Ca column chemistry for samples with complex matrix effects. Briefly, for samples with low Ca contents, we can add the double spike before column chemistry, and only collect the middle of the Ca eluate and abandon the both sides of Ca eluate that might overlap with other elements (e.g., K, Sr). This method would eliminate matrix effects and improve efficiency for the column chemistry.

Optical+NIR Quasar Selection with the SDSS and UKIDSS

NASA Astrophysics Data System (ADS)

Mehta, Sajjan S.; Mahon, R. G.; Richards, G. T.; Hewett, P. C.

2010-01-01

We present the details of an optical+near-IR quasar selection technique, which utilizes near-IR data from the UKIDSS Large Area Survey and the optical data from the Sloan Digital Sky Survey in the SDSS's deep "Stripe 82" region, which covers over 200 deg2. Our selection methods primarily consist of isolating potential candidates in giK and gJK color space, in which there exists a significant separation of the stellar locus from the quasar locus. Additionally, we discuss secondary techniques such as comparison of catalog magnitudes with aperture photometry, analysis of SDSS and UKIDSS morphological type classifications, and flag cuts. Our primary color-cut selections include most quasars with redshifts below 3.4, significantly increasing the completeness both to dust reddened quasars and quasars with redshifts z 2.7 in the SDSS footprint. A simple color cut in the UKIDSS LAS Stripe 82 regions reveals 4200 quasar candidates down to K=18. These NIR selections have been used to contribute to the Baryon Oscillation Spectroscopic Survey (BOSS), which is one of the four surveys of the SDSS-III collaboration. We additionally intend to use our NIR techniques to perform an 8-dimensional optical+NIR Bayesian selection of quasars for the AAOmege UKIDSS SDSS (AUS) survey.

Kinematic differences between optical motion capture and biplanar videoradiography during a jump-cut maneuver

PubMed Central

Miranda, Daniel L; Rainbow, Michael J; Crisco, Joseph J; Fleming, Braden C

2012-01-01

Jumping and cutting activities are investigated in many laboratories attempting to better understand the biomechanics associated with non-contact ACL injury. Optical motion capture is widely used; however, it is subject to soft tissue artifact (STA). Biplanar videoradiography offers a unique approach to collecting skeletal motion without STA. The goal of this study was to compare how STA affects the six-degree-of-freedom motion of the femur and tibia during a jump-cut maneuver associated with non-contact ACL injury. Ten volunteers performed a jump-cut maneuver while their landing leg was imaged using optical motion capture (OMC) and biplanar videoradiography. The within-bone motion differences were compared using anatomical coordinate systems for the femur and tibia, respectively. The knee joint kinematic measurements were compared during two periods: before and after ground contact. Over the entire activity, the within-bone motion differences between the two motion capture techniques were significantly lower for the tibia than the femur for two of the rotational axes (flexion/extension, internal/external) and the origin. The OMC and biplanar videoradiography knee joint kinematics were in best agreement before landing. Kinematic deviations between the two techniques increased significantly after contact. This study provides information on the kinematic discrepancies between OMC and biplanar videoradiography that can be used to optimize methods employing both technologies for studying dynamic in vivo knee kinematics and kinetics during a jump-cut maneuver. PMID:23084785

Performance of Ti-multilayer coated tool during machining of MDN431 alloyed steel

NASA Astrophysics Data System (ADS)

Badiger, Pradeep V.; Desai, Vijay; Ramesh, M. R.

2018-04-01

Turbine forgings and other components are required to be high resistance to corrosion and oxidation because which they are highly alloyed with Ni and Cr. Midhani manufactures one of such material MDN431. It's a hard-to-machine steel with high hardness and strength. PVD coated insert provide an answer to problem with its state of art technique on the WC tool. Machinability studies is carried out on MDN431 steel using uncoated and Ti-multilayer coated WC tool insert using Taguchi optimisation technique. During the present investigation, speed (398-625rpm), feed (0.093-0.175mm/rev), and depth of cut (0.2-0.4mm) varied according to Taguchi L9 orthogonal array, subsequently cutting forces and surface roughness (Ra) were measured. Optimizations of the obtained results are done using Taguchi technique for cutting forces and surface roughness. Using Taguchi technique linear fit model regression analysis carried out for the combination of each input variable. Experimented results are compared and found the developed model is adequate which supported by proof trials. Speed, feed and depth of cut are linearly dependent on the cutting force and surface roughness for uncoated insert whereas Speed and depth of cut feed is inversely dependent in coated insert for both cutting force and surface roughness. Machined surface for coated and uncoated inserts during machining of MDN431 is studied using optical profilometer.

Differences in sampling techniques on total post-mortem tryptase.

PubMed

Tse, R; Garland, J; Kesha, K; Elstub, H; Cala, A D; Ahn, Y; Stables, S; Palmiere, C

2018-05-01

The measurement of mast cell tryptase is commonly used to support the diagnosis of anaphylaxis. In the post-mortem setting, the literature recommends sampling from peripheral blood sources (femoral blood) but does not specify the exact sampling technique. Sampling techniques vary between pathologists, and it is unclear whether different sampling techniques have any impact on post-mortem tryptase levels. The aim of this study is to compare the difference in femoral total post-mortem tryptase levels between two sampling techniques. A 6-month retrospective study comparing femoral total post-mortem tryptase levels between (1) aspirating femoral vessels with a needle and syringe prior to evisceration and (2) femoral vein cut down during evisceration. Twenty cases were identified, with three cases excluded from analysis. There was a statistically significant difference (paired t test, p < 0.05) between mean post-mortem tryptase by aspiration (10.87 ug/L) and by cut down (14.15 ug/L). The mean difference between the two methods was 3.28 ug/L (median, 1.4 ug/L; min, - 6.1 ug/L; max, 16.5 ug/L; 95% CI, 0.001-6.564 ug/L). Femoral total post-mortem tryptase is significantly different, albeit by a small amount, between the two sampling methods. The clinical significance of this finding and what factors may contribute to it are unclear. When requesting post-mortem tryptase, the pathologist should consider documenting the exact blood collection site and method used for collection. In addition, blood samples acquired by different techniques should not be mixed together and should be analyzed separately if possible.

[Prediction of the side-cut product yield of atmospheric/vacuum distillation unit by NIR crude oil rapid assay].

PubMed

Wang, Yan-Bin; Hu, Yu-Zhong; Li, Wen-Le; Zhang, Wei-Song; Zhou, Feng; Luo, Zhi

2014-10-01

In the present paper, based on the fast evaluation technique of near infrared, a method to predict the yield of atmos- pheric and vacuum line was developed, combined with H/CAMS software. Firstly, the near-infrared (NIR) spectroscopy method for rapidly determining the true boiling point of crude oil was developed. With commercially available crude oil spectroscopy da- tabase and experiments test from Guangxi Petrochemical Company, calibration model was established and a topological method was used as the calibration. The model can be employed to predict the true boiling point of crude oil. Secondly, the true boiling point based on NIR rapid assay was converted to the side-cut product yield of atmospheric/vacuum distillation unit by H/CAMS software. The predicted yield and the actual yield of distillation product for naphtha, diesel, wax and residual oil were compared in a 7-month period. The result showed that the NIR rapid crude assay can predict the side-cut product yield accurately. The near infrared analytic method for predicting yield has the advantages of fast analysis, reliable results, and being easy to online operate, and it can provide elementary data for refinery planning optimization and crude oil blending.

A theoretical approach to sound propagation and radiation for ducts with suppressors

NASA Technical Reports Server (NTRS)

Rice, E. J.; Sawdy, D. T.

1981-01-01

The several phenomena involved in theoretical prediction of the far-field sound radiation attenuation from an acoustically lined duct were studied. These include absorption by the suppressor, termination reflections, and far-field radiation. Extensive parametric studies show that the suppressor absorption performance can be correlated with mode cut-off ratio or angle of propagation. The other phenomena can be shown to depend explicitly upon mode cut-off ratio. A complete system can thus be generated which can be used to evaluate aircraft sound suppressors and which can be related to the sound source through the cut-off ratio-acoustic power distribution. Although the method is most fully developed for inlet suppressors, several aft radiated noise phenomena are also discussed. This simplified suppressor design and evaluation method is summarized, the recent improvements in the technique are presented, and areas where further refinement is necessary are discussed. Noise suppressor data from engine experiments are compared with the theoretical calculations.

An Endovascular Strategy for Occlusion or Stenosis with Severe Calcification in the Non-Stenting Zone, creatinG Lumens And SlitS with Crosser in Unique Technique (GLASS CUT): A Case Report.

PubMed

Maruyama, Takashi; Miyamoto, Akira

2017-12-25

In treating non-stenting zones (NSZs), such as the common femoral artery (CFA) and popliteal artery (PA), the best method to treat severely calcified NSZ lesions remains controversial. Here we describe a new method for the treatment of severely calcified PA and CFA lesions using the Crosser® system (CS). After the first wire passed the lesion, the CS was passed through the other wire to create new cracks and lumens (NCAL) in both cases. After creating NCAL around the lumen of the first wire, a large scoring balloon was inflated to crush the severe calcification like a "GLASS CUT" with a glass knife.

Substantivity of hypochlorous acid-based disinfectant against biofilm formation in the dental unit waterlines

PubMed Central

Shajahan, Irfana Fathima; Kandaswamy, Deivanayagam; Lakshminarayanan, L.; Selvarajan, R.

2017-01-01

Objective: The purpose of the study was to examine the substantivity of a new disinfectant against biofilm formation in the dental unit waterlines. Materials and Methods: Twenty dental units were selected for the study and divided into two groups: Group A (dental unit waterlines treated with the disinfectant) and Group B (untreated dental unit waterlines). Biofilm formation was monitored in both groups by removing the one dental unit waterline from each group for the period of 10 days. One inch of the dental unit waterline tube was cut at random site, and the inner lumen of the cut sections was analyzed using the scanning electron microscope (SEM) (TESCAN VEGA3 SBU). Results: On examination, SEM images showed that there was no slime layer or bacterial cells seen in cut section for the period of 7 days in the treated dental waterlines, which means that there is no evident of biofilm formation. In the untreated dental unit waterline cut section, slime layer was observed from day 1. Conclusion: Disinfectant solution was proved to be effective for 7 days against biofilm formation. This technique could be used as a valid method for disinfection of dental unit waterlines. PMID:28761244

Real-time simulation of contact and cutting of heterogeneous soft-tissues.

PubMed

Courtecuisse, Hadrien; Allard, Jérémie; Kerfriden, Pierre; Bordas, Stéphane P A; Cotin, Stéphane; Duriez, Christian

2014-02-01

This paper presents a numerical method for interactive (real-time) simulations, which considerably improves the accuracy of the response of heterogeneous soft-tissue models undergoing contact, cutting and other topological changes. We provide an integrated methodology able to deal both with the ill-conditioning issues associated with material heterogeneities, contact boundary conditions which are one of the main sources of inaccuracies, and cutting which is one of the most challenging issues in interactive simulations. Our approach is based on an implicit time integration of a non-linear finite element model. To enable real-time computations, we propose a new preconditioning technique, based on an asynchronous update at low frequency. The preconditioner is not only used to improve the computation of the deformation of the tissues, but also to simulate the contact response of homogeneous and heterogeneous bodies with the same accuracy. We also address the problem of cutting the heterogeneous structures and propose a method to update the preconditioner according to the topological modifications. Finally, we apply our approach to three challenging demonstrators: (i) a simulation of cataract surgery (ii) a simulation of laparoscopic hepatectomy (iii) a brain tumor surgery. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

Simple to complex modeling of breathing volume using a motion sensor.

PubMed

John, Dinesh; Staudenmayer, John; Freedson, Patty

2013-06-01

To compare simple and complex modeling techniques to estimate categories of low, medium, and high ventilation (VE) from ActiGraph™ activity counts. Vertical axis ActiGraph™ GT1M activity counts, oxygen consumption and VE were measured during treadmill walking and running, sports, household chores and labor-intensive employment activities. Categories of low (<19.3 l/min), medium (19.3 to 35.4 l/min) and high (>35.4 l/min) VEs were derived from activity intensity classifications (light <2.9 METs, moderate 3.0 to 5.9 METs and vigorous >6.0 METs). We examined the accuracy of two simple techniques (multiple regression and activity count cut-point analyses) and one complex (random forest technique) modeling technique in predicting VE from activity counts. Prediction accuracy of the complex random forest technique was marginally better than the simple multiple regression method. Both techniques accurately predicted VE categories almost 80% of the time. The multiple regression and random forest techniques were more accurate (85 to 88%) in predicting medium VE. Both techniques predicted the high VE (70 to 73%) with greater accuracy than low VE (57 to 60%). Actigraph™ cut-points for light, medium and high VEs were <1381, 1381 to 3660 and >3660 cpm. There were minor differences in prediction accuracy between the multiple regression and the random forest technique. This study provides methods to objectively estimate VE categories using activity monitors that can easily be deployed in the field. Objective estimates of VE should provide a better understanding of the dose-response relationship between internal exposure to pollutants and disease. Copyright © 2013 Elsevier B.V. All rights reserved.

Performance Monitoring Of A Computer Numerically Controlled (CNC) Lathe Using Pattern Recognition Techniques

NASA Astrophysics Data System (ADS)

Daneshmend, L. K.; Pak, H. A.

1984-02-01

On-line monitoring of the cutting process in CNC lathe is desirable to ensure unattended fault-free operation in an automated environment. The state of the cutting tool is one of the most important parameters which characterises the cutting process. Direct monitoring of the cutting tool or workpiece is not feasible during machining. However several variables related to the state of the tool can be measured on-line. A novel monitoring technique is presented which uses cutting torque as the variable for on-line monitoring. A classifier is designed on the basis of the empirical relationship between cutting torque and flank wear. The empirical model required by the on-line classifier is established during an automated training cycle using machine vision for off-line direct inspection of the tool.

Reliability and Validity of 10 Different Standard Setting Procedures.

ERIC Educational Resources Information Center

Halpin, Glennelle; Halpin, Gerald

Research indicating that different cut-off points result from the use of different standard-setting techniques leaves decision makers with a disturbing dilemma: Which standard-setting method is best? This investigation of the reliability and validity of 10 different standard-setting approaches was designed to provide information that might help…

Producing gapped-ferrite transformer cores

NASA Technical Reports Server (NTRS)

Mclyman, W. T.

1980-01-01

Improved manufacturing techniques make reproducible gaps and minimize cracking. Molded, unfired transformer cores are cut with thin saw and then fired. Hardened semicircular core sections are bonded together, placed in aluminum core box, and fluidized-coated. After winding is run over box, core is potted. Economical method significantly reduces number of rejects.

Rooting of conifer propagules

Treesearch

R.L. Mott

1977-01-01

An outline of the general problems involved with the propagation of elite conifer clones by rooted cuttings is drawn from published reports. New approaches for resolving these problems can come from studies of clone production through tissue culture methods. Probable extension of tissue culture techniques will permit the establishment of clones from adult, proven trees...

Evolutionary Bi-objective Optimization for Bulldozer and Its Blade in Soil Cutting

NASA Astrophysics Data System (ADS)

Sharma, Deepak; Barakat, Nada

2018-02-01

An evolutionary optimization approach is adopted in this paper for simultaneously achieving the economic and productive soil cutting. The economic aspect is defined by minimizing the power requirement from the bulldozer, and the soil cutting is made productive by minimizing the time of soil cutting. For determining the power requirement, two force models are adopted from the literature to quantify the cutting force on the blade. Three domain-specific constraints are also proposed, which are limiting the power from the bulldozer, limiting the maximum force on the bulldozer blade and achieving the desired production rate. The bi-objective optimization problem is solved using five benchmark multi-objective evolutionary algorithms and one classical optimization technique using the ɛ-constraint method. The Pareto-optimal solutions are obtained with the knee-region. Further, the post-optimal analysis is performed on the obtained solutions to decipher relationships among the objectives and decision variables. Such relationships are later used for making guidelines for selecting the optimal set of input parameters. The obtained results are then compared with the experiment results from the literature that show a close agreement among them.

Assessment of wear dependence parameters in complex model of cutting tool wear

NASA Astrophysics Data System (ADS)

Antsev, A. V.; Pasko, N. I.; Antseva, N. V.

2018-03-01

This paper addresses wear dependence of the generic efficient life period of cutting tools taken as an aggregate of the law of tool wear rate distribution and dependence of parameters of this law's on the cutting mode, factoring in the random factor as exemplified by the complex model of wear. The complex model of wear takes into account the variance of cutting properties within one batch of tools, variance in machinability within one batch of workpieces, and the stochastic nature of the wear process itself. A technique of assessment of wear dependence parameters in a complex model of cutting tool wear is provided. The technique is supported by a numerical example.

Jumbo Cutter for Removal of A Bent Femoral Interlocking Nail: A Cost Effective Method

PubMed Central

Dhanda, Manjeet Singh; Sharma, Sansar C; Ali, Nadeem; Bhat, Abedullah

2015-01-01

Closed diaphyseal femoral shaft fractures can be treated with multiple surgical options. It is more challenging to remove a bent nail than a broken one because it is difficult to retrieve the bent nail through the intramedullary canal. Various authors have published their techniques for removal of bent femoral interlocking nail. This article describes a simple technique using Jumbo cutter for sectioning and removal of bent interlocking nail. This technique will help orthopaedic surgeons to remove bent nail without using any specialised metal cutting instruments. PMID:26266173

Multiresponse Optimization of Process Parameters in Turning of GFRP Using TOPSIS Method

PubMed Central

Parida, Arun Kumar; Routara, Bharat Chandra

2014-01-01

Taguchi's design of experiment is utilized to optimize the process parameters in turning operation with dry environment. Three parameters, cutting speed (v), feed (f), and depth of cut (d), with three different levels are taken for the responses like material removal rate (MRR) and surface roughness (R a). The machining is conducted with Taguchi L9 orthogonal array, and based on the S/N analysis, the optimal process parameters for surface roughness and MRR are calculated separately. Considering the larger-the-better approach, optimal process parameters for material removal rate are cutting speed at level 3, feed at level 2, and depth of cut at level 3, that is, v 3-f 2-d 3. Similarly for surface roughness, considering smaller-the-better approach, the optimal process parameters are cutting speed at level 1, feed at level 1, and depth of cut at level 3, that is, v 1-f 1-d 3. Results of the main effects plot indicate that depth of cut is the most influencing parameter for MRR but cutting speed is the most influencing parameter for surface roughness and feed is found to be the least influencing parameter for both the responses. The confirmation test is conducted for both MRR and surface roughness separately. Finally, an attempt has been made to optimize the multiresponses using technique for order preference by similarity to ideal solution (TOPSIS) with Taguchi approach. PMID:27437503

Film Editing Handbook; Technique of 16mm Film Cutting.

ERIC Educational Resources Information Center

Churchill, Hugh B.

Designed to help the film student with the complexities of 16mm film cutting, this handbook catalogs the mechanical procedures of both picture and sound cutting and supplies step-by-step explanations of these procedures. Because the handbook was organized so that it could be used while working at the cutting bench, common cutting problems and…

Does gang ripping hold the potential for higher clear cutting yields

Treesearch

Hiram Hallock; Pamela Giese

1980-01-01

Cutting yields from gang ripping hardwood lumber graded by the National Hardwood Lumber Association standard grades are determined using the technique of mathematical modeling. The lumber used is the same as that in an earlier mathematically modeled determination of cutting yields from traditional rough mill procedures. Mechanical cutting factors such as kerf, cutting...

Preparation and characterizations of activated carbon monolith from rubber wood and its effect on supercapacitor performances

NASA Astrophysics Data System (ADS)

Taer, E.; Taslim, R.; Deraman, M.

2016-02-01

Preparation of activated carbon monolith (ACM) from rubber wood was investigated. Two kind of preparation method were carried out by pre-carbonized of rubber wood saw dust and rubber wood material as it is naturally. The samples were prepared with pelletizing method and small cutting of rubber wood in cross sectional method. Both of samples were characterized by physical and electrochemical technique. The physical properties such as morphology and porosity were investigated. The electrochemical properties of both samples such as equivalent series resistances (ESR) and specific capacitances were also compared. In conclusion, this study showed that both of different preparation method would propose a simple method of ACM electrode preparation technique for supercapacitor applications.

Technique of laser chromosome welding for chromosome repair and artificial chromosome creation.

PubMed

Huang, Yao-Xiong; Li, Lin; Yang, Liu; Zhang, Yi

2018-04-01

Here we report a technique of laser chromosome welding that uses a violet pulse laser micro-beam for welding. The technique can integrate any size of a desired chromosome fragment into recipient chromosomes by combining with other techniques of laser chromosome manipulation such as chromosome cutting, moving, and stretching. We demonstrated that our method could perform chromosomal modifications with high precision, speed and ease of use in the absence of restriction enzymes, DNA ligases and DNA polymerases. Unlike the conventional methods such as de novo artificial chromosome synthesis, our method has no limitation on the size of the inserted chromosome fragment. The inserted DNA size can be precisely defined and the processed chromosome can retain its intrinsic structure and integrity. Therefore, our technique provides a high quality alternative approach to directed genetic recombination, and can be used for chromosomal repair, removal of defects and artificial chromosome creation. The technique may also have applicability on the manipulation and extension of large pieces of synthetic DNA.

Use of prototype two-channel endoscope with elevator enables larger lift-and-snare endoscopic mucosal resection in a porcine model

PubMed Central

Atkinson, Matthew; Chukwumah, Chike; Marks, Jeffrey; Chak, Amitabh

2014-01-01

Background: Flat and depressed lesions are becoming increasingly recognized in the esophagus, stomach, and colon. Various techniques have been described for endoscopic mucosal resection (EMR) of these lesions. Aims: To evaluate the efficacy of lift-grasp-cut EMR using a prototype dual-channel forward-viewing endoscope with an instrument elevator in one accessory channel (dual-channel elevator scope) as compared to standard dual-channel endoscopes. Methods: EMR was performed using a lift-grasp-cut technique on normal flat rectosigmoid or gastric mucosa in live porcine models after submucosal injection of 4 mL of saline using a dual-channel elevator scope or a standard dual-channel endoscope. With the dual-channel elevator scope, the elevator was used to attain further lifting of the mucosa. The primary endpoint was size of the EMR specimen and the secondary endpoint was number of complications. Results: Twelve experiments were performed (six gastric and six colonic). Mean specimen diameter was 2.27 cm with the dual-channel elevator scope and 1.34 cm with the dual-channel endoscope (P = 0.018). Two colonic perforations occurred with the dual-channel endoscope, vs no complications with the dual-channel elevator scope. Conclusions: The increased lift of the mucosal epithelium, through use of the dual-channel elevator scope, allows for larger EMR when using a lift-grasp-cut technique. Noting the thin nature of the porcine colonic wall, use of the elevator may also make this technique safer. PMID:24760237

The cutting edge - Micro-CT for quantitative toolmark analysis of sharp force trauma to bone.

PubMed

Norman, D G; Watson, D G; Burnett, B; Fenne, P M; Williams, M A

2018-02-01

Toolmark analysis involves examining marks created on an object to identify the likely tool responsible for creating those marks (e.g., a knife). Although a potentially powerful forensic tool, knife mark analysis is still in its infancy and the validation of imaging techniques as well as quantitative approaches is ongoing. This study builds on previous work by simulating real-world stabbings experimentally and statistically exploring quantitative toolmark properties, such as cut mark angle captured by micro-CT imaging, to predict the knife responsible. In Experiment 1 a mechanical stab rig and two knives were used to create 14 knife cut marks on dry pig ribs. The toolmarks were laser and micro-CT scanned to allow for quantitative measurements of numerous toolmark properties. The findings from Experiment 1 demonstrated that both knives produced statistically different cut mark widths, wall angle and shapes. Experiment 2 examined knife marks created on fleshed pig torsos with conditions designed to better simulate real-world stabbings. Eight knives were used to generate 64 incision cut marks that were also micro-CT scanned. Statistical exploration of these cut marks suggested that knife type, serrated or plain, can be predicted from cut mark width and wall angle. Preliminary results suggest that knives type can be predicted from cut mark width, and that knife edge thickness correlates with cut mark width. An additional 16 cut marks walls were imaged for striation marks using scanning electron microscopy with results suggesting that this approach might not be useful for knife mark analysis. Results also indicated that observer judgements of cut mark shape were more consistent when rated from micro-CT images than light microscopy images. The potential to combine micro-CT data, medical grade CT data and photographs to develop highly realistic virtual models for visualisation and 3D printing is also demonstrated. This is the first study to statistically explore simulated real-world knife marks imaged by micro-CT to demonstrate the potential of quantitative approaches in knife mark analysis. Findings and methods presented in this study are relevant to both forensic toolmark researchers as well as practitioners. Limitations of the experimental methodologies and imaging techniques are discussed, and further work is recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

An implicit time-marching method for studying unsteady flow with massive separation

NASA Technical Reports Server (NTRS)

Osswald, G. A.; Ghia, K. N.; Chia, U.

1985-01-01

A fully implicit time-marching method is developed such that all spatial derivatives are approximated using central differences, but no use is made of any artificial dissipation. The numerical method solves the discretized equations using Alternating Direction Implicit-Block Gaussian Elimination technique. The method is implemented in the unsteady analysis, which solves the incompressible Navier-Stokes equations in terms of vorticity and stream function in generalized orthogonal coordinates. A clustered conformal C-grid is employed, and every effort is made to resolve the various length scales in the flow problem. The metric discontinuity at the branch-cut is treated appropriately using analytic continuation. Introduction of the BGE reordering permits implicit treatment of the branch cut in the numerical method. The vorticity singularity at the cusped trailing edge is also appropriately treated. This accurate and efficient implicit method is used to study flow at Re = 1000, past a 12-percent thick symmetric Joukowski airfoil at high angle of attack 30 and 53 deg.

Coatings for minimally processed fruits and vegetables

USDA-ARS?s Scientific Manuscript database

Fresh-cut fruit and vegetables are gaining increasing popularity and market share. Techniques to enhance stability of fresh cut produce are reviewed. Among these techniques, edibles coatings can provide protection against dehydration, microbial decay and decrease events related to physiological sene...

Grading technologies for the manufacture of innovative cutting blades

NASA Astrophysics Data System (ADS)

Rostek, Tim; Homberg, Werner

2018-05-01

Cutting blades for harvesting applications are used in a variety of agricultural machines. These parts are in contact with highly abrasive lawn clippings and often wear out within hours which results in high expensive re-sharpening maintenance. This paper relates to manufacturing techniques enhancing the durability of cutting blades based on a structural analysis of the prevailing wear mechanisms containing chipping and abrasive wear. Each mechanism results in specific demands on the cutting edge's mechanical characteristics. The design of evaluation methods respectively is one issue of the paper. This is basis for approaches to improve the cutting edge performance on purpose. On option to improve abrasive wear resistance and, thus, service life is the application of locally graded steel materials as semi-finished products for self-sharpening cutting blades. These materials comprise a layered structure consisting of a hard, wear resistant layer and a relatively softer layer which is lesser wear resistant. As the cutting blade is subjected to wear conditions, the less wear resistant layer wears faster than the relatively more wear resistant harder layer revealing a durable cross section of the cutting edge and, thus, cutting performance. Anyways, chipping is another key issue on the cutting edge's lifetime. Here, the cutting edges cross section by means of geometry and grind respectively as well as its mechanical properties matter. FEM analysis reveal innovative options to optimize the cross section of the blade as well as thermomechanical strengthening add further strength to reduce chipping. This paper contains a comprehensive strategy to improve cutting blades with use of innovative manufacturing technologies which apply application-specific graded mechanical characteristics and, thus, significantly improved performance characteristics.

Study on electroplating technology of diamond tools for machining hard and brittle materials

NASA Astrophysics Data System (ADS)

Cui, Ying; Chen, Jian Hua; Sun, Li Peng; Wang, Yue

2016-10-01

With the development of the high speed cutting, the ultra-precision machining and ultrasonic vibration technique in processing hard and brittle material , the requirement of cutting tools is becoming higher and higher. As electroplated diamond tools have distinct advantages, such as high adaptability, high durability, long service life and good dimensional stability, the cutting tools are effective and extensive used in grinding hard and brittle materials. In this paper, the coating structure of electroplating diamond tool is described. The electroplating process flow is presented, and the influence of pretreatment on the machining quality is analyzed. Through the experimental research and summary, the reasonable formula of the electrolyte, the electroplating technologic parameters and the suitable sanding method were determined. Meanwhile, the drilling experiment on glass-ceramic shows that the electroplating process can effectively improve the cutting performance of diamond tools. It has laid a good foundation for further improving the quality and efficiency of the machining of hard and brittle materials.

Bacterial rapid identification with matrix assisted laser desorption/ionization time-of-flight mass spectrometry: development of an 'in-house method' and comparison with Bruker Sepsityper(®) kit.

PubMed

Frédéric Ric, S; Antoine, M; Bodson, A; Lissoir, B

2015-10-01

The objective of this study was to compare an in-house matrix-assisted laser desorption ionization with time of flight (MALDI-TOF) method and a commercial MALDI-TOF kit (Sepsityper(®) kit) for direct bacterial identification in positive blood cultures. We also evaluated the time saved and the cost associated with the rapid identification techniques. We used the BACTEC(®) automated system for detecting positive blood cultures. Direct identification using Sepsityper kit and the in-house method were compared with conventional identification by MALDI-TOF using pure bacterial culture on the solid phase. We also evaluated different cut-off scores for rapid bacterial identification. In total, 127 positive blood vials were selected. The rate of rapid identification with the MALDI Sepsityper kit was 25.2% with the standard cut-off and 33.9% with the enlarged cut-off, while the results for the in-house method were 44.1 and 61.4%, respectively. Error rates with the enlarged cut-off were 6.98 (n = 3) and 2.56% (n = 2) for Sepsityper and the in-house method, respectively. Identification rates were higher for gram-negative bacteria. Direct bacterial identification succeeded in supplying rapid identification of the causative organism in cases of sepsis. The time taken to obtain a result was nearly 24  hours shorter for the direct bacterial identification methods than for conventional MALDI-TOF on solid phase culture. Compared with the Sepsityper kit, the in-house method offered better results and fewer errors, was more cost-effective and easier to use.

Study of mandible reconstruction using a fibula flap with application of additive manufacturing technology.

PubMed

Tsai, Ming-June; Wu, Ching-Tsai

2014-05-06

This study aimed to establish surgical guiding techniques for completing mandible lesion resection and reconstruction of the mandible defect area with fibula sections in one surgery by applying additive manufacturing technology, which can reduce the surgical duration and enhance the surgical accuracy and success rate. A computer assisted mandible reconstruction planning (CAMRP) program was used to calculate the optimal cutting length and number of fibula pieces and design the fixtures for mandible cutting, registration, and arrangement of the fibula segments. The mandible cutting and registering fixtures were then generated using an additive manufacturing system. The CAMRP calculated the optimal fibula cutting length and number of segments based on the location and length of the defective portion of the mandible. The mandible cutting jig was generated according to the boundary surface of the lesion resection on the mandible STL model. The fibular cutting fixture was based on the length of each segment, and the registered fixture was used to quickly arrange the fibula pieces into the shape of the defect area. In this study, the mandibular lesion was reconstructed using registered fibular sections in one step, and the method is very easy to perform. The application of additive manufacturing technology provided customized models and the cutting fixtures and registered fixtures, which can improve the efficiency of clinical application. This study showed that the cutting fixture helped to rapidly complete lesion resection and fibula cutting, and the registered fixture enabled arrangement of the fibula pieces and allowed completion of the mandible reconstruction in a timely manner. Our method can overcome the disadvantages of traditional surgery, which requires a long and different course of treatment and is liable to cause error. With the help of optimal cutting planning by the CAMRP and the 3D printed mandible resection jig and fibula cutting fixture, this all-in-one process of mandible reconstruction furnishes many benefits in this field by enhancing the accuracy of surgery, shortening the operation duration, reducing the surgical risk, and resulting in a better mandible appearance of the patients after surgery.

Hydrogen peroxide test for intraoperative bile leak detection.

PubMed

Trehan, V; Rao, Pankaj P; Naidu, C S; Sharma, Anuj K; Singh, A K; Sharma, Sanjay; Gaur, Amit; Kulkarni, S V; Pathak, N

2017-07-01

Bile leakage (BL) is a common complication following liver surgery, ranging from 3 to 27% in different series. To reduce the incidence of post-operative BL various BL tests have been applied since ages, but no method is foolproof and every method has their own limitations. In this study we used a relatively simpler technique to detect the BL intra-operatively. Topical application of 1.5% diluted hydrogen peroxide (H 2 O 2 ) was used to detect the BL from cut surface of liver and we compared this with conventional saline method to know the efficacy. A total of 31 patients included all patients who underwent liver resection and donor hepatectomies as part of Living Donor Liver Transplantation. After complete liver resection, the conventional saline test followed by topical diluted 1.5% H 2 O 2 test was performed on all. A BL was demonstrated in 11 patients (35.48%) by the conventional saline method and in 19 patients (61.29%) by H 2 O 2 method. Statistically compared by Wilcoxon signed-rank test showed significant difference ( P  = 0.014) for minor liver resections group and ( P  = 0.002) for major liver resections group. The topical application of H 2 O 2 is a simple and effective method of detection of BL from cut surface of liver. It is an easy, non-invasive, cheap, less time consuming, reproducible, and sensitive technique with no obvious disadvantages.

Research on subsurface defects of potassium dihydrogen phosphate crystals fabricated by single point diamond turning technique

NASA Astrophysics Data System (ADS)

Tie, Guipeng; Dai, Yifan; Guan, Chaoliang; Chen, Shaoshan; Song, Bing

2013-03-01

Potassium dihydrogen phosphate (KDP) crystals, which are widely used in high-power laser systems, are required to be free of defects on fabricated subsurfaces. The depth of subsurface defects (SSD) of KDP crystals is significantly influenced by the parameters used in the single point diamond turning technique. In this paper, based on the deliquescent magnetorheological finishing technique, the SSD of KDP crystals is observed and the depths under various cutting parameters are detected and discussed. The results indicate that no SSD is generated under small parameters and with the increase of cutting parameters, SSD appears and the depth rises almost linearly. Although the ascending trends of SSD depths caused by cutting depth and feed rate are much alike, the two parameters make different contributions. Taking the same material removal efficiency as a criterion, a large cutting depth generates shallower SSD depth than a large feed rate. Based on the experiment results, an optimized cutting procedure is obtained to generate defect-free surfaces.

Approximation methods for stochastic petri nets

NASA Technical Reports Server (NTRS)

Jungnitz, Hauke Joerg

1992-01-01

Stochastic Marked Graphs are a concurrent decision free formalism provided with a powerful synchronization mechanism generalizing conventional Fork Join Queueing Networks. In some particular cases the analysis of the throughput can be done analytically. Otherwise the analysis suffers from the classical state explosion problem. Embedded in the divide and conquer paradigm, approximation techniques are introduced for the analysis of stochastic marked graphs and Macroplace/Macrotransition-nets (MPMT-nets), a new subclass introduced herein. MPMT-nets are a subclass of Petri nets that allow limited choice, concurrency and sharing of resources. The modeling power of MPMT is much larger than that of marked graphs, e.g., MPMT-nets can model manufacturing flow lines with unreliable machines and dataflow graphs where choice and synchronization occur. The basic idea leads to the notion of a cut to split the original net system into two subnets. The cuts lead to two aggregated net systems where one of the subnets is reduced to a single transition. A further reduction leads to a basic skeleton. The generalization of the idea leads to multiple cuts, where single cuts can be applied recursively leading to a hierarchical decomposition. Based on the decomposition, a response time approximation technique for the performance analysis is introduced. Also, delay equivalence, which has previously been introduced in the context of marked graphs by Woodside et al., Marie's method and flow equivalent aggregation are applied to the aggregated net systems. The experimental results show that response time approximation converges quickly and shows reasonable accuracy in most cases. The convergence of Marie's method and flow equivalent aggregation are applied to the aggregated net systems. The experimental results show that response time approximation converges quickly and shows reasonable accuracy in most cases. The convergence of Marie's is slower, but the accuracy is generally better. Delay equivalence often fails to converge, while flow equivalent aggregation can lead to potentially bad results if a strong dependence of the mean completion time on the interarrival process exists.

Competing Strategies to Balance the Budgets of Publicly Funded Higher Education Institutions

ERIC Educational Resources Information Center

Askari, Mahmoud Yousef

2017-01-01

This paper compares and contrasts different strategies to balance academic institutions' operating budgets. Some strategies use economic theory to recommend a budgeting technique, others use management methods to cut cost, and some strategies use a management accounting approach to reach a balanced budget. Through the use of a simplified numerical…

Lung tumor segmentation in PET images using graph cuts.

PubMed

Ballangan, Cherry; Wang, Xiuying; Fulham, Michael; Eberl, Stefan; Feng, David Dagan

2013-03-01

The aim of segmentation of tumor regions in positron emission tomography (PET) is to provide more accurate measurements of tumor size and extension into adjacent structures, than is possible with visual assessment alone and hence improve patient management decisions. We propose a segmentation energy function for the graph cuts technique to improve lung tumor segmentation with PET. Our segmentation energy is based on an analysis of the tumor voxels in PET images combined with a standardized uptake value (SUV) cost function and a monotonic downhill SUV feature. The monotonic downhill feature avoids segmentation leakage into surrounding tissues with similar or higher PET tracer uptake than the tumor and the SUV cost function improves the boundary definition and also addresses situations where the lung tumor is heterogeneous. We evaluated the method in 42 clinical PET volumes from patients with non-small cell lung cancer (NSCLC). Our method improves segmentation and performs better than region growing approaches, the watershed technique, fuzzy-c-means, region-based active contour and tumor customized downhill. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Surface characteristics and damage distributions of diamond wire sawn wafers for silicon solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sopori, Bhushan; Devayajanam, Srinivas; Basnyat, Prakash

2016-01-01

This paper describes surface characteristics, in terms of its morphology, roughness and near-surface damage of Si wafers cut by diamond wire sawing (DWS) of Si ingots under different cutting conditions. Diamond wire sawn Si wafers exhibit nearly-periodic surface features of different spatial wavelengths, which correspond to kinematics of various movements during wafering, such as ingot feed, wire reciprocation, and wire snap. The surface damage occurs in the form of frozen-in dislocations, phase changes, and microcracks. The in-depth damage was determined by conventional methods such as TEM, SEM and angle-polishing/defect-etching. However, because these methods only provide local information, we have alsomore » applied a new technique that determines average damage depth over a large area. This technique uses sequential measurement of the minority carrier lifetime after etching thin layers from the surfaces. The lateral spatial damage variations, which seem to be mainly related to wire reciprocation process, were observed by photoluminescence and minority carrier lifetime mapping. Our results show a strong correlation of damage depth on the diamond grit size and wire usage.« less

Evolution of treatment of fistula in ano.

PubMed

Blumetti, J; Abcarian, A; Quinteros, F; Chaudhry, V; Prasad, L; Abcarian, H

2012-05-01

Fistula-in-ano is a common medical problem affecting thousands of patients annually. In the past, the options for treatment of fistula-in-ano were limited to fistulotomy and/or seton placement. Current treatment options also include muscle-sparing techniques such as a dermal island flap, endorectal advancement flap, fibrin sealent injection, anal fistula plug, and most recently ligation of the intersphincteric fistula tract (procedure). This study seeks to evaluate types and time trends for treatment of fistula-in-ano. A retrospective review from 1975 to 2009 was performed. Data were collected and sorted into 5-year increments for type and time trends of treatment. Fistulotomy and partial fistulotomy were grouped as cutting procedures. Seton placement, fibrin sealant, dermal flap, endorectal flap, and fistula plug were grouped as noncutting procedures. Statistical analysis was performed for each time period to determine trends. With institutional review board approval, the records of 2,267 fistula operations available for analysis were included. Most of the patients were men (74 vs. 26%). Cutting procedures comprised 66.6% (n = 1510) of all procedures. Noncutting procedures were utilized in 33.4% (n = 757), including Seton placement alone 370 (16.3%), fibrin sealant 168 (7.4%), dermal or endorectal flap 147 (6.5%), and fistula plug 72 (3.2%). The distribution of operations grouped in 5-year intervals is as follows: 1975-1979, 78 cutting and one noncutting; 1980-1984, 170 cutting and 10 noncutting; 1985-1989, 54 cutting and five noncutting; 1990-1994, 37 cutting and six noncutting; 1995-1999, 367 cutting and 167 noncutting; 2000-2004, 514 cutting and 283 noncutting; 2005-2009, 290 cutting and 285 noncutting. The percentage of cutting and noncutting procedures significantly differed over time, with cutting procedures decreasing and noncutting procedures increasing proportionally (χ(2) linear-by-linear association, p < 0.05). Fistula-in-ano remains a common complex disease process. Its treatment has evolved to include a variety of noncutting techniques in addition to traditional fistulotomy. With the advent of more sphincter-sparing techniques, the number of patients undergoing fistulotomy should continue to decrease over time. Surgeons should become familiar with various surgical techniques so the treatment can be tailored to the patient.

Applications of optical sensing for laser cutting and drilling.

PubMed

Fox, Mahlen D T; French, Paul; Peters, Chris; Hand, Duncan P; Jones, Julian D C

2002-08-20

Any reliable automated production system must include process control and monitoring techniques. Two laser processing techniques potentially lending themselves to automation are percussion drilling and cutting. For drilling we investigate the performance of a modification of a nonintrusive optical focus control system we previously developed for laser welding, which exploits the chromatic aberrations of the processing optics to determine focal error. We further developed this focus control system for closed-loop control of laser cutting. We show that an extension of the technique can detect deterioration in cut quality, and we describe practical trials carried out on different materials using both oxygen and nitrogen assist gas. We base our techniques on monitoring the light generated by the process, captured nonintrusively by the effector optics and processed remotely from the workpiece. We describe the relationship between the temporal and the chromatic modulation of the detected light and process quality and show how the information can be used as the basis of a process control system.

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.

Design and Performance of Property Gradient Ternary Nitride Coating Based on Process Control.

PubMed

Yan, Pei; Chen, Kaijie; Wang, Yubin; Zhou, Han; Peng, Zeyu; Jiao, Li; Wang, Xibin

2018-05-09

Surface coating is an effective approach to improve cutting tool performance, and multiple or gradient coating structures have become a common development strategy. However, composition mutations at the interfaces decrease the performance of multi-layered coatings. The key mitigation technique has been to reduce the interface effect at the boundaries. This study proposes a structure design method for property-component gradient coatings based on process control. The method produces coatings with high internal cohesion and high external hardness, which could reduce the composition and performance mutations at the interface. A ZrTiN property gradient ternary nitride coating was deposited on cemented carbide by multi-arc ion plating with separated Ti and Zr targets. The mechanical properties, friction behaviors, and cutting performances were systematically investigated, compared with a single-layer coating. The results indicated that the gradient coating had better friction and wear performance with lower wear rate and higher resistance to peeling off during sliding friction. The gradient coating had better wear and damage resistance in cutting processes, with lower machined surface roughness Ra. Gradient-structured coatings could effectively inhibit micro crack initiation and growth under alternating force and temperature load. This method could be extended to similar ternary nitride coatings.

Welding And Cutting A Nickel Alloy By Laser

NASA Technical Reports Server (NTRS)

Banas, C. M.

1990-01-01

Technique effective and energy-efficient. Report describes evaluation of laser welding and cutting of Inconel(R) 718. Notes that electron-beam welding processes developed for In-718, but difficult to use on large or complex structures. Cutting of In-718 by laser fast and produces only narrow kerf. Cut edge requires dressing, to endure fatigue.

Selection of the most influential factors on the water-jet assisted underwater laser process by adaptive neuro-fuzzy technique

NASA Astrophysics Data System (ADS)

Nikolić, Vlastimir; Petković, Dalibor; Lazov, Lyubomir; Milovančević, Miloš

2016-07-01

Water-jet assisted underwater laser cutting has shown some advantages as it produces much less turbulence, gas bubble and aerosols, resulting in a more gentle process. However, this process has relatively low efficiency due to different losses in water. It is important to determine which parameters are the most important for the process. In this investigation was analyzed the water-jet assisted underwater laser cutting parameters forecasting based on the different parameters. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data in order to select the most influential factors for water-jet assisted underwater laser cutting parameters forecasting. Three inputs are considered: laser power, cutting speed and water-jet speed. The ANFIS process for variable selection was also implemented in order to detect the predominant factors affecting the forecasting of the water-jet assisted underwater laser cutting parameters. According to the results the combination of laser power cutting speed forms the most influential combination foe the prediction of water-jet assisted underwater laser cutting parameters. The best prediction was observed for the bottom kerf-width (R2 = 0.9653). The worst prediction was observed for dross area per unit length (R2 = 0.6804). According to the results, a greater improvement in estimation accuracy can be achieved by removing the unnecessary parameter.

Ceramic tools insert assesment based on vickers indentation methodology

NASA Astrophysics Data System (ADS)

Husni; Rizal, Muhammad; Aziz M, M.; Wahyu, M.

2018-05-01

In the interrupted cutting process, the risk of tool chipping or fracture is higher than continues cutting. Therefore, the selection of suitable ceramic tools for interrupted cutting application become an important issue to assure that the cutting process is running effectively. At present, the performance of ceramics tools is assessed by conducting some cutting tests, which is required time and cost consuming. In this study, the performance of ceramic tools evaluated using hardness tester machine. The technique, in general, has a certain advantage compare with the more conventional methods; the experimental is straightforward involving minimal specimen preparation and the amount of material needed is small. Three types of ceramic tools AS10, CC650 and K090 have been used, each tool was polished then Vickers indentation test were performed with the load were 0.2, 0.5, 1, 2.5, 5 and 10 kgf. The results revealed that among the load used in the tests, the indentation loads of 5 kgf always produce well cracks as compared with others. Among the cutting tool used in the tests, AS10 has produced the shortest crack length and follow by CC 670, and K090. It is indicated that the shortest crack length of AS10 reflected that the tool has a highest dynamic load resistance among others insert.

The critical wave speed for the Fisher Kolmogorov Petrowskii Piscounov equation with cut-off

NASA Astrophysics Data System (ADS)

Dumortier, Freddy; Popovic, Nikola; Kaper, Tasso J.

2007-04-01

The Fisher-Kolmogorov-Petrowskii-Piscounov (FKPP) equation with cut-off was introduced in (Brunet and Derrida 1997 Shift in the velocity of a front due to a cut-off Phys. Rev. E 56 2597-604) to model N-particle systems in which concentrations less than ɛ = 1/N are not attainable. It was conjectured that the cut-off function, which sets the reaction terms to zero if the concentration is below the small threshold ɛ, introduces a substantial shift in the propagation speed of the corresponding travelling waves. In this paper, we prove the conjecture of Brunet and Derrida, showing that the speed of propagation is given by c_crit(\\varepsilon)=2-{\\pi^2}/{(\\ln\\varepsilon)^2}+\\cal{O}((\\ln\\varepsilon)^{-3}) , as ɛ → 0, for a large class of cut-off functions. Moreover, we extend this result to a more general family of scalar reaction-diffusion equations with cut-off. The main mathematical techniques used in our proof are the geometric singular perturbation theory and the blow-up method, which lead naturally to the identification of the reasons for the logarithmic dependence of ccrit on ɛ as well as for the universality of the corresponding leading-order coefficient (π2).

Recycling stabilised/solidified drill cuttings for forage production in acidic soils.

PubMed

Kogbara, Reginald B; Dumkhana, Bernard B; Ayotamuno, Josiah M; Okparanma, Reuben N

2017-10-01

Stabilisation/solidification (S/S), which involves fixation and immobilisation of contaminants using cementitious materials, is one method of treating drill cuttings before final fate. This work considers reuse of stabilised/solidified drill cuttings for forage production in acidic soils. It sought to improve the sustainability of S/S technique through supplementation with the phytoremediation potential of plants, eliminate the need for landfill disposal and reduce soil acidity for better plant growth. Drill cuttings with an initial total petroleum hydrocarbon (TPH) concentration of 17,125 mg kg -1 and low concentrations of metals were treated with 5%, 10%, and 20% cement dosages. The treated drill cuttings were reused in granular form for growing a forage, elephant grass (Pennisetum purpureum), after mixing with uncontaminated soil. The grasses were also grown in uncontaminated soil. The phytoremediation and growth potential of the plants was assessed over a 12-week period. A mix ratio of one part drill cuttings to three parts uncontaminated soil was required for active plant growth. The phytoremediation ability of elephant grass (alongside abiotic losses) reduced the TPH level (up to 8795 mg kg -1 ) in the soil-treated-drill cuttings mixtures below regulatory (1000 mg kg -1 ) levels. There were also decreased concentrations of metals. The grass showed better heights and leaf lengths in soil containing drill cuttings treated with 5% cement dosage than in uncontaminated soil. The results suggest that recycling S/S treated drill cuttings for forage production may be a potential end use of the treated waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

The influence of cutting-bill requirements on lumber yield using a fractional-factorial design part II, correlation and number of part sizes

Treesearch

Urs Buehlmann; D. Earl Kline; Janice K. Wiedenbeck; R., Jr. Noble

2008-01-01

Cutting-bill requirements, among other factors, influence the yield obtained when cutting lumber into parts. The first part of this 2-part series described how different cutting-bill part sizes, when added to an existing cutting-bill, affect lumber yield, and quantified these observations. To accomplish this, the study employed linear least squares estimation technique...

Study of process of trueing diamond grinding wheels on metal bonds by method of free abrasive after processing of leucosapphire blanks

NASA Astrophysics Data System (ADS)

Fedonin, O. N.; Handozhko, A. V.; Fedukov, A. G.

2018-03-01

The problem of mechanical processing, in particular, grinding products from leucosapphire, is considered. The main problem with this treatment is the need to adjust the diamond tool. One of the methods of tool trueing using loose abrasive technique is considered. The results of a study on restoring the tool cutting ability, its shape and profile after straightening are given.

A rapid technique for the histological examination of large ovarian follicles.

PubMed

Driancourt, M A; Mariana, J C; Palmer, E

1981-01-01

A rapid technique for counting and classifying large ovarian follicles of domestic animals is described. Using a cryostat, 250-micrograms thick sections were cut from the frozen ovary; an image of the surface of each ovarian section was recorded on videotape. By replaying the videotape, the largest profile of each follicle larger than 1 mm in diameter was readily identified and measured. The presence or absence of atresia was determined by applying standard histological methods to fragments of individual follicles taken from the frozen sections. The results obtained are similar to those found using previous methods and demand only one-quarter of the time.

Geometrical quality evaluation in laser cutting of Inconel-718 sheet by using Taguchi based regression analysis and particle swarm optimization

NASA Astrophysics Data System (ADS)

Shrivastava, Prashant Kumar; Pandey, Arun Kumar

2018-03-01

The Inconel-718 is one of the most demanding advanced engineering materials because of its superior quality. The conventional machining techniques are facing many problems to cut intricate profiles on these materials due to its minimum thermal conductivity, minimum elastic property and maximum chemical affinity at magnified temperature. The laser beam cutting is one of the advanced cutting method that may be used to achieve the geometrical accuracy with more precision by the suitable management of input process parameters. In this research work, the experimental investigation during the pulsed Nd:YAG laser cutting of Inconel-718 has been carried out. The experiments have been conducted by using the well planned orthogonal array L27. The experimentally measured values of different quality characteristics have been used for developing the second order regression models of bottom kerf deviation (KD), bottom kerf width (KW) and kerf taper (KT). The developed models of different quality characteristics have been utilized as a quality function for single-objective optimization by using particle swarm optimization (PSO) method. The optimum results obtained by the proposed hybrid methodology have been compared with experimental results. The comparison of optimized results with the experimental results shows that an individual improvement of 75%, 12.67% and 33.70% in bottom kerf deviation, bottom kerf width, and kerf taper has been observed. The parametric effects of different most significant input process parameters on quality characteristics have also been discussed.

Comparison of three 15N methods to correct for microbial contamination when assessing in situ protein degradability of fresh forages.

PubMed

Kamoun, M; Ammar, H; Théwis, A; Beckers, Y; France, J; López, S

2014-11-01

The use of stable (15)N as a marker to determine microbial contamination in nylon bag incubation residues to estimate protein degradability was investigated. Three methods using (15)N were compared: (15)N-labeled forage (dilution method, LF), (15)N enrichment of rumen solids-associated bacteria (SAB), and (15)N enrichment of rumen liquid-associated bacteria (LAB). Herbage from forages differing in protein and fiber contents (early-cut Italian ryegrass, late-cut Italian ryegrass, and red clover) were freeze-dried and ground and then incubated in situ in the rumen of 3 steers for 3, 6, 12, 24, and 48 h using the nylon bag technique. The (15)N-labeled forages were obtained by fertilizing the plots where herbage was grown with (15)NH4 (15)NO3. Unlabeled forages (obtained from plots fertilized with NH4NO3) were incubated at the same time that ((15)NH4)2SO4 was continuously infused into the rumen of the steers, and then pellets of labeled SAB and LAB were isolated by differential centrifugation of samples of ruminal contents. The proportion of bacterial N in the incubation residues increased from 0.09 and 0.45 g bacterial N/g total N at 3 h of incubation to 0.37 and 0.85 g bacterial N/g total N at 48 h of incubation for early-cut and late-cut ryegrass, respectively. There were differences (P < 0.001) between uncorrected N degradability values and those corrected for microbial contamination with all of the methods. Apparent N degradability of the low-N, high-fiber forage (late-cut ryegrass) was 0.51, whereas the corrected values were 0.85, 0.84, and 0.77 for the LF, SAB, and LAB methods, respectively. With early-cut ryegrass and red clover, the differences between uncorrected and corrected values ranged between 6% and 13%, with small differences among the labeling methods. Generally, methods using labeled forage or labeled SAB and LAB provided similar corrected degradability values. The accuracy in estimating the extent of degradation of protein in the rumen from in situ disappearance curves is improved when values are corrected for microbial contamination of the bag residue.

Model-based chatter stability prediction and detection for the turning of a flexible workpiece

NASA Astrophysics Data System (ADS)

Lu, Kaibo; Lian, Zisheng; Gu, Fengshou; Liu, Hunju

2018-02-01

Machining long slender workpieces still presents a technical challenge on the shop floor due to their low stiffness and damping. Regenerative chatter is a major hindrance in machining processes, reducing the geometric accuracies and dynamic stability of the cutting system. This study has been motivated by the fact that chatter occurrence is generally in relation to the cutting position in straight turning of slender workpieces, which has seldom been investigated comprehensively in literature. In the present paper, a predictive chatter model of turning a tailstock supported slender workpiece considering the cutting position change during machining is explored. Based on linear stability analysis and stiffness distribution at different cutting positions along the workpiece, the effect of the cutting tool movement along the length of the workpiece on chatter stability is studied. As a result, an entire stability chart for a single cutting pass is constructed. Through this stability chart the critical cutting condition and the chatter onset location along the workpiece in a turning operation can be estimated. The difference between the predicted tool locations and the experimental results was within 9% at high speed cutting. Also, on the basis of the predictive model the dynamic behavior during chatter that when chatter arises at some cutting location it will continue for a period of time until another specified location is arrived at, can be inferred. The experimental observation is in good agreement with the theoretical inference. In chatter detection respect, besides the delay strategy and overlap processing technique, a relative threshold algorithm is proposed to detect chatter by comparing the spectrum and variance of the acquired acceleration signals with the reference saved during stable cutting. The chatter monitoring method has shown reliability for various machining conditions.

Augmentation of the Nasal Dorsum Using the Multistrip Autologous Cartilage Technique.

PubMed

Liu, Liqiang; Bu, Zhaoyun; Fan, Jincai; Tian, Jia; Gan, Cheng; Yang, Zengjie; Jiao, Hu

2017-12-01

Nasal augmentation is a popular modern technique requested by many Asian people. There are two kinds of autologous cartilage used to augment the nose at present: carved as a monobloc or diced into pieces. Each approach has its pros and cons. The authors performed their surgical technique on a group of 28 patients. Twenty of these patients had undergone rhinoplasties performed before referral to our hospital; eight of these patients had undergone a primary rhinoplasty. Bilateral conchal, nasal septum, or rib cartilage was harvested; deep temporal fascia or abdominal muscle fascia to be prepared for packing stripped cartilage was also removed at this time. The cartilage was placed on a plastic cutting board and cut into strips with a transverse section of 1 × 1 mm. Then, these strips were packed and covered by fascia to form the grafts. The median follow-up was 23 months (range, 12 to 48 months). Twenty-two patients were satisfied with their augmented noses. Through examinations, biopsies, and magnetic resonance imaging scans, less resorption was observed with the multistrip autologous cartilage technique. Junctional stepoffs, excessive prominence, and slanting grafts occurred in three patients, two of whom had revisions. Using multistrip autologous cartilage grafts is an easier method to perform and could be another alternative technique for augmentative and reconstructive rhinoplasties.

LOCAL ORTHOGONAL CUTTING METHOD FOR COMPUTING MEDIAL CURVES AND ITS BIOMEDICAL APPLICATIONS

PubMed Central

Einstein, Daniel R.; Dyedov, Vladimir

2010-01-01

Medial curves have a wide range of applications in geometric modeling and analysis (such as shape matching) and biomedical engineering (such as morphometry and computer assisted surgery). The computation of medial curves poses significant challenges, both in terms of theoretical analysis and practical efficiency and reliability. In this paper, we propose a definition and analysis of medial curves and also describe an efficient and robust method called local orthogonal cutting (LOC) for computing medial curves. Our approach is based on three key concepts: a local orthogonal decomposition of objects into substructures, a differential geometry concept called the interior center of curvature (ICC), and integrated stability and consistency tests. These concepts lend themselves to robust numerical techniques and result in an algorithm that is efficient and noise resistant. We illustrate the effectiveness and robustness of our approach with some highly complex, large-scale, noisy biomedical geometries derived from medical images, including lung airways and blood vessels. We also present comparisons of our method with some existing methods. PMID:20628546

Applying Laser Cutting Techniques through Horology for Teaching Effective STEM in Design and Technology

ERIC Educational Resources Information Center

Jones, Lewis C. R.; Tyrer, John R.; Zanker, Nigel P.

2013-01-01

This paper explores the pedagogy underpinning the use of laser manufacturing methods for the teaching of science, technology, engineering and mathematics (STEM) at key stage 3 design and technology. Clock making (horology) has been a popular project in design and technology (D&T) found in many schools, typically it focuses on aesthetical…

Combining Silviculture and Landscape Architecture to Enhance the Roadside View

Treesearch

Philip M. McDonald; R. Burton Litton Jr.

1998-01-01

On a high-quality site in the mixed conifer forest of northern California, understory and overstory vegetation along a 3-mile paved county road were manipulated to enhance the view for the traveler. Traditional silvicultural cutting methods and landscape architectural techniques were blended to give contrast and variability to the vegetation along both sides of the...

Accurate airway segmentation based on intensity structure analysis and graph-cut

NASA Astrophysics Data System (ADS)

Meng, Qier; Kitsaka, Takayuki; Nimura, Yukitaka; Oda, Masahiro; Mori, Kensaku

2016-03-01

This paper presents a novel airway segmentation method based on intensity structure analysis and graph-cut. Airway segmentation is an important step in analyzing chest CT volumes for computerized lung cancer detection, emphysema diagnosis, asthma diagnosis, and pre- and intra-operative bronchoscope navigation. However, obtaining a complete 3-D airway tree structure from a CT volume is quite challenging. Several researchers have proposed automated algorithms basically based on region growing and machine learning techniques. However these methods failed to detect the peripheral bronchi branches. They caused a large amount of leakage. This paper presents a novel approach that permits more accurate extraction of complex bronchial airway region. Our method are composed of three steps. First, the Hessian analysis is utilized for enhancing the line-like structure in CT volumes, then a multiscale cavity-enhancement filter is employed to detect the cavity-like structure from the previous enhanced result. In the second step, we utilize the support vector machine (SVM) to construct a classifier for removing the FP regions generated. Finally, the graph-cut algorithm is utilized to connect all of the candidate voxels to form an integrated airway tree. We applied this method to sixteen cases of 3D chest CT volumes. The results showed that the branch detection rate of this method can reach about 77.7% without leaking into the lung parenchyma areas.

Laparoscopic Adjustable Gastric Band (LAGB) Migration - Endoscopic Treatment Modalities.

PubMed

Klimczak, Tomasz; Szewczyk, Tomasz; Janczak, Przemysław; Jurałowicz, Piotr

2016-12-01

Laparoscopic adjustible gastric binding (LAGB) is one of most common surgical methods of treating obesity. Gastric band migration (erosion) is a typical LAGB complication, with a frequency of about 1-4%. The aim of the study was to present the possibilities of endoscopic diagnosis and treatment of this complication. The study was carried out in the Department of Gastroenterological, Oncological and General Surgery in Łódź. Between 2008 and 2015, 450 gastric bands were implanted using the laparoscopic technique in 318 (71%) women and 132 (29%) men. In this period 7 cases of band migration were diagnosed - 3 cases in men (2.3%) and 4 cases in women (1.3%), what presents 1.56% of general number of complications. Five out of 7 eroded bands were qualified for endoscopic removal. Four out of 5 qualified eroded bands were removed using the gastric band cutting technique. In one case we used the musculo-mucosal incision technique. In order to diagnose early perforations all patients underwent control passage examinations with oral contrast (gastrografin) 3-6 hours after the procedure. All 5 out of 5 qualified eroded gastric bands were successfully removed with the endoscopic method, which gives 100% success rate in own material. Two endoscopic methods were used: 1) endoscopic gastric band cutting, 2) endoscopic musculo-mucosal incision. Endoscopy gives a possibility of instant diagnosis of gastric band migration and early minimally invasive treatment. One of our endoscopic methods of removing the bands by making several incisions of the musculo-mucosal plicae has not yet been described in professional medical literature.

Determining the Optimum Cut-Off Grades in Sulfide Copper Deposits / Określanie Optymalnej Wartości Odcięcia Zawartości Procentowej Pierwiastka Użytecznego W Złożach Siarczku Miedzi

NASA Astrophysics Data System (ADS)

Rahimi, Esmaeil; Oraee, Kazem; Shafahi, Zia Aldin; Ghasemzadeh, Hasan

2015-03-01

Optimum cut-off grades determination in mining life affects production planning and ultimate pit limit and it is also important from social, economical and environmental aspects. Calculation of optimum cut-off grades has been less considered for mines containing various mineral processing methods. In this paper, an optimization technique is applied to obtain optimum cut-off grades for both concentration and heap leaching processes. In this technique, production costs and different recoveries of heap leaching method directed into modeling different annual cash flows in copper mines. Considering the governing constraints, the Lagrange multiplier method is practiced to optimize the cut-off grades in which the objective function is supposed to maximize Net Present Value. The results indicate the effect of heap leaching process on the optimum cut-off grades of primary and secondary sulfide deposits. Określanie optymalnego poziomu odcięcia dla zawartości procentowej pierwiastka użytecznego ma poważny wpływ na planowanie produkcji, określanie ostatecznych limitów zasobów złoża; jest to także ważna kwestia z punktu widzenia kwestii społecznych, ekonomicznych i środowiskowych. Obliczanie optymalnego poziomu odcięcia dla zawartości procentowej pierwiastka użytecznego nie było zwykle szeroko rozważane w przypadku kopalni prowadzących ciągły system przeróbki. W pracy tej przedstawiono technikę optymalizacji określania poziomu zawartości procentowej pierwiastka użytecznego z uwzględnieniem zarówno procesów koncentracji jak i ługowania. W metodzie uwzględniono koszty produkcji i różne wskaźniki odzysku rudy, wielkości te wykorzystane zostały do modelowania rocznych przepływów gotówki w kopalniach miedzi. Uwzględniając narzucone ograniczenia, zastosowano metodę mnożników Lagrange'a w celu optymalizacji określania poziomu zawartości procentowej pierwiastka użytecznego, gdzie przyjętą funkcją celu jest maksymalizacja wartości bieżącej netto. Wyniki wskazują wpływ procesów ługowania na zawartość procentową pierwiastka użytecznego w rudzie pochodzącej z pierwotnych lub wtórnych złóż siarczku miedzi.

Study on the surface constitute properties of high-speed end milling aluminum alloy

NASA Astrophysics Data System (ADS)

Huang, Xiaoming; Li, Hongwei; Yumeng, Ma

2017-09-01

The physical and mechanical properties of the metal surface will change after the metal cutting processing. The comprehensive study of the influence of machining parameters on surface constitute properties are necessary. A high-speed milling experiment by means of orthogonal method with four factors was conducted for aluminum alloy7050-T7451. The surface constitutive properties of the Al-Alloy surface were measured using SSM-B4000TM stress-strain microprobe system. Based on all the load-depth curves obtained, the characteristics parameters such as strain hardening exponent n and yield strength σy of the milling surface are calculated. The effect of cutting speed, feed rate, and width and depth of cut on n and σy was investigated using the ANOVA techniques. The affecting degree of milling parameters on n and σy was v>fz> ap < ae. The influence of milling parameters on n and σ y was described and discussed.

Descriptive Analysis of In Vitro Cutting of Swine Mitral Cusps: Comparison of High-Power Laser and Scalpel Blade Cutting Techniques.

PubMed

Pinto, Nathali Cordeiro; Pomerantzeff, Pablo Maria Alberto; Deana, Alessandro; Zezell, Denise; Benetti, Carolina; Aiello, Vera Demarchi; Lopes, Luciana Almeida; Jatene, Fabio Biscegli; Chavantes, M Cristina

2017-02-01

The most common injury to the heart valve with rheumatic involvement is mitral stenosis, which is the reason for a big number of cardiac operations in Brazil. Commissurotomy is the traditional technique that is still widely used for this condition, although late postoperative restenosis is concerning. This study's purpose was to compare the histological findings of porcine cusp mitral valves treated in vitro with commissurotomy with a scalpel blade to those treated with high-power laser (HPL) cutting, using appropriate staining techniques. Five mitral valves from healthy swine were randomly divided into two groups: Cusp group (G1), cut with a scalpel blade (n = 5), and Cusp group (G2), cut with a laser (n = 5). G2 cusps were treated using a diode laser (λ = 980 nm, power = 9.0 W, time = 12 sec, irradiance = 5625 W/cm 2 , and energy = 108 J). In G1, no histological change was observed in tissue. A hyaline basophilic aspect was focally observed in G2, along with a dark red color on the edges and areas of lower birefringence, when stained with hematoxylin-eosin, Masson's trichrome, and Sirius red. Further, the mean distances from the cutting edge in cusps submitted to laser application and stained with Masson's trichrome and Sirius red were 416.7 and 778.6 μm, respectively, never overcoming 1 mm in length. Thermal changes were unique in the group submitted to HPL and not observed in the cusp group cut with a scalpel blade. The mean distance of the cusps' collagen injury from the cutting edge was less than 1 mm with laser treatment. Additional studies are needed to establish the histological evolution of the laser cutting and to answer whether laser cutting may avoid valvular restenosis better than blade cutting.

Experimental study of various techniques to protect ice-rich cut slopes.

DOT National Transportation Integrated Search

2014-08-01

Cut slopes are usually required to achieve roadway design grades in the ice-rich permafrost areas in Alaska. However, excavation and exposure of a cut slope destroy the existing thermal balance and result in degradation of ice-rich permafrost. Enviro...

Temperature-controlled two-wavelength laser soldering of tissues.

PubMed

Gabay, Ilan; Abergel, Avraham; Vasilyev, Tamar; Rabi, Yaron; Fliss, Dan M; Katzir, Abraham

2011-11-01

Laser tissue soldering is a method for bonding of incisions in tissues. A biological solder is spread over the cut, laser radiation heats the solder and the underlying cut edges and the incision is bonded. This method offers many advantages over conventional techniques (e.g., sutures). Past researches have shown that laser soldering, using a single laser, does not provide sufficient strength for bonding of cuts in thick (>1 mm) tissues. This study introduces a novel method for laser soldering of thick tissues, under temperature control, using two lasers, emitting two different wavelengths. An experimental system was built, using two lasers: (i) a CO(2) laser, whose radiation heated the upper surface of the tissue and (ii) a GaAs laser that heated an albumin layer under the tissue. An infrared fiber-optic radiometer monitored the temperature of the tissue. All three devices were connected to a computer that controlled the process. A computer simulation was written to optimize the system parameters. The system was tested on tissue phantoms, to validate the simulation and ensure that both the upper and lower sides of the cut were heated, and that the temperature could be controlled on both sides. The system was then used ex vivo to bond longitudinal cuts of lengths ∼12 mm in the esophagi of large farm pigs. The theoretical simulations showed a good stabilization of the temperatures at the upper and lower tissue surfaces at the target values. Experiments on tissue phantom showed a good agreement with these simulations. Incisions in esophagi, removed from large farm pigs, were then successfully bonded. The mean burst pressure was ∼3.6 m of water. This study demonstrated the capability of soldering cuts in thick tissues, paving the way for new types of surgical applications. Copyright © 2010 Wiley Periodicals, Inc.

A fully-automated multiscale kernel graph cuts based particle localization scheme for temporal focusing two-photon microscopy

NASA Astrophysics Data System (ADS)

Huang, Xia; Li, Chunqiang; Xiao, Chuan; Sun, Wenqing; Qian, Wei

2017-03-01

The temporal focusing two-photon microscope (TFM) is developed to perform depth resolved wide field fluorescence imaging by capturing frames sequentially. However, due to strong nonignorable noises and diffraction rings surrounding particles, further researches are extremely formidable without a precise particle localization technique. In this paper, we developed a fully-automated scheme to locate particles positions with high noise tolerance. Our scheme includes the following procedures: noise reduction using a hybrid Kalman filter method, particle segmentation based on a multiscale kernel graph cuts global and local segmentation algorithm, and a kinematic estimation based particle tracking method. Both isolated and partial-overlapped particles can be accurately identified with removal of unrelated pixels. Based on our quantitative analysis, 96.22% isolated particles and 84.19% partial-overlapped particles were successfully detected.

[Measurement and estimation methods and research progress of snow evaporation in forests].

PubMed

Li, Hui-Dong; Guan, De-Xin; Jin, Chang-Jie; Wang, An-Zhi; Yuan, Feng-Hui; Wu, Jia-Bing

2013-12-01

Accurate measurement and estimation of snow evaporation (sublimation) in forests is one of the important issues to the understanding of snow surface energy and water balance, and it is also an essential part of regional hydrological and climate models. This paper summarized the measurement and estimation methods of snow evaporation in forests, and made a comprehensive applicability evaluation, including mass-balance methods (snow water equivalent method, comparative measurements of snowfall and through-snowfall, snow evaporation pan, lysimeter, weighing of cut tree, weighing interception on crown, and gamma-ray attenuation technique) and micrometeorological methods (Bowen-ratio energy-balance method, Penman combination equation, aerodynamics method, surface temperature technique and eddy covariance method). Also this paper reviewed the progress of snow evaporation in different forests and its influencal factors. At last, combining the deficiency of past research, an outlook for snow evaporation rearch in forests was presented, hoping to provide a reference for related research in the future.

A particle finite element method for machining simulations

NASA Astrophysics Data System (ADS)

Sabel, Matthias; Sator, Christian; Müller, Ralf

2014-07-01

The particle finite element method (PFEM) appears to be a convenient technique for machining simulations, since the geometry and topology of the problem can undergo severe changes. In this work, a short outline of the PFEM-algorithm is given, which is followed by a detailed description of the involved operations. The -shape method, which is used to track the topology, is explained and tested by a simple example. Also the kinematics and a suitable finite element formulation are introduced. To validate the method simple settings without topological changes are considered and compared to the standard finite element method for large deformations. To examine the performance of the method, when dealing with separating material, a tensile loading is applied to a notched plate. This investigation includes a numerical analysis of the different meshing parameters, and the numerical convergence is studied. With regard to the cutting simulation it is found that only a sufficiently large number of particles (and thus a rather fine finite element discretisation) leads to converged results of process parameters, such as the cutting force.

How to Avoid Cast Saw Complications.

PubMed

Halanski, Matthew A

2016-06-01

As casts are routinely used in pediatric orthopaedics, casts saws are commonly used to remove such casts. Despite being a viewed as the "conservative" and therefore often assumed safest treatment modality, complications associated with the use of casts and cast saws occur. In this manuscript, we review the risk factors associated with cast saw injuries. Cast saw injuries are thermal or abrasive (or both) in nature. Thermal risk factors include: cast saw specifications (including a lack of attached vacuum), use of a dull blade, cutting in a concavity, too thin padding, and overly thick casting materials. Risk factors associated with abrasive injuries include: sharp blades, thin padding, and cutting over boney prominences. Because nearly all clinicians contact the skin with the blade during cast removal, appropriate "in-out technique" is critical. Such technique prevents a hot blade from remaining in contact with the skin for any significant time, diminishing the risk of burn. Similarly, using such technique prevents "dragging the blade" that may pull the skin taught, cutting it. It may be useful to teach proper technique as perforating a cast rather than cutting a cast.

Swept Impact Seismic Technique (SIST)

USGS Publications Warehouse

Park, C.B.; Miller, R.D.; Steeples, D.W.; Black, R.A.

1996-01-01

A coded seismic technique is developed that can result in a higher signal-to-noise ratio than a conventional single-pulse method does. The technique is cost-effective and time-efficient and therefore well suited for shallow-reflection surveys where high resolution and cost-effectiveness are critical. A low-power impact source transmits a few to several hundred high-frequency broad-band seismic pulses during several seconds of recording time according to a deterministic coding scheme. The coding scheme consists of a time-encoded impact sequence in which the rate of impact (cycles/s) changes linearly with time providing a broad range of impact rates. Impact times used during the decoding process are recorded on one channel of the seismograph. The coding concept combines the vibroseis swept-frequency and the Mini-Sosie random impact concepts. The swept-frequency concept greatly improves the suppression of correlation noise with much fewer impacts than normally used in the Mini-Sosie technique. The impact concept makes the technique simple and efficient in generating high-resolution seismic data especially in the presence of noise. The transfer function of the impact sequence simulates a low-cut filter with the cutoff frequency the same as the lowest impact rate. This property can be used to attenuate low-frequency ground-roll noise without using an analog low-cut filter or a spatial source (or receiver) array as is necessary with a conventional single-pulse method. Because of the discontinuous coding scheme, the decoding process is accomplished by a "shift-and-stacking" method that is much simpler and quicker than cross-correlation. The simplicity of the coding allows the mechanical design of the source to remain simple. Several different types of mechanical systems could be adapted to generate a linear impact sweep. In addition, the simplicity of the coding also allows the technique to be used with conventional acquisition systems, with only minor modifications.

Use of coolant for high-speed tooth preparation: a survey of pediatric dentistry residency program directors in the United States.

PubMed

Kupietzky, Ari; Vargas, Karen G; Waggoner, William F; Fuks, Anna B

2010-01-01

To determine current teaching policies regarding the use of coolant type during tooth preparation with high-speed hand-pieces in pediatric dental residency programs in the US. A 17-question survey was electronically mailed to 63 program directors with one follow-up. Multiple-choice questions asked about school and program teaching of cavity preparation with or without water coolant, including hypothetical clinical situations. Fifty-two (83%) program directors returned the survey. Fifty-two percent taught both dry and water coolant methods, 6% taught dry cutting exclusively, and 42% did not teach the dry method and always used water coolant. Dry techniques were used primarily for special needs patients with poor swallow reflexes (50%) and for young children undergoing sedation (41%). Air coolant was taught more frequently in programs in the Midwest (77%) and South (85%) vs. the Northeast (32%) and West (50%) (P<.01). Forty-four percent of combined programs and 60% of hospital programs taught water spray use exclusively, while all university programs taught the dry cutting technique (P<.01). A majority of program directors teach the use of air coolant alone for high-speed preparation of teeth. University and combined programs were more likely to teach the method compared with hospital based ones.

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.

From Agrobacterium to viral vectors: genome modification of plant cells by rare cutting restriction enzymes.

PubMed

Marton, Ira; Honig, Arik; Omid, Ayelet; De Costa, Noam; Marhevka, Elena; Cohen, Barry; Zuker, Amir; Vainstein, Alexander

2013-01-01

Researchers and biotechnologists require methods to accurately modify the genome of higher eukaryotic cells. Such modifications include, but are not limited to, site-specific mutagenesis, site-specific insertion of foreign DNA, and replacement and deletion of native sequences. Accurate genome modifications in plant species have been rather limited, with only a handful of plant species and genes being modified through the use of early genome-editing techniques. The development of rare-cutting restriction enzymes as a tool for the induction of site-specific genomic double-strand breaks and their introduction as a reliable tool for genome modification in animals, animal cells and human cell lines have paved the way for the adaptation of rare-cutting restriction enzymes to genome editing in plant cells. Indeed, the number of plant species and genes which have been successfully edited using zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and engineered homing endonucleases is on the rise. In our review, we discuss the basics of rare-cutting restriction enzyme-mediated genome-editing technology with an emphasis on its application in plant species.

Cutting efficiency of four different rotary nickel: Titanium instruments

PubMed Central

Cecchin, Doglas; de Sousa-Neto, Manoel Damião; Pécora, Jesus Djalma; Gariba-Silva, Ricardo

2011-01-01

Aim: The aim of this study was to evaluate the cutting efficiency of rotary nickel-titanium (NiTi) instruments K3, NiTi Tee, Profile, and Quantec with taper size 04/25. Materials and Methods: The number of samples was 10 for each group (n = 10). The cutting efficiency was measured by the mass loss from each acrylic resin block after instrumentation of a simulated canal using the Crown-down technique. Results: The analysis of variance (ANOVA) showed that there was a statistically significant difference among the studied groups. The Tukey's test showed that the acrylic resin blocks prepared with instruments K3 (0.00369 ± 0.00022), NiTi Tee (0.00368 ± 0.00023), and Profile (0.00351 ± 0.00026) presented the greatest mass loss, showing no statistically significant difference among them (P < 0.05). The lowest mass loss was found in the blocks prepared with Quantec instruments (0.00311 ± 0.0003) (P < 0.05). Conclusions: It could be concluded that the K3, NiTi Tee, and Profile instruments presented a greater cutting efficiency than the Quantec instruments. PMID:21814349

Improved arthroscopic one-piece excision technique for the treatment of symptomatic discoid medial meniscus.

PubMed

Wang, Hong-De; Li, Tong; Gao, Shi-Jun

2017-10-30

Discoid medial meniscus is an extremely rare abnormality of the knee. During arthroscopic meniscectomy for symptomatic discoid medial meniscus, it is difficult to remove the posterior portion of the meniscus because of the confined working space within the compartment and the obstruction caused by the anterior cruciate ligament and the tibial intercondylar eminence. To overcome these problems, we describe an improved arthroscopic technique for one-piece excision of symptomatic discoid medial meniscus through three unique portals. Three improved portals were made in the injured knee: a standard anteromedial portal, a central transpatellar tendon portal, and a high anterolateral portal. The anterior side of the discoid medial meniscus was cut 7 mm from the periphery of the meniscus. Next, the anterior portion of the free discoid meniscus fragment was pulled in the anterolateral direction with tension. A curve-shaped cut was made along the longitudinal tear to the posterior horn using basket forceps through the standard anteromedial portal. Then, the anterior portion of the free discoid meniscus was pulled in the anteromedial direction. Pulling the fragment under tension made it easier to cut the posterior side of the discoid meniscus. The posterior side of the discoid meniscus was cut 7 mm from the periphery of the meniscus with straight scissors or basket forceps through the central transpatellar tendon portal. This technique resulted in satisfactory results. Excellent visualization of the posterior part of the discoid medial meniscus was gained during the procedure, and it was easy to cut the posterior part of the discoid medial meniscus. No recurrent symptoms were found. This improved arthroscopic one-piece excision technique for the treatment of symptomatic discoid medial meniscus enables the posterior part of the meniscus to be cut satisfactorily. Moreover, compared with previous techniques, this novel technique causes less formation of foreign bodies and less damage to the anterior cruciate ligament, medial collateral ligament, and cartilage and requires a shorter procedural time.

X-Z-Theta cutting method

DOEpatents

Bieg, Lothar 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.

Synthesis and characterization of polycrystalline CdSiP2

NASA Astrophysics Data System (ADS)

Bereznaya, S. A.; Korotchenko, Z. V.; Sarkisov, S. Yu; Korolkov, I. V.; Kuchumov, B. M.; Saprykin, A. I.; Atuchin, V. V.

2018-05-01

A modified method is proposed for the CdSiP2 compound synthesis from elemental starting components. The developed technique allows completing the synthesis process within 30 h. The phase and chemical composition of the synthesized material were confirmed by the x-ray diffraction analysis and scanning electron microscopy with energy-dispersive spectroscopy. The transparent crystal block sized 3 × 3 × 2 mm3 was cut from the polycrystalline ingot and characterized by optical methods.

Language study on Spliced Semigraph using Folding techniques

NASA Astrophysics Data System (ADS)

Thiagarajan, K.; Padmashree, J.

2018-04-01

In this paper, we proposed algorithm to identify cut vertices and cut edges for n-Cut Spliced Semigraph and splicing the n-Cut Spliced Semigraph using cut vertices else cut edges or combination of cut vertex and cut edge and applying sequence of folding to the spliced semigraph to obtain the semigraph quadruple η(S)=(2, 1, 1, 1). We observed that the splicing and folding using both cut vertices and cut edges is applicable only for n-Cut Spliced Semigraph where n > 2. Also, we transformed the spliced semigraph into tree structure and studied the language for the semigraph with n+2 vertices and n+1 semivertices using Depth First Edge Sequence algorithm and obtain the language structure with sequence of alphabet ‘a’ and ‘b’.

Comparison of Numerical Modeling Methods for Soil Vibration Cutting

NASA Astrophysics Data System (ADS)

Jiang, Jiandong; Zhang, Enguang

2018-01-01

In this paper, we studied the appropriate numerical simulation method for vibration soil cutting. Three numerical simulation methods, commonly used for uniform speed soil cutting, Lagrange, ALE and DEM, are analyzed. Three models of vibration soil cutting simulation model are established by using ls-dyna.The applicability of the three methods to this problem is analyzed in combination with the model mechanism and simulation results. Both the Lagrange method and the DEM method can show the force oscillation of the tool and the large deformation of the soil in the vibration cutting. Lagrange method shows better effect of soil debris breaking. Because of the poor stability of ALE method, it is not suitable to use soil vibration cutting problem.

Arthroscopic Double-Row Transosseous Equivalent Rotator Cuff Repair with a Knotless Self-Reinforcing Technique

PubMed Central

Mook, William R.; Greenspoon, Joshua A.; Millett, Peter J.

2016-01-01

Background: Rotator cuff tears are a significant cause of shoulder morbidity. Surgical techniques for repair have evolved to optimize the biologic and mechanical variables critical to tendon healing. Double-row repairs have demonstrated superior biomechanical advantages to a single-row. Methods: The preferred technique for rotator cuff repair of the senior author was reviewed and described in a step by step fashion. The final construct is a knotless double row transosseous equivalent construct. Results: The described technique includes the advantages of a double-row construct while also offering self reinforcement, decreased risk of suture cut through, decreased risk of medial row overtensioning and tissue strangulation, improved vascularity, the efficiency of a knotless system, and no increased risk for subacromial impingement from the burden of suture knots. Conclusion: Arthroscopic knotless double row rotator cuff repair is a safe and effective method to repair rotator cuff tears. PMID:27733881

Multiple sclerosis lesion segmentation using an automatic multimodal graph cuts.

PubMed

García-Lorenzo, Daniel; Lecoeur, Jeremy; Arnold, Douglas L; Collins, D Louis; Barillot, Christian

2009-01-01

Graph Cuts have been shown as a powerful interactive segmentation technique in several medical domains. We propose to automate the Graph Cuts in order to automatically segment Multiple Sclerosis (MS) lesions in MRI. We replace the manual interaction with a robust EM-based approach in order to discriminate between MS lesions and the Normal Appearing Brain Tissues (NABT). Evaluation is performed in synthetic and real images showing good agreement between the automatic segmentation and the target segmentation. We compare our algorithm with the state of the art techniques and with several manual segmentations. An advantage of our algorithm over previously published ones is the possibility to semi-automatically improve the segmentation due to the Graph Cuts interactive feature.

The investigation of trapped thickness shear modes in a contoured AT-cut quartz plate using the power series expansion technique

NASA Astrophysics Data System (ADS)

Li, Peng; Jin, Feng

2018-01-01

The dynamic model about the anti-plane vibration of a contoured quartz plate with thickness changing continuously is established by ignoring the effect of small elastic constant c 56. The governing equation is solved using the power series expansion technique, and the trapped thickness shear modes caused by bulge thickness are revealed. Theoretically, the proposed method is more general, which can be capable of handling various thickness profiles defined mathematically. After the convergence of the series is demonstrated and the correctness is numerically validated with the aid of finite element method results, systematic parametric studies are subsequently carried out to quantify the effects of the geometry parameter upon the trapped modes, including resonant frequency and mode shape. After that, the band structures of thickness shear waves propagation in a periodically contoured quartz plate, as well as the power transmission spectra, are obtained based on the power series expansion technique. It is revealed that broad stop bands below cut-off frequency exist owing to the trapped modes excited by the geometry inhomogeneity, which has little relationship with the structural periodicity, and its physical mechanism is different from the Bragg scattering effect. The outcome is widely applicable, and can be utilized to provide theoretical and practical guidance for the design and manufacturing of quartz resonators and wave filters.

An Undergraduate Investigation into the 10-23 DNA Enzyme that Cleaves RNA: DNA Can Cut It in the Biochemistry Laboratory

ERIC Educational Resources Information Center

Flynn-Charlebois, Amber; Burns, Jamie; Chapelliquen, Stephanie; Sanmartino, Holly

2011-01-01

A low-cost biochemistry experiment is described that demonstrates current techniques in the use of catalytic DNA molecules and introduces a nonradioactive, nonfluorescent, inexpensive, fast, and safe method for monitoring these nucleic acid reactions. The laboratory involves the exploration of the 10-23 DNA enzyme as it cleaves a specific RNA…

[Progress in industrial bioprocess engineering in China].

PubMed

Zhuang, Yingping; Chen, Hongzhang; Xia, Jianye; Tang, Wenjun; Zhao, Zhimin

2015-06-01

The advances of industrial biotechnology highly depend on the development of industrial bioprocess researches. In China, we are facing several challenges because of a huge national industrial fermentation capacity. The industrial bioprocess development experienced several main stages. This work mainly reviews the development of the industrial bioprocess in China during the past 30 or 40 years: including the early stage kinetics model study derived from classical chemical engineering, researching method based on control theory, multiple-parameter analysis techniques of on-line measuring instruments and techniques, and multi-scale analysis theory, and also solid state fermentation techniques and fermenters. In addition, the cutting edge of bioprocess engineering was also addressed.

Cut-it-out technique for ocular fish-hook injury.

PubMed

Ahmad, Syed Shoeb; Seng, Chiang Wai; Ghani, Shuaibah Abdul; Lee, Jane F

2013-10-01

An 11-year-old boy was involved in an injury with a fish-hook to his eye. The hook had impaled itself to the cornea and deeper structures. There was associated corneal edema and hyphema, making visualization difficult. In this case, we performed the unusual "cut-it-out" technique to remove the hook from the eye.

Thin layer chromatography-ion mobility spectrometry (TLC-IMS).

PubMed

Ilbeigi, Vahideh; Tabrizchi, Mahmoud

2015-01-06

Ion mobility spectrometry (IMS) is a fast and sensitive analytical method which operates at the atmospheric pressure. To enhance the capability of IMS for the analysis of mixtures, it is often used with preseparation techniques, such as GC or HPLC. Here, we report for the first time the coupling of the thin-layer chromatography and IMS. A variety of coupling schemes were tried that included direct electrospray from the TLC strip tip, indirect electrospray from a needle connected to the TLC strip, introducing the moving solvent into the injection port, and, the simplest way, offline introduction of scratched or cut pieces of strips into the IMS injection port. In this study a special solvent tank was designed and the TLC strip was mounted horizontally where the solvent would flow down. A very small funnel right below the TLC tip collected the solvent and transferred it to a needle via a capillary tubing. Using the TLC-ESI-IMS technique, acceptable separations were achieved for two component mixtures of morphine-papaverine and acridine-papaverine. A special injection port was designed to host the pieces cut off the TLC. The method was successfully used to identify each spot on the TLC by IMS in a few seconds.

Into the development of a model to assess beam shaping and polarization control effects on laser cutting

NASA Astrophysics Data System (ADS)

Rodrigues, Gonçalo C.; Duflou, Joost R.

2018-02-01

This paper offers an in-depth look into beam shaping and polarization control as two of the most promising techniques for improving industrial laser cutting of metal sheets. An assessment model is developed for the study of such effects. It is built upon several modifications to models as available in literature in order to evaluate the potential of a wide range of considered concepts. This includes different kinds of beam shaping (achieved by extra-cavity optical elements or asymmetric diode staking) and polarization control techniques (linear, cross, radial, azimuthal). A fully mathematical description and solution procedure are provided. Three case studies for direct diode lasers follow, containing both experimental data and parametric studies. In the first case study, linear polarization is analyzed for any given angle between the cutting direction and the electrical field. In the second case several polarization strategies are compared for similar cut conditions, evaluating, for example, the minimum number of spatial divisions of a segmented polarized laser beam to achieve a target performance. A novel strategy, based on a 12-division linear-to-radial polarization converter with an axis misalignment and capable of improving cutting efficiency with more than 60%, is proposed. The last case study reveals different insights in beam shaping techniques, with an example of a beam shape optimization path for a 30% improvement in cutting efficiency. The proposed techniques are not limited to this type of laser source, neither is the model dedicated to these specific case studies. Limitations of the model and opportunities are further discussed.

The LS-STAG immersed boundary method for non-Newtonian flows in irregular geometries: flow of shear-thinning liquids between eccentric rotating cylinders

NASA Astrophysics Data System (ADS)

Botella, Olivier; Ait-Messaoud, Mazigh; Pertat, Adrien; Cheny, Yoann; Rigal, Claire

2015-04-01

This paper presents the extension of a well-established immersed boundary/cut-cell method, the LS-STAG method (Cheny and Botella in J Comput Phys 229:1043-1076, 2010), to non-Newtonian flow computations in 2D irregular geometries. One of the distinguished features of our IB method is to use level-set techniques in the cut-cells near the irregular boundary, where accurate discretization is of paramount importance for stability and accuracy of the computations. For this purpose, we present here an accurate discretization of the velocity gradients and shear rate in the cut-cells that fits elegantly in the framework of the velocity-pressure-stress staggered arrangement and the special quadratures developed previously for viscoelastic flows. After assessing the accuracy of the discretization on a benchmark solution for power-law fluids, the LS-STAG code is applied to the flow of various shear-thinning xanthan solutions in a wide-gap, non-coaxial, Taylor-Couette reactor for which rheological characterization, experimental flow measurements (PIV) and FLUENT simulations have recently been performed in our group. Our numerical investigation will give new insight on the flow patterns (onset, size and position of the recirculation zone) and will firmly correlate them to global flow properties such as shear-thinning index, generalized Reynolds number and torque ratio at the cylinders.

Evaluation of predictive capacities of biomarkers based on research synthesis.

PubMed

Hattori, Satoshi; Zhou, Xiao-Hua

2016-11-10

The objective of diagnostic studies or prognostic studies is to evaluate and compare predictive capacities of biomarkers. Suppose we are interested in evaluation and comparison of predictive capacities of continuous biomarkers for a binary outcome based on research synthesis. In analysis of each study, subjects are often classified into two groups of the high-expression and low-expression groups according to a cut-off value, and statistical analysis is based on a 2 × 2 table defined by the response and the high expression or low expression of the biomarker. Because the cut-off is study specific, it is difficult to interpret a combined summary measure such as an odds ratio based on the standard meta-analysis techniques. The summary receiver operating characteristic curve is a useful method for meta-analysis of diagnostic studies in the presence of heterogeneity of cut-off values to examine discriminative capacities of biomarkers. We develop a method to estimate positive or negative predictive curves, which are alternative to the receiver operating characteristic curve based on information reported in published papers of each study. These predictive curves provide a useful graphical presentation of pairs of positive and negative predictive values and allow us to compare predictive capacities of biomarkers of different scales in the presence of heterogeneity in cut-off values among studies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Use of non-standardised micro-destructive techniques in the characterization of traditional construction materials

NASA Astrophysics Data System (ADS)

Ioannou, Ioannis; Theodoridou, Magdalini; Modestou, Sevasti; Fournari, Revecca; Dagrain, Fabrice

2013-04-01

The characterization of material properties and the diagnosis of their state of weathering and conservation are three of the most important steps in the field of cultural heritage preservation. Several standardised experimental methods exist, especially for determining the material properties and their durability. However, they are limited in their application by the required size of test specimens and the controlled laboratory conditions needed to undertake the tests; this is especially true when the materials under study constitute immovable parts of heritage structures. The current use of other advanced methods of analysis, such as imaging techniques, in the aforementioned field of research offers invaluable results. However, these techniques may not always be accessible to the wider research community due to their complex nature and relatively high cost of application. This study presents innovative applications of two recently developed cutting techniques; the portable Drilling Resistance Measuring System (DRMS) and the scratch tool. Both methods are defined as micro-destructive, since they only destroy a very small portion of sample material. The general concept of both methods lies within the forces needed to cut a material by linear (scratch tool) or rotational (DRMS) cutting action; these forces are related to the mechanical properties of the material and the technological parameters applied on the tool. Therefore, for a given testing configuration, the only parameter influencing the forces applied is the strength of the material. These two techniques have been used alongside a series of standardised laboratory tests aiming at the correlation of various stone properties (density, porosity, dynamic elastic modulus and uniaxial compressive strength). The results prove the potential of both techniques in assessing the uniaxial compressive strength of stones. The scratch tool has also been used effectively to estimate the compressive strength of mud bricks. It therefore follows that both micro-destructive techniques may prove useful in the physico-mechanical characterization of materials which demand in-situ measurements or allow very limited sampling. Moreover, both techniques have been used, for the first time, to map the distribution of salts in building stone in the laboratory; micro-drilling was also applied in the same context in-situ. The results of the laboratory tests performed on limestone impregnated with sodium and magnesium sulfate confirm that both the scratch tool and the DRMS may successfully detect the location of the salt front, as they respond to pore clogging by salt crystals by providing increased scratching/drilling resistance values. Drilling and scratching of duplicate samples treated with a hydrophobic product show the sensitivity of both techniques as they clearly detect changes to the salt front location (i.e. cryptoflorescence) caused by surface treatments. Both techniques were also successful in highlighting the difference in the crystallisation location and pattern of magnesium sulphate and sodium chloride. In-situ application of the micro-drilling test demonstrated its potential for use in the assessment of masonry salt weathering; the results suggest that this technique may, in fact, be useful as a preventive measure against salt damage. Last but not least, both aforementioned novel micro-destructive techniques have been used to assess the effectiveness of commercially available consolidants. The results of the scratch tool have also been utilised to develop a tomography image of the samples under test. Scratching tomography may potentially be combined with in-situ micro-drilling tests to evaluate the effectiveness of consolidation treatments applied on monuments and historic buildings.

Easy and Inexpensive Technique for Removal of Round Headed, Jammed Locking Screws in Distal Tibial Interlocking Plate.

PubMed

Singh, Harpreet; Sharma, Rohit; Gupta, Sachin; Singh, Narinderjit; Singh, Simarpreet

2015-01-01

The advent of locking plates has brought new problems in implant removal. Difficulty in removing screws from a locking plate is well-known. These difficulties include cold welding between the screw head and locking screw hole, stripping of the recess of the screw head for the screwdriver, and cross-threading between threads in the screw head and screw hole. However, there are cases in which removal is difficult. We describe a new technique for removing a round headed, jammed locking screws from a locking plate. 55 years old male patient received a locking distal tibial plate along with distal fibular plate 3years back from UAE. Now patient came with complaint of non-healing ulcer over medial aspect of lower 1/3rd of right leg from past 1 year. Non operative management did not improve the symptoms. The patient consented to implant removal, with the express understanding that implant removal might be impossible because already one failed attempt had been performed at some other hospital six months back. We then decided to proceed with the new technique. The rest of the proximal screws were removed using a technique not previously described. We used stainless steel metal cutting blades that are used to cut door locks or pad locks to cut the remaining stripped headed screws. This technique is very quick, easy to perform and inexpensive because the metal cutting blades which are used to cut the screws are very cheap. Yet it is very effective technique to remove the stripped headed or jammed locking screws. It is also very less destructive because of very less heat production during the procedure there is no problem of thermal necrosis to the bone or the surrounding soft tissue.

Serial Transmission of Plant Viruses by Cutting During Grafting

USDA-ARS?s Scientific Manuscript database

Reciprocal grafts of two tomato (Solanum lycopersicum L.) cultivars were made by hand using commercial grafting techniques. The razor blade used to cut rootstock or scion was first contaminated by making a single cut on tomato plants infected with either tomato spotted wilt virus (TSWV) or tomato m...

Routine Chest X-ray: Still Valuable for the Assessment of Left Ventricular Size and Function in the Era of Super Machines?

PubMed Central

Morales, Maria-Aurora; Prediletto, Renato; Rossi, Giuseppe; Catapano, Giosuè; Lombardi, Massimo; Rovai, Daniele

2012-01-01

Objectives: The development of technologically advanced, expensive techniques has progressively reduced the value of chest X-ray in clinical practice for the assessment of left ventricular (LV) dilatation and dysfunction. Although controversial data are reported on the role of this widely available technique in cardiac assessment, it is known that the cardio-thoracic ratio is predictive of risk of progression in the NYHA Class, hospitalization, and outcome in patients with LV dysfunction. This study aimed to evaluate the reliability of the transverse diameter of heart shadow [TDH] by chest X-ray for detecting LV dilatation and dysfunction as compared to Magnetic Resonance Imaging (MRI) performed for different clinical reasons. Materials and Methods: In 101 patients, TDH was measured in digital chest X-ray and LV volumes and ejection fraction (EF) by MRI, both exams performed within 2 days. Results: A direct correlation between TDH and end-diastolic volumes (r = .75, P<0.0001) was reported. TDH cut-off values of 14.5 mm in females identified LV end-diastolic volumes >150 mL (sensitivity: 82%, specificity: 69%); in males a cut-off value of 15.5 mm identified LV end-diastolic volumes >210 mL (sensitivity: 84%; specificity: 72%). A negative relation was found between TDH and LVEF (r = -.54, P<0.0001). The above cut-off values of TDH discriminated patients with LV systolic dysfunction – LVEF <35% (sensitivity and specificity: 67% and 57% in females; 76% and 59% in males, respectively). Conclusions: Chest X-ray may still be considered a reliable technique in predicting LV dilatation by the accurate measurement of TDH as compared to cardiac MRI. Technologically advanced, expensive, and less available imaging techniques should be performed on the basis of sound clinical requests. PMID:22754739

Phacoemulsification using a chisel-shaped illuminator: enhanced depth trench, one-shot crack, and phaco cut.

PubMed

Wi, Jaemin; Seo, Hyejin; Lee, Jong Yeon; Nam, Dong Heun

2016-01-01

To evaluate the efficacy and outcomes of intracameral illuminator-assisted nucleofractis technique in cataract surgery. Since June 2012, this novel technique has been performed in all cataract cases by one surgeon (approximately 300 cases of various densities). Trenching continues until the posterior plate white reflex between an endonucleus and an epinucleus is identified (enhanced depth trench). After trenching, cracking is initiated with minimal separation force, and completion of cracking is confirmed by posterior capsule reflex (one-shot crack). With followability enhanced by an elliptical phaco mode, the divided nucleus is efficiently cut into small fragments by a chisel-shaped illuminator (phaco cut). We have not experienced any capsular bag or zonular complications, and the effective phacoemulsification time seemed to be shorter than that with the conventional technique. This technique simplifies the complete division of the nucleus, which is the most challenging step in safe and efficient phacoemulsification.

Achieving Small Structures in Thin NiTi Sheets for Medical Applications with Water Jet and Micro Machining: A Comparison

NASA Astrophysics Data System (ADS)

Frotscher, M.; Kahleyss, F.; Simon, T.; Biermann, D.; Eggeler, G.

2011-07-01

NiTi shape memory alloys (SMA) are used for a variety of applications including medical implants and tools as well as actuators, making use of their unique properties. However, due to the hardness and strength, in combination with the high elasticity of the material, the machining of components can be challenging. The most common machining techniques used today are laser cutting and electrical discharge machining (EDM). In this study, we report on the machining of small structures into binary NiTi sheets, applying alternative processing methods being well-established for other metallic materials. Our results indicate that water jet machining and micro milling can be used to machine delicate structures, even in very thin NiTi sheets. Further work is required to optimize the cut quality and the machining speed in order to increase the cost-effectiveness and to make both methods more competitive.

A simple method of fabricating mask-free microfluidic devices for biological analysis

PubMed Central

Yi, Xin; Kodzius, Rimantas; Gong, Xiuqing; Xiao, Kang; Wen, Weijia

2010-01-01

We report a simple, low-cost, rapid, and mask-free method to fabricate two-dimensional (2D) and three-dimensional (3D) microfluidic chip for biological analysis researches. In this fabrication process, a laser system is used to cut through paper to form intricate patterns and differently configured channels for specific purposes. Bonded with cyanoacrylate-based resin, the prepared paper sheet is sandwiched between glass slides (hydrophilic) or polymer-based plates (hydrophobic) to obtain a multilayer structure. In order to examine the chip’s biocompatibility and applicability, protein concentration was measured while DNA capillary electrophoresis was carried out, and both of them show positive results. With the utilization of direct laser cutting and one-step gas-sacrificing techniques, the whole fabrication processes for complicated 2D and 3D microfluidic devices are shorten into several minutes which make it a good alternative of poly(dimethylsiloxane) microfluidic chips used in biological analysis researches. PMID:20890452

Characterisation of debris from laser and mechanical cutting of bone.

PubMed

Rachmanis, Nikolaos; McGuinness, Garrett B; McGeough, Joseph A

2014-07-01

Laser cutting of bones has been proposed as a technology in orthopaedic surgery. In this short study, the laser-bone interaction was examined using a pulsed erbium-doped yttrium aluminium garnet laser and compared to a conventional cutting technique. Microscopic analysis revealed the nature of waste debris and showed higher proportions of finer particles for conventional sagittal sawing compared to laser cutting. © IMechE 2014.

Pyrotechnic shock: A literature survey of the Linear Shaped Charge (LSC)

NASA Technical Reports Server (NTRS)

Smith, J. L.

1984-01-01

Linear shaped charge (LSC) literature for the past 20 years is reviewed. The following topics are discussed: (1) LSC configuration; (2) LSC usage; (3) LSC induced pyroshock; (4) simulated pyrotechnic testing; (5) actual pyrotechnic testing; (6) data collection methods; (7) data analysis techniques; (8) shock reduction methods; and (9) design criteria. Although no new discoveries have been made in LSC research, charge shapes are improved to allow better cutting performance, testing instrumentation is refined, and some new explosives, for use in LSC, are formulated.

Fractal analysis of INSAR and correlation with graph-cut based image registration for coastline deformation analysis: post seismic hazard assessment of the 2011 Tohoku earthquake region

NASA Astrophysics Data System (ADS)

Dutta, P. K.; Mishra, O. P.

2012-04-01

Satellite imagery for 2011 earthquake off the Pacific coast of Tohoku has provided an opportunity to conduct image transformation analyses by employing multi-temporal images retrieval techniques. In this study, we used a new image segmentation algorithm to image coastline deformation by adopting graph cut energy minimization framework. Comprehensive analysis of available INSAR images using coastline deformation analysis helped extract disaster information of the affected region of the 2011 Tohoku tsunamigenic earthquake source zone. We attempted to correlate fractal analysis of seismic clustering behavior with image processing analogies and our observations suggest that increase in fractal dimension distribution is associated with clustering of events that may determine the level of devastation of the region. The implementation of graph cut based image registration technique helps us to detect the devastation across the coastline of Tohoku through change of intensity of pixels that carries out regional segmentation for the change in coastal boundary after the tsunami. The study applies transformation parameters on remotely sensed images by manually segmenting the image to recovering translation parameter from two images that differ by rotation. Based on the satellite image analysis through image segmentation, it is found that the area of 0.997 sq km for the Honshu region was a maximum damage zone localized in the coastal belt of NE Japan forearc region. The analysis helps infer using matlab that the proposed graph cut algorithm is robust and more accurate than other image registration methods. The analysis shows that the method can give a realistic estimate for recovered deformation fields in pixels corresponding to coastline change which may help formulate the strategy for assessment during post disaster need assessment scenario for the coastal belts associated with damages due to strong shaking and tsunamis in the world under disaster risk mitigation programs.

26 CFR 1.585-7 - Elective cut-off method of changing from the reserve method of section 585.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Elective cut-off method of changing from the... § 1.585-7 Elective cut-off method of changing from the reserve method of section 585. (a) General rule...)) may elect to use the cut-off method set forth in this section. Any such election must be made at the...

An automated repair method of water pipe infrastructure using carbon fiber bundles

NASA Astrophysics Data System (ADS)

Wisotzkey, Sean; Carr, Heath; Fyfe, Ed

2011-04-01

The United States water pipe infrastructure is made up of over 2 million miles of pipe. Due to age and deterioration, a large portion of this pipe is in need of repair to prevent catastrophic failures. Current repair methods generally involve intrusive techniques that can be time consuming and costly, but also can cause major societal impacts. A new automated repair method incorporating innovative carbon fiber technology is in development. This automated method would eliminate the need for trenching and would vastly cut time and labor costs, providing a much more economical pipe repair solution.

Experimental study on internal cooling system in hard turning of HCWCI using CBN tools

NASA Astrophysics Data System (ADS)

Ravi, A. M.; Murigendrappa, S. M.

2018-04-01

In recent times, hard turning became most emerging technique in manufacturing processes, especially to cut high hard materials like high chrome white cast iron (HCWCI). Use of Cubic boron nitride (CBN), pCBN and Carbide tools are most appropriate to shear the metals but are uneconomical. Since hard turning carried out in dry condition, lowering the tool wear by minimizing tool temperature is the only solution. Study reveals, no effective cooling systems are available so for in order to enhance the tool life of the cutting tools and to improve machinability characteristics. The detrimental effect of cutting parameters on cutting temperature is generally controlled by proper selections. The objective of this paper is to develop a new cooling system to control tool tip temperature, thereby minimizing the cutting forces and the tool wear rates. The materials chosen for this work was HCWCI and cutting tools are CBN inserts. Intricate cavities were made on the periphery of the tool holder for easy flow of cold water. Taguchi techniques were adopted to carry out the experimentations. The experimental results confirm considerable reduction in the cutting forces and tool wear rates.

Application of high speed machining technology in aviation

NASA Astrophysics Data System (ADS)

Bałon, Paweł; Szostak, Janusz; Kiełbasa, Bartłomiej; Rejman, Edward; Smusz, Robert

2018-05-01

Aircraft structures are exposed to many loads during their working lifespan. Every particular action made during a flight is composed of a series of air movements which generate various aircraft loads. The most rigorous requirement which modern aircraft structures must fulfill is to maintain their high durability and reliability. This requirement involves taking many restrictions into account during the aircraft design process. The most important factor is the structure's overall mass, which has a crucial impact on both utility properties and cost-effectiveness. This makes aircraft one of the most complex results of modern technology. Additionally, there is currently an increasing utilization of high strength aluminum alloys, which requires the implementation of new manufacturing processes. High Speed Machining technology (HSM) is currently one of the most important machining technologies used in the aviation industry, especially in the machining of aluminium alloys. The primary difference between HSM and other milling techniques is the ability to select cutting parameters - depth of the cut layer, feed rate, and cutting speed in order to simultaneously ensure high quality, precision of the machined surface, and high machining efficiency, all of which shorten the manufacturing process of the integral components. In this paper, the authors explain the implementation of the HSM method in integral aircraft constructions. It presents the method of the airframe manufacturing method, and the final results. The HSM method is compared to the previous method where all subcomponents were manufactured by bending and forming processes, and then, they were joined by riveting.

Human Lumbar Ligamentum Flavum Anatomy for Epidural Anesthesia: Reviewing a 3D MR-Based Interactive Model and Postmortem Samples.

PubMed

Reina, Miguel A; Lirk, Philipp; Puigdellívol-Sánchez, Anna; Mavar, Marija; Prats-Galino, Alberto

2016-03-01

The ligamentum flavum (LF) forms the anatomic basis for the loss-of-resistance technique essential to the performance of epidural anesthesia. However, the LF presents considerable interindividual variability, including the possibility of midline gaps, which may influence the performance of epidural anesthesia. We devise a method to reconstruct the anatomy of the digitally LF based on magnetic resonance images to clarify the exact limits and edges of LF and its different thickness, depending on the area examined, while avoiding destructive methods, as well as the dissection processes. Anatomic cadaveric cross sections enabled us to visually check the definition of the edges along the entire LF and compare them using 3D image reconstruction methods. Reconstruction was performed in images obtained from 7 patients. Images from 1 patient were used as a basis for the 3D spinal anatomy tool. In parallel, axial cuts, 2 to 3 cm thick, were performed in lumbar spines of 4 frozen cadavers. This technique allowed us to identify the entire ligament and its exact limits, while avoiding alterations resulting from cutting processes or from preparation methods. The LF extended between the laminas of adjacent vertebrae at all vertebral levels of the patients examined, but midline gaps are regularly encountered. These anatomical variants were reproduced in a 3D portable document format. The major anatomical features of the LF were reproduced in the 3D model. Details of its structure and variations of thickness in successive sagittal and axial slides could be visualized. Gaps within LF previously studied in cadavers have been identified in our interactive 3D model, which may help to understand their nature, as well as possible implications for epidural techniques.

Indirect questioning method reveals hidden support for female genital cutting in South Central Ethiopia.

PubMed

Gibson, Mhairi A; Gurmu, Eshetu; Cobo, Beatriz; Rueda, María M; Scott, Isabel M

2018-01-01

Female genital cutting (FGC) has major implications for women's physical, sexual and psychological health, and eliminating the practice is a key target for public health policy-makers. To date one of the main barriers to achieving this has been an inability to infer privately-held views on FGC within communities where it is prevalent. As a sensitive (and often illegal) topic, people are anticipated to hide their true support for the practice when questioned directly. Here we use an indirect questioning method (unmatched count technique) to identify hidden support for FGC in a rural South Central Ethiopian community where the practice is common, but thought to be in decline. Employing a socio-demographic household survey of 1620 Arsi Oromo adults, which incorporated both direct and indirect direct response (unmatched count) techniques we compare directly-stated versus privately-held views in support of FGC, and individual variation in responses by age, gender and education and target female (daughters versus daughters-in-law). Both genders express low support for FGC when questioned directly, while indirect methods reveal substantially higher acceptance (of cutting both daughters and daughters-in-law). Educated adults (those who have attended school) are privately more supportive of the practice than they are prepared to admit openly to an interviewer, indicating that education may heighten secrecy rather than decrease support for FGC. Older individuals hold the strongest views in favour of FGC (particularly educated older males), but they are also more inclined to conceal their support for FGC when questioned directly. As these elders represent the most influential members of society, their hidden support for FGC may constitute a pivotal barrier to eliminating the practice in this community. Our results demonstrate the great potential for indirect questioning methods to advance knowledge and inform policy on culturally-sensitive topics like FGC; providing more reliable data and improving understanding of the "true" drivers of FGC.

Clonal propagation on Eucalyptus by cuttings in France

Treesearch

H. Chaperon

1983-01-01

A.FO.CEL has developed a technique for mass propagation by cuttings of Eucalyptus in France. This technique is described from the selection of the ortet to the mass propagation of the clone for afforestation: the first stage is the mobilization of the ortet, the second stage is called pre-propagation which includes rejuvenating and rooting conditioning, the third stage...

Use of schlieren methods to study gas flow in laser technology

NASA Astrophysics Data System (ADS)

Mrňa, Libor; Pavelka, Jan; Horník, Petr; Hrabovský, Jozef

2016-11-01

Laser technologies such as welding and cutting rely on process gases. We suggest to use schlieren imaging to visualize the gas flow during these processes. During the process of laser welding, the shielding gas flows to the welded area to prevent oxidation of the weld pool by surrounding air. The gas also interacts with hot plasma spurting from the key hole induced by the laser beam incident on the molten material. This interaction is quite complicated because hot plasma mixes with the cold shielding gas while the system is moving along the weld. Three shielding gases were used in the presented experiment: Ar, He and N2. Differences in dynamics of the flow are clearly visible on schlieren images. Moreover, high speed recording reveals a structure consisting of hot gas bubbles. We were also able to determine the velocity of the bubbles from the recording. During laser cutting, the process gas flows coaxially with the laser beam from the nozzle to remove the molten material out of the kerf. The gas flow is critical for the quality of the resulting edge of the cut. Schlieren method was used to study gas flow under the nozzle and then under the material being cut. This actually creates another slot nozzle. Due to the very low speed of flow below the material the schleiren method is already at the limit of its sensitivity. Therefore, it is necessary to apply a differential technique to increase the contrast. Distinctive widening of the flow shaped by the kerf was observed.

Angular approach combined to mechanical model for tool breakage detection by eddy current sensors

NASA Astrophysics Data System (ADS)

Ritou, M.; Garnier, S.; Furet, B.; Hascoet, J. Y.

2014-02-01

The paper presents a new complete approach for Tool Condition Monitoring (TCM) in milling. The aim is the early detection of small damages so that catastrophic tool failures are prevented. A versatile in-process monitoring system is introduced for reliability concerns. The tool condition is determined by estimates of the radial eccentricity of the teeth. An adequate criterion is proposed combining mechanical model of milling and angular approach.Then, a new solution is proposed for the estimate of cutting force using eddy current sensors implemented close to spindle nose. Signals are analysed in the angular domain, notably by synchronous averaging technique. Phase shifts induced by changes of machining direction are compensated. Results are compared with cutting forces measured with a dynamometer table.The proposed method is implemented in an industrial case of pocket machining operation. One of the cutting edges has been slightly damaged during the machining, as shown by a direct measurement of the tool. A control chart is established with the estimates of cutter eccentricity obtained during the machining from the eddy current sensors signals. Efficiency and reliability of the method is demonstrated by a successful detection of the damage.

26 CFR 1.669(a)-4 - Tax attributable to short-cut throwback method.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Tax attributable to short-cut throwback method... Taxable Years Beginning Before January 1, 1969 § 1.669(a)-4 Tax attributable to short-cut throwback method... the amounts deemed distributed under section 666 by the short-cut throwback method provided in section...

The UPSF code: a metaprogramming-based high-performance automatically parallelized plasma simulation framework

NASA Astrophysics Data System (ADS)

Gao, Xiatian; Wang, Xiaogang; Jiang, Binhao

2017-10-01

UPSF (Universal Plasma Simulation Framework) is a new plasma simulation code designed for maximum flexibility by using edge-cutting techniques supported by C++17 standard. Through use of metaprogramming technique, UPSF provides arbitrary dimensional data structures and methods to support various kinds of plasma simulation models, like, Vlasov, particle in cell (PIC), fluid, Fokker-Planck, and their variants and hybrid methods. Through C++ metaprogramming technique, a single code can be used to arbitrary dimensional systems with no loss of performance. UPSF can also automatically parallelize the distributed data structure and accelerate matrix and tensor operations by BLAS. A three-dimensional particle in cell code is developed based on UPSF. Two test cases, Landau damping and Weibel instability for electrostatic and electromagnetic situation respectively, are presented to show the validation and performance of the UPSF code.

Correlative Fluorescence and Electron Microscopy

PubMed Central

Schirra, Randall T.; Zhang, Peijun

2014-01-01

Correlative fluorescence and electron microscopy (CFEM) is a multimodal technique that combines dynamic and localization information from fluorescence methods with ultrastructural data from electron microscopy, to give new information about how cellular components change relative to the spatiotemporal dynamics within their environment. In this review, we will discuss some of the basic techniques and tools of the trade for utilizing this attractive research method, which is becoming a very powerful tool for biology labs. The information obtained from correlative methods has proven to be invaluable in creating consensus between the two types of microscopy, extending the capability of each, and cutting the time and expense associate with using each method separately for comparative analysis. The realization of the advantages of these methods in cell biology have led to rapid improvement in the protocols and have ushered in a new generation of instruments to reach the next level of correlation – integration. PMID:25271959

Object segmentation using graph cuts and active contours in a pyramidal framework

NASA Astrophysics Data System (ADS)

Subudhi, Priyambada; Mukhopadhyay, Susanta

2018-03-01

Graph cuts and active contours are two very popular interactive object segmentation techniques in the field of computer vision and image processing. However, both these approaches have their own well-known limitations. Graph cut methods perform efficiently giving global optimal segmentation result for smaller images. However, for larger images, huge graphs need to be constructed which not only takes an unacceptable amount of memory but also increases the time required for segmentation to a great extent. On the other hand, in case of active contours, initial contour selection plays an important role in the accuracy of the segmentation. So a proper selection of initial contour may improve the complexity as well as the accuracy of the result. In this paper, we have tried to combine these two approaches to overcome their above-mentioned drawbacks and develop a fast technique of object segmentation. Here, we have used a pyramidal framework and applied the mincut/maxflow algorithm on the lowest resolution image with the least number of seed points possible which will be very fast due to the smaller size of the image. Then, the obtained segmentation contour is super-sampled and and worked as the initial contour for the next higher resolution image. As the initial contour is very close to the actual contour, so fewer number of iterations will be required for the convergence of the contour. The process is repeated for all the high-resolution images and experimental results show that our approach is faster as well as memory efficient as compare to both graph cut or active contour segmentation alone.

Cutting Force Predication Based on Integration of Symmetric Fuzzy Number and Finite Element Method

PubMed Central

Wang, Zhanli; Hu, Yanjuan; Wang, Yao; Dong, Chao; Pang, Zaixiang

2014-01-01

In the process of turning, pointing at the uncertain phenomenon of cutting which is caused by the disturbance of random factors, for determining the uncertain scope of cutting force, the integrated symmetric fuzzy number and the finite element method (FEM) are used in the prediction of cutting force. The method used symmetric fuzzy number to establish fuzzy function between cutting force and three factors and obtained the uncertain interval of cutting force by linear programming. At the same time, the change curve of cutting force with time was directly simulated by using thermal-mechanical coupling FEM; also the nonuniform stress field and temperature distribution of workpiece, tool, and chip under the action of thermal-mechanical coupling were simulated. The experimental result shows that the method is effective for the uncertain prediction of cutting force. PMID:24790556

The influence of alternative plant propagation and stand establishment techniques on survival and growth of eastern cottonwood (Populus deltoids Bartr.) clones

Treesearch

Donald J. Kaczmarek; Randall Rousseau; Jeff A. Wright; Brian Wachelka

2014-01-01

Four eastern cottonwood clones, including standard operational clone ST66 and three advanced clonal selections were produced and included in a test utilizing five different plant propagation methods. Despite relatively large first-year growth differences among clones, all clones demonstrated similar responses to the treatments and clone × cutting treatment interactions...

Optimising Regionalisation Techniques: Identifying Centres of Endemism in the Extraordinarily Endemic-Rich Cape Floristic Region

PubMed Central

Bradshaw, Peter L.; Colville, Jonathan F.; Linder, H. Peter

2015-01-01

We used a very large dataset (>40% of all species) from the endemic-rich Cape Floristic Region (CFR) to explore the impact of different weighting techniques, coefficients to calculate similarity among the cells, and clustering approaches on biogeographical regionalisation. The results were used to revise the biogeographical subdivision of the CFR. We show that weighted data (down-weighting widespread species), similarity calculated using Kulczinsky’s second measure, and clustering using UPGMA resulted in the optimal classification. This maximized the number of endemic species, the number of centres recognized, and operational geographic units assigned to centres of endemism (CoEs). We developed a dendrogram branch order cut-off (BOC) method to locate the optimal cut-off points on the dendrogram to define candidate clusters. Kulczinsky’s second measure dendrograms were combined using consensus, identifying areas of conflict which could be due to biotic element overlap or transitional areas. Post-clustering GIS manipulation substantially enhanced the endemic composition and geographic size of candidate CoEs. Although there was broad spatial congruence with previous phytogeographic studies, our techniques allowed for the recovery of additional phytogeographic detail not previously described for the CFR. PMID:26147438

Piezosurgery in head and neck oncological and reconstructive surgery: personal experience on 127 cases

PubMed Central

Crosetti, E; Battiston, B; Succo, G

2009-01-01

Summary Piezoelectric bone surgery, known simply as piezosurgery, is a new technique of osteotomy and osteoplasty, which requires the use of microvibrations of ultrasonic frequency scalpels. The principle of piezosurgery is ultrasonic transduction, obtained by piezoelectric ceramic contraction and expansion. The vibrations thus obtained are amplified and transferred onto the insert of a drill which, when rapidly applied, with slight pressure, upon the bony tissue, results, in the presence of irrigation with physiological solution, in the cavitation phenomenon, with a mechanical cutting effect, exclusively on mineralized tissues. Personal experience with the use of piezosurgery in head and neck oncological and reconstructive surgery is relatively recent, having been developed in 2002-2006, and, so far, involves 127 cases; preliminary results are interesting and improving in the, hopefully, developmental phases of inserts with specific geometrics on account of the characteristics of the various aspects of surgical ENT operations. Furthermore, with piezoelectric surgery it has been possible to perform precise osteotomy lines, micrometric and curvilinear with absolute confidence, particularly in close proximity to the vessels and nerves and other important facial structures (dura mater). There can be no doubt, since this is a new cutting method, that piezosurgery involves a different learning curve compared to other techniques, requiring obstacles of a psychological nature to be overcome as well as that concerning surgical expertise. Given the numbers of cases treated and the relative power of this instrument, analysis of complications, intra-operative time (which would appear, on average, to be 20% longer) and, therefore, morbility, shows interesting potentiality of the technique. This new ultrasound cutting method will, no doubt, in the future, be increasingly used in ENT surgery, particularly with improvements in power and geometry of the inserts, with possible applications also in neurosurgery, paediatric surgery and orthopedics, branches in which a selective action upon the mineralized tissues is of fundamental importance. PMID:19609375

Decoherence control mechanisms of a charged magneto-oscillator in contact with different environments

NASA Astrophysics Data System (ADS)

Rajesh, Asam; Bandyopadhyay, Malay; Jayannavar, Arun M.

2017-12-01

In this work, we consider two different techniques based on reservoir engineering process and quantum Zeno control method to analyze the decoherence control mechanism of a charged magneto-oscillator in contact with different type of environment. Our analysis reveals that both the control mechanisms are very much sensitive on the details of different environmental spectrum (J (ω)), and also on different system and reservoir parameters, e.g., external magnetic field (rc), confinement length (r0), temperature (T), cut-off frequency of reservoir spectrum (ωcut), and measurement interval (τ). We also demonstrate the manipulation scheme of the continuous passage from decay suppression to decay acceleration by tuning the above mentioned system or reservoir parameters, e.g., rc, r0, T and τ.

Improved Concrete Cutting and Excavation Capabilities for Crater Repair Phase 2

DTIC Science & Technology

2015-05-01

production rate and ease of execution. The current ADR techniques, tactics, and procedures (TTPs) indicate cutting of pavement around a small crater...demonstrations and evaluations were used to create the techniques, tactics, and procedures (TTPs) manual describing the processes and requirements of...was more difficult when dowels were present. In general, the OUA demonstration validated that the new materials, equipment, and procedures were

Combining the Cutting and Mulliken methods for primary repair of the bilateral cleft lip nose.

PubMed

Morovic, Carmen Gloria; Cutting, Court

2005-11-01

Since 1990, primary bilateral cleft nasal reconstruction has been focused on placing the lower lateral cartilages into normal anatomical position. Of the four major techniques in this class, the Cutting (i.e., retrograde) method and the Mulliken method have been most successful. The retrograde method makes no external nasal incisions, but requires either preoperative or postoperative nasal molding to achieve maximum benefit. Mulliken's technique does not require molding, but leaves the footplates of the medial crura in the depression above the projecting premaxilla associated with the diminutive anterior nasal spine. Leaving the footplates in place also prevents adequate approximation of the alar bases. In this article, the two methods are combined to achieve the benefits of both. We report our experience with the retrograde nasal approach associated with marginal rim incisions (Mulliken method) in a series of 25 consecutive bilateral cleft lip cases simultaneous with lip repair. We performed a retrograde approach through membranous septum incisions elevating a prolabial-columellar flap. To facilitate alar cartilage manipulation we added bilateral marginal rim incisions. Nasal width, columella length and width, tip projection, and nasolabial angle were analyzed after a minimum of 2 years after surgery. These were compared with a normal, age-matched, control group. We also examined nostril symmetry and marginal nostril scars. Columellar length was not statistically significantly different from that of the control group (p = 0.122442). Nasal width, columellar width, tip projection, and nasolabial angle were all significantly greater in the cleft group than normal (p < 0.001). No hypertrophied scars were found associated with the marginal rim scar. Adding the Mulliken approach allows alar cartilage manipulation to be performed more easily than when using the retrograde approach alone. Tip projection and alar base narrowing are facilitated using the combined technique rather than the Mulliken approach alone. Prolabial flap manipulation is safe using this combined approach, even in cases with a severely projected premaxilla. We believe that the combined approach is safe and yields better long-term results than either technique alone.

Redundant via insertion in self-aligned double patterning

NASA Astrophysics Data System (ADS)

Song, Youngsoo; Jung, Jinwook; Shin, Youngsoo

2017-03-01

Redundant via (RV) insertion is employed to enhance via manufacturability, and has been extensively studied. Self-aligned double patterning (SADP) process, brings a new challenge to RV insertion since newly created cut for each RV insertion has to be taken care of. Specifically, when a cut for RV, which we simply call RV-cut, is formed, cut conflict may occur with nearby line-end cuts, which results in a decrease in RV candidates. We introduce cut merging to reduce the number of cut conflicts; merged cuts are processed with stitch using litho-etch-litho-etch (LELE) multi-patterning method. In this paper, we propose a new RV insertion method with cut merging in SADP for the first time. In our experiments, a simple RV insertion yields 55.3% vias to receives RVs; our proposed method that considers cut merging increases that number to 69.6% on average of test circuits.

Round-off errors in cutting plane algorithms based on the revised simplex procedure

NASA Technical Reports Server (NTRS)

Moore, J. E.

1973-01-01

This report statistically analyzes computational round-off errors associated with the cutting plane approach to solving linear integer programming problems. Cutting plane methods require that the inverse of a sequence of matrices be computed. The problem basically reduces to one of minimizing round-off errors in the sequence of inverses. Two procedures for minimizing this problem are presented, and their influence on error accumulation is statistically analyzed. One procedure employs a very small tolerance factor to round computed values to zero. The other procedure is a numerical analysis technique for reinverting or improving the approximate inverse of a matrix. The results indicated that round-off accumulation can be effectively minimized by employing a tolerance factor which reflects the number of significant digits carried for each calculation and by applying the reinversion procedure once to each computed inverse. If 18 significant digits plus an exponent are carried for each variable during computations, then a tolerance value of 0.1 x 10 to the minus 12th power is reasonable.

Assessing resolution in live cell structured illumination microscopy

NASA Astrophysics Data System (ADS)

Pospíšil, Jakub; Fliegel, Karel; Klíma, Miloš

2017-12-01

Structured Illumination Microscopy (SIM) is a powerful super-resolution technique, which is able to enhance the resolution of optical microscope beyond the Abbe diffraction limit. In the last decade, numerous SIM methods that achieve the resolution of 100 nm in the lateral dimension have been developed. The SIM setups with new high-speed cameras and illumination pattern generators allow rapid acquisition of the live specimen. Therefore, SIM is widely used for investigation of the live structures in molecular and live cell biology. Quantitative evaluation of resolution enhancement in a real sample is essential to describe the efficiency of super-resolution microscopy technique. However, measuring the resolution of a live cell sample is a challenging task. Based on our experimental findings, the widely used Fourier ring correlation (FRC) method does not seem to be well suited for measuring the resolution of SIM live cell video sequences. Therefore, the resolution assessing methods based on Fourier spectrum analysis are often used. We introduce a measure based on circular average power spectral density (PSDca) estimated from a single SIM image (one video frame). PSDca describes the distribution of the power of a signal with respect to its spatial frequency. Spatial resolution corresponds to the cut-off frequency in Fourier space. In order to estimate the cut-off frequency from a noisy signal, we use a spectral subtraction method for noise suppression. In the future, this resolution assessment approach might prove useful also for single-molecule localization microscopy (SMLM) live cell imaging.

Split-shot sinker facilitates seton treatment of anal fistulae.

PubMed

Awad, M L; Sell, H W; Stahlfeld, K R

2009-06-01

The cutting seton is an inexpensive and effective method of treating high complex perianal fistulae. Following placement of the seton, advancement through the external sphincter muscles requires progressive tightening of the seton. The requirement for maintaining the appropriate tension and onset of perianal pressure necrosis are problems frequently encountered using this technique. Using a 3-0 polypropylene suture, a red-rubber catheter, and a nontoxic tin split-shot sinker, we minimized or eliminated these problems. We initially used this technique in one patient with satisfactory results. This technique is technically easy, safe, inexpensive, and efficient, and we are using it in all patients with high perianal fistulae who require a seton.

Real-time haptic cutting of high-resolution soft tissues.

PubMed

Wu, Jun; Westermann, Rüdiger; Dick, Christian

2014-01-01

We present our systematic efforts in advancing the computational performance of physically accurate soft tissue cutting simulation, which is at the core of surgery simulators in general. We demonstrate a real-time performance of 15 simulation frames per second for haptic soft tissue cutting of a deformable body at an effective resolution of 170,000 finite elements. This is achieved by the following innovative components: (1) a linked octree discretization of the deformable body, which allows for fast and robust topological modifications of the simulation domain, (2) a composite finite element formulation, which thoroughly reduces the number of simulation degrees of freedom and thus enables to carefully balance simulation performance and accuracy, (3) a highly efficient geometric multigrid solver for solving the linear systems of equations arising from implicit time integration, (4) an efficient collision detection algorithm that effectively exploits the composition structure, and (5) a stable haptic rendering algorithm for computing the feedback forces. Considering that our method increases the finite element resolution for physically accurate real-time soft tissue cutting simulation by an order of magnitude, our technique has a high potential to significantly advance the realism of surgery simulators.

A review of virtual cutting methods and technology in deformable objects.

PubMed

Wang, Monan; Ma, Yuzheng

2018-06-05

Virtual cutting of deformable objects has been a research topic for more than a decade and has been used in many areas, especially in surgery simulation. We refer to the relevant literature and briefly describe the related research. The virtual cutting method is introduced, and we discuss the benefits and limitations of these methods and explore possible research directions. Virtual cutting is a category of object deformation. It needs to represent the deformation of models in real time as accurately, robustly and efficiently as possible. To accurately represent models, the method must be able to: (1) model objects with different material properties; (2) handle collision detection and collision response; and (3) update the geometry and topology of the deformable model that is caused by cutting. Virtual cutting is widely used in surgery simulation, and research of the cutting method is important to the development of surgery simulation. Copyright © 2018 John Wiley & Sons, Ltd.

A new method for the prediction of chatter stability lobes based on dynamic cutting force simulation model and support vector machine

NASA Astrophysics Data System (ADS)

Peng, Chong; Wang, Lun; Liao, T. Warren

2015-10-01

Currently, chatter has become the critical factor in hindering machining quality and productivity in machining processes. To avoid cutting chatter, a new method based on dynamic cutting force simulation model and support vector machine (SVM) is presented for the prediction of chatter stability lobes. The cutting force is selected as the monitoring signal, and the wavelet energy entropy theory is used to extract the feature vectors. A support vector machine is constructed using the MATLAB LIBSVM toolbox for pattern classification based on the feature vectors derived from the experimental cutting data. Then combining with the dynamic cutting force simulation model, the stability lobes diagram (SLD) can be estimated. Finally, the predicted results are compared with existing methods such as zero-order analytical (ZOA) and semi-discretization (SD) method as well as actual cutting experimental results to confirm the validity of this new method.

Automatic Dissection Of Plantlets

NASA Astrophysics Data System (ADS)

Batchelor, B. G.; Harris, I. P.; Marchant, J. A.; Tillett, R. D.

1989-03-01

Micropropagation is a technique used in horticulture for generating a monoclonal colony of plants. A tiny plantlet is cut into several parts, each of which is then replanted. At the moment, the cutting is performed manually. Automating this task would have significant economic benefits. A robot designed to dissect plants would need to be equipped with intelligent visual sensing. This article is concerned with the image acquisition and processing techniques which such a machine might use. A program, which can calculate where to cut a plant with an "open" structure, is presented. This is expressed in the ProVision language, which is described in another article presented at this conference. (Article 1002-65)

Thin edge-defined film-fed growth (EFG) octagons

NASA Astrophysics Data System (ADS)

Kalejs, J. P.

1992-03-01

Mobil Solar Energy Corp. investigated manufacturing crystalline silicon wafers using the edge-defined film-fed growth (EFG) technique. This report identifies the following: (1) current capabilities for manufacturing 200-micron-thick crystalline silicon wafers (10 cm x 10 cm) produced by growing octagons using the EFG technique and laser cutting them into wafers; (2) potential manufacturing improvements from decreasing the thickness of the wafers, improving the quality of the laser cut edge, and increasing cutting speed, all of which lead to reduce manufacturing costs, improved performance, and increased production capacities; (3) problems that impede achieving these potentials; and (4) costs and other requirements involved in overcoming the problems.

Comparative Evaluation of Cutting Methods of Activated Concrete from Nuclear Power Plant Decommissioning - 13548

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, HakSoo; Chung, SungHwan; Maeng, SungJun

2013-07-01

The amount of radioactive wastes from decommissioning of a nuclear power plant varies greatly depending on factors such as type and size of the plant, operation history, decommissioning options, and waste treatment and volume reduction methods. There are many methods to decrease the amount of decommissioning radioactive wastes including minimization of waste generation, waste reclassification through decontamination and cutting methods to remove the contaminated areas. According to OECD/NEA, it is known that the radioactive waste treatment and disposal cost accounts for about 40 percentage of the total decommissioning cost. In Korea, it is needed to reduce amount of decommissioning radioactivemore » waste due to high disposal cost, about $7,000 (as of 2010) per a 200 liter drum for the low- and intermediate-level radioactive waste (LILW). In this paper, cutting methods to minimize the radioactive waste of activated concrete were investigated and associated decommissioning cost impact was assessed. The cutting methods considered are cylindrical and volume reductive cuttings. The study showed that the volume reductive cutting is more cost-effective than the cylindrical cutting. Therefore, the volume reductive cutting method can be effectively applied to the activated bio-shield concrete. (authors)« less

CO2 laser cutting of ultra thin (75 μm) glass based rigid optical solar reflector (OSR) for spacecraft application

NASA Astrophysics Data System (ADS)

Mishra, Shubham; Sridhara, N.; Mitra, Avijit; Yougandar, B.; Dash, Sarat Kumar; Agarwal, Sanjay; Dey, Arjun

2017-03-01

Present study reports for the first time laser cutting of multilayered coatings on both side of ultra thin (i.e., 75 μm) glass substrate based rigid optical solar reflector (OSR) for spacecraft thermal control application. The optimization of cutting parameters was carried out as a function of laser power, cutting speed and number of cutting passes and their effect on cutting edge quality. Systematic and in-detail microstructural characterizations were carried out by optical and scanning electron microscopy techniques to study the laser affected zone and cutting edge quality. Sheet resistance and water contact angle experiments were also conducted locally both prior and after laser cut to investigate the changes of electrical and surface properties, if any.

Energy minimization in medical image analysis: Methodologies and applications.

PubMed

Zhao, Feng; Xie, Xianghua

2016-02-01

Energy minimization is of particular interest in medical image analysis. In the past two decades, a variety of optimization schemes have been developed. In this paper, we present a comprehensive survey of the state-of-the-art optimization approaches. These algorithms are mainly classified into two categories: continuous method and discrete method. The former includes Newton-Raphson method, gradient descent method, conjugate gradient method, proximal gradient method, coordinate descent method, and genetic algorithm-based method, while the latter covers graph cuts method, belief propagation method, tree-reweighted message passing method, linear programming method, maximum margin learning method, simulated annealing method, and iterated conditional modes method. We also discuss the minimal surface method, primal-dual method, and the multi-objective optimization method. In addition, we review several comparative studies that evaluate the performance of different minimization techniques in terms of accuracy, efficiency, or complexity. These optimization techniques are widely used in many medical applications, for example, image segmentation, registration, reconstruction, motion tracking, and compressed sensing. We thus give an overview on those applications as well. Copyright © 2015 John Wiley & Sons, Ltd.

Impact of the On the Cutting Edge Professional Development Program on U.S. Geoscience Faculty

NASA Astrophysics Data System (ADS)

Manduca, C. A.; Iverson, E. A.; Czujko, R.; Macdonald, H.; Mogk, D. W.; Tewksbury, B. J.; McLaughlin, J.; Sanford, C.; Greenseid, L.; Luxenberg, M.

2011-12-01

Transforming STEM education from a dominantly lecture-based format focused on facts to classrooms where students engage with the process of understanding the world through science is a primary goal of faculty development. On the Cutting Edge seeks to support this transformation by using workshops and a website to build a community of geoscience faculty who learn from one another. In order to assess the impact of the On the Cutting Edge program, we surveyed 5917 U.S. geoscience faculty in 2009 and received 2874 completed responses (49% response rate). We looked at the differences in responses between workshop participants who also use the website, website users who have not attended a Cutting Edge workshop, and survey respondents who had neither attended a Cutting Edge workshop nor used the Cutting Edge website. The number of respondents who had attended a Cutting Edge workshop and had not used the website was too small to analyze. Courses described by Cutting Edge workshop participants make significantly less use of lecture and more use of small group discussion and in-class activities. While all faculty respondents routinely update their courses, workshop participants are more likely to have changed their teaching methods in the two years leading up to the survey. When making changes to their teaching methods, workshop participants are more likely than other populations to seek information about teaching on the web, consult journal articles about teaching, and seek advice from colleagues outside their department and from nationally known leaders in geoscience education. Workshop participants are also more likely to tell a colleague when they do something that is particularly successful in class. End-of-workshop survey and follow-up interview data indicate that participants leave workshops reinvigorated, with a new or renewed commitment to student-centered teaching, and that they make use of the website as they implement ideas for changing their teaching following the workshop. Participants can identify specific ideas, techniques, and materials from workshops and the website that they have used in their teaching, and they attribute substantial improvements in their teaching to the Cutting Edge professional development experience. While the differences in behavior reported in the survey results may in part reflect the choice to attend workshops by faculty inclined to improve their teaching, the combination of motivation, attitude, and information developed through the workshop experience is amplifying this effect.

Mitigation of environmental impacts due to ghat road formation in Palamalai Hills, South India, by optimizing cut and fill volumes using GPS and GIS techniques.

PubMed

Arulmozhi, R; Subramani, T; Sukumar, S

2015-01-01

Formation of new roads generally brings about adverse impact on the environment, and in the case of hill roads, the impact is diverse and effective measures are required to mitigate it. The common problems in hill road formation are tree cutting, destruction of canopies, change in land use pattern, soil erosion, slope instability, induced landslides, invasion of foreign species, and so on. Removal of trees and vegetations causes rapid soil erosion, landslides, and invasion of foreign species posing danger to the survival of weak native species. Dumping of surplus earth materials on the valley side poses a significant threat to the environment as it would cause induced landslides. Using the cut earth for filling in road formation and dumping, the surplus cut earth in safe locations will reduce environmental degradation considerably. Conventionally, hill road alignments are finalized using traditional survey methods using ghat tracer, compass, and leveling surveys which require enormous complicated field and office works. Any revision to reduce the quantum of earthwork is difficult in this method due to its complex nature. In the present study at Palamalai Hills, South India, an alignment for a length of 7.95 km was prepared by traditional methods using ghat tracer and total station instruments for survey works. The earthwork quantities were ascertained from the longitudinal profile of the alignment. A GPS survey was also conducted along the alignment to examine its utility in alignment modification. To modify the stretches, where the earthwork cutting and filling are above normal and unbalanced and result in surplus earth, repeated GPS surveys were conducted along different paths to optimize the earthwork. The earthwork quantities of the original alignment were analyzed, and its correlation with environmental effect and the usefulness of the GPS survey in this task are presented in this paper.

A safer method for body restoration following autopsy.

PubMed

Duflou, Johan; McNamara, Bradley; Cluney, Robert

2014-01-01

Restoration of autopsy incisions can result in inadvertent needle stick injury to the prosector, which can be difficult to prevent even with the use of personal protective equipment such as Kevlar cut resistant gloves. We present a new technique for closure of autopsy incisions using a commonly available commercial hardware tool, a hole punch with a lever enhanced action, combined with blunt probe sewing, which results in an esthetic and leak-proof means of restoring cadavers. This technique is especially useful in cases which may pose blood-borne infection risks to the prosector. © 2013 American Academy of Forensic Sciences.

Computer-aided design and computer-aided manufacturing cutting guides and customized titanium plates are useful in upper maxilla waferless repositioning.

PubMed

Mazzoni, Simona; Bianchi, Alberto; Schiariti, Giulio; Badiali, Giovanni; Marchetti, Claudio

2015-04-01

The purpose of the present study was to develop a computer-aided design (CAD) and computer-aided manufacturing (CAM) technique that enabled fabrication of surgical cutting guides and titanium fixation plates that would allow the upper maxilla to be repositioned correctly without a surgical splint in orthognathic patients. Ten patients were recruited. A complete CAD-CAM workflow for orthognathic surgery has 3 steps: 1) virtual planning of the surgical treatment, 2) CAD-CAM and 3-dimensional printing of customized surgical devices (surgical cutting guide and titanium fixation plates), and 3) computer-aided surgery. Upper maxilla repositioning was performed in a waferless manner using a CAD-CAM device: the surgical cutting guide was used during surgery to pilot the osteotomy line that had been planned preoperatively at the computer and the custom-made fixation titanium plates allowed desired repositioning of the maxilla. To evaluate the reproducibility of this CAD-CAM orthognathic surgical method, the virtually planned and actually achieved positions of the upper maxilla were compared. Overlap errors using a threshold value smaller than 2 mm were evaluated, and the frequency of such errors was used as a measurement of accuracy. By this definition, the accuracy was 100% in 7 patients (range in all patients, 62 to 100%; median, 92.7%). These results tend to confirm that the use of CAD-CAM cutting guides and customized titanium plates for upper maxilla repositioning represents a promising method for the accurate reproduction of preoperative virtual planning without the use of surgical splints. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Measuring Concentrations of Dissolved Methane and Ethane and the 13 C of Methane in Shale and Till.

PubMed

Hendry, M Jim; Barbour, S Lee; Schmeling, Erin E; Mundle, Scott O C

2017-01-01

Baseline characterization of concentrations and isotopic values of dissolved natural gases is needed to identify contamination caused by the leakage of fugitive gases from oil and gas activities. Methods to collect and analyze baseline concentration-depth profiles of dissolved CH 4 and C 2 H 6 and δ 13 C-CH 4 in shales and Quaternary clayey tills were assessed at two sites in the Williston Basin, Canada. Core and cuttings samples were stored in Isojars ® in a low O 2 headspace prior to analysis. Measurements and multiphase diffusion modeling show that the gas concentrations in core samples yield well-defined and reproducible depth profiles after 31-d equilibration. No measurable oxidative loss or production during core sample storage was observed. Concentrations from cuttings and mud gas logging (including IsoTubes ® ) were much lower than from cores, but correlated well. Simulations suggest the lower concentrations from cuttings can be attributed to drilling time, and therefore their use to define gas concentration profiles may have inherent limitations. Calculations based on mud gas logging show the method can provide estimates of core concentrations if operational parameters for the mud gas capture cylinder are quantified. The δ 13 C-CH 4 measured from mud gas, IsoTubes ® , cuttings, and core samples are consistent, exhibiting slight variations that should not alter the implications of the results in identifying the sources of the gases. This study shows core and mud gas techniques and, to a lesser extent, cuttings, can generate high-resolution depth profiles of dissolved hydrocarbon gas concentrations and their isotopes. © 2016, National Ground Water Association.

26 CFR 1.669(a)-4 - Tax attributable to short-cut throwback method.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 8 2011-04-01 2011-04-01 false Tax attributable to short-cut throwback method... Applicable to Taxable Years Beginning Before January 1, 1969 § 1.669(a)-4 Tax attributable to short-cut... the tax on the amounts deemed distributed under section 666 by the short-cut throwback method provided...

New method of paired thyrotropin assay as a screening test for neonatal hypothyroidism. [/sup 125/I tracer technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyai, K.; Oura, T.; Kawashima, M.

1978-11-01

A simple and reliable method of paired TSH assay was developed and used in screening for neonatal primary hypothyroidism. In this method, a paired assay is first done. Equal parts of the extracts of dried blood spots on filter paper (9 mm diameter) from two infants 4 to 7 days old are combined and assayed for TSH by double antibody RIA. If the value obtained is over the cut-off point, the extracts are assayed separately for TSH in a second assay to identify the abnormal sample. Two systems, A and B, with different cut-off points were tested. On the basismore » of reference blood samples (serum levels of TSH, 80 ..mu..U/ml in system A and 40 ..mu..U/ml in system B), the cut-off point was selected as follows: upper 5 (A) or 4 (B) percentile in the paired assay and values of reference blood samples in the second individual assay. Four cases (2 in A and 2 in B) of neonatal primary hypothyroidism were found among 25 infants (23 in A and 2 in B) who were recalled from a general population of 41,400 infants (24,200 in A and 17,200 in B) by 22,700 assays. This paired TSH assay system saves labor and expense for screening neonatal hypothyroidism.« less

Laser capture microdissection: Arcturus(XT) infrared capture and UV cutting methods.

PubMed

Gallagher, Rosa I; Blakely, Steven R; Liotta, Lance A; Espina, Virginia

2012-01-01

Laser capture microdissection (LCM) is a technique that allows the precise procurement of enriched cell populations from a heterogeneous tissue under direct microscopic visualization. LCM can be used to harvest the cells of interest directly or can be used to isolate specific cells by ablating the unwanted cells, resulting in histologically enriched cell populations. The fundamental components of laser microdissection technology are (a) visualization of the cells of interest via microscopy, (b) transfer of laser energy to a thermolabile polymer with either the formation of a polymer-cell composite (capture method) or transfer of laser energy via an ultraviolet laser to photovolatize a region of tissue (cutting method), and (c) removal of cells of interest from the heterogeneous tissue section. Laser energy supplied by LCM instruments can be infrared (810 nm) or ultraviolet (355 nm). Infrared lasers melt thermolabile polymers for cell capture, whereas ultraviolet lasers ablate cells for either removal of unwanted cells or excision of a defined area of cells. LCM technology is applicable to an array of applications including mass spectrometry, DNA genotyping and loss-of-heterozygosity analysis, RNA transcript profiling, cDNA library generation, proteomics discovery, and signal kinase pathway profiling. This chapter describes the unique features of the Arcturus(XT) laser capture microdissection instrument, which incorporates both infrared capture and ultraviolet cutting technology in one instrument, using a proteomic downstream assay as a model.

A Fast, Reliable, and Sensitive Method for Detection and Quantification of Listeria monocytogenes and Escherichia coli O157:H7 in Ready-to-Eat Fresh-Cut Products by MPN-qPCR

PubMed Central

Russo, Pasquale; Botticella, Giuseppe; Capozzi, Vittorio; Massa, Salvatore; Spano, Giuseppe; Beneduce, Luciano

2014-01-01

In the present work we developed a MPN quantitative real-time PCR (MPN-qPCR) method for a fast and reliable detection and quantification of Listeria monocytogenes and Escherichia coli O157:H7 in minimally processed vegetables. In order to validate the proposed technique, the results were compared with conventional MPN followed by phenotypic and biochemical assays methods. When L. monocytogenes and E. coli O157:H7 were artificially inoculated in fresh-cut vegetables, a concentration as low as 1 CFU g−1 could be detected in 48 hours for both pathogens. qPCR alone allowed a limit of detection of 101 CFU g−1 after 2 hours of enrichment for L. monocytogenes and E. coli O157:H7. Since minimally processed ready-to-eat vegetables are characterized by very short shelf life, our method can potentially address the consistent reduction of time for microbial analysis, allowing a better management of quality control. Moreover, the occurrences of both pathogenic bacteria in mixed salad samples and fresh-cut melons were monitored in two production plants from the receipt of the raw materials to the early stages of shelf life. No sample was found to be contaminated by L. monocytogenes. One sample of raw mixed salad was found positive to an H7 enterohemorrhagic serotype. PMID:24949460

Detection of Salmonella sp in chicken cuts using immunomagnetic separation

PubMed Central

de Cássia dos Santos da Conceição, Rita; Moreira, Ângela Nunes; Ramos, Roberta Juliano; Goularte, Fabiana Lemos; Carvalhal, José Beiro; Aleixo, José Antonio Guimarães

2008-01-01

The immunomagnetic separation (IMS) is a technique that has been used to increase sensitivity and specificity and to decrease the time required for detection of Salmonella in foods through different methodologies. In this work we report on the development of a method for detection of Salmonella in chicken cuts using in house antibody-sensitized microspheres associated to conventional plating in selective agar (IMS-plating). First, protein A-coated microspheres were sensitized with polyclonal antibodies against lipopolysacharide and flagella from salmonellae and used to standardize a procedure for capturing Salmonella Enteritidis from pure cultures and detection in selective agar. Subsequently, samples of chicken meat experimentally contaminated with S. Enteritidis were analyzed immediately after contamination and after 24h of refrigeration using three enrichment protocols. The detection limit of the IMS-plating procedure after standardization with pure culture was about 2x10 CFU/mL. The protocol using non-selective enrichment for 6-8h, selective enrichment for 16-18h and a post-enrichment for 4h gave the best results of S. Enteritidis detection by IMS-plating in experimentally contaminated meat. IMS-plating using this protocol was compared to the standard culture method for salmonellae detection in naturally contaminated chicken cuts and yielded 100% sensitivity and 94% specificity. The method developed using in house prepared magnetic microespheres for IMS and plating in selective agar was able to diminish by at least one day the time required for detection of Salmonella in chicken products by the conventional culture method. PMID:24031199

Feasibility of Tactical Air Delivery Resupply Using Gliders

DTIC Science & Technology

2016-12-01

using modern design and manufacturing techniques including AutoCAD, 3D printing , laser cutting and CorelDraw, and conducting field testing and...Sparrow,” using modern design and manufacturing techniques including AutoCAD, 3D printing , laser cutting and CorelDraw, and conducting field testing and...the desired point(s) of impact due to the atmospheric three-dimensional ( 3D ) wind and density field encountered by the descending load under canopy

A Review of Computational Methods for Finding Non-Coding RNA Genes

PubMed Central

Abbas, Qaisar; Raza, Syed Mansoor; Biyabani, Azizuddin Ahmed; Jaffar, Muhammad Arfan

2016-01-01

Finding non-coding RNA (ncRNA) genes has emerged over the past few years as a cutting-edge trend in bioinformatics. There are numerous computational intelligence (CI) challenges in the annotation and interpretation of ncRNAs because it requires a domain-related expert knowledge in CI techniques. Moreover, there are many classes predicted yet not experimentally verified by researchers. Recently, researchers have applied many CI methods to predict the classes of ncRNAs. However, the diverse CI approaches lack a definitive classification framework to take advantage of past studies. A few review papers have attempted to summarize CI approaches, but focused on the particular methodological viewpoints. Accordingly, in this article, we summarize in greater detail than previously available, the CI techniques for finding ncRNAs genes. We differentiate from the existing bodies of research and discuss concisely the technical merits of various techniques. Lastly, we review the limitations of ncRNA gene-finding CI methods with a point-of-view towards the development of new computational tools. PMID:27918472

Detection of fallen trees in ALS point clouds using a Normalized Cut approach trained by simulation

NASA Astrophysics Data System (ADS)

Polewski, Przemyslaw; Yao, Wei; Heurich, Marco; Krzystek, Peter; Stilla, Uwe

2015-07-01

Downed dead wood is regarded as an important part of forest ecosystems from an ecological perspective, which drives the need for investigating its spatial distribution. Based on several studies, Airborne Laser Scanning (ALS) has proven to be a valuable remote sensing technique for obtaining such information. This paper describes a unified approach to the detection of fallen trees from ALS point clouds based on merging short segments into whole stems using the Normalized Cut algorithm. We introduce a new method of defining the segment similarity function for the clustering procedure, where the attribute weights are learned from labeled data. Based on a relationship between Normalized Cut's similarity function and a class of regression models, we show how to learn the similarity function by training a classifier. Furthermore, we propose using an appearance-based stopping criterion for the graph cut algorithm as an alternative to the standard Normalized Cut threshold approach. We set up a virtual fallen tree generation scheme to simulate complex forest scenarios with multiple overlapping fallen stems. This simulated data is then used as a basis to learn both the similarity function and the stopping criterion for Normalized Cut. We evaluate our approach on 5 plots from the strictly protected mixed mountain forest within the Bavarian Forest National Park using reference data obtained via a manual field inventory. The experimental results show that our method is able to detect up to 90% of fallen stems in plots having 30-40% overstory cover with a correctness exceeding 80%, even in quite complex forest scenes. Moreover, the performance for feature weights trained on simulated data is competitive with the case when the weights are calculated using a grid search on the test data, which indicates that the learned similarity function and stopping criterion can generalize well on new plots.

X-radiography of trace fossils in limestones and dolostones from the Jurassic Smackover Formation, south Alabama

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esposito, R.A.; Castleman, S.P.; King, D.T. Jr.

X-radiography has been useful in studying biogenic sedimentary structures in unconsolidated sediments but the technique has not been applied often to the study of hard carbonate rock. The authors have applied x-radiography to the study of the lower part of the Smackover to enhance the complete petrologic description of the rock. The lower Smackover has many dense micrite intervals and intervals of monotonous, thin graded beds. Parts of the lower Smackover is also dolomitized. None of the above rocks contains significant amount of skeletal debris and trace fossils are not generally obvious in an etched slab of core. In limestone,more » they have detected well-preserved trace fossils by x-radiography, however. The dolostones show no traces using our method. In limestones, the traces are marked by minute amounts of finely divided iron sulfides. This causes a slight density difference resulting in greater x-ray absorption. They recognize two main trace-fossil types: a Thalassinoides best seen in slabs cut parallel to bedding and a Zoophycos best seen in slabs cut perpendicular to bedding. The technique requires a slab cut 8 mm thick with parallel flat surfaces and a medical x-ray unit using accelerating voltages of 66 kV and 10 mas. Traces are most successfully imaged on industrial-quality films.« less

Specification Improvement Through Analysis of Proof Structure (SITAPS): High Assurance Software Development

DTIC Science & Technology

2016-02-01

proof in mathematics. For example, consider the proof of the Pythagorean Theorem illustrated at: http://www.cut-the-knot.org/ pythagoras / where 112...methods and tools have made significant progress in their ability to model software designs and prove correctness theorems about the systems modeled...assumption criticality” or “ theorem root set size” SITAPS detects potentially brittle verification cases. SITAPS provides tools and techniques that

Brainstorm: A User-Friendly Application for MEG/EEG Analysis

PubMed Central

Tadel, François; Baillet, Sylvain; Mosher, John C.; Pantazis, Dimitrios; Leahy, Richard M.

2011-01-01

Brainstorm is a collaborative open-source application dedicated to magnetoencephalography (MEG) and electroencephalography (EEG) data visualization and processing, with an emphasis on cortical source estimation techniques and their integration with anatomical magnetic resonance imaging (MRI) data. The primary objective of the software is to connect MEG/EEG neuroscience investigators with both the best-established and cutting-edge methods through a simple and intuitive graphical user interface (GUI). PMID:21584256

Characterization of Residual Stress Effects on Fatigue Crack Growth of a Friction Stir Welded Aluminum Alloy

NASA Technical Reports Server (NTRS)

Newman, John A.; Smith, Stephen W.; Seshadri, Banavara R.; James, Mark A.; Brazill, Richard L.; Schultz, Robert W.; Donald, J. Keith; Blair, Amy

2015-01-01

An on-line compliance-based method to account for residual stress effects in stress-intensity factor and fatigue crack growth property determinations has been evaluated. Residual stress intensity factor results determined from specimens containing friction stir weld induced residual stresses are presented, and the on-line method results were found to be in excellent agreement with residual stress-intensity factor data obtained using the cut compliance method. Variable stress-intensity factor tests were designed to demonstrate that a simple superposition model, summing the applied stress-intensity factor with the residual stress-intensity factor, can be used to determine the total crack-tip stress-intensity factor. Finite element, VCCT (virtual crack closure technique), and J-integral analysis methods have been used to characterize weld-induced residual stress using thermal expansion/contraction in the form of an equivalent delta T (change in local temperature during welding) to simulate the welding process. This equivalent delta T was established and applied to analyze different specimen configurations to predict residual stress distributions and associated residual stress-intensity factor values. The predictions were found to agree well with experimental results obtained using the crack- and cut-compliance methods.

Shielded Metal Arc Welding and Carbon Arc Cutting--Air. Teacher Edition [and] Student Edition [and] Student Workbook. Third Edition.

ERIC Educational Resources Information Center

Harper, Eddie; Knapp, John

This document contains the teacher and student texts and student workbook for a secondary-level course in shielded metal arc welding (SMAW) and carbon arc cutting that consists of units on the following topics: SMAW safety; SMAW equipment, applications, and techniques; hardfacing; and carbon arc cutting--air. The teacher edition includes the…

Application of plant growth regulators, a simple technique for improving the establishment success of plant cuttings in coastal dune restoration

NASA Astrophysics Data System (ADS)

Balestri, Elena; Vallerini, Flavia; Castelli, Alberto; Lardicci, Claudio

2012-03-01

Exogenous application of plant growth regulators (PGRs) may be an effective technique for increasing the rooting ability and the growth of vegetative fragments (cuttings) of plants used in dune restoration programs. Various concentrations (0, 50 and 100 mg l-1) of two auxins, alpha-naphtaleneacetic acid (NAA) and indole-3-butyric acid (IBA), and two cytokinins, 6-furfurylaminopurine (Kinetin) and 6-benzylaminopurine (BAP), were applied separately to cuttings of two widely used species for restoration, Ammophila arenaria and Sporobuls virginicus. Root development and production of new buds in cuttings were examined under laboratory conditions one month after application. Cuttings were also examined one year after transplanting into a sandy substratum under natural conditions, to test for possible long term effects of PGRs on plant establishment success and growth. The response of the two study species to PGRs differed substantially. In A. arenaria the auxin NAA at 100 mg l-1 reduced the time for root initiation and increased the rooting capacity of cuttings, while the cytokinin Kinetin at 50 mg l-1 facilitated root growth. No auxin had effect on rooting or growth of S. virginicus cuttings, but treatment with 100 mg l-1 Kinetin resulted in higher rooting success than the control. One year after planting, the cuttings of A. arenaria treated with 100 mg l-1 NAA showed a higher establishment success (90% vs. 55%) and produced more culms and longer roots than the control; those treated with cytokinins did not differ in the establishment success from the control, but had longer roots, more culms and rhizomes. On the other hand, the cuttings of S. virginicus treated with 100 mg l-1 Kinetin showed a higher establishment success (75% vs. 35%) and had more culms than the control. Therefore, in restoration activities that involved A. arenaria, a pre-treatment of cuttings with NAA would be beneficial, as it allows the production of a higher number of well-developed plants with high survival potential and greater area cover. In contrast, a pre-treatment of cuttings of S. virginicus with Kinetin would achieve more acceptable plant survival rates. This easy and low cost-effective technique may be extended to other dune plant species and applied on a large scale to improve the chance of dune restoration success.

Multi-loop Integrand Reduction with Computational Algebraic Geometry

NASA Astrophysics Data System (ADS)

Badger, Simon; Frellesvig, Hjalte; Zhang, Yang

2014-06-01

We discuss recent progress in multi-loop integrand reduction methods. Motivated by the possibility of an automated construction of multi-loop amplitudes via generalized unitarity cuts we describe a procedure to obtain a general parameterisation of any multi-loop integrand in a renormalizable gauge theory. The method relies on computational algebraic geometry techniques such as Gröbner bases and primary decomposition of ideals. We present some results for two and three loop amplitudes obtained with the help of the MACAULAY2 computer algebra system and the Mathematica package BASISDET.

INTERIOR VIEW SHOWING PROTOTYPE BEGUN APRIL 1988 METHOD OF CUTTING ...

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

INTERIOR VIEW SHOWING PROTOTYPE BEGUN APRIL 1988 METHOD OF CUTTING GLASS, "PERFECT TIN? MACHINE." MANUFACTURED IN DALLAS, TEXAS AND USED FOR CUTTING GLASS WITH A FINISHED EDGE. - Chambers-McKee Window Glass Company, Cutting House, Clay Avenue Extension, Jeannette, Westmoreland County, PA

Proximate and fatty acid composition and cholesterol content of different cuts of guinea fowl meat as affected by cooking method.

PubMed

Hoffman, Louwrens C; Tlhong, Tumelo M

2012-10-01

Poultry is one of the leading meat products in South Africa, and its nutritional composition can be affected by the cut and cooking method. Limited food composition data are available for typical South African poultry products. This study investigated the effect of different cuts and cooking methods on the proximate and fatty acid composition as well as the cholesterol content of guinea fowl (Numida meleagris) meat. The open-roasting method produced the highest moisture content for all cuts, and the baking bag method the lowest. The baking bag method resulted in the highest protein content. Cooking method had no effect on fat content, although breast had the lowest and thigh the highest fat content. Ash content was highest in the open-roasted drumstick. All cuts, regardless of cooking method, had a favourable polyunsaturated/saturated fatty acid (P/S) ratio (>0.4). Their n-6/n-3 ratio was also within the recommended beneficial range (<4:1). Both cooking method and cut affected cholesterol content. Different cuts of guinea fowl vary in proximate and fatty acid composition as well as in cholesterol content, which in turn is affected to varying degrees by cooking method. Copyright © 2012 Society of Chemical Industry.

Measurement and interpretation of skin prick test results.

PubMed

van der Valk, J P M; Gerth van Wijk, R; Hoorn, E; Groenendijk, L; Groenendijk, I M; de Jong, N W

2015-01-01

There are several methods to read skin prick test results in type-I allergy testing. A commonly used method is to characterize the wheal size by its 'average diameter'. A more accurate method is to scan the area of the wheal to calculate the actual size. In both methods, skin prick test (SPT) results can be corrected for histamine-sensitivity of the skin by dividing the results of the allergic reaction by the histamine control. The objectives of this study are to compare different techniques of quantifying SPT results, to determine a cut-off value for a positive SPT for histamine equivalent prick -index (HEP) area, and to study the accuracy of predicting cashew nut reactions in double-blind placebo-controlled food challenge (DBPCFC) tests with the different SPT methods. Data of 172 children with cashew nut sensitisation were used for the analysis. All patients underwent a DBPCFC with cashew nut. Per patient, the average diameter and scanned area of the wheal size were recorded. In addition, the same data for the histamine-induced wheal were collected for each patient. The accuracy in predicting the outcome of the DBPCFC using four different SPT readings (i.e. average diameter, area, HEP-index diameter, HEP-index area) were compared in a Receiver-Operating Characteristic (ROC) plot. Characterizing the wheal size by the average diameter method is inaccurate compared to scanning method. A wheal average diameter of 3 mm is generally considered as a positive SPT cut-off value and an equivalent HEP-index area cut-off value of 0.4 was calculated. The four SPT methods yielded a comparable area under the curve (AUC) of 0.84, 0.85, 0.83 and 0.83, respectively. The four methods showed comparable accuracy in predicting cashew nut reactions in a DBPCFC. The 'scanned area method' is theoretically more accurate in determining the wheal area than the 'average diameter method' and is recommended in academic research. A HEP-index area of 0.4 is determined as cut-off value for a positive SPT. However, in clinical practice, the 'average diameter method' is also useful, because this method provides similar accuracy in predicting cashew nut allergic reactions in the DBPCFC. Trial number NTR3572.

Mist Propagation of Juvenile Oak Cuttings

Treesearch

R. E. Farmer

1965-01-01

Greenwood apical cuttings from 1- to 4-month-old cherrybark oak (Quercus falcata var. pagodaefolia Ell.) seedlings have been rooted in 4 weeks under mist, after treatment with indolebutyric acid. The technique is suitable for establishing small clones.

Steep cut slope composting : field trials and evaluation.

DOT National Transportation Integrated Search

2011-04-01

Three different depths of compost and five compost retention techniques were tested to determine : their efficacy and cost effectiveness for increasing the establishment of native grass seedings and decreasing : erosion on steep roadside cut slopes i...

Preceding bronchial cutting for exposure of the pulmonary artery buried in scar tissue after chemoradiotherapy.

PubMed

Nomori, Hiroaki; Cong, Yue; Sugimura, Hiroshi

2017-01-01

It is often difficult to expose the pulmonary artery buried in a scar tissue, especially in lung cancer patients that responded well to neoadjuvant chemoradiotherapy. Difficulty to access pulmonary artery branches may lead to potentially unnecessary pneumonectomy. To complete lobectomy in such cases, a technique with preceding bronchial cutting for exposure of the pulmonary artery is presented. After dissecting the pulmonary vein, the lobar bronchus is cut from the opposite side of the pulmonary artery with scissors. The back wall of the lobar bronchus is cut using a surgical knife from the luminal face, which can expose the pulmonary artery behind the bronchial stump and then complete lobectomy. Fourteen patients have been treated using the present technique, enabling complete resection by lobectomy (including sleeve lobectomy in 3 patients) without major bleeding. The present procedure can expose pulmonary artery buried in scar tissue, resulting in making the lobectomy safer.

Numerical approach in defining milling force taking into account curved cutting-edge of applied mills

NASA Astrophysics Data System (ADS)

Bondarenko, I. R.

2018-03-01

The paper tackles the task of applying the numerical approach to determine the cutting forces of carbon steel machining with curved cutting edge mill. To solve the abovementioned task the curved surface of the cutting edge was subject to step approximation, and the chips section was split into discrete elements. As a result, the cutting force was defined as the sum of elementary forces observed during the cut of every element. Comparison and analysis of calculations with regard to the proposed method and the method with Kienzle dependence showed its sufficient accuracy, which makes it possible to apply the method in practice.

Fabrication of Ge-on-insulator wafers by Smart-CutTM with thermal management for undamaged donor Ge wafers

NASA Astrophysics Data System (ADS)

Kim, Munho; Cho, Sang June; Jayeshbhai Dave, Yash; Mi, Hongyi; Mikael, Solomon; Seo, Jung-Hun; Yoon, Jung U.; Ma, Zhenqiang

2018-01-01

Newly engineered substrates consisting of semiconductor-on-insulator are gaining much attention as starting materials for the subsequent transfer of semiconductor nanomembranes via selective etching of the insulating layer. Germanium-on-insulator (GeOI) substrates are critically important because of the versatile applications of Ge nanomembranes (Ge NMs) toward electronic and optoelectronic devices. Among various fabrication techniques, the Smart-CutTM technique is more attractive than other methods because a high temperature annealing process can be avoided. Another advantage of Smart-CutTM is the reusability of the donor Ge wafer. However, it is very difficult to realize an undamaged Ge wafer because there exists a large mismatch in the coefficient of thermal expansion among the layers. Although an undamaged donor Ge wafer is a prerequisite for its reuse, research related to this issue has not yet been reported. Here we report the fabrication of 4-inch GeOI substrates using the direct wafer bonding and Smart-CutTM process with a low thermal budget. In addition, a thermo-mechanical simulation of GeOI was performed by COMSOL to analyze induced thermal stress in each layer of GeOI. Crack-free donor Ge wafers were obtained by annealing at 250 °C for 10 h. Raman spectroscopy and x-ray diffraction (XRD) indicated similarly favorable crystalline quality of the Ge layer in GeOI compared to that of bulk Ge. In addition, Ge p-n diodes using transferred Ge NM indicate a clear rectifying behavior with an on and off current ratio of 500 at ±1 V. This demonstration offers great promise for high performance transferrable Ge NM-based device applications.

Dual Laser-Assisted Lamellar Anterior Keratoplasty with Tophat Graft: A Laboratory Study

PubMed Central

Cleary, Catherine; Song, Jonathan C.; Tang, Maolong; Li, Yan; Liu, Ying; Yiu, Samuel; Huang, David

2011-01-01

Objectives To develop a dual laser-assisted lamellar anterior keratoplasty (LALAK) technique, using excimer and femtosecond lasers to perform surgery on eye-bank eyes. Methods First we compared corneal stromal surfaces produced by (1) deep excimer ablation, (2) femtosecond lamellar cuts, and (3) manual dissection, and evaluated the effect of excimer laser smoothing with fluid masking on each surface. Masked observers graded scanning electron microscopy (SEM) images on a 5-point roughness scale. Then we performed a 6-mm diameter excimer laser phototherapeutic keratectomy (PTK) ablation to a residual bed thickness of 200μm, followed by laser smoothing. We used the femtosecond laser to cut donors in a modified top-hat design with a thin tapered brim, which fitted into a manually dissected circumferential pocket at the base of the recipient bed. Fourier-domain optical coherence tomography (OCT) was used to measure corneal pachymetry and evaluate graft fit. Results Deep excimer ablation with smoothing (n=4) produced a significantly (p<0.05) smoother surface (grade=3.5) than deep excimer alone (n=4, grade=3.8) or manual dissection with (n=1, grade=3.8) and without smoothing (n=1, grade=4.8). Deep femtosecond cuts (n=2) produced macroscopic concentric ridges on the stromal surface. Experimental LALAK was performed on 4 recipients prepared by deep excimer ablation and 4 donors cut with the femtosecond laser. After suturing good peripheral graft-host match was observed on FD-OCT imaging. Conclusion These preliminary studies show that the LALAK technique permits improved interface smoothness and graft edge matching. Clinical trials are needed to determine whether these improvements can translate to better vision. PMID:22378114

Theoretical and experimental aspects of laser cutting with a direct diode laser

NASA Astrophysics Data System (ADS)

Costa Rodrigues, G.; Pencinovsky, J.; Cuypers, M.; Duflou, J. R.

2014-10-01

Recent developments in beam coupling techniques have made it possible to scale up the power of diode lasers with a laser beam quality suitable for laser cutting of metal sheets. In this paper a prototype of a Direct Diode Laser (DDL) source (BPP of 22 mm-mrad) is analyzed in terms of efficiency and cut performance and compared with two established technologies, CO2 and fiber lasers. An analytical model based on absorption calculations is used to predict the performance of the studied laser source with a good agreement with experimental results. Furthermore results of fusion cutting of stainless steel and aluminium alloys as well as oxygen cutting of structural steel are presented, demonstrating that industrial relevant cutting speeds with high cutting quality can now be achieved with DDL.

Rapid fabrication of miniature lens arrays by four-axis single point diamond machining

PubMed Central

McCall, Brian; Tkaczyk, Tomasz S.

2013-01-01

A novel method for fabricating lens arrays and other non-rotationally symmetric free-form optics is presented. This is a diamond machining technique using 4 controlled axes of motion – X, Y, Z, and C. As in 3-axis diamond micro-milling, a diamond ball endmill is mounted to the work spindle of a 4-axis ultra-precision computer numerical control (CNC) machine. Unlike 3-axis micro-milling, the C-axis is used to hold the cutting edge of the tool in contact with the lens surface for the entire cut. This allows the feed rates to be doubled compared to the current state of the art of micro-milling while producing an optically smooth surface with very low surface form error and exceptionally low radius error. PMID:23481813

Numerical Investigation of the Effect of Some Parameters on Temperature Field and Kerf Width in Laser Cutting Process

NASA Astrophysics Data System (ADS)

Kheloufi, Karim; Amara, El Hachemi

A transient numerical model is developed to study the temperature field and the kerf shape during laser cutting process. The Fresnel absorption model is used to handle the absorption of the incident wave by the surface of the liquid metal and the enthalpy-porosity technique is employed to account for the latent heat during melting and solidification of the material. The VOF method is used to track the evolution of the shape of the kerf. Physical phenomena occurring at the liquid/gas interface, including friction force and pressure force exerted by the gas jet and the heat absorbed by the surface, are incorporated into the governing equations as source terms. Temperature and velocity distribution, and kerf shape are investigated.

A Comparison of Cut Scores Using Multiple Standard Setting Methods.

ERIC Educational Resources Information Center

Impara, James C.; Plake, Barbara S.

This paper reports the results of using several alternative methods of setting cut scores. The methods used were: (1) a variation of the Angoff method (1971); (2) a variation of the borderline group method; and (3) an advanced impact method (G. Dillon, 1996). The results discussed are from studies undertaken to set the cut scores for fourth grade…

ANN-PSO Integrated Optimization Methodology for Intelligent Control of MMC Machining

NASA Astrophysics Data System (ADS)

Chandrasekaran, Muthumari; Tamang, Santosh

2017-08-01

Metal Matrix Composites (MMC) show improved properties in comparison with non-reinforced alloys and have found increased application in automotive and aerospace industries. The selection of optimum machining parameters to produce components of desired surface roughness is of great concern considering the quality and economy of manufacturing process. In this study, a surface roughness prediction model for turning Al-SiCp MMC is developed using Artificial Neural Network (ANN). Three turning parameters viz., spindle speed ( N), feed rate ( f) and depth of cut ( d) were considered as input neurons and surface roughness was an output neuron. ANN architecture having 3 -5 -1 is found to be optimum and the model predicts with an average percentage error of 7.72 %. Particle Swarm Optimization (PSO) technique is used for optimizing parameters to minimize machining time. The innovative aspect of this work is the development of an integrated ANN-PSO optimization method for intelligent control of MMC machining process applicable to manufacturing industries. The robustness of the method shows its superiority for obtaining optimum cutting parameters satisfying desired surface roughness. The method has better convergent capability with minimum number of iterations.

Combined measurement system for double shield tunnel boring machine guidance based on optical and visual methods.

PubMed

Lin, Jiarui; Gao, Kai; Gao, Yang; Wang, Zheng

2017-10-01

In order to detect the position of the cutting shield at the head of a double shield tunnel boring machine (TBM) during the excavation, this paper develops a combined measurement system which is mainly composed of several optical feature points, a monocular vision sensor, a laser target sensor, and a total station. The different elements of the combined system are mounted on the TBM in suitable sequence, and the position of the cutting shield in the reference total station frame is determined by coordinate transformations. Subsequently, the structure of the feature points and matching technique for them are expounded, the position measurement method based on monocular vision is presented, and the calibration methods for the unknown relationships among different parts of the system are proposed. Finally, a set of experimental platforms to simulate the double shield TBM is established, and accuracy verification experiments are conducted. Experimental results show that the mean deviation of the system is 6.8 mm, which satisfies the requirements of double shield TBM guidance.

To cut or not to cut? Assessing the modular structure of brain networks.

PubMed

Chang, Yu-Teng; Pantazis, Dimitrios; Leahy, Richard M

2014-05-01

A wealth of methods has been developed to identify natural divisions of brain networks into groups or modules, with one of the most prominent being modularity. Compared with the popularity of methods to detect community structure, only a few methods exist to statistically control for spurious modules, relying almost exclusively on resampling techniques. It is well known that even random networks can exhibit high modularity because of incidental concentration of edges, even though they have no underlying organizational structure. Consequently, interpretation of community structure is confounded by the lack of principled and computationally tractable approaches to statistically control for spurious modules. In this paper we show that the modularity of random networks follows a transformed version of the Tracy-Widom distribution, providing for the first time a link between module detection and random matrix theory. We compute parametric formulas for the distribution of modularity for random networks as a function of network size and edge variance, and show that we can efficiently control for false positives in brain and other real-world networks. Copyright © 2014 Elsevier Inc. All rights reserved.

Applying a crop-tree release in small-sawtimber white oak stands

Treesearch

Jeffrey W Stringer; Gary W. Miller; Robert F. Wittwer; Robert F. Wittwer

1988-01-01

Small-sawtimber white oak crop trees in Kentucky were released by a crown-touching technique. In two cutting treatments, 20 and 34 crop trees were released per acre at a total cost of $35 and $42, respectively. Both treatments yielded commercial volumes of cut material. Total mean merchantable volume (> 5.0 inches d.b.h.) in cut trees was 693 cubic feet/acre, with...

3D interferometric shape measurement technique using coherent fiber bundles

NASA Astrophysics Data System (ADS)

Zhang, Hao; Kuschmierz, Robert; Czarske, Jürgen

2017-06-01

In-situ 3-D shape measurements with submicron shape uncertainty of fast rotating objects in a cutting lathe are expected, which can be achieved by simultaneous distance and velocity measurements. Conventional tactile methods, coordinate measurement machines, only support ex-situ measurements. Optical measurement techniques such as triangulation and conoscopic holography offer only the distance, so that the absolute diameter cannot be retrieved directly. In comparison, laser Doppler distance sensors (P-LDD sensor) enable simultaneous and in-situ distance and velocity measurements for monitoring the cutting process in a lathe. In order to achieve shape measurement uncertainties below 1 μm, a P-LDD sensor with a dual camera based scattered light detection has been investigated. Coherent fiber bundles (CFB) are employed to forward the scattered light towards cameras. This enables a compact and passive sensor head in the future. Compared with a photo detector based sensor, the dual camera based sensor allows to decrease the measurement uncertainty by the order of one magnitude. As a result, the total shape uncertainty of absolute 3-D shape measurements can be reduced to about 100 nm.

High pressure water jet cutting and stripping

NASA Technical Reports Server (NTRS)

Hoppe, David T.; Babai, Majid K.

1991-01-01

High pressure water cutting techniques have a wide range of applications to the American space effort. Hydroblasting techniques are commonly used during the refurbishment of the reusable solid rocket motors. The process can be controlled to strip a thermal protective ablator without incurring any damage to the painted surface underneath by using a variation of possible parameters. Hydroblasting is a technique which is easily automated. Automation removes personnel from the hostile environment of the high pressure water. Computer controlled robots can perform the same task in a fraction of the time that would be required by manual operation.

Real-time surgical simulation for deformable soft-tissue objects with a tumour using Boundary Element techniques

NASA Astrophysics Data System (ADS)

Wang, P.; Becker, A. A.; Jones, I. A.; Glover, A. T.; Benford, S. D.; Vloeberghs, M.

2009-08-01

A virtual-reality real-time simulation of surgical operations that incorporates the inclusion of a hard tumour is presented. The software is based on Boundary Element (BE) technique. A review of the BE formulation for real-time analysis of two-domain deformable objects, using the pre-solution technique, is presented. The two-domain BE software is incorporated into a surgical simulation system called VIRS to simulate the initiation of a cut on the surface of the soft tissue and extending the cut deeper until the tumour is reached.

Image fidelity improvement in digital holographic microscopy using optical phase conjugation

NASA Astrophysics Data System (ADS)

Chan, Huang-Tian; Chew, Yang-Kun; Shiu, Min-Tzung; Chang, Chi-Ching

2018-01-01

With respect to digital holography, techniques in suppressing noises derived from reference arm are maturely developed. However, techniques for the object counterpart are not being well developed. Optical phase conjugation technique was believed to be a promising method for this interest. A 0°-cut BaTiO3 photorefractive crystal was involved in self-pumped phase conjugation scheme, and was employed to in-line digital holographic microscopy, in both transmission-type and reflection-type configuration. On pure physical compensation basis, results revealed that the image fidelity was improved substantially with 2.9096 times decrease in noise level and 3.5486 times increase in the ability to discriminate noise on average, by suppressing the scattering noise prior to recording stage.

Study on Roadheader Cutting Load at Different Properties of Coal and Rock

PubMed Central

2013-01-01

The mechanism of cutting process of roadheader with cutting head was researched, and the influences of properties of coal and rock on cutting load were deeply analyzed. Aimed at the defects of traditional calculation method of cutting load on fully expressing the complex cutting process of cutting head, the method of finite element simulation was proposed to simulate the dynamic cutting process. Aimed at the characteristics of coal and rock which affect the cutting load, several simulations with different firmness coefficient were taken repeatedly, and the relationship between three-axis force and firmness coefficient was derived. A comparative analysis of cutting pick load between simulation results and theoretical formula was carried out, and a consistency was achieved. Then cutting process with a total cutting head was carried out on this basis. The results show that the simulation analysis not only provides a reliable guarantee for the accurate calculation of the cutting head load and improves the efficiency of the cutting head cutting test but also offers a basis for selection of cutting head with different geological conditions of coal or rock. PMID:24302866

Overview of nanofluid application through minimum quantity lubrication (MQL) in metal cutting process

NASA Astrophysics Data System (ADS)

Sharif, Safian; Sadiq, Ibrahim Ogu; Suhaimi, Mohd Azlan; Rahim, Shayfull Zamree Abd

2017-09-01

Pollution related activities in addition to handling cost of conventional cutting fluid application in metal cutting industry has generated a lot of concern over time. The desire for a green machining environment which will preserve the environment through reduction or elimination of machining related pollution, reduction in oil consumption and safety of the machine operators without compromising an efficient machining process led to search for alternatives to conventional cutting fluid. Amongst the alternatives of dry machining, cryogenic cooling, high pressure cooling, near dry or minimum quantity lubrication (MQL), MQL have shown remarkable performance in terms of cost, machining output, safety of environment and machine operators. However, the MQL under aggressive machining or very high speed machining pose certain restriction as the lubrication media cannot perform efficiently at elevated temperature. In compensating for the shortcomings of MQL technique, high thermal conductivity nanoparticles are introduced in cutting fluids for use in the MQL lubrication process. They have indicated enhanced performance of machining process and significant reduction of loads on the environment. The present work is aimed at evaluating the application and performance of nanofluid in metal cutting process through MQL lubrication technique highlighting their impacts and prospects as lubrication strategy in metal cutting process for sustainable green manufacturing. Enhanced performance of vegetable oil based nanofluids over mineral oil-based nanofluids have been reported and thus highlighted.

Density-based empirical likelihood procedures for testing symmetry of data distributions and K-sample comparisons.

PubMed

Vexler, Albert; Tanajian, Hovig; Hutson, Alan D

In practice, parametric likelihood-ratio techniques are powerful statistical tools. In this article, we propose and examine novel and simple distribution-free test statistics that efficiently approximate parametric likelihood ratios to analyze and compare distributions of K groups of observations. Using the density-based empirical likelihood methodology, we develop a Stata package that applies to a test for symmetry of data distributions and compares K -sample distributions. Recognizing that recent statistical software packages do not sufficiently address K -sample nonparametric comparisons of data distributions, we propose a new Stata command, vxdbel, to execute exact density-based empirical likelihood-ratio tests using K samples. To calculate p -values of the proposed tests, we use the following methods: 1) a classical technique based on Monte Carlo p -value evaluations; 2) an interpolation technique based on tabulated critical values; and 3) a new hybrid technique that combines methods 1 and 2. The third, cutting-edge method is shown to be very efficient in the context of exact-test p -value computations. This Bayesian-type method considers tabulated critical values as prior information and Monte Carlo generations of test statistic values as data used to depict the likelihood function. In this case, a nonparametric Bayesian method is proposed to compute critical values of exact tests.

Sound propagation in and radiation from acoustically lined flow ducts: A comparison of experiment and theory

NASA Technical Reports Server (NTRS)

Plumblee, H. E., Jr.; Dean, P. D.; Wynne, G. A.; Burrin, R. H.

1973-01-01

The results of an experimental and theoretical study of many of the fundamental details of sound propagation in hard wall and soft wall annular flow ducts are reported. The theory of sound propagation along such ducts and the theory for determining the complex radiation impedance of higher order modes of an annulus are outlined, and methods for generating acoustic duct modes are developed. The results of a detailed measurement program on propagation in rigid wall annular ducts with and without airflow through the duct are presented. Techniques are described for measuring cut-on frequencies, modal phase speed, and radial and annular mode shapes. The effects of flow velocity on cut-on frequencies and phase speed are measured. Comparisons are made with theoretical predictions for all of the effects studies. The two microphone method of impedance is used to measure the effects of flow on acoustic liners. A numerical study of sound propagation in annular ducts with one or both walls acoustically lined is presented.

A cut-cell immersed boundary technique for fire dynamics simulation

NASA Astrophysics Data System (ADS)

Vanella, Marcos; McDermott, Randall; Forney, Glenn

2015-11-01

Fire simulation around complex geometry is gaining increasing attention in performance based design of fire protection systems, fire-structure interaction and pollutant transport in complex terrains, among others. This presentation will focus on our present effort in improving the capability of FDS (Fire Dynamics Simulator, developed at the Fire Research Division, NIST. https://github.com/firemodels/fds-smv) to represent fire scenarios around complex bodies. Velocities in the vicinity of the bodies are reconstructed using a classical immersed boundary scheme (Fadlun and co-workers, J. Comput. Phys., 161:35-60, 2000). Also, a conservative treatment of scalar transport equations (i.e. for chemical species) will be presented. In our method, discrete conservation and no penetration of species across solid boundaries are enforced using a cut-cell finite volume scheme. The small cell problem inherent to the method is tackled using explicit-implicit domain decomposition for scalar, within the FDS time integration scheme. Some details on the derivation, implementation and numerical tests of this numerical scheme will be discussed.

Southern Pine Beetle Survival In Trees Felled By the Cut and Top-Cut and Leave Method

Treesearch

J.D. Hodges; R.C. Thatcher

1976-01-01

When the cut & top-cut & leave method was used for control of the southern pine beetle in Central Louisiana, trees were felled into the open or into shade in September, June, July, December, and January. Survival was greatest in September, moderate in July, and relatively low in June, December, and January. The cut and top treatment resulted in lower beetle...

Comparative study of pulsed laser cleaning applied to weathered marble surfaces

NASA Astrophysics Data System (ADS)

Ortiz, P.; Antúnez, V.; Ortiz, R.; Martín, J. M.; Gómez, M. A.; Hortal, A. R.; Martínez-Haya, B.

2013-10-01

The removal of unwanted matter from surface stones is a demanding task in the conservation of cultural heritage. This paper investigates the effectiveness of near-infrared (IR) and ultraviolet (UV) laser pulses for the cleaning of surface deposits, iron oxide stains and different types of graffiti (black, red and green sprays and markers, and black cutting-edge ink) on dolomitic white marble. The performance of the laser techniques is compared to common cleaning methods on the same samples, namely pressurized water and chemical treatments. The degree of cleaning achieved with each technique is assessed by means of colorimetric measurements and X-ray microfluorescence. Eventual morphological changes induced on the marble substrate are monitored with optical and electronic microscopy. It is found that UV pulsed laser ablation at 266 nm manages to clean all the stains except the cutting-edge ink, although some degree of surface erosion is produced. The IR laser pulses at 1064 nm can remove surface deposits and black spray acceptably, but a yellowing is observed on the stone surface after treatment. An economic evaluation shows that pulsed laser cleaning techniques are advantageous for the rapid cleaning of small or inaccessible surface areas, although their extensive application becomes expensive due to the long operating times required.

Optimum design of space storable gas/liquid coaxial injectors.

NASA Technical Reports Server (NTRS)

Burick, R. J.

1972-01-01

Review of the results of a program of single-element, cold-flow/hot-fire experiments performed for the purpose of establishing design criteria for a high-performance gas/liquid (FLOX/CH4) coaxial injector. The approach and the techniques employed resulted in the direct design of an injector that met or exceeded the performance and chamber compatibility goals of the program without any need for the traditional 'cut-and-try' development methods.

Spatial Statistics of Large Astronomical Databases: An Algorithmic Approach

NASA Technical Reports Server (NTRS)

Szapudi, Istvan

2004-01-01

In this AISRP, the we have demonstrated that the correlation function i) can be calculated for MAP in minutes (about 45 minutes for Planck) on a modest 500Mhz workstation ii) the corresponding method, although theoretically suboptimal, produces nearly optimal results for realistic noise and cut sky. This trillion fold improvement in speed over the standard maximum likelihood technique opens up tremendous new possibilities, which will be persued in the follow up.

Characteristics and Machining Performance of TiN and TiAlN Coatings on a Milling Cutter

NASA Astrophysics Data System (ADS)

Sarwar, Mohammed; Haider, Julfikar

2011-01-01

Titanium Nitride (TiN) coating deposited by Physical Vapour Deposition (PVD) or Chemical Vapour Deposition (CVD) techniques on cutting tools (single point or multipoint) has contributed towards the improvement of tool life, productivity and product quality [1]. Addition of Al in TiN coating (e.g., TiAlN or AlTiN) has further improved the coating properties required for machining applications [2, 3]. This work presents a comparative investigation on TiN and TiAlN coatings deposited on to a Powder Metallurgy High Speed Steel (PM HSS) milling cutter used for machining bimetal (M42+D6A) steel strips. PVD (Arc evaporation) technique was used to deposit the coatings after carefully preparing the cutting edges of the milling cutter. Microstructure, chemical composition, hardness and adhesion of the coatings have been characterised using different techniques. The incorporation of Al into TiN coating results in an improvement in hardness, wear resistance and cutting performance. Examination of the worn flank in the coated cutting edges revealed that abrasive and adhesive wear are the predominant failure mechanisms. Tool designers, coating suppliers and manufacturing engineers could benefit from the information provided.

A New Approach for the Correction of Prominent Ear Deformity: The Distally Based Perichondrio-Adipo-Dermal Flap Technique.

PubMed

Cihandide, Ercan; Kayiran, Oguz; Aydin, Elif Eren; Uzunismail, Adnan

2016-06-01

Otoplasty techniques are generally divided into 2 categories as cartilage-cutting and cartilage-sparing. The cartilage-cutting techniques have been criticized because of their high risk of hematoma, skin necrosis, and ear deformity. As a result, suture-based cartilage-sparing methods like Mustardé and Furnas-type suture techniques have become increasingly popular. However, with these techniques postauricular suture extrusion may be seen and recurrence rates of up to 25% have been reported. In this study, cartilage-sparing otoplasty is redefined by introduction of the distally based perichondrio-adipo-dermal flap which is elevated from the postauricular region. Thirty-seven ears (17 bilateral and 3 unilateral) in 20 patients (14 females and 6 males) have been operated with the defined technique by the same surgeon. The distally based perichondrio-adipo-dermal flap is advanced posteriorly to correct the deformity, also acting as a strong postauricular support to prevent recurrence. In addition to the resultant natural-looking antihelical fold, the posterior advancement of the flap corrects both the otherwise wide conchoscaphal and conchomastoid angles. The operative technique is explained in detail with results and the literature is reviewed. There were no hematomas. After an average follow-up of 8.3 months (2-16 months), recurrence was seen in only 1 patient who requested no further surgery. No patients developed suture extrusion or granuloma. The authors introduce a simple and safe procedure to correct prominent ears with benefits including a resultant natural-looking antihelical fold and less tissue trauma. The distally based perichondrio-adipo-dermal flap seems to prevent suture extrusion and may also help to reduce recurrence rates. By forming neochondrogenesis which is stimulated by elevation of the perichondrium, this flap gives the promise of longer durability of the newly formed antihelical fold.

Tool path strategy and cutting process monitoring in intelligent machining

NASA Astrophysics Data System (ADS)

Chen, Ming; Wang, Chengdong; An, Qinglong; Ming, Weiwei

2018-06-01

Intelligent machining is a current focus in advanced manufacturing technology, and is characterized by high accuracy and efficiency. A central technology of intelligent machining—the cutting process online monitoring and optimization—is urgently needed for mass production. In this research, the cutting process online monitoring and optimization in jet engine impeller machining, cranio-maxillofacial surgery, and hydraulic servo valve deburring are introduced as examples of intelligent machining. Results show that intelligent tool path optimization and cutting process online monitoring are efficient techniques for improving the efficiency, quality, and reliability of machining.

CAD/CAM machining Vs pre-sintering in-lab fabrication techniques of Y-TZP ceramic specimens: Effects on their mechanical fatigue behavior.

PubMed

Zucuni, C P; Guilardi, L F; Fraga, S; May, L G; Pereira, G K R; Valandro, L F

2017-07-01

This study evaluated the effects of different pre-sintering fabrication processing techniques of Y-TZP ceramic (CAD/CAM Vs. in-lab), considering surface characteristics and mechanical performance outcomes. Pre-sintered discs of Y-TZP ceramic (IPS e.max ZirCAD, Ivoclar Vivadent) were produced using different pre-sintering fabrication processing techniques: Machined- milling with a CAD/CAM system; Polished- fabrication using a cutting device followed by polishing (600 and 1200 SiC papers); Xfine- fabrication using a cutting machine followed by grinding with extra-fine diamond bur (grit size 30 μm); Fine- fabrication using a cutting machine followed by grinding with fine diamond bur (grit size 46 μm); SiC- fabrication using a cutting machine followed by grinding with 220 SiC paper. Afterwards, the discs were sintered and submitted to roughness (n=35), surface topography (n=2), phase transformation (n=2), biaxial flexural strength (n=20), and biaxial flexural fatigue strength (fatigue limit) (n=15) analyses. No monoclinic-phase content was observed in all processing techniques. It can be observed that obtaining a surface with similar characteristics to CAD/CAM milling is essential for the observation of similar mechanical performance. On this sense, grinding with fine diamond bur before sintering (Fine group) was the best mimic protocol in comparison to the CAD/CAM milling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exploiting jet binning to identify the initial state of high-mass resonances

NASA Astrophysics Data System (ADS)

Ebert, Markus A.; Liebler, Stefan; Moult, Ian; Stewart, Iain W.; Tackmann, Frank J.; Tackmann, Kerstin; Zeune, Lisa

2016-09-01

If a new high-mass resonance is discovered at the Large Hadron Collider, model-independent techniques to identify the production mechanism will be crucial to understand its nature and effective couplings to Standard Model particles. We present a powerful and model-independent method to infer the initial state in the production of any high-mass color-singlet system by using a tight veto on accompanying hadronic jets to divide the data into two mutually exclusive event samples (jet bins). For a resonance of several hundred GeV, the jet binning cut needed to discriminate quark and gluon initial states is in the experimentally accessible range of several tens of GeV. It also yields comparable cross sections for both bins, making this method viable already with the small event samples available shortly after a discovery. Theoretically, the method is made feasible by utilizing an effective field theory setup to compute the jet cut dependence precisely and model independently and to systematically control all sources of theoretical uncertainties in the jet binning, as well as their correlations. We use a 750 GeV scalar resonance as an example to demonstrate the viability of our method.

Micropropagation systems of Feijoa (Acca sellowiana (O. Berg) Burret).

PubMed

Guerra, Miguel Pedro; Cangahuala-Inocente, Gabriela Claudia; Vesco, Lirio Luiz Dal; Pescador, Rosete; Caprestano, Clarissa Alves

2013-01-01

Acca sellowiana (O. Berg) Burret sin. Feijoa sellowiana (Myrtaceae) is a semiwoody fruit species native to South Brazil, Uruguay, and Argentina; edible fruits are tasty. The naturally occurring populations in Santa Catarina State show high variability in fruit size, color, and other features. A breeding program launched in 1990 resulted in the release of four Brazilian commercial varieties. The conventional clonal propagation methods of this species, such as cutting and grafting, have shown low efficiency. Therefore, tissue culture techniques were developed for mass propagation. This chapter describes several protocols based on organogenesis and somatic embryogenesis. Additional techniques including synthetic seed technology and temporary immersion system are also described.

Extended asymmetric-cut multilayer X-ray gratings.

PubMed

Prasciolu, Mauro; Haase, Anton; Scholze, Frank; Chapman, Henry N; Bajt, Saša

2015-06-15

The fabrication and characterization of a large-area high-dispersion blazed grating for soft X-rays based on an asymmetric-cut multilayer structure is reported. An asymmetric-cut multilayer structure acts as a perfect blazed grating of high efficiency that exhibits a single diffracted order, as described by dynamical diffraction throughout the depth of the layered structure. The maximum number of grating periods created by cutting a multilayer deposited on a flat substrate is equal to the number of layers deposited, which limits the size of the grating. The size limitation was overcome by depositing the multilayer onto a substrate which itself is a coarse blazed grating and then polish it flat to reveal the uniformly spaced layers of the multilayer. The number of deposited layers required is such that the multilayer thickness exceeds the step height of the substrate structure. The method is demonstrated by fabricating a 27,060 line pairs per mm blazed grating (36.95 nm period) that is repeated every 3,200 periods by the 120-μm period substrate structure. This preparation technique also relaxes the requirements on stress control and interface roughness of the multilayer film. The dispersion and efficiency of the grating is demonstrated for soft X-rays of 13.2 nm wavelength.

Two multidimensional chromatographic methods for enantiomeric analysis of o,p'-DDT and o,p'-DDD in contaminated soil and air in a malaria area of South Africa.

PubMed

Naudé, Yvette; Rohwer, Egmont R

2012-06-12

In rural parts of South Africa the organochlorine insecticide DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is still used for malaria vector control where traditional dwellings are sprayed on the inside with small quantities of technical DDT. Since o,p'-DDT may show enantioselective oestrogenicity and biodegradability, it is important to analyse enantiomers of o,p'-DDT and its chiral degradation product, o,p'-DDD, for both health and environmental-forensic considerations. Generally, chiral analysis is performed using heart-cut multidimensional gas chromatography (MDGC) and, more recently, comprehensive two-dimensional gas chromatography (GC×GC). We developed an off-line gas chromatographic fraction collection (heart-cut) procedure for the selective capturing of the appropriate isomers from a first apolar column, followed by reinjection and separation on a second chiral column. Only the o,p'-isomers of DDT and DDD fractions from the first dimension complex chromatogram (achiral apolar GC column separation) were selectively collected onto a polydimethylsiloxane (PDMS) multichannel open tubular silicone rubber trap by simply placing the latter device on the flame tip of an inactivated flame ionisation detector (FID). The multichannel trap containing the o,p'-heart-cuts was then thermally desorbed into a GC with time-of-flight mass spectrometry detection (GC-TOFMS) for second dimension enantioselective separation on a chiral column (β-cyclodextrin-based). By selectively capturing only the o,p'-isomers from the complex sample chromatogram, (1)D separation of ultra-trace level enantiomers could be achieved on the second chiral column without matrix interference. Here, we present solventless concentration techniques for extraction of DDT from contaminated soil and air, and report enantiomeric fraction (EF) values of o,p'-DDT and o,p'-DDD obtained by a new multidimensional approach for heart-cut gas chromatographic fraction collection for off-line second dimension enantiomeric separation by (1)D GC-TOFMS of selected isomers. This multidimensional method is compared to the complementary technique of comprehensive GC×GC-TOFMS using the same enantioselective column, this time as the first dimension of separation. Copyright © 2012 Elsevier B.V. All rights reserved.

Modified Cheeger and Ratio Cut Methods Using the Ginzburg-Landau Functional for Classification of High-Dimensional Data

DTIC Science & Technology

2016-02-01

Modified Cheeger and Ratio Cut Methods Using the Ginzburg-Landau Functional for Classification of High-Dimensional Data Ekaterina Merkurjev*, Andrea...bertozzi@math.ucla.edu, xiaoran@isi.edu, lerman@isi.edu. Abstract Recent advances in clustering have included continuous relaxations of the Cheeger cut ...fully nonlinear Cheeger cut problem, as well as the ratio cut optimization task. Both problems are connected to total variation minimization, and the

Silver ion chromatography for peak resolution enhancement: Application to the preparative separation of two sesquiterpenes using online heart-cutting LC-LC technique.

PubMed

Yang, Yang; Zhang, Yongmin; Wei, Chong; Li, Jing; Sun, Wenji

2018-09-01

Silver ion chromatography, utilizing columns packed with silver ions bonded to silica gel, has proved to be an invaluable technique for the analysis of some positional isomers. In this work, silver ion chromatography by combination with online heart-cutting LC-LC technique for the preparative separation of two sesquiterpenes positional isomers from a natural product was investigated. On the basis of the evaluation that silver ion content impacts on the separation, the laboratory-made silver ion columns, utilizing silica gel impregnated with 15% silver nitrate as column packing materials, were used for peak resolution improvement of these two isomers and the preparative separation of them in heart-cutting LC-LC. The relationship among the maximal sample load, flow rate and peak resolution in the silver ion column were optimized, and the performance of the silver ion column was compared with conventional C 18 column and silica gel column. Based on the developed chromatographic conditions, online heart-cutting LC-LC chromatographic separation system in combination with a silica gel column and a silver ion column that was applied to preparative separation of these two isomers from a traditional Chinese medicine, Inula racemosa Hook.f., was established. The results showed that the online heart-cutting LC-LC technique by combination of a silica gel column and a silver ion column for the preparative separation of these two positional isomers from this natural plant was superior to the preparative separation performed on a single-column system with C 18 column or silica gel column. Copyright © 2018 Elsevier B.V. All rights reserved.

On-line two-dimensional capillary electrophoresis with mass spectrometric detection using a fully electric isolated mechanical valve.

PubMed

Kohl, Felix J; Montealegre, Cristina; Neusüß, Christian

2016-04-01

CE is becoming more and more important in many fields of bioanalytical chemistry. Besides optical detection, hyphenation to ESI-MS detection is increasingly applied for sensitive identification purposes. Unfortunately, many CE techniques and methods established in research and industry are not compatible to ESI-MS since essential components of the background electrolyte interfere in ES ionization. In order to identify unknown peaks in established CE methods, here, a heart-cut 2D-CE separation system is introduced using a fully isolated mechanical valve with an internal loop of only 20 nL. In this system, the sample is separated using potentially any non-ESI compatible method in the first separation dimension. Subsequently, the portion of interest is cut by the internal sample loop of the valve and reintroduced to the second dimension where the interfering compounds are removed, followed by ESI-MS detection. When comparing the separation efficiency of the system with the valve to a system using a continuous capillary only a slight increase in peak width is observed. Ultraviolet/visible detection is integrated in the first dimension for switching time determination, enabling reproducible cutting of peaks of interest. The feasibility of the system is successfully demonstrated by a 2D analysis of a BSA tryptic digest sample using a nonvolatile (phosphate based) background electrolyte in the first dimension. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Laser vs bur for bone cutting in impacted mandibular third molar surgery: A randomized controlled trial

PubMed Central

Passi, Deepak; Pal, Uma Shankar; Mohammad, Shadab; Singh, Rakesh Kumar; Mehrotra, Divya; Singh, Geeta; Kumar, Manoj; Chellappa, Arul A.L.; Gupta, Chandan

2013-01-01

Background The aim of this study was to assess the feasibility of Er: YAG laser in bone cutting for removal of impacted lower third molar teeth and compare its outcomes with that of surgical bur. Materials & methods The study comprised 40 subjects requiring removal of impacted mandibular third molar, randomly categorized into two equal groups of 20 each, who had their impacted third molar removed either using Er: YAG laser or surgical bur as per their group, using standard methodology of extraction of impacted teeth. Clinical parameters like pain, bleeding, time taken for bone cutting, postoperative swelling, trismus, wound healing and complications were compared for both groups. Observation & result Clinical parameters like pain, bleeding and swelling were lower in laser group than bur group, although the difference was statistically not significant. However, postoperative swelling showed significant difference in the two groups. Laser group required almost double the time taken for bone cutting with bur. Trismus persisted for a longer period in laser group. Wound healing and complications were assessed clinically and there was no significant difference in both the groups. Conclusion Based on the results of our study, the possibility of bone cutting using lasers is pursued, the osteotomy is easily performed and the technique is better suited to minimally invasive surgical procedures. The use of Er: YAG laser may be considered as an alternative tool to surgical bur, specially in anxious patients. PMID:25737885

A comparison of mesial molar root canal preparations using two engine-driven instruments and the balanced-force technique.

PubMed

Imura, N; Kato, A S; Novo, N F; Hata, G; Uemura, M; Toda, T

2001-10-01

The purpose of this study was to compare the effects of two engine-driven, nickel-titanium instrument systems with hand files in the final shape of slight and moderately curved canals. A total of 72 mesial roots of extracted human mandibular molars were divided into three groups: ProFile .04 taper, Pow-R rotary systems, and Flex-R hand-filing technique. The roots were mounted and cross-sectioned at two different horizontal levels using a modified Bramante technique. Pre- and postinstrumented cross-sectional roots were imaged, recorded, and computer analyzed. Results showed that, at the middle third, in almost all groups, there was a tendency of cutting more toward the mesial side with only one exception: Pow-R cut more to the distal side (danger zone) (p < 0.02). At the apical third, Flex-R (p < 0.03) and ProFile (0.001) transported to the mesial side (danger zone) when the curvature increased. When the three techniques were compared analyzing each side and considering the two groups of curvature, at the middle third in the moderately curved-canal group, Flex-R cut statistically more than Pow-R toward the lingual side. The other comparisons showed no statistically significant difference. When the techniques were compared in relation with the degree of curvature, in the apical third, ProFile .04 cut statistically more toward the mesial side in the moderately curved canal group than in the slightly curved canal group. The other comparisons showed no statistically significant difference. Canal preparation time was shorter with hand instrumentation (p < .05) in a few instances.

Debris-free rear-side picosecond laser ablation of thin germanium wafers in water with ethanol

NASA Astrophysics Data System (ADS)

Zhang, Dongshi; Gökce, Bilal; Sommer, Steffen; Streubel, René; Barcikowski, Stephan

2016-03-01

In this paper, we perform liquid-assisted picosecond laser cutting of 150 μm thin germanium wafers from the rear side. By investigating the cutting efficiency (the ability to allow an one-line cut-through) and quality (characterized by groove morphologies on both sides), the pros and cons of this technique under different conditions are clarified. Specifically, with laser fluence fixed, repetition rate and scanning speed are varied to show quality and efficiency control by means of laser parameter modulation. It is found that low repetition rate ablation in liquid gives rise to a better cut quality on the front side than high repetition rate ablation since it avoids dispersed nanoparticles redeposition resulting from a bubble collapse, unlike the case of 100 kHz which leads to large nanorings near the grooves resulting from a strong interaction of bubbles and the case of 50 kHz which leads to random cutting due to the interaction of the former pulse induced cavitation bubble and the subsequent laser pulse. Furthermore, ethanol is mixed with pure distilled water to assess the liquid's impact on the cutting efficiency and cutting quality. The results show that increasing the ethanol fraction decreases the ablation efficiency but simultaneously, greatly improves the cutting quality. The improvement of cut quality as ethanol ratio increases may be attributed to less laser beam interference by a lower density of bubbles which adhere near the cut kerf during ablation. A higher density of bubbles generated from ethanol vaporization during laser ablation in liquid will cause stronger bubble shielding effect toward the laser beam propagation and therefore result in less laser energy available for the cut, which is the main reason for the decrease of cut efficiency in water-ethanol mixtures. Our findings give an insight into under which condition the rear-side laser cutting of thin solar cells should be performed: high repetition, pure distilled water and high laser power are favorable for high-speed rough cutting but the cut kerf suffers from strong side effects of ripples, nanoredeposition occurrence, while low laser power at low repetition rate (10 kHz), mixed solution (1 wt% ethanol in water) and moderate scanning speed (100 μm/s) are preferable for ultrafine high-quality debris-free cutting. The feasibility of high-quality cut is a good indication of using rear laser ablation in liquid to cut thinner wafers. More importantly, this technique spares any post cleaning steps to reduce the risk to the contamination or crack of the thin wafers.

Novel use of cutting balloon to treat subintimal hematomas during chronic total occlusion interventions.

PubMed

Vo, Minh N; Brilakis, Emmanouil S; Grantham, J Aaron

2018-01-01

Contemporary chronic total occlusion (CTO) percutaneous coronary interventional (PCI) techniques are increasingly dependent upon dissection and reentry techniques (DARTs) especially for long occluded lesions. DARTs can result in compressive hematomas during CTO interventions and traditional treatment with balloon angioplasty and/or coronary stenting are often suboptimal and may extend the hematoma distally. We describe the novel use of a cutting balloon to "express" these compressive hematomas and restore antegrade coronary blood flow. © 2017 Wiley Periodicals, Inc.

Diamond tool wear detection method using cutting force and its power spectrum analysis in ultra-precision fly cutting

NASA Astrophysics Data System (ADS)

Zhang, G. Q.; To, S.

2014-08-01

Cutting force and its power spectrum analysis was thought to be an effective method monitoring tool wear in many cutting processes and a significant body of research has been conducted on this research area. However, relative little similar research was found in ultra-precision fly cutting. In this paper, a group of experiments were carried out to investigate the cutting forces and its power spectrum characteristics under different tool wear stages. Result reveals that the cutting force increases with the progress of tool wear. The cutting force signals under different tool wear stages were analyzed using power spectrum analysis. The analysis indicates that a characteristic frequency does exist in the power spectrum of the cutting force, whose power spectral density increases with the increasing of tool wear level, this characteristic frequency could be adopted to monitor diamond tool wear in ultra-precision fly cutting.

26 CFR 1.669(c)-3A - Information requirements with respect to beneficiary.

Code of Federal Regulations, 2010 CFR

2010-04-01

... year for which a recomputation is required under either the exact method or the short-cut method. Such... computed under paragraph (c) of § 1.669(b)-1A (the short-cut method) shall be deemed to be the amount of... this rule where the short-cut method is not permitted. If he cannot furnish the information required...

26 CFR 1.668(b)-4A - Information requirements with respect to beneficiary.

Code of Federal Regulations, 2010 CFR

2010-04-01

... which a recomputation is required under either the exact method or the short-cut method. Such... computed under paragraph (c) of § 1.668(b)-1A (the short-cut method) shall be deemed to be the amount of... this rule where the short-cut method is not permitted. If he cannot furnish the information required...

Optimization of Machining Parameters of Milling Operation by Application of Semi-synthetic oil based Nano cutting Fluids

NASA Astrophysics Data System (ADS)

Giri Prasad, M. J.; Abhishek Raaj, A. S.; Rishi Kumar, R.; Gladson, Frank; M, Gautham

2016-09-01

The present study is concerned with resolving the problems pertaining to the conventional cutting fluids. Two samples of nano cutting fluids were prepared by dispersing 0.01 vol% of MWCNTs and a mixture of 0.01 vol% of MWCNTs and 0.01 vol% of nano ZnO in the soluble oil. The thermophysical properties such as the kinematic viscosity, density, flash point and the tribological properties of the prepared nano cutting fluid samples were experimentally investigated and were compared with those of plain soluble oil. In addition to this, a milling process was carried by varying the process parameters and by application of different samples of cutting fluids and an attempt was made to determine optimal cutting condition using the Taguchi optimization technique.

[Cesarean section by the Misgav Ladach+ with the abdominal opening surgery by the Joel Cohen method].

PubMed

Zienkowicz, Z; Suchocki, S; Sleboda, H; Bojarski, M

2000-04-01

The purpose of this study was to compare 90 Misgav-Ladach cesarean section by the Joel-Cohen method with 45 others with Pfannenstiel incision. The Misgav-Ladach technique involves the Joel-Cohen method, that is a superficial transverse cut in the cutis, a small midline incision in the fascia, then blunt preparation of deeper layers, including the peritoneum, followed by manual transverse traction applied to tear the recti muscles and subcutis. The uterus is also opened using the blunt preparation after a small cut in the midline. After the delivery of the fetus and placenta the uterus is lifted through the incision onto the draped abdominal wall. Then the uterus is closed with one layer of continuous vicryl suture. The abdomen is closed by a continuous suture of fascia, and widely spaced silk stitches of the skin. We sometimes use continuous suture of the skin. We do not close visceral and parietal peritoneum, recti muscles and subcutis. In our experience Misgav-Ladach method is 50% less time consuming, it reduces blood loss by about 250 ml. and allows for a much faster delivery of the fetus than Pfannenstiel method. The post operative outcome of the two methods is similar. Using the blunt preparation in the Joel-Cohen method causes less trauma and shortens convalescence time. We therefore recommend Misgav-Ladach method for cesarean section.

Hairy Slices: Evaluating the Perceptual Effectiveness of Cutting Plane Glyphs for 3D Vector Fields.

PubMed

Stevens, Andrew H; Butkiewicz, Thomas; Ware, Colin

2017-01-01

Three-dimensional vector fields are common datasets throughout the sciences. Visualizing these fields is inherently difficult due to issues such as visual clutter and self-occlusion. Cutting planes are often used to overcome these issues by presenting more manageable slices of data. The existing literature provides many techniques for visualizing the flow through these cutting planes; however, there is a lack of empirical studies focused on the underlying perceptual cues that make popular techniques successful. This paper presents a quantitative human factors study that evaluates static monoscopic depth and orientation cues in the context of cutting plane glyph designs for exploring and analyzing 3D flow fields. The goal of the study was to ascertain the relative effectiveness of various techniques for portraying the direction of flow through a cutting plane at a given point, and to identify the visual cues and combinations of cues involved, and how they contribute to accurate performance. It was found that increasing the dimensionality of line-based glyphs into tubular structures enhances their ability to convey orientation through shading, and that increasing their diameter intensifies this effect. These tube-based glyphs were also less sensitive to visual clutter issues at higher densities. Adding shadows to lines was also found to increase perception of flow direction. Implications of the experimental results are discussed and extrapolated into a number of guidelines for designing more perceptually effective glyphs for 3D vector field visualizations.

Porosity characterization for heterogeneous shales using integrated multiscale microscopy

NASA Astrophysics Data System (ADS)

Rassouli, F.; Andrew, M.; Zoback, M. D.

2016-12-01

Pore size distribution analysis plays a critical role in gas storage capacity and fluid transport characterization of shales. Study of the diverse distribution of pore size and structure in such low permeably rocks is withheld by the lack of tools to visualize the microstructural properties of shale rocks. In this paper we try to use multiple techniques to investigate the full pore size range in different sample scales. Modern imaging techniques are combined with routine analytical investigations (x-ray diffraction, thin section analysis and mercury porosimetry) to describe pore size distribution of shale samples from Haynesville formation in East Texas to generate a more holistic understanding of the porosity structure in shales, ranging from standard core plug down to nm scales. Standard 1" diameter core plug samples were first imaged using a Versa 3D x-ray microscope at lower resolutions. Then we pick several regions of interest (ROIs) with various micro-features (such as micro-cracks and high organic matters) in the rock samples to run higher resolution CT scans using a non-destructive interior tomography scans. After this step, we cut the samples and drill 5 mm diameter cores out of the selected ROIs. Then we rescan the samples to measure porosity distribution of the 5 mm cores. We repeat this step for samples with diameter of 1 mm being cut out of the 5 mm cores using a laser cutting machine. After comparing the pore structure and distribution of the samples measured form micro-CT analysis, we move to nano-scale imaging to capture the ultra-fine pores within the shale samples. At this stage, the diameter of the 1 mm samples will be milled down to 70 microns using the laser beam. We scan these samples in a nano-CT Ultra x-ray microscope and calculate the porosity of the samples by image segmentation methods. Finally, we use images collected from focused ion beam scanning electron microscopy (FIB-SEM) to be able to compare the results of porosity measurements from all different imaging techniques. These multi-scale characterization techniques are then compared with traditional analytical techniques such as Mercury Porosimetry.

Experimental Research and Mathematical Modeling of Parameters Effecting on Cutting Force and SurfaceRoughness in CNC Turning Process

NASA Astrophysics Data System (ADS)

Zeqiri, F.; Alkan, M.; Kaya, B.; Toros, S.

2018-01-01

In this paper, the effects of cutting parameters on cutting forces and surface roughness based on Taguchi experimental design method are determined. Taguchi L9 orthogonal array is used to investigate the effects of machining parameters. Optimal cutting conditions are determined using the signal/noise (S/N) ratio which is calculated by average surface roughness and cutting force. Using results of analysis, effects of parameters on both average surface roughness and cutting forces are calculated on Minitab 17 using ANOVA method. The material that was investigated is Inconel 625 steel for two cases with heat treatment and without heat treatment. The predicted and calculated values with measurement are very close to each other. Confirmation test of results showed that the Taguchi method was very successful in the optimization of machining parameters for maximum surface roughness and cutting forces in the CNC turning process.

Effect of Cut Quality on Hybrid Laser Arc Welding of Thick Section Steels

NASA Astrophysics Data System (ADS)

Farrokhi, F.; Nielsen, S. E.; Schmidt, R. H.; Pedersen, S. S.; Kristiansen, M.

From an industrial point of view, in a laser cutting-welding production chain, it is of great importance to know the influence of the attainable laser cut quality on the subsequent hybrid laser arc welding process. Many studies have been carried out in the literature to obtain lower surface roughness values on the laser cut edge. However, in practice, the cost and reliability of the cutting process is crucial and it does not always comply with obtaining the highest surface quality. In this study, a number of experiments on 25 mm steel plates were carried out to evaluate the influence of cut surface quality on the final quality of the subsequent hybrid laser welded joints. The different cut surfaces were obtained by different industrial cutting methods including laser cutting, abrasive water cutting, plasma cutting, and milling. It was found that the mentioned cutting methods could be used as preparation processes for the subsequent hybrid laser arc welding. However, cut quality could determine the choice of process parameters of the following hybrid laser arc welding.

[Histochemical stains for minerals by hematoxylin-lake method].

PubMed

Miyagawa, Makoto

2013-04-01

The present study was undertaken to establish the experimental animal model by histological staining methods for minerals. After intraperitoneal injections of minerals, precipitates deposited on the surface of the liver. Liver tissues were fixed in paraformaldehyde, embedded in paraffin and cut into thin sections which were used as minerals containing standard section. Several reagents for histological stains and spectrophotometry for minerals were applied in both test-tube experiments and stainings of tissue sections to test for minerals. Hematoxylin-lake was found of capable of staining minerals in tissue. A simple technique used was described for light microscopic detection of minerals.

Dew point measurement technique utilizing fiber cut reflection

NASA Astrophysics Data System (ADS)

Kostritskii, S. M.; Dikevich, A. A.; Korkishko, Yu. N.; Fedorov, V. A.

2009-05-01

The fiber optical dew point hygrometer based on change of reflection coefficient for fiber cut has been developed and examined. We proposed and verified the model of condensation detector functioning principle. Experimental frost point measurements on air with different frost points have been performed.

Computerized technique for recording board defect data

Treesearch

R. Bruce Anderson; R. Edward Thomas; Charles J. Gatchell; Neal D. Bennett; Neal D. Bennett

1993-01-01

A computerized technique for recording board defect data has been developed that is faster and more accurate than manual techniques. The lumber database generated by this technique is a necessary input to computer simulation models that estimate potential cutting yields from various lumber breakdown sequences. The technique allows collection of detailed information...

Role of failure-mechanism identification in accelerated testing

NASA Technical Reports Server (NTRS)

Hu, J. M.; Barker, D.; Dasgupta, A.; Arora, A.

1993-01-01

Accelerated life testing techniques provide a short-cut method to investigate the reliability of electronic devices with respect to certain dominant failure mechanisms that occur under normal operating conditions. However, accelerated tests have often been conducted without knowledge of the failure mechanisms and without ensuring that the test accelerated the same mechanism as that observed under normal operating conditions. This paper summarizes common failure mechanisms in electronic devices and packages and investigates possible failure mechanism shifting during accelerated testing.

Molecular assay to fraud identification of meat products.

PubMed

Doosti, Abbas; Ghasemi Dehkordi, Payam; Rahimi, Ebrahim

2014-01-01

Detection of species fraud in meat products is important for consumer protection and food industries. A molecular technique such as PCR method for detection of beef, sheep, pork, chicken, donkey, and horse meats in food products was established. The purpose of this study was to identification of fraud and adulteration in industrial meat products by PCR-RFLP assay in Iran. In present study, 224 meat products include 68 sausages, 48 frankfurters, 55 hamburgers, 33 hams and 20 cold cut meats were collected from different companies and food markets in Iran. Genomic DNA was extracted and PCR was performed for gene amplification of meat species using specific oligonucleotid primers. Raw meat samples are served as the positive control. For differentiation between donkey's and horse's meat, the mitochondrial DNA segment (cytochrome-b gene) was amplified and products were digested with AluI restriction enzyme. Results showed that 6 of 68 fermented sausages (8.82%), 4 of 48 frankfurters (8.33%), 4 of 55 hamburgers (7.27%), 2 of 33 hams (6.6%), and 1 of 20 cold cut meat (5%) were found to contain Haram (unlawful or prohibited) meat. These results indicate that 7.58% of the total samples were not containing Halal (lawful or permitted) meat and have another meat. These findings showed that molecular methods such as PCR and PCR-RFLP are potentially reliable techniques for detection of meat type in meat products for Halal authentication.

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.

Influence of microwave sterilization on the cutting capacity of carbide burs.

PubMed

Fais, Laiza Maria Grassi; Pinelli, Lígia Antunes Pereira; Adabo, Gelson Luis; Silva, Regina Helena Barbosa Tavares da; Marcelo, Caroline Canhizares; Guaglianoni, Dalton Geraldo

2009-01-01

This study compared the cutting capacity of carbide burs sterilized with microwaves and traditional sterilization methods. Sixty burs were divided into 5 groups according to the sterilization methods: dry heat (G1), autoclave (G2), microwave irradiation (G3), glutaraldehyde (G4) or control - no sterilization (G5). The burs were used to cut glass plates in a cutting machine set for twelve 2.5-min periods and, after each period, they were sterilized (except G5) following the protocol established for each group. The cutting capacity of the burs was determined by a weight-loss method. Data were analyzed statistically by Kruskal-Wallis and Dunn's test. The means of the cutting amount performed by each group after the 12 periods were G1 = 0.2167 +/- 0.0627 g; G2 = 0.2077 +/- 0.0231 g; G3 = 0.1980 +/- 0.0326 g; G4 = 0.1203 +/- 0.0459 g; G5 = 0.2642 +/- 0.0359 g. There were statistically significant differences among the groups (p<0.05); only dry heat sterilization was similar to the control. Sterilization by dry heat was the method that least affected the cutting capacity of the carbide burs and microwave sterilization was not better than traditional sterilization methods.

INFLUENCE OF MICROWAVE STERILIZATION ON THE CUTTING CAPACITY OF CARBIDE BURS

PubMed Central

Fais, Laiza Maria Grassi; Pinelli, Lígia Antunes Pereira; Adabo, Gelson Luis; da Silva, Regina Helena Barbosa Tavares; Marcelo, Caroline Canhizares; Guaglianoni, Dalton Geraldo

2009-01-01

Objective: This study compared the cutting capacity of carbide burs sterilized with microwaves and traditional sterilization methods. Material and Methods: Sixty burs were divided into 5 groups according to the sterilization methods: dry heat (G1), autoclave (G2), microwave irradiation (G3), glutaraldehyde (G4) or control – no sterilization (G5). The burs were used to cut glass plates in a cutting machine set for twelve 2.5-min periods and, after each period, they were sterilized (except G5) following the protocol established for each group. The cutting capacity of the burs was determined by a weight-loss method. Data were analyzed statistically by Kruskal-Wallis and Dunn's test. Results: The means of the cutting amount performed by each group after the 12 periods were G1 = 0.2167 ± 0.0627 g; G2 = 0.2077 ± 0.0231 g; G3 = 0.1980 ± 0.0326 g; G4 = 0.1203 ± 0.0459 g; G5 = 0.2642 ± 0.0359 g. There were statistically significant differences among the groups (p<0.05); only dry heat sterilization was similar to the control. Conclusion: Sterilization by dry heat was the method that least affected the cutting capacity of the carbide burs and microwave sterilization was not better than traditional sterilization methods. PMID:20027431

Comparison of preprocessing methods and storage times for touch DNA samples

PubMed Central

Dong, Hui; Wang, Jing; Zhang, Tao; Ge, Jian-ye; Dong, Ying-qiang; Sun, Qi-fan; Liu, Chao; Li, Cai-xia

2017-01-01

Aim To select appropriate preprocessing methods for different substrates by comparing the effects of four different preprocessing methods on touch DNA samples and to determine the effect of various storage times on the results of touch DNA sample analysis. Method Hand touch DNA samples were used to investigate the detection and inspection results of DNA on different substrates. Four preprocessing methods, including the direct cutting method, stubbing procedure, double swab technique, and vacuum cleaner method, were used in this study. DNA was extracted from mock samples with four different preprocessing methods. The best preprocess protocol determined from the study was further used to compare performance after various storage times. DNA extracted from all samples was quantified and amplified using standard procedures. Results The amounts of DNA and the number of alleles detected on the porous substrates were greater than those on the non-porous substrates. The performances of the four preprocessing methods varied with different substrates. The direct cutting method displayed advantages for porous substrates, and the vacuum cleaner method was advantageous for non-porous substrates. No significant degradation trend was observed as the storage times increased. Conclusion Different substrates require the use of different preprocessing method in order to obtain the highest DNA amount and allele number from touch DNA samples. This study provides a theoretical basis for explorations of touch DNA samples and may be used as a reference when dealing with touch DNA samples in case work. PMID:28252870

Study on Circular Complex viewed from Environmental Systems

NASA Astrophysics Data System (ADS)

Takeguchi, Tomoo; Adachi, Katsushige; Yoshikawa, Akira; Hiratsuka, Akira; Tsujino, Ryoji; Iguchi, Manabu

In machining processes, cutting fluids are generally used for cooling and lubricating workpieces at the point cutting. However, these fluids frequently include chlorine, sulfur, phosphorus, or other additives. The chemicals not only become a mist affecting the health of workers engaged in the processing but also make the workshop environment worse. In particular, the chlorine becomes one of the causes of global warming by treating waste oil under high temperature conditions. It is furthermore said that huge cost beyond the purchase cost of oil occurs and dioxins (carcinogen) usually exist in the waste oil. Therefore, an environmentally-friendly cooling-air cutting system is required from the standpoint of green manufacturing. This system has been noted as a technique to solve the issues against the environment mentioned above. In the cooling-air cutting processing, the amount of CO2 emission shows a low value compared with the dry cutting one which uses oil. It is therefore thought that the cooling-air cutting system is a very important processing technique as an environmental countermeasure. At present, in strictly economic and environmental situations, the compatibility of the betterment of production efficiency with the improvement of environment is a subject in the actual spot of a cut processing. This study deals with the test results of cooling-air drilling performance from the viewpoint of taking green manufacturing into account. The workpiece made of die steel SKDll was manufactured by the cooling-air drilling performance at a revolution of 840 rpm and a temperature of -20°C with a high-speed steel drill (SKH56). The results were compared with those for the dry cutting performance. The main results obtained in this study are as follows: 1) The tool life for cooling-air drilling performance was about 6 times as long as that for the dry cutting performance. 2) The chip temperature for cooling-air drilling was 220°C lower than that for the dry cutting performance.

The role of the implementation angle of cuttings of Phyllanthus sellowianus as a reference for a soil protection measure against surface erosion

NASA Astrophysics Data System (ADS)

Rauch, H. P.; Sutili, F. J.; Aschbacher, M.; Müller, B.

2009-04-01

Cutting plantation is a very common method of soil bioengineering techniques. The potential of vegetative reproduction is used to install a vegetation cover on eroded slopes to prevent surface erosion. The development of above and below biomass from parts of the stock plant in a very short time and the fast and easy propagation are one of the most important advantages of this soil bioengineering type. Several handbooks (Schiechtl, 1992; Florineth, 2004 and Zeh, 2007) suggest potential plants for vegetative reproduction and describe the procedure of plantation in detail. It is recommended that the cuttings are not driven vertically into the ground. A flat implementation angle guarantees a more uniform rooting of the cutting part driven into the soil, however there are no systematically investigations of the impact of the implementation angle on the biomass performance and consequently on the performance as a surface erosion protection measure. This paper shows results from field investigations focusing on the problem of the impact of the implementation angle of cuttings. In sum 75 specimens of the species of Phyllanthus sellowianus. The plant species was recommended as a native potential soil bioengineering plant by Sutili (s. Sutili, 2006). The cuttings were planted with an average length of 50 cm and diameter of 2 cm. The implementation angle differences between 90 (vertical) 45 and 10 degree. Two months after plantation all plants were excavated and the relevant plant data sets were collected in order to analyse the biomass performance. The field investigations are part of an integrated research project of the University of Natural Resources and Applied Life Sciences, Vienna and the Federal University of Santa Maria, Rio Grande do Sul - Brazil.

Relative abundance and species richness of cerambycid beetles in partial cut and uncut bottomland hardwood forests

USGS Publications Warehouse

Newell, P.; King, S.

2009-01-01

Partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife. However, partial cutting may or may not benefit species dependent on deadwood; harvesting can supplement coarse woody debris in the form of logging slash, but standing dead trees may be targeted for removal. We sampled cerambycid beetles during the spring and summer of 2006 and 2007 with canopy malaise traps in 1- and 2-year-old partial cut and uncut bottomland hardwood forests of Louisiana. We captured a total of 4195 cerambycid beetles representing 65 species. Relative abundance was higher in recent partial cuts than in uncut controls and with more dead trees in a plot. Total species richness and species composition were not different between treatments. The results suggest partial cuts with logging slash left on site increase the abundance of cerambycid beetles in the first few years after partial cutting and that both partial cuts and uncut forest should be included in the bottomland hardwood forest landscape.

Identification of the critical depth-of-cut through a 2D image of the cutting region resulting from taper cutting of brittle materials

NASA Astrophysics Data System (ADS)

Gu, Wen; Zhu, Zhiwei; Zhu, Wu-Le; Lu, Leyao; To, Suet; Xiao, Gaobo

2018-05-01

An automatic identification method for obtaining the critical depth-of-cut (DoC) of brittle materials with nanometric accuracy and sub-nanometric uncertainty is proposed in this paper. With this method, a two-dimensional (2D) microscopic image of the taper cutting region is captured and further processed by image analysis to extract the margin of generated micro-cracks in the imaging plane. Meanwhile, an analytical model is formulated to describe the theoretical curve of the projected cutting points on the imaging plane with respect to a specified DoC during the whole cutting process. By adopting differential evolution algorithm-based minimization, the critical DoC can be identified by minimizing the deviation between the extracted margin and the theoretical curve. The proposed method is demonstrated through both numerical simulation and experimental analysis. Compared with conventional 2D- and 3D-microscopic-image-based methods, determination of the critical DoC in this study uses the envelope profile rather than the onset point of the generated cracks, providing a more objective approach with smaller uncertainty.

Custom-Made Finger Guard to Prevent Wire-Stick Injury to the Operator's Finger while Performing Intermaxillary Fixation.

PubMed

Kumaresan, Ramesh; Ponnusami, Karthikeyan; Karthikeyan, Priyadarshini

2014-12-01

The treatment of maxillofacial fractures involves different methods from bandages and splinting to methods of open reduction and internal fixation and usually requires control of the dental occlusion with the help of intermaxillary fixation (IMF). Different wiring techniques have been used to aid in IMF including placement of custom-made arch bars, eyelet etc. However, these wiring techniques are with a constant danger of trauma to the surgeon's fingers by their sharp ends. Though there exist a variety of commercially available barrier products and customized techniques to prevent wire-stick injury, cost factor, touch sensitivity, and comfort aspect restrain their acquirement and exploit. This technical note describes the construction of a simple and economical finger guard made of soft thermoplastic material that provides an added protection to fingers from wire-stick type injuries, and its flexible nature permits a comfortable finger flexion movement and acceptable touch sensitivity. This is a simple, economical, reusable puncture, and cut-resistance figure guard by which we can avoid wire-stick type injury to the operator's fingers during wiring technique.

Genome engineering in ornamental plants: Current status and future prospects.

PubMed

Kishi-Kaboshi, Mitsuko; Aida, Ryutaro; Sasaki, Katsutomo

2018-03-13

Ornamental plants, like roses, carnations, and chrysanthemums, are economically important and are sold all over the world. In addition, numerous cut and garden flowers add colors to homes and gardens. Various strategies of plant breeding have been employed to improve traits of many ornamental plants. These approaches span from conventional techniques, such as crossbreeding and mutation breeding, to genetically modified plants. Recently, genome editing has become available as an efficient means for modifying traits in plant species. Genome editing technology is useful for genetic analysis and is poised to become a common breeding method for ornamental plants. In this review, we summarize the benefits and limitations of conventional breeding techniques and genome editing methods and discuss their future potential to accelerate the rate breeding programs in ornamental plants. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Line-scan spatially offset Raman spectroscopy for inspecting subsurface food safety and quality

NASA Astrophysics Data System (ADS)

Qin, Jianwei; Chao, Kuanglin; Kim, Moon S.

2016-05-01

This paper presented a method for subsurface food inspection using a newly developed line-scan spatially offset Raman spectroscopy (SORS) technique. A 785 nm laser was used as a Raman excitation source. The line-shape SORS data was collected in a wavenumber range of 0-2815 cm-1 using a detection module consisting of an imaging spectrograph and a CCD camera. A layered sample, which was created by placing a plastic sheet cut from the original container on top of cane sugar, was used to test the capability for subsurface food inspection. A whole set of SORS data was acquired in an offset range of 0-36 mm (two sides of the laser) with a spatial interval of 0.07 mm. Raman spectrum from the cane sugar under the plastic sheet was resolved using self-modeling mixture analysis algorithms, demonstrating the potential of the technique for authenticating foods and ingredients through packaging. The line-scan SORS measurement technique provides a new method for subsurface inspection of food safety and quality.

An Investigation of Undefined Cut Scores with the Hofstee Standard-Setting Method

ERIC Educational Resources Information Center

Wyse, Adam E.; Babcock, Ben

2017-01-01

This article provides an overview of the Hofstee standard-setting method and illustrates several situations where the Hofstee method will produce undefined cut scores. The situations where the cut scores will be undefined involve cases where the line segment derived from the Hofstee ratings does not intersect the score distribution curve based on…

The Objective Borderline method (OBM): a probability-based model for setting up an objective pass/fail cut-off score in medical programme assessments.

PubMed

Shulruf, Boaz; Turner, Rolf; Poole, Phillippa; Wilkinson, Tim

2013-05-01

The decision to pass or fail a medical student is a 'high stakes' one. The aim of this study is to introduce and demonstrate the feasibility and practicality of a new objective standard-setting method for determining the pass/fail cut-off score from borderline grades. Three methods for setting up pass/fail cut-off scores were compared: the Regression Method, the Borderline Group Method, and the new Objective Borderline Method (OBM). Using Year 5 students' OSCE results from one medical school we established the pass/fail cut-off scores by the abovementioned three methods. The comparison indicated that the pass/fail cut-off scores generated by the OBM were similar to those generated by the more established methods (0.840 ≤ r ≤ 0.998; p < .0001). Based on theoretical and empirical analysis, we suggest that the OBM has advantages over existing methods in that it combines objectivity, realism, robust empirical basis and, no less importantly, is simple to use.

Optimization of CO2 laser cutting parameters on Austenitic type Stainless steel sheet

NASA Astrophysics Data System (ADS)

Parthiban, A.; Sathish, S.; Chandrasekaran, M.; Ravikumar, R.

2017-03-01

Thin AISI 316L stainless steel sheet widely used in sheet metal processing industries for specific applications. CO2 laser cutting is one of the most popular sheet metal cutting processes for cutting of sheets in different profile. In present work various cutting parameters such as laser power (2000 watts-4000 watts), cutting speed (3500mm/min - 5500 mm/min) and assist gas pressure (0.7 Mpa-0.9Mpa) for cutting of AISI 316L 2mm thickness stainless sheet. This experimentation was conducted based on Box-Behenken design. The aim of this work is to develop a mathematical model kerf width for straight and curved profile through response surface methodology. The developed mathematical models for straight and curved profile have been compared. The Quadratic models have the best agreement with experimental data, and also the shape of the profile a substantial role in achieving to minimize the kerf width. Finally the numerical optimization technique has been used to find out best optimum laser cutting parameter for both straight and curved profile cut.

Fibers comprised of epitaxially grown single-wall carbon nanotubes, and a method for added catalyst and continuous growth at the tip

DOEpatents

Kittrell, W. Carter; Wang, Yuhuang; Kim, Myung Jong; Hauge, Robert H.; Smalley, Richard E.; Marek leg, Irene Morin

2010-06-01

The present invention is directed to fibers of epitaxially grown single-wall carbon nanotubes (SWNTs) and methods of making same. Such methods generally comprise the steps of: (a) providing a spun SWNT fiber; (b) cutting the fiber substantially perpendicular to the fiber axis to yield a cut fiber; (c) etching the cut fiber at its end with a plasma to yield an etched cut fiber; (d) depositing metal catalyst on the etched cut fiber end to form a continuous SWNT fiber precursor; and (e) introducing feedstock gases under SWNT growth conditions to grow the continuous SWNT fiber precursor into a continuous SWNT fiber.

Transfer of Pathogens from Cantaloupe Rind to Preparation Surfaces and Edible Tissue as a Function of Cutting Method.

PubMed

Shearer, Adrienne E H; LeStrange, Kyle; Castañeda Saldaña, Rafael; Kniel, Kalmia E

2016-05-01

Whole and cut cantaloupes have been implicated as vehicles in foodborne illness outbreaks of norovirus, salmonellosis, and listeriosis. Preparation methods that minimize pathogen transfer from external surfaces to the edible tissue are needed. Two preparation methods were compared for the transfer of Listeria monocytogenes, Salmonella enterica serovar Typhimurium LT2, murine norovirus, and Tulane virus from inoculated cantaloupe rinds to edible tissue and preparation surfaces. For the first method, cantaloupes were cut into eighths, and edible tissue was separated from the rind and cubed with the same knife used to open the cantaloupes. For the second method, cantaloupes were scored with a knife around the circumference sufficient to allow manual separation of the cantaloupes into halves. Edible tissue was scooped with a spoon and did not contact the preparation surface touched by the rind. Bacteria and virus were recovered from the rinds, preparation surfaces, and edible tissue and enumerated by culture methods and reverse transcription, quantitative PCR, respectively. Standard plate counts were determined throughout refrigerated storage of cantaloupe tissue. Cut method 2 yielded approximately 1 log lower recovery of L. monocytogenes and Salmonella Typhimurium from edible tissue, depending on the medium in which the bacteria were inoculated. A slight reduction was observed in murine norovirus recovered from edible tissue by cut method 2. The Tulane virus was detected in approximately half of the sampled cantaloupe tissue and only at very low levels. Aerobic mesophilic colony counts were lower through day 6 of storage for buffered peptone water-inoculated cantaloupes prepared by cut method 2. No differences were observed in environmental contamination as a function of cutting method. Although small reductions in contamination of edible tissue were observed for cut method 2, the extent of microbial transfer underscores the importance of preventing contamination of whole cantaloupes.

Research on cutting path optimization of sheet metal parts based on ant colony algorithm

NASA Astrophysics Data System (ADS)

Wu, Z. Y.; Ling, H.; Li, L.; Wu, L. H.; Liu, N. B.

2017-09-01

In view of the disadvantages of the current cutting path optimization methods of sheet metal parts, a new method based on ant colony algorithm was proposed in this paper. The cutting path optimization problem of sheet metal parts was taken as the research object. The essence and optimization goal of the optimization problem were presented. The traditional serial cutting constraint rule was improved. The cutting constraint rule with cross cutting was proposed. The contour lines of parts were discretized and the mathematical model of cutting path optimization was established. Thus the problem was converted into the selection problem of contour lines of parts. Ant colony algorithm was used to solve the problem. The principle and steps of the algorithm were analyzed.

Arthroscopic Double-Row Transosseous Equivalent Rotator Cuff Repair with a Knotless Self-Reinforcing Technique.

PubMed

Mook, William R; Greenspoon, Joshua A; Millett, Peter J

2016-01-01

Rotator cuff tears are a significant cause of shoulder morbidity. Surgical techniques for repair have evolved to optimize the biologic and mechanical variables critical to tendon healing. Double-row repairs have demonstrated superior biomechanical advantages to a single-row. The preferred technique for rotator cuff repair of the senior author was reviewed and described in a step by step fashion. The final construct is a knotless double row transosseous equivalent construct. The described technique includes the advantages of a double-row construct while also offering self reinforcement, decreased risk of suture cut through, decreased risk of medial row overtensioning and tissue strangulation, improved vascularity, the efficiency of a knotless system, and no increased risk for subacromial impingement from the burden of suture knots. Arthroscopic knotless double row rotator cuff repair is a safe and effective method to repair rotator cuff tears.

Soil zymography - A novel technique for mapping enzyme activity in the rhizosphere

NASA Astrophysics Data System (ADS)

Spohn, Marie

2014-05-01

The effect plant roots on microbial activity in soil at the millimeter scale is poorly understood. One reason for this is that spatially explicit methods for the study of microbial activity in soil are limited. Here we present a quantitative in situ technique for mapping the distribution of exoenzymes in soil along with some results about the effects of roots on exoenzyme activity in soil. In the first study we showed that both acid and alkaline phosphatase activity were up to 5.4-times larger in the rhizosphere of Lupinus albus than in the bulk soil. While acid phosphatase activity (produced by roots and microorganisms) was closely associated with roots, alkaline phosphatase activity (produced only by microorganisms) was more widely distributed, leading to a 2.5-times larger area of activity of alkaline than of acid phosphatase. These results indicate a spatial differentiation of different ecophysiological groups of organic phosphorus mineralizing organisms in the rhizosphere which might alleviate a potential competition for phosphorus between them. In a second study cellulase, chitinase and phosphatase activities were analyzed in the presence of living Lupinus polyphyllus roots and dead/dying roots (in the same soils 10, 20 and 30 days after cutting the L. polyphyllus shoots). The activity of all three enzymes was 9.0 to 13.9-times higher at the living roots compared to the bulk soil. Microhotspots of cellulase, chitinase and phosphatase activity in the soil were found up to 60 mm away from the living roots. 10 days after shoot cutting, the areas of high activities of cellulase and phosphatase activity were extend up to 55 mm away from the next root, while the extension of the area of chitinase activity did not change significantly. At the root, cellulase and chitinase activity increased first at the root tips after shoot cutting and showed maximal activity 20 days after shoot cutting. The number and activity of microhotspots of chitinase activity was maximal 10 days after shoot cutting and decreased thereafter. In conclusion, the study showed that fresh root detritus stimulates enzyme activities much stronger than living roots, probably because of the high pulse input of C and N from dying roots compared to slow continuous release of rhizodeposits. Taken together, soil zymography is a very promising novel technique to gain insights the effects of roots on the spatial and temporal dynamic of exoenzyme activity in soil. References Spohn, M., Carminati, A., Kuzyakov, Y. (2013). Zymography - A novel in situ method for mapping distribution of enzyme activity in soil. Soil Biology and Biochemistry 58, 275-280. Spohn, M., Kuzyakov, Y. (2013): Distribution of microbial- and root- derived phosphatase activities in the rhizosphere depending on P availability and C allocation - Coupling soil zymography with 14C imaging. Soil Biology and Biochemistry 67, 106-113. Spohn, M., Kuzyakov, Y. (accepted): Spatial and temporal dynamics of hotspots of enzyme activity as affected by living and dead roots - A soil zymography analysis. Plant and Soil

A review of technology and safety aspects of erbium lasers in dentistry.

PubMed

Clarkson, D M

2001-01-01

This article reviews aspects of the probable mechanisms used by erbium dental lasers for cutting dentine and enamel, describes key issues of the risk of temperature elevation and speed of cutting relative to conventional techniques and looks at issues concerned with the safety of lasers.

Orthogonal cutting of cancellous bone with application to the harvesting of bone autograft.

PubMed

Malak, Sharif F F; Anderson, Iain A

2008-07-01

Autogenous bone graft harvesting results in cell death within the graft and trauma at the donor site. The latter can be mitigated by using minimally invasive tools and techniques, while cell morbidity may be reduced by improving cutter design and cutting parameters. We have performed orthogonal cutting experiments on bovine cancellous bone samples, to gain a basic understanding of the cutting mechanism and to determine design guidelines for tooling. Measurements were performed at cutting speeds from 11.2 to 5000 mm/min, with tool rake angles of 23 degrees, 45 degrees and 60 degrees, and depths of cut in the range of 0.1-3.0 mm. Horizontal and vertical cutting forces were measured, and the chip formation process video recorded. Continuous chip formation was observed for rake angles of 45 degrees and 60 degrees , and depths of cut greater than 0.8 mm. Chip formation for depths of cut greater than 1.0 mm was accompanied by bone marrow extruding out of the free surfaces and away from the rake face. Specific cutting energies decreased with increasing rake angle, increasing depth of cut and increasing cutting speed. Our orthogonal cutting experiments showed that a rake angle of 60 degrees and a depth of cut of 1mm, will avoid excessive fragmentation, keep specific cutting energy low and promote bone marrow extrusion, which may be beneficial for cell survival. We demonstrate how drill bit clearance angle and feed rate can be calculated facilitating a 1mm depth of cut.

[Comparisons of different methods for virus-elimination of edible fungi].

PubMed

Zhang, Chao-hui; Liu, Ying-miao; Qi, Yuan-cheng; Gao, Yu-qian; Shen, Jin-wen; Qiu, Li-you

2010-05-01

Four dsRNA bands were extracted from Pleurotus ostreatus TD300 by the dsRNA isolation technique with sizes of 8.2 kb, 2.5 kb, 2.1 kb, and 1.1 kb, respectively. Four virus-eliminated methods, i. e. hyphal tips cut (HTC), protoplast regeneration (PR), single spore hybridization (SSH), and frozen and lyophilized (FL), were applied to prepare virus-eliminated strains, and one virus-eliminated strain was selected for each virus-elimination method. The virus-eliminated strains were named as HTC8, PR15, FL01, and SSH11, respectively. There were low concentration of 8.2 kb dsRNA remained in HTC8, as well as low concentration of 8.2 kb and 2.5 kb dsRNA remained in FL01. However, no dsRNA remained in PR15 and SSH11. The hyphal growth rate and laccase activity of the virus-eliminated strains increased, especially HTC8 and PR15, whose hyphal growth rate was higher by 22.73% and 18.18%, and laccase activities higher by 145.83% and 134.38% than that of the original strain, respectively. The conclusion is that hyphal tips cut and protoplast regeneration are suitable to prepare virus-eliminated strains of edible fungi.

New developments in surface technology and prototyping

NASA Astrophysics Data System (ADS)

Himmer, Thomas; Beyer, Eckhard

2003-03-01

Novel lightweight applications in the automotive and aircraft industries require advanced materials and techniques for surface protection as well as direct and rapid manufacturing of the related components and tools. The manufacturing processes presented in this paper are based on multiple additive and subtractive technologies such as laser cutting, laser welding, direct laser metal deposition, laser/plasma hybrid spraying technique or CNC milling. The process chain is similar to layer-based Rapid Prototyping Techniques. In the first step, the 3D CAD geometry is sliced into layers by a specially developed software. These slices are cut by high speed laser cutting and then joined together. In this way laminated tools or parts are built. To improve surface quality and to increase wear resistance a CNC machining center is used. The system consists of a CNC milling machine, in which a 3 kW Nd:YAG laser, a coaxial powder nozzle and a digitizing system are integrated. Using a new laser/plasma hybrid spraying technique, coatings can be deposited onto parts for surface protection. The layers show a low porosity and high adhesion strength, the thickness is up to 0.3 mm, and the lower effort for preliminary surface preparation reduces time and costs of the whole process.

Apparatus and method for cutting soft materials, especially meat

DOEpatents

Spletzer, Barry L.; Callow, Diane S.; Jones, James F.; Kuehl, Michael A.; Shaw, Dick L.; Scalia, Barbara J.

2005-10-18

An apparatus and method for cutting soft materials such as meat. Two or more spirally mounted helical blades are situated between two supports, and the supports are mounted to a shank. The shank is rotated to impart rotary action to the spiral shear blades, and the entire device may be used to perform various cutting operations. The distal or bottom one of the supports may also be a cutting blade, and a number of versions of bottom cutting blades are useable in the practice of the invention.

Non-Exposure, Device-Assisted Endoscopic Full-thickness Resection.

PubMed

Bauder, Markus; Schmidt, Arthur; Caca, Karel

2016-04-01

Recent developments have expanded the frontier of interventional endoscopy toward more extended resections following surgical principles. This article presents two new device-assisted techniques for endoscopic full-thickness resection in the upper and lower gastrointestinal tract. Both methods are nonexposure techniques avoiding exposure of gastrointestinal contents to the peritoneal cavity by a "close first-cut later" principle. The full-thickness resection device is a novel over-the-scope device designed for clip-assisted full-thickness resection of colorectal lesions. Endoscopic full-thickness resection of gastric subepithelial tumors can be performed after placing transmural sutures underneath the tumor with a suturing device originally designed for endoscopic antireflux therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Deformation-based augmented reality for hepatic surgery.

PubMed

Haouchine, Nazim; Dequidt, Jérémie; Berger, Marie-Odile; Cotin, Stéphane

2013-01-01

In this paper we introduce a method for augmenting the laparoscopic view during hepatic tumor resection. Using augmented reality techniques, vessels, tumors and cutting planes computed from pre-operative data can be overlaid onto the laparoscopic video. Compared to current techniques, which are limited to a rigid registration of the pre-operative liver anatomy with the intra-operative image, we propose a real-time, physics-based, non-rigid registration. The main strength of our approach is that the deformable model can also be used to regularize the data extracted from the computer vision algorithms. We show preliminary results on a video sequence which clearly highlights the interest of using physics-based model for elastic registration.

Beyond the Snapshot.

ERIC Educational Resources Information Center

Smith, Lloyd

1979-01-01

Presents some inventive darkroom techniques which can lead students to new interests in designing creative images. These techniques include easel manipulation, image blending, paper negatives, vignette, vaseline smear, cut strip, flop negative, or combinations of these. Each technique is illustrated by a student photograph. (Author/SJL)

Method for making thick and/or thin film

DOEpatents

Pham, Ai Quoc; Glass, Robert S.

2004-11-02

A method to make thick or thin films a very low cost. The method is generally similar to the conventional tape casting techniques while being more flexible and versatile. The invention involves preparing a slip (solution) of desired material and including solvents such as ethanol and an appropriate dispersant to prevent agglomeration. The slip is then sprayed on a substrate to be coated using an atomizer which spreads the slip in a fine mist. Upon hitting the substrate, the solvent evaporates, leaving a green tape containing the powder and other additives, whereafter the tape may be punctured, cut, and heated for the desired application. The tape thickness can vary from about 1 .mu.m upward.

Sampling methods in archaeomagnetic dating: A comparison using case studies from Wörterberg, Eisenerz and Gams Valley (Austria)

NASA Astrophysics Data System (ADS)

Trapanese, A.; Batt, C. M.; Schnepp, E.

The aim of this research was to review the relative merits of different methods of taking samples for archaeomagnetic dating. To allow different methods to be investigated, two archaeological structures and one modern fireplace were sampled in Austria. On each structure a variety of sampling methods were used: the tube and disc techniques of Clark et al. (Clark, A.J., Tarling, D.H., Noel, M., 1988. Developments in archaeomagnetic dating in Great Britain. Journal of Archaeological Science 15, 645-667), the drill core technique, the mould plastered hand block method of Thellier, and a modification of it. All samples were oriented with a magnetic compass and sun compass, where weather conditions allowed. Approximately 12 discs, tubes, drill cores or plaster hand blocks were collected from each structure, with one mould plaster hand block being collected and cut into specimens. The natural remanent magnetisation (NRM) of the samples was measured and stepwise alternating field (AF) or thermal demagnetisation was applied. Samples were measured either in the UK or in Austria, which allowed the comparison of results between magnetometers with different sensitivity. The tubes and plastered hand block specimens showed good agreement in directional results, and the samples obtained showed good stability. The discs proved to be unreliable as both NRM and the characteristic remanent magnetisation (ChRM) distribution were very scattered. The failure of some methods may be related to the suitability of the material sampled, for example if it was disturbed before sampling, had been insufficiently heated or did not contain appropriate magnetic minerals to retain a remanent magnetisation. Caution is also recommended for laboratory procedures as the cutting of poorly consolidated specimens may disturb the material and therefore the remanent magnetisation. Criteria and guidelines were established to aid researchers in selecting the most appropriate method for a particular archaeological structure.

Plasma-Spray Metal Coating On Foam

NASA Technical Reports Server (NTRS)

Cranston, J.

1994-01-01

Molds, forms, and other substrates made of foams coated with metals by plasma spraying. Foam might be ceramic, carbon, metallic, organic, or inorganic. After coat applied by plasma spraying, foam left intact or removed by acid leaching, conventional machining, water-jet cutting, or another suitable technique. Cores or vessels made of various foam materials plasma-coated with metals according to method useful as thermally insulating containers for foods, liquids, or gases, or as mandrels for making composite-material (matrix/fiber) parts, or making thermally insulating firewalls in automobiles.

Multiobjective fuzzy stochastic linear programming problems with inexact probability distribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamadameen, Abdulqader Othman; Zainuddin, Zaitul Marlizawati

This study deals with multiobjective fuzzy stochastic linear programming problems with uncertainty probability distribution which are defined as fuzzy assertions by ambiguous experts. The problem formulation has been presented and the two solutions strategies are; the fuzzy transformation via ranking function and the stochastic transformation when α{sup –}. cut technique and linguistic hedges are used in the uncertainty probability distribution. The development of Sen’s method is employed to find a compromise solution, supported by illustrative numerical example.

Optical laser systems at the Linac Coherent Light Source

DOE PAGES

Minitti, Michael P.; Robinson, Joseph S.; Coffee, Ryan N.; ...

2015-04-22

Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS.

Spherical thin-shell wormholes and modified Chaplygin gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharif, M.; Azam, M., E-mail: msharif.math@pu.edu.pk, E-mail: azammath@gmail.com

2013-05-01

The purpose of this paper is to construct spherical thin-shell wormhole solutions through cut and paste technique and investigate the stability of these solutions in the vicinity of modified Chaplygin gas. The Darmois-Israel formalism is used to formulate the stresses of the surface concentrating the exotic matter. We explore the stability of the wormhole solutions by using the standard potential method. We conclude that there exist more stable as well as unstable solutions than the previous study with generalized Chaplygin gas [19].

Knowledge acquisition for medical diagnosis using collective intelligence.

PubMed

Hernández-Chan, G; Rodríguez-González, A; Alor-Hernández, G; Gómez-Berbís, J M; Mayer-Pujadas, M A; Posada-Gómez, R

2012-11-01

The wisdom of the crowds (WOC) is the process of taking into account the collective opinion of a group of individuals rather than a single expert to answer a question. Based on this assumption, the use of processes based on WOC techniques to collect new biomedical knowledge represents a challenging and cutting-edge trend on biomedical knowledge acquisition. The work presented in this paper shows a new schema to collect diagnosis information in Diagnosis Decision Support Systems (DDSS) based on collective intelligence and consensus methods.

Novel method for fabrication of monolithic multi-cavity molds and wafer optics

NASA Astrophysics Data System (ADS)

Wielandts, Marc; Wielandts, Remi

2015-10-01

One lens at a time on axis diamond turning or grinding of lens arrays with a large number of lenses is conventionally impractical because of the difficulties to shift and balance the substrate for each lens position. A novel method for automatic indexing was developed. This method uses an innovative mechatronics tooling (patent pending) that allows dynamic indexing at constant work spindle speed for maximum productivity and thermal stability of the work spindle while the balancing condition is maintained. In this paper we shall compare the machining capabilities of this method to free-form machining techniques, discuss about the main issues, present the concept and design of the working prototype and specific test bed, and present the results of the first cutting tests.

SAR-based change detection using hypothesis testing and Markov random field modelling

NASA Astrophysics Data System (ADS)

Cao, W.; Martinis, S.

2015-04-01

The objective of this study is to automatically detect changed areas caused by natural disasters from bi-temporal co-registered and calibrated TerraSAR-X data. The technique in this paper consists of two steps: Firstly, an automatic coarse detection step is applied based on a statistical hypothesis test for initializing the classification. The original analytical formula as proposed in the constant false alarm rate (CFAR) edge detector is reviewed and rewritten in a compact form of the incomplete beta function, which is a builtin routine in commercial scientific software such as MATLAB and IDL. Secondly, a post-classification step is introduced to optimize the noisy classification result in the previous step. Generally, an optimization problem can be formulated as a Markov random field (MRF) on which the quality of a classification is measured by an energy function. The optimal classification based on the MRF is related to the lowest energy value. Previous studies provide methods for the optimization problem using MRFs, such as the iterated conditional modes (ICM) algorithm. Recently, a novel algorithm was presented based on graph-cut theory. This method transforms a MRF to an equivalent graph and solves the optimization problem by a max-flow/min-cut algorithm on the graph. In this study this graph-cut algorithm is applied iteratively to improve the coarse classification. At each iteration the parameters of the energy function for the current classification are set by the logarithmic probability density function (PDF). The relevant parameters are estimated by the method of logarithmic cumulants (MoLC). Experiments are performed using two flood events in Germany and Australia in 2011 and a forest fire on La Palma in 2009 using pre- and post-event TerraSAR-X data. The results show convincing coarse classifications and considerable improvement by the graph-cut post-classification step.

Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menapace, J A; Schaffers, K I; Bayramian, A J

2007-10-09

Ti:sapphire has become the premier lasing medium material for use in solid-state femtosecond high-peak power laser systems because of its wide wavelength tuning range. With a tuneable range from 680 to 1100 nm, peaking at 800 nm, Ti:sapphire lasing crystals can easily be tuned to the required pump wavelength and provide very high pump brightness due to their good beam quality and high output power of typically several watts. Femtosecond lasers are used for precision cutting and machining of materials ranging from steel to tooth enamel to delicate heart tissue and high explosives. These ultra-short pulses are too brief tomore » transfer heat or shock to the material being cut, which means that cutting, drilling, and machining occur with virtually no damage to surrounding material. Furthermore, these lasers can cut with high precision, making hairline cuts of less than 100 microns in thick materials along a computer-generated path. Extension of laser output to higher energies is limited by the size of the amplification medium. Yields of high quality large diameter crystals have been constrained by lattice distortions that may appear in the boule limiting the usable area from which high quality optics can be harvested. Lattice distortions affect the transmitted wavefront of these optics which ultimately limits the high-end power output and efficiency of the laser system, particularly when operated in multi-pass mode. To make matters even more complicated, Ti:sapphire is extremely hard (Mohs hardness of 9 with diamond being 10) which makes it extremely difficult to accurately polish using conventional methods without subsurface damage or significant wavefront error. In this presentation, we demonstrate for the first time that Magnetorheological finishing (MRF) can be used to compensate for the lattice distortions in Ti:sapphire by perturbing the transmitted wavefront. The advanced MRF techniques developed allow for precise polishing of the optical inverse of lattice distortions with magnitudes of about 70 nm in optical path difference onto one or both of the optical surfaces to produce high quality optics from otherwise unusable Ti:sapphire crystals. The techniques include interferometric, software, and machine modifications to precisely locate and polish sub-millimeter sites onto the optical surfaces that can not be polished into the optics conventionally. This work may allow extension of Ti:sapphire based systems to peak powers well beyond one petawatt.« less

Identifying self-interstitials of bcc and fcc crystals in molecular dynamics

NASA Astrophysics Data System (ADS)

Bukkuru, S.; Bhardwaj, U.; Warrier, M.; Rao, A. D. P.; Valsakumar, M. C.

2017-02-01

Identification of self-interstitials in molecular dynamics (MD) simulations is of critical importance. There exist several criteria for identifying the self-interstitial. Most of the existing methods use an assumed cut-off value for the displacement of an atom from its lattice position to identify the self-interstitial. The results obtained are affected by the chosen cut-off value. Moreover, these chosen cut-off values are independent of temperature. We have developed a novel unsupervised learning algorithm called Max-Space Clustering (MSC) to identify an appropriate cut-off value and its dependence on temperature. This method is compared with some widely used methods such as effective sphere (ES) method and nearest neighbor sphere (NNS) method. The cut-off radius obtained using our method shows a linear variation with temperature. The value of cut-off radius and its temperature dependence is derived for five bcc (Cr, Fe, Mo, Nb, W) and six fcc (Ag, Au, Cu, Ni, Pd, Pt) crystals. It is seen that the ratio of the cut-off values "r" to the lattice constant "a" lies between 0.23 and 0.3 at 300 K and this ratio is on an average smaller for the fcc crystals. Collision cascade simulations are carried out for Primary knock-on Atom (PKA) energies of 5 keV in Fe (at 300 K and 1000 K) and W (at 300 K and 2500 K) and the results are compared using the various methods.

Experimental and histological investigations of the bone using two different oscillating osteotomy techniques compared with conventional rotary osteotomy.

PubMed

Heinemann, Friedhelm; Hasan, Istabrak; Kunert-Keil, Christiane; Götz, Werner; Gedrange, Tomas; Spassov, Alexander; Schweppe, Janine; Gredes, Tomasz

2012-03-20

Over the past decade, coinciding with the appearance of a number of new ultrasonic surgical devices, there has been a marked increase in interest in the use of ultrasound in oral surgery and implantology as alternative osteotomy method. The aim of this study was the comparison of the effect of osteotomies performed using ultrasonic surgery (Piezosurgery(®)), sonic surgery SONICflex(®) and the conventional bur method on the heat generation within the bone underneath the osteotomy and light-microscopy observations of the bone at different cutting positions in porcine mandibular segments. It was found that the average heat generated by SONICflex(®) sonic device was close to that by conventional rotary bur (1.54-2.29°C), whereas Piezosurgery(®) showed a high generated heat up to 18.17°C. Histological investigations of the bone matrix adjacent to the defect radius showed intact osteocytes with all three instruments and similar wide damage diameter at the bottom region. SONICflex(®) showed smooth cutting surfaces with minimal damage in the upper defect zone. Finally, presented results showed that sonic surgery performed with SONICflex(®) is an alternative osteotomy method and can be used as an alternative to the conventional bur method. Copyright © 2011 Elsevier GmbH. All rights reserved.

Endoscopic removal of over-the-scope clips: Clinical experience with a bipolar cutting device

PubMed Central

Meier, Benjamin; Caca, Karel; Schmidt, Arthur

2016-01-01

Background Over-the-scope clips (OTSCs) are increasingly used for the closure of perforations/fistulae, hemostasis and endoscopic full-thickness resection (FTRD system). When OTSC-associated complications occur or re-therapy at the OTSC site is needed, OTSC removal may be indicated. An experimental study in an animal model and a case series have shown good results for OTSC removal with a bipolar cutting device. We present a larger clinical study using this device. Methods Data of all consecutive patients with indication for OTSC removal were collected and analyzed retrospectively. OTSCs were cut at two opposing sites using a bipolar grasping device to apply short direct current impulses. OTSC fragments were extracted with a standard forceps and a cap at the tip of the endoscope to avoid tissue damage. Results Between December 2012 and February 2016 a total of 42 OTSC removals in the upper (n = 25) and lower (n = 17) gastrointestinal tract have been performed at our department. Overall technical success, defined as cutting the OTSC at two opposing sites and extraction of both fragments, was achieved in 92.9% (39/42) of all cases. Successful fragmentation of the OTSC was achieved in 97.6% (41/42). Minor bleedings were rare and could be managed endoscopically in all cases. There were no perforations and no major or delayed bleedings. Conclusion Endoscopic OTSC removal with a bipolar cutting device is feasible, effective and safe. This technique can be applied in the upper and lower gastrointestinal tract. PMID:28588877

Measurement of total acid number (TAN) and TAN boiling point distribution in petroleum products by electrospray ionization mass spectrometry.

PubMed

Qian, Kuangnan; Edwards, Kathleen E; Dechert, Gary J; Jaffe, Stephen B; Green, Larry A; Olmstead, William N

2008-02-01

We report a new method for rapid measurement of total acid number (TAN) and TAN boiling point (BP) distribution for petroleum crude and products. The technology is based on negative ion electrospray ionization mass spectrometry (ESI-MS) for selective ionization of petroleum acid and quantification of acid structures and molecular weight distributions. A chip-based nanoelectrospray system enables microscale (<200 mg) and higher throughput (20 samples/h) measurement. Naphthenic acid structures were assigned based on nominal masses of a set of predefined acid structures. Stearic acid is used as an internal standard to calibrate ESI-MS response factors for quantification purposes. With the use of structure-property correlations, boiling point distributions of TAN values can be calculated from the composition. The rapid measurement of TAN BP distributions by ESI is demonstrated for a series of high-TAN crudes and distillation cuts. TAN values determined by the technique agree well with those by the titration method. The distributed properties compare favorably with those measured by distillation and measurement of TAN of corresponding cuts.

Semi-automatic segmentation of the placenta into fetal and maternal compartments using intravoxel incoherent motion MRI

NASA Astrophysics Data System (ADS)

You, Wonsang; Andescavage, Nickie; Zun, Zungho; Limperopoulos, Catherine

2017-03-01

Intravoxel incoherent motion (IVIM) magnetic resonance imaging is an emerging non-invasive technique that has been recently applied to quantify in vivo global placental perfusion. We propose a robust semi-automated method for segmenting the placenta into fetal and maternal compartments from IVIM data, using a multi-label image segmentation algorithm called `GrowCut'. Placental IVIM data were acquired on a 1.5T scanner from 16 healthy pregnant women between 21-37 gestational weeks. The voxel-wise perfusion fraction was then estimated after non-rigid image registration. The seed regions of the fetal and maternal compartments were determined using structural T2-weighted reference images, and improved progressively through an iterative process of the GrowCut algorithm to accurately encompass fetal and maternal compartments. We demonstrated that the placental perfusion fraction decreased in both fetal (-0.010/week) and maternal compartments (-0.013/week) while their relative difference (ffetal-fmaternal) gradually increased with advancing gestational age (+0.003/week, p=0.065). Our preliminary results show that the proposed method was effective in distinguishing placental compartments using IVIM.

Online machining error estimation method of numerical control gear grinding machine tool based on data analysis of internal sensors

NASA Astrophysics Data System (ADS)

Zhao, Fei; Zhang, Chi; Yang, Guilin; Chen, Chinyin

2016-12-01

This paper presents an online estimation method of cutting error by analyzing of internal sensor readings. The internal sensors of numerical control (NC) machine tool are selected to avoid installation problem. The estimation mathematic model of cutting error was proposed to compute the relative position of cutting point and tool center point (TCP) from internal sensor readings based on cutting theory of gear. In order to verify the effectiveness of the proposed model, it was simulated and experimented in gear generating grinding process. The cutting error of gear was estimated and the factors which induce cutting error were analyzed. The simulation and experiments verify that the proposed approach is an efficient way to estimate the cutting error of work-piece during machining process.

Obesity in Children: Definition, Etiology and Approach.

PubMed

Aggarwal, Bhawana; Jain, Vandana

2018-06-01

Childhood obesity is an important public health issue worldwide. Urbanization, sedentary lifestyle and change in food habits are the chief reasons behind this pandemic. In a small proportion of children, obesity is the result of endocrine, syndromic or monogenic causes. The present paper summarizes the methods, definitions and cut-offs for identification of obesity in children. We have briefly reviewed the various techniques used for estimation of body fat in children and the cut-offs for defining obesity based on body fat percentage, and the reference curves based on body mass index and waist circumference. The etiology of obesity in children, including individual behaviors, macro- and micro-environmental influences, and endocrine causes have been discussed, and an approach to etiological assessment of obese children has been presented. Special emphasis has been laid on clinical pointers that suggest the presence of syndromic, endocrine or monogenic forms of obesity, such as, short stature, dysmorphism, neurocognitive impairment and early age at onset.

Effects of harvesting cypress swamps on water quality and quantity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ewel, K.C.

1985-09-01

The responses of cypress swamps to a spectrum of harvest techniques are being studied in the Withlacoochee State Forest, Hernando County, Florida. Among the 11 swamps in the study area, four contain plots that were harvested experimentally in 1984. Stand improvement cuts were made in plots in two large swamps. Measurements of tree biomass were made in all but two of the large swamps. The swamps were surveyed for cone production in the fall and regeneration in the spring. However, coppice was produced in all the harvested plots. These preliminary results suggest that coppice production may be a dependable regenerationmore » method, although it may not be desirable for stand improvement cuts and thinning. Evapotranspiration from three cypress swamps averaged 79 cm over a 3-year period. The purpose of this project was to determine specific impacts of harvesting on water quality and water loss rates in the study areas.« less

[A graph cuts-based interactive method for segmentation of magnetic resonance images of meningioma].

PubMed

Li, Shuan-qiang; Feng, Qian-jin; Chen, Wu-fan; Lin, Ya-zhong

2011-06-01

For accurate segmentation of the magnetic resonance (MR) images of meningioma, we propose a novel interactive segmentation method based on graph cuts. The high dimensional image features was extracted, and for each pixel, the probabilities of its origin, either the tumor or the background regions, were estimated by exploiting the weighted K-nearest neighborhood classifier. Based on these probabilities, a new energy function was proposed. Finally, a graph cut optimal framework was used for the solution of the energy function. The proposed method was evaluated by application in the segmentation of MR images of meningioma, and the results showed that the method significantly improved the segmentation accuracy compared with the gray level information-based graph cut method.

26 CFR 1.669(c)-3A - Information requirements with respect to beneficiary.

Code of Federal Regulations, 2011 CFR

2011-04-01

... prior taxable year for which a recomputation is required under either the exact method or the short-cut... the tax computed under paragraph (c) of § 1.669(b)-1A (the short-cut method) shall be deemed to be the... exception to this rule where the short-cut method is not permitted. If he cannot furnish the information...

Study on boring hardened materials dryly by ultrasonic vibration cutter

NASA Astrophysics Data System (ADS)

Zhang, Jiangzhong; Zhang, Heng; Zhang, Yue

2011-05-01

It has been one of the difficulties that high-precision hole on hardened materials is machined. The supersonic vibration boring acoustic system in the lathe in which supersonic wave energy is applied on tool is introduced to create pulse power on the cutting process. The separation vibration cutting is achieved by the pulse force. The comparative tests on boring accuracy and surface quality are carried. The quality of surface machined by this method is compared to that by grinding. This cutting is the green cutting. The boring process system is stability. Under the condition that the cutting speed is less than or equal to 1/3 the tool vibration speed, the cutting force is pulse force and the Cutting energy is of high concentration in time, space and direction. The pulse energy effects on the cutting unit in less than one ten-thousandth second. Traditional cutting of irregular movement elastic compression are eliminated. The cutting force is greatly reduced. The cutting temperature is at room temperature. The tool life is greatly increased. Shape precision and surface quality is greatly improved. The regulations of the ultrasonic vibration boring dry cutting of hardened material are also summarized. The test results show that the ultrasonic vibration cutting tool boring is of very superior cutting mechanism and is a high-precision deep-hole machining of hardened materials, efficient cutting methods.

Machining process influence on the chip form and surface roughness by neuro-fuzzy technique

NASA Astrophysics Data System (ADS)

Anicic, Obrad; Jović, Srđan; Aksić, Danilo; Skulić, Aleksandar; Nedić, Bogdan

2017-04-01

The main aim of the study was to analyze the influence of six machining parameters on the chip shape formation and surface roughness as well during turning of Steel 30CrNiMo8. Three components of cutting forces were used as inputs together with cutting speed, feed rate, and depth of cut. It is crucial for the engineers to use optimal machining parameters to get the best results or to high control of the machining process. Therefore, there is need to find the machining parameters for the optimal procedure of the machining process. Adaptive neuro-fuzzy inference system (ANFIS) was used to estimate the inputs influence on the chip shape formation and surface roughness. According to the results, the cutting force in direction of the depth of cut has the highest influence on the chip form. The testing error for the cutting force in direction of the depth of cut has testing error 0.2562. This cutting force determines the depth of cut. According to the results, the depth of cut has the highest influence on the surface roughness. Also the depth of cut has the highest influence on the surface roughness. The testing error for the cutting force in direction of the depth of cut has testing error 5.2753. Generally the depth of cut and the cutting force which provides the depth of cut are the most dominant factors for chip forms and surface roughness. Any small changes in depth of cut or in cutting force which provide the depth of cut could drastically affect the chip form or surface roughness of the working material.

Research on subsurface deformed layer in ultra-precision cutting of single crystal copper by focused ion beam etching method

NASA Astrophysics Data System (ADS)

Chen, Y.; Huang, X. J.; Kong, J. X.

2018-03-01

In this paper, the focused ion beam was used to study the subsurface deformed layer of single crystal copper caused by the nanoscale single-point diamond fly cutting, and the possibility of using nanometer ultra-precision cutting to remove the larger deformation layer caused by traditional rough cutting process was explored. The maximum cutting thickness of single-point diamond cutting was about 146 nm, and the surface of the single-crystal copper after cutting was etched and observed by using the focused ion beam method. It was found that the morphology of the near-surface layer and the intermediate layer of the copper material were larger differences: the near-surface of the material was smaller and more compact, and the intermediate material layer of the material was more coarse sparse. The results showed that the traditional precision cutting would residual significant subsurface deformed layer and the thickness was on micron level. Even more, the subsurface deformed layer was obviously removed from about 12μm to 5μm after single-point diamond fly cutting in this paper. This paper proved that the large-scale subsurface deformed layer caused by traditional cutting process could be removed by nanometer ultra-precision cutting. It was of great significance to further establish the method that control of the deformation of weak rigid components by reducing the depth of the subsurface deformed layers.

Diameter-limit cutting in Appalachian hardwoods: boon or bane?

Treesearch

G.R., Jr. Trimble; G.R. Trimble

1971-01-01

Diameter-limit cutting is widespread and is applied in a great many ways, often without appreciation of its advantages and disadvantages and withoutan understanding of its effects on subsequent stand development. Although the technique has advantages, unless applied carefully, it can have longlasting adverse effects on sawtimber production. The latest results of...

Laser cutting eliminates nucleic acid cross-contamination in dried-blood-spot processing.

PubMed

Murphy, Sean C; Daza, Glenda; Chang, Ming; Coombs, Robert

2012-12-01

Dried blood spots (DBS) are useful for molecular assays but are prone to false positives from cross-contamination. In our malaria DBS assay, cross-contamination was encountered despite cleaning techniques suitable for HIV-1. We therefore developed a contact-free laser cutting system that effectively eliminated cross-contamination during DBS processing.

In vitro fenestration of aortic stent-grafts: implications of puncture methods for in situ fenestration durability.

PubMed

Riga, Celia V; Bicknell, Colin D; Basra, Melvinder; Hamady, Mohamad; Cheshire, Nicholas J W

2013-08-01

To investigate the quality of stent-graft fenestrations created in vitro using different needle puncture and balloon dilation angles in different commercial endografts. Fenestrations were made in a standardized fashion in 3 different endograft types: Talent monofilament twill woven polyester, Zenith multifilament tubular woven polyester, and Endofit thin-walled expanded polytetrafluoroethylene (PTFE). Punctures were made at 30°, 60°, and 90° angles using a 20-G needle and dilated using 6-mm standard and 7-mm cutting balloons; at least 6 fenestrations were made at each angle with standard balloons and at least 6 with cutting balloons. The 137 fenestrations were examined under light microscopy; quantitative and qualitative digital image analysis was performed to determine size, shape, and fenestration quality. PTFE grafts were easier to puncture/dilate, resulting in larger, elliptical fenestrations with overall better quality than the Dacron grafts; however, the puncture/dilation angle made an impact on the shape and quality of fenestrations. A significant number of fabric tears were observed in PTFE fabric at <90° puncture/dilation angles compared to Dacron grafts. In Dacron grafts, fenestration quality was significantly higher with 90° puncture/dilation angles (higher in Talent grafts). Cutting balloon use resulted in significantly more fabric tears and poor quality fenestrations in all graft types. Different endografts behave significantly differently when fenestrations are fashioned. Optimum puncture/dilation is important when considering in vivo fenestration techniques. Improvements in instrumentation, materials, and techniques are required to make this a reliable and reproducible endovascular option.

Observation of the pulp horn by swept source optical coherence tomography and cone beam computed tomography

NASA Astrophysics Data System (ADS)

Iino, Yoshiko; Yoshioka, Toshihiko; Hanada, Takahiro; Ebihara, Arata; Sunakawa, Mitsuhiro; Sumi, Yasunori; Suda, Hideaki

2015-02-01

Cone-beam computed tomography (CBCT) is one of the most useful diagnostic techniques in dentistry but it involves ionizing radiation, while swept source optical coherence tomography (SS-OCT) has been introduced recently as a nondestructive, real-time, high resolution imaging technique using low-coherence interferometry, which involves no ionizing radiation. The purpose of this study was to evaluate the ability of SS-OCT to detect the pulp horn (PH) in comparison with that of CBCT. Ten extracted human mandibular molars were used. After horizontally removing a half of the tooth crown, the distance from the cut dentin surface to PH was measured using microfocus computed tomography (Micro CT) (SL) as the gold standard, by CBCT (CL) and by SS-OCT (OL). In the SS-OCT images, only when PH was observed beneath the overlying dentin, the distance from the cut dentin surface to PH was recorded. If the pulp was exposed, it was defined as pulp exposure (PE). The results obtained by the above three methods were statistically analyzed by Spearman's rank correlation coefficient at a significance level of p < 0.01. SS-OCT detected the presence of PH when the distance from the cut dentin surface to PH determined by SL was 2.33 mm or less. Strong correlations of the measured values were found between SL and CL (r=0.87), SL and OL (r=0.96), and CL and OL (r=0.86). The results showed that SS-OCT images correlated closely with CBCT images, suggesting that SS-OCT can be a useful tool for the detection of PH.

Finite element simulation of cutting grey iron HT250 by self-prepared Si3N4 ceramic insert

NASA Astrophysics Data System (ADS)

Wang, Bo; Wang, Li; Zhang, Enguang

2017-04-01

The finite element method has been able to simulate and solve practical machining problems, achieve the required accuracy and the highly reliability. In this paper, the simulation models based on the material properties of the self-prepared Si3N4 insert and HT250 were created. Using these models, the results of cutting force, cutting temperature and tool wear rate were obtained, and tool wear mode was predicted after cutting simulation. These approaches may develop as the new method for testing new cutting-tool materials, shortening development cycle and reducing the cost.

Key improvements in machining of Ti6al4v alloy: A review

NASA Astrophysics Data System (ADS)

Katta, Sivakoteswararao; Chaitanya, G.

2017-07-01

Now a days the use of ti-6al-4v alloy is high in demand in many industries like aero space, bio medical automobile, space, military etc. the production rates in the industries are not sufficient because the machiniability of ti-6al-4v is the main problem, there are several cutting tools available for metal cutting operations still there is a gap in finding the proper cutting tool material for machining of ti-6al-4v. because the properties of titanium like high heat resistant, low thermal conductivity, low weight ratio, less corrosiveness, and more many properties attracting the industrialists to use titanium as their material for their products, many researchers done the research on machininbility of ti-6al-4v by using different tool materials. but as for my literature survey there is still lot of scope is available, to find better cutting tool with techniques for machining ti-6al-4v. in this paper iam discussing the work done by various researchers on ti-6al-4v alloy with different techniques.

RESEARCH: Shrub Propagation Techniques for Biological Control ofInvading Tree Species

PubMed

Meilleur; Veronneau; Bouchard

1997-05-01

/ The use of relatively stable shrub communities to control invasionby trees could be an efficient way of reducing herbicide applications, andthus represents an environmental gain, in areas such as rights-of-way. Thequestion is how to favor the expansion of these relatively stable shrubcommunities using different propagation techniques. Three experimentaltreatments, cutting back, layering, and cutting back-layering were performedon Cornus stolonifera, Salix petiolaris, and Spiraea albaclones already located within the corridor of an electrical power line. Toestablish the efficiency of treatments, we examined the statisticaldifferences of growth traits between species and treatments.An analysis of the effects of layering shows, after the first growth season,differences for all growth traits in only one species, Spiraea alba.After the second growth season, we observed the development of new aerialstems. Layering favors horizontal expansion of shrubs over heightdevelopment. The third year after treatment, the effect of layering isreduced except for Cornus stolonifera, which continuously increases,as shown by the significant progression of the clone issued from the layereven five years after treatments. With the cutting back technique, weexpected a distinct vertical growth of the shrubs at the expense ofincreasing the crown diameter. This technique would be best associated withthe rejuvenation of clones, followed by a layering of new shoots to allow ahorizontal expansion of the shrubs. Therefore, the formation of a dense shrubcommunity by layering should be considered a valuable approach for thebiological control of undesirable trees in powerline rights-of-way.KEY WORDS: Layering; Cutting back; Right-of-way; Cornus stolonifera;Salix petiolaris; Spiraea alba; Quebec

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.

Online breakage detection of multitooth tools using classifier ensembles for imbalanced data

NASA Astrophysics Data System (ADS)

Bustillo, Andrés; Rodríguez, Juan J.

2014-12-01

Cutting tool breakage detection is an important task, due to its economic impact on mass production lines in the automobile industry. This task presents a central limitation: real data-sets are extremely imbalanced because breakage occurs in very few cases compared with normal operation of the cutting process. In this paper, we present an analysis of different data-mining techniques applied to the detection of insert breakage in multitooth tools. The analysis applies only one experimental variable: the electrical power consumption of the tool drive. This restriction profiles real industrial conditions more accurately than other physical variables, such as acoustic or vibration signals, which are not so easily measured. Many efforts have been made to design a method that is able to identify breakages with a high degree of reliability within a short period of time. The solution is based on classifier ensembles for imbalanced data-sets. Classifier ensembles are combinations of classifiers, which in many situations are more accurate than individual classifiers. Six different base classifiers are tested: Decision Trees, Rules, Naïve Bayes, Nearest Neighbour, Multilayer Perceptrons and Logistic Regression. Three different balancing strategies are tested with each of the classifier ensembles and compared to their performance with the original data-set: Synthetic Minority Over-Sampling Technique (SMOTE), undersampling and a combination of SMOTE and undersampling. To identify the most suitable data-mining solution, Receiver Operating Characteristics (ROC) graph and Recall-precision graph are generated and discussed. The performance of logistic regression ensembles on the balanced data-set using the combination of SMOTE and undersampling turned out to be the most suitable technique. Finally a comparison using industrial performance measures is presented, which concludes that this technique is also more suited to this industrial problem than the other techniques presented in the bibliography.

Combustion of bulk titanium in oxygen

NASA Technical Reports Server (NTRS)

Clark, A. F.; Moulder, J. C.; Runyan, C. C.

1975-01-01

The combustion of bulk titanium in one atmosphere oxygen is studied using laser ignition and several analytical techniques. These were high-speed color cinematography, time and space resolved spectra in the visible region, metallography (including SEM) of specimens quenched in argon gas, X-ray and chemical product analyses, and a new optical technique, the Hilbert transform method. The cinematographic application of this technique for visualizing phase objects in the combustion zone is described. The results indicate an initial vapor phase reaction immediately adjacent to the molten surface but as the oxygen uptake progresses the evaporation approaches the point of congruency and a much reduced evaporation rate. This and the accumulation of the various soluble oxides soon drive the reaction zone below the surface where gas formation causes boiling and ejection of particles. The buildup of rutile cuts off the oxygen supply and the reaction ceases.

Generation of segmental chips in metal cutting modeled with the PFEM

NASA Astrophysics Data System (ADS)

Rodriguez Prieto, J. M.; Carbonell, J. M.; Cante, J. C.; Oliver, J.; Jonsén, P.

2018-06-01

The Particle Finite Element Method, a lagrangian finite element method based on a continuous Delaunay re-triangulation of the domain, is used to study machining of Ti6Al4V. In this work the method is revised and applied to study the influence of the cutting speed on the cutting force and the chip formation process. A parametric methodology for the detection and treatment of the rigid tool contact is presented. The adaptive insertion and removal of particles are developed and employed in order to sidestep the difficulties associated with mesh distortion, shear localization as well as for resolving the fine-scale features of the solution. The performance of PFEM is studied with a set of different two-dimensional orthogonal cutting tests. It is shown that, despite its Lagrangian nature, the proposed combined finite element-particle method is well suited for large deformation metal cutting problems with continuous chip and serrated chip formation.

Generation of segmental chips in metal cutting modeled with the PFEM

NASA Astrophysics Data System (ADS)

Rodriguez Prieto, J. M.; Carbonell, J. M.; Cante, J. C.; Oliver, J.; Jonsén, P.

2017-09-01

The Particle Finite Element Method, a lagrangian finite element method based on a continuous Delaunay re-triangulation of the domain, is used to study machining of Ti6Al4V. In this work the method is revised and applied to study the influence of the cutting speed on the cutting force and the chip formation process. A parametric methodology for the detection and treatment of the rigid tool contact is presented. The adaptive insertion and removal of particles are developed and employed in order to sidestep the difficulties associated with mesh distortion, shear localization as well as for resolving the fine-scale features of the solution. The performance of PFEM is studied with a set of different two-dimensional orthogonal cutting tests. It is shown that, despite its Lagrangian nature, the proposed combined finite element-particle method is well suited for large deformation metal cutting problems with continuous chip and serrated chip formation.

Method of modifying a volume mesh using sheet insertion

DOEpatents

Borden, Michael J [Albuquerque, NM; Shepherd, Jason F [Albuquerque, NM

2006-08-29

A method and machine-readable medium provide a technique to modify a hexahedral finite element volume mesh using dual generation and sheet insertion. After generating a dual of a volume stack (mesh), a predetermined algorithm may be followed to modify (refine) the volume mesh of hexahedral elements. The predetermined algorithm may include the steps of locating a sheet of hexahedral mesh elements, determining a plurality of hexahedral elements within the sheet to refine, shrinking the plurality of elements, and inserting a new sheet of hexahedral elements adjacently to modify the volume mesh. Additionally, another predetermined algorithm using mesh cutting may be followed to modify a volume mesh.

Cutting and coagulation during intraoral soft tissue surgery using Er: YAG laser.

PubMed

Onisor, I; Pecie, R; Chaskelis, I; Krejci, I

2013-06-01

To find the optimal techniques and parameters that enables Er:YAG laser to be used successfully for small intraoral soft tissue interventions, in respect to its cutting and coagulation abilities. In vitro pre-tests: 4 different Er:YAG laser units and one CO2 unit as the control were used for incision and coagulation on porcine lower jaws and optimal parameters were established for each type of intervention and each laser unit: energy, frequency, type, pulse duration and distance. 3 different types of intervention using Er:YAG units are presented: crown lengthening, gingivoplasty and maxillary labial frenectomy with parameters found in the in vitro pre-tests. The results showed a great decrease of the EMG activity of masseter and anterior temporalis muscles. Moreover, the height and width of the chewing cycles in the frontal plane increased after therapy. Er:YAG is able to provide good cutting and coagulation effects on soft tissues. Specific parameters have to be defined for each laser unit in order to obtain the desired effect. Reduced or absent water spray, defocused light beam, local anaesthesia and the most effective use of long pulses are methods to obtain optimal coagulation and bleeding control.

CPU-GPU mixed implementation of virtual node method for real-time interactive cutting of deformable objects using OpenCL.

PubMed

Jia, Shiyu; Zhang, Weizhong; Yu, Xiaokang; Pan, Zhenkuan

2015-09-01

Surgical simulators need to simulate interactive cutting of deformable objects in real time. The goal of this work was to design an interactive cutting algorithm that eliminates traditional cutting state classification and can work simultaneously with real-time GPU-accelerated deformation without affecting its numerical stability. A modified virtual node method for cutting is proposed. Deformable object is modeled as a real tetrahedral mesh embedded in a virtual tetrahedral mesh, and the former is used for graphics rendering and collision, while the latter is used for deformation. Cutting algorithm first subdivides real tetrahedrons to eliminate all face and edge intersections, then splits faces, edges and vertices along cutting tool trajectory to form cut surfaces. Next virtual tetrahedrons containing more than one connected real tetrahedral fragments are duplicated, and connectivity between virtual tetrahedrons is updated. Finally, embedding relationship between real and virtual tetrahedral meshes is updated. Co-rotational linear finite element method is used for deformation. Cutting and collision are processed by CPU, while deformation is carried out by GPU using OpenCL. Efficiency of GPU-accelerated deformation algorithm was tested using block models with varying numbers of tetrahedrons. Effectiveness of our cutting algorithm under multiple cuts and self-intersecting cuts was tested using a block model and a cylinder model. Cutting of a more complex liver model was performed, and detailed performance characteristics of cutting, deformation and collision were measured and analyzed. Our cutting algorithm can produce continuous cut surfaces when traditional minimal element creation algorithm fails. Our GPU-accelerated deformation algorithm remains stable with constant time step under multiple arbitrary cuts and works on both NVIDIA and AMD GPUs. GPU-CPU speed ratio can be as high as 10 for models with 80,000 tetrahedrons. Forty to sixty percent real-time performance and 100-200 Hz simulation rate are achieved for the liver model with 3,101 tetrahedrons. Major bottlenecks for simulation efficiency are cutting, collision processing and CPU-GPU data transfer. Future work needs to improve on these areas.

Shot boundary detection and label propagation for spatio-temporal video segmentation

NASA Astrophysics Data System (ADS)

Piramanayagam, Sankaranaryanan; Saber, Eli; Cahill, Nathan D.; Messinger, David

2015-02-01

This paper proposes a two stage algorithm for streaming video segmentation. In the first stage, shot boundaries are detected within a window of frames by comparing dissimilarity between 2-D segmentations of each frame. In the second stage, the 2-D segments are propagated across the window of frames in both spatial and temporal direction. The window is moved across the video to find all shot transitions and obtain spatio-temporal segments simultaneously. As opposed to techniques that operate on entire video, the proposed approach consumes significantly less memory and enables segmentation of lengthy videos. We tested our segmentation based shot detection method on the TRECVID 2007 video dataset and compared it with block-based technique. Cut detection results on the TRECVID 2007 dataset indicate that our algorithm has comparable results to the best of the block-based methods. The streaming video segmentation routine also achieves promising results on a challenging video segmentation benchmark database.

Laminated and infused Parafilm® - paper for paper-based analytical devices.

PubMed

Kim, Yong Shin; Yang, Yuanyuan; Henry, Charles S

2018-02-01

Numerous fabrication methods have been reported for microfluidic paper-based analytical devices (μPADs) using barrier materials ranging from photoresist to wax. While these methods have been used with wide success, consistently producing small, high-resolution features using materials and methods that are compatible with solvents and surfactants remains a challenge. Two new methods are presented here for generating μPADs with well-defined, high-resolution structures compatible with solvents and surfactant-containing solutions by partially or fully fusing paper with Parafilm® followed by cutting with a CO 2 laser cutter. Partial fusion leads to laminated paper ( l -paper) while the complete fusion results in infused paper ( i -paper). Patterned structures in l -paper were fabricated by selective removal of the paper but not the underlying Parafilm® using a benchtop CO 2 laser. Under optimized conditions, a gap as small as 137 ± 22 μm could be generated. Using this approach, a miniaturized paper 384-zone plate, consisting of circular detection elements with a diameter of 1.86 mm, was fabricated in 64 × 43 mm 2 area. Furthermore, these ablation-patterned substrates were confirmed to be compatible with surfactant solutions and common organic solvents (methanol, acetonitrile and dimethylformamide), which has been achieved by very few μPAD patterning techniques. Patterns in i -paper were created by completely cutting out zones of the i -paper and then fixing pre-cut paper into these openings similar to the strategy of fitting a jigsaw piece into a puzzle. Upon heating, unmodified paper was readily sealed into these openings due to partial reflow of the paraffin into the paper. This unique and simple bonding method was illustrated by two types of 3D μPADs, a push-on valve and a time-gated flow distributor, without adding adhesive layers. The free-standing jigsaw-patterned sheets showed good structural stability and solution compatibility, which provided a facile alternative method for fabricating complicated μPADs.

Technique for predicting ground-water discharge to surface coal mines and resulting changes in head

USGS Publications Warehouse

Weiss, L.S.; Galloway, D.L.; Ishii, Audrey L.

1986-01-01

Changes in seepage flux and head (groundwater level) from groundwater drainage into a surface coal mine can be predicted by a technique that considers drainage from the unsaturated zone. The user applies site-specific data to precalculated head and seepage-flux profiles. Groundwater flow through hypothetical aquifer cross sections was simulated using the U.S. Geological Survey finite-difference model, VS2D, which considers variably saturated two-dimensional flow. Conceptual models considered were (1) drainage to a first cut, and (2) drainage to multiple cuts, which includes drainage effects of an area surface mine. Dimensionless head and seepage flux profiles from 246 simulations are presented. Step-by-step instructions and examples are presented. Users are required to know aquifer characteristics and to estimate size and timing of the mine operation at a proposed site. Calculated groundwater drainage to the mine is from one excavated face only. First cut considers confined and unconfined aquifers of a wide range of permeabilities; multiple cuts considers unconfined aquifers of higher permeabilities only. The technique, developed for Illinois coal-mining regions that use area surface mining and evaluated with an actual field example, will be useful in assessing potential hydrologic impacts of mining. Application is limited to hydrogeologic settings and mine operations similar to those considered. Fracture flow, recharge, and leakage are nor considered. (USGS)

Comparison of nerve trimming with the Er:YAG laser and steel knife

NASA Astrophysics Data System (ADS)

Josephson, G. D.; Bass, Lawrence S.; Kasabian, A. K.

1995-05-01

Best outcome in nerve repair requires precise alignment and minimization of scar at the repair interface. Surgeons attempt to create the sharpest cut surface at the nerve edge prior to approximation. Pulsed laser modalities are being investigated in several medical applications which require precise atraumatic cutting. We compared nerve trimming with the Er:YAG laser (1375 J/cm2) to conventional steel knife trimming prior to neurorrhaphy. Sprague- Dawley rats were anesthetized with ketamine and xylazine. Under operating microscope magnification the sciatic nerve was dissected and transected using one of the test techniques. In the laser group, the pulses were directed axially across the nerve using a stage which fixed laser fiber/nerve distance and orientation. Specimens were sent for scanning electron microscopy (SEM) at time zero. Epineurial repairs were performed with 10 - 0 nylon simple interrupted sutures. At intervals to 90 days, specimens were harvested and sectioned longitudinally and axially for histologic examination. Time zero SEM revealed clean cuts in both groups but individual axons were clearly visible in all laser specimens. Small pits were also visible on the cut surface of laser treated nerves. No significant differences in nerve morphology were seen during healing. Further studies to quantify axon counts, and functional outcome will be needed to assess this technique of nerve trimming. Delivery system improvements will also be required, to make the technique clinically practical.

Analysis and Validation of Contactless Time-Gated Interrogation Technique for Quartz Resonator Sensors

PubMed Central

Baù, Marco; Ferrari, Marco; Ferrari, Vittorio

2017-01-01

A technique for contactless electromagnetic interrogation of AT-cut quartz piezoelectric resonator sensors is proposed based on a primary coil electromagnetically air-coupled to a secondary coil connected to the electrodes of the resonator. The interrogation technique periodically switches between interleaved excitation and detection phases. During the excitation phase, the resonator is set into vibration by a driving voltage applied to the primary coil, whereas in the detection phase, the excitation signal is turned off and the transient decaying response of the resonator is sensed without contact by measuring the voltage induced back across the primary coil. This approach ensures that the readout frequency of the sensor signal is to a first order approximation independent of the interrogation distance between the primary and secondary coils. A detailed theoretical analysis of the interrogation principle based on a lumped-element equivalent circuit is presented. The analysis has been experimentally validated on a 4.432 MHz AT-cut quartz crystal resonator, demonstrating the accurate readout of the series resonant frequency and quality factor over an interrogation distance of up to 2 cm. As an application, the technique has been applied to the measurement of liquid microdroplets deposited on a 4.8 MHz AT-cut quartz crystal. More generally, the proposed technique can be exploited for the measurement of any physical or chemical quantities affecting the resonant response of quartz resonator sensors. PMID:28574459

Analysis and Validation of Contactless Time-Gated Interrogation Technique for Quartz Resonator Sensors.

PubMed

Baù, Marco; Ferrari, Marco; Ferrari, Vittorio

2017-06-02

A technique for contactless electromagnetic interrogation of AT-cut quartz piezoelectric resonator sensors is proposed based on a primary coil electromagnetically air-coupled to a secondary coil connected to the electrodes of the resonator. The interrogation technique periodically switches between interleaved excitation and detection phases. During the excitation phase, the resonator is set into vibration by a driving voltage applied to the primary coil, whereas in the detection phase, the excitation signal is turned off and the transient decaying response of the resonator is sensed without contact by measuring the voltage induced back across the primary coil. This approach ensures that the readout frequency of the sensor signal is to a first order approximation independent of the interrogation distance between the primary and secondary coils. A detailed theoretical analysis of the interrogation principle based on a lumped-element equivalent circuit is presented. The analysis has been experimentally validated on a 4.432 MHz AT-cut quartz crystal resonator, demonstrating the accurate readout of the series resonant frequency and quality factor over an interrogation distance of up to 2 cm. As an application, the technique has been applied to the measurement of liquid microdroplets deposited on a 4.8 MHz AT-cut quartz crystal. More generally, the proposed technique can be exploited for the measurement of any physical or chemical quantities affecting the resonant response of quartz resonator sensors.

ESDA®-Lite collection of DNA from latent fingerprints on documents.

PubMed

Plaza, Dane T; Mealy, Jamia L; Lane, J Nicholas; Parsons, M Neal; Bathrick, Abigail S; Slack, Donia P

2015-05-01

The ability to detect and non-destructively collect biological samples for DNA processing would benefit the forensic community by preserving the physical integrity of evidentiary items for more thorough evaluations by other forensic disciplines. The Electrostatic Detection Apparatus (ESDA®) was systemically evaluated for its ability to non-destructively collect DNA from latent fingerprints deposited on various paper substrates for short tandem repeat (STR) DNA profiling. Fingerprints were deposited on a variety of paper substrates that included resume paper, cotton paper, magazine paper, currency, copy paper, and newspaper. Three DNA collection techniques were performed: ESDA collection, dry swabbing, and substrate cutting. Efficacy of each collection technique was evaluated by the quantity of DNA present in each sample and the percent profile generated by each sample. Both the ESDA and dry swabbing non-destructive sampling techniques outperformed the destructive methodology of substrate cutting. A greater number of full profiles were generated from samples collected with the non-destructive dry swabbing collection technique than were generated from samples collected with the ESDA; however, the ESDA also allowed the user to visualize the area of interest while non-destructively collecting the biological material. The ability to visualize the biological material made sampling straightforward and eliminated the need for numerous, random swabbings/cuttings. Based on these results, the evaluated non-destructive ESDA collection technique has great potential for real-world forensic implementation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Mitigating cutting-induced plasticity in the contour method, Part 2: Numerical analysis

DOE PAGES

Muránsky, O.; Hamelin, C. J.; Hosseinzadeh, F.; ...

2016-02-10

Cutting-induced plasticity can have a significant effect on the measurement accuracy of the contour method. The present study examines the benefit of a double-embedded cutting configuration that relies on self-restraint of the specimen, relative to conventional edge-crack cutting configurations. A series of finite element analyses are used to simulate the planar sectioning performed during double-embedded and conventional edge-crack contour cutting configurations. The results of numerical analyses are first compared to measured results to validate the cutting simulations. The simulations are then used to compare the efficacy of different cutting configurations by predicting the deviation of the residual stress profile frommore » an original (pre-cutting) reference stress field, and the extent of cutting-induced plasticity. Comparisons reveal that while the double-embedded cutting configuration produces the most accurate residual stress measurements, the highest levels of plastic flow are generated in this process. As a result, this cutting-induced plastic deformation is, however, largely confined to small ligaments formed as a consequence of the sample sectioning process, and as such it does not significantly affect the back-calculated residual stress field.« less

Mitigating cutting-induced plasticity in the contour method, Part 2: Numerical analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muránsky, O.; Hamelin, C. J.; Hosseinzadeh, F.

Cutting-induced plasticity can have a significant effect on the measurement accuracy of the contour method. The present study examines the benefit of a double-embedded cutting configuration that relies on self-restraint of the specimen, relative to conventional edge-crack cutting configurations. A series of finite element analyses are used to simulate the planar sectioning performed during double-embedded and conventional edge-crack contour cutting configurations. The results of numerical analyses are first compared to measured results to validate the cutting simulations. The simulations are then used to compare the efficacy of different cutting configurations by predicting the deviation of the residual stress profile frommore » an original (pre-cutting) reference stress field, and the extent of cutting-induced plasticity. Comparisons reveal that while the double-embedded cutting configuration produces the most accurate residual stress measurements, the highest levels of plastic flow are generated in this process. As a result, this cutting-induced plastic deformation is, however, largely confined to small ligaments formed as a consequence of the sample sectioning process, and as such it does not significantly affect the back-calculated residual stress field.« less

The Control of Invasive Knotweed Species (Fallopia sp.). Research Experiences from Austria

NASA Astrophysics Data System (ADS)

Lammeranner, Walter; Schmidt, Christina; Eitler, Manuela; Natascha, Steinbauer

2013-04-01

The alien plant species Fallopia japonica (Japanese Knotweed), Fallopia sachalinensis (Sakhalin Knotweed) and the clonal knotweed hybrid Fallopia × bohemica are invasive plant species which spread out within Europe. They often form dense stands along Rivers and have negative impacts on biodiversity and ecosystem functioning and also threaten the stability of river banks. Due to their life form, vitality and their enormous ability to regenerate themselves, they are extremely hard to fight. The control measurements against Fallopia species are therefore complicated and often do not have the desired results. Our research tried two approaches to deal with these invasive plant species. The first approach was the use of soil bioengineering techniques which have considerable potential for the management of Fallopia. In our study at the river Schwechat (Lower Austria) we tested two soil bioengineering methods for the control of Fallopia. The first method was the use of living brush mattresses with willows (Salix sp.) to fight the growth of Fallopia species. Within a second method a black liner was used in combination with willow cuttings. After cutting the Fallopia stands the liner was applied to the river bank and fixed with living willow cutting to the surface. The two areas were compared to untreated river bank areas. At several points of time we compared the aboveground response (number of shoots, basal shoot diameters, plant heights, number of stems, aboveground biomass). Additionally the aboveground plant parameters of the willows were measured. In a second approach it was tested if Fallopia can be suppressed or even exterminated if they are submerged for longer time periods. For the experiments Fallopia rhizomes were planted in plastic containers. After a certain growing period, the plants were cut and documented quantitatively by the measurements of shoot lengths, shoot diameters and aboveground biomass. After the first harvest the containers were flooded with water over a period of 1 to 9 weeks. After flooding the regrowth of Fallopia was observed. Our contribution describes the methods used and shows the results of the studies.

Multivariate meta-analysis of prognostic factor studies with multiple cut-points and/or methods of measurement.

PubMed

Riley, Richard D; Elia, Eleni G; Malin, Gemma; Hemming, Karla; Price, Malcolm P

2015-07-30

A prognostic factor is any measure that is associated with the risk of future health outcomes in those with existing disease. Often, the prognostic ability of a factor is evaluated in multiple studies. However, meta-analysis is difficult because primary studies often use different methods of measurement and/or different cut-points to dichotomise continuous factors into 'high' and 'low' groups; selective reporting is also common. We illustrate how multivariate random effects meta-analysis models can accommodate multiple prognostic effect estimates from the same study, relating to multiple cut-points and/or methods of measurement. The models account for within-study and between-study correlations, which utilises more information and reduces the impact of unreported cut-points and/or measurement methods in some studies. The applicability of the approach is improved with individual participant data and by assuming a functional relationship between prognostic effect and cut-point to reduce the number of unknown parameters. The models provide important inferential results for each cut-point and method of measurement, including the summary prognostic effect, the between-study variance and a 95% prediction interval for the prognostic effect in new populations. Two applications are presented. The first reveals that, in a multivariate meta-analysis using published results, the Apgar score is prognostic of neonatal mortality but effect sizes are smaller at most cut-points than previously thought. In the second, a multivariate meta-analysis of two methods of measurement provides weak evidence that microvessel density is prognostic of mortality in lung cancer, even when individual participant data are available so that a continuous prognostic trend is examined (rather than cut-points). © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Validation of the FFM PD count technique for screening personality pathology in later middle-aged and older adults.

PubMed

Van den Broeck, Joke; Rossi, Gina; De Clercq, Barbara; Dierckx, Eva; Bastiaansen, Leen

2013-01-01

Research on the applicability of the five factor model (FFM) to capture personality pathology coincided with the development of a FFM personality disorder (PD) count technique, which has been validated in adolescent, young, and middle-aged samples. This study extends the literature by validating this technique in an older sample. Five alternative FFM PD counts based upon the Revised NEO Personality Inventory (NEO PI-R) are computed and evaluated in terms of both convergent and divergent validity with the Assessment of DSM-IV Personality Disorders Questionnaire (shortly ADP-IV; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders - Fourth edition). For the best working count for each PD normative data are presented, from which cut-off scores are derived. The validity of these cut-offs and their usefulness as a screening tool is tested against both a categorical (i.e., the DSM-IV - Text Revision), and a dimensional (i.e., the Dimensional Assessment of Personality Pathology; DAPP) measure of personality pathology. All but the Antisocial and Obsessive-Compulsive counts exhibited adequate convergent and divergent validity, supporting the use of this method in older adults. Using the ADP-IV and the DAPP - Short Form as validation criteria, results corroborate the use of the FFM PD count technique to screen for PDs in older adults, in particular for the Paranoid, Borderline, Histrionic, Avoidant, and Dependent PDs. Given the age-neutrality of the NEO PI-R and the considerable lack of valid personality assessment tools, current findings appear to be promising for the assessment of pathology in older adults.

The Big-Bubble Full Femtosecond Laser-Assisted Technique in Deep Anterior Lamellar Keratoplasty.

PubMed

Buzzonetti, Luca; Petrocelli, Gianni; Valente, Paola; Iarossi, Giancarlo; Ardia, Roberta; Petroni, Sergio; Parrilla, Rosa

2015-12-01

To describe the big-bubble full femtosecond laser-assisted (BBFF) technique, which could be helpful in standardizing the big-bubble technique in deep anterior lamellar keratoplasty (DALK). Ten eyes of 10 consecutive patients affected by keratoconus underwent the BBFF technique using the 150-kHz IntraLase femtosecond laser (Intra-Lase FS Laser; Abbott Medical Optics, Inc., Santa Ana, CA). A 9-mm diameter metal mask with a single fissure 0.7 mm wide oriented at the 12-o'clock position was positioned into the cone, over the laser glass. The laser performed a ring lamellar cut (internal diameter = 3 mm; external diameter = 8 mm) 100 µm above the thinnest point, with the photodisruption effectively occurring only in the corneal stroma corresponding to the fissure to create a deep stromal channel; subsequently, an anterior side cut created an arcuate incision, from the corneal surface to the deep stromal channel on the mask's opening site. The mask was removed and the laser performed a full lamellar cut 200 µm above the thinnest point to create a lamella. After the removal of the lamella, the air needle was inserted into the stromal channel and air was injected to achieve a big bubble. The big bubble was achieved in 9 eyes (all type 1 bubbles) and all procedures were completed as DALK. Preliminary results suggest that the BBFF technique could help in standardizing the big-bubble technique in DALK, reducing the "learning curve" for surgeons who approach this technique and the risks of intraoperative complications. Copyright 2015, SLACK Incorporated.

3D assembly of carbon nanotubes for fabrication of field-effect transistors through nanomanipulation and electron-beam-induced deposition

NASA Astrophysics Data System (ADS)

Yu, Ning; Shi, Qing; Nakajima, Masahiro; Wang, Huaping; Yang, Zhan; Sun, Lining; Huang, Qiang; Fukuda, Toshio

2017-10-01

Three-dimensional carbon nanotube field-effect transistors (3D CNTFETs) possess predictable characteristics that rival those of planar CNTFETs and Si-based MOSFETs. However, due to the lack of a reliable assembly technology, they are rarely reported on, despite the amount of attention they receive. To address this problem, we propose the novel concept of a 3D CNTFET and develop its assembly strategy based on nanomanipulation and the electron-beam-induced deposition (EBID) technique inside a scanning electron microscope (SEM). In particular, the electrodes in our transistor design are three metallic cuboids of the same size, and their front, top and back surfaces are all wrapped up in CNTs. The assembly strategy is employed to build the structure through a repeated basic process of pick-up, placement, fixing and cutting of CNTs. The pick-up and placement is performed through one nanomanipulator with four degrees of freedom. Fixing is carried out through the EBID technique so as to improve the mechanical and electrical characteristics of the CNT/electrodes connection. CNT cutting is undertaken using the typical method of electrical breakdown. Experimental results showed that two CNTs were successfully assembled on the front sides of the cubic electrodes. This validates our assembly method for the 3D CNTFET. Also, when contact resistance was measured, tens of kilohms of resistance was observed at the CNT-EBID deposition-FET electrodes junction.. This manifests the electrical reliability of our assembly strategy.

Vegetative propagation of Cecropia obtusifolia (Cecropiaceae).

PubMed

LaPierre, L M

2001-01-01

Cecropia is a relatively well-known and well-studied genus in the Neotropics. Methods for the successful propagation of C. obtusifolia Bertoloni, 1840 from cuttings and air layering are described, and the results of an experiment to test the effect of two auxins, naphthalene acetic acid (NAA) and indole butyric acid (IBA), on adventitious root production in cuttings are presented. In general, C. obtusifolia cuttings respond well to adventitious root production (58.3% of cuttings survived to root), but air layering was the better method (93% of cuttings survived to root). The concentration of auxins used resulted in an overall significantly lower quality of roots produced compared with cuttings without auxin treatment. Future experiments using Cecropia could benefit from the use of isogenic plants produced by vegetative propagation.

Method and apparatus for diamond wire cutting of metal structures

DOEpatents

Parsells, Robert; Gettelfinger, Geoff; Perry, Erik; Rule, Keith

2005-04-19

A method and apparatus for diamond wire cutting of metal structures, such as nuclear reactor vessels, is provided. A diamond wire saw having a plurality of diamond beads with beveled or chamfered edges is provided for sawing into the walls of the metal structure. The diamond wire is guided by a plurality of support structures allowing for a multitude of different cuts. The diamond wire is cleaned and cooled by CO.sub.2 during the cutting process to prevent breakage of the wire and provide efficient cutting. Concrete can be provided within the metal structure to enhance cutting efficiency and reduce airborne contaminants. The invention can be remotely controlled to reduce exposure of workers to radioactivity and other hazards.

Volume reduction of hot cell plastic wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dykes, F W; Henscheid, J P; Lewis, L C

1989-09-19

The disposal of radioactively-contaminated solid wastes has become a national crisis. In such circumstances, it is imperative that this waste be reduced to minimum volume and be packaged to prevent pollution of the environment. The majority of the solid waste generated at the hot cell under consideration is plastic lab ware. Cutting this waste into small pieces with a hot wire technique reduced the volume 66%. Melting the waste, although more time consuming, reduced the volume 90%. The hot wire technique can also be used to cut up damaged master slave manipulator boots, greatly reducing their disposal volume.

Use of Piezosurgery for removal of retrovertebral body osteophytes in anterior cervical discectomy.

PubMed

Grauvogel, Juergen; Scheiwe, Christian; Kaminsky, Jan

2014-04-01

The relatively new technique of Piezosurgery is based on microvibrations, generated by the piezoelectrical effect, which results in selective bone cutting with preservation of adjacent soft tissue. To study the applicability of Piezosurgery in anterior cervical discectomy with fusion (ACDF) surgery. Prospective clinical study at the neurosurgical department of the University of Freiburg, Germany. Nine patients with cervical disc herniation and retrovertebral osteophytes who underwent ACDF surgery. Piezosurgery was evaluated with respect to practicability, safety, preciseness of bone cutting, and preservation of adjacent neurovascular tissue. Pre- and postoperative clinical and radiological data were assessed. Piezosurgery was supportively used in ACDF in nine patients with either radiculopathy or myelopathy from disc herniation or ventral osteophytes. After discectomy, osteophytes were removed with Piezosurgery to decompress the spinal canal and the foramina. Angled inserts were used, allowing for cutting even retrovertebral osteophytes. In all nine cases, Piezosurgery cut bone selectively with no damage to nerve roots, dura, or posterior longitudinal ligament. None of the patients experienced any new neurological deficit after the operation. The handling of the instrument was safe and the cut precise. Osteophytic spurs, even retrovertebral ones that generally only can be approached via corpectomies, could be safely removed because of the angled inserts through the disc space. Currently, a slightly prolonged operation time was observed for Piezosurgery. Furthermore, the design of the handpiece could be further improved to facilitate the intraoperative handling in ACDF. Piezosurgery proved to be a useful and safe technique for selective bone cutting and removal of osteophytes with preservation of neuronal and soft tissue in ACDF. In particular, the angled inserts were effective in cutting bone spurs behind the adjacent vertebra which cannot be reached with conventional rotating burs. Copyright © 2014 Elsevier Inc. All rights reserved.

The Objective Borderline Method (OBM): A Probability-Based Model for Setting up an Objective Pass/Fail Cut-Off Score in Medical Programme Assessments

ERIC Educational Resources Information Center

Shulruf, Boaz; Turner, Rolf; Poole, Phillippa; Wilkinson, Tim

2013-01-01

The decision to pass or fail a medical student is a "high stakes" one. The aim of this study is to introduce and demonstrate the feasibility and practicality of a new objective standard-setting method for determining the pass/fail cut-off score from borderline grades. Three methods for setting up pass/fail cut-off scores were compared: the…

Comparison of silvicultural and natural disturbance effects on terrestrial salamanders in northern hardwood forests

Treesearch

Daniel J. Hocking; Kimberly J. Babbitt; Mariko Yamasaki

2013-01-01

In forested ecosystems timber harvesting has the potential to emulate natural disturbances, thereby maintaining the natural communities adapted to particular disturbances. We compared the effects of even-aged (clearcut and patch cut) and uneven-aged (group cut, single-tree selection) timber management techniques with natural ice-storm damage and unmanipulated reference...

Laser Cutting Eliminates Nucleic Acid Cross-Contamination in Dried-Blood-Spot Processing

PubMed Central

Daza, Glenda; Chang, Ming; Coombs, Robert

2012-01-01

Dried blood spots (DBS) are useful for molecular assays but are prone to false positives from cross-contamination. In our malaria DBS assay, cross-contamination was encountered despite cleaning techniques suitable for HIV-1. We therefore developed a contact-free laser cutting system that effectively eliminated cross-contamination during DBS processing. PMID:23052309

Pressure mapping for sphere and half-sphere enhanced diamond anvil cells using synchrotron x-ray diffraction and fluorescence techniques

NASA Astrophysics Data System (ADS)

Liu, H.; Liu, L. L.; Cai, Z.; Shu, J.

2015-12-01

The measurement for equation of state (EoS) of materials under pressure conditions above 200 GPa is a long-standing challenging subject. Recently, second stage anvil, which was loaded inside the diamond anvil cell (DAC), had been reported by various groups. This method could generate pressure over 300 GPa, or above 600 GPa from the EoS measurement of Re metal between the tiny anvil or 2 half-spheres. Several alternative approaches, using ruby balls, or glassy carbon, or diamond, with single sphere, 2 half-spheres, or multi spheres geometry inside DAC, were tested. The NIST X-ray powder standard, ZnO was selected as pressure marker. Focused ion beam (FIB) was used to cut the half-sphere from diamond anvil top directly to avoid the difficulty of alignment. The synchrotron x-ray diffraction with fine beam size down to 100 nm using zone plate set-up was used to map the pressure gradient at the sphere or half-sphere zone inside DAC. The pressure could be boosted at center of sphere by up to 10 - 70 GPa at about 200 GPa conditions. From broken anvils, trace element analysis using fine focusing synchrotron x-ray fluorescence method revealed the potential anvil damage from FIB cutting the diamond anvil tip, which might decrease the strength of anvils. Fine touch from FIB cutting at final stage using low ion beam current is suggested.

The Bookmark Procedure for Setting Cut-Scores and Finalizing Performance Standards: Strengths and Weaknesses

ERIC Educational Resources Information Center

Lin, Jie

2006-01-01

The Bookmark standard-setting procedure was developed to address the perceived problems with the most popular method for setting cut-scores: the Angoff procedure (Angoff, 1971). The purposes of this article are to review the Bookmark procedure and evaluate it in terms of Berk's (1986) criteria for evaluating cut-score setting methods. The…

Method and apparatus for suppressing regenerative instability and related chatter in machine tools

DOEpatents

Segalman, Daniel J.; Redmond, James M.

2001-01-01

Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

Method and apparatus for suppressing regenerative instability and related chatter in machine tools

DOEpatents

Segalman, Daniel J.; Redmond, James M.

1999-01-01

Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

[Parallel virtual reality visualization of extreme large medical datasets].

PubMed

Tang, Min

2010-04-01

On the basis of a brief description of grid computing, the essence and critical techniques of parallel visualization of extreme large medical datasets are discussed in connection with Intranet and common-configuration computers of hospitals. In this paper are introduced several kernel techniques, including the hardware structure, software framework, load balance and virtual reality visualization. The Maximum Intensity Projection algorithm is realized in parallel using common PC cluster. In virtual reality world, three-dimensional models can be rotated, zoomed, translated and cut interactively and conveniently through the control panel built on virtual reality modeling language (VRML). Experimental results demonstrate that this method provides promising and real-time results for playing the role in of a good assistant in making clinical diagnosis.

Determination of laser cutting process conditions using the preference selection index method

NASA Astrophysics Data System (ADS)

Madić, Miloš; Antucheviciene, Jurgita; Radovanović, Miroslav; Petković, Dušan

2017-03-01

Determination of adequate parameter settings for improvement of multiple quality and productivity characteristics at the same time is of great practical importance in laser cutting. This paper discusses the application of the preference selection index (PSI) method for discrete optimization of the CO2 laser cutting of stainless steel. The main motivation for application of the PSI method is that it represents an almost unexplored multi-criteria decision making (MCDM) method, and moreover, this method does not require assessment of the considered criteria relative significances. After reviewing and comparing the existing approaches for determination of laser cutting parameter settings, the application of the PSI method was explained in detail. Experiment realization was conducted by using Taguchi's L27 orthogonal array. Roughness of the cut surface, heat affected zone (HAZ), kerf width and material removal rate (MRR) were considered as optimization criteria. The proposed methodology is found to be very useful in real manufacturing environment since it involves simple calculations which are easy to understand and implement. However, while applying the PSI method it was observed that it can not be useful in situations where there exist a large number of alternatives which have attribute values (performances) very close to those which are preferred.

Stretchable Kirigami Polyvinylidene Difluoride Thin Films for Energy Harvesting: Design, Analysis, and Performance

NASA Astrophysics Data System (ADS)

Hu, Nan; Chen, Dajing; Wang, Dong; Huang, Shicheng; Trase, Ian; Grover, Hannah M.; Yu, Xiaojiao; Zhang, John X. J.; Chen, Zi

2018-02-01

Kirigami, a modified form of origami which includes cutting, has been used to improve material stretchability and compliance. However, this technique is, so far, underexplored in patterning piezoelectric materials towards developing efficient and mechanically flexible thin-film energy generators. Motivated by existing kirigami-based applications, we introduce interdigitated cuts to polyvinylidene fluoride (PVDF) films to evaluate the effect on voltage generation and stretchability. Our results from theoretical analysis, numerical simulations, and experimental tests show that kirigami PVDF films exhibit an extended strain range while still maintaining significant voltage generation compared to films without cuts. Various cutting patterns are studied, and it is found that films with denser cuts have a larger voltage output. This kirigami design can enhance the properties of existing piezoelectric materials and help to integrate tunable PVDF generators into biomedical devices.

Chapter 12: Survey Design and Implementation for Estimating Gross Savings Cross-Cutting Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurnik, Charles W; Baumgartner, Robert

This chapter presents an overview of best practices for designing and executing survey research to estimate gross energy savings in energy efficiency evaluations. A detailed description of the specific techniques and strategies for designing questions, implementing a survey, and analyzing and reporting the survey procedures and results is beyond the scope of this chapter. So for each topic covered below, readers are encouraged to consult articles and books cited in References, as well as other sources that cover the specific topics in greater depth. This chapter focuses on the use of survey methods to collect data for estimating gross savingsmore » from energy efficiency programs.« less

An experimental system for coiled tubing partial underbalanced drilling (CT-PUBD) technique

NASA Astrophysics Data System (ADS)

Shi, H. Z.; Ji, Z. S.; Zhao, H. Q.; Chen, Z. L.; Zhang, H. Z.

2018-05-01

To improve the rate of penetration (ROP) in hard formations, a new high-speed drilling technique called Coiled Tubing Partial Underbalanced Drilling (CT-PUBD) is proposed. This method uses a rotary packer to realize an underbalanced condition near the bit by creating a micro-annulus and an overbalanced condition at the main part of the annulus. A new full-scale laboratory experimental system is designed and set up to study the hydraulic characteristics and drilling performance of this method. The system is composed of a drilling system, circulation system, and monitor system, including three key devices, namely, cuttings discharge device, rotary packer, and backflow device. The experimental results showed that the pressure loss increased linearly with the flow rate of the drilling fluid. The high drilling speed of CT-PUBD proved it a better drilling method than the conventional drilling. The experimental system may provide a fundamental basis for the research of CT-PUBD, and the results proved that this new method is feasible in enhancing ROP and guaranteeing the drilling safety.

Stress wave techniques for determining quality of dimensional lumber from switch ties

Treesearch

K. C. Schad; D. E. Kretschmann; K. A. McDonald; R. J. Ross; D. W. Green

1995-01-01

Researchers at the Forest Products Laboratory, USDA Forest Service, have been studying nondestructive techniques for evaluating the strength of wood. This report describes the results of a pilot study on using these techniques to determine the quality of large dimensional lumber cut from switch ties. First, pulse echo and dynamic (transverse vibration) techniques were...

The innovation of cryo-SEM freeze-fracturing methodology demonstrated on high pressure frozen biofilm.

PubMed

Hrubanova, Kamila; Nebesarova, Jana; Ruzicka, Filip; Krzyzanek, Vladislav

2018-07-01

In this study we present an innovative method for the preparation of fully hydrated samples of microbial biofilms of cultures Staphylococcus epidermidis, Candida parapsilosis and Candida albicans. Cryo-scanning electron microscopy (cryo-SEM) and high-pressure freezing (HPF) rank among cutting edge techniques in the electron microscopy of hydrated samples such as biofilms. However, the combination of these techniques is not always easily applicable. Therefore, we present a method of combining high-pressure freezing using EM PACT2 (Leica Microsystems), which fixes hydrated samples on small sapphire discs, with a high resolution SEM equipped with the widely used cryo-preparation system ALTO 2500 (Gatan). Using a holder developed in house, a freeze-fracturing technique was applied to image and investigate microbial cultures cultivated on the sapphire discs. In our experiments, we focused on the ultrastructure of the extracellular matrix produced during cultivation and the relationships among microbial cells in the biofilm. The main goal of our investigations was the detailed visualization of areas of the biofilm where the microbial cells adhere to the substrate/surface. We show the feasibility of this technique, which is clearly demonstrated in experiments with various freeze-etching times. Copyright © 2018 Elsevier Ltd. All rights reserved.

Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mai, Sebastian; Marquetand, Philipp; González, Leticia

2014-08-21

An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbitmore » coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.« less

Identification of cutting force coefficients in machining process considering cutter vibration

NASA Astrophysics Data System (ADS)

Yao, Qi; Luo, Ming; Zhang, Dinghua; Wu, Baohai

2018-03-01

Among current cutting force models, cutting force coefficients still are the foundation of predicting calculation combined with consideration of geometry engagement variation, equipment characteristics, material properties and so on. Attached with unimpeachable significance, the traditional and some novel identification methods of cutting force coefficient are still faced with trouble, including repeated onerous work, over ideal measuring condition, variation of value due to material divergence, interference from measuring units. To utilize the large amount of data from real manufacturing section, enlarge data sources and enrich cutting data base for former prediction task, a novel identification method is proposed by considering stiffness properties of the cutter-holder-spindle system in this paper. According to previously proposed studies, the direct result of cutter vibration is the form of dynamic undeformed chip thickness. This fluctuation is considered in two stages of this investigation. Firstly, a cutting force model combined with cutter vibration is established in detailed way. Then, on the foundation of modeling, a novel identification method is developed, in which the dynamic undeformed chip thickness could be obtained by using collected data. In a carefully designed experiment procedure, the reliability of model is validated by comparing predicted and measured results. Under different cutting condition and cutter stiffness, data is collected for the justification of identification method. The results showed divergence in calculated coefficients is acceptable confirming the possibility of accomplishing targets by applying this new method. In discussion, the potential directions of improvement are proposed.

Speeding Up the Bilateral Filter: A Joint Acceleration Way.

PubMed

Dai, Longquan; Yuan, Mengke; Zhang, Xiaopeng

2016-06-01

Computational complexity of the brute-force implementation of the bilateral filter (BF) depends on its filter kernel size. To achieve the constant-time BF whose complexity is irrelevant to the kernel size, many techniques have been proposed, such as 2D box filtering, dimension promotion, and shiftability property. Although each of the above techniques suffers from accuracy and efficiency problems, previous algorithm designers were used to take only one of them to assemble fast implementations due to the hardness of combining them together. Hence, no joint exploitation of these techniques has been proposed to construct a new cutting edge implementation that solves these problems. Jointly employing five techniques: kernel truncation, best N-term approximation as well as previous 2D box filtering, dimension promotion, and shiftability property, we propose a unified framework to transform BF with arbitrary spatial and range kernels into a set of 3D box filters that can be computed in linear time. To the best of our knowledge, our algorithm is the first method that can integrate all these acceleration techniques and, therefore, can draw upon one another's strong point to overcome deficiencies. The strength of our method has been corroborated by several carefully designed experiments. In particular, the filtering accuracy is significantly improved without sacrificing the efficiency at running time.

Optimization and Analysis of Laser Beam Machining Parameters for Al7075-TiB2 In-situ Composite

NASA Astrophysics Data System (ADS)

Manjoth, S.; Keshavamurthy, R.; Pradeep Kumar, G. S.

2016-09-01

The paper focuses on laser beam machining (LBM) of In-situ synthesized Al7075-TiB2 metal matrix composite. Optimization and influence of laser machining process parameters on surface roughness, volumetric material removal rate (VMRR) and dimensional accuracy of composites were studied. Al7075-TiB2 metal matrix composite was synthesized by in-situ reaction technique using stir casting process. Taguchi's L9 orthogonal array was used to design experimental trials. Standoff distance (SOD) (0.3 - 0.5mm), Cutting Speed (1000 - 1200 m/hr) and Gas pressure (0.5 - 0.7 bar) were considered as variable input parameters at three different levels, while power and nozzle diameter were maintained constant with air as assisting gas. Optimized process parameters for surface roughness, volumetric material removal rate (VMRR) and dimensional accuracy were calculated by generating the main effects plot for signal noise ratio (S/N ratio) for surface roughness, VMRR and dimensional error using Minitab software (version 16). The Significant of standoff distance (SOD), cutting speed and gas pressure on surface roughness, volumetric material removal rate (VMRR) and dimensional error were calculated using analysis of variance (ANOVA) method. Results indicate that, for surface roughness, cutting speed (56.38%) is most significant parameter followed by standoff distance (41.03%) and gas pressure (2.6%). For volumetric material removal (VMRR), gas pressure (42.32%) is most significant parameter followed by cutting speed (33.60%) and standoff distance (24.06%). For dimensional error, Standoff distance (53.34%) is most significant parameter followed by cutting speed (34.12%) and gas pressure (12.53%). Further, verification experiments were carried out to confirm performance of optimized process parameters.

Smart Cutting Tools and Smart Machining: Development Approaches, and Their Implementation and Application Perspectives

NASA Astrophysics Data System (ADS)

Cheng, Kai; Niu, Zhi-Chao; Wang, Robin C.; Rakowski, Richard; Bateman, Richard

2017-09-01

Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultraprecision and micro manufacturing purposes. Implementation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation techniques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algorithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in-process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) application exemplars on adaptive smart machining.

Logging costs and cutting methods in young-growth ponderosa pine in California

Treesearch

Philip M. McDonald; William A. Atkinson; Dale O. Hall

1969-01-01

Mixed-conifer stands at the Challenge Experimental Forest, Calif., were cut to four specifications: seed-tree, group selection, single tree selection, and clearcut. Logging costs and production rates were compared and evaluated. Cutting method had little effect on felling or skidding production; felling ranged from 1,802 to 2,019 bd ft per hour, and skidding from 3,138...

Regeneration Development Across a Range of Reproduction Cutting Methods in Shortleaf Pine and Pine-Hardwood Stands in the Interior Highlands

Treesearch

James M. Guldin; James B. Baker; Michael G. Shelton

2004-01-01

Abstract - Density, milacre stocking, and height of shortleaf pine ( Pinus echinata Mill.) regeneration under 13 reproduction cutting methods were measured after 5 growing seasons across a range of reproduction cutting treatments in shortleaf pine and pine-hardwood stands in the Interior Highlands of Arkansas and Oklahoma. A subset...

Forcing the Tissue

Treesearch

John E. Preece; J. W. Van Sambeek; Paul H. Henry; James Zaczek

2002-01-01

Many woody shrubs and trees are propagated by rooting green, leafy cuttings (softwood or semihardwood) because of poor rooting response from dormant hardwood cuttings. However, this method limits cutting propagation to a short period each year. As a group of scientists, we've developed a system that allows for production of softwood cuttings during the dormant...

Sequential segmental terminal lenticular side-cut dissection for safe and effective small-incision lenticule extraction in thin lenticules.

PubMed

Jacob, Soosan; Agarwal, Amar; Mazzotta, Cosimo; Agarwal, Athiya; Raj, John Michael

2017-04-01

Small-incision lenticule extraction may be associated with complications such as partial lenticular dissection, torn lenticule, lenticular adherence to cap, torn cap, and sub-cap epithelial ingrowth, some of which are more likely to occur during low-myopia corrections. We describe sequential segmental terminal lenticular side-cut dissection to facilitate minimally traumatic and smooth lenticular extraction. Anterior lamellar dissection is followed by central posterior lamellar dissection, leaving a thin peripheral rim and avoiding the lenticular side cut. This is followed by sequential segmental dissection of the lenticular side cut in a manner that fixates the lenticule and provides sufficient resistance for smooth and complete dissection of the posterior lamellar cut without undesired movements of the lenticule. The technique is advantageous in thin lenticules, where the risk for complications is high, but can also be used in thick lenticular dissection using wider sweeps to separate the lenticular side cut sequentially. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Selected nutrient contents, fatty acid composition, including conjugated linoleic acid, and retention values in separable lean from lamb rib loins as affected by external fat and cooking method.

PubMed

Badiani, Anna; Montellato, Lara; Bochicchio, Davide; Anfossi, Paola; Zanardi, Emanuela; Maranesi, Magda

2004-08-11

Proximate composition and fatty acid profile, conjugated linoleic acid (CLA) isomers included, were determined in separable lean of raw and cooked lamb rib loins. The cooking methods compared, which were also investigated for cooking yields and true nutrient retention values, were dry heating of fat-on cuts and moist heating of fat-off cuts; the latter method was tested as a sort of dietetic approach against the more traditional former type. With significantly (P < 0.05) lower cooking losses, dry heating of fat-on rib-loins produced slightly (although only rarely significantly) higher retention values for all of the nutrients considered, including CLA isomers. On the basis of the retention values obtained, both techniques led to a minimum migration of lipids into the separable lean, which was higher (P < 0.05) in dry heating than in moist heating, and was characterized by the prevalence of saturated and monounsaturated fatty acids. On the whole, the response to cooking of the class of CLA isomers (including that of the nutritionally most important isomer cis-9,trans-11) was more similar to that of the monounsaturated than the polyunsaturated fatty acids.

The impact of lignin downregulation on alfalfa yield, chemical composition, and in vitro gas production.

PubMed

Getachew, Girma; Laca, Emilio A; Putnam, Daniel H; Witte, Dave; McCaslin, Mark; Ortega, Kara P; DePeters, Edward J

2018-02-06

Lignin is a complex, phenolic polymer found in plant cell walls that is essential for mechanical support, water and mineral transport, and defense in vascular plants. Over ten different enzymes play a role in the synthesis of lignin in plants. Suppression of any one enzyme or combinations of these enzymes may change the concentration and composition of lignin in the genetically transformed plants. Two lines of alfalfa that were downregulated for caffeoyl coenzyme A O-methyltransferase were used to assess the impact of lignin downregulation on chemical composition and fermentation rate and extent using an in vitro gas production technique. A total of 64 samples consisting of two reduced lignin (RL) and two controls (CL), four field replicates, two cutting intervals (CIs; 28 and 35 days), and two cuts (Cut-1 and Cut-3) were used. No differences were detected in yield, crude protein, neutral detergent fiber (aNDF), and acid detergent fiber between the lines when harvested at the 28-day CI. The acid detergent lignin (ADL) concentration in RL alfalfa lines was significantly (P < 0.001) lower than in the CL. In alfalfa harvested at the 35-day CI, the RL alfalfa resulted in lower (P < 0.001) yield than CL. RL alfalfa lines had 24% and 22% lower (P < 0.001) ADL in Cut-1 and Cut-3 respectively than CL lines. The in vitro dry matter digestibility and aNDF digestibility (both as determined by the near-infrared reflectance method) were greater (P < 0.001) in RL than in CL lines harvested at the 35-day CI. In alfalfa harvested at the 35-day CI, extent of in vitro gas production and metabolizable energy content were greater in RL than in CL alfalfa. RL lines had 3.8% indigestible aNDF per unit ADL, whereas CL had 3.4% (P < 0.01). The positive effect of lignin downregulation was more pronounced when intervals between harvests were longer (35-day CI compared with the 28-day CI). Lignin downregulation in alfalfa offers an opportunity to extend harvesting time (CI) for higher yield without compromising the nutritional quality of the alfalfa forage for dairy and livestock feeding. However, the in vitro results reported here warrant further study using in vivo methods. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Monosomy 3 by FISH in uveal melanoma: variability in techniques and results.

PubMed

Aronow, Mary; Sun, Yang; Saunthararajah, Yogen; Biscotti, Charles; Tubbs, Raymond; Triozzi, Pierre; Singh, Arun D

2012-09-01

Tumor monosomy 3 confers a poor prognosis in patients with uveal melanoma. We critically review the techniques used for fluorescence in situ hybridization (FISH) detection of monosomy 3 in order to assess variability in practice patterns and to explain differences in results. Significant variability that has likely affected reported results was found in tissue sampling methods, selection of FISH probes, number of cells counted, and the cut-off point used to determine monosomy 3 status. Clinical parameters and specific techniques employed to report FISH results should be specified so as to allow meta-analysis of published studies. FISH-based detection of monosomy 3 in uveal melanoma has not been performed in a standardized manner, which limits conclusions regarding its clinical utility. FISH is a widely available, versatile technology, and when performed optimally has the potential to be a valuable tool for determining the prognosis of uveal melanoma. Copyright © 2012 Elsevier Inc. All rights reserved.

Aseptic minimum volume vitrification technique for porcine parthenogenetically activated blastocyst.

PubMed

Lin, Lin; Yu, Yutao; Zhang, Xiuqing; Yang, Huanming; Bolund, Lars; Callesen, Henrik; Vajta, Gábor

2011-01-01

Minimum volume vitrification may provide extremely high cooling and warming rates if the sample and the surrounding medium contacts directly with the respective liquid nitrogen and warming medium. However, this direct contact may result in microbial contamination. In this work, an earlier aseptic technique was applied for minimum volume vitrification. After equilibration, samples were loaded on a plastic film, immersed rapidly into factory derived, filter-sterilized liquid nitrogen, and sealed into sterile, pre-cooled straws. At warming, the straw was cut, the filmstrip was immersed into a 39 degree C warming medium, and the sample was stepwise rehydrated. Cryosurvival rates of porcine blastocysts produced by parthenogenetical activation did not differ from control, vitrified blastocysts with Cryotop. This approach can be used for minimum volume vitrification methods and may be suitable to overcome the biological dangers and legal restrictions that hamper the application of open vitrification techniques.

Technology development of fabrication techniques for advanced solar dynamic concentrators

NASA Technical Reports Server (NTRS)

Richter, Scott W.

1991-01-01

The objective of the advanced concentrator program is to develop the technology that will lead to lightweight, highly reflective, accurate, scaleable, and long lived space solar dynamic concentrators. The advanced concentrator program encompasses new and innovative concepts, fabrication techniques, materials selection, and simulated space environmental testing. Fabrication techniques include methods of fabricating the substrates and coating substrate surfaces to produce high quality optical surfaces, acceptable for further coating with vapor deposited optical films. The selected materials to obtain a high quality optical surface include microsheet glass and Eccocoat EP-3 epoxy, with DC-93-500 selected as a candidate silicone adhesive and levelizing layer. The following procedures are defined: cutting, cleaning, forming, and bonding microsheet glass. Procedures are also defined for surface cleaning, and EP-3 epoxy application. The results and analyses from atomic oxygen and thermal cycling tests are used to determine the effects of orbital conditions in a space environment.

Dosimetric changes with computed tomography automatic tube-current modulation techniques.

PubMed

Spampinato, Sofia; Gueli, Anna Maria; Milone, Pietro; Raffaele, Luigi Angelo

2018-04-06

The study is aimed at a verification of dose changes for a computed tomography automatic tube-current modulation (ATCM) technique. For this purpose, anthropomorphic phantom and Gafchromic ® XR-QA2 films were used. Radiochromic films were cut according to the shape of two thorax regions. The ATCM algorithm is based on noise index (NI) and three exam protocols with different NI were chosen, of which one was a reference. Results were compared with dose values displayed by the console and with Poisson statistics. The information obtained with radiochromic films has been normalized with respect to the NI reference value to compare dose percentage variations. Results showed that, on average, the information reported by the CT console and calculated values coincide with measurements. The study allowed verification of the dose information reported by the CT console for an ATCM technique. Although this evaluation represents an estimate, the method can be a starting point for further studies.

Synthesis, growth and characterization of 3-nitroacetanilide—A new organic nonlinear optical crystal by Bridgman technique

NASA Astrophysics Data System (ADS)

Lenin, M.; Ramasamy, P.

2008-10-01

Single crystals of 3-nitroacetanilide, an organic nonlinear optical material has been grown by the Bridgman-Stockbarger method. The single crystal X-ray diffraction (XRD) data revealed the noncentrosymmetric crystal structure, which is an essential criterion for second harmonic generation. The crystalline nature of the grown crystals was confirmed using powder XRD techniques. The functional group of the compound is identified by FTIR spectrum. The thermal stability and its tendency to grow as single crystal in solution and in melt have been identified for the new title compound. The UV-vis spectrum of mNAA shows the lower optical cut off at 400 nm and was transparent in the visible region. The second harmonic generation efficiency was found using Kurtz powder technique. The dielectric constant and dielectric loss of the crystal were measured as a function of frequency and temperature, and the results are discussed.

Applying and advancing behavior change theories and techniques in the context of a digital health revolution: Proposals for more effectively realizing untapped potential

PubMed Central

Moller, Arlen C.; Merchant, Gina; Conroy, David E.; West, Robert; Hekler, Eric B.; Kugler, Kari C.; Michie, Susan

2017-01-01

As more behavioral health interventions move from traditional to digital platforms, the application of evidence-based theories and techniques may be doubly advantageous. First, it can expedite digital health intervention development, improving efficacy, and increasing reach. Second, moving behavioral health interventions to digital platforms presents researchers with novel (potentially paradigm shifting) opportunities for advancing theories and techniques. In particular, the potential for technology to revolutionize theory refinement is made possible by leveraging the proliferation of “real-time” objective measurement and “big data” commonly generated and stored by digital platforms. Much more could be done to realize this potential. This paper offers proposals for better leveraging the potential advantages of digital health platforms, and reviews three of the cutting edge methods for doing so: optimization designs, dynamic systems modeling, and social network analysis. PMID:28058516

Evaluation of the performance during hard turning of OHNS steel with minimal cutting fluid application and its comparison with minimum quantity lubrication

NASA Astrophysics Data System (ADS)

Raj, Anil; Wins, K. Leo Dev; Varadarajan, A. S.

2016-09-01

Cutting fluid application plays a significant role in the manufacturing industries that acts as a coolant as well as a lubricant. The conventional flood cooling application of cutting fluids not only increases the production cost on account of the expenses involved in procurement, storage and disposal but also creates serious environmental and health hazards. In order to overcome these negative effects, techniques like Minimum quantity lubrication (MQL) and Minimal Cutting fluid application (MCFA) have increasingly found their way into the area of metal cutting and have already been established as an alternative to conventional wet machining. This paper investigates the effect of minimal Cutting fluid application (MCFA) which involves application of high velocity pulsing jet of proprietary cutting fluids at the contact zones using a special fluid application system. During hard turning of oil hardened non shrinkable steel (OHNS) on cutting temperature and tool wear and to compare the performance with Minimum quantity lubrication (MQL) assisted hard turning in which cutting fluid is carried in a high velocity stream of air. An attempt was also made to compare the performance during Turning with MCFA and MQL application with conventional wet and dry turning by analysing the tool wear pattern using SEM images.

CO 2 laser cutting of MDF . 2. Estimation of power distribution

NASA Astrophysics Data System (ADS)

Ng, S. L.; Lum, K. C. P.; Black, I.

2000-02-01

Part 2 of this paper details an experimentally-based method to evaluate the power distribution for both CW and PM cutting. Variations in power distribution with different cutting speeds, material thickness and pulse ratios are presented. The paper also provides information on both the cutting efficiency and absorptivity index for MDF, and comments on the beam dispersion characteristics after the cutting process.

Long gap esophageal atresia: lengthening technique and primary anastomosis.

PubMed

Hadidi, Ahmed T; Hosie, Stuart; Waag, Karl-Ludwig

2007-10-01

The treatment of long gap esophageal atresia remains a major surgical challenge. The authors describe a modification of a lengthening technique based on tissue expansion to avoid sutures cutting through the esophagus. Between January 2004 and August 2006, 4 patients did not respond to stretching, and underwent this modified esophageal lengthening technique using silastic tubes. RESULTS AND FOLLOW-UP: All infants recovered and have an intact esophagus. All infants developed gastroesophageal reflux. Thal antireflux procedure was performed in the first infant. The other 3 patients were managed conservatively. Follow-up ranged between 6 and 34 months. The tissue expansion principle can be successfully applied in the esophagus through external traction. Silastic tube fixation at esophageal ends may help to apply even traction and avoid sutures cutting through the esophageal tissue.

Nanofluid as coolant for grinding process: An overview

NASA Astrophysics Data System (ADS)

Kananathan, J.; Samykano, M.; Sudhakar, K.; Subramaniam, S. R.; Selavamani, S. K.; Manoj Kumar, Nallapaneni; Keng, Ngui Wai; Kadirgama, K.; Hamzah, W. A. W.; Harun, W. S. W.

2018-04-01

This paper reviews the recent progress and applications of nanoparticles in lubricants as a coolant (cutting fluid) for grinding process. The role of grinding machining in manufacturing and the importance of lubrication fluids during material removal are discussed. In grinding process, coolants are used to improve the surface finish, wheel wear, flush the chips and to reduce the work-piece thermal deformation. The conventional cooling technique, i.e., flood cooling delivers a large amount of fluid and mist which hazardous to the environment and humans. Industries are actively looking for possible ways to reduce the volume of coolants used in metal removing operations due to the economical and ecological impacts. Thus as an alternative, an advanced cooling technique known as Minimum Quantity Lubrication (MQL) has been introduced to the enhance the surface finish, minimize the cost, to reduce the environmental impacts and to reduce the metal cutting fluid consumptions. Nanofluid is a new-fangled class of fluids engineered by dispersing nanometre-size solid particles into base fluids such as water, lubrication oils to further improve the properties of the lubricant or coolant. In addition to advanced cooling technique review, this paper also reviews the application of various nanoparticles and their performance in grinding operations. The performance of nanoparticles related to the cutting forces, surface finish, tool wear, and temperature at the cutting zone are briefly reviewed. The study reveals that the excellent properties of the nanofluid can be beneficial in cooling and lubricating application in the manufacturing process.

An improved FIB sample preparation technique for site-specific plan-view specimens: A new cutting geometry.

PubMed

Li, Chen; Habler, Gerlinde; Baldwin, Lisa C; Abart, Rainer

2018-01-01

Focused ion beam (FIB) sample preparation technique in plan-view geometry allows direct correlations of the atomic structure study via transmission electron microscopy with micrometer-scale property measurements. However, one main technical difficulty is that a large amount of material must be removed underneath the specimen. Furthermore, directly monitoring the milling process is difficult unless very large material volumes surrounding the TEM specimen site are removed. In this paper, a new cutting geometry is introduced for FIB lift-out sample preparation with plan-view geometry. Firstly, an "isolated" cuboid shaped specimen is cut out, leaving a "bridge" connecting it with the bulk material. Subsequently the two long sides of the "isolated" cuboid are wedged, forming a triangular prism shape. A micromanipulator needle is used for in-situ transfer of the specimen to a FIB TEM grid, which has been mounted parallel with the specimen surface using a simple custom-made sample slit. Finally, the grid is transferred to the standard FIB grid holder for final thinning with standard procedures. This new cutting geometry provides clear viewing angles for monitoring the milling process, which solves the difficulty of judging whether the specimen has been entirely detached from the bulk material, with the least possible damage to the surrounding materials. With an improved success rate and efficiency, this plan-view FIB lift-out specimen preparation technique should have a wide application for material science. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Sampling tree tops by helicopter...special pole pruner cuts branchlets

Treesearch

John F. Wear; Robert G. Winterfeld

1966-01-01

A new technique for sampling tops of tall Douglas-fir trees by using a special pole pruner from a helicopter has been developed and field-tested. Thee pole pruner cuts and holds a branchlet. Foliage samples collected will be compared by spectral analysis to show the type of aerial imagery that best differentiates healthy trees from those attacked by root rot.

An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming.

PubMed

Wang, Xiao; Li, Cong; Ma, Youjuan; Shen, Zongbao; Sun, Xianqing; Sha, Chaofei; Gao, Shuai; Li, Liyin; Liu, Huixia

2016-07-13

This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper foils) and dissimilar material combination (1060 pure aluminum foils and 304 stainless steel foils) were successfully achieved. The effect of laser energy on the interlock and minimum thickness of upper foils was investigated. In addition, the mechanical strength of different material combinations joined by micro clinching with cutting was measured in single lap shearing tests. According to the achieved results, this novel technique is more suitable for material combinations where the upper foil is thicker than lower foil. With the increase of laser energy, the interlock increased while the minimum thickness of upper foil decreased gradually. The shear strength of 1060 pure aluminum foils and 304 stainless steel foils combination was three times as large as that of 1060 pure aluminum foils and annealed copper foils combination.

A modified method using a two-port approach for accessing the hilar vasculature without transferring an endostapler from camera port to utility port during thoracoscopic right upper lobectomy.

PubMed

Jiao, W; Zhao, Y; Xuan, Y; Wang, M

2015-02-01

For thoracoscopic upper lobectomies, most cutting endostaplers must be inserted through the camera port when using a two-port approach. Access to the hilar vasculature through only the utility port remains a challenge. In this study, we describe a procedure to access the hilar vasculature without transferring the endostapler site during a thoracoscopic right upper lobectomy. A 2.5-cm utility anterior incision was made in the fourth intercostal space. The posterior mediastinal visceral pleura were dissected to expose the posterior portion of the right upper bronchus and the anterior trunk of the right pulmonary artery. The pleura over the right hilar vasculature were then peeled with an electrocoagulation hook. The anterior trunk of the right pulmonary artery was then transected with a cutting endostapler through the utility port firstly. This crucial maneuver allowed the endostapler access to the right upper lobe pulmonary vein. The hilar structures were then easily handled in turn. This novel technique was performed successfully in 32 patients, with no perioperative deaths. The average operation time was 120.6 min (range 75-180 min). This novel technique permits effective control of the hilar vessels through the utility port, enabling simple, safe, quick and effective resection.

Anisotropy in thermal conductivity of graphite flakes–SiC{sub p}/matrix composites: Implications in heat sinking design for thermal management applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Molina, J.M., E-mail: jmmj@ua.es; Departamento de Física Aplicada, Universidad de Alicante, Ap. 99, E-03080 Alicante; Departamento de Química Inorgánica, Universidad de Alicante, Ap. 99, | E-03080 Alicante

2015-11-15

Within the frame of heat dissipation for electronics, a very interesting family of anisotropic composite materials, fabricated by liquid infiltration of a matrix into preforms of oriented graphite flakes and SiC particles, has been recently proposed. Aiming to investigate the implications of the inherent anisotropy of these composites on their thermal conductivity, and hence on their potential applications, materials with matrices of Al–12 wt.% Si alloy and epoxy polymer have been fabricated. Samples have been cut at a variable angle with respect to the flakes plane and thermal conductivity has been measured by means of two standard techniques, namely, steadymore » state technique and laser flash method. Experimental results are presented and discussed in terms of current models, from which important technological implications for heat sinking design can be derived. - Highlights: • Anisotropy in thermal conductivity of graphite flakes-based composites is evaluated. • Samples are cut in a direction forming a variable angle with the oriented flakes. • For angles 0° and 90°, thermal conductivity does not depend on sample geometry. • For intermediate angles, thermal conductivity strongly depends on sample geometry. • “Thin” samples must be thicker than 600 μm, “thick” samples must be encapsulated.« less

Cavity formation and surface modeling of laser milling process under a thin-flowing water layer

NASA Astrophysics Data System (ADS)

Tangwarodomnukun, Viboon

2016-11-01

Laser milling process normally involves a number of laser scans over a workpiece to selectively remove the material and then to form cavities with shape and dimensions required. However, this process adversely causes a heat accumulation in work material, which can in turn damage the laser-milled area and vicinity in terms of recast deposition and change of material properties. Laser milling process performing in a thin-flowing water layer is a promising method that can overcome such damage. With the use of this technique, water can flush away the cut debris and at the same time cool the workpiece during the ablation. To understand the potential of this technique for milling application, the effects of process parameters on cavity dimensions and surface roughness were experimentally examined in this study. Titanium sheet was used as a workpiece to be milled by a nanosecond pulse laser under different water flow velocities. A smooth and uniform cut feature can be obtained when the metal was ablated under the high laser pulse frequency and high water flow velocity. Furthermore, a surface model based on the energy balance was developed in this study to predict the cavity profile and surface roughness. By comparing to the experiments, the predicted profiles had a good agreement with the measured ones.

High resolution beamforming on large aperture vertical line arrays: Processing synthetic data

NASA Astrophysics Data System (ADS)

Tran, Jean-Marie Q.; Hodgkiss, William S.

1990-09-01

This technical memorandum studies the beamforming of large aperture line arrays deployed vertically in the water column. The work concentrates on the use of high resolution techniques. Two processing strategies are envisioned: (1) full aperture coherent processing which offers in theory the best processing gain; and (2) subaperture processing which consists in extracting subapertures from the array and recombining the angular spectra estimated from these subarrays. The conventional beamformer, the minimum variance distortionless response (MVDR) processor, the multiple signal classification (MUSIC) algorithm and the minimum norm method are used in this study. To validate the various processing techniques, the ATLAS normal mode program is used to generate synthetic data which constitute a realistic signals environment. A deep-water, range-independent sound velocity profile environment, characteristic of the North-East Pacific, is being studied for two different 128 sensor arrays: a very long one cut for 30 Hz and operating at 20 Hz; and a shorter one cut for 107 Hz and operating at 100 Hz. The simulated sound source is 5 m deep. The full aperture and subaperture processing are being implemented with curved and plane wavefront replica vectors. The beamforming results are examined and compared to the ray-theory results produced by the generic sonar model.

Electro-chemical grinding

NASA Technical Reports Server (NTRS)

Feagans, P. L.

1972-01-01

Electro-chemical grinding technique has rotation speed control, constant feed rates, and contour control. Hypersonic engine parts of nickel alloys can be almost 100% machined, keeping tool pressure at virtual zero. Technique eliminates galling and permits constant surface finish and burr-free interrupted cutting.

Surface dimpling on rotating work piece using rotation cutting tool

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhapkar, Rohit Arun; Larsen, Eric Richard

A combined method of machining and applying a surface texture to a work piece and a tool assembly that is capable of machining and applying a surface texture to a work piece are disclosed. The disclosed method includes machining portions of an outer or inner surface of a work piece. The method also includes rotating the work piece in front of a rotating cutting tool and engaging the outer surface of the work piece with the rotating cutting tool to cut dimples in the outer surface of the work piece. The disclosed tool assembly includes a rotating cutting tool coupledmore » to an end of a rotational machining device, such as a lathe. The same tool assembly can be used to both machine the work piece and apply a surface texture to the work piece without unloading the work piece from the tool assembly.« less

Poster – 39: Using Optical Scanner and 3D Printer Technology to Create Lead Shielding for Radiotherapy of Facial Skin Cancer with Low Energy Photons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rickey, Daniel; Leylek, Ahmet; Dubey, Arbind

Purpose: Treatment of skin cancers of the face using orthovoltage radiotherapy often requires lead shielding. However, creating a lead shield can be difficult because the face has complex and intricate contours. The traditional process involved creating a plaster mould of the patient’s face can be difficult for patients. Our goal was to develop an improved process by using an optical scanner and 3D printer technology. Methods: The oncologist defined the treatment field by drawing on each patient’s skin. Three-dimensional images were acquired using a consumer-grade optical scanner. A 3D model of each patient’s face was processed with mesh editing softwaremore » before being printed on a 3D printer. Using a hammer, a 3 mm thick layer of lead was formed to closely fit the contours of the model. A hole was then cut out to define the field. Results: The lead shields created were remarkably accurate and fit the contours of the patients. The hole defining the field exposed only a minimally sized site to be exposed to radiation, while the rest of the face was protected. It was easy to obtain perfect symmetry for the definition of parallel opposed beams. Conclusion: We are routinely using this technique to build lead shielding that wraps around the patient as an alternative to cut-outs. We also use it for treatment of the tip of the nose using a parallel opposed pair beams with a wax nose block. We found this technique allows more accurate delineation of the cut-out and a more reproducible set-up.« less

Paraffin tissue microarrays constructed with a cutting board and cutting board arrayer.

PubMed

Vogel, Ulrich Felix

2010-05-01

Paraffin tissue microarrays (PTMAs) are blocks of paraffin containing up to 1300 paraffin tissue core biopsies (PTCBs). Normally, these PTCBs are punched from routine paraffin tissue blocks, which contain tissues of differing thicknesses. Therefore, the PTCBs are of different lengths. In consequence, the sections of the deeper portions of the PTMA do not contain all of the desired PTCBs. To overcome this drawback, cutting boards were constructed from panels of plastic with a thickness of 4 mm. Holes were drilled into the plastic and filled completely with at least one PTCB per hole. After being trimmed to a uniform length of 4 mm, these PTCBs were pushed from the cutting board into corresponding holes in a recipient block by means of a plate with steel pins. Up to 1000 sections per PTMA were cut without any significant loss of PTCBs, thereby increasing the efficacy of the PTMA technique.

Fractography of composite delamination

NASA Technical Reports Server (NTRS)

Bascom, W. D.

1989-01-01

Delamination is a major failure mode of carbon fiber organic matrix composites. It can occur under a variety of loading conditions. Efforts to develop predictive models of the delamination of carbon fiber composites are hampered by a lack of information about the micromechanics of impact damage and delamination growth. Crack formation and propagation in these materials cannot be observed in sufficient detail to determine micro-damage using currently available nondestructive methods such as acoustic backscattering or x ray imaging. Consequently, destructive methods are required. Delamination of composites in Mode I, Mode II and after low energy impact loads were investigated using metallographic techniques of potting the failed specimens, sectioning and examining the cut sections for damage modes.

Flow visualization over a thick blunt trailing-edge airfoil with base cavity at low Reynolds numbers using PIV technique.

PubMed

Taherian, Gholamhossein; Nili-Ahmadabadi, Mahdi; Karimi, Mohammad Hassan; Tavakoli, Mohammad Reza

2017-01-01

In this study, the effect of cutting the end of a thick airfoil and adding a cavity on its flow pattern is studied experimentally using PIV technique. First, by cutting 30% chord length of the Riso airfoil, a thick blunt trialing-edge airfoil is generated. The velocity field around the original airfoil and the new airfoil is measured by PIV technique and compared with each other. Then, adding two parallel plates to the end of the new airfoil forms the desired cavity. Continuous measurement of unsteady flow velocity over the Riso airfoil with thick blunt trailing edge and base cavity is the most important innovation of this research. The results show that cutting off the end of the airfoil decreases the wake region behind the airfoil, when separation occurs. Moreover, adding a cavity to the end of the thickened airfoil causes an increase in momentum and a further decrease in the wake behind the trailing edge that leads to a drag reduction in comparison with the thickened airfoil without cavity. Furthermore, using cavity decreases the Strouhal number and vortex shedding frequency.

An Eulerian time filtering technique to study large-scale transient flow phenomena

NASA Astrophysics Data System (ADS)

Vanierschot, Maarten; Persoons, Tim; van den Bulck, Eric

2009-10-01

Unsteady fluctuating velocity fields can contain large-scale periodic motions with frequencies well separated from those of turbulence. Examples are the wake behind a cylinder or the processing vortex core in a swirling jet. These turbulent flow fields contain large-scale, low-frequency oscillations, which are obscured by turbulence, making it impossible to identify them. In this paper, we present an Eulerian time filtering (ETF) technique to extract the large-scale motions from unsteady statistical non-stationary velocity fields or flow fields with multiple phenomena that have sufficiently separated spectral content. The ETF method is based on non-causal time filtering of the velocity records in each point of the flow field. It is shown that the ETF technique gives good results, similar to the ones obtained by the phase-averaging method. In this paper, not only the influence of the temporal filter is checked, but also parameters such as the cut-off frequency and sampling frequency of the data are investigated. The technique is validated on a selected set of time-resolved stereoscopic particle image velocimetry measurements such as the initial region of an annular jet and the transition between flow patterns in an annular jet. The major advantage of the ETF method in the extraction of large scales is that it is computationally less expensive and it requires less measurement time compared to other extraction methods. Therefore, the technique is suitable in the startup phase of an experiment or in a measurement campaign where several experiments are needed such as parametric studies.

Extension of the Time-Spectral Approach to Overset Solvers for Arbitrary Motion

NASA Technical Reports Server (NTRS)

Leffell, Joshua Isaac; Murman, Scott M.; Pulliam, Thomas H.

2012-01-01

Forced periodic flows arise in a broad range of aerodynamic applications such as rotorcraft, turbomachinery, and flapping wing configurations. Standard practice involves solving the unsteady flow equations forward in time until the initial transient exits the domain and a statistically stationary flow is achieved. It is often required to simulate through several periods to remove the initial transient making unsteady design optimization prohibitively expensive for most realistic problems. An effort to reduce the computational cost of these calculations led to the development of the Harmonic Balance method [1, 2] which capitalizes on the periodic nature of the solution. The approach exploits the fact that forced temporally periodic flow, while varying in the time domain, is invariant in the frequency domain. Expanding the temporal variation at each spatial node into a Fourier series transforms the unsteady governing equations into a steady set of equations in integer harmonics that can be tackled with the acceleration techniques afforded to steady-state flow solvers. Other similar approaches, such as the Nonlinear Frequency Domain [3,4,5], Reduced Frequency [6] and Time-Spectral [7, 8, 9] methods, were developed shortly thereafter. Additionally, adjoint-based optimization techniques can be applied [10, 11] as well as frequency-adaptive methods [12, 13, 14] to provide even more flexibility to the method. The Fourier temporal basis functions imply spectral convergence as the number of harmonic modes, and correspondingly number of time samples, N, is increased. Some elect to solve the equations in the frequency domain directly, while others choose to transform the equations back into the time domain to simplify the process of adding this capability to existing solvers, but each harnesses the underlying steady solution in the frequency domain. These temporal projection methods will herein be collectively referred to as Time-Spectral methods. Time-Spectral methods have demonstrated marked success in reducing the computational costs associated with simulating periodic forced flows, but have yet to be fully applied to overset or Cartesian solvers for arbitrary motion with dynamic hole-cutting. Overset and Cartesian grid methodologies are versatile techniques capable of handling complex geometry configurations in practical engineering applications, and the combination of the Time-Spectral approach with this general capability potentially provides an enabling new design and analysis tool. In an arbitrary moving-body scenario for these approaches, a Lagrangian body moves through a fixed Eulerian mesh and mesh points in the Eulerian mesh interior to the solid body are removed (cut or blanked), leaving a hole in the Eulerian mesh. During the dynamic motion some gridpoints in the domain are blanked and do not have a complete set of time-samples preventing a direct implementation of the Time-Spectral method. Murman[6] demonstrated the Time-Spectral approach for a Cartesian solver with a rigid domain motion, wherein the hole cutting remains constant. Similarly, Custer et al. [15, 16] used the NASA overset OVERFLOW solver and limited the amount of relative motion to ensure static hole-cutting and interpolation. Recently, Mavriplis and Mundis[17] demonstrated a qualitative method for applying the Time-Spectral approach to an unstructured overset solver for arbitrary motion. The goal of the current work is to develop a robust and general method for handling arbitrary motion with the Time-Spectral approach within an overset or Cartesian mesh method, while still approaching the spectral convergence rate of the original Time-Spectral approach. The viscous OVERFLOW solver will be augmented with the new Time-Spectral algorithm and the capability of the method for benchmark problems in rotorcraft and turbomachinery will be demonstrated. This abstract begins with a brief synopsis of the Time-Spectral approach for overset grids and provides details of e current approach to allow for arbitrary motion. Model problem results in one and two dimensions are included to demonstrate the viability of the method and the convergence properties. Section IV briefly outlines the implementation into the OVERFLOW solver, and the abstract closes with a description of the benchmark test cases which will be included in the final paper.

Restoration guidelines for riparian areas using dormant stock "pole" cuttings

Treesearch

Tony Barron

1996-01-01

The Open Space Division manages seven thousand acres of riparian areas comprising the Rio Grande Valley State Park. In 1988. Open Space began experimenting with dormant stock cuttings. This paper contains methods and procedures for establishing dormant stock cuttings. Dormant stock cuttings will be referred to as "poles" in this paper.

Foreign Object Damage to Tires Operating in a Wartime Environment

DTIC Science & Technology

1991-11-01

barriers were successfully overcome and the method of testing employed can now be confidently used for future test needs of this type. Data Analysis ...combined variable effects. Analysis consideration involved cut types, cut depths, number of cuts, cut/hit probabilities, tire failures, and aircraft...November 1988 with data reduction and analysis continuing into October 1989. All of the cutting tests reported in this report were conducted at the

Study of optimal laser parameters for cutting QFN packages by Taguchi's matrix method

NASA Astrophysics Data System (ADS)

Li, Chen-Hao; Tsai, Ming-Jong; Yang, Ciann-Dong

2007-06-01

This paper reports the study of optimal laser parameters for cutting QFN (Quad Flat No-lead) packages by using a diode pumped solid-state laser system (DPSSL). The QFN cutting path includes two different materials, which are the encapsulated epoxy and a copper lead frame substrate. The Taguchi's experimental method with orthogonal array of L 9(3 4) is employed to obtain optimal combinatorial parameters. A quantified mechanism was proposed for examining the laser cutting quality of a QFN package. The influences of the various factors such as laser current, laser frequency, and cutting speed on the laser cutting quality is also examined. From the experimental results, the factors on the cutting quality in the order of decreasing significance are found to be (a) laser frequency, (b) cutting speed, and (c) laser driving current. The optimal parameters were obtained at the laser frequency of 2 kHz, the cutting speed of 2 mm/s, and the driving current of 29 A. Besides identifying this sequence of dominance, matrix experiment also determines the best level for each control factor. The verification experiment confirms that the application of laser cutting technology to QFN is very successfully by using the optimal laser parameters predicted from matrix experiments.

Trace analysis of impurities in bulk gases by gas chromatography-pulsed discharge helium ionization detection with "heart-cutting" technique.

PubMed

Weijun, Yao

2007-10-12

A method has been developed for the detection of low-nL/L-level impurities in bulk gases such as H(2), O(2), Ar, N(2), He, methane, ethylene and propylene, respectively. The solution presented here is based upon gas chromatography-pulsed discharge helium ionization detection (GC-PDHID) coupled with three two-position valves, one two-way solenoid valve and four packed columns. During the operation, the moisture and heavy compounds are first back-flushed via a pre-column. Then the trace impurities (except CO(2) which is diverted to a separate analytical column for separation and detection) together with the matrix enter onto a main column, followed by the heart-cut of the impurities onto a longer analytical column for complete separation. Finally the detection is performed by PDHID. This method has been applied to different bulk gases and the applicability of detecting impurities in H(2), Ar, and N(2) are herewith demonstrated. As an example, the resulting detection limit of 100 nL/L and a dynamic range of 100-1000 nL/L have been obtained using an Ar sample containing methane.

Figure correction of a metallic ellipsoidal neutron focusing mirror

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Jiang, E-mail: jiang.guo@riken.jp; Yamagata, Yutaka; Morita, Shin-ya

2015-06-15

An increasing number of neutron focusing mirrors is being adopted in neutron scattering experiments in order to provide high fluxes at sample positions, reduce measurement time, and/or increase statistical reliability. To realize a small focusing spot and high beam intensity, mirrors with both high form accuracy and low surface roughness are required. To achieve this, we propose a new figure correction technique to fabricate a two-dimensional neutron focusing mirror made with electroless nickel-phosphorus (NiP) by effectively combining ultraprecision shaper cutting and fine polishing. An arc envelope shaper cutting method is introduced to generate high form accuracy, while a fine polishingmore » method, in which the material is removed effectively without losing profile accuracy, is developed to reduce the surface roughness of the mirror. High form accuracy in the minor-axis and the major-axis is obtained through tool profile error compensation and corrective polishing, respectively, and low surface roughness is acquired under a low polishing load. As a result, an ellipsoidal neutron focusing mirror is successfully fabricated with high form accuracy of 0.5 μm peak-to-valley and low surface roughness of 0.2 nm root-mean-square.« less

Integrated Force Method Solution to Indeterminate Structural Mechanics Problems

NASA Technical Reports Server (NTRS)

Patnaik, Surya N.; Hopkins, Dale A.; Halford, Gary R.

2004-01-01

Strength of materials problems have been classified into determinate and indeterminate problems. Determinate analysis primarily based on the equilibrium concept is well understood. Solutions of indeterminate problems required additional compatibility conditions, and its comprehension was not exclusive. A solution to indeterminate problem is generated by manipulating the equilibrium concept, either by rewriting in the displacement variables or through the cutting and closing gap technique of the redundant force method. Compatibility improvisation has made analysis cumbersome. The authors have researched and understood the compatibility theory. Solutions can be generated with equal emphasis on the equilibrium and compatibility concepts. This technique is called the Integrated Force Method (IFM). Forces are the primary unknowns of IFM. Displacements are back-calculated from forces. IFM equations are manipulated to obtain the Dual Integrated Force Method (IFMD). Displacement is the primary variable of IFMD and force is back-calculated. The subject is introduced through response variables: force, deformation, displacement; and underlying concepts: equilibrium equation, force deformation relation, deformation displacement relation, and compatibility condition. Mechanical load, temperature variation, and support settling are equally emphasized. The basic theory is discussed. A set of examples illustrate the new concepts. IFM and IFMD based finite element methods are introduced for simple problems.

The effect of cutting conditions on power inputs when machining

NASA Astrophysics Data System (ADS)

Petrushin, S. I.; Gruby, S. V.; Nosirsoda, Sh C.

2016-08-01

Any technological process involving modification of material properties or product form necessitates consumption of a certain power amount. When developing new technologies one should take into account the benefits of their implementation vs. arising power inputs. It is revealed that procedures of edge cutting machining are the most energy-efficient amongst the present day forming procedures such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc, such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc. An expanded formula for calculation of power inputs is deduced, which takes into consideration the mode of cutting together with the tip radius, the form of the replaceable multifaceted insert and its wear. Having taken as an example cutting of graphite iron by the assembled cutting tools with replaceable multifaceted inserts the authors point at better power efficiency of high feeding cutting in comparison with high-speed cutting.

Two-micron (thulium) laser resection of the prostate-tangerine technique: a new method for BPH treatment.

PubMed

Xia, Shu-Jie

2009-05-01

Two-micron (thulium) laser resection of the prostate-tangerine technique (TmLRP-TT) is a transurethral procedure that uses a thulium laser fiber to dissect whole prostatic lobes off the surgical capsule, similar to peeling a tangerine. We recently reported the primary results. Here we introduce this procedure in detail. A 70-W, 2-microm (thulium) laser was used in continuous-wave mode. We joined the incision by making a transverse cut from the level of the verumontanum to the bladder neck, making the resection sufficiently deep to reach the surgical capsule, and resected the prostate into small pieces, just like peeling a tangerine. As we resected the prostate, the pieces were vaporized, sufficiently small to be evacuated through the resectoscope sheath, and the use of the mechanical tissue morcellator was not required. The excellent hemostasis of the thulium laser ensured the safety of TmLRP-TT. No patient required blood transfusion. Saline irrigation was used intraoperatively, and no case of transurethral resection syndrome was observed. The bladder outlet obstruction had clearly resolved after catheter removal in all cases. We designed the tangerine technique and proved it to be the most suitable procedure for the use of thulium laser in the treatment of benign prostatic hyperplasia (BPH). This procedure, which takes less operative time than standard techniques, is safe and combines efficient cutting and rapid organic vaporization, thereby showing the great superiority of the thulium fiber laser in the treatment of BPH. It has been proven to be as safe and efficient as transurethral resection of the prostate (TURP) during the 1-year follow-up.

Automated segmentation of synchrotron radiation micro-computed tomography biomedical images using Graph Cuts and neural networks

NASA Astrophysics Data System (ADS)

Alvarenga de Moura Meneses, Anderson; Giusti, Alessandro; de Almeida, André Pereira; Parreira Nogueira, Liebert; Braz, Delson; Cely Barroso, Regina; deAlmeida, Carlos Eduardo

2011-12-01

Synchrotron Radiation (SR) X-ray micro-Computed Tomography (μCT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-μCT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-μCT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-μCT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.

Liver vessels segmentation using a hybrid geometrical moments/graph cuts method

PubMed Central

Esneault, Simon; Lafon, Cyril; Dillenseger, Jean-Louis

2010-01-01

This paper describes a fast and fully-automatic method for liver vessel segmentation on CT scan pre-operative images. The basis of this method is the introduction of a 3-D geometrical moment-based detector of cylindrical shapes within the min-cut/max-flow energy minimization framework. This method represents an original way to introduce a data term as a constraint into the widely used Boykov’s graph cuts algorithm and hence, to automate the segmentation. The method is evaluated and compared with others on a synthetic dataset. Finally, the relevancy of our method regarding the planning of a -necessarily accurate- percutaneous high intensity focused ultrasound surgical operation is demonstrated with some examples. PMID:19783500

RECOVERY ACT: MULTIMODAL IMAGING FOR SOLAR CELL MICROCRACK DETECTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janice Hudgings; Lawrence Domash

2012-02-08

Undetected microcracks in solar cells are a principal cause of failure in service due to subsequent weather exposure, mechanical flexing or diurnal temperature cycles. Existing methods have not been able to detect cracks early enough in the production cycle to prevent inadvertent shipment to customers. This program, sponsored under the DOE Photovoltaic Supply Chain and Cross-Cutting Technologies program, studied the feasibility of quantifying surface micro-discontinuities by use of a novel technique, thermoreflectance imaging, to detect surface temperature gradients with very high spatial resolution, in combination with a suite of conventional imaging methods such as electroluminescence. The project carried out laboratorymore » tests together with computational image analyses using sample solar cells with known defects supplied by industry sources or DOE National Labs. Quantitative comparisons between the effectiveness of the new technique and conventional methods were determined in terms of the smallest detectable crack. Also the robustness of the new technique for reliable microcrack detection was determined at various stages of processing such as before and after antireflectance treatments. An overall assessment is that the new technique compares favorably with existing methods such as lock-in thermography or ultrasonics. The project was 100% completed in Sept, 2010. A detailed report of key findings from this program was published as: Q.Zhou, X.Hu, K.Al-Hemyari, K.McCarthy, L.Domash and J.Hudgings, High spatial resolution characterization of silicon solar cells using thermoreflectance imaging, J. Appl. Phys, 110, 053108 (2011).« less